Comparison of Fovea-Sparing (Button-Hole) and Conventional Internal Limiting Membrane Peeling in Retinal Arterial Macroaneurysm Rupture: Visual and Anatomical Outcomes

Purpose: To compare surgical outcomes of foveal-sparing internal limiting membrane (ILM) peeling (button-hole) with conventional ILM peeling in patients with retinal arterial macroaneurysm (RAM) rupture accompanied by sub-ILM hemorrhage (sub-ILMh) and subretinal hemorrhage (SRH), focusing on visual and anatomical results and postoperative macular hole (MH) formation. Methods: A retrospective review was conducted on 42 eyes (42 patients) who underwent vitrectomy for RAM rupture with sub-ILMh and SRH between September 2016 and December 2023. Patients were divided into two groups: conventional ILM peeling (Group 1, n=22) and foveal-sparing ILM peeling (button-hole) (Group 2, n=20). Subgroup analyses were performed based on MH presence or absence detected preoperatively or intraoperatively. Results: Both groups showed significant improvement in BCVA, with Group 1 improving from 20 to 55 ETDRS letters and Group 2 from 25 to 65 ETDRS letters ( p <0.001). Postoperative BCVA was significantly better in Group 2 ( p =0.039). MH formation occurred in 22.7% eyes of Group 1 but not in Group 2 ( p =0.049). Subgroup analysis showed consistent benefits of the button-hole technique even after adjusting for baseline differences ( p =0.034). Conclusion: Foveal-sparing ILM peeling (button-hole) has superior visual and anatomical outcomes than conventional ILM peeling, reducing postoperative MH incidence in patients with RAM rupture.