Yang Ji1, Dongshuang Lu1, Yinghua Jiang2, Xiaoying Wang2, Yuguang Meng3, Phillip Zhe Sun1,3,4. 1. Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts, USA. 2. Clinical Neuroscience Research Center, Department of Neurosurgery, Tulane University School of Medicine, New Orleans, Louisiana, USA. 3. Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, Georgia, USA. 4. Department of Radiology and Imaging Sciences, Emory University School of Medicine, Atlanta, Georgia, USA.
Abstract
PURPOSE: To develop fast multi-slice apparent T1 (T1app ) mapping for accurate cerebral blood flow (CBF) quantification with arterial spin labeling (ASL) MRI. METHODS: Fast multi-slice T1app was measured using a modified inversion recovery echo planar imaging (EPI) sequence with simultaneous application of ASL tagging radiofrequency (RF) and gradient pulses. The fast multi-slice T1app measurement was compared with the single-slice T1app imaging approach, repeated per slice. CBF was assessed in healthy adult Wistar rats (N = 5) and rats with acute stroke 24 hours after a transient middle cerebral artery occlusion (N = 5). RESULTS: The fast multi-slice T1app measurement was in good agreement with that of a single-slice T1app imaging approach (Lin's concordance correlation coefficient = 0.92). CBF calculated using T1app reasonably accounted for the finite labeling RF duration, whereas the routine T1 -normalized ASL MRI underestimated the CBF, particularly at short labeling durations. In acute stroke rats, the labeling time and the CBF difference (ΔCBF) between the contralateral normal area and the ischemic lesion were significantly correlated when using T1 -normalized perfusion calculation (R = 0.844, P = .035). In comparison, T1app -normalized ΔCBF had little labeling time dependence based on the linear regression equation of ΔCBF = -0.0247*τ + 1.579 mL/g/min (R = -0.352, P = .494). CONCLUSIONS: Our study found fast multi-slice T1app imaging improves the accuracy and reproducibility of CBF measurement.
PURPOSE: To develop fast multi-slice apparent T1 (T1app ) mapping for accurate cerebral blood flow (CBF) quantification with arterial spin labeling (ASL) MRI. METHODS: Fast multi-slice T1app was measured using a modified inversion recovery echo planar imaging (EPI) sequence with simultaneous application of ASL tagging radiofrequency (RF) and gradient pulses. The fast multi-slice T1app measurement was compared with the single-slice T1app imaging approach, repeated per slice. CBF was assessed in healthy adult Wistar rats (N = 5) and rats with acute stroke 24 hours after a transient middle cerebral artery occlusion (N = 5). RESULTS: The fast multi-slice T1app measurement was in good agreement with that of a single-slice T1app imaging approach (Lin's concordance correlation coefficient = 0.92). CBF calculated using T1app reasonably accounted for the finite labeling RF duration, whereas the routine T1 -normalized ASL MRI underestimated the CBF, particularly at short labeling durations. In acute stroke rats, the labeling time and the CBF difference (ΔCBF) between the contralateral normal area and the ischemic lesion were significantly correlated when using T1 -normalized perfusion calculation (R = 0.844, P = .035). In comparison, T1app -normalized ΔCBF had little labeling time dependence based on the linear regression equation of ΔCBF = -0.0247*τ + 1.579 mL/g/min (R = -0.352, P = .494). CONCLUSIONS: Our study found fast multi-slice T1app imaging improves the accuracy and reproducibility of CBF measurement.
Authors: Nikola Stikov; Mathieu Boudreau; Ives R Levesque; Christine L Tardif; Joëlle K Barral; G Bruce Pike Journal: Magn Reson Med Date: 2014-02-27 Impact factor: 4.668
Authors: David L Thomas; Mark F Lythgoe; Louise van der Weerd; Roger J Ordidge; David G Gadian Journal: J Cereb Blood Flow Metab Date: 2006-02 Impact factor: 6.200
Authors: David C Alsop; John A Detre; Xavier Golay; Matthias Günther; Jeroen Hendrikse; Luis Hernandez-Garcia; Hanzhang Lu; Bradley J MacIntosh; Laura M Parkes; Marion Smits; Matthias J P van Osch; Danny J J Wang; Eric C Wong; Greg Zaharchuk Journal: Magn Reson Med Date: 2014-04-08 Impact factor: 4.668