CEREBRAL BLOOD-VOLUME MAPS WITH DYNAMIC CONTRAST-ENHANCED T1-WEIGHTEDFLASH IMAGING - NORMAL VALUES AND PRELIMINARY CLINICAL-RESULTS

Purpose: In this article we investigate the application of a method th at uses the relaxation effect of bolus-like injected Gd-DTPA to quanti fy regional cerebral blood volume (rCBV), The aim of the study was to determine if the method provides correct rCBV values in healthy subjec ts as well as to obtain additional diagnostic information for patients with a glioma or stroke. Method: Twenty healthy subjects, 12 patients with brain infarctions, and 18 patients with gliomas were examined. A series of 64 sequential images of one slice was recorded during bolus transit with a FLASH sequence. The measured signal intensity-time cur ves were converted pixel-wise to concentration-time curves from which the rCBV images were calculated applying the indicator dilution method . Results: An average value for gray and white matter of 4.4 +/- 1.6 v ol% was obtained for the group of healthy subjects. The grading of the tumors could be classified according to the differences of their corr esponding rCBV values. Fifty percent of the infarct patients had to be excluded from the analysis in the acute phase due to mispositioning o f the slice and data degradation by gross motion artifact. Different r CBV values were found for areas that develop later into gliotic scars or cystic necrosis. Conclusion: The proposed method is easy to apply i n clinical routine MR investigations and provides valuable information for noninvasive, preoperative assessment of tumor grading, It can als o provide additional criteria for estimating the histological outcome and with it the degree of ischemia in stroke patients.