Surgical Treatment of Syringomyelia

The surgical approach to syringomyelia is controversial. In this study, the authors evaluated the results of various operative procedures applied in 31 patients with syringomyelia. Syringomyelia was associated with Chiari malformation in 17 cases, with spinal adhesive arachnoiditis in nine, with trauma in three, and with epidural arachnoid cyst in one. One case was idiopathic. A total of 38 operations were performed. Syringosubarachnoid shunting was applied in 17 patients, syringoperitoneal shunting in 11, terminal syringostomy in three, ventriculoperitoneal shunting in three, lumboperitoneal shunting in two, foramen magnum decompression (suboccipital craniectomy plus upper cervical laminectomy) and terminal syringostomy in one, and foramen magnum decompression with syringosubarachnoid shunting in one. The postoperative follow-up period ranged from 2 to 55 months (average, 26 months). Of the 31 patients, 23 showed neurological improvement, five were unchanged, and three deteriorated. Among the last three, one patient with Chiari malformation developed shunt malfunction due to arachnoiditis after syringosubarachnoid shunting. In two patients with syringomyelia secondary to adhesive arachnoiditis, the spinal cord was damaged by extensive separation of the arachnoid membrane at surgery. On the basis of the results in these 31 cases, the authors conclude that syringosubarachnoid shunting is effective for syringomyelia associated with Chiari malformation if syringomyelia is responsible for the clinical symptoms. Post-traumatic syringomyelia and syringomyelia secondary to adhesive arachnoiditis should be treated by syringoperitoneal shunting. If hydrocephalus is present, ventriculoperitoneal shunting is indicated. Finally, terminal syringostomy is no more effective than syringosubarachnoid or syringoperitoneal shunting.