Contribution of MRI in the diagnosis of haemangioblastomas.

Magnetic resonance imaging (MRI) patterns of 11 haemangioblastomas examined with a 1.5-T scanner are described. MRI was as effective as contrast-enhanced CT in the detection of vascular tumour components, but was less sensitive than angiography. MRI was superior to CT in delineating the exact extent of the lesions, for example contact with the arachnoid surface. Even if a cystic tumour component is absent, MRI can provide helpful criteria for differential diagnosis; in particular, T2 values allow differentiation from meningiomas. In three patients additionally administered gadolinium (Gd) diethylenetriaminepenta-acetic acid (DTPA) the angiomatous parts of the tumour showed a remarkable decrease in T1 value, but the time dependence of the enhancement was not the same as that seen in dynamic CT.