Spinal extradural arachnoid cyst in a child-a case report.

Extradural spinal arachnoid cysts are rare lesions. They frequently communicate with the subarachnoid space through a defect in the dura. Symptoms result from compression of the spinal cord or nerve roots. The treatment of choice is complete surgical excision. We report the case of a 12-year-old girl with extradural spinal arachnoid cyst who had complete surgical excision with good outcome.