A theoretical and experimental investigation of vascular-space-occupancy (VASO) blood nulling times: influence of hematocrit and oxygenation on null times and CBV quantification
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چکیده
Blood Nulling Experimental (n=8) T1 (ms) TI (ms) ΔS/S % ΔCBV % # Voxels SNR Arteriole 1747 1114 -1.9±0.6 21.6±3.3 134±28 35±4 Venule 1703 1092 -1.9±0.4 20.7±2.2 132±21 36±6 Micro Avg 1725 1103 -1.7±0.5 18.9±2.7 143±30 37±7 Artery 1671 1077 -1.9±0.4 20.3±2.1 139±22 34±5 Vein 1591 1035 -2.3±0.6 22.9±3.0 130±16 28±3 Macro Avg 1631 1056 -2.2±0.6 23.2±3.1 152±29 34±5 Figure 1. (a) Voxel component recovery curves. (b) Blood recovery curves close to TI. (c) Activation maps. (d) Micro and macrovascular time courses.
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