Tentorium cerebelli subdural haematoma complicating subarachnoid haemorrhage

Acute subdural haematoma (SDH) as a result of aneurysmal rupture is a rare event. We report a tentorium cerebelli SDH, secondary to a ruptured aneurys m which we believe is unique in the literature. This report also gives furt her support to the theory that a sentinel bleed causes inflammation and adh esion between the aneurysm and arachnoid as the underlying pathology in the se unusual subdural haematomas. Since the first report of acute SDH from a ruptured aneurysm by Hasse in 1855, only about 150 further cases have been reported in the literature. We describe a further case, but at an as yet un reported site with radiological evidence of a sentinel bleed.