Treatment Modalities for Dural Arteriovenous Fistulas (DAVFs) According to Venous Drainage Patterns

Objective : The purpose of this study was to analyze the clinical presentation and available therapeutic modalities for treating dural arteriovenous fistulas (DAVFs), according to the angiographic features. (Ed note : "...fistulas (DAVFs), and we wanted to determine their correlation with the angiographic features?") Methods : We retrospectively reviewed the records of 10 DAVFs patients who were treated at our institution from June 2001 to January 2008. The nature and cause of the clinical presentation was reviewed. The angiographic findings were categorized according the patterns of venous drainage, which were based on the classification system described by Cognard et al.7 The goals (eradication of the AV fistulas vs. interruption of the cortical venous reflux) and the modalities of treatment (endovascular treatment, surgery or radiation therapy) were analyzed according to the angiographic classifications. The angiographic results and clinical outcomes were also assessed. Results : According to Cognard's classification, 2 cases were type I, 3 were type II b, 1 was type II a+b, 2 were typeIII and 2 were typeV, respectively. The initial presenting symptoms included headache (5 cases), pulsatile tinnitus (1 case), visual disturbance (1 case), seizure (1 case), mental change (3 cases) and progressive quadriplegia (1 case). Trans-arterial embolization was adapted as an initial treatment method in 6 cases (1 type I, 1 type II b, 1 type II a+b, 1 type III and 2 type V) with the goal of fistula obliteration or limited interruption of the cortical venous reflux. The procedure was successful in 5 cases (83.3%) and additional craniotomy was necessary in 1 case. Surgery was performed in 4 cases (40%) as the primary treatment modality because of the lack of endovascular accessibility or the complexity of the anatomical relationships. The surgical results were successful in all cases and no further endovascular treatment was required. Among the 9 patients who experienced the angiographically determined disappearance of DAVFs, 6 patients were rated as 5 for the Glasgow outcome scale (GOS) score, 2 patients were rated as 4 and 1 patient was rated as 3. One patient with angiographically determined incomplete obliteration showed a GOS of 3. Conclusions : The venous drainage pattern is a single most important factor for determining the clinical presentation, the treatment planning and the outcome. An endovascular procedure can be chosen as an initial treatment modality when feasible. Surgery is required for more complex and aggressive lesions with cortical venous reflux.