TY - JOUR T1 - Fast Contrast-Enhanced 4D MRA and 4D Flow MRI Using Constrained Reconstruction (HYPRFlow): Potential Applications for Brain Arteriovenous Malformations JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. SP - 1049 LP - 1055 DO - 10.3174/ajnr.A4245 VL - 36 IS - 6 AU - W. Chang AU - Y. Wu AU - K. Johnson AU - M. Loecher AU - O. Wieben AU - M. Edjlali AU - C. Oppenheim AU - P. Roca AU - J. Hald AU - B. Aagaard-Kienitz AU - D. Niemann AU - C. Mistretta AU - P. Turski Y1 - 2015/06/01 UR - http://www.ajnr.org/content/36/6/1049.abstract N2 - BACKGROUND AND PURPOSE: HYPRFlow is a novel imaging strategy that provides fast, high-resolution contrast-enhanced time-resolved images and measurement of the velocity of the entire cerebrovascular system. Our hypothesis was that the images obtained with this strategy are of adequate diagnostic image quality to delineate the major components of AVMs.MATERIALS AND METHODS: HYPRFlow and 3D TOF scans were obtained in 21 patients with AVMs with correlative DSA examinations in 14 patients. The examinations were scored for image quality and graded by using the Spetzler-Martin criteria. Mean arterial transit time and overlap integrals were calculated from the dynamic image data. Volume flow rates in normal arteries and AVM feeding arteries were measured from the phase contrast data.RESULTS: HYPRFlow was equivalent to 3D-TOF in delineating normal arterial anatomy, arterial feeders, and nidus size and was concordant with DSA for AVM grading and venous drainage in 13 of the 14 examinations. Mean arterial transit time on the AVM side was 0.49 seconds, and on the normal contralateral side, 2.53 seconds with P < .001. Across all 21 subjects, the mean arterial volume flow rate in the M1 segment ipsilateral to the AVM was 4.07 ± 3.04 mL/s; on the contralateral M1 segment, it was 2.09 ± 0.64 mL/s. The mean volume flow rate in the largest feeding artery to the AVM was 3.86 ± 2.74 mL/s.CONCLUSIONS: HYPRFlow provides an alternative approach to the MRA evaluation of AVMs, with the advantages of increased coverage, 0.75-second temporal resolution, 0.68-mm isotropic spatial resolution, and quantitative measurement of flow in 6 minutes.CE-VIPRcontract-enhanced time-resolved vastly undersampled isotropic radial projection reconstructionHYPR LRhighly constrained projection reconstruction using a local reconstruction convolution kernelPC-VIPRphase-contrast MRA using vastly undersampled isotropic radial projection reconstructionHYPRFlowhighly constrained projection reconstruction using PC-VIPR flow images for the constraint ER -