TISSUE CHARACTERIZATION OF INTRACRANIAL TUMORS - THE VALUE OF MAGNETIZATION-TRANSFER AND CONVENTIONAL MRI

We performed MRI on 85 patients with intracranial tumours to evaluate quantitative analysis in tumour characterisation. Signal intensities w ere measured on standard T2- and T1-weighted images, G2-enhanced T1-we ighted images and magnetisation transfer (MT) images. Statistically si gnificant differences between tumour types were observed, but overlapp ing reduces their value. T2-weighted imaging was superior to T1-weight ed imaging for tumour characterisation. Quantification of Gd enhanceme nt was useful in the diagnosis of pituitary adenomas and haemangioblas tomas, but of minor importance in other tumours, because of large nons pecific variation. The contribution of MT contrast to tumour character isation resembled that of T2 contrast. However, MT imaging was superio r to other sequences in the classification of intraaxial tumours. Low- grade astrocytomas, haemangioblastomas and craniopharyngiomas could be differentiated from other tumours on the basis of MT contrast. Reliab le discrimination between meningiomas, high-grade astrocytomas and met astases was not possible by any of the methods.