In one year, cerebral angiograms were performed for intracranial haemo
rrhage (ICH) on 334 patients. No cause for haemorrhage could be identi
fied in 41 (12 %), 30 of whom had predominantly subarachnoid (SAH) and
11 predominantly parenchymal haemorrhage (PH). These patients were pr
ospectively examined by cranial MRI 1-6 weeks after the ictus. The MRI
studies were positive in 7 patients (17 %). In the 30 patients examin
ed after SAH, 2 studies were positive, showing an aneurysm in one case
and a brain stem lesion of uncertain aetiology in the other. In those
examined after PH, cavernous angiomas were shown in 2, a tumour in 1
and a vascular malformation in another; useful diagnostic information
was thus obtained in 36 % of this group.