Perspektiven und aktueller Stand der Limbusstammzelltransplantation

[Surgical management of firework-induced eyelid injuries]

Fireworks injuries are frequently caused by malfunction or incorrect operation of fireworks. Injuries often affect the eyeball and the periorbit. After treatment of life-threatening bleeding, injuries of the eyeball have priority over the treatment of periorbital lacerations and burns. The aim of eyelid surgery in firework-related injuries is to prevent delayed damage, such as lagophthalmos, symblepharon, entropion with trichiasis, and keratinization of the conjunctiva of the eyelid and eyelid margin. The treatment requires a considerable amount of time and patience both for the elaborate surgical procedures as well as for the necessary healing and rest phases. Many patients, however, are left with serious visual impairments and stressful esthetic deformities, which result in considerable occupational and social impairments.

Long-term results of allogenic penetrating limbo-keratoplasty: 20 years of experience

AimThe objective of the study was to evaluate the long-term results of allogenic penetrating limbo-keratoplasy. This method allows simultaneous transplantation of a corneal graft and limbal stem cells of the donor by means of eccentric trephination of the donor button.MethodThe data of 192 consecutive cases of allogenic penetrating limbo-keratoplasty from 1995 to 2015 were reviewed. These had been performed exclusively in eyes with complete failure of the limbal stem cells, in combination with deep corneal scarring. Indications were predominantly eye burns, inflammatory conditions, and congenital aniridia. Graft survival and rejection rates were assessed using Kaplan-Meier analysis.ResultsFollow-up averaged 2.1±2.2 years. Median graft survival was 3.4 years in eye burns, 3.9 years in inflammatory disease, and 3.2 years in congenital aniridia. Median survival was 3.9 years in the heterogenous group of other indications.ConclusionAllogenic limbo-keratoplasty is a suitable option used to treat patients with bilateral complete failure of the limbal stem cells and deep opacification of the central cornea. The main reasons for graft failure are the loss of graft-limbal stem cell functioning and endothelial graft rejection.

Cell-based therapies for ocular inflammation

Since the plasticity and the potential for re-programming cells has become widely accepted, there has been great interest in cell-based therapies. These are being applied to a range of diseases, not least ocular diseases, where it is assumed that there is a reduced risk of immune rejection although this may be more perceived than real. There are two broad classes of cell-based therapies: those aimed at restoring structure and function of specific tissues and cells; and those directed towards restoring immunological homeostasis by controlling the damaging effects of inflammatory disease. Stem cells of all types represent the first group and prototypically have been used with the aim of regenerating failing cells. In contrast, immune cells have been suggested as potential modulators of inflammation. However, there is functional overlap in these two applications, with some types of stem cells, such as mesenchymal stem cells, demonstrating a potent immunomodulatory effect. This review summarises recent information on cell based therapies for ocular disease, with special emphasis on ocular inflammatory disease, and explores current uses, potential and limitations.

[Ocular surface reconstruction in limbal stem cell insufficiency: transplantation of limbal tissue]

Reconstruction of the ocular surface in patients with limbal stem cell insufficiency (LSI) remains one of the most challenging tasks in ophthalmology. The transplantation of lamellar limbal tissue in total LSI represents an established therapeutic concept, while an abrasion of the conjunctival pannus allowing normal limbal epithelium to recolonize the cornea is the treatment of choice in partial LSI. Surgery must be postponed until an inflammation-free period is reached and lid abnormalities have been corrected. In unilateral total LSI autologous limbal tissue from the healthy eye is transplanted in order to circumvent immunological adverse events. In bilateral total LSI cadaveric or living related allogenic limbal tissue is used for transplantation, in which case systemic immunosuppression and HLA matching are mandatory. The combination with amniotic membrane transplantation and mitomycin C treatment can further improve long-term outcome of limbal stem cell transplantation.