Retained Host Descemet Membrane (Auto-DMET) During Conversion of Deep Anterior Lamellar Keratoplasty to Penetrating Keratoplasty: A Case Report

Purpose: The aim of this study was to relate a case of deep anterior lamellar keratoplasty (DALK) converted to penetrating keratoplasty in which the host central Descemet membrane (DM) with a large perforation was left attached to the host cornea. Methods: This is a case report of a 34-year-old man who underwent an attempted DALK for keratoconus in his left eye, which became complicated with a large rupture in DM during dissection. The host DM was left in place, the donor cornea with DM intact was sutured onto the host bed, and air was injected into the anterior chamber. The patient was monitored by biomicroscopy, pachymetry, topography, anterior segment optical coherence tomography, and specular microscopy. Results: The postoperative course resulted in improved uncorrected visual acuity, best spectacle-corrected visual acuity, and topography. Corneal edema was observed in the host cornea peripheral to the graft. Three months after the surgery, the endothelial cell density was reduced by 63% compared with the preoperative donor cell density. Conclusions: Leaving the host DM during conversion of DALK to penetrating keratoplasty was uneventful in this case, although corneal edema was observed in the area overlying the host cornea. It is possible that the retained DM could provide additional autologous endothelial cells to prolong graft survival.