What is the appropriate management for Laser-Induced Subepithelial Keratomileusis (LESI)?

Management of Laser-Induced Subepithelial Keratomileusis (LESI) Complications

For LESI complications, treatment should focus on epithelial healing with bandage contact lenses, topical antibiotics, and lubricants, while avoiding corticosteroids that could delay healing.

Understanding LESI

Laser-Induced Subepithelial Keratomileusis (LESI), also known as Laser Subepithelial Keratomileusis (LASEK), is a refractive surgery technique that combines elements of PRK and LASIK. The procedure involves:

• Creating an epithelial flap using dilute alcohol (typically 15-20% for 20 seconds)
• Reflecting the epithelium
• Performing excimer laser ablation
• Repositioning the epithelial flap
• Applying a bandage contact lens

Common Complications and Management

1. Epithelial Flap Complications

• Epithelial Flap Detachment

  • Apply a bandage contact lens immediately
  • Prescribe topical antibiotics (e.g., fluoroquinolones)
  • Add preservative-free lubricants
  • Monitor for 7-10 days until complete re-epithelialization 1
  • Avoid corticosteroids as they may delay epithelial healing

• Incomplete Epithelial Flap Removal

  • Occurs in approximately 12% of cases 2
  • If minor: observe with bandage contact lens
  • If significant: consider gentle debridement of loose epithelium

2. Diffuse Lamellar Keratitis (DLK)

• Presentation: Interface inflammation with granular reaction in the early postoperative period
• Management:
  • Increase frequency of topical corticosteroids for mild cases
  • For severe cases, consider flap lift and irrigation 3
  • Monitor closely as extensive DLK can lead to stromal loss and refractive changes

3. Central Toxic Keratopathy

• Presentation: Non-inflammatory central/pericentral amorphous corneal opacity
• Management:
  • Unlike DLK, steroids are generally NOT recommended
  • Invasive intervention is generally not recommended
  • Observe for residual thinning, striae, and hyperopia 3

4. Postoperative Infection

• Presentation: Pain, redness, photophobia, focal infiltrates
• Management:
  • Obtain corneal scrapings for microbiological investigation
  • Initiate intensive broad-spectrum topical antibiotics
  • If interface is involved, consider flap elevation for direct application of antibiotics
  • Severe cases may require flap amputation 3

5. Corneal Haze

• Prevention:
  • Consider mitomycin-C application for high-risk cases
• Management:
  • Topical corticosteroids for mild to moderate haze
  • For severe cases, consider phototherapeutic keratectomy (PTK)
  • RGP contact lenses for visual rehabilitation 3

6. Visual Aberrations and Irregular Astigmatism

• Management:
  • Trial with rigid gas permeable (RGP) contact lenses
  • Consider topography-guided ablation for significant irregularities
  • Scleral lenses for more severe cases 3

Follow-up Protocol

1. Day 1: Check epithelial flap position and integrity
2. Days 3-5: Remove bandage contact lens if epithelium is healed
3. Week 2: Assess for early complications (haze, DLK)
4. Month 1-3: Monitor for refractive stability
5. Month 6-12: Final assessment of outcomes

Special Considerations

• Thin Corneas: LESI may be preferred over LASIK as it conserves stromal tissue 4
• High-Risk Occupations: LESI may be safer for patients at risk of corneal trauma 4
• Retreatment Options: Surface ablation (PRK) is preferred over re-lifting the epithelial flap

Prevention of Complications

• Strict patient selection criteria
• Proper surgical technique with appropriate alcohol concentration and exposure time
• Adequate postoperative lubrication
• Early recognition and management of complications

By following these management principles, most LESI complications can be effectively addressed with good visual outcomes. The procedure offers advantages over both PRK and LASIK in selected cases, particularly for patients with thin corneas or those at higher risk of flap complications.