Gamma Knife surgery for low-flow cavernous sinus dural arteriovenous fistulas.

Abstract

OBJECT: The purpose of this study was to assess the efficacy of Gamma Knife surgery (GKS) for treating cavernous sinus dural arteriovenous fistulas (CSDAVFs).

METHODS: Of the 4123 GKSs performed between May 1992 and March 2009, 890 procedures were undertaken to treat vascular lesions. In 24 cases, the vascular lesion that was treated was a dural arteriovenous fistula, and in 6 of these cases, the lesion involved the cavernous sinus. One of these 6 cases was lost to follow-up, leaving the other 5 cases (4 women and 1 man) to comprise the subjects of this study. All 5 patients had more than 1 ocular symptom, such as ptosis, chemosis, proptosis, and extraocular movement palsy. In all patients, CSDAVF was confirmed by conventional angiography. Three patients were treated by GKS alone and 2 patients were treated by GKS combined with transarterial embolization. The median follow-up period after GKS in these 5 cases was 30 months (range 9-59 months).

RESULTS: All patients experienced clinical improvement, and their improvement in ocular symptoms was noticed at a mean of 17.6 weeks after GKS (range 4-24 weeks). Two patients received embolization prior to GKS but did not display improvement in ocular symptoms. An average of 20 weeks (range 12-24 weeks) was needed for complete improvement in clinical symptoms. There were no treatment-related complications during the follow-up period.

CONCLUSIONS: Gamma Knife surgery should be considered as a primary, combined, or additional treatment option for CSDAVF in selected cases, such as when the lesion is a low-flow shunt without cortical venous drainage. For those selected cases, GKS alone may suffice as the primary treatment method when combined with close monitoring of ocular symptoms and intraocular pressure.