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Ocular surface reconstruction with autologous mucosal membrane transplantation in limbal stem cell deficiency Elisabeth Macdonald Suzannah Drummond Kanna Ramaesh Authors have no financial interest Background Corneal limbal stem cell deficiency (LSCD) causes corneal opacification and blindness Repopulation with stem cells may occur by transplanting limbal tissue from a donor source or with ex vivo expanded LSC Cultured oral mucosal epithelial cells have previously been used as an alternative to limbal transplantation An Alternative ? Mucous Membrane Epithelium Reports of cultured autologous oral mucosal epithelium for LSCD: Nakamura et al. Transplantation of cultivated autologous oral mucosal epithelial cells in patients with severe ocular surface disorders BJO 2004;88:1280-84 Tsutomu et al. Midterm results on ocular surface reconstruction using cultivated autologous oral mucosal epithelial transplantation Am J Ophth 2006;141:267 Can the method be simplified by avoiding the cultivation step ? Is direct migration from perilimbal mucous membrane grafts (MMG) possible ? Why Mucous Membrane? Autograft material Readily available Widely used historically to replace abnormal conjunctiva 1st use 1876 by Klein Denig: Textbook of Surgery 1943 Epithelium similar to corneal epithelium Purpose and Methods We describe a novel surgical technique of direct oral MMG to rehabilitate LSCD Direct oral MMG has not been previously reported to restore corneal transparency The results of 5 patients are report LSCD was characterised by conjunctivalisation of the corneal surface, corneal scarring, recurrent epithelial defects and corneal vascularisation and later confirmed by immunohistochemistry No donor site complications occurred Surgical technique A 360 peritomy and removal of abnormal epithelium and fibrovascular tissue covering the cornea were performed A small strip of buccal oral mucosa was excised and the sub-stromal adipose tissue removed The mucosal membrane strips were sutured to the exposed perilimbal sclera Results Baring of the corneal stroma allowed migration of mucous membrane epithelium Pre Op Post Op This produced transparent epithelium on the cornea in 4 cases In one case radial corneal vessels invaded from the periphery Cases Transparent epithelium on cornea Age Co Previous ocular morbidity reconstruction surgery 37 Chemical AMG Injury 52 OCP 2 x failed stem cell grafts, DLK Pre Op BCVA HM Post Op Co Pathology BCVA 2yrs 3/60 CF 6/60 52 OCP None CF 6/36 61 Aniridia Lamellar corneal HM graft 6/24 70 OCP Conjunctival autograft 6/12 6/36 CRVO Macula hypoplasia, Optic neuropathy Epithelial cell maintenance The mucosal epithelial cells migrated from the MMG in the perilimbal region onto the cornea to provide a stable corneal surface On slit lamp examination the migrated epithelium appeared very similar to normal corneal epithelium and was transparent The epithelium over the cornea has been maintained and has behaved like ‘corneal epithelium’ The Hypothesis Mucous membrane grafts Success of ex vivo expanded oral mucosal epithelial transplantation is attributed to the presence of stem cells among the transplanted population Progenitor cells These are derived from resident stem cells of the oral mucosa epithelium It is our belief that the success of the technique is due to the survival of the stem cells within the transplanted oral mucosa to the vascular perilimbal location These cells may act as a reservoir and generate a progeny of differentiated epithelial cells that cover the cornea Direct MMG compared with reported cultivated epithelial technique Duration of our results is the same or longer Perilimbal vascular invasion similar Advantages of our technique: Much less expensive No need for laboratory No risk of transmitted disease Conclusion New finding Mucosal epithelium migrates from perilimbal grafts to produce functional corneal epithelium Simple and cheap technique Direct autologous perilimbal transplantation of oral mucosal tissue may be an alternative to limbal stem cell transplantation to reconstruct the corneal surface and restore vision in selected cases of severe LSCD