Approximately half of patients with retinal vein occlusion (RVO)-associated macular edema (ME) who received treatment with intravitreal injections experienced complete ME resolution in their eyes 3 years after their diagnosis, researchers found in a retrospective cohort study published in Graefes Arch Clin Exp Ophthalmol. They also found that disorganization of retinal inner layers (DRIL) at baseline may predict recurrence of ME (odds ratio = 2.88; P =.013).
Researchers analyzed the change in best-corrected visual acuity (BCVA), central retinal thickness (CRT) and spectral domain optical coherence tomography (SD-OCT) parameters in 104 eyes from 104 consecutive patients at four medical centers in Portugal who had been diagnosed at least 3 years previously (in 2014 or 2015) with RVO-associated ME. Eyes with ME had CRT greater than or equal to 300 μm or intraretinal or subretinal fluid, as detected with SD-OCT. A group of 64 subjects in the study had branch retinal vein occlusion (BRVO) and 40 had central retinal vein occlusion (CRVO). Of the CRVO subjects, 37 were non-ischemic and 3 were ischemic.
Initial treatment consisted of anti-vascular endothelial growth factor (VEGF) agents for 81 eyes, intravitreal corticosteroids (triamcinolone acetonide or dexamethasone sustained-release implant) for 21 eyes and macular focal laser therapy followed by intravitreal treatment for 2 eyes. Of the patients who received treatment with anti-VEGF agents 28 also received intravitreal corticosteroids.
At the 3-year follow-up, 42 of the patients received anti-VEGF treatment and did not present with ME. Additionally, 81 patients experienced a decrease in median BCVA, from .70 logMAR to .40 logMAR, and median CRT, from 539 μm to 299 μm.
Of the 21 patients who received intravitreal corticosteroids as their initial treatment, 9 showed no ME at the follow-up, and the BCVA values retained a median of .70 logMAR while the median CRT improved from 561 μm to 278.5 μm.
Ultimately, 53 eyes (36 of the 64 eyes from the BRVO group and 17 of the 40 eyes from the CRVO group) did not show ME at the 3-year follow-up, as seen via SD-OCT. The median CRT had lowered from 538 μm to 290 μm (P <.001).
The study also identified DRIL as potentially playing an important role in ME pathophysiology in RVO patients. The investigators noted that their subjects with DRIL had a 2.88-fold increased likelihood of maintaining macular edema after 3 years in the univariate analysis. The researchers say they believe DRIL “directly relates to flow abnormalities in the deep capillary plexus.” They added that “affected areas experience persistent hypoxia, continuous and excessive production of VEGF, and consequently ME,” they said.
Limitations of the study included how it may have been subject to biases because it was a retrospective study, differences in clinical practice among the various medical centers that participated and the use of macular focal laser treatments.
Costa JV, Moura-Coelho N, Abreu AC, Neves P, Ornelas M, Furtado MJ. Macular edema secondary to retinal vein occlusion in a real-life setting: a multicenter, nationwide, 3-year follow-up study. Published online September 23, 2020. Graefes Arch Clin Exp Ophthalmol. doi: 10.1007/s00417-020-04932-0