Therapeutic clues in spinal dural arteriovenous fistulas - a 30 year experience of 156 cases.

Background: Spinal dural arteriovenous fistulae (SDAVF) are rare but remain the most common type of spinal vascular malformations. Treatment options for SDAVF include endovascular embolization, microsurgical dissection or a combination of both. But the optimal treatment paradigm has yet to be defined and may well be an individualized interdisciplinary combinatorial approach.

Material and methods: From 1980 to 2008, 156 patients with the diagnosis of SDAVF were treated by neuroradiological and neurosurgical means. Based on the procedure-related complications we retrospectively analyzed our data to elucidate the reasons for endovascular failure and the evolution of the surgical technique.

Results: 156 patients were included in this study. There were 31 (19.9%) female and 125 (80.1%) male patients. Average age at the time of diagnosis was 60.8 years. 102 out of 156 (65.4%) underwent endovascular obliteration, 54 (34.6%) patients were treated primarily by surgery. 134 (85.9%) underwent follow-up examination. A total of 29 (18.6%) out of 156 patients could not be treated successfully by endovascular (9.4%) or surgical (4.1%) means.

Conclusion: Microsurgery can be recommended as the first choice treatment when the fistula's point is unmistakably identified intradurally. Endovascular obliteration may be justifiable in cases with an easy access to a monoradicular feeding artery during diagnostic angiography. Surgery is a definitive treatment with stable long-term results in which procedure-related morbidity is low. During evolution of the combined approach, endovascular coil placement for correct localization of the fistula and the use of intraoperative micro-Doppler was found to be very helpful in increasing the safety of the surgical procedure and minimizing surgical exposure.