A beginner's guide to mucous membrane grafting for lid margin keratinization: Review of indications, surgical technique and clinical outcomes.

The posterior lid margin, where the mucocutaneous junction (MCJ) between the eyelid skin and tarsal conjunctiva is located, plays a critical role in maintaining the homeostasis of the ocular surface. Posterior migration of the MCJ leads to lid-margin keratinization (LMK), which has a domino effect on the delicate balance of the ocular surface microenvironment. This occurs most commonly following Stevens-Johnson syndrome/toxic epidermal necrolysis and is not known to regress spontaneously or with medical therapy. Over time, LMK causes blink-related chronic inflammatory damage to the corneal surface which may have blinding consequences. Lid-margin mucous membrane grafting (MMG) is the only definitive therapy for LMK. Timely MMG can significantly alter the natural course of the disease and not only preserve but even improve vision in affected eyes. Literature searches were conducted on PubMed, using the keywords "mucous membrane grafts," "lid margin keratinization," "Stevens-Johnson syndrome," "toxic epidermal necrolysis," "lid related keratopathy," and "lid wiper epitheliopathy". This review, which is a blend of evidence and experience, attempts to describe the indications, timing, surgical technique, postoperative regimen, and clinical outcomes of MMG for LMK. The review also covers the possible complications and pearls on how they can be effectively managed, including how suboptimal cosmetic outcomes can be avoided. The authors hope that this review will aid ophthalmologists, including cornea and oculoplasty specialists, to learn and perform this vision-saving surgery better, with the aim of helping their patients with chronic ocular surface disorders, relieving their suffering, and improving their quality of life.