Extra-intradural Spinal Meningioma: A Case Report.

Extradural spinal meningiomas are uncommon, and their pathophysiology is not entirely understood. Here, we present the case of a 49-year-old woman with low back and left leg pain of 5 years duration. Magnetic resonance imaging revealed a mass, 1.8-cm in size, with rim enhancement in the spinal canal at the T12 level and extending into the left T12-L1 foramen. In the surgical field, the mass presented with the characteristics of an extra-intradural spinal meningioma. The patient underwent a T12 total laminectomy. A linear durotomy was performed at the midline, and the intradural portion was removed. The extradural portion was not separable from the adjacent dura and the left T12 root, and it was removed by dural excision. Pathological examination confirmed the diagnosis of psammomatous meningioma. We also conducted a literature review of similar cases. Based on our experience with this case, we believe that it is important to clearly distinguish extradural meningiomas from other types of tumors as misdiagnosis can change the operative plan. The long term prognosis of extradural meningiomas is not clear but total excision is thought to be essential.