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Assessment of regional cerebral blood flow by dynamic susceptibility contrast MRI using different deconvolution techniques

Regional cerebral blood flow (rCBF) was assessed using dynamic susceptibility‐contrast MRI at 1.5 T. A simultaneous dual FLASH pulse sequence and Gd‐DTPA‐BMA (0.3 mmol/kg b.w.) were used for examination of 43 volunteers, measuring rCBF in frontal white matter (WM) and in gray matter in the thalamus (GM). Arterial input functions (AIFs) were registered 1) in the carotid artery and 2) in an artery within the GM/WM slice. The measured concentration‐vs.‐time curve was deconvolved with the AIF using both Fourier Transform (FT) and Singular Value Decomposition (SVD). Relative rCBF was given by the height of the deconvolved response curve. For each volunteer, eight different rCBF maps were calculated, representing different combinations of deconvolution techniques, AIFs, and filters. The average GM–WM rCBF ratios ranged from 2.0–2.2, depending on methodology. Absolute rCBF was 68 ± 28 ml/(min 100 g) in GM and 35 ± 13 ml/(min 100g) in WM (mean ± SD, n = 39). GM–WM rCBF ratios obtained using SVD were 6–10% higher than corresponding ratios obtained using FT. Magn Reson Med 43:691–700, 2000. © 2000 Wiley‐Liss, Inc.