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Background: Bright‐blood lumen and black‐blood vessel wall imaging are required for the comprehensive assessment of aortic disease. These images are usually acquired separately, resulting in long examinations and potential misregistration between images. Purpose: To characterize the performance of an accelerated and respiratory motion‐compensated three‐dimensional (3D) cardiac MRI technique for simultaneous contrast‐free aortic lumen and vessel wall imaging with an interleaved T2 and inversion recovery prepared sequence (iT2Prep‐BOOST). Study Type: Prospective. Population: A total of 30 consecutive patients with aortopathy referred for a clinically indicated cardiac MRI examination (9 females, mean age ± standard deviation: 32 ± 12 years). Field Strength/Sequence: 1.5‐T; bright‐blood MR angiography (diaphragmatic navigator‐gated T2‐prepared 3D balanced steady‐state free precession [bSSFP], T2Prep‐bSSFP), breath‐held black‐blood two‐dimensional (2D) half acquisition single‐shot turbo spin echo (HASTE), and 3D bSSFP iT2Prep‐BOOST. Assessment: iT2Prep‐BOOST bright‐blood images were compared to T2prep‐bSSFP images in terms of aortic vessel dimensions, lumen‐to‐myocardium contrast ratio (CR), and image quality (diagnostic confidence, vessel sharpness and presence of artifacts, assessed by three cardiologists on a 4‐point scale, 1: nondiagnostic to 4: excellent). The iT2Prep‐BOOST black‐blood images were compared to 2D HASTE images for quantification of wall thickness. A visual comparison between computed tomography (CT) and iT2Prep‐BOOST was performed in a patient with chronic aortic dissection. Statistical Tests: Paired t‐tests, Wilcoxon signed‐rank tests, intraclass correlation coefficient (ICC), Bland–Altman analysis. A P value < 0.05 was considered statistically significant. Results: Bright‐blood iT2Prep‐BOOST resulted in significantly improved image quality (mean ± standard deviation 3.8 ± 0.5 vs. 3.3 ± 0.8) and CR (2.9 ± 0.8 vs. 1.8 ± 0.5) compared with T2Prep‐bSSFP, with a shorter scan time (7.8 ± 1.7 minutes vs. 12.9 ± 3.4 minutes) while providing a complementary 3D black‐blood image. Aortic lumen diameter and vessel wall thickness measurements in bright‐blood and black‐blood images were in good agreement with T2Prep‐bSSFP and HASTE images (<0.02 cm and <0.005 cm bias, respectively) and good intrareader (ICC > 0.96) and interreader (ICC > 0.94) agreement was observed for all measurements. Data Conclusion: iT2Prep‐BOOST might enable time‐efficient simultaneous bright‐ and black‐blood aortic imaging, with improved image quality compared to T2Prep‐bSSFP and HASTE imaging, and comparable measurements for aortic wall and lumen dimensions. Evidence Level: 2. Technical Efficacy: Stage 2. [ABSTRACT FROM AUTHOR]

Background: Dixon cardiac magnetic resonance fingerprinting (MRF) has been recently introduced to simultaneously provide water T1 , water T2 , and fat fraction (FF) maps.Purpose: To assess Dixon cardiac MRF repeatability in healthy subjects and its clinical feasibility in a cohort of patients with cardiovascular disease.Population: T1MES phantom, water-fat phantom, 11 healthy subjects and 19 patients with suspected cardiovascular disease.Study Type: Prospective.Field Strength/sequence: 1.5T, inversion recovery spin echo (IRSE), multiecho spin echo (MESE), modified Look-Locker inversion recovery (MOLLI), T2 gradient spin echo (T2 -GRASE), 6-echo gradient rewound echo (GRE), and Dixon cardiac MRF.Assessment: Dixon cardiac MRF precision was assessed through repeated scans against conventional MOLLI, T2 -GRASE, and PDFF in phantom and 11 healthy subjects. Dixon cardiac MRF native T1 , T2 , FF, postcontrast T1 and synthetic extracellular volume (ECV) maps were assessed in 19 patients in comparison to conventional sequences. Measurements in patients were performed in the septum and in late gadolinium enhanced (LGE) areas and assessed using mean value distributions, correlation, and Bland-Altman plots. Image quality and diagnostic confidence were assessed by three experts using 5-point scoring scales.Statistical Tests: Paired Wilcoxon rank signed test and paired t-tests were applied. Statistical significance was indicated by *(P < 0.05).Results: Dixon cardiac MRF showed good overall precision in phantom and in vivo. Septal average repeatability was ~23 msec for T1 , ~2.2 msec for T2 , and ~1% for FF. Biases in healthy subjects/patients were measured at +37 msec*/+60 msec* and -8.8 msec*/-8 msec* when compared to MOLLI and T2 -GRASE, respectively. No statistically significant differences in postcontrast T1 (P = 0.17) and synthetic ECV (P = 0.19) measurements were observed in patients.Data Conclusion: Dixon cardiac MRF attained good overall precision in phantom and healthy subjects, while providing coregistered T1 , T2 , and fat fraction maps in a single breath-hold scan with similar or better image quality than conventional methods in patients.Level Of Evidence: 2.Technical Efficacy Stage: 2. [ABSTRACT FROM AUTHOR]

Purpose: To develop a novel gadolinium‐free model‐based quantitative magnetization transfer (qMT) technique to assess macromolecular changes associated with myocardial fibrosis. Methods: The proposed sequence consists of a two‐dimensional breath‐held dual shot interleaved acquisition of five MT‐weighted (MTw) spoiled gradient echo images, with variable MT flip angles (FAs) and off‐resonance frequencies. A two‐pool exchange model and dictionary matching were used to quantify the pool size ratio (PSR) and bound pool T2 relaxation (T2B). The signal model was developed and validated using 25 MTw images on a bovine serum albumin (BSA) phantom and in vivo human thigh muscle. A protocol with five MTw images was optimized for single breath‐hold cardiac qMT imaging. The proposed sequence was tested in 10 healthy subjects and 5 patients with myocardial fibrosis and compared to late gadolinium enhancement (LGE). Results: PSR values in the BSA phantom were within the confidence interval of previously reported values (concentration 10% BSA = 5.9 ± 0.1%, 15% BSA = 9.4 ± 0.2%). PSR and T2B in thigh muscle were also in agreement with literature (PSR = 10.9 ± 0.3%, T2B = 6.4 ± 0.4 us). In 10 healthy subjects, global left ventricular PSR was 4.30 ± 0.65%. In patients, PSR was reduced in areas associated with LGE (remote: 4.68 ± 0.70% vs. fibrotic: 3.12 ± 0.78 %, n = 5, P <.002). Conclusion: In vivo model‐based qMT mapping of the heart was performed for the first time, with promising results for non‐contrast enhanced assessment of myocardial fibrosis. [ABSTRACT FROM AUTHOR]