Abstract
Purpose:
Macular edema (ME) related to retinal venous occlusion (RVO) is often persistent or recurrent despite multiple treatments, such as laser photocoagulation, intravitreal triamcinolone (TA), and intravitreal bevacizumab (BEV). Dexamethasone (0.7 mg) implant (DEX) has been proposed to provide more complete and longer lasting improvement in macular edema in these cases. This study sought to investigate this observation further.
Methods:
A retrospective chart review was conducted in RVO-related-ME patients treated with DEX who had experienced persistent and recurrent macular edema despite multiple prior treatments. Number and type of prior treatments, Snellen visual acuity (VA), intraocular pressure (IOP) and OCT central subfield thickness (CSFT) at each DEX implantation were reviewed. This project was reviewed by Indiana University’s IRB and considered exempt.
Results:
31 patients with RVO-related-ME were treated with DEX. The mean duration of the macular edema prior to treatment with DEX was 16 months. Prior to treatment with DEX, this group of eyes received multiple prior treatments, including laser grid treatment in 6 eyes, TA in 1 eye, RAN in 2 eyes and BEV in 29 eyes with 25 of these eyes receiving 3 or more BEV injections. Fifteen of these eyes had received a combination of these therapies. At baseline, the mean VA was 20/215 and the mean CSFT was 534 microns. Once treatment with DEX was initiated, there was improved VA and macular edema in a majority of patients. Some of the patients with limited response or ocular hypertension underwent intermittent BEV injection after the initiation of DEX therapy. At an average first follow up of 6 weeks, the visual acuity improved to 20/171, and the mean CSF improved to 294 microns. CSFT and Visual acuity improvement were maintained throughout the follow up period. By week 32, a mean of 3 DEX implants were administered; visual acuity averaged 20/160 and central subfield thickness measured 380 microns. Intraocular pressure averaged 17 mm Hg.
Conclusions:
DEX improves RVO related-ME refractory to prior treatments and seems to have a longer duration of action. Further study is warranted.