Spinal angiolipoma mimicking extradural lipomatosis

Spinal angiolipoma is a rare, benign tumour. More than 90% of cases arise extradurally. The authors report an extradural spinal angiolipoma in a 54-year-old man. Conventional T1-weighted and T2-weighted magnetic resonance imaging (MRI) demonstrated an excessive amount of extradural adipose tissue posteriorly, extending from the level of the third to the ninth thoracic vertebra. The signal intensity within the spinal cord was normal. These findings were initially misinterpreted as being of little clinical significance. When the patient's condition deteriorated, myelography was performed, and extradural compression of the thecal sac was demonstrated. At surgery spinal angiolipoma was confirmed. The ease with which the MRI features of this lesion can be overlooked, as well as imaging strategies to avoid this pitfall, are discussed.