MR-BASED CEREBRAL BLOOD-VOLUME MAPS AS A DIAGNOSTIC-TOOL FOR BRAIN-TUMORS

Purpose: Today contrast enhanced MR imaging is a reliable method for d etecting mostly distinguishing between different histological types of tumours. In this study we use a MR-based method to measure the region al cerebral blood volume (rCBV). Using this technique we try to judge the grading and vitality of the tumours. Methods: 26 patients with var ious types of brain tumours were examined. To calculate rCBV-maps of o ne slice, low-dosed Gd-DTPA was injected as a bolus. Using the relaxat ion effect the obtained signal intensity-time curves were converted pi xel-wise into rCBV images. For the tumours rCBV-ratios were calculated relative to the corresponding area in the contralateral hemisphere. R esults. In the investigated group all tumours were detected on the bas is of a raised rCBV-ratio. Since only vital parts of the tumour are pe rfused, the rCBV maps may be used to determine the place of biopsy. Co nclusions: The differential diagnosis of all histological tumour types was not possible on the basis of rCBV values. Distinction between low grade and high grade gliomas was also not significant. However, a low grade glioma can be excluded if the morphological images definitely i ndicate an astrocytoma and if the rCBV-ratio was higher than 2.