Huge intradural ossification caused by a mature spinal teratoma: case report.

OBJECTIVE: Huge intradural ossifications in the spine are quite rare. We report for the first time a patient with a huge intradural ossification caused by a mature teratoma at the conus medullaris. CLINICAL PRESENTATION: A 68-year-old woman presented with low back pain and gait disturbance. Computed tomographic and magnetic resonance imaging revealed a huge ossification at the tip of the conus medullaris. INTERVENTION: We performed L1 and L2 laminectomy and removed the mass completely. The pathological diagnosis was mature teratoma with remarkable ossification. CONCLUSION: This unusual case of intradural ossification demonstrated regressive changes in a mature teratoma. Despite its tight adhesion to the conus medullaris and cauda equina, the ossified tumor was atraumatically removed with an ultrasonic aspirator.