Abstract
Purpose: :
To investigate relationship between changes of ocular blood flow and plasma nitrate, nitric oxide (NO) derivative, in fresh cases with retinal vein occlusion (RVO) accompanied by macular edema after different treatments.
Methods: :
Prospective study was conducted. Thirty-four consecutive patients with macular edema from RVO (15 male and 19 female, age 40-89 years old) referred to Osaka Medical College from May to October 2011, were enrolled in this study. Macular OCT, plasma nitrate level, and fundus blood flow were measured before and 1- and 3-months after each treatment. Ocular blood flow was measured by laser speckle flowgraphy (LSFG, Fukuoka, Japan). Of all 34 patients, 25 patients were affected with branch retinal vein occlusion, 9 with central retinal vein occlusion, and 3 patients have medical history of glaucoma. Each treatment was the following; 17 patients were treated with laser treatment for avascular lesion, 6 with intravitreal injection of bevacizumab (IVB) and 2 with sub-Tenon triamcinolone acetonide injection. The other cases were not treated and followed with observation.
Results: :
Macular edema was most rapidly improved by IVB; however, decrease in chorioretinal blood flow was seen in some cases after IVB treatment. Plasma nitrate level before and 1 month after the treatment was 108±29μmol/L (mean±SD) and 42±10μmol/L, respectively; and this reduction was significant (P<0.05, paired t-test). Laser treatment for avascular area was also effective for macular edema without significant changes in ocular blood flow.
Conclusions: :
Intravitreal injection of bevacizumab is effective for the treatment of macular edema from RVO; however, bevacizumab may cause a reduction of chorioretinal blood flow compared to other treatments.
Keywords: nitric oxide • blood supply • retina