Outcome and prognostic factors in the surgical treatment of spinal dural arteriovenous fistulas. A long-term study.

From a total of 78 patients surgically treated for a spinal dural arteriovenous fistula, in whom long-term follow-up was available, 25 have been reviewed. Their outcome at different postoperative stages and the long-term prognostic factors is discussed. Excision or coagulation of the nidus, as well as disconnection of the draining vein offers better results in the long-term than clipping of the draining vein alone. Prolonged duration of symptoms and poor functional status before surgical treatment adversely affect the long-term outcome. Age at the time of surgery did not influence outcome in this study. In the long-term all patients tended to show a moderate, but definite functional decline. This is unlikely to be due entirely to recanalization and may represent a more generalized haemodynamic abnormality of the cord together with the effects of age on the original damage.