Familial Limbal Stem Cell Deficiency: Clinical, Cytological and Genetic Characterization

Limbal stem cell diseases

The function of limbal stem/progenitor cells (LSCs) is critical to maintain corneal epithelial homeostasis. Many external insults and intrinsic defects can be deleterious to LSCs and their niche microenvironment, resulting in limbal stem cell dysfunction or deficiency (LSCD). Ocular comorbidities, frequent in eyes with LSCD, can exacerbate the dysfunction of residual LSCs, and limit the survival of transplanted LSCs. Clinical presentation and disease evolution vary among different etiologies of LSCD. New ocular imaging modalities and molecular markers are now available to standardize the diagnosis criteria and stage the severity of the disease. Medical therapies may be sufficient to reverse the disease if residual LSCs are present. A stepwise approach should be followed to optimize the ocular surface, eliminate the causative factors and treat comorbid conditions, before considering surgical interventions. Furthermore, surgical options are selected depending on the severity and laterality of the disease. The standardized diagnostic criteria to stage the disease is necessary to objectively evaluate and compare the efficacy of the emerging customized therapies.

Evaluation of limbal transplantation in eyes with bilateral severe ocular surface damage secondary to chemical injury

PURPOSE

To evaluate the outcome of limbal transplantation in eyes with bilateral severe ocular surface damage secondary to chemical injury.

PATIENTS AND METHODS

This was a retrospective case series that included 20 patients who had undergone living related limbal transplantation due to the presence of bilateral severe stem cell deficiency resulting from chemical injury. Medical records of the selected patients were reviewed. The following data were recorded and analyzed: gender; age at the time of the surgery; duration of follow-up; corrected distance visual acuity (CDVA); symptoms; intraocular pressure (IOP); any complications; postoperative treatment; and other surgical procedures needed.

RESULTS

The mean age of the included patients was 27.4±9.3 years. The causative agent was an alkali in 14 patients. Fifteen patients (75%) had a stable ocular surface (ie, complete corneal re-epithelization and resolution of postoperative inflammation) after the first limbal transplantation, while the other five patients (25%) needed regrafting. As regards the IOP; five patients (25%) needed Ahmed's valve implantation to control the IOP. Other surgical procedures needed were penetrating keratoplasty (PKP) in three patients (15%), cataract surgery in six patients (30%), and lid surgery in one patient (5%).

CONCLUSION

In conclusion, living related conjunctival limbal allograft transplantation, especially when combined with amniotic membrane transplantation, yielded good results in the management of cases with bilateral severe chemical eye injuries.