Dural Arteriovenous Fistula within Superior Sagittal Sinus Wall with Direct Cortical Venous Drainage: A Systematic Literature Review

Abstract

AbstractDural arteriovenous fistulas (DAVFs) located within superior sagittal sinus (SSS) wall with direct cortical venous drainage are rare. They are also known as variant DAVF (vDAVF) and form a special subgroup of DAVFs. Their chance of presenting with aggressive features is high compared with transverse sigmoid sinus fistula. They drain directly into cortical veins (Borden type 3, Cognard type III and IV). A systematic English literature review of SSS vDAVF was made. Systematic literature review revealed a total of 31 published cases. These were commonly seen in male population, (24 males, 77.41%, 24/31). Average age of patients was 54 years. A total of 24 patients (77.41%, 24/31) had aggressive clinical presentations with 13 patients (41.93%, 13/31) having intracranial hemorrhages (ICH). Two patients had rebleeding (15.38%, 2/13). Middle portion of SSS was commonly involved (15 cases, 75%). A total of 25 (96.15%, 25/26) cases had patent SSS. Most of the fistulas were idiopathic (65.38%, 17/26), with trauma being a frequent etiological factor (26.92%, 7/26). Venous ectasia was seen in 19 patients (59.37%, 19/32). Middle meningeal arterial (MMA) supply was seen in all patients (100%, 26/26), with bilateral MMA supply in 21 cases (80.76%), and unilateral in 5 cases (19.23%). Twenty patients (62.50%, 20/32) received only endovascular treatment (EVT), while four patients had EVT followed by surgery (12.5%, 4/32). Transarterial route via MMA was the preferred treatment option (79.16%). Complete obliteration of fistulas was noted in all cases (100%, 30/30). No immediate complication was noted after EVT. As much as 92.30% patients showed good recovery. Thus, SSS vDAVF forms a special subgroup of DAVF, with aggressive presentation, and warrants urgent treatment. EVT is effective treatment option and can produce complete obliteration.