Case Report: Simultaneous penetrating keratoplasty with autologous simple limbal epithelial transplantation as an alternative to keratoprosthesis

Abstract

Introduction and importance: This case report highlights the multidisciplinary approach required to achieve successful anatomical and functional outcomes, in an eye with total limbal stem cell deficiency (LSCD) associated with underlying corneal scarring and thinning. Presentation of case: A 59-year-old gentleman had poor visual recovery in the right eye (RE) following accidental carbide blast, 1-year before presenting to us. The visual acuity was counting fingers and clinical examination revealed cicatricial entropion involving the upper eyelid, total LSCD, corneal scarring with a central descemetocele and cataract in the RE. Prior to ocular surface reconstruction, entropion correction was performed. Three months later, penetrating keratoplasty combined with cataract surgery and intraocular lens implantation (penetrating keratoplasty (PK) triple), with autologous simple limbal epithelial transplantation (SLET) was performed. The visual acuity was 20/100, 18 months after the surgery, with a clear well-epithelized corneal graft and stable ocular surface. Discussion: LSCD is caused by a decrease in the population and /or function of the limbal epithelial stem cells. Limbal stem cell transplantation (LSCT) is warranted in eyes with total LSCD. In eyes with coexisting corneal scarring, LSCT alone may be inadequate to restore the vision. These eyes require simultaneous or sequential lamellar or full-thickness corneal transplantation for visual rehabilitation. Though, the existing literature favors a sequential approach, where LSCT is performed first followed by corneal transplantation, under certain circumstances such as a thin underlying cornea like in our case, corneal transplantation may have to be combined with LSCT to achieve optimal outcomes. Conclusion: Combining autologous SLET with PK can be performed for visual rehabilitation in eyes with unilateral total LSCD and underlying corneal thinning. Corneal and limbal graft survival is prolonged if existing adnexal comorbidities are addressed before any surgical intervention is planned and adequate time interval is allowed for the surface inflammation to subside.

Keywords: cicatricial entropion; descemetocele; limbal stem cell deficiency (LSCD); limbal stem cell transplantation (LSCT); ocular burn; penetrating keratoplasty.

Figure 1.. External photograph of the right eye at presentation, shows cicatricial entropion involving the upper eyelid (yellow arrows, A). Slit-lamp image shows diffuse conjunctival hyperemia, pseudopterygium involving two clock hours of the nasal limbus and five clock hours of the temporal limbus with peripheral corneal vascularization involving all quadrants and central descemetocele measuring 3×4 mm (B). Corresponding anterior-segment optical coherence tomography (AS-OCT) image shows dense corneal scarring and severe thinning, with a residual thickness of 94 microns in the area of the descemetocele (C). Three months postoperative image, after entropion correction showing well integrated lid margin mucous membrane graft along the upper eyelid margin (yellow doted lines, D). 18 months postoperative slit-lamp image, after combined autologous simple limbal epithelial transplantation, penetrating keratoplasty triple procedure, showing a well epithelized corneal surface with a clear corneal graft (E). Corresponding AS-OCT image of the same visit, showing compact cornea and corneal epithelium noted over the entire cornea (F).