Association of pial venous reflux with hemorrhage or edema in dural arteriovenous fistula

Objective: We investigated whether pial venous reflux (PVR) is associated with hemorrhage or edema in dural arteriovenous fistula (DAVF). Methods: We evaluated the association of hemorrhage or edema with the occurrence of PVR or cortical venous reflux (CVR) in 222 patients with DAVF. We determined whether angiographic findings of PVR or CVR (more than Borden I or Cognard IIa) were associated with symptoms, lesion location, or brain lesion (hemorrhage or edema). We evaluated the lesion progression or the follow-up results after obliteration of the DAVF. Results: Hemorrhage or edema developed in 18% (40/222) of the patients with DAVF and 55% (40/72) of the patients with PVR. There were 2 patterns of PVR associated with hemorrhage or edema: (1) PVR in any particular CVR territory (75%), and (2) direct PVR not via CVR (25%). The presence of brain lesion increased the odds of presence of PVR by 4.09 times compared to the group without brain lesion (95% confidence interval = 1.570–11.394, p = 0.004). Brain edema caused by PVR was reversible after obliteration of the fistula and may have progressed to hemorrhage without proper patient management performed within several weeks after the initial presentation. Conclusions: Our results show that PVR is more closely associated with the hemorrhage or edema than CVR in patients with DAVF. PVR can occur not only as a part of CVR but also directly in certain types of DAVF.