Approaches to obtain quantitative, noninvasive estimates of total cerebral blood volume (tCBV) and cerebral venous blood volume (vCBV) separately in humans are proposed. Two sequences were utilized, including a 3D high-resolution gradientecho (GE) sequence and a 2D multi-echo GE/spin-echo (MEGESE) sequence. Images acquired by the former sequence provided an estimate of background magnetic field variations (ΔB), while images obtained by the latter sequence were utilized to obtain separate measures of tCBV and vCBV with and without contrast agent. Prior to the calculation of vCBV and tCBV, the acquired images were corrected for signal loss induced by the presence of ΔB. vCBV and tCBV were estimated to be 2.46% ± 0.28% and 3.20% ± 0.41%, respectively, after the ΔB correction, which in turn provided a vCBV/tCBV ratio of 0.77 ± 0.04, in excellent agreement with results reported in the literature. Our results demonstrate that quantitative estimates of vCBV and tCBV can be obtained in vivo.
- Cerebral venous blood volume
- Magnetic field inhomogeneities
- Total cerebral blood volume