Epidural lipomatosis simulating a spinal extradural haematoma

Spinal epidural lipomatosis is a condition in which there is excessive synthesis of normal epidural fat. Most cases are associated with long-term steroid administration1,2 or obesity.3 Occasionally the disorder occurs because of excessive endogenous steroid production in Cushing's syndrome4,5 or suppressed lipolysis in hypothyroidism.6 Idiopathic extradural lipomatosis is rare.7 The disorder usually presents with chronic localized back pain often of several months' duration. We report an unusual case in which a non-obese person, without any of the above risk factors, presented acutely with severe back pain following a lumbar puncture for suspected subarachnoid haemorrhage. The symptoms were subsequently found to be due to spinal epidural lipomatosis. A brief review of the relevant literature is also presented. © 2005 The Royal College of Radiologists.