Iatrogenic spinal epidermoid tumour associated with tuberous sclerosis. A diagnostic pitfall.

We present a case of spinal epidermoid tumour that was probably caused by lumbar punctures. The tumour was detected on MRI in a child with tuberous sclerosis complaining of atypical low back pain. Preoperatively the tumour was considered to be a cystic astrocytoma of ependymoma of the conus terminalis. The association of tuberous sclerosis with a spinal tumour is rare but has been recorded in the literature. The diagnosis was an epidermoid tumour (E.T.). The MRI appearances were unusual for a spinal ET: the signal intensity changes were different from those reported in the literature and the presence of calcification and cavitation has not yet been reported. This case represents a diagnostic pitfall, since both entities were unrelated.