This is a case of an 'Acute Spine' meriting out of hours on call MR imaging.

The differential is for an intradural, extramedullary mass includes:

1. spinal meningioma
2. spinal schwannoma
3. spinal neurofibroma

Spinal surgery was undertaken.   The histological sample was reported as a hemangiopericytoma. In this case, this is likely to be derived from the dura with the now commonly used term of solitary fibrous tumor of the dura most accurately describing its origin. In the new (2016) WHO classification of CNS tumors solitary fibrous tumors and hemangiopericytomas are combined into the one entity, retaining the two terms in recognition of the variable macroscopic presentation