Purpose: This study investigated the relationship between forceps trauma during internal limiting membrane (ILM) peeling and its effects on focal and overall retinal nerve fibre layer (RNFL) loss and their impact on central visual fields following macular hole surgery. Methods: We conducted a post hoc analysis of ILM peeling surgeries for idiopathic full thickness macular hole collected previously as part of a prospective study. This included video analysis to assess the position of ILM pick-up points (PUPs), associated retinal hemorrhages, and the overall duration of ILM peeling. Subsequently, we correlated these findings with multimodal imaging as well as visual field data at 3 weeks and 6 months postoperatively. Results: The analysis encompassed a total of 43 eyes of 43 patients, with 213 PUPs performed by four experienced surgeons. The median peeling time was 263 seconds and the median number of PUPs per case was 5.6. PUPs were found to be associated with hemorrhages and subacute nerve fibre layer swelling (SANFL) lesions in approximately 20% of cases overall. Although PUPs, especially those linked with SANFL lesions and hemorrhages, were associated with focal RNFL defects, most defects were in the outer temporal sector of the macula and unrelated to PUPs. There were 192 focal RNFL defects observed but only 16% were associated with PUPs. PUPs in the inner and temporal sectors of the macula, and the severity of a DONFL appearance, demonstrated a significant correlation with peripapillary RNFL loss on multivariate analysis. No correlation between central visual field improvement and any of the anatomical changes was found. Conclusion: Whilst forceps trauma can result in SANFL lesions and focal RNFL loss, over 80% of focal RNFL defects observed after ILM peeling are not associated with PUPs and may be more associated with the act of ILM avulsion from the underlying retina during peeling. Keywords: ILM peeling, forceps, SANFL, DONFL, iatrogenic damage, peel maculopathy
Raimondi et al. (Sun,) studied this question.