[Microsurgical treatment of intradural dorsal arteriovenous fistulas]

To evaluate efficacy of microsurgical hemilaminectomy approach and use of intraoperative indocyanine green videoangiography for patients with intradural dorsal arteriovenous fistula.

Medical records and follow-up data of 24 patients who were microsurgically treated at a single institution for intradural dorsal arteriovenous fistula between January 2004 and August 2008 were retrospectively reviewed. Preoperatively DSA was performed for definite diagnosis. All patients were evaluated with the Aminoff and Logue scale. Preoperative, 4 patients had excellent spinal condition having mean score of 1.0; 8 cases had good spinal condition with mean score of 3.4; 9 cases had average spinal condition with mean score of 6.9; 3 cases had poor spinal condition with mean score of 10.0. Twenty two cases had one feeder while 2 cases had two feeding arteries. All the patients underwent microsurgical hemilaminectomy via a posterior approach. Two patients received complemented surgery because of the recurrence of the lesion after embolisation failed. Three patients received intraoperative indocyanine green videoangiography. Combined followed-up imaging and myelonic function were used for evaluating followed-up data.

Mean follow up was done up to 36 months. Followed-up imaging didn't reveal any residual lesion or its recurrence. Spinal functional assessment using Aminoff and Logue scale showed 16 patients of excellent outcome and had mean score of 0.7; 4 had good outcome having mean score of 4.8; 3 was of average nature with mean score of 6.7; 1 had poor outcome with 9.0 scores. With the surgical treatment, 16 cases were cured, 6 were improved and 2 cases had no change according to synthetic curative effect.

Microsurgical treatment, especially the microsurgical hemilaminectomy via a posterior approach, is effective treatment intradural dorsal arteriovenous fistula. Intraoperative indocyanine green videoangiography is a simple auxiliary tool for intraoperative quality control and favorable surgical outcomes.