An overlooked cause of subdural effusions.

A middle-aged man presented with progressive confusion. Initial brain CT was misinterpreted to have 'cerebral atrophy and bilateral subdural effusions' by the emergency physician, and the patient was admitted to a medical ward for further investigation. Two days later, the patient experienced acute neurological deterioration, and burr hole drainage was performed to relieve the effusions. It was later confirmed that the effusions were caused by intracranial hypotension secondary to spinal cerebrospinal fluid leakage. The patient improved on conservative treatment with no lasting neurological sequela.