Highly time-resolved 4D MR angiography using golden-angle radial sparse parallel (GRASP) MRI

• Type of Material: Article
• Authors: Adam Goldman-Yassen, Emory University; Eytan Raz, NYU Langone Health; Maria J Borja, NYU Langone Health; Duan Chen, New York–Presbyterian Hospital; Anna Derman, Maimonides Medical Center; Siddhant Dogra, NYU Langone Health; Kai Tobias Block, NYU Langone Health; Seena Dehkharghani, Emory University
• Language: English
• Date: 2022-09-05
• Publisher: NATURE PORTFOLIO
• Publication Version: Final Published Version
• Copyright Statement: © The Author(s) 2022
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1038/s41598-022-18191-y
• Title of Journal or Parent Work: SCIENTIFIC REPORTS
• Volume: 12
• Issue: 1
• Start Page: 15099
• End Page: 15099
• Keywords: Multidisciplinary Sciences; CONTRAST; Science & Technology; COMBINATION; Science & Technology - Other Topics
• Research Categories: Health Sciences, Radiology

Abstract

Current dynamic MRA techniques are limited by temporal resolution and signal-to-noise penalties. GRASP, a fast and flexible MRI technique combining compressed-sensing, parallel imaging, and golden-angle radial sampling, acquires volumetric data continuously and can be reconstructed post hoc for user-defined applications. We describe a custom pipeline to retrospectively reconstruct ultrahigh temporal resolution, dynamic MRA from GRASP imaging obtained in the course of routine practice. GRASP scans were reconstructed using a custom implementation of the GRASP algorithm and post-processed with MeVisLab (MeVis Medical Solutions AG, Germany). Twenty consecutive examinations were scored by three neuroradiologists for angiographic quality of specific vascular segments and imaging artifacts using a 4-point scale. Unsubtracted images, baseline-subtracted images, and a temporal gradient dataset were available in 2D and 3D reconstructions. Distinct arterial and capillary phases were identified in all reconstructions, with a median of 2 frames (IQR1-3 and 2–3, respectively). Median rating for vascular segments was 3 (excellent) in all reconstructions and for nearly all segments, with excellent intraclass correlation (range 0.91–1.00). No cases were degraded by artifacts. GRASP-MRI obtained in routine practice can be seamlessly repurposed to produce high quality 4D MRA with 1–2-s resolved isotropic cerebrovascular angiography. Further exploration into diagnostic accuracy in disease-specific applications is warranted.