Syringosubarachnoid shunt for syringomyelia associated with Chiari I malformation.

Abstract

OBJECT: The authors describe the surgical procedures for placing syringosubarachnoid shunts and the results of surgery, as well as the prevention of shunt malfunction. METHODS: The series consisted of 59 patients with syringomyelia associated with Chiari I malformation in whom syringosubarachnoid shunts were placed. Their ages ranged from 4 to 62 years (median 28 years). The follow-up period ranged from 13 to 219 months. The authors principally implanted the shunts in patients with large-sized syringes. Neurological improvement was satisfactory, and postoperative magnetic resonance imaging demonstrated that the syringes had resolved or decreased in size in all patients. Reoperation was necessary in 10 patients who were treated before 1993. CONCLUSIONS: To prevent shunt malfunction, both dorsal root entry zone myelotomy and placement of the syringosubarachnoid shunt tube into the ventral subarachnoid space are useful.