Treatment of Limbal Stem Cell Deficiency
The treatment of limbal stem cell deficiency (LSCD) should begin with amniotic membrane transplantation for partial LSCD cases, while severe or total LSCD requires limbal stem cell transplantation with appropriate immunosuppression when indicated. 1
Classification and Diagnosis
LSCD can be classified as:
- Partial LSCD: Affects only portions of the limbus
- Total LSCD: Involves the entire limbal circumference
- Unilateral vs. Bilateral: Determines source of donor tissue
Diagnostic features include:
- Invasion of conjunctival epithelium onto corneal surface
- Corneal neovascularization
- Persistent epithelial defects
- Corneal scarring and opacification
Treatment Algorithm
1. For Partial LSCD:
First-line treatment: Amniotic membrane transplantation (AMT)
- Success rate: Stable corneal epithelium in most cases
- Re-epithelialization time: Approximately 23 days
- Visual improvement in >90% of cases with visual potential 2
- Reduces pain, photophobia, vascularization, and inflammation
Conservative management for mild cases (especially contact lens-related):
- Discontinuation of contact lens wear
- Aggressive lubrication with preservative-free artificial tears
- Topical anti-inflammatory agents (corticosteroids for short-term use)
- Topical cyclosporine 0.05% for longer-term management 1
2. For Total LSCD:
Autologous limbal stem cell transplantation (for unilateral cases):
- Conjunctival limbal autograft (CLAU)
- Simple limbal epithelial transplantation (SLET)
Allogeneic limbal stem cell transplantation (for bilateral cases):
- Requires systemic immunosuppression
- Should be performed by specialists experienced in ocular surface stem cell transplantation 3
Cultivated cell-based approaches:
- Cultivated limbal epithelial transplantation (CLET)
- Cultivated oral mucosal epithelial transplantation (COMET)
- Viable alternative for bilateral LSCD
- Kaplan-Meier analysis shows 64.8% stability at 1 year, 59.0% at 2 years, and 53.1% at 3 years 4
3. For Advanced Cases with Corneal Opacity:
- Keratoprosthesis may be considered when:
- Previous transplants have failed
- Severe bilateral visual impairment exists
- Retention rate: 90-92% at 1 year, 80-87% at 2 years 1
- Visual acuity improves to 20/200 or better in 50-89% of patients at 1 year
Etiology-Specific Considerations
Contact Lens-Related LSCD:
- Typically presents as focal LSCD, predominantly affecting superior limbus
- 61.1% of cases resolve with cessation of contact lens wear and artificial tears
- Some cases require topical corticosteroids or surgical intervention 5
Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis:
- Early intervention is critical to prevent late complications
- Early amniotic membrane transplantation is highly recommended for ocular surface and eyelid margin 1
Ocular Mucous Membrane Pemphigoid:
- Requires systemic immunosuppression
- Surgical reconstruction carries high risk 1
Graft-versus-Host Disease:
- Aggressive lubrication and punctal occlusion
- Topical corticosteroids for conjunctival hyperemia and scarring
- Topical cyclosporine and autologous serum tears 1
Complications and Management
- Persistent epithelial defects: Associated with early failure of transplantation
- Corneal melting/perforation: More common with persistent epithelial defects
- Infectious keratitis: Requires prompt antimicrobial therapy
- Glaucoma: Common complication requiring close monitoring
- Recurrence of underlying disease: May necessitate repeat procedures
Important Considerations
- Patient selection is crucial for successful outcomes
- Systemic immunosuppression should not be feared but managed in collaboration with organ transplant specialists 3
- Long-term follow-up is essential to monitor for complications and recurrence
- Early intervention generally leads to better outcomes than delayed treatment
Pitfalls to Avoid
- Performing penetrating keratoplasty without addressing LSCD first - This approach is likely to fail
- Underestimating the need for systemic immunosuppression in allogeneic transplantation
- Delaying treatment in cases of chemical/thermal injuries or Stevens-Johnson syndrome
- Failing to monitor for glaucoma, which is a common complication after keratoprosthesis
The management of LSCD has evolved significantly, but remains challenging and requires specialized expertise. Regional centers with experienced corneal surgeons should be developed to make these treatments more accessible to patients with this vision-threatening condition 3.