The zebra sign: an unknown known.

A 65-year-old woman became obtunded following routine laminectomy and was found to have bilateral cerebellar haemorrhage and convexity subarachnoid haemorrhage. We discuss the possible mechanisms of remote cerebellar haemorrhage—cerebellar haemorrhage that develops after spinal or intracranial surgery—giving rise to the ’zebra sign' and the possible mechanism of convexity subarachnoid haemorrhage in this context [corrected]. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/