Efficacy of Intravitreal Dexamethasone implants in Diabetic Macular Edema Unresponsive to Anti-VEGF Therapy
Keywords:: Diabetic Macular edema, DME, Intravitreal Dexamethasone, Diabetic retinopathy
Background: Diabetic retinopathy is a common microvascular complication of diabetes leading to Diabetic
Macular Edema (DME)and visual impairment in the working age population1
About one third of diabetic
individuals had some degree of Diabetic retinopathy and less than 10% develop DME.
Intravitreal dexamethasone implant in cases unresponsive to anti VEGF therapy has a beneficial role in
improving visual acuity and macular morphology. The possible mechanism of action could be resolution of
edema that was resistant to anti VEGF agents
Aims and Objectives: To determine the efficacy of intravitreal dexamethasone implant for DME
unresponsive to anti Vascular Endothelial Growth factor(VEGF)treatment
Methodology: A retrospective analysis of refractory 21 cases, 30 eyes of DME to primary anti VEGF
treatment was performed to analyze the profile of presentation and treatment outcome to Intravitreal
dexamethsone implants. Ranibizumab (0.5 mg) administered monthly and if, were unresponsive after 5-6
injection were switched to Intravitreal Dexamethasone implants (0.7 mg).
Failure to therapeutic response was characterized by increase in central macular thickness from baseline
finding or no response to treatment. Intravitreal dexamethasone implant was administered every two months
Best corrected visual acuity,Intraocular pressure and central macular thickness was evaluated at baselines
and following intravitreal dexamethasone impant.
Result: The mean age was 56.3± 5.9 years. The mean Intra ocular pressure was 17.3±2.7 mmHg.
The mean anti VEGF treatment sessions was 5.8±1.2. The mean BCVA improved significantly from LogMar
0.76 ±0.16 to 0.67 ±0.19 (p value=0.029) and CMT improved significantly from 431.6 ±100.9µm to 379.1
±80.72µm (p value =0.0005).
Conclusion: Intravitreal dexamethasone is effective in refractory cases of DME unresponsive to anti VEGF
therapy. Optimal evaluation and tailoring therapy with the therapeutic response will be beneficial.