Retinal Microvascular Effects of Internal Limiting Membrane Peeling: A Meta-Analysis

Internal limiting membrane (ILM) peeling is widely used to relieve tangential traction and improve anatomical closure. As the ILM is continuous with Müller cells enstheathing retinal capillaries, peeling may impact the retinal microvasculature. We evaluated whether peeling impacts retinal vessel density as measured by optical coherence tomography angiography.

A systematic search of PubMed, Scopus, and Cochrane CENTRAL was conducted. Eligible studies included adult patients undergoing vitrectomy with ILM peeling and reported OCT-A vessel densities. Weighted mean differences were calculated for superficial (SCP) and deep capillary plexus (DCP) vessel density (VD) in the parafoveal and perifoveal regions.

Ten studies including 260 participants were analyzed for parafoveal outcomes, and five studies including 150 participants for perifoveal outcomes. ILM peeling was not associated with significant changes in any of the examined regions: parafoveal SCP VD (WMD = -0.53%; -1.43 to 0.38; p = .25), parafoveal DCP VD (WMD = 0.92%; -0.41 to 2.24; p = .17), perifoveal SCP VD (WMD = -1.10%; -2.80 to 0.61; p = .21), or perifoveal DCP VD (WMD = 1.37%; -1.39 to 4.14; p = .33). Meta-regression analyses did not identify significant effects.

ILM peeling does not appear to induce sustained microvascular loss detectable by OCT-A. Any early postoperative changes seem transient and should be interpreted cautiously. From a microvascular perspective, the findings support the safety of ILM peeling. Larger longitudinal studies using standardized OCT-A protocols are needed to confirm these findings and clarify any early VD fluctuations.