Intracerebral haemorrhage. Accuracy of computerised transverse axial scanning in predicting the underlying aetiology.

The diagnostic accuracy of computerised transverse axial tomography in predicting the pathology underlying cases of nontraumatic intracerebral haematoma has been reviewed. A 160 X 160 matrix was used and the scans of one hundred patients whose diagnoses had been confirmed by either angiographic or post-mortem examination were studied. In the absence of any clinical information a diagnosis of either cerebral aneurysm or primary intracerebral haemorrhage could be made with an accuracy of 90%. The haematomas most likely to be misinterpreted are those associated with angiomas and tumours, and these two lesions were responsible for six out of the ten incorrect diagnoses. In predicting the site of a ruptured aneurysm accuracy ranged from 100% for those involving the anterior cerebral artery complex to 66% for those few haematomas associated with aneurysms of the internal carotid/proximal middle cerebral artery aneurysm complex.