Abstract
Purpose:
The duration of action of sustained release dexamethasone implant in eyes affected by macular edema in retinal vein occlusion (RVO) is object of controversy. Nevertheless, its determination is crucial in order to plan appropriate re-treatment and follow-up strategies. Therefore, we performed an analysis of a large series of treatments in order to establish the duration of action of dexamethasone implant and to monitor the long-term changes in visual acuity and macular thickness.
Methods:
Consecutive eyes with macular edema due to retinal vein occlusion treated with intravitreal dexamethasone implant were included in the study. One hundred forty-one consecutive treatments were analyzed. Patients were followed-up on a monthly basis and retreated when edema occurred, based on optical coherence tomography data. The primary outcome measure is time to relapse (days). The secondary outcomes are changes in best-corrected visual acuity, central retinal thickness and number of treatments during follow-up<br />
Results:
Forty eyes were included in the study (16 central retinal vein occlusion, 4 hemispheric retinal vein occlusion, 20 branch retinal vein occlusion). Mean follow-up was 26 months and patients received a mean of 3.5 treatments. Mean time to macular edema relapse was 190 (range 90-800) days after the first treatment and 150 (range 80-150) days after the following injections. Mean visual acuity change was +3.8 (n 40), +0.9 (n 40), and -0.5 (n 17) letters after 1, 12, and 24 months, respectively. Mean central retinal thickness decreased by 255, 167, and 174 μm at the same timepoints. Intraocular pressure rise was noted in 10 eyes (25%) and required topical therapy.
Conclusions:
Intravitreal therapy with sustained release dexamethasone implant produces functional and morphological benefits in patients with macular edema due to retinal vein occlusion. The time to relapse reported in the present study supports the utilization of an as-needed re-treatment protocol with monthly follow-up starting from month 3.