Impact of Intravitreal Ranibizumab on Vessel Functionality in Patients With Retinal Vein Occlusion.

Abstract

To investigate the short-term effects of intravitreal ranibizumab on retinal vessel functionality in patients with retinal vein occlusion (RVO). Prospective, interventional case series. We enrolled 11 eyes of 11 consecutive treatment-naïve patients with macular edema secondary to RVO. All patients underwent a complete ophthalmic evaluation, including optical coherence tomography and dynamic and static retinal vessel analysis, using the Dynamic Vessel Analyzer (Imedos, Jena, Germany) before (baseline) and 1 week and 1 month after administration of intravitreal ranibizumab. Investigations of RVO patients were compared to 11 eyes of age- and sex-matched control subjects. In RVO patients, dynamic analysis showed a significant increase of mean venous dilation from +2.46% ± 1.03% at baseline to +3.96% ± 1.3% at 1 week (P = .001). At 1 week mean maximum venous and arterial dilations did not differ from those of control subjects. Static analysis showed a mean overall significant decrease of central retinal artery equivalent and central retinal vein equivalent from baseline to 1 week (from 174.8 ± 22.5 measurement units [MU] to 167.2 ± 26.7 MU [P = .04], and from 228.4 ± 20.7 MU to 217.3 ± 22.8 [P = .0002]). Mean central retinal artery equivalent in healthy control subjects was 175.9 ± 10.45 MU, not significantly different from baseline, week 1, and month 1 of RVO eyes. Conversely, mean central retinal vein equivalent was 195.5 ± 9.91 MU in healthy control subjects, significantly different from baseline, week 1, and month 1 of RVO eyes. Using the Dynamic Vessel Analyzer in patients with RVO, we found that intravitreal ranibizumab increased vein dilation (dynamic analysis) and had a vasoconstrictive effect on both arteries and veins (static analysis).