Negative impact of internal limiting membrane peeling in vitreous hemorrhage secondary to retinal vein occlusion with macular ischemia.

Purpose: To investigate the effect of internal limiting membrane (ILM) peeling on visual outcomes and postoperative epiretinal membrane (ERM) after pars plana vitrectomy (PPV) for vitreous hemorrhage (VH) associated with retinal vein occlusion (RVO) with various degrees of macular ischemia.

Methods: We compared the outcomes of eyes that underwent vitrectomy with and without ILM peeling from 2012 to 2021 with a minimum follow-up of 6 months.

Results: 112 charts were analyzed, and 51 eyes met the inclusion criteria. There were 19 eyes with ILM peeling and 32 eyes with non-ILM peeling. Baseline characteristics did not differ significantly. The mean postoperative visual acuity significantly improved at 6 months compared with the mean preoperative visual acuity (P < 0.001). Visual improvement was significantly greater in the non-ILM peeling group(P < 0.05). Without ischemia within the arcade, there was no significant difference in the visual improvement. In patients with ischemia, the visual improvement in the ILM peeling group was significantly worse than that in the non-ILM peeling group. The incidence of postoperative ERM was significantly higher in the non-ILM peeling; however, there was no significant change in postoperative vision due to the presence of ERM.

Conclusions: Vitrectomy either with or without ILM peeling results in visual improvement in patients with VH associated with RVO; however, it should be uniformly avoiding ILM peeling in cases with pre-existing macular ischemia, as it may significantly lead to a deterioration in visual outcomes.

Key messages: What is known Pars plana vitrectomy is effective for visual improvement in vitreous hemorrhage associated with retinal vein occlusion. The incidence of postoperative epiretinal membrane is variable depending on the surgical approach. What is new Avoiding ILM peeling in cases of macular ischemia during vitrectomy is crucial for better visual outcomes. Despite higher rates of epiretinal membrane post-surgery in non-ILM peeled eyes, their visual outcomes remain superior to those with ILM peeling.