Concomitant Thoracic Spinal Dural Arteriovenous Fistula and Spinal Cavernous Malformation

Both spinal dural arteriovenous fistula (SDAVF) and spinal cavernous malfor-mation (SCM) are uncommon vascular malformations. To our knowledge, such a case of SDAVF concomitant with SCM has not been reported. We encountered a case of a 55-year-old man who had weakness and numbness in both lower extremities. Magnetic resonance imaging showed a round-shape lesion iden-tified as a cavernous malformation in the middle segment of the thoracic spine, with spinal edema and obvious flow voids. Diagnostic angiography revealed an SDAVF fed by the right T7 radicular artery with venous drainage. The intra-medullary venous hypertension due to fistula was suspected of inducing the formation of SCM. This case may provide new insight into the pathogenesis of SCM.