Clinical and angiographic characteristics of multiple dural arteriovenous shunts.

BACKGROUND AND PURPOSE The pathogenesis and characteristics of multiple DAVSs are not well-known. The purpose of this study was to evaluate the angiographic and clinical characteristics of patients with multiple DAVSs with an emphasis on the pathomechanism. MATERIALS AND METHODS One hundred seventy-nine patients with DAVS were reviewed. Patients with ≥ 2 fistulas at anatomically separate sites were included. Multiple DAVSs were categorized into synchronous (simultaneous multiplicity) or metachronous (temporal sequential development of multiplicity) types. The angiographic and clinical characteristics of these lesions were analyzed. RESULTS Fourteen patients were diagnosed with multiple DAVSs (7.8%; synchronous, n = 7; metachronous, n = 7). Thirteen of the 14 patients showed CVR (93%, Borden type II/III). Multiple DAVSs were frequently associated with dural sinus thrombosis (71.4%, n = 10). Synchronous DAVSs developed in association with an occluded sinus (n = 5). De novo metachronous lesions developed in association with thrombosis of a previously patent dural sinus (n = 3) or reopening of an occluded sinus (n = 2). Multiplicity was associated with aggressive initial symptoms in 64.3% (n = 9). The newly developed lesions in the metachronous types were accompanied by hemorrhage (n = 1), neurologic deficit (n = 1), worsening of the initial benign symptoms (n = 2), and incidental detection (n = 3). The mean time interval between the initial diagnosis and de novo lesion detection was 31.3 ± 29.8 months (range, 12-92 months). CONCLUSIONS Multiplicity of DAVSs is associated with poor angiographic and clinical prognosis, requiring an aggressive treatment and management strategy. Sinus thrombosis has a prominent role in the pathomechanism of DAVSs.