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To assess the performance of a machine learning model trained with contrast-enhanced CT-based radiomics features in distinguishing benign from malignant solid renal masses and to compare model performance with three abdominal radiologists.Patients who underwent intra-operative ultrasound during a partial nephrectomy were identified within our institutional database, and those who had pre-operative contrast-enhanced CT examinations were selected. The renal masses were segmented from the CT images and radiomics features were derived from the segmentations. The pathology of each mass was identified; masses were labeled as either benign [oncocytoma or angiomyolipoma (AML)] or malignant [clear cell, papillary, or chromophobe renal cell carcinoma (RCC)] depending on the pathology. The data were parsed into a 70/30 train/test split and a random forest machine learning model was developed to distinguish benign from malignant lesions. Three radiologists assessed the cohort of masses and labeled cases as benign or malignant.148 masses were identified from the cohort, including 50 benign lesions (23 AMLs, 27 oncocytomas) and 98 malignant lesions (23 clear cell RCC, 44 papillary RCC, and 31 chromophobe RCCs). The machine learning algorithm yielded an overall accuracy of 0.82 for distinguishing benign from malignant lesions, with an area under the receiver operating curve of 0.80. In comparison, the three radiologists had significantly lower accuracies (p = 0.02) ranging from 0.67 to 0.75.A machine learning model trained with CT-based radiomics features can provide superior accuracy for distinguishing benign from malignant solid renal masses compared to abdominal radiologists.

BACKGROUND: Obtaining ventricular volumetry and mass is key to most cardiac MRI but challenged by long multibreath-hold acquisitions. PURPOSE: To assess the image quality and performance of a highly accelerated, free-breathing, two-dimensional cine cardiac MRI sequence incorporating deep learning (DL) reconstruction compared with reference standard balanced steady-state free precession (bSSFP). MATERIALS AND METHODS: A DL algorithm was developed to reconstruct custom 12-fold accelerated bSSFP cardiac MRI cine images from coil sensitivity maps using 15 iterations of separable three-dimensional convolutions and data consistency steps. The model was trained, validated, and internally tested in 10, two, and 10 adult human volunteers, respectively, based on vendor partner-supplied fully sampled bSSFP acquisitions. For prospective external clinical validation, consecutive children and young adults undergoing cardiac MRI from September through December 2019 at a single children's hospital underwent both conventional and highly accelerated short-axis bSSFP cine acquisitions in one MRI examination. Two radiologists scored overall and volumetric three-dimensional mesh image quality of all short-axis stacks on a five-point Likert scale and manually segmented endocardial and epicardial contours. Scan times and image quality were compared using the Wilcoxon rank sum test. Measurement agreement was assessed with intraclass correlation coefficient and Bland-Altman analysis. RESULTS: Fifty participants (mean age, 16 years ± 4 [standard deviation]; range, 5–30 years; 29 men) were evaluated. The mean prescribed acquisition times of accelerated scans (non–breath-held) and bSSFP (excluding breath-hold time) were 0.9 minute ± 0.3 versus 3.0 minutes ± 1.9 (P < .001). Overall and three-dimensional mesh image quality scores were, respectively, 3.8 ± 0.6 versus 4.3 ± 0.6 (P < .001) and 4.0 ± 1.0 versus 4.4 ± 0.8 (P < .001). Raters had strong agreement between all bSSFP and DL measurements, with intraclass correlation coefficients of 0.76 to 0.97, near-zero mean differences, and narrow limits of agreement. CONCLUSION: With slightly lower image quality yet much faster speed, deep learning reconstruction may allow substantially shorter acquisition times of cardiac MRI compared with conventional balanced steady-state free precession MRI performed for ventricular volumetry. © RSNA, 2021 Online supplemental material is available for this article.

In this prospective, pilot study, we tested a kV-independent coronary artery calcium scoring CT protocol, using a novel reconstruction kernel (Sa36f). From December 2018 to November 2019, we performed an additional research scan in 61 patients undergoing clinical calcium scanning. For the standard protocol (120 kVp), images were reconstructed with a standard, medium-sharp kernel (Qr36d). For the research protocol (automated kVp selection), images were reconstructed with a novel kernel (Sa36f). Research scans were sequentially performed using a higher (cohort A, n = 31) and a lower (cohort B, n = 30) dose optimizer setting within the automatic system with customizable kV selection. Agatston scores, coronary calcium volumes, and radiation exposure of the standard and research protocol were compared. A phantom study was conducted to determine inter-scan variability. There was excellent correlation for the Agatston score between the two protocols (r = 0.99); however, the standard protocol resulted in slightly higher Agatston scores (29.4 [0-139.0] vs 17.4 [0-158.2], p = 0.028). The median calcium volumes were similar (11.5 [0-109.2] vs 11.2 [0-118.0] mm(3); p = 0.176), and the number of calcified lesions was not significantly different (p = 0.092). One patient was reclassified to another risk category. The research protocol could be performed at a lower kV and resulted in a substantially lower radiation exposure, with a median volumetric CT dose index of 4.1 vs 5.2 mGy, respectively (p < 0.001). Our results showed that a consistent coronary calcium scoring can be achieved using a kV-independent protocol that lowers radiation doses compared to the standard protocol.

General anesthesia (GA) or sedation has been used to obtain good-quality motion-free breath-hold chest CT scans in young children; however pulmonary atelectasis is a common and problematic accompaniment that can confound diagnostic utility. Dual-source multidetector CT permits ultrafast high-pitch sub-second examinations, minimizing motion artifact and potentially eliminating the need for a breath-hold. The purpose of this study was to evaluate the feasibility of free-breathing ultrafast pediatric chest CT without GA and to compare it with breath-hold and non-breath-hold CT with GA. Young (≤3 years old) pediatric outpatients scheduled for chest CT under GA were recruited into the study and scanned using one of three protocols: GA with intubation, lung recruitment and breath-hold; GA without breath-hold; and free-breathing CT without anesthesia. In all three protocols an ultrafast high-pitch CT technique was used. We evaluated CT images for overall image quality, presence of atelectasis and motion artifacts. We included 101 scans in the study. However the GA non-breath-hold technique was discontinued after 15 scans, when it became clear that atelectasis was a major issue despite diligent attempts to mitigate it. This technique was therefore not included in statistical evaluation (86 remaining patients). Overall image quality was higher (P=0.001) and motion artifacts were fewer (P

Background Limited intimal tears (LITs) of the aorta (Class 3 dissection variant) are the least common form of aortic pathology in patients presenting with acute aortic syndrome (AAS). LITs are difficult to detect on imaging and may be underappreciated. Objectives This study sought to describe the frequency, pathology, treatment, and outcome of LITs compared with other AAS, and to demonstrate that LITs can be detected pre-operatively by contemporary imaging. Methods The authors retrospectively reviewed 497 patients admitted for 513 AAS events at a single academic aortic center between 2003 and 2012. AAS were classified into classic dissection (AD), intramural hematoma, LIT, penetrating atherosclerotic ulcer, and rupturing thoracic aortic aneurysm. The prevalence, pertinent risk factors, and detailed imaging findings with surgical and pathological correlation of LITs are described. Management, early outcomes, and late mortality are reported. Results Among 497 patients with AAS, the authors identified 24 LITs (4.8% of AAS) in 16 men and 8 women (17 type A, 7 type B). Patients with LITs were older than those with AD, and type A LITs had similarly dilated ascending aortas as type A AD. Three patients presented with rupture. Eleven patients underwent urgent surgical aortic replacement, and 2 patients underwent endovascular repair. Medial degeneration was present in all surgical specimens. In-hospital mortality was 4% (1 of 24), and in total, 5 patients with LIT died subsequently at 1.5 years (interquartile range [IQR]: 0.3 to 2.5 years). Computed tomography imaging detected all but 1 LIT, best visualized on volume-rendered images. Conclusions LITs are rare acute aortic lesions within the dissection spectrum, with similar presentation, complications, and outcomes compared with AD and intramural hematoma. Awareness of this lesion allows pre-operative diagnosis using high-quality computed tomography angiography.

To evaluate the capacity of perfusion CT imaging to distinguish between complete and incomplete responders after neoadjuvant chemoradiation therapy for rectal carcinoma, with particular attention to segmentation technique. 17 patients were evaluated in this prospective IRB-approved study. For each patient, a perfusion CT acquisition was obtained prior to the initiation of chemoradiation, at 1–2 weeks after the start of chemoradiation, and at 12 weeks after the start of chemoradiation therapy. From each dataset, three perfusion parameters were measured, each in two different ways: a region of interest incorporating only “hot spots” of greatest enhancement and whole-tumor measurements. In univariate analysis, blood volume and permeability differed significantly between responders and non-responders. In logistic regression analysis evaluating predictors of the “complete response” outcome, only two predictors were retained as statistically significant: peak hot spot blood volume 1–2 weeks into therapy (OR 10.25, p = 0.0026) and hot spot permeability decline at 12 weeks after the initiation of therapy (OR 5.62, p = 0.03). The overall likelihood ratio test for this model supported the conclusion that hot spot blood volume and hot spot permeability decline were significant predictors of the complete pathologic response outcome (p

Purpose Chronic kidney disease (CKD) is prevalent in transcatheter aortic valve replacement (TAVR) candidates, leading to concerns regarding contrast medium (CM) safety. We evaluated (a) the impact of low-CM imaging on pre-TAVR measurements and (b) postcontrast acute kidney injury (PC-AKI) prevalence after dual-source computed tomography (DSCT) in TAVR candidates. Methods All TAVR candidates with CKD (SCr≥1.5 mg/dL) who underwent weight-based low-CM, low-pitch helical 3rd-generation DSCT in a one-year period were included, and matched to standard-CM, non-CKD controls (N = 50). Image quality (IQ) and pre-TAVR measurement interobserver variability were evaluated. Renal function change and PC-AKI were studied in the entire TAVR cohort, irrespective of scan mode (N = 153). Results Low-CM in CKD (N = 25) was performed with median 68 mL CM [52–87], 90 kV [80–90] and SCr 1.6 mg/dL [1.5–1.9], and standard-CM without CKD with median 116 mL CM [96–134], 100 kV [90–110] and SCr 1.0 mg/dL [0.9–1.1](P 0.85). Interobserver-agreement was lower in low-CM, causing prosthesis size disagreement in 5/25 (kappa-0.73) versus 0/25 with standard-CM (kappa-1.00), and transfemoral eligibility disagreement in 4/25 (kappa-0.68) versus 2/25 (kappa-0.84), respectively. Mean 1-month SCr-change in the low-CM TAVR cohort (N = 35) was −1 % [−12 to +7 %] and in standard-CM (N = 118) 0 % [−8 to +10 %](P > 0.3). PC-AKI occurred in none. Conclusion Low-CM third-generation-DSCT achieves good IQ in TAVR candidates with CKD, and seems safe, with no apparent renal function deterioration or prevalence of PC-AKI. However, standard-CM protocols in non-CKD patients provide higher measurement reproducibility. Low-CM protocols should therefore be reserved for patients at high risk for PC-AKI.

Computed tomography (CT) perfusion is a novel imaging method to determine tumor perfusion using a low-dose CT technique to measure iodine concentration at multiple time points. We determined if early changes in perfusion differ between primary renal tumors and metastatic tumor sites in patients with renal cell carcinoma (RCC) receiving targeted anti-angiogenic therapy. A total of 10 patients with advanced RCC underwent a CT perfusion scan at treatment baseline and at one week after initiating treatment. Perfusion measurements included blood volume (BV), blood flow (BF), and flow extraction product (FEP) in a total of 13 lesions (six primary RCC tumors, seven RCC metastases). Changes between baseline and week 1 were compared between tumor locations: primary kidney tumors vs metastases. Metastatic lesions had a greater decrease in BF (average BF difference &plusmn, standard deviation (SD): &minus, 75.0 mL/100 mL/min &plusmn, 81) compared to primary kidney masses (&minus, 25.5 mL/100 mL/min &plusmn, 35). Metastatic tumors had a wider variation of change in BF, BV and FEP measures compared to primary renal tumors. Tumor diameters showed little change after one week, but early perfusion changes are evident, especially in metastatic lesions compared to primary lesions. Future studies are needed to determine if these changes can predict which patients are benefiting from targeted therapy.

The purpose of this study was to assess in pediatric pulmonary artery (PA) reconstruction candidates the feasibility and added utility of preoperative chest computed tomography angiography (CTA) using dual-energy technique, from which perfused blood volume (PBV)/iodine maps can be generated as a surrogate of pulmonary perfusion. Pediatric PA reconstruction patients were prospectively recruited for a new dose-neutral dual-energy CTA protocol. For each case, the severity of anatomic PA obstruction was graded by two pediatric cardiovascular radiologists in consensus using a modified Qanadli index. PBV maps were qualitatively reviewed and auto-segmented using Siemens syngo.via software. Associations between Qanadli scores and PBV were assessed with Spearman correlation (r) and ROC analysis. Effective radiation doses were estimated from dose-length product and ICRP 103 k-factors, using cubic Hermite spline interpolation. 19 patients were recruited with mean (SD) age of 6.0 (5.1), 11 (57.9%) female, 11 (73.7%) anesthetized. Higher QS correlated with lower PBV, both on a whole lung (r = − 0.54, p

Purpose To compare the precision and inter-observer agreement of ventricular volume, function and mass quantification by three-dimensional time-resolved (4D) flow MRI relative to cine steady state free precession (SSFP).

Objective To evaluates a semi-automated method for Thoracic Aortic Aneurysm (TAA) measurement using ECG-gated Dual Source CT Angiogram (DSCTA). Methods This retrospective HIPAA compliant study was approved by our IRB. Transaxial maximum diameters of outer wall to outer wall were studied in fifty patients at seven anatomic locations of the thoracic aorta: annulus, sinus, sinotubular junction (STJ), mid ascending aorta (MAA) at the level of right pulmonary artery, proximal aortic arch (PROX) immediately proximal to innominate artery, distal aortic arch (DIST) immediately distal to left subclavian artery, and descending aorta (DESC) at the level of diaphragm. Measurements were performed using a manual method and semi-automated software. All readers repeated their measurements. Inter-method, intra-observer and inter-observer agreements were evaluated according to intraclass correlation coefficient (ICC) and Bland–Altman plot. The number of cases with manual contouring or center line adjustment for the semi-automated method and also the post-processing time for each method were recorded. Results The mean difference between semi-automated and manual methods was less than 1.3 mm at all seven points. Strong inter-method, inter-observer and intra-observer agreement was recorded at all levels (ICC ≥ 0.9). The maximum rate of manual adjustment of center line and contour was at the level of annulus. The average time for manual post-processing of the aorta was 19 ± 0.3 min, while it took 8.26 ± 2.1 min to do the measurements with the semi-automated tool (Vitrea version 6.0.0.1 software). The center line was edited manually at all levels, with most corrections at the level of annulus (60%), while the contour was adjusted at all levels with highest and lowest number of corrections at the levels of annulus and DESC (75% and 0.07% of the cases), respectively. Conclusion Compared to the commonly used manual method, semi-automated measurement of vessel dimensions is feasible in the thoracic aorta with the advantage of reduced post-processing time.

Rationale:Various types of viable stem cells have been reported to result in modest improvement in cardiac function after acute myocardial infarction. The mechanisms for improvement from different stem cell populations remain unknown. Objective:To determine whether irradiated (nonviable) embryonic stem cells (iESCs) improve postischemic cardiac function without adverse consequences. Methods and Results:After coronary artery ligation-induced cardiac infarction, either conditioned media or male murine or male human iESCs were injected into the penumbra of ischemic myocardial tissue of female mice or female rhesus macaque monkeys, respectively. Murine and human iESCs, despite irradiation doses that prevented proliferation and induced cell death, significantly improved cardiac function and decreased infarct size compared with untreated or media-treated controls. Fluorescent in situ hybridization of the Y chromosome revealed disappearance of iESCs within the myocardium, whereas 5-bromo-2′-deoxyuridine assays r...

Background— Medical treatment of initially uncomplicated acute Stanford type-B aortic dissection is associated with a high rate of late adverse events. Identification of individuals who potentially benefit from preventive endografting is highly desirable. Methods and Results— The association of computed tomography imaging features with late adverse events was retrospectively assessed in 83 patients with acute uncomplicated Stanford type-B aortic dissection, followed over a median of 850 (interquartile range 247–1824) days. Adverse events were defined as fatal or nonfatal aortic rupture, rapid aortic growth (>10 mm/y), aneurysm formation (≥6 cm), organ or limb ischemia, or new uncontrollable hypertension or pain. Five significant predictors were identified using multivariable Cox regression analysis: connective tissue disease (hazard ratio [HR] 2.94, 95% confidence interval [CI]: 1.29–6.72; P =0.01), circumferential extent of false lumen in angular degrees (HR 1.03 per degree, 95% CI: 1.01–1.04, P =0.003), maximum aortic diameter (HR 1.10 per mm, 95% CI: 1.02–1.18, P =0.015), false lumen outflow (HR 0.999 per mL/min, 95% CI: 0.998–1.000; P =0.055), and number of intercostal arteries (HR 0.89 per n, 95% CI: 0.80–0.98; P =0.024). A prediction model was constructed to calculate patient specific risk at 1, 2, and 5 years and to stratify patients into high-, intermediate-, and low-risk groups. The model was internally validated by bootstrapping and showed good discriminatory ability with an optimism-corrected C statistic of 70.1%. Conclusions— Computed tomography imaging-based morphological features combined into a prediction model may be able to identify patients at high risk for late adverse events after an initially uncomplicated type-B aortic dissection.

Contrast enhanced magnetic resonance imaging (CeMRI) reliably identifies myocardial fibrosis in patients with hypertrophic cardiomyopathy (HCM). However, many patients have contraindications to ceMRI. Previous studies have shown that contrast enhanced multi-detector computed tomography (ceMDCT) can visualize focal scars following myocardial infarction in experimental animals and patients. The purpose of this manuscript is to assess the ability of ceMDCT to detect focal myocardial scars in patients with HCM. Twelve HCM patients underwent ceMRI and ceMDCT. Fibrotic areas of myocardium were defined as focal or diffuse areas of fibrosis. The mean signal intensity in ceMRI and attenuation values in ceMDCT of the fibrotic regions, normal myocardium and left ventricle blood pool contrast were measured using qualitative and quantitative analysis. Focal scar mass was calculated using both techniques. Focal scars were detected in 9 patients and diffuse fibrosis was visualized in all patients by ceMRI. Differences between normalized SI of normal myocardium and focal scars, normal and diffuse areas of fibrosis, and diffuse fibrosis and focal scars were significant for both ceMRI and ceMDCT (p

To compare the precision and interobserver agreement of ventricular volume, function, and mass quantification by 3D time-resolved (4D) flow MRI relative to cine steady-state free precession (SSFP).With Institutional Research Board approval, informed consent, and HIPAA compliance, 22 consecutive patients with congenital heart disease (CHD) (10 males, 6.4 ± 4.8 years) referred for 3T ferumoxytol-enhanced cardiac MRI were prospectively recruited. Complete ventricular coverage with standard 2D short-axis cine SSFP and whole chest coverage with axial 4D flow were obtained. Two blinded radiologists independently segmented images for left ventricular (LV) and right ventricular (RV) myocardium at end systole (ES) and end diastole (ED). Statistical analysis included linear regression, analysis of variance (ANOVA), Bland-Altman (BA) analysis, and intraclass correlation (ICC).Significant positive correlations were found between 4D flow and SSFP for ventricular volumes (r = 0.808-0.972, P0.001), ejection fraction (EF) (r = 0.900-928, P0.001), and mass (r = 0.884-0.934, P0.001). BA relative limits of agreement for both ventricles were between -52% to 34% for volumes, -29% to 27% for EF, and -41% to 48% for mass, with wider limits of agreement for the RV compared to the LV. There was no significant difference between techniques with respect to mean square difference of ED-ES mass for either LV (F = 2.05, P = 0.159) or RV (F = 0.625, P = 0.434). Interobserver agreement was moderate to good with both 4D flow (ICC 0.523-0.993) and SSFP (ICC 0.619-0.982), with overlapping confidence intervals.Quantification of ventricular volume, function, and mass can be accomplished with 4D flow MRI with precision and interobserver agreement comparable to that of cine SSFP. J. Magn. Reson. Imaging 2016;44:383-392.

First-pass perfusion MRI is a promising technique for detecting ischemic heart disease. However, the diagnostic value of the method is limited by the low spatial coverage, resolution, signal-to-noise ratio (SNR), and cardiac motion-related image artifacts. In this study we investigated the feasibility of using a method that combines sliding window and CG-HYPR methods (SW-CG-HYPR) to reduce the acquisition window for each slice while maintaining the temporal resolution of one frame per heartbeat in myocardial perfusion MRI. This method allows an increased number of slices, reduced motion artifacts, and preserves the relatively high SNR and spatial resolution of the "composite images." Results from eight volunteers demonstrate the feasibility of SW-CG-HYPR for accelerated myocardial perfusion imaging with accurate signal intensity changes of left ventricle blood pool and myocardium. Using this method the acquisition time per cardiac cycle was reduced by a factor of 4 and the number of slices was increased from 3 to 8 as compared to the conventional technique. The SNR of the myocardium at peak enhancement with SW-CG-HYPR (13.83 +/- 2.60) was significantly higher (P < 0.05) than the conventional turbo-FLASH protocol (8.40 +/- 1.62). Also, the spatial resolution of the myocardial perfection images was significantly improved. SW-CG-HYPR is a promising technique for myocardial perfusion MRI.

Noncompaction of ventricular myocardium (NCVM) is a rare cardiomyopathy characterized by numerous prominent trabeculations in the ventricular wall and deep intertrabecular recesses communicating with the ventricular cavity. This article reports a 33-year-old female with a familial history of cardiovascular disease, who presented with shortness of breath and palpitations. Transesophageal echocardiography and cardiac magnetic resonance imaging (MRI) were consistent with the diagnosis of NCVM. The advantages of MRI in depicting both the morphological features and pathological characteristics of NCVM were presented.

Purpose To study the frequency and demographics of lung cancer on CT pulmonary angiography in patients with suspected pulmonary embolism referred from the Emergency Department. Materials and methods Retrospective review of the medical records and radiology reports, clinical and imaging follow-up studies and pathological reports revealed 1106 CT pulmonary angiography studies referred from our Emergency Department during the 15-month period between March 2003 and June 2004. Results Five incidental lung cancer cases were found in 1106 studies from 1081 patients (0.47%). Pulmonary embolism was found in 95 patients (8.5%). Among the five incidental cases three patients were female and two were male (62–81 years old; mean 73 years, 17–130 packs year; mean 51 packs year). Tumor size ranged from 1.8 to 4.5 cm (mean 3.3 cm). The stagings of the lung cancers were IIIB in one patient and IV in four patients. Conclusion Previously undiagnosed lung cancer was detected in 0.45% of patients among 1081 patients referred from Emergency Department, one of whom had coexistent pulmonary embolism. All five patients presented at advanced lung cancer stages of IIIB and IV.

496 Background: We need biomarkers of response to guide treatment decisions in RCC. Our pilot study uses perfusion CT to assess early changes in tumor vascularity in response to targeted therapies. We will determine if perfusion CT measurements can help predict response to therapy after 1 week of treatment in patients with metastatic RCC. Methods: Nine patients with metastatic renal cell carcinoma treated with targeted therapy have been enrolled to date. CT perfusion measures were collected: (1) prior to treatment, (2) 7-10 days after start of treatment, and (3) 12 weeks after start of treatment. At each time point, 5 measures were analyzed: (1) blood volume (BV), (2) blood flow (BF), (3) mean transit time (MTT), (4) flow extraction product (FEP), and (5) tumor size. Clinical response was determined based on RECIST criteria. Univariate and multivariate logistic regression analyses were conducted to determine the association of the CT perfusion measures and clinical response. The relationship between clinical response and individual measure at each time point, change in each measure at each time point, and the rate of change over the measure across all time points (slope) were evaluated in each patient. Results: We found that two blood volume measurements are associated with outcome. 5/9 (56%) patients had stable disease and 4/9 (44%) had progressive disease. Decrease in blood volume from time prior to treatment to 7-10 days after start of treatment was significantly associated with decreased odds of having stable disease (OR 0.63 (0.4-0.99), p=0.04). When examining the rate of change, the slope of blood volume was significantly associated with decreased odds of having stable disease (OR 0.52 (0.27-1.01), p=0.05). Univariable logistic regression for each individual CT measure, FEP prior to treatment (OR 1.07 (0.99-1.15), p=0.08) and 12 weeks after treatment (OR 1.13 (0.99-1.29), p=0.06) were not significantly associated with stable disease. Conclusions: Changes in blood volume including absolute difference as well as rate of change of blood volume were statistically significantly different between patients with stable disease versus progressive disease. Clinical trial information: NCT01926990.

Purpose: To evaluate inter method and intra observer variability of a novel semi-automated method for measurement of ascending aorta aneurysm (AAA) in ECG gated dual source CT angiogram (DSCTA). Material and Method: Under an IRB approved protocol, multiplanar reformatted images of 40 patients with AAA were measured in DSCTA images. Transaxial maximum diameter of inner wall to inner wall was measured at five anatomic locations of thoracic aorta: annulus, sinus, sinotubular junction (STJ), mid ascending aorta at the level of right pulmonary artery (MAA), and proximal aortic arch immediately proximal to innominate artery (PROX) (Figure 1). Measurements were performed by conventional manual method and the novel semi-automated segmentation software and compared. Inter method and intra observer variability were evaluated according to Intra Class Correlation (ICC). Time required for post processing of the aorta with both methods was recorded in all the cases. Results: Mean maximum diameters in semi-automated method were: annulus 31.10 mm, sinus: 41.95 mm, STJ: 38.05 mm, MAA: 41.88 mm, and PROX: 37.60 mm. Manual method showed mean maximum diameter of 30.87 mm, 42.05 mm, 36.87 mm, 41.18 mm, and 36.42 mm at annulus, sinus, STJ, MAA, and PROX, respectively. There was an excellent inter method and intra observer agreement between two methods at all five points (ICC > 0.9). The post processing time was 8’2’’±1’35” for the semi-automated method while this time was 19’± 20” for the manual method. Conclusion: The novel semi-automated tool demonstrated an excellent agreement with conventional manual method in measurement of AAA in ECG gated DSCTA with the advantage of significant reduction in the post processing time.

Late gadolinium enhancement (LGE) on cardiac magnetic resonance (CMR) imaging detects myocardial scar/fibrosis in hypertrophic cardiomyopathy (HCM) patients. LGE has been associated with nonsustained ventricular tachycardia (NSVT), and clinical risk factors for sudden cardiac death. We investigated

Summary The purpose of this study was to investigate the relationship between the extent of hyperenhancement and left ventricle maximal wall thickness (mWT) detected by LGE CMR and clinical events of nonsustained ventricular tachycardia (NSVT), implantation of cardioverter defibrillator (ICD) or diastolic heart failure in HCM patients that underwent LGE CMR. Background Late gadolinium enhancement cardiac magnetic resonance (LGE CMR) imaging has been used to detect myocardial hypertrophy and scar/fibrosis in Hypertrophic cardiomyopathy (HCM) patients. The presence of hyperenhancement has been associated with progressive ventricular dilation, ventricular arrhythmias and clinical risk factors for sudden cardiac death. Methods Under IRB approved protocol a total of 82 HCM patients underwent LGE CMR images using a 2D PSIR TurboFLASH protocol after administration of 0.2 mmol of gadopentetate dimeglumine per kilogram of body weight. The presence of LGE was assessed using automated software: percentage of scar and maximal wall thickness were calculated. Percentage of scar was compared between patients with mWT

Summary The purpose of the study is to evaluate a fully automated motion corrected first pass myocardial perfusion (FPMP) MRI with semi quantitative perfusion parameter maps in patients with suspected ischemic heart disease. Background Coronary heart disease is the leading cause of death and disability in the US. FPMP MRI is increasingly used to assess ischemic heart disease; however respiratory motion is one of the major problems for myocardial blood flow quantification. An algorithm for motion correction, surface coil correction, temporal denoising and robust pixel-wise parameter map generation model was previously desribed [Xue H et al MICCAI 2009).This work evaluates automated workflow in a clinical setting to diagnose ischemic heart disease comparing free breathing and motion correcteted images and corresponding pixel-wise parameter map. Methods Stress and rest FPMP images were acquired using a 1.5T scanner (MAGNETOM Avanto, Siemens Healthcare) in 39 patients with suspected ischemic heart disease. Short axis slices were acquired during infusion of 0.075 mMol/kg of Gadolinium (Magnevist, Bayer HealthCare Pharmaceuticals, USA) and adenosine (Adenoscan, AstellasPharma, USA) infusion (0.14 mg/kg/min; duration: 4 min) was administrated to induce stress. Free breathing, motion-corrected images and corresponding perfusion maps were assessed by 2 radiologists independently using the AHA 16 model and evaluated using a four point Likert scale (poor to excellent) to evaluate image quality and confidence level in presence or absence of hypo-perfusion regions. Upslope index of both free breathing and motion corrected images during stress and rest were manually calculated in nonischemic and ischemic areas and compared to the corresponding pixel-wise parameter map generated based on motion corrected images. FPMP MRI results were subsequently compared to coronary angiogram, stress echocardiography, or SPECT.

Summary We measured extracellular volume fraction (Ve) from pre- and post-contrast T1 maps of the left ventricle in 13 patients with systemic sclerosis (SSc) and 13 agematched controls. SSc patients and controls were similar with regard to LV and RV mass, volumes, and function. However, Ve was significantly higher in SSc patients than in controls, even when patients with visible late gadolinium enhancement were excluded. Ve correlated with SSc severity as measured by the modified Rodnan Skin Score. Ve may be valuable for detection of myocardial involvement in SSc, even when conventional CMR appears normal. Background Primary cardiac involvement is common in systemic sclerosis (SSc) and responsible for 25% of deaths. Myocardial extracellular volume fraction (Ve), derived from cardiac magnetic resonance (CMR) T1 mapping of the myocardium, has been shown to quantify diffuse myocardial fibrosis (DMF) - but its utility in SSc has not been studied. We hypothesized that subjects with SSc have a higher Ve compared to controls and that patients with worse SSc severity have higher Ve. Methods CMR was performed in 13 SSc patients (5 diffuse and 8 limited cutaneous) and 13 age-matched controls. Cine, pre- and post- contrast T1 mapping, and late gadolinium enhanced (LGE) imaging was performed. LV mass index (LVMi), LV end-diastolic volume index (LVEDVi), LV ejection fraction (EF), RV mass index (RVMi), RV

Background To quantify myocardial T2 value in patients with myocarditis and correlate the distribution of abnormal T2 values with the extent of macroscopic late gadolinium enhancement (LGE). Methods 25 patients with myocarditis were retrospectively evaluated for the utility of T2 mapping in diagnosing myocarditis. Patients with elevated troponins, negative coronary angiogram, and atypical LGE were diagnosed as acute myocarditis. Patients with normal troponins and macroscopic LGE at the time of cardiac MRI were diagnosed as remote myocarditis. As per our institutional protocol, T2 mapping sequences were performed in all cases with suspected myocarditis in addition to standard LGE images on 1.5 T scanner (Magnetom Aera and Avanto, Siemens medical solutions). T2 mapping was performed on three short axis images (base, mid chamber, and apex), yielding 16 myocardial segments for analysis (AHA segments). Single 4 chamber view image was obtained in addition. Minimum, peak and mean segmental T2 values were calculated by the first reader. Average segmental T2 values were documented along with documentation of the number of segments with elevated T2 values. The presence or absence of LGE was documented by a second reader blinded to the T2 results. Average segmental T2 values were then correlated with troponin levels at the time of the MRI examination. Results In patients with acute myocarditis, mean T2 values were elevated in segments showing LGE (average T2 value of 70 msec). The T2 values were also elevated in myocardial segments with no macroscopic LGE (avg 60 msec). On an average, there were 6 additional segments that showed elevated T2 values and no macroscopic LGE. In patients with remote myocarditis, the T2 values were normal in areas of LGE.

Purpose: First-pass perfusion magnetic resonance imaging (MRI) is a promising technique for detecting ischemic heart disease. However, the diagnostic value of the method is limited by the low spatial coverage, resolution, signal-to-noise ratio (SNR), and cardiac motion-related image artifacts. A combination of sliding window and conjugate-gradient HighlY constrained back-PRojection reconstruction (SW-CG-HYPR) method has been proposed in healthy volunteer studies to reduce the acquisition window for each slice while maintaining the temporal resolution of 1 frame per heartbeat in myocardial perfusion MRI. This method allows for improved spatial coverage, resolution, and SNR. Methods: In this study, we use a controlled animal model to test whether the myocardial territory supplied by a stenotic coronary artery can be detected accurately by SW-CG-HYPR perfusion method under pharmacological stress. Results: Results from 6 mongrel dogs (15-25 kg) studies demonstrate the feasibility of SW-CG-HYPR to detect regional perfusion defects. Using this method, the acquisition time per cardiac cycle was reduced by a factor of 4, and the spatial coverage was increased from 2 to 3 slices to 6 slices as compared with the conventional techniques including both turbo-Fast Low Angle Short (FLASH) and echoplanar imaging (EPI). The SNR of the healthy myocardium at peak enhancement with SW-CG-HYPR (12.68 ± 2.46) is significantly higher (P < 0.01) than the turbo-FLASH (8.65 ± 1.93) and EPI (5.48 ± 1.24). The spatial resolution of SW-CG-HYPR images is 1.2 x 1.2 x 8.0 mm 3 , which is better than the turbo-FLASH (1.8 x 1.8 x 8.0 mm 3 ) and EPI (2.0 x 1.8 × 8.0 mm 3 ). Conclusions: Sliding-window CG-HYPR is a promising technique for myocardial perfusion MRI. This technique provides higher image quality with respect to significantly improved SNR and spatial resolution of the myocardial perfusion images, which might improve myocardial perfusion imaging in a clinical setting.

First-pass perfusion MRI is a promising technique to detect ischemic heart disease. Sliding window (SW) conjugate-gradient (CG) highly constrained back-projection reconstruction (HYPR) (SW-CG-HYPR) has been proposed to increase spatial coverage, spatial resolution, and SNR. However, this method is sensitive to respiratory motion and thus requires breath-hold. This work presents a non-model-based motion correction method combined with SW-CG-HYPR to perform free-breathing myocardial MR imaging. Simulation studies were first performed to show the effectiveness of the proposed motion correction method and its independence from the pattern of the respiratory motion. After that, in vivo studies were performed in six healthy volunteers. From all of the volunteer studies, the image quality score of free breathing perfusion images with motion correction (3.11 ± 0.34) is improved compared with that of images without motion correction (2.27 ± 0.32), and is comparable with that of successful breath-hold images (3.12 ± 0.38). This result was further validated by a quantitative sharpness analysis. The left ventricle and myocardium signal changes in motion corrected free-breathing perfusion images were closely correlated to those observed in breath-hold images. The correlation coefficient is 0.9764 for myocardial signals. Bland–Altman analysis confirmed the agreement between the free-breathing SW-CG-HYPR method with motion correction and the breath-hold SW-CG-HYPR. This technique may allow myocardial perfusion MRI during free breathing. Magn Reson Med, 2010. © 2010 Wiley-Liss, Inc.

To compare accelerated real-time two-dimensional (2D) and segmented three-dimensional (3D) cine steady-state free precession magnetic resonance (MR) imaging techniques by using a 32-channel coil with a conventional 2D cine imaging approach for imaging the heart and to evaluate any difference caused by free breathing and breath holding for real-time imaging.In this institutional review board-approved HIPAA-compliant study, 10 healthy volunteers and 22 consecutive patients who were suspected of having or were known to have heart disease underwent cardiac MR imaging by using a 32-channel coil. A conventional multisection 2D real-time cine sequence was used as the reference standard, and three additional accelerated cine sequences were implemented. Volumetric parameters, including ejection fraction (EF), end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume(SV), and myocardial mass, were derived. Wall motion and image quality were assessed by two radiologists. In addition, image time was registered. An additional set of images was acquired by using real-time sequences with free breathing, and quantitative measurements were compared with measurements on images obtained with breath holding. For quantitative analysis, repeated-measures analysis of variance, paired t test, and Bland-Altman analysis were used; for qualitative analysis, nonparametric Wilcoxon signed-rank test was used.All volumetric measurements were significantly correlated with those of the standard sequence (r0.80, P.01). No significant difference among protocols was observed in terms of mean levels for EF or ESV (P.05). However, a significant difference was indicated for EDV and SV (P.01).The accelerated protocols had significantly shorter image times (P.001). Wall motion scores were concordant with the standard sequence in 43-44 (93%-96%) segments for the accelerated protocols, with a strong interreader agreement (intraclass correlation coefficient,or =0.93). No significant difference was identified between real-time protocols with free breathing and those with breath holding for measurement of volumetric parameters.Accelerated real-time 2D and segmented 3D cine techniques are comparable to the standard clinical protocol in assessment of left ventricular global and regional parameters in substantially shorter image times.

The purpose of this study was to evaluate a new free-breathing 3D phase-sensitive inversion-recovery (PSIR) turbo FLASH pulse sequence for the detection of left ventricular myocardial scar.Patients with suspected myocardial scar were examined on a 1.5-T MR scanner for myocardial late enhancement after the administration of gadopentetate dimeglumine using a segmented 2D PSIR turbo FLASH sequence followed by a navigator-gated 3D PSIR turbo FLASH sequence. Image quality was scored by two independent readers using a 4-point Likert scale (0 = poor, nondiagnostic; 1 = fair, diagnostics may be impaired; 2 = good, some artifacts but not interfering in diagnostics; 3 = excellent, no artifacts). Scars were compared quantitatively in volume and graded qualitatively on the basis of size (area) and location.Thirty-three patients were scanned using both techniques. In 25 patients, the quality of the 3D PSIR images was acceptable. Scars were detected in 12 patients. Hyperenhanced scar volumes (p = 0.43), qualitative analysis of scar area (p = 0.78), and scar location (p = 0.68) were similar for both techniques. More small hyperenhanced scars, corresponding mostly to nonischemic distribution patterns, were detected using 3D PSIR than 2D PSIR. Although 2D and 3D results were found to be highly correlated for scar volume, Bland-Altman analysis indicated a systematic smaller infarct volume on the 2D PSIR scans (R(2) = 0.84).Free-breathing 3D PSIR turbo FLASH imaging is a promising technique for the assessment of left ventricular scar particularly for scar quantification and the detection of small nonischemic scars in the myocardium.

The purpose of this study was to compare a navigator gated free breathing 3D Phase Sensitive Inversion Recovery (PSIR) TurboFLASH to an established 2D PSIR TurboFLASH method for detecting myocardial late gadolinium hyperenhanced lesions caused by infiltrative and non-ischemic cardiomyopathy. Under an IRB approved protocol; patients with suspected non-ischemic infiltrative myocardial heart disease were examined on a 1.5T MR scanner for late enhancement after the administration of gadolinium using a segmented 2D PSIR TurboFLASH sequence followed by a navigator-gated 3D PSIR TurboFLASH sequence. Two independent readers analyzed image quality using a four point Likert scale for qualitative analysis (0 = poor, non diagnostic; 1 = fair, diagnostic may be impaired; 2 = good, some artifacts but not interfering in diagnostics, 3 = excellent, no artifacts) and also reported presence or absence of scar. Detected scars were classified based on area and location and also compared quantitatively in volume. Twenty-seven patients were scanned using both protocols. Image quality score did not differ significantly (p = 0.358, Wilcoxon signed rank test) for both technique. Scars were detected in 24 patients. Larger numbers of hyperenhanced scars were detected with 3D PSIR (200) compared to 2D PSIR (167) and scar volume were significant larger in 3D PSIR (p = 0.004). The mean scar volume over all cases was 49.95 cm(3) for 2D PSIR and 70.02 cm(3) for 3D PSIR. The navigator gated free breathing 3D PSIR approach is a suitable method for detecting myocardial late gadolinium hyperenhanced lesions caused by non-ischemic cardiomyopathy due to its complete isotropic coverage of the left ventricle, improving detection of scar lesions compared to 2D PSIR imaging.

First-pass perfusion MRI is a promising technique for detecting ischemic heart disease. However, the diagnostic value of the method is limited by the low spatial coverage, resolution, signal-to-noise ratio (SNR), and cardiac motion-related image artifacts. In this study we investigated the feasibility of using a method that combines sliding window and CG-HYPR methods (SW-CG-HYPR) to reduce the acquisition window for each slice while maintaining the temporal resolution of one frame per heartbeat in myocardial perfusion MRI. This method allows an increased number of slices, reduced motion artifacts, and preserves the relatively high SNR and spatial resolution of the "composite images." Results from eight volunteers demonstrate the feasibility of SW-CG-HYPR for accelerated myocardial perfusion imaging with accurate signal intensity changes of left ventricle blood pool and myocardium. Using this method the acquisition time per cardiac cycle was reduced by a factor of 4 and the number of slices was increased from 3 to 8 as compared to the conventional technique. The SNR of the myocardium at peak enhancement with SW-CG-HYPR (13.83 +/- 2.60) was significantly higher (P0.05) than the conventional turbo-FLASH protocol (8.40 +/- 1.62). Also, the spatial resolution of the myocardial perfection images was significantly improved. SW-CG-HYPR is a promising technique for myocardial perfusion MRI.

Purpose To evaluate the utility of breathhold time-resolved three-directional MR velocity mapping for quantifying the restoration of normal flow patterns in patients after aortic valve-sparing surgery. Materials and Methods Breathhold time-resolved three-directional MR velocity mapping was performed on 13 patients with aortic valve-sparing surgery. Ten healthy volunteers and 12 patients with ascending aortic aneurysm underwent the same MR examination for comparison. Aortic laminar flow, turbulent flow, and the presence of vortical flow in the sinuses of Valsalva were semiquantitatively assessed and statistically compared between the three groups of subjects. Results The average score of laminar flow in the ascending aorta for patients with surgery was not significantly different from that of volunteers (P = 0.210), but was significantly greater than that of patients with aneurysm (P < 0.01). The average score of turbulent flow in patients with surgery was significantly smaller than that of patients with aneurysm (P < 0.01). The presence of systolic vortical flow in the sinuses of Valsalva for patients with surgery was not significantly different from that of healthy volunteers (P = 0.405) and patients with aneurysm (P = 0.238). Conclusion Breathhold time-resolved three-directional MR velocity mapping allows for quantifying flow patterns in the aortic root and ascending aorta. Normal laminar flow in the ascending aorta and vortical flow in the sinuses of Valsalva can be restored in patients after aortic valve-sparing surgery. J. Magn. Reson. Imaging 2009;29:569–575. © 2009 Wiley-Liss, Inc.

INTRODUCTION: Infiltrative myocardial disease (sarcoidosis, amyloid, hypertrophic cardiomyopathy) and non-ischemic inflammatory cardiomyopathy (myocarditis) demonstrate atypical patterns of enhancement on LGE-cMRI, in that they are typically not related to a coronary artery territory and often show a diffuse or patchy hyperenhanced pattern throughout the myocardium [1]. Such hyperenhanced lesions may be missed by conventional 2D imaging due to noncontiguous slices and limited slice coverage. A 3D approach could be more effective for assessing hyperenhanced lesions due to the complete coverage of the left ventricle (LV) with isotropic spatial resolution. The purpose of this study was to compare a navigator gated free breathing 3D Phase Sensitive Inversion Recovery (PSIR) TurboFLASH [2] to an established 2D PSIR turboFLASH method for detecting myocardial hyperenhanced lesions caused by non-ischemic cardiomyopathy. MATERIALS AND METHODS: Under an IRB approved protocol, 19 patients with suspected infiltrative myocardial heart disease and cardiomyopathy [hypertrophic cardiomyopathy (HCM) n= 5, sarcoidosis n= 4, and myocarditis, n=8, amyloid, n=1] were examined on a 1.5T MR scanner (MAGNETOM Avanto, Siemens AG, Erlangen, Germany) were evaluated. The protocol consisted of segmented cine SSFP and delayed enhanced imaging. Delayed images were acquired ten minutes after the administration of contrast agent [0.2 mmol/kg Gadolinium-DTPA (Magnevist, Schering AG, Berlin, Germany)] using a segmented 2D PSIR TurboFLASH sequence followed by a navigator-gated 3D PSIR TurboFLASH sequence [3]. Segmented 2D PSIR TurboFLASH paremeters were: TR/TE: 205/3.2 msec, TI: 270 msec, flip angle: 25°, FOV: 380 x 309 mm, matrix: 156 x 256, pixel size 2.0 x 1.5 mm; slice thickness of 6 mm, bandwidth of 600 Hz per pixel, GRAPPA acceleration factor of 2, k-lines per segment = 25 and for free breathing 3D PSIR parameters were: TE = 1.6 ms, TR = 3.7 ms, TI: 300 msec, flip angle =20°, near isotropic voxels of 1.9 x 1.9 x 2.0 mm acquisition of 40 k-space lines per heartbeat, bandwidth of 500 Hz/pixel with GRAPPA acceleration factor of 2. Quantitative evaluation was carried out by measuring the volume of hyperenhaced lesions for both techniques using scar quantification software -VPT (Viability Processing Toolkit, Siemens Corporate Research, Princeton, NJ) that considered areas with 6 standard deviations above the normal myocardial signal intensity as abnormal. Images were assessed qualitatively by 2 reviewers using the AHA 17-segment model. Image quality was scored using a four point Likert scale (0-poor, non-diagnostic; 1-fair, diagnostic maybe be impaired; 2-good with some artifacts and 3-excellent without artifacts). The total number of lesions per segment was counted. Transmural extent of lesions (subepicardial, midmyocardium, subendocardium) and area per segment were also evaluated. Student t test was used to compare both methods.

A geometrical mismatch between emission and transmission occurs in cardiac PET/CT because of respiratory and cardiac motions. Proposed solutions to this problem include fast CT during free breathing, with or without image alignment, and slow CT. To study this problem, including the variability of human breathing patterns and compliance with instructions, we performed real-time FISP MRI measurements of two free-breathing volunteer subjects. We have developed a method for simulating PET and CT coronal images from these image sequences, and for locating the left cardiac free wall semi-automatically. The PET geometry represents an average over the whole MR examination. The simulated CT geometry represented 28.8 mm axial extent and speeds of 83 mm/sec (fast) and 12 mm/sec (slow), representing a Senation-64 CT scanner running at fast and slow settings. We considered 400 start times for each CT geometry. The free wall was located in each CT image and was compared with the location expected in PET. The error in a given CT scan depends on the geometry, i.e. fast or slow scan, and also on the state of breathing at the time of the scan. A more accurate result can be realized by selecting the best-aligned of two or three fast CT scans. The average errors in fast, slow, best of 2, and best of 3 fast CT scans are respectively 5, 4, 4, and 3 mm. The errors in these scans have 98% likelihood of being less than, respectively, 14, 9, 9, and 7 mm.

The purpose of this study was to evaluate optimal breathing maneuvers that minimize lung parenchymal movement for dynamic contrast-enhanced MRI (DCE-MRI), which requires longer scan times, beyond the limit of a single breath hold. A healthy volunteer was scanned on a 3 T MR scanner using two different breathing maneuvers. In the first, the healthy volunteer was instructed to hold his breath as much as possible and breathe in between breath holds while an image was obtained. In the second, the volunteer was instructed to breathe shallowly and freely throughout the scan. On the obtained images, the excursion of the highest point of the right diaphragm and the pulmonary vessel branches located in the four different anatomic regions of the lung were measured in two orthogonal planes. A patient with a solitary pulmonary nodule (SPN) underwent DCE-MRI utilizing a 2D spoiled gradient-echo (SPGR) sequence while the patient breathed shallowly and freely during the scan. The standard deviations of the excursion of the highest point and selected pulmonary vessels were much smaller during shallow, free breathing maneuver scans than those during breath hold maneuver scans. A dynamic perfusion-fitting curve of the SPN was obtained during the DCE-MRI using shallow free breathing. Shallow, free breathing allows smaller diaphragmatic cranial caudal and lung parenchymal displacements. Therefore, it can be useful during exams where targeting of the lesion is necessary, in studies with long scan times, such as dynamic MRI. This breathing maneuver makes it possible to analyze SPN with DCE-MRI while making use of the advantages of a higher magnetic field in conjunction.

Objectives: To evaluate a 3-dimensional adaptive raw-data filter in reducing streak artifacts in low dose chest computed tomographic (CT) images. Methods: Fourteen adult patients who underwent low dose chest CT examination (parameters: 25 or 50 mAs, 120 kV) on 64-detector CTscanner were included in this study. We prepared 2 sets of contiguous 5-mm thick images by reconstruction with and without 3-dimensional adaptive raw-data filter (filter-processed and unprocessed images). Streak artifacts and visualization of peripheral vessels in both filter-processed and unprocessed images were evaluated using a 5-point scale. Upper, middle, and lower thorax were evaluated separately. Results: The difference in artifact severity was statistically significant in upper and lower thorax (P = 0.002 and 0.03, respectively), whereas it was not significant in middle thorax (P = 0.13). The difference in the visibility of peripheral pulmonary vessels was not statistically significant in all anatomical regions. Conclusions: The 3-dimensional adaptive raw-data filter reduced streak artifacts in low dose chest CT in upper and lower thorax.

Seropositivity of anti-Helicobacter pylori antibody (HP + ) was examined among Japanese Brazilians. The study was announced through 18 Japanese community culture associations in Sao Paulo, Curitiba, Mogi das Cruzes, and Mirandopolis in 2001. Among 969 participants, 963 individuals aged 33 - 69 years were analyzed. The overall HP + % was 48.1% (95% confidence interval, 44.9 - 51.3%). There was no difference in HP + % between 399 males and 564 females (49.6% and 47.0%, respectively). The HP + % increased with age; 35.3% for those aged 33 - 39 years, 46.2% for those aged 40 - 49 years, 46.5% for those aged 50 - 59 years, and 56.9% for those aged 60 - 69 years, but no differences were observed among the generations (Issei, Nisei, and Sansei) for each 10-year age group. Mogi das Cruzes, a rural area, showed a higher HP + %. Length of education was inversely associated with the positivity; the odds ratio (OR) relative to those with eight years or less of schooling was 0.61 (0.42 - 0.89) for those with 12 years or more. The associations with smoking and alcohol drinking were not significant. Fruit intake was associated with the HP + %; the OR relative to everyday intake was 1.38 (1.05 - 1.83) for less frequent intake, while intake frequencies of green tea, miso soup, and pickled vegetables (tsukemono) were not. Multivariate analysis including sex, 10-year age group, residence, education, and fruit intake showed that all factors except sex were significant. This is the largest study of HP infection among Japanese Brazilians, and the results indicated a similar pattern of age-specific infection rate to that for Japanese in Japan.

Background Cardiac MR is often utilized to assess myocardial perfusion [1].Typically, T1 weighted images of the first pass of contrast agent are qualitatively assessed to identify hypo-enhanced regions of the myocardium. Although fully integrated approaches are available to register individual images to eliminate motion the impact on diagnostic accuracy has not been validated in patients [2].

Introduction The diagnostic value of first-pass perfusion MRI is limited by the low spatial coverage, resolution, SNR, and motion artifacts. Sliding-Window Conjugate-Gradient HYPR [1] (SW-CG-HYPR) has been proposed to acquire perfusion images with increased spatial coverage, better spatial resolution, and improved SNR [2]. However, this method is sensitive to the respiratory motion and thus limited to the breath hold. Motion correction may be useful to reduce motion artifacts and allow for free-breathing first-pass perfusion.

Summary The purpose of this study is to evaluate semi quantitative perfusion parameter maps generated based on a fully automated non-rigid motion correction during a first pass myocardial perfusion (FPMP) MRI in patients with suspected coronary artery disease (CAD) or coronary micro vascular disease (CMVD). Background FPMP MRI is commonly used to assess CAD and most recently to assess cardiac involvement in asymptomatic patients with CMVD such as systemic sclerosis and diabetes mellitus. FPMP MRI evaluation relies on visual inspection for qualitative analysis but quantitative analysis of rest and stress perfusion data is desired to improve diagnosis. One main challenge of qualitative analysis includes cardiac and respiratory motion. To minimize this challenge, ap reviously described inline, fully automated motion correction method [Xue, H MICCAI 2009] generates a motion corrected dataset as well as pixel-wise upslope maps. Using the image at a time point selected for peak signal change during the first pass of contrast agent as the template, all other time points were registered into the template coordinate system. We compare qualitatively and quantitatively the original free breathing images and motion correted images with the corresponding maps pixel-wise upslope maps in patients with suspected CAD or CMVD. Methods

Objective The purpose of this study was to evaluate Time-resolved MR venography (TR-MRV) of the pulmonary venous circulation using the time-resolved angiography with interleaved stochastic trajectories (TWIST) method of time-resolved MRA (TR-MRA) and compare it with the more commonly used conventional Contrast enhanced magnetic resonance angiography (CE-MRA) approach in atrial fibrillation patients referred for pre-ablation pulmonary vein mapping. Background Catheter-based ablation of the pulmonary veins prevents recurrence of atrial fibrillation in 70-80% of patients during the first year of follow-up 1,2 . CE-MRA depicts the left atrium and pulmonary veins with high spatial resolution, enabling accurate measurement of pulmonary vein ostia to be made with depiction of their relationship to other structures. 1,3 Conventional CE-MRA however requires timing of contrast enhancement and produces images with overlap of venous and arterial structures, potentially obscuring pulmonary vein ostia. TR-MRA is an alternative to conventional CE-MRA and has been used successfully in other vascular territories. 4 Such an approach may be particularly advantageous in the pulmonary circulation with its rapid arteriovenous transit time, allowing acquisition of pure pulmonary venous phase images with a simpler imaging protocol. Material and methods 26 patients (15 males; age 60.0 ± 12.7y) referred for preablation pulmonary vein mapping underwent both conventional CE-MRA and TR-MRV with TWIST. Imaging was performed on a 1.5 Tesla (MAGNETOM Avanto, Siemens Healthcare) MRI scanner. Source partition and MIP images were evaluated. Quantitative Analysis: Pulmonary vein ostium orthogonal dimensions were measured using double oblique multiplanar reformatting. Qualitative Analysis: For qualitative analysis, both source partition images and MIP images were assessed by two observers. Pulmonary vein conspicuity was scored on a scale of 1-4 (1=poor, 2=fair, 3=good, 4=excellent). The number of pulmonary veins (3 veins= common ostium, 4 veins = normal, 5 veins=accessory vein) was recorded.