Fernando F Paiva1, Alberto Tannús, S Lalith Talagala, Afonso C Silva. 1. Cerebral Microcirculation Unit, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke (NINDS), National Institutes of Health (NIH), Bethesda, Maryland, USA.
Abstract
PURPOSE: To obtain cerebral perfusion territories of the left, the right, and the posterior circulation in humans with high signal-to-noise ratio (SNR) and robust delineation. MATERIALS AND METHODS: Continuous arterial spin labeling (CASL) was implemented using a dedicated radio frequency (RF) coil, positioned over the neck, to label the major cerebral feeding arteries in humans. Selective labeling was achieved by flow-driven adiabatic fast passage and by tilting the longitudinal labeling gradient about the Y-axis by theta = +/- 60 degrees . RESULTS: Mean cerebral blood flow (CBF) values in gray matter (GM) and white matter (WM) were 74 +/- 13 mL . 100 g(-1) . minute(-1) and 14 +/- 13 mL . 100 g(-1) . minute(-1), respectively (N = 14). There were no signal differences between left and right hemispheres when theta = 0 degrees (P > 0.19), indicating efficient labeling of both hemispheres. When theta = +60 degrees , the signal in GM on the left hemisphere, 0.07 +/- 0.06%, was 92% lower than on the right hemisphere, 0.85 +/- 0.30% (P < 1 x 10(-9)), while for theta = -60 degrees , the signal in the right hemisphere, 0.16 +/- 0.13%, was 82% lower than on the contralateral side, 0.89 +/- 0.22% (P < 1 x 10(-10)). Similar attenuations were obtained in WM. CONCLUSION: Clear delineation of the left and right cerebral perfusion territories was obtained, allowing discrimination of the anterior and posterior circulation in each hemisphere. (c) 2008 Wiley-Liss, Inc.
PURPOSE: To obtain cerebral perfusion territories of the left, the right, and the posterior circulation in humans with high signal-to-noise ratio (SNR) and robust delineation. MATERIALS AND METHODS: Continuous arterial spin labeling (CASL) was implemented using a dedicated radio frequency (RF) coil, positioned over the neck, to label the major cerebral feeding arteries in humans. Selective labeling was achieved by flow-driven adiabatic fast passage and by tilting the longitudinal labeling gradient about the Y-axis by theta = +/- 60 degrees . RESULTS: Mean cerebral blood flow (CBF) values in gray matter (GM) and white matter (WM) were 74 +/- 13 mL . 100 g(-1) . minute(-1) and 14 +/- 13 mL . 100 g(-1) . minute(-1), respectively (N = 14). There were no signal differences between left and right hemispheres when theta = 0 degrees (P > 0.19), indicating efficient labeling of both hemispheres. When theta = +60 degrees , the signal in GM on the left hemisphere, 0.07 +/- 0.06%, was 92% lower than on the right hemisphere, 0.85 +/- 0.30% (P < 1 x 10(-9)), while for theta = -60 degrees , the signal in the right hemisphere, 0.16 +/- 0.13%, was 82% lower than on the contralateral side, 0.89 +/- 0.22% (P < 1 x 10(-10)). Similar attenuations were obtained in WM. CONCLUSION: Clear delineation of the left and right cerebral perfusion territories was obtained, allowing discrimination of the anterior and posterior circulation in each hemisphere. (c) 2008 Wiley-Liss, Inc.
Authors: J A Detre; W Zhang; D A Roberts; A C Silva; D S Williams; D J Grandis; A P Koretsky; J S Leigh Journal: NMR Biomed Date: 1994-03 Impact factor: 4.044
Authors: Renata F Leoni; Fernando F Paiva; Byeong-Teck Kang; Erica C Henning; George C Nascimento; Alberto Tannús; Dráulio B De Araújo; Afonso C Silva Journal: Transl Stroke Res Date: 2011-11-16 Impact factor: 6.829