A Case of Hemorrhagic Cavernoma of the Lumbar Nerve Root

There have been 26 cases of surgically resected intradural extramedullary cavernomas in the lumbar nerve root. Only 4 cases were accompanied by intratumoral hemorrhage. A 63-year-old woman presented with right lower limb paresthesia that had begun 14 and 6 months ago, followed by gradually worsening motor paralysis over the last 2 months. Magnetic resonance imaging revealed a homogeneous intradural extramedullary lesion with niveau at the L4 level. The affected L4 nerve root on the right had thinned and was strongly adherent to the surrounding gliosis plane due to repeated hemorrhage. Therefore, we had no choice but to sacrifice the nerve root, which was thought to be the origin of the tumor. Consequently, total tumor resection was performed. The pathological diagnosis was cavernoma. This is the fifth hemorrhagic case of a cavernoma originating from the lumbar nerve root. Although intradural extramedullary cavernomas in the lumbar nerve roots are rare, they can present with hemorrhage. It should be considered in the differential diagnosis when radiographic imaging shows findings suggestive of niveau.