Role of Vitrectomy in Nontractional Refractory Diabetic Macular Edema

Currently, the gold standard of diabetic macular edema (DME) treatment is anti-vascular endothelial growth factor (VEGF) injections, although a percentage of patients do not respond optimally. Vitrectomy with or without internal limiting membrane (ILM) peeling is a well-established treatment for DME cases with a tractional component while its role for nontractional cases is unclear. The aim of this study is to evaluate the role of vitrectomy with or without ILM peeling in nontractional refractory DME.

We performed a retrospective review of twenty-eight eyes with nontractional refractory DME treated with vitrectomy at San Giuseppe Hospital, Milan, between 2016 and 2018. All surgeries were performed by a single experienced vitreoretinal surgeon. In 43.4% of cases, the ILM was peeled. Best corrected visual acuity and optical coherence tomography (OCT) scans were assessed preoperatively and at 6, 12, and 24 months post-vitrectomy.

The mean central macular thickness improved from 413.1 ± 84.4 to 291.3 ± 57.6 μm at two years (p < 0.0001). The mean logarithm of the minimum angle of resolution logMAR best-corrected visual acuity (BCVA) improved after two years, from 0.6 ± 0.2 to 0.2 ± 0.1 (p < 0.0001). We found no difference between ILM peeling vs. no ILM peeling group in terms of anatomical (p = 0.8) and visual outcome (p = 0.3). Eyes with DME and subfoveal serous retinal detachment (SRD) at baseline had better visual outcomes at the final visit (p = 0.001).

We demonstrated anatomical and visual improvement of patients who underwent vitrectomy for nontractional refractory DME with and without ILM peeling. Improvement was greater in patients presenting subretinal fluid preoperatively.