CT appearance of subdural haemorrhage

Last reviewed 01/2018

The characteristic picture of a CT scan of a subdural haemorrhage is one of a biconcave, concentric shaped, area of increased density spreading around the surface of the cerebral hemisphere. The contralateral ventricle may dilate owing to obstruction at the foramen of Munro.

After 10-20 days, the subdural haematoma becomes isodense with brain. Later it becomes relatively hypodense.