Spinal dural arteriovenous fistulas: an underestimated cause of myelopathy.

13 patients with spinal dural arteriovenous fistulas (DAVF) diagnosed in our Institution have been the object of this study. The necessity to include the disease in the differential diagnosis with other pathologies affecting the lower thoracic cord, particularly in middle-aged and old males, is emphasized. Involvement of the spinal cord was always demonstrable on magnetic resonance studies, but pathologic vessels suggesting the possibility of DAVF were seldom recognizable. Myelography still remains an important complementary method. Spinal angiography is essential, taking into account that the fistula can be located far from the spinal cord. The therapy consisting in embolization in 7 cases and embolization associated with surgery in 6 cases led to improvement or stabilization of the disease in all cases. Our cases are discussed in comparison with the literature.