Premium
RAZER: A pulse sequence for whole‐brain bolus tracking at high frame rates
Author(s) -
Jonathan Sumeeth V.,
Vakil Parmede,
Jeong Yong I.,
Me Rajiv G.,
Ansari Sameer A.,
Carroll Timothy J.
Publication year - 2014
Publication title -
magnetic resonance in medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.696
H-Index - 225
eISSN - 1522-2594
pISSN - 0740-3194
DOI - 10.1002/mrm.24882
Subject(s) - voxel , nuclear medicine , temporal resolution , pulse sequence , standard deviation , nuclear magnetic resonance , physics , mathematics , medicine , radiology , optics , statistics
Purpose To introduce a pulse sequence that obtains whole‐brain perfusion measurements at 1.7 mm isotropic voxel resolution by dynamic susceptibility contrast MRI bolus tracking despite using a temporal resolution of 10.3 s: RAdial kZ‐blipped 3D GRE‐echo‐planar imaging (GRE‐EPI) for whole‐brain pERfusion (RAZER). Methods In RAZER, in‐plane radial and through‐plane 3D GRE‐EPI Cartesian sampling was used to produce a 3D stack‐of‐stars k ‐space. In vivo scans on one healthy volunteer and one patient with Moyamoya disease were performed using RAZER and a typical 2D GRE‐EPI pulse sequence as a reference standard. Agreement in perfusion metrics was reported using linear regression analysis and Bland‐Altman plots. Results Sliding window reconstruction recovered dynamic information lost in the large temporal acquisition window of RAZER. Inline phase correction scans corrected N /2 ghosting artifacts and view‐dependent phase variations. Whole‐brain images of cerebral blood volume, cerebral blood flow, and mean transit time were calculated with RAZER at 1.7 mm isotropic voxel resolution and good reference standard agreement in both subjects when sliding window reconstruction was used ( r 2 > 0.7, mean bias in mean transit time measurements < 0.5 s). Conclusions Despite using a temporal resolution of 10.3 s, in vivo data indicates that RAZER is able to obtain whole‐brain perfusion measurements at 1.7 mm isotropic voxel resolution and good reference standard agreement. Magn Reson Med 71:2127–2138, 2014. © 2013 Wiley Periodicals, Inc.