Amniotic Membrane in Excimer Laser Surface Ablation (ELSA): Mechanisms for Haze Prevention and Broader Ocular Surface Optimisation

Abstract

Subepithelial corneal haze remains a clinical risk after excimer laser-based surface ablation (ELSA), especially with deep ablations, high myopia or retreatments, with downstream effects on vision and quality of life. Mitomycin C (MMC) is widely used intraoperatively for haze prophylaxis and has multi-study support; however, its antiproliferative, anti-fibrotic action does not directly address early inflammation, epithelial barrier restoration or neuroregeneration, and use remains off-label with heterogeneous protocols. This narrative review synthesises preclinical, early clinical (non-randomised/small trials) and established clinical evidence (randomised trials/systematic reviews or guidelines) on amniotic membrane transplantation (AMT) as a complementary adjunct in ELSA. We emphasise modern, sutureless, dehydrated AMT (dAM), including vision-preserving formats suited to peri-operative workflows. Across adjacent ocular-surface indications, AMT demonstrates multi-modal properties: anti-inflammatory/immunomodulatory, antioxidant, anti-proteinase (including matrix metalloproteinase-9 suppression) and support of epithelial and nerve recovery. In ELSA-specific work, preclinical photorefractive keratectomy (PRK) models show reduced haze and faster epithelialisation with patch-AMT; one prospective laser-assisted sub-epithelial keratectomy (LASEK) human study reports faster healing and lower opacity versus standard care. By contrast, small fellow-eye studies using ring-mounted cryopreserved-AMT devices showed no superiority for routine myopic PRK, underscoring the importance of format and protocol. This review outlines a complementary paradigm: MMC targets downstream fibrosis, whilst patch-AMT acts earlier on inflammation, epithelial repair, protease imbalance (including MMP-9) and neurotrophic support. With major international guidelines now recognising sutureless patch-AMT for regeneration and inflammation/oxidative stress control in dry eye, prospective refractive-cohort trials with standardised product/placement protocols, long-term follow-up, patient-reported outcomes and embedded health-economic evaluation are warranted to define AMT’s role alongside MMC in routine ELSA.