Whole brain quantitative CBF and CBV measurements using MRI bolus tracking: Comparison of methodologies

Three different deconvolution techniques for quantifying cerebral blood flo w (CBF) from whole brain T*(2)-weighted bolus tracking images were implemen ted (parametric Fourier transform P-FT, parametric single value decompositi on P-SVD and nonparametric single value decomposition NP-SVD), The techniqu es were tested on 206 regions from 38 hyperacute stroke patients. In the P- FT and P-SVD techniques, the tissue and arterial concentration time curves were fit to a gamma variate function and the resulting CBF values correlate d very well (CBFP-FT = 1.02 . CBFP-SVD, r(2) = 0.96). The NP-SVD CBF values (i.e., original unfitted curves were used) correlated well with the P-FT C BF values only when a sufficient number of time series volumes were acquire d to minimize tracer time curve truncation (CBFP-FT x 0.92 . CBFNP-SVD, r(2 ) = 0.88), The correlation between the fitted CBV and the unfitted CBV valu es was also maximized in regions with minimal tracer time curve truncation (CBV,, = 1.00 . CBVunfit, r(2) = 0.89). When a sufficient number of time se ries volumes could not be acquired (due to scanner limitations) to avoid tr acer time curve truncation, the P-FT and P-SVD techniques gave more reliabl e estimates of CBF than the NP-SVD technique. (C) 2000 Wiley-Liss, Inc.