Quantitative analysis of cerebral microvascular hemodynamics with T2-weighted dynamic MR imaging

The purpose of this study was to quantify cerebral microvascular hemodynami cs with Ta-weighted dynamic susceptibility contrast-enhanced magnetic reson ance imaging (DSC- MRI) using a half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence. We performed T2-weighted DSC-MRI with HASTE seq uence in 19 normal subjects. After bolus injection of gadopentetate dimeglu mine, HASTE images of two sections were acquired for the simultaneous creat ion of concentration-time curves in the internal carotid artery and in brai n tissue. Absolute regional cerebral blood volume (rCBV), regional cerebral blood now (rCBF), and mean transit time (MTT) values of brain tissue were calculated on a base of the indicator dilution theory, and all values were corrected on the assumption that rCBF of white matter is constant in 22 mL/ 100 g tissue/min without age-dependent alteration. A decrease in rCBV and r CBF of gray matter was age dependent, while rCBV of white matter did not sh ow significant change with aging. The mean rCBF value in gray matter was 37 .3 +/- 8.4 mL/100 g tissue/min. The mean rCBV value was 4.1 +/- 0.8 mL/100 g tissue in gray matter and 2.9 + 0.4 mL/100 g tissue in white matter. The rCBV and rCBF values of gray and white matter obtained from T2-weighted DSC -MRI with HASTE sequence were slightly lower than the published data calcul ated by gradient-echo sequence. We were able to perform absolute quantifica tions of the capillary blood volume and now, using a HASTE sequence, which would not have been possible with a gradient-echo sequence. This technique provides a new method for estimating cerebral microvascular hemodynamics, ( C) 1999 Wiley-Liss, Inc.