Microsurgical treatment of cranial and spinal dural arteriovenous fistulas for acute occlusion: a single institution's experience.

[OBJECTIVES] To determine the success rate of primary microsurgical treatment of both cranial and spinal dural arteriovenous fistulas (cdAVFs and sdAVFs).

[METHODS] Data of 40 consecutive patients (mean age, 64.5 years; range, 35-88 years) who underwent microsurgical treatment for a diagnosed cdAVF/sdAVF at a single academic institution were retrospectively obtained. General patient information, such as age on the day of surgery and sex, patient charts, admission protocols, operating reports, and discharge protocols were reviewed. Outcomes, including modified Rankin Scale (mRS) scores and the rate of complete occlusion confirmed by a postoperative angiography were analyzed.

[RESULTS] The overall post-treatment occlusion rate was 100% in sdAVFs and 92% in cdAVFs. The most common presentation of cdAVFs was intracerebral hemorrhage (67%), followed by headache (53%) and vertigo (33%). The main symptoms of sdAVFs were sensory deficits, paresis, gait abnormalities, and incontinence. Additional endovascular treatment after primary surgery was needed in seven (47%) patients with cdAVF and one patient (4%) with sdAVF. All sdAVFs were classified as Cognard grade V, while six (40%) cdAVFs were Cognard grade III, eight (54%) were grade IV and one (6%) was grade V. Complications included cerebrospinal fluid (CSF) fistulas, CSF circulation disorders, meningitis, and epidural and intracerebral hemorrhages. Furthermore, sdAVF showed higher rates of clinical improvement than cdAVF (56% vs. 47%).

[DISCUSSION] Microsurgery resulted in complete occlusion in most cases of sdAVFs. However, additional endovascular treatment was necessary in nearly 50% of patients with cdAVF. Therefore, combined treatment in cranial cdAVF seems to be the desired strategy.