Purpose
To compare the progression of epiretinal membrane (ERM) formation in diabetic macular edema (DME) patients treated with Ozudex injection versus other intravitreal medications.
Methods
This retrospective interventional study was conducted in 12 eyes from 8 patients with DME receiving Ozurdex injection and 19 control eyes with DME receiving treatment with ranibizumab, bevacizumab, and/or triamcinolone acetonide between January 1, 2009 and December 4, 2014. The patients' demographic data and macular morphology examined by spectral domain optical coherence tomography (SD-OCT) were collected. The vertical and horizontal extensions of macular epiretinal membrane prior to injection and 12 months after injection were measured with ImageJ in a blinded fashion by two retina specialists. The variables were studied using student's t-test.
Results
At baseline there was no statistical difference between the two of groups in the mean ERM dimensions. At 12 months after injection, the horizontal ERM measurement increased by a mean of 641.74 ± 785.24µm in the Ozurdex group (paired t-test: p = 0.020273) compared to 234.48 ± 644.23µm in the control group (paired t-test: p = 0.139992). The summarized vertical and horizontal ERM measurement increased by a mean of 1605.08 ± 2426.46µm in the Ozurdex group (paired t-test: p = 0.050622), compared with 523.22 ± 980.44µm in the control group (paired t-test: p = 0.036154). The mean increase in the vertical ERM measurement was 936.34 ± 1737.47µm in the Ozurdex group; the difference was not statistically significant (p = 0.093) compared to 288.77 ± 482.75µm in the control group (paired t-test: p = 0.020617)
Conclusions
The study demonstrates a statistically significant increase in ERM dimensions in patients with DME treated with intravitreal dexamethasone implant (Ozurdex) compared to those treated with other intravitreal medications. Further investigation is needed to investigate the cause and clinical consequences of this finding.