Purpose:
To investigate the utility of intravitreal bevacizumab for treatment of macular edema due to retinal vein occlusion(RVO) in previously treated eyes.
Methods:
Retrospective chart review of consecutive patients treated with intravitreal bevacizumab for macular edema due to RVO was conducted. Inclusion criteria were eyes having optical coherence tomography(OCT) measurement on day of injection with at least one follow up OCT. Response to bevacizumab injection was determined by a percent change from initial central foveal thickness. Initial, best and final OCT values were recorded. Eyes were separated into 2 groups: previously treated and previously untreated for macular edema due to CRVO or BRVO. Previous treatments included intravitreal or posterior subtenon’s triamcinolone acetate injection and focal or grid laser. A paired t-test was used to compare the mean pre and post-injection OCT thickness for each group. A t-test was used to compare the mean percentage OCT change of the 2 groups. Significance was assumed to be P<0.05.
Results:
15 patients met inclusion criteria; 7 were previously untreated and 8 previously treated. Mean central foveal thickness changed from 412.6µm to 298.9µm(best) and 341.5µm(final) for previously untreated eyes. This corresponds to a decrease by 27.6% and 17.2%. Mean central foveal thickness changed from 358.4µm to 281.4µm(best) and 369µm(final) for the previously treated group. This corresponds to a decrease by 21.5% and an increase by 3%. There was no statistically significant change in foveal thickness in any of the groups. A t-test found no significant difference in the mean percent change in OCT thickness for the 2 groups from initial to best(P=0.463) or final(P=0.347) OCT values. See table 1.
Conclusions:
This data shows no significant difference in response to intravitreal bevacizumab between previously treated and untreated eyes for treatment of macular edema from RVO. The data suggests that previously untreated patients may respond better; a more clear relationship may be established with a larger sample size.
Keywords: injection • drug toxicity/drug effects • macula/fovea