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DOI： 10.1161/CIRCIMAGING.122.014895

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PURPOSE: To evaluate left atrial (LA) function in patients with hypertrophic cardiomyopathy (HCM) by LA strain assessment using cardiac computed tomography (CT-derived LA strain). MATERIALS AND METHODS: This was a retrospective study of 34 patients with HCM and 31 non-HCM patients who underwent cardiac computed tomography (CT) using retrospective electrocardiogram-gated mode. CT images were reconstructed every 5% (0-95%) of the RR intervals. CT-derived LA strain (reservoir [LASr], conduit [LASc], and booster pump strain [LASp]) were semi-automatically analyzed using a dedicated workstation. We also measured the left atrial volume index (LAVI) and left ventricular longitudinal strain (LVLS) for the left atrial and ventricular functional parameters to assess the relationship with CT-derived LA strain. RESULTS: CT-derived LA strain significantly correlated with LAVI: r = - 0.69, p < 0.001 for LASr; r = - 0.70, p < 0.001 for LASp; and r = - 0.35, p = 0.004 for LASc. CT-derived LA strain also significantly correlated with LVLS: r = - 0.62, p < 0.001 for LASr; r = - 0.67, p < 0.001 for LASc; and r = - 0.42, p = 0.013 for LASp. CT-derived LA strain in patients with HCM was significantly lower than that in non-HCM patients: LASr (20.8 ± 7.6 vs. 31.7 ± 6.1%, p < 0.001); LASc (7.9 ± 3.4 vs. 14.2 ± 5.3%, p < 0.001); and LASp (12.8 ± 5.7 vs. 17.6 ± 4.3%, p < 0.001). Additionally, CT-derived LA strain showed high reproducibility; inter-observer correlation coefficients were 0.94, 0.90, and 0.89 for LASr, LASc, and LASp, respectively. CONCLUSION: CT-derived LA strain is feasible for quantitative assessment of left atrial function in patients with HCM.

DOI： 10.1007/s11604-023-01401-6

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OBJECTIVE: This study aimed to compare the image quality in the hepatobiliary phase images of gadoxetic acid-enhanced liver magnetic resonance imaging using parallel imaging (PI) and compressed sensing (CS) reconstruction, using variable CS factors with the standard method using the PI technique. METHODS: In this study, 64 patients who underwent gadoxetic acid-enhanced liver magnetic resonance imaging at 3.0 T were enrolled. Hepatobiliary phase images were acquired 6 times using liver acquisition with volume acceleration (LAVA) and CS reconstruction with 5 CS factors 1.4, 1.6, 1.8, 2.0, and 2.5 (LAVA-CS 1.4, 1.6, 1.8, 2.0, and 2.5) and standard LAVA (LAVA-noCS). For objective analysis, the signal intensity ratios (SIRs) of the liver-to-spleen (SIRliver/spleen), liver-to-portal vein (SIRliver/portal vein), and liver-to-fat (SIRliver/fat) were estimated. For subjective analysis, 2 radiologists independently evaluated the quality of all the images. RESULTS: The objective analysis demonstrated no significant difference in all evaluation parameters of all the images. Subjective analysis revealed that the scores of all evaluation items were higher for LAVA-noCS images than for LAVA-CS images, and only LAVA-CS 1.4 did not significantly differ from LAVA-noCS in all evaluation items (P = 1.00 in 2 readers). CONCLUSIONS: A CS factor of 1.4 in the hepatobiliary phase image with combined PI and CS can reduce the scan time without degrading the image quality compared with the standard method.

DOI： 10.1097/RCT.0000000000001451

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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The present study aimed to evaluate the optimal timing of radium-223 chloride (Ra-223) administration among patients with bone metastasis from castration-resistant prostate cancer (BmCRPC). Patients, who were diagnosed with BmCRPC and treated with Ra-223 therapy between October, 2016 and January, 2022, were reviewed. The survival time was calculated from the initiation of Ra-223 administration. The time from the diagnosis of BmCRPC to the initiation of Ra-223 administration was identified as a potential prognostic factor. A total of 51 patients were examined in the present study. Ra-223 was administered as the first- and second-line therapy (earlier Ra-223 administration) in 32 patients and as the third- to fifth-line therapy (later Ra-223 administration) in 19 patients. In the multivariate analysis, which considered the potential prognosis, the difference in survival times between patients who received early and late Ra-223 administration was not significant [hazard ratio (HR), 2.67; 95% confidence interval (CI), 0.79-9.07; P=0.11]. By contrast, an incomplete Ra-223 administration (HR, 128.03; 95% CI, 10.59-1548.42; P<0.01) and higher levels of prostate-specific antigen prior to Ra-223 administration (HR, 7.86; 95% CI, 2.7-27.24; P<0.01) were independent factors, significantly associated with a poorer prognosis. The timing of Ra-223 administration did not significantly affect the survival of patients from the initiation of treatment. Further studies are thus required to determine the optimal timing for Ra-223 administration.

DOI： 10.3892/mi.2023.98

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RATIONALE AND OBJECTIVES: We aimed to evaluate the impact of four-dimensional noise reduction filtering using a four-dimensional similarity filter (4D-SF) on radiation dose reduction in dynamic myocardial computed tomography perfusion (CTP). MATERIALS AND METHODS: Forty-three patients who underwent dynamic myocardial CTP using 320-row computed tomography (CT) were included in the study. The original images were reconstructed using iterative reconstruction (IR). Three different CTP datasets with simulated noise, corresponding to 25%, 50%, and 75% reduction of the original dose (300 mA), were reconstructed using a combination of IR and 4D-SF. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed, and CT-derived myocardial blood flow (CT-MBF) was quantified. The results were compared between the original and simulated images with radiation dose reduction. RESULTS: The median SNR (first quartile-third quartile) at the original, 25%-, 50%-, and 75%-dose reduced-simulated images with 4D-SF was 8.3 (6.5-10.2), 16.5 (11.9-21.7), 15.6 (11.0-20.1), and 12.8 (8.8-18.1) and that of CNR was 4.4 (3.2-5.8), 6.7 (4.6-10.3), 6.6 (4.3-10.1), and 5.5 (3.5-9.1), respectively. All the dose-reduced-simulated CTPs with 4D-SF had significantly higher image quality scores in SNR and CNR than the original ones (25%-, 50%-, and 75%-dose reduced vs. original images, p < 0.05, in each). The CT-MBF in 75%-dose reduced-simulated CTP was significantly lower than 25%-, 50%- dose-reduced-simulated, and original CTPs (vs. 75%-dose reduced-simulated images, p < 0.05, in each). CONCLUSION: 4D-SF has the potential to reduce the radiation dose associated with dynamic myocardial CTP imaging by half, without impairing the robustness of MBF quantification.

DOI： 10.3389/fradi.2023.1214521

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AIM: To evaluate the usefulness of synthetic magnetic resonance imaging (MRI) performed before the initiation of neoadjuvant chemotherapy (NAC) in predicting whether breast cancers can achieve a pathological complete response (pCR) after the completion of NAC. MATERIALS AND METHODS: This retrospective study investigated 37 consecutive patients with 39 breast cancers (pCR: 14, and non-pCR: 25) who underwent dynamic contrast-enhanced (DCE)-MRI and synthetic MRI before the initiation of NAC. Using synthetic MRI images, quantitative values (T1 and T2 relaxation times, proton density [PD] and their standard deviations [SD]) were obtained in breast lesions, before (Pre-T1, Pre-T2, Pre-PD, SD of Pre-T1, SD of Pre-T2, SD of Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD, SD of Gd-T1, SD of Gd-T2, SD of Gd-PD) contrast agent injection. The aforementioned quantitative values and several morphological features that were identified on DCE-MRI were compared between pCR and non-pCR. RESULTS: Multivariate analyses revealed that the SD of Pre-T2 (p=0.038) was significant and was an independent predictor of pCR, with an area under the receiver operating characteristics curve of 0.829. The sensitivity, specificity, and accuracy of the SD of Pre-T2 with an optimal cut-off value of 11.5 were 71.4%, 80%, and 76.3%, respectively. CONCLUSIONS: The SD of Pre-T2 obtained from synthetic MRI was used successfully to predict those breast cancers that would achieve a pCR after the completion of NAC; however, these results are preliminary and need to be verified by further studies.

DOI： 10.1016/j.crad.2022.06.019

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PURPOSE: We applied a combination of compressed-sensing (CS) and retrospective motion correction to free-breathing cine magnetic resonance (MR) (FBCS cine MoCo). We validated FBCS cine MoCo by comparing it with breath-hold (BH) conventional cine MR. MATERIALS AND METHODS: Thirty-five volunteers underwent both FBCS cine MoCo and BH conventional cine MR imaging. Twelve consecutive short-axis cine images were obtained. We compared the examination time, image quality and biventricular volumetric assessments between the two cine MR. RESULTS: FBCS cine MoCo required a significantly shorter examination time than BH conventional cine (135 s [110-143 s] vs. 198 s [186-349 s], p < 0.001). The image quality scores were not significantly different between the two techniques (End-diastole: FBCS cine MoCo; 4.7 ± 0.5 vs. BH conventional cine; 4.6 ± 0.6; p = 0.77, End-systole: FBCS cine MoCo; 4.5 ± 0.5 vs. BH conventional cine; 4.5 ± 0.6; p = 0.52). No significant differences were observed in all biventricular volumetric assessments between the two techniques. The mean differences with 95% confidence interval (CI), based on Bland-Altman analysis, were - 0.3 mL (- 8.2 - 7.5 mL) for LVEDV, 0.2 mL (- 5.6 - 5.9 mL) for LVESV, - 0.5 mL (- 6.3 - 5.2 mL) for LVSV, - 0.3% (- 3.5 - 3.0%) for LVEF, - 0.1 g (- 8.5 - 8.3 g) for LVED mass, 1.4 mL (- 15.5 - 18.3 mL) for RVEDV, 2.1 mL (- 11.2 - 15.3 mL) for RVESV, - 0.6 mL (- 9.7 - 8.4 mL) for RVSV, - 1.0% (- 6.5 - 4.6%) for RVEF. CONCLUSION: FBCS cine MoCo can potentially replace multiple BH conventional cine MR and improve the clinical utility of cine MR.

DOI： 10.1007/s11604-022-01344-4

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Language：English  

Pulmonary artery intimal sarcomas (PAIS) are often misdiagnosed as pulmonary embolisms (PE) as their clinical findings and imaging findings are similar. However, given the clinical outcome of both diseases is different in its prognosis, accurate and rapid diagnosis is mandatory. This is a case report of a histologically-proven PAIS which was initially treated as a PE. The color-coded iodine map using dual-energy computed tomography (dual-energy CT iodine map) well reflected the distribution of the tumor consistent with 18fluoro-2-deoxyglucose-uptake region using positron emission tomography/CT. This case demonstrates the potential of using dual-energy CT iodine map to differentiate PAIS from PE. Learning objective: Use of a dual-energy computed tomography iodine map to visualize a pulmonary artery intimal sarcoma may provide useful diagnostic information.

DOI： 10.1016/j.jccase.2022.03.011

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BACKGROUND: Diagnostic guidelines for isolated cardiac sarcoidosis (iCS) were first proposed in 2016, but there are few reports on the imaging and prognosis of iCS. This study aimed to evaluate the use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging in predicting iCS prognosis. METHODS AND RESULTS: We retrospectively reviewed the clinical and imaging data of 306 consecutive patients with suspected CS who underwent FDG PET/CT with a dedicated preparation protocol and included 82 patients (55 with systemic sarcoidosis including cardiac involvement [sCS], 27 with iCS) in the study. We compared the FDG PET/CT findings between the two groups. We examined the relationship between the CS type and the rate of adverse cardiac events. The iCS group had a significantly lower target-to-background ratio than the sCS group (P = 0.0010). The event-free survival rate was significantly lower in the iCS group than the sCS group (log-rank test, P < 0.0001). iCS was identified as an independent prognostic factor for adverse events (hazard ratio 3.82, P = 0.0059). CONCLUSION: iCS was an independent prognostic factor for adverse cardiac events in patients with CS. The clinical diagnosis of iCS based on FDG PET/CT and new guidelines may be important.

DOI： 10.1007/s12350-022-03034-0

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A non-traumatic abdominal wall hematoma is rare, and occurs occasionally due to coughing, physical activity, or antithrombotic/anticoagulant therapy. The condition is usually unilateral; however, rare bilateral cases have been reported. Here, we report a rare case of a non-traumatic bilateral rectus sheath hematoma. The patient was a 60-year-old woman who was urgently admitted to our hospital due to the occurrence of pneumonia during postoperative chemotherapy for breast cancer. Because she exhibited disseminated intravascular coagulation, a therapy with antibacterial agents, thrombomodulin alpha, and catecholamines was initiated. During hospitalization, hemorrhagic shock due to hematomas in both rectus abdominis muscles was observed without any discernible cause. Subsequent emergency angioembolization was successful, and abdominal computed tomography performed 3 months after the onset of the rectus sheath hematoma confirmed a reduction in the hematoma size.

DOI： 10.1016/j.radcr.2022.02.074

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Language：Japanese   Publisher：産業開発機構(株)  

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We evaluated the feasibility of myocardial perfusion ratio to the aorta (MPR) in static computed tomography perfusion (CTP) for detecting myocardial perfusion abnormalities assessed by single-photon emission computed tomography (SPECT). Twenty-five patients with suspected coronary artery disease who underwent dynamic CTP and SPECT were retrospectively evaluated. CTP images scanned at a sub-optimal phase for detecting myocardial perfusion abnormalities were selected from dynamic CTP images and used as static CTP images in the present study. The diagnostic accuracy of MPR derived from static CTP was compared to those of visual assessment and conventional quantitative parameters such as myocardial CT attenuation (HU) and transmural perfusion ratio (TPR). The area under the curve of MPR (0.84; 95% confidence interval [CI], 0.76-0.90) was significantly higher than those of myocardial CT attenuation (0.73; 95% CI, 0.65-0.79) and TPR (0.76; 95% CI, 0.67-0.83) (p &lt; 0.05). Sensitivity and specificity were 67% (95% CI, 54-77%) and 90% (95% CI, 86-92%) for visual assessment, 51% (95% CI, 39-63%) and 86% (95% CI, 82-89%) for myocardial CT attenuation, 63% (95% CI, 51-74%) and 84% (95% CI, 80-88%) for TPR, and 78% (95% CI, 66-86%) and 84% (95% CI, 80-88%) for MPR, respectively. MPR showed higher diagnostic accuracy for detecting myocardial perfusion abnormality compared with myocardial CT attenuation and TPR.

DOI： 10.3390/jcm11071816

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BACKGROUND: This study aimed to quantitatively evaluate myocardial perfusion single-photon emission computed tomography (SPECT) using an original analysis tool in the compartment model for detecting regional significant coronary artery disease (CAD).Methods and Results:This study analyzed 41 patients (median age, 76 years) with suspected or known CAD who underwent both dynamic SPECT using 99 mTc-tetrofosmin and invasive coronary angiography. The quantitative analysis was performed using a single-tissue compartment model to evaluate the diagnostic performance of the myocardial flow reserve (MFR) for regional significant CAD, excluding infarcted territories. In the regional analysis, 114 vessels were assessed, of which 31 were diagnosed as significant coronary lesions (≥70% stenosis and/or fraction flow reserve ≤0.8). The MFR of regional significant CAD was significantly lower than that of non-significant CAD (1.11 [0.97-1.31] vs. 1.74 [1.30-2.27]; P<0.001). In the receiver operating characteristic curve analysis, the MFR displayed an area under the curve (AUC) of 0.81. While analyzing each coronary artery territory, the diagnostic performance of the MFR value in the left anterior descending (LAD) artery territory was found to be significantly higher than that found in qualitative assessment (AUC: 0.84 vs. 0.61). CONCLUSIONS: A quantitative analysis of dynamic SPECT data facilitated detecting regional CAD. For the LAD artery, the MFR displayed a higher diagnostic performance than the qualitative assessment of conventional myocardial perfusion SPECT.

DOI： 10.1253/circj.CJ-21-0966

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BACKGROUND: Total hepatic vascular exclusion (THVE) is an essential technique to control hemorrhage during surgical treatment of advanced liver tumors or injury. However, surgeons often have difficulty securing the intrapericardial inferior vena cava (IVC) because few reports have described the anatomy around the supra-diaphragmatic IVC or the techniques and surgical outcomes for this procedure. This study presents our safe and feasible intrapericardial IVC approach, which is based on anatomical landmarks, and reports the surgical outcomes of this procedure. METHODS: We performed THVE using our technique for hepatectomy, accompanied by resection of the hepatic vein confluence or tumor thrombectomy of the supra-hepatic IVC, in five patients between August 2011 and March 2018. RESULTS: The mean operative time was 568 min (range: 240-820 min). The mean THVE time was 10 min (range: 5-15 min), with a mean blood loss of 1882 mL (range: 1010-3100 mL). Postoperatively, one patient was classified as Clavien-Dindo grade II due to medication for tachycardia, and two patients were classified as grade IIIa due to drainage of bile and pleural effusion, including one patient with tachycardia. The mean postoperative hospital stay was 26 days (range: 18-34 days). No patient exhibited decreased cardiac function during surgery or postoperatively, and no patient experienced thoracotomy or phrenic nerve paralysis. CONCLUSIONS: Anatomical landmarks are important to ensure a safe approach to the intrapericardial IVC. Incising the pericardium does not lead to serious problems. The transmediastinal, intrapericardial IVC approach for THVE is a feasible method to secure the supra-diaphragmatic intrapericardial IVC.

DOI： 10.1007/s00423-021-02246-1

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BACKGROUND: Over the past decades, remarkable advancements in systemic drug therapy have improved the prognosis of patients with bone metastases. Individualization is required in external beam radiotherapy (EBRT) for bone metastases according to the patient's prognosis. To establish individualized EBRT for bone metastases, we investigated factors that affect the local control (LC) of bone metastases. METHODS: Between January 2010 and December 2019, 536 patients received EBRT for 751 predominantly osteolytic bone metastases. LC at EBRT sites was evaluated with a follow-up computed tomography. The median EBRT dose was biologically effective dose (BED10) (39.0) (range of BED10: 14.4-71.7 Gy). RESULTS: The median follow-up time and median time of computed tomography follow-up were 11 (range 1-123) months and 6 (range 1-119) months, respectively. The 0.5- and 1-year overall survival rates were 73% and 54%, respectively. The 0.5- and 1-year LC rates were 83% and 79%, respectively. In multivariate analysis, higher age (≥ 70 years), non-vertebral bone metastases, unfavorable primary tumor sites (esophageal cancer, colorectal cancer, hepatobiliary/pancreatic cancer, renal/ureter cancer, sarcoma, melanoma, and mesothelioma), lower EBRT dose (BED10 < 39.0 Gy), and non-administration of bone-modifying agents (BMAs)/antineoplastic agents after EBRT were significantly unfavorable factors for LC of bone metastases. There was no statistically significant difference in the LC between BED10 = 39.0 and BED10 > 39.0 Gy. CONCLUSIONS: Regarding tumor-related factors, primary tumor sites and the sites of bone metastases were significant for the LC. As for treatment-related factors, lower EBRT doses (BED10 < 39.0 Gy) and non-administration of BMAs/antineoplastic agents after EBRT were associated with poor LC. Dose escalation from BED10 = 39.0 Gy did not necessarily improve LC.

DOI： 10.1186/s13014-021-01940-0

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Background: Single-center studies indicated a high diagnostic accuracy of dynamic computed tomography perfusion (CTP) imaging in the diagnosis of coronary artery disease (CAD). Objectives: This prospective multicenter study determined the diagnostic performance of combined coronary computed tomography angiography (CTA) and CTP for detecting hemodynamically significant CAD defined by invasive coronary angiography (ICA) with fractional flow reserve (FFR). Methods: Seven centers enrolled 174 patients with suspected or known CAD who were clinically referred for ICA. CTA and dynamic CTP were performed using dual-source CT before ICA. FFR was done as part of ICA in the case of 26% to 90% coronary diameter stenosis. Hemodynamically significant stenosis was defined as FFR of <0.8 or >90% stenosis on ICA. Results: The study protocol was completed in 157 participants, and hemodynamically significant stenosis was detected in 76 of 157 patients (48%) and 112 of 442 vessels (25%). According to receiver-operating characteristic curve analysis, adding dynamic CTP to CTA significantly increased the area under the curve from 0.65 (95% CI: 0.57-0.72) to 0.74 (95% CI: 0.66-0.81; P = 0.011) on the patient level, with decreased sensitivity (93% vs 72%; P < 0.001), improved specificity (36% vs 75%; P < 0.001), and improved overall accuracy (64% vs 74%; P < 0.001). Conclusions: In this prospective multicenter study on dynamic CTP, the combination of anatomic assessment with coronary CTA and functional evaluation with dynamic CTP allowed more accurate identification of hemodynamically significant CAD compared with CTA alone. However, the clinical significance of this approach needs to be further investigated, including its usefulness in improving prognosis. (Assessment of Myocardial Perfusion Linked to Infarction and Fibrosis Explored With Dual-Source CT [AMPLIFiED]; UMIN000016353)

DOI： 10.1016/j.jacc.2021.08.067

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

PURPOSE: This study aimed to compare the characteristics of triple-negative breast cancer (TNBC) with non-TNBC on dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and synthetic MRI. METHOD: This retrospective study included 79 patients with histopathologically proven breast cancer (TNBC: 16, non-TNBC: 63) who underwent synthetic MRI. Using synthetic MR images, we obtained T1 and T2 relaxation times in breast lesions before (Pre-T1, Pre-T2, Pre-PD) and after (Gd-T1, Gd-T2, Gd-PD) contrast agent injection. Subsequently, we calculated the ΔT1 (Pre-T1 - Gd-T1), ΔT2 (Pre-T2 - Gd-T2), Pre-T1/T2, and Gd-T1/T2. We compared the aforementioned quantitative values, as well as several morphologic features between TNBCs and non-TNBCs that were identified on DCE-MRI. RESULTS: The multivariate analyses revealed that the Pre-T2 (P = 0.037) and the presence of rim enhancement (P-RIM) (P = 0.034) were significant and independent predictors of TNBC. The area under the receiver operating characteristics curve for all breast cancers was greater when a combination of Pre-T2 and P-RIM (Pre-T2＋P-RIM; Method 3, AUC (area under the curve) = 0.858) was used to distinguish between TNBCs and non-TNBCs versus the use of either Pre-T2 alone (Method 1, AUC = 0.786) or P-RIM alone (Method 2, AUC = 0.747). CONCLUSIONS: Pre-T2 obtained using synthetic MRI and P-RIM identified on DCE-MRI allowed the differentiation between TNBCs and non-TNBCs. However, these results are preliminary and need to be verified by further studies.

DOI： 10.1016/j.ejrad.2021.109838

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BACKGROUND: Deep learning-based methods have been used to denoise magnetic resonance imaging. PURPOSE: The purpose of this study was to evaluate a deep learning reconstruction (DL Recon) in cardiovascular black-blood T2-weighted images and compare with intensity filtered images. MATERIAL AND METHODS: Forty-five DL Recon images were compared with intensity filtered and the original images. For quantitative image analysis, the signal to noise ratio (SNR) of the septum, contrast ratio (CR) of the septum to lumen, and sharpness of the endocardial border were calculated in each image. For qualitative image quality assessment, a 4-point subjective scale was assigned to each image (1 = poor, 2 = fair, 3 = good, 4 = excellent). RESULTS: The SNR and CR were significantly higher in the DL Recon images than in the intensity filtered and the original images (p < .05 in each). Sharpness of the endocardial border was significantly higher in the DL Recon and intensity filtered images than in the original images (p < .05 in each). The image quality of the DL Recon images was significantly better than that of intensity filtered and original images (p < .001 in each). CONCLUSIONS: DL Recon reduced image noise while improving image contrast and sharpness in the cardiovascular black-blood T2-weight sequence.

DOI： 10.1177/20584601211044779

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OBJECTIVE: Albumin-globulin ratio (AGR), which is calculated by dividing serum albumin by serum globulin, is considered as a cancer-related inflammation biomarker. Although the prognosis of many solid cancers has been shown to be associated with AGR, there are no studies to demonstrate the association between the prognosis of thyroid cancer and AGR. The purpose of this study is to reveal the relationship between AGR and overall survival (OS) in patients with thyroid cancer who received radioactive iodine therapy (RIT). METHODS: Eighty-eight patients with thyroid cancer who had received RIT for the first time in our institution were included. The values before RIT were adopted as initial measurements for serum albumin, globulin, and thyroglobulin (Tg) and used for analysis. Patients were divided into two groups based on the AGR value. We analyzed the relationship between clinical factors and treatment outcome. RESULTS: The median follow-up period was 92.4 months (range: 30.1-173.9 months). The 5-year OS and progression-free survival (PFS) were 94% and 54%, respectively. Seventeen patients (< 65 years, 8; and ≥ 65 years, 9) died during the follow-up period. Low AGR was significantly associated with OS in both univariate and multivariate analyses (p = 0.0059 and p = 0.0120, respectively). As the 5-year OS was as high as 94%, there was no significant difference in survival rate between the two groups during the first 5 years. However, there seemed to be a remarkable difference in 10 years after the first RIT. On the other hand, Tg was significantly associated with PFS in both univariate and multivariate analyses (p = 0.0016 and p = 0.0441, respectively). In patients under the age of 65, the PFS rate was significantly lower in the low AGR group (p < 0.0001), while there was no difference in PFS rate between the two AGR groups in patients aged 65 years or older. CONCLUSIONS: AGR may be used as a prognostic factor in relatively younger patients with thyroid cancer treated with radioiodine, while it may be less useful in the older. Overall, it may be an independent prognostic factor for long-term survival in those with thyroid cancer.

DOI： 10.1007/s12149-021-01635-2

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We investigated the prognostic significance and treatment outcomes of pretreatment inflammatory response markers for locally advanced squamous cell carcinoma (SCC) of the external auditory canal (EAC) and middle ear (ME). Between July 2003 and July 2019, 21 patients with SCC of the EAC (n = 18) or ME (n = 3) who received radiotherapy with or without surgery or systemic therapy (radiotherapy alone [n = 2], radiotherapy + systemic therapy [n = 6], radiotherapy + surgery [n = 7], radiotherapy + surgery + systemic therapy [n = 6]) were retrospectively examined. The median radiation dose was 66.0 (range, 50.4-70.0) Gy, with daily fractions of 1.8-2.0 Gy. The median follow-up period was 25 months (range, 6-137). The two-year overall survival (OS), progression-free survival (PFS), and locoregional control (LC) rates were 61%, 48%, and 55%, respectively. OS, PFS, and LC did not differ significantly according to patient- (age, sex), tumor- (Pittsburgh stage, pretreatment neurological findings), and treatment-related (surgery or systemic therapy, radiation dose, prophylactic neck irradiation) factors. Conversely, there were significant differences in OS, PFS, and LC between patients with high and low pretreatment C-reactive protein-to-albumin ratios (p = 0.002, 0.003, and 0.004, respectively). OS also differed significantly between patients with high and low pretreatment neutrophil-to-lymphocyte ratios (NLR; p = 0.037). Other inflammatory response markers, including platelet-to-lymphocyte ratio (PLR) and albumin-to-globulin ratio (AGR), did not influence OS, PFS, or LC. Our findings suggest that pretreatment C-reactive protein-to-albumin ratio and NLRs have a significant impact on treatment outcomes in patients with locally advanced SCC of the EAC and ME.

DOI： 10.1093/jrr/rrab048

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Computed tomography (CT)-derived three-dimensional maximum principal strain (MP-strain) can provide incremental value to coronary CT angiography for cardiac dysfunction assessment with high diagnostic performance in patients with myocardial infarction. Global longitudinal strain (GLS) measured using two-dimensional speckle tracking echocardiography (2D-STE) is more sensitive than left ventricular ejection fraction (LVEF) for detecting early myocardial dysfunction. We aimed to compare CT-derived MP-strain with each of 2D-STE-derived strains (i.e., longitudinal, circumferential, and radial strains), and identify the major determinants of CT-derived MP-strain among 2D-STE-derived strains. We studied 51 patients who underwent cardiac CT and echocardiography. CT images were reconstructed at every 5% (0-95%) of the RR interval. A dedicated workstation was used to analyze CT-derived MP-strain on the 16-segment model. We calculated CT-derived global MP-strain with all the 16 segments on a per patient basis. Pearson's test was used to assess correlations between CT-derived MP-strain and STE-strain at global and segmental levels. The intra-class correlation coefficient for interobserver agreement for CT-derived global MP-strain was 0.98 (95% confidence interval 0.96-0.99). The low-CT-derived global MP-strain group (≤ 0.43) had more patients with LV dysfunction than the high-CT-derived global MP-strain group (> 0.43). CT-derived global MP-strain was associated with STE-GLS (r = 0.738, P < 0.001), global circumferential strain (r = 0.646, P < 0.001), and global radial strain (r = 0.432, P = 0.001). In multivariate analysis, STE-GLS had the strongest association to CT-derived global MP-strain among three directional STE-strains and LVEF by echocardiography (standardized coefficient =  - 0.527, P < 0.001). STE-GLS is a major determinant of CT-derived global MP-strain. CT-derived MP-strain may enhance the value of coronary CT angiography by adding functional information to CT-derived LVEF.

DOI： 10.1007/s00380-021-01901-3

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Volumetric-modulated arc therapy (VMAT) requires highly accurate control of multileaf collimator (MLC) movement, rotation speed of linear accelerator gantry, and monitor units during irradiation. Pretreatment validation and monitoring of these factors during irradiation are necessary for appropriate VMAT treatment. Recently, a gantry mounted transmission detector "Delta4 Discover® (D4D)" was developed to detect errors in delivering doses and dose distribution immediately after treatment. In this study, the performance of D4D was evaluated. Simulation plans, in which the MLC position was displaced by 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mm from the clinically used original plans, were created for ten patients who received VMAT treatment for prostate cancer. Dose deviation (DD), distance-to-agreement (DTA), and gamma index analysis (GA) for each plan were evaluated by D4D. These results were compared to the results (DD, DTA and GA) measured by Delta4 Phantom + (D4P). We compared the deviations between the planned and measured values of the MLC stop positions A-side and B-side in five clinical cases of prostate VMAT during treatment and measured the GA values. For D4D, when the acceptable errors for DD, DTA, and GA were determined to be ≤3%, ≤2 mm, and ≤3%/2 mm, respectively, the minimum detectable errors in the MLC position were 2.0, 1.5, and 1.5 mm based on DD, DTA, and GA respectively. The corresponding minimum detectable MLC position errors were 2.0, 1.0, and 1.5 mm, respectively, for D4P. The deviation between the planned and measured position of MLC stopping point of prostate VMAT during treatment was stable at an average of -0.09 ± 0.05 mm, and all GA values were above 99.86%. In terms of delivering doses and dose distribution of VMAT, error detectability of D4D was comparable to that of D4P. The transmission-type detector "D4D" is thus suitable for detecting delivery errors during irradiation.

DOI： 10.1002/acm2.13260

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DOI： 10.1253/circj.CJ-19-1131

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BACKGROUND: Feature tracking (FT) has become an established tool for cardiovascular magnetic resonance (CMR)-based strain analysis. Recently, the compressed sensing (CS) technique has been applied to cine CMR, which has drastically reduced its acquisition time. However, the effects of CS imaging on FT strain analysis need to be carefully studied. This study aimed to investigate the use of CS cine CMR for FT strain analysis compared to conventional cine CMR. METHODS: Sixty-five patients with different left ventricular (LV) pathologies underwent both retrospective conventional cine CMR and prospective CS cine CMR using a prototype sequence with the comparable temporal and spatial resolution at 3 T. Eight short-axis cine images covering the entire LV were obtained and used for LV volume assessment and FT strain analysis. Prospective CS cine CMR data over 1.5 heartbeats were acquired to capture the complete end-diastolic data between the first and second heartbeats. LV volume assessment and FT strain analysis were performed using a dedicated software (ci42; Circle Cardiovasacular Imaging, Calgary, Canada), and the global circumferential strain (GCS) and GCS rate were calculated from both cine CMR sequences. RESULTS: There were no significant differences in the GCS (- 17.1% [- 11.7, - 19.5] vs. - 16.1% [- 11.9, - 19.3; p = 0.508) and GCS rate (- 0.8 [- 0.6, - 1.0] vs. - 0.8 [- 0.7, - 1.0]; p = 0.587) obtained using conventional and CS cine CMR. The GCS obtained using both methods showed excellent agreement (y = 0.99x - 0.24; r = 0.95; p < 0.001). The Bland-Altman analysis revealed that the mean difference in the GCS between the conventional and CS cine CMR was 0.1% with limits of agreement between -2.8% and 3.0%. No significant differences were found in all LV volume assessment between both types of cine CMR. CONCLUSION: CS cine CMR could be used for GCS assessment by CMR-FT as well as conventional cine CMR. This finding further enhances the clinical utility of high-speed CS cine CMR imaging.

DOI： 10.1186/s12968-021-00708-5

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BACKGROUND: The addition of synthetic MRI might improve the diagnostic performance of dynamic contrast-enhanced MRI (DCE-MRI) in patients with breast cancer. PURPOSE: To evaluate the diagnostic value of a combination of DCE-MRI and quantitative evaluation using synthetic MRI for differentiation between benign and malignant breast masses. STUDY TYPE: Retrospective, observational. POPULATION: In all, 121 patients with 131 breast masses who underwent DCE-MRI with additional synthetic MRI were enrolled. FIELD STRENGTH/SEQUENCE: 3.0 Tesla, T1 -weighted DCE-MRI and synthetic MRI acquired by a multiple-dynamic, multiple-echo sequence. ASSESSMENT: All lesions were differentiated as benign or malignant using the following three diagnostic methods: DCE-MRI type based on the Breast Imaging-Reporting and Data System; synthetic MRI type using quantitative evaluation values calculated by synthetic MRI; and a combination of the DCE-MRI + Synthetic MRI types. The diagnostic performance of the three methods were compared. STATISTICAL TESTS: Univariate (Mann-Whitney U-test) and multivariate (binomial logistic regression) analyses were performed, followed by receiver-operating characteristic curve (AUC) analysis. RESULTS: Univariate and multivariate analyses showed that the mean T1 relaxation time in a breast mass obtained by synthetic MRI prior to injection of contrast agent (pre-T1 ) was the only significant quantitative value acquired by synthetic MRI that could independently differentiate between malignant and benign breast masses. The AUC for all enrolled breast masses assessed by DCE-MRI + Synthetic MRI type (0.83) was significantly greater than that for the DCE-MRI type (0.70, P < 0.05) or synthetic MRI type (0.73, P < 0.05). The AUC for category 4 masses assessed by the DCE-MRI + Synthetic MRI type was significantly greater than that for those assessed by the DCE-MRI type (0.74 vs. 0.50, P < 0.05). DATA CONCLUSION: A combination of synthetic MRI and DCE-MRI improves the accuracy of diagnosis of benign and malignant breast masses, especially category 4 masses. Level of Evidence 4 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:381-391.

DOI： 10.1002/jmri.27362

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Three-dimensional high-resolution late gadolinium enhancement (3D HR LGE) magnetic resonance imaging (MRI) using compressed sensing can help detect small myocardial infarcts. We discuss the case of an 11-year-old child with an anomalous aortic origin of the left coronary artery. Since he was suspected to have coronary stenosis due to anomalous aortic origin of the left coronary artery, cardiovascular MRI, including conventional two-dimensional (2D) LGE MRI and HR 3D LGE MRI, was conducted. Myocardial scars were not clearly observed via 2D LGE MRI; however, 3D HR MRI revealed subendocardial infarction of the anteroseptal wall, which corresponded to the left coronary artery. By applying the compressed sensing technique, 3D HR LGE, MRI enables a detailed assessment of small myocardial infarcts in a clinically feasible scan time.

DOI： 10.1016/j.radcr.2020.11.048

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Objective Coronary plaques with low attenuation on computed tomography (CT) angiography may indicate vulnerable plaques. However, plaque CT attenuation is reported to be significantly affected by intracoronary attenuation. Recently, the diluted-contrast injection protocol was established to facilitate more uniform intracoronary attenuation than can be achieved with the generally used body-weight-adjusted protocol. We validated the relationship between low-attenuation plaque on CT and lipid-rich plaque using integrated backscatter-intravascular ultrasound (IB-IVUS) as the standard reference. Methods Plaques were divided into tertiles (T1, T2, and T3) according to the plaque CT attenuation, calculated as the average of five intra-plaque regions of interest, and compared with the plaque characteristics noted on IB-IVUS. Patients Patients who underwent both CT angiography using a diluted-contrast injection protocol and IB-IVUS were retrospectively analyzed. Results Thirty-nine plaques in 32 patients were analyzed by CT angiography and IB-IVUS. The median plaque CT attenuation (Hounsfield units) of each tertile was 30 (T1), 48 (T2), and 68 (T3). Although no significant difference was noted in conventional quantitative IVUS parameters (e.g. plaque burden), the T1 with lowest plaque CT attenuation had the highest percentage lipid area by IB-IVUS [75.1% (T1), 57.8% (T2), and 50.8% (T3), respectively, p<0.01]. Furthermore, the plaque CT attenuation had a significant negative correlation with the percentage lipid area (r=-0.59, p<0.01). Conclusion CT angiography-based plaque characterization using a diluted-contrast injection protocol may aid in the quantitative detection of lipid-rich plaque.

DOI： 10.2169/internalmedicine.6683-20

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BACKGROUND: Cardiovascular magnetic resonance (CMR) late gadolinium enhancement (LGE) is a valuable technique for detecting myocardial disorders and fibrosis. However, we sometimes observe a linear, mid-wall high intensity signal in the basal septum in the short axis view, which often presents diagnostic difficulties in the clinical setting. The purpose of this study was to compare the linear, mid-wall high intensity in the basal septum identified by LGE with the anterior septal perforator arteries identified by coronary computed tomography angiography (CorCTA). METHODS: We retrospectively selected 148 patients who underwent both CorCTA and CMR LGE within 1 year. In the interpretation of LGE, we defined a positive linear high intensity (LHI+) as follows: ① LHI in the basal septum and ② observable for 1.5 cm or more. All other patients were defined as a negative LHI (LHI-). In LHI+ patients, we assessed the correlation between the LHI length and the septal perforator artery length on CorCTA. We also compared the length of the septal perforator artery on CorCTA between LHI+ patients and LHI- patients. RESULTS: A population of 111 patients were used for further analysis. Among these , there were 55 LHI+ patients and 56 LHI- patients. In LHI+ patients, linear regression analysis revealed that there was a good agreement between LGE LHI and septal perforator arteries by CorCTA in terms of length measurements. The measured length of the anterior septal perforator arteries was significantly shorter in LHI- patients than in LHI+ patients (10 ± 8 mm vs. 21 ± 8 mm; P < 0.05). CONCLUSIONS: The LHI observed in the basal septum on short axis LGE may reflect contrast enhancement of the anterior septal perforator arteries. It is important to interpret this septal LHI against knowledge of anatomic structure, to avoid misinterpretations of LGE and prevent misdiagnosis.

DOI： 10.1186/s12968-020-00665-5

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PURPOSE: This study aimed to compare the efficacy of compressed sensing (CS) and conventional coronary magnetic resonance angiography (CMRA) in detecting coronary artery stenosis. METHOD: Twenty-eight patients underwent 3 T contrast-enhanced CS and conventional CMRA; for late gadolinium enhancement (LGE) imaging, 0.1 mmol/kg gadolinium medium was infused. CS CMRA was scanned within the LGE waiting time. After the LGE image acquisition, conventional CMRA was performed. The diagnostic performance of both CMRA for the detection of significant stenosis was evaluated using coronary angiography as a reference. The analysis was conducted to examine the three main coronary artery vessels: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA). These arteries were subdivided into 8 segments (LAD; main, proximal, and middle, LCX; proximal and distal, RCA; proximal, middle, and distal). Of these, hypoplastic segments and vessels after coronary stent implantation were excluded. The acquisition time of CS CMRA was compared with that of conventional CMRA. RESULTS: The coronary arteries were evaluated in 197 segments. The sensitivity, specificity, and accuracy of CS CMRA in detecting significant stenosis were 85.2 %, 82.5 %, and 83.2 %, respectively, on a per-segment basis. Those of conventional CMRA were 85.2 %, 86.7 %, and 86.3 %, respectively. The acquisition time was 207 s (range, 144-258 s) for CS and 975 s (range, 787-1226s) for conventional CMRA (p < 0.001). CONCLUSIONS: Similar to conventional CMRA, CS CMRA has shown potential for the detection of significant coronary artery stenosis.

DOI： 10.1016/j.ejrad.2020.109124

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OBJECTIVES: This study evaluated the characteristics of left ventricular maximum principal strain (LV-MPS) using cardiac CT in subjects with normal LV function. METHODS: Of 973 subjects who underwent retrospective electrocardiogram-gated cardiac CT using a third-generation dual-source CT without beta-blocker administration, 31 subjects with preserved LV ejection fraction ≥ 55% assessed by echocardiography without coronary artery stenosis and cardiac pathology were retrospectively identified. CT images were reconstructed every 5% (0-95%) of the RR interval. LV-MPS and the time to peak (TTP) were analyzed using the 16-segment model and compared among three levels (base, mid, and apex) and among four regions (anterior, septum, inferior, and lateral) using the Steel-Dwass test. The intra- and inter-observer reproducibilities for LV-MPS were calculated using intraclass correlation coefficients (ICCs). RESULTS: The intra- and inter-observer ICCs (95% confidence interval) for peak LV-MPS were 0.96 (0.94-0.97) and 0.94 (0.92-0.96), respectively. The global peak LV-MPS (median, inter-quantile range) was 0.59 (0.55-0.72). The regional LV-MPS significantly increased in the order of the basal (0.54, 0.49-0.59), mid-LV (0.57, 0.53-0.65), and apex (0.68, 0.60-0.84) (p < 0.05, in each), and was significantly higher in the lateral wall (0.66, 0.60-0.77), while that in the septal region (0.47, 0.44-0.54) was the lowest among the four LV regions (all p < 0.05). No significant difference in TTP was seen among the myocardial levels and regions. CONCLUSION: CT-derived LV-MPS is reproducible and quantitatively represents synchronized myocardial contraction with heterogeneous values in subjects with normal LV function. KEY POINTS: • CT-derived left ventricular maximum principal strain analysis allows highly reproducible quantitative assessments of left ventricular myocardial contraction. • In subjects with normal cardiac function, the peak value of CT-derived left ventricular maximum principal strain is the highest in the apical level and in the lateral wall and the lowest in the septum. • The regional peak left ventricular maximum principal strain shows intra-ventricular heterogeneity on a per-patient basis, but myocardial contraction is globally synchronized in subjects with normal cardiac function seen on cardiac CT.

DOI： 10.1007/s00330-020-07001-6

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We aimed to evaluate the effects of four-dimensional noise reduction filtering using a similarity algorithm (4D-SF) on the image quality and hemodynamic parameter of dynamic myocardial computed tomography perfusion (CTP). Sixty-eight patients who underwent dynamic myocardial CTP for the assessment of coronary artery disease were enrolled. Dynamic CTP was performed using a 320-row CT with low tube voltage scan (80 kVp). Two different datasets of dynamic CTP were reconstructed using iterative reconstruction (IR) alone and a combination of IR and 4D-SF. Qualitative (5-grade scale) and quantitative image quality scores were assessed, and the CT-derived myocardial blood flow (CT-MBF) was quantified. These results were compared between the two different CTP images. The qualitative image quality in CTP images reconstructed with IR and 4D-SF was significantly higher than that with IR alone (noise score: 4.7 vs. 3.4, p < 0.05). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in CTP images reconstructed with IR and 4D-SF were significantly higher than those with IR alone (SNR: 20.6 vs. 9.7; CNR: 7.9 vs. 3.9, respectively; p < 0.05). There was no significant difference in mean CT-MBF between the two sets of CTP images (3.01 vs. 3.03 mL/g/min, p = 0.1081). 4D-SF showed incremental value in improving image quality in combination with IR without altering CT-MBF quantification in dynamic myocardial CTP imaging with a low tube potential.

DOI： 10.1007/s10554-020-01878-6

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AIM: To evaluate the utility of synthetic magnetic resonance imaging (MRI) of the breast in predicting the Ki-67 status in patients with oestrogen receptor (ER)-positive breast cancer. MATERIALS AND METHODS: Forty-nine patients with 50 histopathologically proven breast cancers who underwent additional synthetic MRI were enrolled in the present study. Using synthetic MRI images, T1 and T2 relaxation times and their standard deviations (SD) in the breast lesions before (T1-Pre, T2-Pre, PD-Pre, SD of T1-Pre, SD of T2-Pre, SD of PD-Pre) and after (T1-Gd, T2-Gd, PD-Gd, SD of T1-Gd, SD of T2-Gd, SD of PD-Gd) contrast agent injection were obtained. These quantitative values were compared between the low Ki-67 expression (&lt
14%) lesions (low-proliferation group: n=23) and high Ki-67 expression (≥14%) lesions (high-proliferation group: n=27). RESULTS: The univariate analysis showed that the SD of T1-Gd (p&lt
0.001) and T2-Gd (p=0.042) were significantly higher in the high-proliferation group than in the low-proliferation group. Multivariate analysis further showed that the SD of T1-Gd was a significant and independent predictor of Ki-67 expression, with an area under the receiver operating characteristic (AUROC) curve of 0.885. The sensitivity, specificity, and accuracy of the SD of T1-Gd with an optimal cut-off value of 98.5 were 77.8%, 87%, and 82%, respectively. CONCLUSION: The SD of T1-Gd obtained from synthetic MRI was useful to predict Ki-67 status.

DOI： 10.1016/j.crad.2019.12.021

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Myocardial ischemia is caused by a mismatch between myocardial oxygen consumption and oxygen delivery in coronary artery disease (CAD). Stratification and decision-making based on ischemia improves the prognosis in patients with CAD. Non-invasive tests used to evaluate myocardial ischemia include stress electrocardiography, echocardiography, single-photon emission computed tomography, and magnetic resonance imaging. Invasive fractional flow reserve is considered the reference standard for assessment of the hemodynamic significance of CAD. Computed tomography (CT) angiography has emerged as a first-line imaging modality for evaluation of CAD, particularly in the population at low to intermediate risk, because of its high negative predictive value; however, CT angiography does not provide information on the hemodynamic significance of stenosis, which lowers its specificity. Emerging techniques, e.g., CT perfusion and CT-fractional flow reserve, help to address this limitation of CT, by determining the hemodynamic significance of coronary artery stenosis. CT perfusion involves acquisition during the first pass of contrast medium through the myocardium following pharmacological stress. CT-fractional flow reserve uses computational fluid dynamics to model coronary flow, pressure, and resistance. In this article, we review these two functional CT techniques in the evaluation of myocardial ischemia, including their principles, technology, advantages, limitations, pitfalls, and the current evidence.

DOI： 10.1007/s11604-020-00922-8

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BACKGROUND: This study aimed to evaluate the combined diagnostic performance of coronary artery stenosis-subtended myocardial volume (Vsub) and myocardial blood flow (MBFsub) on computed tomography (CT) for detecting obstructive coronary artery disease (CAD) assessed by invasive coronary angiography (ICA) and fractional flow reserve (FFR). METHODS: Thirty-nine patients who underwent coronary CT angiography (CTA) and stress dynamic myocardial CT perfusion (CTP) prior to ICA were enrolled. Obstructive CAD was defined as severe (≥70%) or moderate (30-69%) stenosis with FFR ≤0.8 on ICA. The Vsub was semi-automatically calculated from coronary CTA data using Voronoi diagram-based myocardial segmentation. The standard CT-MBF based on the 17-segment model was calculated using dynamic stress CTP data and deconvolution analysis. The CT-MBFsub was automatically analyzed by integrating the CT-MBF and Voronoi diagram-based myocardial segmentation analyses. The diagnostic performance of combined CT-MBFsub and Vsub assessment was determined using receiver operating characteristic analysis and compared with standard CT-MBF and CT-MBFsub. RESULTS: Of 117 vessels in 39 patients, 72 vessels were suspected of significant stenosis on CTA and 33 vessels had obstructive CAD on ICA and FFR. The sensitivity and specificity for identifying obstructive CAD were 67% and 82% for standard CT-MBF, 70% and 77% for CT-MBFsub, and 85% and 82% for combined CT-MBFsub and Vsub assessment. The area under the receiver operating characteristic curve of the combined CT-MBFsub and Vsub assessment was significantly higher than those of standard CT-MBF and CT-MBFsub (0.89 vs. 0.75, 0.77; p<0.05). CONCLUSIONS: The Vsub may aid in increasing the diagnostic performance of CT-MBFsub for detecting obstructive CAD.

DOI： 10.1016/j.jjcc.2020.03.006

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BACKGROUND: Our aim was to evaluate the ability of adenosine triphosphate (ATP)-stress myocardial computed tomography perfusion (CTP) imaging to detect myocardial ischemia in the left anterior descending artery (LAD) territory, and to compare this method with coronary flow velocity reserve (CFVR) measured by transthoracic Doppler echocardiography (TTDE). METHODS: ATP-stress CTP and CFVR were performed in 50 patients with stable angina pectoris. Myocardial ischemia assessed from CTP imaging was defined as qualitative visual perfusion defects and reduced myocardial blood flow (MBF) based on quantitative assessment. A cut-off value of CFVR of 2.0 was used. RESULTS: The mean CFVR was 1.9 ± 0.6 in ischemic regions by CTP, whereas it was 2.9 ± 0.8 in non-ischemic regions (p < 0.001). CTP imaging could accurately predict CFVR <2.0 with 84.0% diagnostic accuracy (94.7% sensitivity, 77.4% specificity, 72.0% positive predictive value, and 96.0% negative predictive value). When receiver operating characteristic curve analysis of the MBF data was performed to detect CFVR <2.0, the area under the curve was 0.89, and the optimal MBF cut-off value was 1.43 mL/g/min. CONCLUSIONS: This study suggests that qualitative and quantitative assessment of ATP-stress CTP exhibits a good correlation with CFVR for evaluation of myocardial ischemia.

DOI： 10.1016/j.jjcc.2020.03.003

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BACKGROUND: Although coronary computed tomography angiography (CTA) is frequently used for identifying coronary artery disease, no studies have investigated the radiation dose in detail in Japan. The aim of this study was to estimate the radiation dose of coronary CTA in Japanese clinical practice and to identify the independent predictors associated with radiation dose.Methods and Results:A multicenter, retrospective, observational study (54 institutions) was conducted for estimating the radiation dose of coronary CTA in 2,469 patients between January and December 2013. Independent predictors associated with radiation dose were investigated on linear regression analysis. Median dose-length product (DLP) was 809.0 mGy·cm (IQR, 350.0-1,368.8 mGy·cm), corresponding to an estimated radiation dose of 11 mSv. The DLP per site significantly differed between institutions (median DLP per site, 92-2,131 mGy·cm; P<0.05). Independent predictors associated with radiation dose on multivariable linear regression were body weight, heart rate, non-stable sinus rhythm, scan length, tube voltage setting, electrocardiogram (ECG)-gated scanning protocol, and the image reconstruction technique (P<0.05 each). CONCLUSIONS: The coronary CTA radiation dose was relatively high in 2013, and it varied significantly between institutions. Effective strategies for radiation dose reduction were low tube voltage ≤100 kVp, retrospective ECG-gated scanning with dose modulation technique, prospective ECG-gated scanning, and the iterative reconstruction technique.

DOI： 10.1253/circj.CJ-19-0843

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BACKGROUND: Coronary magnetic resonance angiography (CMRA) is a promising technique for assessing the coronary arteries. However, a disadvantage of CMRA is the comparatively long acquisition time. Compressed sensing (CS) can considerably reduce the scan time. The aim of this study was to verify the feasibility of CS CMRA scanning during the waiting time between contrast injection and late gadolinium enhancement (LGE) scan in a clinical protocol. METHODS: Fifty clinical patients underwent contrast-enhanced CS CMRA and conventional CMRA on a 3 T CMR scanner. After contrast injection, CS CMRA was scanned during the waiting time for LGE CMR. A conventional CMRA scan was performed after LGE CMR. We assessed acquisition times and coronary artery image quality for each segment on a 4-point scale. Visible vessel length, sharpness and diameter of right (RCA), left anterior descending (LAD), and left circumflex (LCX) coronary arteries were also quantitatively compared among the scans. RESULTS: All CS CMRA scans were successfully performed within the LGE waiting time. The median total scan time was 207 s (163, 259 s) for CS and 785 s (698, 975 s) for conventional CMRA (p < 0.001). No significant differences were observed in image quality scores, vessel length measurements, sharpness, and diameter between CS and conventional CMRA. CONCLUSIONS: We could achieve all CS CMRA scans within the LGE waiting time. Contrast-enhanced CS CMRA could considerably shorten the scan time while maintaining image quality compared with conventional CMRA.

DOI： 10.1186/s12968-020-0601-0

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RATIONALE AND OBJECTIVES: Fractional flow reserve (FFR) is an established technique for detecting lesion-specific ischemia but is invasive. Our objective was to investigate the effects of combined assessment of coronary CT angiography (CCTA) imaging features and CT-FFR on detecting lesion-specific ischemia by comparing with invasive FFR. MATERIALS AND METHODS: Forty-seven patients who had 60 coronary vessels with 30%-90% stenosis were included. Six anatomic CCTA descriptors (Agatston score, stenosis severity, mean plaque CT attenuation value, noncalcified and calcified plaque volumes, remodeling index) and a functional descriptor (CT-FFR) were measured. Random forest was used to identify which descriptors were useful to identify ischemia-related lesion. Receiver-operating characteristic (ROC) curves were calculated for 2 models: i.e. Model-1 for anatomical CT descriptors and Model-2 for anatomical CT descriptors plus CT-FFR. RESULTS: Stenosis severity (40.8 ± 15.7% vs 57.6 ± 14.1%), noncalcified plaque volume (190 ± 100 vs 254.8 ± 133.3), and remodeling index (1.04 ± 0.12 vs 1.11 ± 0.13) were significantly higher in ischemia-related lesions than nonischemia-related lesions. CT-FFR was 0.84 ± 0.14 and 0.71 ± 0.14, respectively, for ischemia-related and nonischemia-related lesions, and the difference was significant. The area under the ROC curve was 0.738 and 0.835 in Model-1 and Model-2, respectively. Reclassification of ischemic lesion risk was significantly improved after adding CT-FFR: net reclassification improvement was 0.297 and integrated discrimination improvement was 0.254. CONCLUSION: Combined assessment of anatomical CCTA features and functional CT-FFR was helpful for detecting lesion-specific ischemia.

DOI： 10.1016/j.acra.2019.12.013

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PURPOSE: To evaluate the image quality and lesion visibility of virtual monoenergetic images (VMIs) reconstructed using a new monoenergetic reconstruction algorithm (nMERA) for evaluation of breast cancer. MATERIALS AND METHODS: Forty-two patients with 46 breast cancers who underwent 4-phasic breast contrast-enhanced computed tomography (CT) using dual-energy CT (DECT) were enrolled. We selected the peak enhancement phase of the lesion in each patient. The selected phase images were generated by 120-kVp-equivalent linear blended (M120) and monoenergetic reconstructions from 40 to 80 keV using the standard reconstruction algorithm (sMERA: 40, 50, 60, 70, 80) and nMERA (40 +, 50 +, 60 +, 70 +, 80 +). The contrast-to-noise ratio (CNR) was calculated and objectively analyzed. Two independent readers subjectively scored tumor visibility and image quality each on a 5-point scale. RESULTS: The CNR at 40 + and tumor visibility scores at 40 + and 50 + were significantly higher than those on M120. The CNR at 50 + was not significantly different from that on M120. However, the overall image quality score at 40 + was significantly lower than that at 50 + and on M120 (40 + vs M120, P < 0.0001 and 40 + vs 50 +, P = 0.0001). CONCLUSIONS: VMI reconstructed with nMERA at 50 keV is preferable for evaluation of patients with breast cancer.

DOI： 10.1007/s11604-019-00897-1

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BACKGROUND: This study evaluated corrected relative flow reserve (RFR) derived from 13N-ammonia positron emission tomography (PET) combined with coronary computed tomography angiography (CTA). METHODS: We analyzed 61 patients who underwent coronary CTA, 13N-ammonia PET, and invasive coronary angiography. Triple-vessel disease were excluded. Conventional RFRs were calculated as the ratio of hyperemic myocardial blood flow (hMBF) of hypoperfusion areas to those of non-ischemic lesions. Corrected RFRs were calculated using PET and coronary CTA to adjust coronary territories to their feeding vessels. Diagnostic performance was compared to detect obstructive coronary lesions. RESULTS: Of the 180 vessels analyzed, 50 were diagnosed as obstructive lesions (≥ 70% stenosis and/or fractional flow reserve value ≤ 0.8). The coronary flow reserve (CFR), hMBF, conventional RFR, and corrected RFR of obstructive lesions were significantly lower than those of non-obstructive lesions. In receiver operating characteristic curve analysis, these quantitative PET measurements had area under the curve of 0.67, 0.71, 0.89, and 0.92, respectively. Diagnostic performance differences between corrected and conventional RFR were not statistically significant. CONCLUSION: In patients with single or double vessel disease, indices of RFR, with or without coronary angiographic guidance of the reference coronary territory, are better discriminators of flow-limiting stenoses than hMBF and CFR.

DOI： 10.1007/s12350-019-01931-5

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The purpose of this study was to evaluate the feasibility of the stenosis-related quantitative perfusion ratio (QPR) for detecting hemodynamically significant coronary artery disease (CAD). Twenty-seven patients were retrospectively enrolled. All patients underwent dynamic myocardial computed tomography perfusion (CTP) and coronary computed tomography angiography (CTA) before invasive coronary angiography (ICA) measuring the fractional flow reserve (FFR). Coronary lesions with FFR ≤ 0.8 were defined as hemodynamically significant CAD. The myocardial blood flow (MBF) was calculated using dynamic CTP data, and CT-QPR was calculated as the CT-MBF relative to the reference CT-MBF. The stenosis-related CT-MBF and QPR were calculated using Voronoi diagram-based myocardial segmentation from coronary CTA data. The relationships between FFR and stenosis-related CT-MBF or QPR and the diagnostic performance of the stenosis-related CT-MBF and QPR were evaluated. Of 81 vessels, FFR was measured in 39 vessels, and 20 vessels (51%) in 15 patients were diagnosed as hemodynamically significant CAD. The stenosis-related CT-QPR showed better correlation (r = 0.70, p < 0.05) than CT-MBF (r = 0.56, p < 0.05). Sensitivity and specificity for detecting hemodynamically significant CAD were 95% and 58% for CT-MBF, and 95% and 90% for CT-QPR, respectively. The area under the receiver operating characteristic curve for the CT-QPR was significantly higher than that for the CT-MBF (0.94 vs. 0.79; p < 0.05). The stenosis-related CT-QPR derived from dynamic myocardial CTP and coronary CTA showed a better correlation with FFR and a higher diagnostic performance for detecting hemodynamically significant CAD than the stenosis-related CT-MBF.

DOI： 10.1007/s12928-019-00627-4

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：NLM (Medline)  

OBJECTIVE: Knowledge-based iterative model reconstruction (IMR) yields diagnostically acceptable image quality in low-dose static computed tomography (CT). We aimed to evaluate the feasibility of IMR in dynamic myocardial computed tomography perfusion (CTP). METHODS: We enrolled 24 patients who underwent stress dynamic CTP using a 256-slice CT. Images were reconstructed using filtered back projection (FBP), hybrid IR, and IMR. Image quality and hemodynamic parameters were compared among three algorithms. RESULTS: Qualitative image quality and contrast-to-noise ratio were significantly higher by IMR than by FBP or hybrid IR (visual score: 4.1 vs. 3.0 and 3.5
contrast-to-noise ratio: 12.4 vs. 6.6 and 8.4
P &lt
0.05). No significant difference was observed among algorithms in CTP-derived myocardial blood flow (1.68 vs. 1.73 and 1.70 mL/g/min). CONCLUSIONS: The use of knowledge-based iterative model reconstruction improves image quality without altering hemodynamic parameters in low-dose dynamic CTP, compared with FBP or hybrid IR.

DOI： 10.1097/RCT.0000000000000914

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BACKGROUND: This study evaluated the diagnostic capability of on-site coronary computed tomography-derived computational fractional flow reserve (CT-FFR) determinations for detecting coronary artery disease (CAD), as assessed by invasive fractional flow reserve (FFR).Methods and Results:Seventy-four patients with coronary artery calcium scores <1,500 who underwent coronary CT angiography (CTA) and invasive FFR measurements within 90 days were retrospectively reviewed. CT-FFR was computed using a prototype machine-learning (ML) algorithm in 91 vessels; 47 vessels of 42 patients were determined to have significant CAD (FFR ≤0.8). Correlation between CT-FFR and FFR was good (r=0.786, P<0.001). Per-vessel area under the curve was significantly larger for CT-FFR (0.907, 95% confidence interval: 0.828-0.958) than for CTA stenosis ≥50% (0.595, 0.487-0.697) or ≥70% (0.603, 0.495-0.705) (both P<0.001). Standard coronary CTA classifications recommended further functional tests in 57 patients with moderate or worse stenosis on CTA. CT-FFR analysis (mean analysis time: 16.4±7.5 min) corrected the standard coronary CTA classification in 18 of 74 patients and confirmed it in 45 of 74 patients. Thus, the per-patient diagnostic accuracy of the classifications was improved from 66% (54-77%) to 85% (75-92%). CONCLUSIONS: On-site CT-FFR based on a ML algorithm can provide good diagnostic performance for detecting hemodynamically significant CAD, suggesting the high value of coronary CTA for selected patients in clinical practice.

DOI： 10.1253/circj.CJ-19-0163

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BACKGROUND: Direct evidence of inflammatory activity in the atria of patients with atrial fibrillation (AF) is scarce. We assessed the capability of positron-emission tomography/computed tomography (PET/CT) to diagnose AF based on fluorodeoxyglucose (FDG) uptake in the atrial wall. METHODS AND RESULTS: Among 8233 patients who underwent FDG-PET/CT as work-up for malignancies, we identified 180 consecutive patients with AF (2.2%). Of those, we selected 137 patients who had fasted >12 h before FDG injection for inclusion in the experimental group (88 men and 49 women; age: 72.7 ± 8.9 years). Controls were 62 age- and sex-matched patients without AF. For visual analysis, we used a 4-point grading system. For quantitative analysis, we used the maximum standard uptake value (SUVmax) in the left (LA) and right atrial (RA) myocardium and the target-to-background ratio (TBR) of SUVmax to blood pool activity. The sensitivity, specificity, and positive-predictive value for detecting AF visually were 54.0%, 95.2%, and 96.1%, respectively; for quantitative analysis, the respective values were 65.7%, 75.8%, and 85.7%. Multivariable analysis of 11 clinical and imaging variables showed significant associations with RA SUVmax (odds ratio [OR]: 14.353, P = 0.026) and LA volume (OR: 1.371, P = 0.0001). The RA TBR was greater in cases with persistent AF than in those with paroxysmal AF (P < 0.0001). Pathological investigation of 4 autopsy hearts confirmed infiltration of extravascular macrophages and lymphocytes in the regions with FDG uptake. CONCLUSIONS: Higher atrial FDG uptake was associated with AF. PET/CT could be a useful tool for detecting local inflammation in the atria with AF.

DOI： 10.1016/j.ijcard.2018.10.106

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BACKGROUND: This study aimed to evaluate the incremental diagnostic value of dynamic myocardial computed tomography (CT) perfusion (CTP) imaging for detecting obstructive coronary artery disease (CAD) in comparison with coronary CT angiography (CTA). METHODS: Thirty-eight patients who had undergone coronary CTA and pharmacological stress dynamic CTP before invasive coronary angiography (ICA) were selected retrospectively. Using ICA, obstructive CAD was defined as the presence of severe (≥70%) or moderate (50-69%) stenosis with fractional flow reserve (FFR) <0.75. For CT evaluations, coronary vessels with any stenosis ≥50%, ≥70% or unassessable lesions were considered significantly stenotic. Dynamic CTP was assessed quantitatively using CT-derived myocardial blood flow (CT-MBF). Receiver operating characteristic (ROC) curve analysis determined the cut-off value of CT-MBF for identifying obstructive CAD. The diagnostic performances of CTA alone and integrated CTA and CTP assessments for detecting obstructive CAD were compared. RESULTS: Using ICA and FFR, 24 of 114 vessels had obstructive CAD. The cut-off value of CT-MBF for detecting obstructive CAD was 1.26mL/g/min. The sensitivity, specificity, and positive and negative predictive values (PPV and NPV) at the vessel level were 96%, 57%, 37%, and 98% for CTA, and 83%, 93%, 77%, and 95% for integrated CTA and CTP assessment using cut-off 50% stenosis on CTA, respectively. The sensitivity, specificity, and PPV and NPV at the vessel level were 79%, 69%, 40%, and 93% for CTA, and 71%, 97%, 85%, and 93% for integrated CTA and CTP assessment using cut-off 70% stenosis on CTA, respectively. The area under the ROC curve for CTA and CTP was significantly higher than that for CTA alone (0.96 vs. 0.84, p<0.05). CONCLUSIONS: Stress dynamic myocardial CTP is feasible to detect hemodynamically obstructive CAD in patients with high pre-test likelihood and helps for improving diagnostic performance in comparison with coronary CTA alone.

DOI： 10.1016/j.jjcc.2018.12.006

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DOI： 10.1016/j.clinimag.2019.03.016

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Language：English   Publisher：(一社)日本循環器学会  

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OBJECTIVES: Whole-heart coronary magnetic resonance angiography (MRA) is a promising non-contrast, radiation-free technique for assessing the coronary artery. Yet, a disadvantage of coronary MRA is the relatively long acquisition time. The purpose of this study was to evaluate the scan time and image quality of compressed sensing (CS) coronary MRA compared with conventional coronary MRA. MATERIALS AND METHODS: Twenty healthy volunteers underwent navigator-gated coronary MRA with a CS prototype sequence and conventional navigator-gated coronary MRA on a clinical 3T MRI scanner without contrast medium. The spatial resolutions were 1.33 × 1.33 × 1.20 mm3 for CS and 1.33 × 1.33 × 1.48 mm3 interpolated to 0.70 × 0.70 × 1.20 mm3 for conventional, respectively. We compared acquisition times, rated image quality on a 4-point scale (RCA; proximal, middle, and distal, LAD; main, proximal, middle, and distal, LCX; proximal and distal), and measured the visualized vessel lengths of three vessels. RESULTS: The mean acceptance rates were 44.9% for CS coronary MRA and 48.7% for conventional coronary MRA (p = .39). The mean effective scan time was 3 min 45 s for CS coronary MRA and 15 min 6 s for conventional coronary MRA (p < 0.001). Image quality scores were significantly lower for CS coronary MRA than for conventional coronary MRA (3.4 ± 0.7 for CS vs. 3.8 ± 0.4 for conventional; p < 0.0001). Conventional coronary MRA images were scored >3.4 in all segments on average, while CS coronary MRA images were scored >3.2 (good quality for diagnosis) in almost all segments, with only the distal RCA segment graded 2.9 on average. The average visible vessel lengths for CS and conventional coronary MRA were as follows: 11.5 ± 4.4 cm and 12.5 ± 4.8 cm for the RCA, respectively (p < 0.05, 95% limits of agreement [LOA]; -3.6 to 1.6 cm); 10.6 ± 3.0 cm and 11.1 ± 2.9 cm for the LAD, respectively (p = .15, 95% LOA -4.0 to 2.8 cm); and 7.1 ± 2.2 cm and 8.2 ± 2.5 cm for the LCX, respectively (p < 0.05, 95% LOA -4.0 to 1.7 cm). CONCLUSIONS: Non-contrast coronary MRA using CS could largely shorten acquisition time, compared with conventional navigator-gated coronary MRA, while maintaining acceptable visualization at 3T.

DOI： 10.1016/j.ejrad.2018.04.025

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PURPOSE: We evaluated the associations between gestational age (GA) and lung-to-liver signal intensity ratio (LLSIR) and fetal lung volume (FLV) using magnetic resonance imaging (MRI). Moreover, we evaluated the reproducibility of these measurements. MATERIALS AND METHODS: LLSIR and FLV were measured using single-shot fast spin-echo MRI in 88 consecutive fetuses. The Spearman test was used to assess the relationships between (1) LLSIR and GA, and (2) FLV and GA in 81 fetuses without lung abnormalities. Intra- and inter-observer reliabilities were assessed using intra-class correlation coefficients (ICCs). RESULTS: Overall, GA and LLSIR were significantly correlated (r = 0.62, p < 0.001). However, GA and LLSIR were only significantly correlated during the third trimester (before third trimester: r = 0.39, p = 0.08; during third trimester: r = 0.46, p < 0.001). Overall, GA and FLV were significantly correlated (r = 0.72, p < 0.001). FLV was significantly correlated with GA before (r = 0.86, p < 0.001) and during the third trimester (r = 0.47, p < 0.001). All ICCs were above 0.90. CONCLUSIONS: LLSIR and FLV are useful for the assessment of fetal lung maturity and are highly reproducible. Before the third trimester, FLV is more suitable than LLSIR for the evaluation of fetal lung maturity.

DOI： 10.1007/s11604-018-0745-0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Verlag  

Objective: To evaluate the feasibility of image subtraction in late iodine enhancement CT (LIE-CT) for assessment of myocardial infarction (MI). Methods: A comprehensive cardiac CT protocol and late gadolinium enhancement MRI (LGE-MRI) was used to assess coronary artery disease in 27 patients. LIE-CT was performed after stress CT perfusion (CTP) and CT angiography. Subtraction LIE-CT was created by subtracting the mask volume of the left ventricle (LV) cavity from the original LIE-CT using CTP dataset. The %MI volume was quantified as the ratio of LIE to entire LV volume, and transmural extent (TME) of LIE was classified as 0%, 1–24%, 25–49%, 50–74% or 75–100%. These results were compared with LGE-MRI using the Spearman rank test, Bland-Altman method and chi-square test. Results: One hundred twenty-five (29%) of 432 segments were positive on LGE-MRI. Correlation coefficients for original and subtraction LIE-CT to LGE-MRI were 0.79 and 0.85 for %MI volume. Concordances of the 5-point grading scale between original and subtraction LIE-CT with LGE-MRI were 75% and 84% for TME
concordance was significantly improved using the subtraction technique (p &lt
0.05). Conclusion: Subtraction LIE-CT allowed more accurate assessment of MI extent than the original LIE-CT. Key Points: • Subtraction LIE-CT allows for accurate assessment of the extent of myocardial infarction. • Subtraction LIE-CT shows a close correlation with LGE-MRI in %MI volume. • Subtraction LIE-CT has significantly higher concordance with TME assessment than original LIE-CT.

DOI： 10.1007/s00330-017-5048-9

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To assess a two-phase contrast injection protocol for contrast enhancement during cardiac computed tomography (CT) in children with congenital heart disease. Forty-three children (20 boys, 23 girls) of median age 13 months (range 3 days-8.3 years) and weighing ≤ 20 kg who underwent cardiac CT using a two-phase contrast injection protocol at our institution were retrospectively identified. High-pitch spiral third-generation dual-source cardiac CT (tube voltage 70 kV) was performed with a fixed delay of 60 s after contrast injection in the order of 10 mgI/kg/s (30 s), 15 mgI/kg/s (20 s), and a saline chaser (10 s). Attenuation in the inferior vena cava (IVC), superior vena cava (SVC), right atrium (RA), right ventricle (RV), pulmonary artery (PA), left atrium (LA), left ventricle (LV), and descending aorta (AO) was compared using the Steel-Dwass and Fisher's exact tests. The median (interquartile range) attenuation in the IVC, SVC, RA, RV, PA, LA, LV, and AO was 285 (264-347) Hounsfield units (HU), 416 (370-445) HU, 368 (320-388) HU, 373 (322-417) HU, 397 (330-432) HU, 425 (373-469) HU, 435 (385-468) HU, and 437 (392-491) HU, respectively (p < 0.05, IVC vs. the other anatomic sites). There was no significant difference in diagnostic success rate for attenuation > 250 HU between the IVC (41 children, 95.3%) and the other sites (43 children, 100%). A two-phase contrast injection protocol is useful for effective contrast enhancement in pediatric cardiac CT.

DOI： 10.1007/s00246-017-1782-7

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Publishing type：Research paper (scientific journal)   Publisher：Ovid Technologies (Wolters Kluwer Health)  

DOI： 10.1097/rct.0000000000000752

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Birt-Hogg-Dubé syndrome (BHD) is a rare autosomal dominant disease characterized by skin fibrofolliculomas, pulmonary cysts, spontaneous pneumothoraces, and renal cancers. Oncocytomas are benign epithelial tumors that are also rare. Recently, there have been a few case reports of BHD with a parotid oncocytoma that appears to have a BHD phenotype. Here we document the eighth known case and describe the magnetic resonance imaging features of the parotid oncocytoma, which mimicked Warthin's tumor. Radiologists should be aware of the association between these rare disorders.

DOI： 10.1155/2018/6265175

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCIENCE BV  

Background: This study aimed to evaluate the feasibility of peak enhancement (PE) ratio of myocardium to aorta (PER) derived from stress dynamic computed tomography myocardial perfusion imaging (CTP) for the detection of myocardial ischemia assessed by magnetic resonance (MR) imaging.
Methods: Forty-four patients who underwent stress dynamic CTP and MR imaging were retrospectively evaluated. From the time-attenuation curve, myocardial PE, PER, and myocardial blood flow (MBF) were calculated on a segment-based analysis. The correlation between myocardial and aortic PE was assessed by Spearman's correlation, and the differences in myocardial PE and PER between normal and ischemic myocardium were assessed by the Mann-Whitney U-test. The diagnostic accuracies of myocardial PE, PER, and MBF for detecting myocardial ischemia were compared by receiver operating characteristic analysis.
Results: Of 704 segments, 258 segments (37%) were diagnosed as myocardial ischemia with MR imaging. Myocardial and aortic PE were significantly correlated in both normal and ischemic segments (r = 0.76 and 0.58; p &lt; 0.05, in each). The myocardial PE and PER of ischemic segments were significantly lower than those of normal segments (p &lt; 0.05, in each). Sensitivity and specificity were 61% [95% confidence interval (CI), 55-70%] and 83% (95% CI, 73-87%) for myocardial PE, 78% (67-88%) and 82% (95% CI, 70-91%) for PER, and 81% (95% CI, 73-87%) and 85% (95% CI, 79-92%) for MBF. There was a significantly larger area under the curve for PER (0.87; 95% CI, 0.84-0.90) and MBF (0.88; 95% CI, 0.85-0.91), compared to myocardial PE (0.75; 95% CI, 0.70-0.79) (p &lt; 0.05, in each). There was no significant difference in area under the curve between PER and MBF.
Conclusions: The semi-quantitative parameter of PER showed a high diagnostic accuracy for the detection of myocardial ischemia, comparable to that of MBF. (C) 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.jjcc.2017.04.002

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: Compressed sensing (CS) cine magnetic resonance imaging (MRI) has the advantage of being inherently insensitive to respiratory motion. This study compared the accuracy of free-breathing (FB) CS and breath-hold (BH) standard cine MRI for left ventricular (LV) volume assessment.
Methods and Results: Sixty-three patients underwent cine MRI with both techniques. Both types of images were acquired in stacks of 8 short-axis slices (temporal/spatial resolution, 41 ms/1.7x1.7x6 mm3) and compared for ejection fraction, end-diastolic and systolic volumes, stroke volume, and LV mass. Both BH standard and FB CS cine MRI provided acceptable image quality for LV volumetric analysis (score = 3) in all patients (4.7 +/- 0.5 and 3.7 +/- 0.5, respectively; P&lt; 0.0001) and had good agreement on LV functional assessment. LV mass, however, was slightly underestimated on FB CS cine MRI (median, IQR: BH standard, 83.8 mL, 64.7-102.7 mL; FB CS, 79.0 mL, 66.0-101.0 mL; P= 0.0006). The total acquisition times for BH standard and FB CS cine MRI were 113 +/- 7 s and 24 +/- 4 s, respectively (P&lt; 0.0001).
Conclusions: Despite underestimation of LV mass, FB CS cine MRI is a clinically useful alternative to BH standard cine MRI in patients with impaired BH capacity.

DOI： 10.1253/circj.CJ-17-0123

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We evaluated the image quality and diagnostic performance of late iodine enhancement computed tomography (LIE-CT) with knowledge-based iterative model reconstruction (IMR) for the detection of myocardial infarction (MI) in comparison with late gadolinium enhancement magnetic resonance imaging (LGE-MRI). The study investigated 35 patients who underwent a comprehensive cardiac CT protocol and LGE-MRI for the assessment of coronary artery disease. The CT protocol consisted of stress dynamic myocardial CT perfusion, coronary CT angiography (CTA) and LIE-CT using 256-slice CT. LIE-CT scans were acquired 5 min after CTA without additional contrast medium and reconstructed with filtered back projection (FBP), a hybrid iterative reconstruction (HIR), and IMR. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were assessed. Sensitivity and specificity of LIE-CT for detecting MI were assessed according to the 16-segment model. Image quality scores, and diagnostic performance were compared among LIE-CT with FBP, HIR and IMR. Among the 35 patients, 139 of 560 segments showed MI in LGE-MRI. On LIE-CT with FBP, HIR, and IMR, the median SNRs were 2.1, 2.9, and 6.1; and the median CNRs were 1.7, 2.2, and 4.7, respectively. Sensitivity and specificity were 56 and 93% for FBP, 62 and 91% for HIR, and 80 and 91% for IMR. LIE-CT with IMR showed the highest image quality and sensitivity (p &lt; 0.05). The use of IMR enables significant improvement of image quality and diagnostic performance of LIE-CT for detecting MI in comparison with FBP and HIR.

DOI： 10.1007/s10554-017-1137-8

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

Background: Quantitative assessment of myocardial flow reserve (MFR) by single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is challenging but may facilitate evaluation of multi-vessel coronary artery disease (CAD).
Methods: We enrolled 153 patients with suspected or known CAD, referred for pharmacological stress MPI. They underwent a Tc-99m-perfusion stress/rest SPECT with an ultrafast cadmium-zinc-telluride (CZT) camera. Dynamic data were acquired and time-activity curves fitted to a 1-tissue compartment analysis with input function. K1 was assigned for stress and rest data. The MFR index (MFRi) was calculated as K1 stress/K1 at-rest. The findings were validated by invasive coronary angiography in 69 consecutive patients.
Results: The global MFRi was 1.46 (1.16-1.76), 1.33 (1.12-1.54), and 1.18 (1.01-1.35), for 1-vessel disease (VD), 2-VD, and 3-VD, respectively. In the 3-VD, global MFRi was lower than that in 0-VD (1.63 [1.22-2.04], P &lt; 0.0001) and 1-VD (P = 0.003). Multivariate logistic regression analysis for 3-VD showed significant associations with smoking history (odds ratio [OR]: 4.4 [0.4-8.4]), left ventricular ejection fraction (OR: 61.6 [57.5-66.0]), and global MFRi (OR: 119.6 [111.5-127.7], P = 0.002). A cut-off value of 1.3 yielded 93.3% sensitivity and 75.9% specificity for diagnosing 3-VD. Fractional flow reserve positively correlated with regional MFRi (r = 0.62, P = 0.008), and the SYNTAX score correlated negatively with global MFRi (r = 0.567, P = 0.0003).
Conclusion: We developed and validated a clinically available method for MFR quantification by dynamic Tc-99m-perfusion SPECT utilizing a CZT camera, which improves the detectability of multi-vessel CAD. (C) 2017 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.ijcard.2017.06.012

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：W B SAUNDERS CO LTD  

AIM: To examine the diagnostic capabilities of feature-tracking cardiovascular magnetic resonance (FT-CMR), tagged cine magnetic resonance (MR), and wall thickening (WT) analyses to detect infarcted segments in patients with established myocardial infarction (MI).
MATERIALS AND METHODS: Twenty patients with established MI were selected retrospectively and the peak endocardial circumferential strain (CS) was quantified based on the 16-segment model. According to CMR with late gadolinium enhancement, segments were categorised as transmural MI, subendocardial MI, and no MI.
RESULTS: A total of 320 segments (62 transmural MI, 50 subendocardial MI, and 208 no MI) were analysed. Peak endocardial CS was significantly lower for transmural MI compared with subendocardial MI (p &lt; 0.05) and no MI (p &lt; 0.001). Cut-off values of -11.2% for CS by FTCMR, -10.9% for CS by tagged MR, and 23.8% for % WT, differentiated between infarcted and non-infarcted segments with a sensitivity of 72%, 71%, and 56%; specificity of 71%, 75%, and 67%; accuracy of 72%, 73%, and 63%; positive predictive value of 57%, 60%, and 48%; negative predictive value of 83%, 83%, and 74%; and an area-under-the-curve of 0.77, 0.79, and 0.64, respectively.
CONCLUSIONS: FT-CMR was diagnostically superior to % WT, and could differentiate between subendocardial and transmural MI. Unlike tagged MR, FT-CMR did not require the acquisition of additional sequences. (C) 2017 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.crad.2017.05.010

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

To evaluate the feasibility of three-dimensional (3D) maximum principal strain (MP-strain) derived from cardiac computed tomography (CT) for detecting myocardial infarction (MI).
Forty-three patients who underwent cardiac CT and magnetic resonance imaging (MRI) were retrospectively selected. Using the voxel tracking of motion coherence algorithm, the peak CT MP-strain was measured using the 16-segment model. With the trans-mural extent of late gadolinium enhancement (LGE) and the distance from MI, all segments were classified into four groups (infarcted, border, adjacent, and remote segments); infarcted and border segments were defined as MI with LGE positive. Diagnostic performance of MP-strain for detecting MI was compared with per cent systolic wall thickening (%SWT) assessed by MRI using receiver-operating characteristic curve analysis at a segment level.
Of 672 segments excluding16 segments influenced by artefacts, 193 were diagnosed as MI. Sensitivity and specificity of peak MP-strain to identify MI were 81 % [95 % confidence interval (95 % CI): 74-88 %] and 86 % (81-92 %) compared with %SWT: 76 % (60-95 %) and 68 % (48-84 %), respectively. The area under the curve of peak MP-strain was superior to %SWT [0.90 (0.87-0.93) vs. 0.80 (0.76-0.83), p &lt; 0.05].
CT MP-strain has a potential to provide incremental value to coronary CT angiography for detecting MI.
CT MP-strain allows for three-dimensional assessment of regional cardiac function.
CT-MP strain has high diagnostic accuracy for detecting myocardial infarction.
CT-MP strain may assist in tissue characterisation of myocardium assessed by LGE-MRI.
CT-MP strain provides incremental values to coronary CTA for detecting myocardial infarction.

DOI： 10.1007/s00330-016-4550-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

The aim of this study is to assess the effect of blood pressure (BP) on coronary computed tomography angiography (CTA) derived computational fractional flow reserve (CTA-FFR).
Twenty-one patients who underwent coronary CTA and invasive FFR were retrospectively identified. Ischemia was defined as invasive FFR ae&lt;currency&gt;0.80. Using a work-in-progress computational fluid dynamics algorithm, CTA-FFR was computed with BP measured before CTA, and simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg respectively. Correlation between CTA-FFR and invasive FFR was assessed using Pearson test. The repeated measuring test was used for multiple comparisons of CTA-FFR values by simulated BP inputs.
Twenty-nine vessels (14 with invasive FFR ae&lt;currency&gt;0.80) were assessed. The average CTA-FFR for measured BP (134 +/- 20/73 +/- 12 mmHg) was 0.77 +/- 0.12. Correlation between CTA-FFR by measured BP and invasive FFR was good (r = 0.735, P &lt; 0.001). For simulated BPs of 60/50, 90/60, 110/70, 130/80, 150/90, and 180/100 mmHg, the CTA-FFR increased: 0.69 +/- 0.13, 0.73 +/- 0.12, 0.75 +/- 0.12, 0.77 +/- 0.11, 0.79 +/- 0.11, and 0.81 +/- 0.10 respectively (P &lt; 0.05).
Measurement of the BP just before CTA is preferred for accurate CTA-FFR simulation. BP variations in the common range slightly affect CTA-FFR. However, inaccurate BP assumptions differing from the patient-specific BP could cause misinterpretation of borderline significant lesions.
aEuro cent The blood pressure (BP) affects the CTA-FFR computation.
aEuro cent Measured BP before CT examination is preferable for accurate CTA-FFR simulation.
aEuro cent Inaccurate BP assumptions can cause misinterpretation of borderline significant lesions.

DOI： 10.1007/s00330-016-4541-x

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We evaluated the T1 values of segments and slices and the reproducibility in healthy controls, using saturation recovery single-shot acquisition (SASHA) at 3T magnetic resonance imaging. Moreover, we examined the difference in T1 values between hypertrophic cardiomyopathy (HCM) and healthy controls, and compared those with late gadolinium enhancement (LGE).
Twenty-one HCM patients and 10 healthy controls underwent T1 mapping before and after contrast administration. T1 values were measured in 12 segments.
Native T1 values were significantly longer in HCM than in healthy controls [1373 ms (1312-1452 ms) vs. 1279 ms (1229-1326 ms); p &lt; 0.0001]. Even in HCM segments without LGE, native T1 values were significantly longer than in healthy control segments [1366 ms (1300-1439 ms) vs. 1279 ms (1229-1326 ms); p &lt; 0.0001]. Using a cutoff value of 1327 ms for septal native T1 values, we differentiated between HCM and healthy controls with 95% sensitivity, 90% specificity, 94% accuracy, and an area under the curve of 0.95.
Native T1 values using a SASHA at 3T could differentiate HCM from healthy controls. Moreover, native T1 values have the potential to detect abnormal myocardium that cannot be identified adequately by LGE in HCM.

DOI： 10.1007/s11604-017-0611-5

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Language：English   Publisher：Japanese Society of Nuclear Cardiology  

Abnormal uptake of ¹⁸F-fluorodeoxyglucose (FDG) in the heart on positron emission tomography (PET) was recently included in the major criteria of diagnostic guidelines for cardiac sarcoidosis (CS). The high sensitivity but great variability in specificity in the diagnosis probably due to variable preparation methodologies of FDG-PET was reported. There are three main methods which have been reported to minimize physiological FDG uptake in the normal myocardium. A low carbohydrate diet on the day before PET with an overnight fasting more than 18-h achieves almost complete suppression of myocardial FDG uptake. Use of heparin pre-injection or high-fat diet preparation may enhance the suppressive effect. Serum FFA levels before PET imaging might be a biomarker of predicting the physiological FDG uptake in the myocardium.

DOI： 10.17996/anc.17-00037

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: Single-phase myocardial computed tomography perfusion (CTP) is useful for detecting myocardial ischemia, but determining the optimal scan time is difficult. The present study evaluated this by analyzing dynamic CTP data.
Methods and Results: We retrospectively selected 32 patients, all of whom had undergone stress dynamic CTP and magnetic resonance myocardial perfusion imaging (MR-MPI). Myocardial ischemia was assessed by MR-MPI using the 16-segment model. Whole-heart dynamic CTP data were acquired for 30 consecutive heartbeats without spatial or temporal gaps using a wide-detector CT, and redistributed into 11 series of single-phase CTP acquired from -2 s to 8 s from the time of maximal enhancement (Tmax) in the ascending aorta. Single-phase CTP images were visually assessed at the segment level, and diagnostic performance of single-phase CTP images for detecting myocardial ischemia was compared with dynamic CTP. Of 512 segments, 177 segments (35%) were diagnosed as ischemic by MR-MPI. The diagnostic accuracy of single-phase CTP acquired at 2-6 s from Tmax in the ascending aorta (median 86%, range 84-87%) was comparable to that of dynamic CTP.
Conclusions: The optimal scan time for detecting myocardial ischemia with single-phase CTP was at 2-6 s from Tmax in the ascending aorta.

DOI： 10.1253/circj.CJ-16-0834

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

To evaluate the feasibility of myocardial blood flow (MBF) by computed tomography from dynamic CT perfusion (CTP) for detecting myocardial ischemia and infarction assessed by cardiac magnetic resonance (CMR) or single-photon emission computed tomography (SPECT).
Fifty-three patients who underwent stress dynamic CTP and either SPECT (n = 25) or CMR (n = 28) were retrospectively selected. Normal and abnormal perfused myocardium (ischemia/infarction) were assessed by SPECT/CMR using 16-segment model. Sensitivity and specificity of CT-MBF (mL/g/min) for detecting the ischemic/infarction and severe infarction were assessed.
The abnormal perfused myocardium and severe infarction were seen in SPECT (n = 90 and n = 19 of 400 segments) and CMR (n = 223 and n = 36 of 448 segments). For detecting the abnormal perfused myocardium, sensitivity and specificity were 80 % (95 %CI, 71-90) and 86 % (95 %CI, 76-91) in SPECT (cut-off MBF, 1.23), and 82 % (95 %CI, 76-88) and 87 % (95 %CI, 80-92) in CMR (cut-off MBF, 1.25). For detecting severe infarction, sensitivity and specificity were 95 % (95 %CI, 52-100) and 72 % (95 %CI, 53-91) in SPECT (cut-off MBF, 0.92), and 78 % (95 %CI, 67-97) and 80 % (95 %CI, 58-86) in CMR (cut-off MBF, 0.98), respectively.
Dynamic CTP has a potential to detect abnormal perfused myocardium and severe infarction assessed by SPECT/CMR using comparable cut-off MBF.
aEuro cent CT-MBF accurately reflects the severity of myocardial perfusion abnormality.
aEuro cent CT-MBF provides good diagnostic accuracy for detecting myocardial perfusion abnormalities.
aEuro cent CT-MBF may assist in stratifying severe myocardial infarction in abnormal perfusion myocardium.

DOI： 10.1007/s00330-016-4238-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：BIOMED CENTRAL LTD  

Backround: Cardiovascular cine magnetic resonance (CMR) accelerated by compressed sensing (CS) is used to assess left ventricular (LV) function. However, it is difficult for prospective CS cine CMR to capture the complete end-diastolic phase, which can lead to underestimation of the end-diastolic volume (EDV), stroke volume (SV), and ejection fraction (EF), compared to retrospective standard cine CMR. This prospective study aimed to evaluate the diagnostic quality and accuracy of single-breath-hold full cardiac cycle CS cine CMR, acquired over two heart beats, to quantify LV volume in comparison to multi-breath-hold standard cine CMR.
Methods: Eighty-one participants underwent standard segmented breath-hold cine and CS real-time cine CMR examinations to obtain a stack of eight contiguous short-axis images with same high spatial (1.7 x 1. 7 mm(2)) and temporal resolution (41 ms). Two radiologists independently performed qualitative analysis of image quality (score, 1 [i.e., "nondiagnostic"] to 5 [i.e., "excellent"]) and quantitative analysis of the LV volume measurements.
Results: The total examination time was 113 +/- 7 s for standard cine CMR and 24 +/- 4 s for CS cine CMR (p &lt; 0.0001). The CS cine image quality was slightly lower than standard cine (4.8 +/- 0.5 for standard vs. 4.4 +/- 0.5 for CS; p &lt; 0.0001). However, all image quality scores for CS cine were above 4 (i.e., good). No significant differences existed between standard and CS cine MR for all quantitative LV measurements. The mean differences with 95 % confidence interval (CI), based on Bland-Altman analysis, were 1.3 mL (95 % CI, -14.6 - 17.2) for LV end-diastolic volume, 0.2 mL (95 % CI, -9.8 to10.3) for LV end-systolic volume, 1.1 mL (95 % CI,-10.5 to 12.7) for LV stroke volume, 1.0 g (95 % CI, -11.2 to 13.3) for LV mass, and 0.4 % (95 % CI, -4.8 - 5.6) for LV ejection fraction. The interobserver and intraobserver variability for CS cine MR ranged from -4.8 - 1.6 % and from -7.3 - 9.3 %, respectively, with slopes of the regressions ranging 0.88-1.0 and 0.86-1.03, respectively.
Conclusions: Single-breath-hold full cardiac cycle CS real-time cine CMR could evaluate LV volume with excellent accuracy. It may replace multi-breath-hold standard cine CMR.

DOI： 10.1186/s12968-016-0271-0

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: Controlling and decreasing the heart rate (HR) of patients during coronary computed tomography angiography (CCTA) is necessary to reduce radiation exposure and improve image quality. This prospective multicenter study aimed to investigate whether HR control with landiolol hydrochloride is useful for reducing radiation exposure during CCTA.
Methods and Results: We investigated 219 patients with suspected ischemic heart disease whose pretest HRs were 50-80 beats/min. We measured the HR before and after administration of landiolol hydrochloride and compared the estimated exposure inferred from the HR before administration of landiolol hydrochloride with the actual dose. After administration of landiolol hydrochloride, the mean HR (59.9 +/- 6.4 beats/min) at the time of CCTA was significantly lower than before administration (69.3 +/- 7.3 beats/min; P&lt;0.001); 80% of the patients had controlled HRs at &lt;= 65 beats/min. HR and blood pressure of all the patients recovered after the scan. The mean radiation dose in all patients was approximately 50% derived from the inferred dose before use of landiolol hydrochloride (4.5 +/- 3.2 vs. 9.0 +/- 3.7 mSv; P&lt;0.001). There were no adverse events during this study.
Conclusions: The use of landiolol hydrochloride during CCTA was safe and resulted in approximately 50% decrease in radiation exposure dose, suggesting the clinical usefulness of this drug.

DOI： 10.1253/circj.CJ-15-0962

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We evaluated the image quality and diagnostic performance of late iodine enhancement (LIE) in dual-source computed tomography (DSCT) with low kilo-voltage peak (kVp) images and a denoise filter for the detection of acute myocardial infarction (AMI) in comparison with late gadolinium enhancement (LGE) magnetic resonance imaging (MRI). The Hospital Ethics Committee approved the study protocol. Before discharge, 19 patients who received percutaneous coronary intervention after AMI underwent DSCT and 1.5 T MRI. Immediately after coronary computed tomography (CT) angiography, contrast medium was administered at a slow injection rate. LIE-CT scans were acquired via dual-energy CT and reconstructed as 100-, 140-kVp, and mixed images. An iterative three-dimensional edge-preserved smoothing filter was applied to the 100-kVp images to obtain denoised 100-kVp images. The mixed, 140-kVp, 100-kVp, and denoised 100-kVp images were assessed using contrast-to-noise ratio (CNR), and their diagnostic performance in comparison with MRI and infarcted volumes were evaluated. Three hundred four segments of 19 patients were evaluated. Fifty-three segments showed LGE in MRI. The median CNR of the mixed, 140-, 100-kVp and denoised 100-kVp images was 3.49, 1.21, 3.57, and 6.08, respectively. The median CNR was significantly higher in the denoised 100-kVp images than in the other three images (P &lt; 0.05). The denoised 100-kVp images showed the highest diagnostic accuracy and sensitivity. The percentage of myocardium in the four CT image types was significantly correlated with the respective MRI findings. The use of a denoise filter with a low-kVp image can improve CNR, sensitivity, and accuracy in LIE-CT.

DOI： 10.1007/s10554-015-0716-9

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

Purpose: We evaluated whether a quantitative circumferential strain (CS) analysis using adenosine triphosphate (ATP)-stress/rest 3-T tagged magnetic resonance (MR) imaging can depict myocardial ischemia as contractile dysfunction during stress in patients with suspected coronary artery disease (CAD). We evaluated whether it can differentiate between non-ischemia, myocardial ischemia, and infarction. We assessed its diagnostic performance in comparison with ATP-stress myocardial perfusion MR and late gadolinium enhancement (LGE)-MR imaging.
Methods: In 38 patients suspected of having CAD, myocardial segments were categorized as non-ischemic (n = 485), ischemic (n = 74), or infarcted (n = 49) from the results of perfusion MR and LGE-MR. The peak negative CS value, peak circumferential systolic strain rate (CSR), and time-to-peak CS were measured in 16 segments.
Results: A cutoff value of -12.0% for CS at rest allowed differentiation between infarcted and other segments with a sensitivity of 79%, specificity of 76%, accuracy of 76%, and an area under the curve (AUC) of 0.81. Additionally, a cutoff value of 477.3 ms for time-to-peak CS at rest allowed differentiation between infarcted and other segments with a sensitivity of 61%, specificity of 91%, accuracy of 88%, and an AUC of 0.75. The differences in CS values between ATP-stress and rest conditions ( A CS) in non-ischemic segments (median [first quartile, third quartile] -1.7 [-3.2, -0.1] %) were smaller than in segments with ischemia (+1.1 [+0.3, +2.3] %, p &lt; 0.001). A cutoff value of +0.3% for the Delta CS value could differentiate segments with ischemia from non-ischemic segments with a sensitivity of 75%, a specificity of 82%, an accuracy of 82%, and an AUC of 0.86.
Conclusions: Circumferential strain analysis using tagged MR can quantitatively assess contractile dysfunction in ischemic and infarcted myocardium. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.ejrad.2015.04.025

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The purpose of this study was to characterize hepatic parenchymal enhancement for normal and diseased liver in dynamic computed tomography (CT) with the dose of contrast medium calculated on the basis of body surface area (BSA).
The records of 328 consecutive patients who underwent triple-phase contrast-enhanced CT were retrospectively reviewed. The patients were divided into four groups: normal liver (n = 125), chronic hepatitis (CH) (n = 92), Child-Pugh grade A liver cirrhosis (LC-A) (n = 78), and Child-Pugh grade B liver cirrhosis (LC-B) (n = 33). All patients received 22 g I m(-2) as contrast material, calculated on the basis of BSA. CT values were measured in the region of interest during the pre-contrast, arterial, and portal phases, and the change in the CT value (Delta HU, where HU is Hounsfield units) compared with pre-contrast images was calculated.
Mean Delta HU for the hepatic parenchyma for the normal liver, CH, LC-A, and LC-B groups during the portal phase was 55.5 +/- A 11.8 HU, 55.2 +/- A 12.5 HU, 50.0 +/- A 13.0 HU, and 43.0 +/- A 12.7 HU, respectively; generalized estimating equation analysis showed the differences were significant (p &lt; 0.01).
Hepatic parenchymal enhancement during the portal phase decreased as the severity of chronic liver damage increased.

DOI： 10.1007/s11604-015-0398-1

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

Objectives The purpose of this study was to estimate the myocardial area at risk (MAAR) using coronary computed tomography angiography (CTA) and Voronoi algorithm-based myocardial segmentation in comparison with single-photon emission computed tomography (SPECT).
Methods Thirty-four patients with coronary artery disease underwent 128-slice coronary CTA, stress/rest thallium-201 SPECT, and coronary angiography (CAG). CTA-based MAAR was defined as the sum of all CAG stenosis (&gt;50 %) related territories (the ratio of the left ventricular volume). Using automated quantification software (17-segment model, 5-point scale), SPECT-based MAAR was defined as the number of segments with a score above zero as compared to the total 17 segments by summed stress score (SSS), difference (SDS) score map, and comprehensive SPECT interpretation with either SSS or SDS best correlating CAG findings (SSS/SDS).
Results were compared using Pearson's correlation coefficient. Results Forty-nine stenoses were observed in 102 major coronary territories. Mean value of CTA-based MAAR was 28.3 +/- 14.0 %. SSS-based, SDS-based, and SSS/SDS-based MAAR was 30.1 +/- 6.1 %, 20.1 +/- 15.8 %, and 26.8 +/- 15.7 %, respectively. CTA-based MAAR was significantly related to SPECT-based MAAR (r=0.531 for SSS; r=0.494 for SDS; r=0.814 for SSS/SDS; P&lt;0.05 in each).
Conclusions CTA-based Voronoi algorithm myocardial segmentation reliably quantifies SPECT-based MAAR.

DOI： 10.1007/s00330-014-3388-2

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER IRELAND LTD  

Background: Late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) is a useful technique for detecting myocardial fibrosis. LGE images are typically acquired using the inversion recovery (IR) method. Recently, phase-sensitive inversion recovery (PSIR) technology has been developed. The purpose of this study was to evaluate free-breathing 3D PSIR sequencing in comparison with breath-held 3D IR sequencing for the detection of myocardial fibrosis.
Methods: One hundred twenty-three patients with suspected ischemic cardiac disease (n = 27) or non-ischemic cardiomyopathy (hypertrophic cardiomyopathy, n= 29; dilated cardiomyopathy, n= 22; sarcoidosis, n= 21; arrhythmia, n= 9; myocarditis, n=4; amyloidosis, n= 3; and others, n= 8) were evaluated by LGE-MRI, which was performed first with the IR sequence and then with the PSIR sequence, using a 3 T MRI scanner. Image quality was scored by two independent readers using a four-point scale. The 3D LGE volume was analyzed quantitatively and compared between both sequencing methods.
Results: There was no significant difference in overall image quality (p = 0.19). LGE was detected in 73 patients, who were evaluated visually. Ultimately, 58 patients with acceptable image quality were enrolled in further quantitative analyses (volume assessment). Although quantification of LGE volume revealed a strong correlation between both methods, larger LGE volumes were detected with PSIR compared to IR in patients suspected of non-ischemic cardiomyopathy (39.5 +/- 25.9 cm(3) for PSIR and 32.8 +/- 23.9 cm(3) for IR, p &lt;0.001). The LGE volume did not differ significantly in patients suspected of ischemic cardiac disease (17.9 +/- 12.7 cm(3) for PSIR and 17.5 +/- 11.1 cm(3) for IR, p = 0.34).
Conclusions: 3D PSIR is suitable for detection of LGE and may be an option in cases with IR images of unacceptable quality but overestimates LGE volume in non-ischemic cardiomyopathy. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

DOI： 10.1016/j.ejrad.2014.09.014

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: Myocardial perfusion SPECT (MPS) traditionally requires the patient to be in the supine position, but diaphragmatic attenuation of the inferior wall reduces test specificity. The aim of this study was to assess the feasibility of combined MPS in the supine and prone positions using a novel cadmium zinc telluride (CZT) camera.
Methods and Results: A total of 276 consecutive patients with suspected/known coronary artery disease (CAD) who underwent single-day Tc-99m-tetrofosmin or Tc-99m-sestamibi stress/rest CZT SPECT, were enrolled in the study. Seventy-six underwent coronary angiography. Five-minute scan in the supine (S) position and thereafter in the prone (P) position produced images that were visually interpreted to obtain summed stress (SSS) and rest (SRS) scores. A combined stress score (C-SSS) was calculated by grouping anterior perfusion defects observed during supine imaging with inferior half segments observed during prone imaging. The SSS for the supine, prone, and combined protocols were 9 +/- 8, 7 +/- 8, and 7 +/- 8, respectively (P&lt;0.0001). The SRS were 5 +/- 8, 4 +/- 7, and 6 +/- 7, respectively (P=0.005). The area under the ROC curve for the S-SSS, P-SSS, and C-SSS scores was 0.815 (95% CI: 0.713-0.917), 0.813 (0.711-0.914), and 0.872 (0.783-0.961), respectively. Corresponding sensitivities and specificities for detecting CAD were 87% and 50%, 80% and 77%, and 85% and 82%, respectively. C-SSS had significantly better specificity and accuracy than S-SSS (P&lt;0.05).
Conclusions: Combined imaging with a CZT camera is suitable for routine clinical MPS and provides greater diagnostic accuracy than supine imaging alone.

DOI： 10.1253/circj.CJ-13-1316

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER INTERNATIONAL PUBLISHING AG  

Purpose: The purpose of this study was to investigate the utility incremental diagnostic value of combined assessment with coronary CT angiography (CCTA) and myocardial CT perfusion imaging (CTP) using dual-energy technology with an Adenosine Triphosphate (ATP) load technique.
Materials and methods: Twenty-one patients underwent ATP-provocation dual-energy CT and CAG. We compared the diagnostic accuracy with CAG, for ischemic region due coronary stenosis by CCTA alone and CCTA combined with CTP (Combined CCTA/CTP).
Results: All of 21 patients CTP images could be evaluated, however 8 CCTA images could not be evaluated by calcification and motion artifact, so assessability was 61.9% (13/21) for CCTA alone, and 100% for Combined CCTA/CTP. With CAG results as a comparison, the sensitivity, specificity, positive predictive value, and negative predictive value were, respectively, 83.3% (20/24), 74.4% (29/39), 66.7% (20/30), and 87.8% (29/33) for CCTA alone, and 66.7% (16/24), 92.3% (36/39), 84.2% (16/19), and 81.8% (36/44) for combined CCTA/CTP. The diagnostic accuracy of the two methods were 77.8% (49/63) and 82.5% (52/63).
Conclusion: Dual-energy CT may be a useful modality for perfusion assessment and correlated well with the severity of stenosis on CAG. This technique may even be of use in cases of severe calcification in the coronary artery wall.

DOI： 10.1186/2193-1801-3-75

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: The purpose of this study was to evaluate a personalized protocol with diluted contrast material (CM) for coronary computed tomography angiography (CTA).
Methods and Results: One hundred patients with suspected coronary artery disease underwent retrospective electrocardiogram-gated coronary CTA on a 256-slice multidetector-row CT scanner. In the diluted CM protocol (n=50), the optimal scan timing and CM dilution rate were determined by the timing bolus scan, with 20% CM dilution (5 ml/s during 10s) being considered suitable to achieve the target arterial attenuation of 350 Hounsfield units (HU). In the body weight (BW)-adjusted protocol (n=50, 222 mg iodine/kg), only the optimal scan timing was determined by the timing bolus scan. The injection rate and volume in the timing bolus scan and real scan were identical between the 2 protocols. We compared the means and variations in coronary attenuation between the 2 protocols. Coronary attenuation (mean +/- SD) in the diluted CM and BW-adjusted protocols was 346.1 +/- 23.9 HU and 298.8 +/- 45.2 HU, respectively. The diluted CM protocol provided significantly higher coronary attenuation and lower variance than did the BW-adjusted protocol (P&lt;0.05, in each).
Conclusions: The diluted CM protocol facilitates more uniform attenuation on coronary CIA in comparison with the BW-adjusted protocol.

DOI： 10.1253/circj.CJ-13-1101

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Language：English   Publishing type：Research paper (scientific journal)  

Background: The aim of this study was to investigate the correlation of the qualitative transmural extent of hypoperfusion areas (HPA) using stress dynamic whole-heart computed tomography perfusion (CTP) imaging by 256-slice CT with CTP-derived myocardial blood flow (MBF) for the estimation of the severity of coronary artery stenosis. Methods and Results: Eleven patients underwent adenosine triphosphate (0.16 mg/kg/min, 5 min) stress dynamic CTP by 256-slice CT (coverage: 8 cm, 0.27 s/rotation), and 9 of the 11 patients underwent coronary angiography (CAG). Stress dynamic CTP (whole-heart datasets over 30 consecutive heart beats in systole without spatial and temporal gaps) was acquired with prospective ECG gating (effective radiation dose: 10.4 mSv). The extent of HPAs was visually graded using a 3-point score (normal, subendocardial, transmural). MBF (ml/100g/min) was measured by deconvolution. Differences in MBF (mean ± standard error) according to HPA and CAG results were evaluated. In 27 regions (3 major coronary territories in 9 patients), 11 coronary stenoses (&gt
50% reduction in diameter) were observed. In 353 myocardial segments, HPA was significantly related to MBF (P &lt
0.05
normal 295 ± 94
subendocardial 186 ± 67
and transmural 80 ± 53). Coronary territory analysis revealed a significant relationship between coronary stenosis severity and MBF (P &lt
0.05
non-significant stenosis [&lt
50%], 284 ± 97
moderate stenosis [50-70%], 184 ± 74
and severe stenosis [&gt
70%], 119 ± 69). Conclusion: The qualitative transmural extent of HPA using stress whole-heart dynamic CTP imaging by 256-slice CT exhibits a good correlation with quantitative CTP-derived MBF and may aid in assessing the hemodynamic significance of coronary artery disease. © 2013 Kurata et al.

DOI： 10.1371/journal.pone.0083950

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background: Adenosine triphosphate (ATP) induces relative hypoperfusion in significantly stenotic coronary arteries, but its effect on myocardial strain has not been used clinically for the detection of ischemia. The purpose of this study was to quantify ATP-stress-induced contractile impairment as altered myocardial strain in coronary artery disease (CAD) using tagged magnetic resonance (MR) and to evaluate its diagnostic capability in comparison with ATP-stress myocardial perfusion-MR.
Methods and Results: Tagged MR and perfusion-MR under ATP-stress and rest conditions and late gadolinium enhancement (LGE) MR imaging were performed in 22 patients with suspected CAD. The peak absolute value of the circumferential strain (C-strain) was measured in 12 segments. Myocardial segments were categorized as non-ischemic (n=201), ischemic (n=42), or infarcted (n=21) according to the perfusion-MR and LGE MR imaging results. The absolute C-strain was significantly greater under ATP-stress (19+/-13%) (mean +/-SD) than under at-rest (15+/-11%, P&lt;0.001) conditions in non-ischemic segments. Conversely, the absolute C-strain was significantly lower under ATP-stress (10+/-13%) than under at-rest (16+/-6%, P&lt;0.01) conditions in ischemic segments. Optimal cutoff values for stress C-strain (-17.5%) could successfully differentiate segments with ischemia or infarction from non-ischemic ones with a sensitivity of 86%, a specificity of 65%, and an area under the curve of 0.79.
Conclusions: C-strain analysis using tagged MR could detect ATP-stress-induced contractile impairment in ischemic myocardium. (Circ J 2013; 77: 1235-1241)

DOI： 10.1253/circj.CJ-12-1106

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The mechanisms responsible for thromboembolic events in children with congenital heart disease have not yet been fully elucidated. Furthermore, establishment of long-term anticoagulation therapy in Fontan patients remains controversial. Here, we report the case of a 9-year-old boy who presented with hemiparesis due to a thromboembolic stroke
the boy had previously undergone staged pulmonary artery banding and Fontan procedure. Cardiac multidetector-row computed tomography (MDCT) clearly showed the supravalvular thrombus at the roofed (blind) pulmonary valve and circulatory stasis, which could be considered a possible source of the thrombus. Follow-up CT examination showed that the thrombus disappeared, but the circulatory stasis remained. Therefore, because the risk of thrombus formation was not eliminated, anticoagulation therapy was continued for the patient. Our case indicates the possible application of cardiac MDCT for providing insight into the hemodynamic mechanisms responsible for the thromboembolic events in children with congenital heart disease. © 2011 Japanese College of Cardiology.

DOI： 10.1016/j.jccase.2011.09.004

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：English   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

DOI： 10.1161/CIRCULATIONAHA.110.000315

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

We attempted to assess coronary artery flow using adenosine-stress and dual-energy mode with dual-source CT (DE-CT). Data of 18 patients with suspected coronary arteries disease who had undergone cardiac DE-CT were retrospectively analyzed. The patients were divided into two groups: 10 patients who performed adenosine stress CT, and 8 patients who performed rest CT as controls. We reconstructed an iodine map and composite images at 120 kV (120 kV images) using raw data with scan parameters of 100 and 140 kV. We measured mean attenuation in the coronary artery proximal to the distal portion on both the iodine map and 120 kV images. Coronary enhancement ratio (CER) was calculated by dividing mean attenuation in the coronary artery by attenuation in the aortic root, and was used as an estimate of coronary enhancement. Coronary stenosis was identified as a reduction in diameter of &gt; 50% on CT angiogram, and myocardial ischemia was diagnosed by adenosine-stress myocardial perfusion scintigraphy. The iodine map showed that CER was significantly lower for ischemic territories (0.76 +/- A 0.06) or stenosed coronary arteries (0.77 +/- A 0.06) than for non-ischemic territories (0.95 +/- A 0.21, P = 0.02) or non-stenosed coronary arteries (1.07 +/- A 0.33, P &lt; 0.001). The 120 kV images showed no difference in CER between these two groups. Use of CER on the iodine map separated ischemic territories from non-ischemic territories with a sensitivity of 86% and a specificity of 75%. Our quantification is the first non-invasive analytical technique for assessment of coronary artery flow using cardiac CT. CER on the iodine map is a candidate method for demonstration of alteration in coronary artery flow under adenosine stress, which is related to the physiological significance of coronary artery disease.

DOI： 10.1007/s10554-010-9676-2

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Language：English   Publishing type：Research paper (scientific journal)  

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：Japanese   Publisher：Japan Heart Foundation  

DOI： 10.11281/shinzo.43.308

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Other Link： http://search.jamas.or.jp/link/ui/2011147830

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MOSBY-ELSEVIER  

Background Multidetector-row computed tomography (MDCT) applications have expanded to evaluation of myocardial blood flow (MBF) and viability. We quantified regional MBF pre- and post-coronary artery bypass grafting (CABG) using adenosine stress and cardiac 64-MDCT, and investigated whether the results predict MBF and left ventricular (LV) function recovery after CABG.
Methods We studied 321 regions in 19 CABG patients who underwent adenosine stress 64-row MDCT perfusion imaging and cine magnetic resonance imaging pre- and post-CABG. Myocardial blood flow was estimated from linear regression equation slopes using Patlak plot analyses and compared with LV function by measuring wall thickening (%WT) using cine magnetic resonance imaging.
Results Overall mean MBFs were 1.39 +/- 0.49 and 1.95 +/- 0.49 mL/(g min) pre- and post-CABG (P &lt; .0001). Myocardial blood flow in revascularized areas increased significantly (pre-CABG 1.18 +/- 0.45, post-CABG 1.99 +/- 0.66 mL/[g min], P &lt; .001), whereas nonischemic areas showed no difference (1.79 +/- 0.70 and 1.97 +/- 0.46 mL/[g min], P = .14). Revascularized areas with preoperative MBF &gt;= 0.9 mL/(g min) showed significantly greater MBF improvement than those with preoperative MBF &lt; 0.9 mL/(g min) (P = .04). In patients with preoperative LV dysfunction (ejection fraction &lt; 40%), %WT in revascularized areas with pre-CABG MBF &gt;= 0.9 mL/(g min) improved significantly after CABG (pre-% WT 40.9 +/- 22.9, post-% WT 52.8 +/- 20.6, P = .03) versus those with pre-CABG MBF &lt; 0.9 mL/(g min) (pre-% WT 53.2 +/- 35.5, post-% WT 42.5 +/- 17.0, P = .40).
Conclusions Our results demonstrated more significantly increased MBF post-CABG than pre- CABG, particularly in revascularized areas. Regional MBF before CABG may predict MBF and LV function recovery, in the short term, after CABG. (Am Heart J 2010;160:528-34.)

DOI： 10.1016/j.ahj.2010.06.026

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Language：Japanese   Publisher：バイエル薬品(株)  

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Language：Japanese   Publisher：バイエル薬品(株)  

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Language：Japanese   Publisher：(一社)日本心臓病学会  

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：English   Publishing type：Research paper (scientific journal)  

Objective: To determine LV function at different distances from myocardial infarction (MI) by using 3-T tagged MRI and late gadolinium enhancement (LGE). Methods: Cardiac MR images were acquired from 21 patients with previous MI. The harmonic phase (HARP) method was used to calculate radial and circumferential strain (RS, CS). The two strains were synchronised by subtracting the CS from the RS at the same time, and this was defined as the efficient strain (ES). Peak strain (P-RS, P-CS, P-ES) and time to peak strain (T-RS, T-CS, T-ES) were used as estimates of contractile function. Based on the presence of LGE, myocardium was classified into infarct, border zone, adjacent and remote areas. Results: P-RS and P-ES were significantly greater for remote than for adjacent and infarct areas. P-CS values were significantly greater for remote and border zone than for infarct areas. T-RS and T-ES were significantly shorter for remote and border zone than for infarct areas. T-CS was significantly shorter for border zone than for infarct areas. Conclusion: Contractile dysfunction demonstrated by peak strain was correlated with location at different distances from the infarct. In the border zone, contractile deformation was characterised as earlier T-RS, T-CS and T-ES and greater P-CS than in the infarct area. © 2009 European Society of Radiology.

DOI： 10.1007/s00330-009-1657-2

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Language：Japanese   Publisher：バイエル薬品(株)  

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Language：Japanese   Publisher：バイエル薬品(株)  

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Language：Japanese   Publisher：バイエル薬品(株)  

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Language：Japanese   Publisher：(一社)日本核医学会  

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Language：Japanese   Publisher：(一社)日本核医学会  

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Language：Japanese   Publisher：(一社)日本心臓病学会  

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Language：Japanese   Publisher：(公社)日本医学放射線学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOC  

Background The feasibility of using cardiac multidetector-row computed tomography (MDCT) technology in the quantitative assessment of myocardial blood flow (MBF) using the adenosine triphosphate (ATP) load technique was investigated in the present study.
Methods and Results The study group comprised 14 patients (11 men, 3 women, age range 52-79 years, mean age 69.2 years) who underwent cardiac cine MDCT using the ATP-load technique. MBF was estimated from the slope of the linear regression equation with Patlak plots analysis. The overall average MBF was 1.83 +/- 0.62 ml.g(-1).min(-1). Mean MBF in territories with stenosis on coronary angiography was 1.19 +/- 0.36 ml.g(-1).min(-1) and 2.06 +/- 0.54ml.g(-1).min(-1) (p&lt;0.01) in territories without stenosis. The average MBF in territories with moderate to severe ischemia on myocardial perfusion scintigraphy was 1.32 +/- 0.14 ml.g(-1).min(-1) and 1.95 +/- 0.64 ml.g(-1).min(-1) (p&lt;0.01) in territories without ischemia.
Conclusion MDCT can be used to quantify MBF using first-pass dynamic data.

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Purpose. The purpose of this study was to investigate the feasibility of retrospective electrocardiography-gated multidetector-row computed tomography (MDCT) in the assessment left ventricular (LV) wall thickness and thickening and to test its validity compared to cine magnetic resonance imaging (MRI) as a standard of reference. Materials and methods. We enrolled 19 patients who underwent both cardiac MDCT and cine MRI. End-diastolic wall thickness (EDWT) and end-systolic wall thickness (ESWT) were measured in 16 myocardial segments. Percent systolic wall thickening (%SWT) was generated from the EDWT and ESWT. Nondiagnostic myocardial segments were excluded. Correlation and agreement between MDCT and cine MRI were analyzed. Results. Segmental assessability values were 86.2% (262/304) and 92.1% (280/304) for MDCT and cine MRI, respectively. In assessable segments by both modalities (80.9%, 246/304), a significant correlation between MDCT and MRI was found (r = 0.89, 0.85, and 0.61, for EDWT, ESWT, and %SWT, respectively
all P &lt
0.05). Mean EDWT and ESWT values by MDCT were slightly lower than those by cine MRI (9.8 ± 3.6 vs. 10.0 ± 3.7mm and 13.8 ± 4.4 vs. 14.1 ± 4.3mm, respectively
both P &lt
0.01). Bland-Altman analysis revealed acceptable limits of agreement between MDCT and Cine MRI. Conclusion. MDCT is a feasible method to assess regional LV wall thickness and systolic thickening. © 2007 Japan Radiological Society.

DOI： 10.1007/s11604-006-0113-3

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Language：Japanese   Publisher：(一社)日本循環器学会  

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Purpose. Along with the increase of detector rows on the z-axis and a faster gantry rotation speed, the spatial and temporal resolutions of the multislice computed tomography (CT) have been improved for noninvasive coronary artery imaging. We investigated the feasibility of the second specification prototype 256-detector row four-dimensional CT for assessing coronary artery and cardiac function. Materials and methods. The subjects were five patients with coronary artery disease. Contrast medium (40-60 ml) was intravenously administered at the rate of 3-4 ml/s. The patient's whole heart was scanned for 1.5 s to cover at least one cardiac cycle during breathholding without electrocardiographic gating. Parameters used were 0.5 mm slice thickness, 0.5 s/rotation, 120 Kv, and 350 mA, with a half-scan reconstruction algorithm (temporal resolution 250 ms). Twenty-six transaxial datasets were reconstructed at intervals of 50 ms. Results. The assessability of the coronary arteries in AHA segments 1, 2, 3, 5, 6, 7, 9, and 11 was visually evaluated, resulting in 29 of 32 (90.9%) segments being assessable. Functional assessment was also performed using animated movies without banding artifacts in all cases. Conclusions. The 256-detector row four-dimensional CT can assess the coronary artery and cardiac function using data during 1.5 s without banding artifacts. © Japan Radiological Society 2007.

DOI： 10.1007/s11604-006-0097-z

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Language：Japanese   Publisher：(一社)日本心臓病学会  

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：JAPANESE CIRCULATION SOCIETY  

Coronary artery fistulas (CAF) are a rare anomaly in which there is communication between a coronary artery and a cardiac chamber or another vascular structure. A giant congenital CAF to the left brachial vein was identified clearly by multidetector computed tomography (MDCT) in an 84-year-old woman who presented with orthopnea and continuous murmur. Electrocardiogram was almost normal, but chest X-ray showed marked cardiomegaly with pulmonary congestion. Transthoracic echocardiography showed that the wall motion of the left ventricle (LV) was normal, but with an abnormal cavity behind the LV. CAF was suspected and coronary angiography revealed that the CAF originated from the right coronary artery (RCA), connected to the giant vessel. However, because the drainage site was not clearly detected, MDCT was performed and it became clear that the CAF originated from the RCA. The left circumflex artery flowed into the giant vessel, and drained to the left brachial vein.

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Other Link： http://search.jamas.or.jp/link/ui/2017402750

Language：Japanese   Publisher：日本心臓核医学会  

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Language：English   Publisher：(一社)日本心血管インターベンション治療学会  

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Language：Japanese   Publisher：日本心臓核医学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER SCIENCE INC  

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J-GLOBAL

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Language：Japanese   Publisher：産業開発機構映像情報メディカル編集部  

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Other Link： http://search.jamas.or.jp/link/ui/2016022668

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Other Link： http://search.jamas.or.jp/link/ui/2015236913

Language：Japanese   Publisher：産業開発機構  

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Other Link： http://search.jamas.or.jp/link/ui/2015157647

Language：Japanese   Publisher：医学出版  

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Other Link： http://search.jamas.or.jp/link/ui/2015111488

Language：English   Publisher：ELSEVIER SCIENCE INC  

DOI： 10.1016/j.athoracsur.2014.09.065

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Language：Japanese   Publisher：(NPO)日本高血圧学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：CHURCHILL LIVINGSTONE INC MEDICAL PUBLISHERS  

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Other Link： http://search.jamas.or.jp/link/ui/2013319427

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Other Link： http://search.jamas.or.jp/link/ui/2013321550

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：Japanese   Publisher：(株)メディカルアイ  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER SCIENCE INC  

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Language：English   Publisher：OXFORD UNIV PRESS  

DOI： 10.1093/ejechocard/jer310

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DOI： 10.1253/circj.CJ-10-0389

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DOI： 10.1016/j.athoracsur.2009.09.004

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Language：Japanese   Publisher：産業開発機構  

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Other Link： http://search.jamas.or.jp/link/ui/2010285488

Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：Japanese   Publisher：文光堂  

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Other Link： http://search.jamas.or.jp/link/ui/2011171103

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Language：English   Publisher：Japanese Circulation Society  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：ELSEVIER SCIENCE INC  

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Language：Japanese   Publisher：社団法人日本循環器学会  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Other Link： http://search.jamas.or.jp/link/ui/2009019133

Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Other Link： http://search.jamas.or.jp/link/ui/2008272572

Language：Japanese   Publisher：バイエル薬品(株)  

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Language：English   Publishing type：Research paper, summary (international conference)   Publisher：LIPPINCOTT WILLIAMS & WILKINS  

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Background: Although trials of image fusion, such as positron emission computed tomography and multislice spiral computed tomography (MSCT), have already demonstrated clinical usefulness, fusion of the coronary artery image and functional image by MSCT alone has not been reported yet. Here, a new idea of data analysis is proposed in which both regional cardiac function and the responsible coronary arteries can be assessed by a fused image. Methods and Results: The study group comprised 5 patients with coronary artery disease. At the first procedure, 3 dimensional (D) volume rendering coronary artery (3D-CTA) was extracted. At the second procedure, the systolic regional wall thickening was calculated and the color 3D functional surface map of systolic wall thickening (3D-SWT) was generated. At the final procedure, 3D-SWT was superimposed on the left ventricular surface with 3D-CTA using a transparency. In all 5 patients, image fusion of the coronary tree and cardiac function was correctly generated. Image fusion can be displayed as clear 3D images, offering better orientation to help assess both the coronary artery and regional function. Conclusions: Image fusion of coronary computed tomography angiography and the functional map by MSCT is potentially a new method of assessing both the coronary artery and cardiac function.

DOI： 10.1253/circj.70.105

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Language：English   Publisher：Japanese Circulation Society  

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Language：English   Publisher：Japanese Circulation Society  

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