Purpose: To develop an efficient 3D affine respiratory motion compensation framework for Cartesian whole‐heart coronary magnetic resonance angiography (MRA).Materials and Methods: The proposed method achieves 100% scan efficiency by estimating the affine respiratory motion from the data itself and correcting the acquired data in the reconstruction process. For this, a golden‐step Cartesian sampling with spiral profile ordering was performed to enable reconstruction of respiratory resolved images at any breathing position and with different respiratory window size. Affine motion parameters were estimated from image‐based registration of 3D undersampled respiratory resolved images reconstructed with iterative SENSE and motion correction was performed directly in the reconstruction using a multiple‐coils generalized matrix formulation method. This approach was tested on healthy volunteers and compared against a conventional diaphragmatic navigator‐gated acquisition using quantitative and qualitative image quality assessment.Results: The proposed approach achieved 47 ± 12% and 59 ± 6% vessel sharpness for the right (RCA) and left (LAD) coronary arteries, respectively. Also, good quality visual scores of 2.4 ± 0.74 and 2.44 ± 0.86 were observed for the RCA and LAD (scores from 0, no to 4, excellent coronary vessel delineation). A not statically significant difference (P = 0.05) was found between the proposed method and an 8‐mm navigator‐gated and tracked scan, although scan efficiency increased from 61 ± 10% to 100%.Conclusion: We demonstrate the feasibility of a new 3D affine respiratory motion correction technique for Cartesian whole‐heart CMRA that achieves 100% scan efficiency and therefore a predictable acquisition time. This approach yields image quality comparable to that of an 8‐mm navigator‐gated acquisition with lower scan efficiency. Further evaluation of this technique in patients is now warranted to determine its clinical use. J. Magn. Reson. Imaging 2015;41:738–746. © 2014 Wiley Periodicals, Inc.

Purpose: To develop a respiratory motion correction framework to accelerate free‐breathing three‐dimensional (3D) whole‐heart coronary lumen and coronary vessel wall MRI.Methods: We developed a 3D flow‐independent approach for vessel wall imaging based on the subtraction of data with and without T2‐preparation prepulses acquired interleaved with image navigators. The proposed method corrects both datasets to the same respiratory position using beat‐to‐beat translation and bin‐to‐bin nonrigid corrections, producing coregistered, motion‐corrected coronary lumen and coronary vessel wall images. The proposed method was studied in 10 healthy subjects and was compared with beat‐to‐beat translational correction (TC) and no motion correction for the left and right coronary arteries. Additionally, the coronary lumen images were compared with a 6‐mm diaphragmatic navigator gated and tracked scan.Results: No significant differences (P > 0.01) were found between the proposed method and the gated and tracked scan for coronary lumen, despite an average improvement in scan efficiency to 96% from 59%. Significant differences (P < 0.01) were found in right coronary artery vessel wall thickness, right coronary artery vessel wall sharpness, and vessel wall visual score between the proposed method and TC.Conclusion: The feasibility of a highly efficient motion correction framework for simultaneous whole‐heart coronary lumen and vessel wall has been demonstrated. Magn Reson Med 77:1894–1908, 2017. © 2016 International Society for Magnetic Resonance in Medicine

MRI is a versatile technique that offers many different options for tissue contrast, including suppressing the blood signal, so‐called black‐blood contrast. This contrast mechanism is extremely useful to visualize the vessel wall with high conspicuity or for characterization of tissue adjacent to the blood pool. In this review we cover the physics of black‐blood contrast and different techniques to achieve blood suppression, from methods intrinsic to the imaging readout to magnetization preparation pulses that can be combined with arbitrary readouts, including flow‐dependent and flow‐independent techniques. We emphasize the technical challenges of black‐blood contrast that can depend on flow and motion conditions, additional contrast weighting mechanisms (T₁, T₂, etc.), magnetic properties of the tissue, and spatial coverage. Finally, we describe specific implementations of black‐blood contrast for different vascular beds.Level of Evidence: 5Technical Efficacy Stage: 5

To propose a 3D quantitative high-resolution T₁ mapping technique, called 3D SASHA (saturation-recovery single-shot acquisition), which combines a saturation recovery pulse with 1D-navigator-based-respiratory motion compensation to acquire the whole volume of the heart in free breathing. The sequence was tested and validated both in a T₁ phantom and in healthy subjects. The 3D SASHA method was implemented on a 1.5T scanner. A diaphragmatic navigator was used to allow free-breathing acquisition and the images were acquired with a resolution of 1.4 × 1.4 × 8 mm³. For assessment of accuracy and precision the sequence was compared with the reference gold-standard inversion-recovery spin echo (IRSE) pulse sequence in a T₁ phantom, while for the in vivo studies (10 healthy volunteers) 3D SASHA was compared with the clinically used 2D MOLLI (3-3-5) and 2D SASHA protocols. There was good agreement between the T₁ values measured in a T₁ phantom with 3D SASHA and the reference IRSE pulse sequences (1111.6 ± 31 msec vs. 1123.6 ± 8 msec, P = 0.9947). Mean and standard deviation of the myocardial T₁ values in healthy subjects measured with 2D MOLLI, 2D SASHA, and 3D SASHA sequences were 881 ± 40 msec, 1181.3 ± 32 msec, and 1153.6 ± 28 msec respectively. The proposed 3D SASHA sequence allows for high-resolution free-breathing whole-heart T₁-mapping with T₁ values in good agreement with the 2D SASHA and improved precision. Level of Evidence: 2 J. Magn. Reson. Imaging 2017