Lumbar congestive myelopathy mimicking neoplasia without concurrent vascular malformation.

A 78-year-old male presented with congestive myelopathy manifesting as progressive gait disturbance following conservative therapy for lumbar spinal canal stenosis, with suspected spinal cord tumor in the conus medullaris. His past medical history was unremarkable and he was not aware of any traumatic injury in the back or infectious disease. On admission, he had clumsy hand, moderate paraparesis, significant sensory disturbance below the L5 level, and severe vesicorectal dysfunction. The deep tendon reflex was promoted in the upper extremities, but poorly induced in the lower extremities. Blood examination found no abnormalities including values of tumor markers. Cerebral, cervical, and thoracic magnetic resonance (MR) imaging revealed no contributory pathology without spondylotic change at the C3-C6 levels. Lumbar MR imaging showed fusiform swelling of the cord from the T10 to T12-L1 levels, with rimlike enhancement at the T12-L1 levels by gadolinium. The patient underwent surgery. Intraoperatively, the dorsal surface of the affected cord was pale, not swollen, and sparsely vascularized without tortuous vessels. Midline myelotomy caused escape of creamy material that was identified as necrotic neural tissue. A collapsed vessel, located on the surface of the cord, was histologically identified as a thrombosed vein. The histological findings were compatible with spinal infarction caused by congestive myelopathy. Whole craniospinal and iliac angiography performed postoperatively failed to reveal any dural and paraspinal vascular malformation. His paraparesis, sensory disturbance, and vesicorectal dysfunction improved significantly after surgery. Congestive myelopathy may be caused by various angiographically occult etiologies other than dural arteriovenous fistula.