MR imaging of a ruptured intraspinal dermoid tumour with fat droplets in the central spinal canal.

We report a patient with intramedullary ruptured spinal dermoid tumour. The MR imaging revealed an intra-medullary lumbar mass heterogenous in intensity in all sequences. Fat droplets were observed in the subarachnoid space as well as in the dilated central spinal canal. Fat droplets in the subarachnoid space are frequently seen in the rupture of intraspinal dermoid tumours; however, fat droplets within the central canal is quite rare and was unexpected. Magnetic resonance imaging is a useful tool in the determination of spinal pathologies before they become large enough to cause severe symptoms and/or morbidity.