Alteration of plasma von Willebrand factor in the treatment of retinal vein occlusion with cystoid macular edema

Abstract

AbstractRetinal vein occlusion (RVO) is a major retinal disease accompanied by venous thrombosis. Although several studies have proposed an association between venous thrombosis and von Willebrand factor (VWF), the association between RVO and VWF remains unclear. We aimed to investigate the association between RVO and VWF and the alteration of VWF levels under the anti-vascular endothelial growth factor (VEGF) treatment. We enrolled 55 patients with RVO involved cystoid macular edema. They received intravitreal injection of anti-VEGF drugs, either ranibizumab or aflibercept. We examined the clinical data, measured plasma VWF: antigen (VWF: Ag) and plasma a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 (ADAMTS13) activity (ADAMTS13: AC) and analyzed them to identify variabilities during the treatment. At the baseline there was no significant difference between the RVO group and age-matched controls in both VWF: Ag and ADAMTS13: AC levels but ADAMTS13:AC was significantly lower in central RVO (CRVO) than in branch RVO (BRVO) (P = 0.015). In BRVO, the negative correlation was found between VWF: Ag and central choroidal thickness (CCT) (r = −0.51, P < 0.001). In BRVO after the anti-VEGF treatment, VWF: Ag decreased significantly from 134% at the baseline to 109% at 1 day after (P = 0.002) and to 107% at 1 month after (P = 0.030). In contrast, ADAMTS13: AC showed no significant difference during this period. In BRVO at 1 month after treatment, we found a negative correlation between VWF: Ag and CCT (r = −0.47, P = 0.001). Our findings suggest an association between VWF and CCT in patients with BRVO, thus the measurement of VWF may be useful for evaluating the disease activity and prognosis.