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We investigated the effects of the heart rate (HR) on the motion artifact in coronary computed tomography angiography (CCTA) with ultra-high-resolution-CT (U-HRCT), and we clarified the upper limit of optimal HR in CCTA with U-HRCT in a comparison with conventional-resolution-CT (CRCT) on a cardiac phantom and in patients with CCTA.A pulsating cardiac phantom equipped with coronary models was scanned at static and HR simulations of 40-90 beats/min (bpm) at 10-bpm intervals using U-HRCT and CRCT, respectively. The sharpness and lumen diameter of the coronary model were quantitatively compared between U-HRCT and CRCT stratified by HR in the phantom study. We also assessed the visual inspections of clinical images in CCTA with U-HRCT.At the HRs ≤ 60 bpm, the error of the lumen diameter of the U-HRCT tended to be smaller than that of the CRCT. However, at the HRs 60 bpm, the inverse was shown. For the image sharpness, the U-HRCT was significantly superior to the CRCT (p 0.05). In the visual assessment, the scores were negatively correlated with HRs in patients (Spearman r = - 0.71, p 0.01). A receiver-operating characteristic analysis revealed the HR of 61 bpm as the optimal cutoff of the non-diagnostic image quality, with an area under the curve of 0.87, 95% sensitivity, and 71% specificity.At HRs ≤ 60 bpm, U-HRCT was more accurate in the imaging of coronary arteries than CRCT. The upper limit of the optimal HR in CCTA with U-HRCT was approx. 60 bpm.

Recently developed and commercialized dual-layer flat panel detectors (DL-FPDs) with two indirect scintillators are capable of acquiring dual-energy X-ray images. However, in clinical practice, they are utilized to perform conventional radiography using diagnostic X-rays with a wide energy spectrum. The two layers of the DL-FPD may affect the obtained image quality, even when only using one layer for conventional image acquisition, and these effects are yet to be substantiated. Therefore, in this study, we quantitatively evaluated the image quality of a conventional chest radiography using DL-FPD and visually verified the characteristics of the chest anthropomorphic phantom images.The physical characteristics of the system were evaluated using the pre-sampled modulation transfer function (MTF), normalized noise power spectrum (NNPS), and detective quantum efficiency (DQE), for beam quality RQA 7 and RQA 9. In addition, the subjective visibility of the anthropomorphic chest phantom and simple objects images were compared with those of a conventional single-layer flat-panel detector (SL-FPD).No significant differences were found in the MTF between the SL-FPD and DL-FPD images. In addition, a higher DQE was observed at some exposure doses and in the high spatial frequency regions wherein NNPSs were lower for DL-FPD than for SL-FPD. Furthermore, no significant differences were found in the subjective visibility of the chest phantoms in each system.We concluded that the image quality of the conventional radiography acquired with DL-FPD is comparable to or better than that of the SL-FPD.

Purpose To investigate the efficacy of virtual monochromatic spectral computed tomography imaging (VMI) in the preoperative evaluation for intraductal spread of breast cancer. Materials and methods Twenty-four women who underwent spectral CT and were pathologically diagnosed with ductal carcinoma with a ≥ 2-cm noninvasive component were retrospectively enrolled in Group 1. Twenty-two women with 22 lesions pathologically diagnosed with ductal carcinoma in situ or microinvasive carcinoma were enrolled in Group 2. We compared the contrast-to-noise ratios (CNRs) of the lesions on conventional 120-kVp CT images and 40-keV VMIs in Group 1. Two board-certified radiologists measured the maximum diameters of enhancing areas on 120-kVp CT, 40-keV VMI, and MRI in Group 2 and compared with histopathological sizes. Results The quantitative assessment of Group 1 revealed that the mean ± SD of the CNRs in the 40-keV images were significantly greater than those in the 120-kVp images (5.5 ± 1.9 vs. 3.6 ± 1.5, p p = 0.017, 0.048), whereas both readers identified no significant differences between the lesion size measured on 40-keV VMI and the histopathological data. In a comparison with MRI, 40-keV VMI provided measurement within a 10-mm error range in more lesions as compared to the conventional 120-kVp CT. Conclusion VMI improves the evaluation of intraductal spread and is useful for the preoperative evaluations of breast cancer.

Background While current guidelines require lung ventilation-perfusion (V/Q) scanning as the first step to diagnose chronic pulmonary embolism in pulmonary hypertension (PH), its use may be limited by low availability and/or exposure to ionizing radiation. Purpose To compare the performance of dynamic chest radiography (DCR) and lung V/Q scanning for detection of chronic thromboembolic PH (CTEPH). Materials and Methods Patients with PH who underwent DCR and V/Q scanning in the supine position from December 2019 to July 2021 were retrospectively screened. The diagnosis of CTEPH was confirmed with right heart catheterization and invasive pulmonary angiography. Observer tests were conducted to evaluate the diagnostic accuracy of DCR and V/Q scanning. The lungs were divided into six areas (upper, middle, and lower for both) in the anteroposterior image, and the number of lung areas with thromboembolic perfusion defects was scored. Diagnostic performance was compared between DCR and V/Q scanning using the area under the receiver operating characteristic curve. Agreement between the interpretation of DCR and that of V/Q scanning was assessed using the Cohen kappa coefficient and percent agreement. Results A total of 50 patients with PH were analyzed: 29 with CTEPH (mean age, 64 years ± 15 [SD]; 19 women) and 21 without CTEPH (mean age, 61 years ± 22; 14 women). The sensitivity, specificity, and accuracy of DCR were 97%, 86%, and 92%, respectively, and those of V/Q scanning were 100%, 86%, and 94%, respectively. Areas under the receiver operating characteristic curve for DCR and V/Q scanning were 0.92 (95% CI: 0.79, 0.97) and 0.93 (95% CI: 0.78, 0.98). Agreement between the consensus interpretation of DCR and that of V/Q scanning was substantial (κ = 0.79 [95% CI: 0.61, 0.96], percent agreement = 0.9 [95% CI: 0.79, 0.95]). Conclusion Dynamic chest radiography had similar efficacy to ventilation-perfusion scanning in the detection of chronic thromboembolic pulmonary hypertension. © RSNA, 2022

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To evaluate the detectability of AKA on aortic computed tomography angiography (CTA) using ultra-high-resolution computed tomography (UHRCT). Twenty-eight patients were enrolled. They underwent aortic CTA with UHRCT (UHRCTA) and had previously undergone aortic conventional CTA (CCTA). The injection protocol of UHRCTA was the same as that of CCTA. The bolus tracking technique was used. UHRCTA images were reconstructed with adaptive iterative dose reduction (strong) and with forward-projected model-based iterative reconstruction solution. The matrix size and slice thickness on UHRCT were 1024 and 0.25 mm, respectively, and those on conventional CT were 512 and 0.5 or 0.67 mm, respectively. The UHRCTA and CCTA images were visually compared by using four scales. A score of 4 or 3 indicated that the AKA was assessable. In this instance, the contrast-to-noise ratios of each UHRCTA were measured. The exposure dose and signal-to-noise ratios were also investigated. The AKA visualization scores obtained with UHRCTA with forward-projected model-based iterative reconstruction solution were significantly higher than those with adaptive iterative dose reduction (p = 0.018) and CCTA (p = 0.0024). UHRCT can contribute to the better visualization of the AKA on aortic CTA.

Objective: / We propose a deep learning-based fully automatic right ventricle (RV) segmentation technique that targets radially reconstructed long-axis (RLA) images of the center of the RV region in routine short axis (SA) cardiovascular magnetic resonance (CMR) images. Accordingly, the purpose of this study is to compare the accuracy of deep learning-based fully automatic segmentation of RLA images with the accuracy of conventional deep learning-based segmentation in SA orientation in terms of the measurements of RV strain parameters. / Materials and Methods: / We compared the accuracies of the above-mentioned methods in RV segmentations and in measuring RV strain parameters by Dice similarity coefficients (DSCs) and correlation coefficients. Results: DSC of RV segmentation of the RLA method exhibited a higher value than those of the conventional SA methods (0.84 vs. 0.61). Correlation coefficient with respect to manual RV strain measurements in the fully automatic RLA were superior to those in SA measurements (0.5-0.7 vs. 0.1-0.2). / Results: / DSC of RV segmentation of the RLA method exhibited a higher value than those of the conventional SA methods (0.84 vs. 0.61). Correlation coefficient with respect to manual RV strain measurements in the fully automatic RLA were superior to those in SA measurements (0.5-0.7 vs. 0.1-0.2). / Discussion: / Our proposed RLA realizes accurate fully automatic extraction of the entire RV region from an available CMR cine image without any additional imaging. Our findings overcome the complexity of image analysis in CMR without the limitations of the RV visualization in echocardiography.

To determine the potential impact of on-site CT-derived fractional flow reserve (CT-FFR) on the diagnostic efficiency and effectiveness of coronary CT angiography (CCTA) in patients with obstructive coronary artery disease (CAD) on CCTA. This observational cohort study included patients with suspected CAD who had been randomized to cardiac CT in the CRESCENT I and II trials. On-site CT-FFR was blindly performed in all patients with at least one ≥ 50% stenosis on CCTA and no exclusion criteria for CT-FFR. We retrospectively assessed the effect of adding CT-FFR to the CT protocol in patients with a stenosis ≥ 50% on CCTA in terms of diagnostic effectiveness, i.e., the number of additional tests required to determine the final diagnosis, reclassification of the initial management strategy, and invasive coronary angiography (ICA) efficiency, i.e., ICA rate without ≥ 50% CAD. Fifty-three patients out of the 372 patients (14%) had at least one ≥ 50% stenosis on CCTA of whom 42/53 patients (79%) had no exclusion criteria for CT-FFR. CT-FFR showed a hemodynamically significant stenosis (≤ 0.80) in 27/53 patients (51%). The availability of CT-FFR would have reduced the number of patients requiring additional testing by 57%-points compared with CCTA alone (37/53 vs. 7/53, p

OBJECTIVE The aim of the study was to investigate the feasibility of coronary computed tomography (CT) angiography with a low kilovoltage peak scan and a refined scan timing prediction using a small contrast medium (CM) dose. METHODS In protocol A, 120-kVp scanning and a standard CM dose were used. The scan timing was fixed. In protocol B, 80 kVp and a 60% CM dose were used. The scan timing was determined according to the interval from the CM arrival to the peak time in the ascending aorta. We measured the CT number and recorded the radiation dose. RESULTS Higher CT numbers were observed in the left circumflex (proximal, P = 0.0235; middle, P = 0.0007; distal, P < 0.0001) in protocol B compared with protocol A. The radiation dose in protocol B was significantly lower than in protocol A (2.2 ± 0.9 vs 4.3 ± 1.7 mSv). CONCLUSIONS Low-contrast, low-radiation dose, high-image quality coronary CT angiography can be performed with low kilovoltage peak scanning and a refined scan timing prediction.

[Objectives] / To evaluate the usefulness of right ventricular (RV) area strain analysis via cardiac MRI (CMRI) as a tool for assessing the treatment effects of balloon pulmonary angioplasty (BPA) in inoperable chronic thromboembolic pulmonary hypertension (CTEPH), RV area strain was compared to two-dimensional (2D) strain with feature-tracking MRI (FTMRI) before and after BPA. / [Methods] / We retrospectively analyzed 21 CTEPH patients who underwent BPA. End-systolic global area strain (GAS), longitudinal strain (LS), circumferential strain (CS), and radial strain (RS) were measured before and after BPA. Changes in GAS and RV ejection fraction (RVEF) values after BPA were defined as ΔGAS and ΔRVEF. Receiver operating characteristic (ROC) analyses were performed to determine the optimal cutoff of the strain at after BPA for detection of improved patients with decreased mean pulmonary artery pressure (mPAP) less than 30 mmHg and increased RVEF more than 50 %. / [Results] / ROC analysis revealed the optimal cutoffs of strains (GAS, LS, CS, and RS) for identifying improved patients with mPAP50 % (cutoff (%) = -37.2, -29.5, -2.9, and 14.4: area under the curve, 0.81, 0.60, 0.56, and 0.56). / [Conclusions] / Area strain analysis via CMRI may be a more useful tool for assessing the treatment effects of BPA in patients with CTEPH than 2D strains with FTMRI., [Key points] / ・Area strain values can detect improvement of right ventricular (RV) pressure and function after balloon pulmonary angioplasty (BPA) equally or more accurately than two-dimensional strains. / ・Area strain analysis is a useful analytical method that reflects improvements in complex RV myocardial deformation by BPA. / ・Area strain analysis is a robust method with reproducibility equivalent to that of 2D strain analysis.

PURPOSE To evaluate the usefulness of magnetic resonance imaging (MRI) to differentiate basal cell adenomas (BCAs) from other parotid tumors. METHOD A total of 136 patients with histologically proven parotid gland tumors (13 BCAs, 66 pleomorphic adenomas [PAs], 30 Warthin tumors [WTs], and 27 parotid cancers [PCs]) who underwent a cervical MRI study between December 2011 and March 2019 were retrospectively enrolled. The MRI findings of the tumors were evaluated by two board-certified radiologists. RESULTS All 13 of the BCAs showed smooth margins, while 19 of the 27 PCs showed irregular margins (p

Background Right ventricular (RV) extracellular volumes (ECVs), as a surrogate for histologic fibrosis, have not been sufficiently investigated. Purpose To evaluate and compare RV and left ventricular (LV) ECVs obtained with dual-layer spectral detector CT (DLCT) in chronic thromboembolic pulmonary hypertension (CTEPH) and investigate the clinical importance of RV ECV. Materials and Methods Retrospective analysis was performed on data from 31 patients with CTEPH (17 were not treated with pulmonary endarterectomy [PEA] or balloon pulmonary angioplasty [BPA] and 14 were) and eight control subjects who underwent myocardial delayed enhancement (MDE) DLCT from January 2019 to June 2020. The ECVs in the RV and LV walls were calculated by using iodine density as derived from spectral data pertaining to MDE. Statistical analyses were performed with one-way repeated analysis of variance with the Tukey post hoc test or the Kruskal-Wallis test with the Steel-Dwass test and linear regression analysis. Results The PEA- and BPA-naive group showed significantly higher ECVs than the PEA- or BPA-treated group and control group in the septum (28.2% ± 2.9 vs 24.3% ± 3.6, P = .005), anterior right ventricular insertion point (RVIP) (32.9% ± 4.6 vs 25.3% ± 3.6, P < .001), posterior RVIP (35.2% ± 5.2 vs 27.3% ± 4.2, P < .001), mean RVIP (34.0% ± 4.2 vs 26.3% ± 3.4, P < .001), RV free wall (29.5% ± 3.3 vs 25.9% ± 4.1, P = .036), and mean RV wall (29.1% ± 3.0 vs 26.1% ± 3.1, P = .029). There were no significant differences between the PEA- or BPA-treated group and control subjects in these segments (septum, P = .93; anterior RVIP, P = .38; posterior RVIP, P = .52; mean RVIP, P = .36; RV free wall, P = .97; and mean RV, P = .33). There were significant correlations between ECV and mean pulmonary artery pressure (PAP) or brain natriuretic peptide (BNP) in the mean RVIP (mean PAP: R = 0.66, P < .001; BNP: R = 0.44, P = .014) and the mean RV (mean PAP: R = 0.49, P = .005; BNP: R = 0.44, P = .013). Conclusion Right ventricular and right ventricular insertion point extracellular volumes could be noninvasive surrogate markers of disease severity and reverse tissue remodeling in chronic thromboembolic pulmonary hypertension. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Sandfort and Bluemke in this issue.

PURPOSE: We investigated the impact of model-based iterative reconstruction (MBIR) on 320-detector row computed tomography angiography (CTA) in infants with complex congenital heart disease (CHD). METHODS: Seventy infants with complex CHD who underwent 320-detector row CTA (40 boys and 30 girls; age range, 0–22 months; median age, 60 days) were retrospectively evaluated. First, the images were reconstructed by filtered back projection (FBP), hybrid iterative reconstruction (HIR), or MBIR in 20 cases, and variables were compared among the three iterative reconstruction methods (IR test). Second, the variables were compared between 25 cases scanned using HIR and 25 cases scanned using MBIR, with a 20 standard deviation noise level for both. Attenuation values and contrast-to-noise ratios (CNRs) of the great vessels and heart chambers were calculated. Total dose-length products were recorded for all patients (radiation dose: RD test). RESULTS: In the IR test, the mean CNR values were 4.8±1.3 for FBP, 6.9±1.4 for HIR, and 8.2±1.7 for MBIR (p < 0.0001). The best subjective image qualities in the great vessels and heart chambers were obtained with MBIR. In RD testing, no significant differences between HIR and MBIR in image quality (CNR: HIR, 8.4±2.4; MBIR, 8.3±2.4) were observed. The effective dose was significantly lower for MBIR than for HIR (0.7±0.2 vs. 1.1±0.3 mSv; p < 0.001). CONCLUSION: The MBIR algorithm significantly improved image quality and decreased radiation exposure in 320-row CTA of infants with complex CHD, providing an alternative to FBP or HIR that is both safer and produces better results.

The purpose of this study was to investigate whether the origins and courses of the coronary arteries could be better assessed using ECG-gated dual-source computed tomography (CT) than with echocardiography in neonates with transposition of the great arteries (TGA). A total of 17 neonates within 14 days old who underwent both echocardiography and retrospective ECG-gated coronary CT angiography were retrospectively reviewed. The patients were sedated and intubated during CT examinations, and CT images were obtained with a breath-hold. CT images were reconstructed by multiple cardiac phases, and the coronary artery assessment was performed in the most static phase. Coronary anomalies were classified by Shaher’s classification and validated by surgical findings. CT correctly classified 16 of 17 cases (Shaher type 1: 7, type 2: 4, type 9: 3, type 3: 1, type 4: 2), whereas echocardiography classified only 8 of 17 cases correctly. Dual-source CT had a significantly higher diagnostic ability than echocardiography (p = 0.0078). Dual-source coronary CT angiography has a higher diagnostic ability than echocardiography in the assessment of the origins and courses of the coronary arteries in neonates with TGA.

Localized malignant pleural mesothelioma (LMPM) is an extremely rare tumor. We report the case of a 40-year-old Japanese male with an LMPM mimicking an anterior mediastinal tumor due to invasion to the anterior mediastinum, and we discuss mainly the differentiation of LMPM from an anterior mediastinal tumor. The present tumor had a long shape along the pleura, and LMPM could be one of the differential diagnoses. Keywords: Pleural mesothelioma, Localized, Pleural tumor, Radiology, LMPM

CT has advantages over MRI including rapid acquisition, and high spatial resolution for detailed anatomical information on the head and neck region. Therefore, CT is the first choice of imaging modality for the larynx, hypopharynx, sinonasal region, and temporal bone. Introduction of multi-detector CT (MDCT) scanning has allowed reduction in scan time, availability of isovoxel image, and relevant 3D image reconstruction; however, it leads to over-ranging due to helical scanning, and increased radiation dose due to 3D-volume imaging, and small detector size. In head and neck CT, reduction and optimization of radiation dose is very important, especially for prevention of the occurrence of cataract development due to radiation to lens, and prevention of the development of malignant tumour development from radiosensitive organs such as the salivary gland, thyroid gland, and retina, especially in children. The goal of dose reduction is "as low as reasonably achievable" (ALARA) level with preservation of appropriate image quality in clinical practice. Reduction of radiation dose per examination is essential; however, indication of repeat examination such as perfusion CT, dynamic contrast-enhanced CT, and follow-up study of malignant tumours should be optimized.

We explored the clinical value of low-tube voltage prospective second-generation ECG-triggered 320-row CT angiography in infants with complex CHD (37 male, 23 female, aged 0–2 years). The diagnostic accuracy of 320-row CT in complex CHD was 99.4% for intracardiac cardiovascular malformations, 99.8% for extracardiac cardiovascular malformations, and 100% for other malformations. The average subjective overall image quality score for cardiac structures was 3.7 ± 0.5 points. Second-generation 320-row CT angiography with low-tube voltage and prospective ECG-triggered volume target scanning allows accurate diagnosis of cardiovascular anomalies in infants with complex CHD.

To determine added value of permeability MRI in parotid tumor characterization to T2-weighted imaging (T2WI), semi-quantitative analysis of time-intensity curve (TIC), and intra-voxel incoherent motion diffusion-weighted imaging (IVIM-DWI). This retrospective study was approved by the institutional review board, and the informed consent was waived. Sixty-one parotid tumors in 61 patients were examined using T2WI, IVIM-DWI, and permeability MRI. TIC patterns were categorized as persistent, washout, or plateau. Signal intensity ratio of lesion-to-muscle on T2WI, apparent diffusion coefficients (ADCs), D and f values from IVIM-DWI, and Ktrans, kep, Ve, and Vp values from permeability MRI were measured. Multiple comparisons were applied to determine whether any differences among 4 histopathologic types (pleomorphic adenomas, Warthin’s tumors, other benign tumors, and malignant tumors) existed. Diagnostic accuracy was compared before and after modification diagnosis referring to permeability MRI. In a validation study, 60 parotid tumors in 60 patients were examined. ADC and D values of malignant tumors were significantly lower than those of benign tumors other than Warthin’s tumors, but higher than those of Warthin’s tumors. kep and Vp values of Warthin’s tumors were significantly higher than those of malignant tumors. Multivariate analyses showed that TIC pattern, D, and kep values were suitable parameters. McNemar’s test showed a significant increase of sensitivity (11/12, 92%) and specificity (46/49, 94%) with adding kep. The validation study yielded high sensitivity (14/16, 88%) and specificity (41/44, 93%). Permeability MRI offers added value to IVIM-MRI and semi-quantitative TIC analysis of DCE-MRI in characterization of parotid tumors • Permeability MR imaging offers added value in the characterization of parotid gland tumors in combination with semi-quantitative TIC analysis and IVIM analyses with D parameter. • The combination of TIC pattern, D, and k ep might facilitate accurate characterization of parotid gland tumor, thereby avoiding unnecessary surgery for benign tumors or delayed treatment for malignant tumors. • A combination of permeability and diffusion MR imaging can be used to guide the selection of an appropriate biopsy site.

Funding Acknowledgements None. Introduction The etiology of chest pain in hypertrophic cardiomyopathy (HCM) is diverse and includes coronary artery disease (CAD) as well as HCM-specific causes. Myocardial bridging (MB) has been associated with HCM, chest pain, and accelerated atherosclerosis. To investigate differences in the presence of MB and CAD, we compared HCM patients with age-, gender- and CAD pre-test probability (PTP)-matched outpatients presenting with chest pain. Methods We studied 84 HCM patients who underwent cardiac computed tomography and compared these with 168 matched controls (age 54 ± 11 years, 70% men, PTP 12% [5%–32%]). MB, calcium score, plaque morphology and presence and extent of CAD were assessed for each patient. Linear mixed models were used to assess differences between cases and controls. Results Differences between HCM patients and controls are described in the table. In summary, MB was more often seen in HCM patients (50% vs. 25%, p 1 segment affected (14% vs. 2%, p 0.05 for both). Conclusion MB was twice as prevalent in the HCM group. However, in a matched analysis, the prevalence and extent of CAD was equal among patients with and without HCM. These finding illustrate that despite a higher prevalence of MB, the prevalence of CAD is similar between groups, also demonstrating satisfactory performance of pre-test risk prediction in HCM patients. Assessment of CAD by CT HCM group(n = 84) Control group (n = 168) p-value Agatston score 9 [0-225] 4 [0-82] 0.22 No. of pts with score* 0.07 0-399 31 (89%) 149 (91%) >400 8 (11%) 15 (9%) Obstructive CAD 15 (18%) 32 (19%) 0.82 No. of pts with MB 42 (50%) 42 (25%) 1 segment with MB 12 (14%) 4 (2%)

A phantom for diffusion-weighted imaging is required to standardize quantitative evaluation. The objectives were to develop a phantom simulating various cell densities and to evaluate repeatability. The acrylic fine particles with three different diameters were used to simulate human cells. Four-degree cell density components were developed by adjusting the volume of 10-μm particles (5, 20, 35, and 50% volume, respectively). Two-degree components to simulate cell edema were also developed by adjusting the diameter without changing number (17% and 40% volume, respectively). Spearman’s rank correlation coefficient was used to find a significant correlation between apparent diffusion coefficient (ADC) and particle density. Coefficient of variation (CV) for ADC was calculated for each component for 6 months. A p value

It is necessary to standardize the examination procedure and diagnostic criteria of diffusion tensor imaging (DTI). Thus, the purpose of this study was to examine the reproducibility of measurements using a standardization phantom composed of different fibre materials with different fibre densities (FDs) for the evaluation of fractional anisotropy (FA) derived from DTI. Two types of fibre materials wrapped in heat-shrinkable tubes were used as fibre phantoms. We designed fibre phantoms with three different FDs of each fibre material. The standardization phantom was examined using DTI protocol six times a day, and each examination session was repeated once a month for 7 consecutive months. Fibre tracking was performed by setting regions of interest in the FA map, and FA was measured in each fibre phantom. Coefficients of variation (CVs) were used to evaluate the inter-examination reproducibility of FA values. Furthermore, Bland–Altman plots were used to evaluate the intra-operator reproducibility of FA measurements. All CVs for each fibre phantom were within 2% throughout the 7-month study of repeated DTI sessions. The high intra-operator reproducibility of the FA measurement was confirmed. High reproducibility of measurements using a standardization phantom for the evaluation of FA was achieved.

Purpose To compare the predictabilities of postoperative pulmonary function after lobectomy for primary lung cancer among counting method, effective lobar volume, and lobar collapsibility. Methods Forty-nine patients who underwent lobectomy for primary lung cancer were enrolled. All patients underwent inspiratory/expiratory CT and pulmonary function tests 2 weeks before surgery and postoperative pulmonary function tests 6–7 months after surgery. Pulmonary function losses (ΔFEV 1.0 and ΔVC) were calculated from the pulmonary function tests. Predictive postoperative pulmonary function losses (ppoΔFEV 1.0 and ppoΔVC) were calculated using counting method, effective volume, and lobar collapsibility. Correlations and agreements between ΔFEV 1.0 and ppoFEV 1.0 and those between ΔVC and ppoΔVC were tested among three methods using Spearman's correlation coefficient and Bland-Altman plots. Results ΔFEV 1.0 and ppoΔFEV 1.0insp-exp were strongly correlated (r=0.72), whereas ΔFEV 1.0 and ppoΔFEV 1.0count and ΔFEV 1.0 and Pred. ΔFEV 1.0eff.vol. were moderately correlated (r=0.50, 0.56). ΔVC and ppoΔVC eff.vol. (r=0.71) were strongly correlated, whereas ΔVC and ppoΔVC count , and ΔVC and ppoΔVC insp-exp were moderately correlated (r=0.55, 0.42). Conclusions Volumetry from inspiratory/expiratory CT data could be useful to predict postoperative pulmonary function after lobectomy for primary lung cancer.

To elucidate the utility of PROPELLER for motion artefact reduction on shoulder MRI and to examine the influence of streak artefacts on diagnosis of clinical images.15 healthy volunteers and 48 patients underwent shoulder MRI with/without PROPELLER (coronal oblique proton density-fast spin echo [PD-FSE], sagittal oblique T2-FSE). In a volunteer study, all sequences were performed in both static and exercise-loaded conditions. Two radiologists graded artefacts and delineation of various anatomical structures in the volunteer study and motion and streak artefacts in the clinical study. Mean scores were compared between sequences with/without PROPELLER. In the clinical study, mean scores of motion artefacts were compared with mean scores of streak artefacts. Wilcoxon signed-rank test was used for all comparisons.In both studies, PROPELLER significantly reduced motion artefacts (P0.05). In the volunteer study, it significantly improved delineations in sagittal oblique images in the exercise-loaded condition (P0.05). In the clinical study, streak artefacts appeared dominantly on images with PROPELLER (P0.05), but influenced diagnosis to a lesser extent than motion artefacts.PROPELLER can reduce motion artefacts in shoulder MRI. While it does cause streak artefacts, it affects diagnosis to a lesser extent.

Background Five-megapixel (MP) displays are recommended as soft copy devices for digital mammogram. An 8-MP liquid crystal display (LCD) (two 4-MP displays within one display) might offer the advantage of being able to view biplane mammography more easily than the dual planes of 5-MP LCDs. Purpose To compare detectability of Breast Imaging Reporting and Data System (BI-RADS) category 3 or higher lesions and reading time on mammography between 5- MP and 8-MP LCDs. Material and Methods The mammograms of 240 breasts of 120 patients including 60 breasts with BI-RADS category 3 or higher lesions and 180 breasts with normal or category 2 lesions were enrolled. All bilateral mammograms were displayed on bifacial 5-MP LCDs or an 8-MP LCD (two 4-MP displays within one display). Six radiologists assessed 240 breasts on each display. The observations were analyzed using receiver operating characteristic (ROC) analysis. A jack-knife method was used for statistical analysis. We employed a paired t-test to determine whether any significant differences existed in the reading time between two different displays. A P value Results The mean areas under the ROC curve obtained using 5-MP and 8-MP LCDs were 0.925 and 0.915, respectively, and there was no significant difference ( P = 0.46). There was also no significant difference in the reading time between two types of displays (57.8 min. vs. 51.5 min, P = 0.39). Conclusion The detectability of BI-RADS category 3 or higher lesions and reading time using an 8-MP LCD were comparable to those using a 5-MP LCD.

To investigate the feasibility and accuracy of measurement of the pulmonary to systemic blood flow ratio (Qp/Qs) and defect and rim sizes in secundum atrial septal defects (ASDs) using 256-slice CT, compared to the reference transoesophageal echocardiography (TEE) and right heart catheterization (RHC) measurements. Twenty-three consecutive adult patients with secundum ASDs who underwent retrospective ECG-gated coronary CT angiography (CCTA), TEE and RHC were enrolled in this study. Right ventricular (RV) and left ventricular (LV) stroke volumes (SV) were calculated by biventricular volumetry of CCTA. Qp/Qs-CT was defined as RVSV/LVSV. The sizes of the defect and rim were measured by multi-planar reconstruction CT images. Correlations between Qp/Qs-CT and Qp/Qs–RHC and between the defect diameter obtained by CT and TEE were analyzed by Pearson’s coefficient analysis. Rim sizes by CT and TEE were compared by paired t-test. Qp/Qs-CT was significantly correlated with Qp/Qs-RHC (r = 0.83, p

A 54-year-old woman diagnosed with sarcoidosis based on mediastinal lymph node biopsy underwent conventional contrast material–enhanced chest CT examination without electrocardiographic synchronization to evaluate pulmonary sarcoidosis. Past medical history included prior left total mastectomy for breast cancer (Fig 1, A). CT results demonstrated multiple hypoattenuating masses involving the septum, free walls of both ventricles, and right atrium (Fig 1, B, C). Cardiac metastases were a potential diagnosis; however, the cardiac lesions were similar in appearance to lymph nodes noted in the hilum and mediastinum. Subsequent late gadolinium enhancement MRI results showed abnormal foci of delayed enhancement in both ventricles and the right atrium, corresponding to the lesions on chest CT (Fig 1, D). Fluorine 18 fluorodeoxyglucose PET results showed abnormal uptake in these areas (maximum standardized uptake value, 12.0) (Fig 1, E). Finally, results of endomyocardial biopsy from the right ventricle revealed a granuloma with lymphocytes, demonstrating active sarcoidosis (Fig 1, F). Open in a separate window A, Contrast-enhanced CT image obtained with a delay time of 90 seconds after contrast medium injection at a slice thickness of 5 mm shows hilar and mediastinal lymphadenopathy (arrows). Note the prior left total mastectomy (arrowheads). B and C, Contrast-enhanced CT images demonstrate hypoattenuating foci in the septum, both ventricles, and right atrium (arrows). D, A four-chamber view of late enhancement MRI acquired 10 minutes after injection of gadolinium-based contrast material reveals delayed gadolinium enhancement in the septum, both ventricles, and right atrium (arrows). E, Abnormal fluorine 18 fluorodeoxyglucose (18F-FDG) uptake is observed in the septum, both ventricles, and right atrium on the 18F-FDG PET image (arrows). F, Endomyocardial biopsy specimen obtained from the right ventricle demonstrates granulomas with giant cells. (CD68 immunohistochemical staining; magnification rate, ×400.)

Purpose To assess the usefulness of amide proton transfer (APT) imaging in differentiating parotid tumors. Material and methods We retrospectively analyzed 43 histopathologically proven parotid solid tumors with diameters ≥2 cm. Twenty-one tumors were benign and 12 tumors were malignant. Two-dimensional APT imaging was performed using a saturation pulse with a duration of 2 s and a saturation power level of 2 μT. For acquiring Z-spectra, the imaging was repeated at 25 saturation frequency offsets from ω = −6 to +6 ppm with a step of 0.5 ppm as well as one scan acquired far off-resonance (−1560 ppm) for signal normalization. For the APT imaging, the asymmetry analysis at 3.5 ppm downfield from the water signal was calculated. The mean APT signal intensity (SI) was compared between the benign and malignant tumors. Results The mean APT SI was 2.23 ± 0.80 % in the benign tumors and significantly higher at 2.99 ± 0.99 % in the malignant tumors (P = 0.01). A receiver operating curve analysis revealed that the optimal APT SI threshold was 2.40 for distinguishing malignant tumors from benign tumors with an area under the curve of 0.74. The sensitivity, specificity, and accuracy were 83.3%, 61.3%, and 67.4%, respectively. Conclusion The mean APT SI of the malignant parotid tumors was significantly higher than that of the benign parotid tumors.

Purpose A 320-row CT scanner can briefly scan the entire heart. Therefore, the feasible scan timing is required. The aim of this study was to propose a refined method for feasible scan timing for coronary CT angiography (CCTA) using a time-density curve of the ascending aorta (AAo). Methods One-hundred and twenty-nine patients were prospectively enrolled. All patients were performed test-bolus method. For the initial 65 patients, the scan timing was determined as a 3.0 s delay at the peak time in the AAo, which was defined as the conventional protocol (COV-P). For the next 64 patients, a scan timing of 1.0, 3.0, or 5.0 s delay was determined according to the interval from the contrast media arrival to peak time in the AAo, which was defined as the arrival to peak protocol (AP-P). The optimal scan timing was identified by the measurement of CT number in the left atrium, left ventricle, AAo, and descending aorta. The coronary enhancement and heterogeneity were compared between the two protocols. Results The optimal scan timing was significantly higher in the AP-P than in the COV-P (85.9% vs. 61.5%, p = 0.0017). The CT number in the left circumflex artery (LCX) was significantly higher in the AP-P than the COV-P (344.5 Hounsfield units vs. 316.3 Hounsfield units, p = 0.0484). The heterogeneous index of the LCX was significantly greater for the COV-P than the AP-P (−36.8 vs. –25.8, p = 0.0028). Conclusions The AP-P can be used to determine the optimal scan timing for CCTA and contributes to stable coronary enhancement.

Background There has been no comparison of detectability of small lung cancer between general and medical LCD monitors or no comparison of detectability of small lung cancer between solid and part-solid nodules. Purpose To compare the detectabilities of T1a lung cancer on chest radiographs on three LCD monitor types: 2-megapixel (MP) for general purpose (General), 2-MP for medical purpose (Medical), and 3-MP-Medical. Material and Methods Radiographs from forty patients with T1aN0M0 primary lung cancer (27 solid nodules, 13 part-solid nodules) and 60 patients with no abnormalities on both chest X-ray and computed tomography (CT) were consecutively collected. Five readers assessed 100 cases for each monitor. The observations were analyzed using receiver operating characteristic (ROC) analysis. A jackknife method was used for statistical analysis. A P value of Results The average AUC for all T1a lung cancer nodule detection using the 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.86, 0.89, and 0.89, respectively; there were no significant differences among them. The average AUC for part-solid nodule detection using a 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.77, 0.86, and 0.89, respectively. There were significant differences between the 2-MP-General and 2-MP-Medical LCD monitors ( P = 0.043) and between the 2-MP-General and 3-MP-Medical LCD monitors ( P = 0.027). There was no significant difference between the 2-MP-Medical and 3-MP-Medical LCD monitors. The average AUC for solid nodule detection using a 2-MP-General, 2-MP-Medical, and 3-MP-Medical LCD monitors were 0.90, 0.90, and 0.88, respectively; there were no significant differences among them. The mean AUC values for all and part-solid nodules of the low-experienced readers were significantly lower than those of the high-experienced readers with the 2 M-GP color LCD monitor ( P Conclusion Detectability of part-solid nodules using a general-purpose LCD monitor was significantly lower than those using medical-purpose LCD monitors.

To investigate the performance of second-generation 320-row computed tomographic (CT) angiography (CTA) in detecting coronary arteries and identify factors influencing visibility of the coronary arteries in infants with complex congenital heart disease (CHD). Data of 60 infants (aged 0-2 years, median 2 months) with complex CHD who underwent examination using 320-row CTA with low-dose prospective electrocardiogram-triggered volume target scanning were reviewed. The coronary arteries of each infant were assessed using a 0-4-point scoring system based on the number of coronary segments with a visible course. Clinical parameters, the CT value in the ascending aorta, image noise, and the radiation dose were subjected to univariate and multivariate analyses. The mean coronary score for all examinations was 2.6 ± 1.5 points. The mean attenuation in the ascending aorta was 306.7 ± 66.2 HU and the mean standard deviation was 21.7 ± 4.4. The mean effective radiation dose was 1.27 ± 0.39 mSv. Multivariate regression analysis showed significant correlations between coronary score and body weight (p

Purpose To determine whether dual-input perfusion computed tomography (CT) can predict therapeutic response and prognosis in patients who underwent chemotherapy for non-small cell lung cancer (NSCLC). Materials and Methods The institutional review board approved this study and informed consent was obtained. Sixty-six patients with stage III or IV NSCLC (42 men, 24 women; mean age, 63.4 years) who underwent chemotherapy were enrolled. Patients were separated into three groups: those who received chemotherapy with bevacizumab (BV) (n = 20), those who received two-agent platinum-based therapy without BV (n = 25), and those who received other non-BV treatment (n = 21). Before treatment, pulmonary artery perfusion (PAP) and bronchial artery perfusion (BAP) of the tumors were calculated. Predictors of tumor reduction after two courses of chemotherapy and prognosis were identified by using univariate and multivariate analyses. Covariates included were age, sex, patient's performance status, baseline maximum diameter of the tumor, clinical stage, pretreatment PAP, and pretreatment BAP. For multivariate analyses, multiple linear regression analysis for tumor reduction rate and Cox proportional hazards model for prognosis were performed, respectively. Results Pretreatment BAP was independently correlated with tumor reduction rate after two courses of chemotherapy in the BV treatment group (P = .006). Pretreatment BAP was significantly associated with a highly cumulative risk of death (P = .006) and disease progression after chemotherapy (P = .015) in the BV treatment group. Pretreatment PAP and clinical parameters were not significant predictors of therapeutic effect or prognosis in three treatment groups. Conclusion Pretreatment BAP derived from dual-input perfusion CT seems to be a promising tool to help predict responses to chemotherapy with BV in patients with NSCLC.

Purpose. Right ventricular (RV) failure and ventricular dyssynchrony are strong determinants of prognosis in patients with adult congenital heart disease (ACHD). The aim of this study was to investigate the relationship between interventricular dyssynchrony (IVD) using cine-tagged magnetic resonance imaging (MRI) and RV dys- function in ACHD patients. Materials and Methods. Sixty-seven patients with ACHD (38 with repaired tetralogy of Fallot; 22 with atrial septal defect; seven with ventricular septal defect) underwent tagging MRI. Time curves of myocardial circumferential strains for RV and left ventricular (LV) free walls were delivered from short-axis cine-tagging images. Contraction delay between RV and LV free walls was computed by cross-correlation analysis of the two strain time curves and was defined as the IVD time (msec). Results. IVD was significantly greater for patients with RV ejection fraction (RVEF)

Purpose: To assess a recently available technique for quantification of right ventricular (RV) trabeculae that is based on fractal analysis performed by using cardiac MRI feature tracking, in patients with congenitally corrected transposition of the great arteries (cc-TGA). / Materials and Methods: A total of 19 patients (eight men, 11 women; mean age, 35 years ± 10 [standard deviation]) with consecutive cc-TGA who underwent cardiac MRI were enrolled in the study. For analysis, patients were divided into two groups: six patients (four men, two women; mean age, 34 years ± 14) with an end-systolic RV volume index higher than 72 mL/m2 (indicative of adverse RV remodeling) and 13 patients (four men, nine women; mean age, 36 years ± 9) in whom this index was lower than or equal to 72 mL/ m2 (indicative of adapted RV). The following outcomes were quantified in the midsection of the RV: fractional fractal dimension (FD) and diastolic FD, circumferential strain, and radial strain. Receiver operating characteristic (ROC) analysis was performed to determine the cutoff FD values for the detection of adverse RV remodeling. Correlations among fractional FD, diastolic FD, circumferential strain, and radial strain were calculated by using Pearson correlation coefficient (r) analysis. / Results: The following ROC values were identified for fractional and diastolic FD: cutoff, 0.09 and 1.39, respectively; area under the ROC curve, 0.95 and 0.68, respectively; sensitivity, 1.00 and 0.33, respectively; and specificity, 0.92 and 1.00, respectively. Fractional FD correlated with circumferential strain and radial strain (r = −0.70 and 0.69, respectively; P, [Key Points] / ・In patients with congenitally corrected transposition of the great arteries, the fractional fractal dimension derived by using featuretracking MRI, as compared with the conventional diastolic fractal dimension, facilitates a more accurate diagnosis of the development of right ventricular trabeculae owing to adverse remodeling. / ・ Fractal analysis performed by using feature-tracking MRI is a robust analytical method with high reproducibility. / ・ As fractal analysis performed with feature-tracking MRI does not require additional manual processing, it can be easily included with strain analysis in cardiac workflow analysis in clinical practice.

Objective To compare the detectability of simulated pulmonary nodules on chest radiographs between an irradiation side sampling indirect flat-panel detector (ISS-FPD) and computed radiography (CR). Materials and methods This study was an observer performance study. Simulated pulmonary nodules of 8 mm in diameter were superimposed on an anthropomorphic chest phantom. Chest radiographs were acquired under 2 exposure levels (4 and 3.2 mAs) with the ISS-FPD and the CR. Six thoracic radiologists evaluated all 40 images (10 patterns × 2 different exposure doses × 2 different systems) for the presence or absence of a lesion over each of 12 defined areas on a 3-megapixel monochrome liquid-crystal display. Receiver operating characteristic (ROC) curves were obtained for observation in predefined 480 areas. A jackknife method was used for statistical analysis. Differences with a P value of Results The analysis of the observer detection of simulated pulmonary nodules showed larger areas under the ROC curve (AUC) by the ISS-FPD than by the CR. There was a statistically significant difference between the two systems at 3.2 mAs ( P = 0.0330). Conclusion The ISS-FPD was superior to the CR for the detection of simulated pulmonary nodules at 3.2 mAs.

The detection of ground-glass opacities (GGOs) is an important issue in lung cancer screening with low-dose CT. The iterative reconstruction (IR) technique has the ability to improve the image quality relative to the filtered back projection (FBP) technique with low-dose CT. Our purpose was to investigate the ability to detect GGO in a chest phantom using a low-dose CT and hybrid IR, named iDose. Simulated GGOs in a chest phantom were scanned with 256-section CT at tube current second products of 20, 50, 100, and 200 mAs. Five radiologists visually assessed the detectability of GGOs in the phantom. The contrast-to-noise ratio (CNR) for GGOs was used as an estimate of image quality. Comparison of the detectability and CNR between standard images with 200 mAs-FBP and low-dose images with 20, 50, and 100-mAs FBP/iDose were performed by ANOVA with Dunnett’s and Tukey’s test. The detectability was significantly lower at 20-mAs FBP/iDose and 50-mAs FBP than that at 200-mAs FBP (p < 0.05). There was no significant difference between 50-mAs iDose and 200-mAs FBP and between 100-mAs iDose/FBP and 200-mAs FBP. The CNR was significantly higher on iDose images than that on FBP images at each mAs value. The CNR at 200-mAs FBP was the same as that at 50-mAs iDose (CNR:1.8). The hybrid IR technique and low-dose CT imaging with 50 mAs enabled noise and to maintain the detectability for GGOs in a chest phantom that is equivalent to the reference acquisitions of 200 mAs with FBP.

Purpose The aims of this study were to propose a new quantitative method for pulmonary artery (PA) flow energetics using phase-contrast magnetic resonance imaging (PC-MRI), and to investigate how balloon pulmonary angioplasty (BPA) impacts energetics in chronic thromboembolic pulmonary hypertension (CTEPH). Materials and methods PC-MRI at 3-Teslar and with a flow sensitive gradient echo was used to examine energetics prior to and following BPA for 24 CTEPH patients. Stroke volume (m; ml) and mean velocity (V; mm/s) for the main pulmonary artery (PA), right PA, and left PA were calculated from a time-flow curve derived from PC-MRI. Based on the Bernoulli principle, PA energy was identified as 1/2 mV2 (μj/kg), and energy loss was defined as the following equation “energy loss = main PA energy − (rt. PA energy + lt. PA energy)”. Results Right PA energy was significantly greater post-BPA than pre-BPA (61 ± 55 vs. 32 ± 40 μj/kg). There was no difference in main PA and left PA energies. Energy loss was significantly decreased post-BPA (18 ± 97 μj/kg) than pre-BPA (79 ± 125 μj/kg). An optimal cutoff of left PA energy of 45 μj/kg pre-BPA can be used to predict patients with mPAP ≥ 30 mmHg after BPA, with an area under the curve of 0.91, 78% sensitivity, and 92% specificity. Conclusion Analysis of PA energetics using phase-contrast MRI demonstrates that BPA improves energy loss in CTEPH. In addition, BPA responses can be predicted by PA energy status pre-treatment.

Objective:To investigate the efficacy of the radial acquisition regime (RADAR) for acquiring head and neck MR images.Methods:15 healthy volunteers underwent imaging with 4 sequences [fast spin echo T2 weighted imaging (FSE-T2WI), RADAR T2 weighted imaging (RADAR-T2WI), single-shot echo planar imaging diffusion-weighted imaging (SS-EPI-DWI) and RADAR diffusion-weighted imaging (RADAR-DWI)]. Both standard images and images during periodic mouth motion were acquired. Two radiologists scored the overall image artefacts and detectability of several anatomical structures without knowledge of sequence type. For each sequence, image distortion was quantitatively compared by the anteroposterior to right–left ratio of several anatomical structures. The mean scores of artefacts and distortion of several anatomical structures were compared using the multiple comparison test. The detectabilities were compared using the Wilcoxon signed-rank test.Results:Regardless of mouth motion, RADAR-T2WI was significantly superior ...

Quantification of myocardial oxygenation (MO) in heart failure (HF) has been less than satisfactory. This has necessitated the use of invasive techniques to measure MO directly or to determine the oxygen demand during exercise using the cardiopulmonary exercise (CPX) test. We propose a new quantification method for MO using blood-oxygen-level-dependent (BOLD) myocardial T2* magnetic resonance imaging (M-T2* MRI), and investigate its correlation with CPX results.Thirty patients with refractory HF who underwent cardiac MRI and CPX test for heart transplantation, and 24 healthy, age-matched volunteers as controls were enrolled. M-T2* imaging was performed using a 3-Tesla and multi-echo gradient-echo sequence. M-T2* was calculated by fitting the signal intensity data for the mid-left ventricular septum to a decay curve. M-T2* was measured under room-air (T2*-air) and after inhalation of oxygen for 10min at a flow rate of 10L/min (T2*-oxy). MO was defined as the difference between the two values (ΔT2*). Changes in M-T2* at the two conditions and ΔT2* between the two groups were compared. Correlation between ΔT2* and CPX results was analyzed using the Pearson coefficient.T2*-oxy was significantly greater than T2*-air in patients with HF (29.9±7.3ms vs. 26.7±6.0ms, p0.001), whereas no such difference was observed in controls (25.5±4.0ms vs. 25.4±4.4ms). ΔT2* was significantly greater for patients with HF than for controls (3.2±4.5ms vs. -0.1±1.3ms, p0.001). A significant correlation between ΔT2* and CPX results (peak VOΔT2* is increased T2*-oxy is greater in patients with HF, and is correlated with oxygen metabolism during exercise as measured by the CPX test. Hence, ΔT2* can be used as a surrogate marker of MO instead of CPX test.

To use cardiac magnetic resonance imaging (MRI) to investigate the effect of balloon pulmonary angioplasty (BPA) on interventricular dyssynchrony and its associations with ventricular interaction, which impairs LV function in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH). This prospective observational study was approved by our institutional review board. Cardiac MRI and right heart catheterization were conducted before BPA sessions and at the follow up after BPA in 20 patients with CTEPH. We measured right ventricular (RV) and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), and ejection fraction (EF) using MRI. For the LV and RV free walls, the time to peak (Tpeak) of circumferential strain was calculated as a parameter for interventricular dyssynchrony. Following BPA, the RV-EDV and -ESV were significantly decreased, and the RVEF was significantly increased. Conversely, BPA led to significantly increased LV EDV and SV without changing LVESV. The left-to-right free wall delay (L–R delay) in Tpeak strain decreased from 105 ± 44 ms to 47 ± 67 ms (p

In this study, three-dimensional phase contrast magnetic resonance imaging (3D-PC MRI), a novel technique, was validated to assess pulmonary artery (PA) flow in patients with chronic thromboembolic pulmonary hypertension (CTEPH). The MR data of PAs from 3D-PC and two-dimensional PC (2D-PC) from before and after treatment for 3 patients with CTEPH were retrospectively analyzed. Additionally, 3D- and 2D-PC MR scans of PA were performed in 5 healthy volunteers. Correlation of stroke volumes (SVs) obtained by 3D-PC and 2D-PC was analyzed using Pearson’s correlation coefficients. There was an excellent correlation in the SV of main PA, left PA and right PA between 3D-PC and 2D-PC (main PA: r = 0.91, p

To investigate myocardial viability in chronic ischemic heart disease by myocardial perfusion and regional contraction analysis using 256-slice MSCT coronary angiography (CCTA). In 30 patients with prior myocardial infarction (MI), CCTA with retrospective ECG-gating and stress-redistribution thallium-201 SPECT were performed. Using the same raw data as used for CCTA, myocardial perfusion imaging (CT-MPI) was reconstructed at four phases during the cardiac cycle. Mean myocardial attenuation and wall thickness at end-systole and end-diastole were measured in the MI areas depicted by SPECT, and they were compared between viable and non-viable segments categorized by SPECT. End-systolic thickness was significantly greater for viable than for non-viable segments (12.0 ± 3.2 vs. 9.6 ± 3.5 mm, p = 0.0017). There was no difference in end-diastolic thickness. Myocardial attenuation was significantly higher for viable than for non-viable segments in the subendocardium (62 ± 13 vs. 70 ± 11 HU, p = 0.003) and the epicardium (65 ± 13 vs. 80 ± 15 HU, p = 0.0002). The systolic wall thinning and epicardial low-attenuation areas were the indicative findings of CT-MPI for non-viable segments in the prior MI.

The aim of this study was to evaluate ventricular dysfunction using the longitudinal strain analysis in 4-chamber (4CH) cine MR imaging, and to investigate the agreement between the semi-automatic and manual measurements in the analysis. Fifty-two consecutive patients with ischemic, or non-ischemic cardiomyopathy and repaired tetralogy of Fallot who underwent cardiac MR examination incorporating cine MR imaging were retrospectively enrolled. The LV and RV longitudinal strain values were obtained by semi-automatically and manually. Receiver operating characteristic (ROC) analysis was performed to determine the optimal cutoff of the minimum longitudinal strain value for the detection of patients with cardiac dysfunction. The correlations between manual and semi-automatic measurements for LV and RV walls were analyzed by Pearson coefficient analysis. ROC analysis demonstrated the optimal cut-off of the minimum longitudinal strain values (eL_min) for diagnoses the LV and RV dysfunction at a high accuracy (LV eL_min = -7.8 %: area under the curve, 0.89; sensitivity, 83 %; specificity, 91 %, RV eL_min = -15.7 %: area under the curve, 0.82; sensitivity, 92 %; specificity, 68 %). Excellent correlations between manual and semi-automatic measurements for LV and RV free wall were observed (LV, r = 0.97, p < 0.01; RV, r = 0.79, p < 0.01). Our semi-automatic longitudinal strain analysis in 4CH cine MR imaging can evaluate LV and RV dysfunction with simply and easy measurements. The strain analysis could have extensive application in cardiac imaging for various clinical cases.

To investigate the utility of eccentricity index (EI) using cardiac cine MRI for the assessment of right ventricular (RV) hemodynamics in congenital heart disease (CHD). Fifty-five patients with CHD (32 women; mean age, 40.7 ± 20.9 years) underwent both cardiac MRI and right heart catheterization. EI was defined as the ratio of the distance between the anterior-posterior wall and the septal-lateral wall measured in the short-axis of mid-ventricular cine MRI. Correlations between EIs and RV hemodynamic parameters were analyzed. EIs were compared between patients with and without late gadolinium enhancement (LGE). A strong correlation between mean pulmonary artery pressure (PAP) and systolic EI (r = 0.81, p

To evaluate the frequency and the predictive factor of each feeding artery on intra-arterial infusion chemotherapy (IAIC) in primary tongue cancer. We retrospectively evaluated 20 patients who received IAIC for primary tongue cancer. The main and accompanying feeding arteries were identified on super-selective angiography of the branches of the external carotid artery. Tumor diameter, and extension to the contralateral side, tongue extrinsic muscles (TEMs), and lateral mesopharyngeal wall were determined based on magnetic resonance imaging or computed tomography findings. The main feeding artery was the ipsilateral lingual artery (LA) in 15 of the 20 examined tumors and the contralateral LA in the other 5. Ten cancers had only one feeding artery, and multiple feeding arteries were detected in the remaining 10. Tumors >4 cm (n = 9), those with extension to the contralateral side (n = 13), and those with extension to TEMs (n = 15) were supplied by significantly larger numbers of feeding arteries compared to tumors without these features (P = 0.01, 0.049, and 0.02, respectively). The frequency of feeding from the contralateral LA was 64 % (9/14) and 17 % (1/6) in tumors with and without extension to the contralateral side, respectively. Feeding from a facial artery (FA) was not detected in tumors ≤4 cm, while 5 of the 9 (56 %) tumors >4 cm were supplied by a FA (P = 0.01). A careful search for feeding arteries is required, especially in large tumors with extension to the contralateral side or to TEMs.