Selective Laser Trabeculoplasty (SLT) for Glaucoma Treatment
Glaucoma is a condition where elevated intraocular pressure (IOP) damages the optic nerve and visual field, leading to irreversible vision loss. The most common type is open-angle glaucoma. Normally, aqueous humor (the fluid inside the eye) drains through trabecular meshwork channels. In glaucoma, these channels become blocked, causing an increase in eye pressure.
Since glaucoma is irreversible, early diagnosis and treatment are critical. Treatment focuses on reducing intraocular pressure by either:
✔ Decreasing aqueous humor production
✔ Enhancing fluid drainage
Traditionally, IOP-lowering eye drops have been the first-line treatment, but they have several disadvantages, including:
❌ High cost
❌ Daily use challenges
❌ Potential side effects
❌ Poor patient compliance
As an alternative, argon laser trabeculoplasty (ALT) was developed. However, it was not widely accepted because:
- It was not highly effective.
- The treated areas tended to close over time, reducing its long-term benefits.
In recent years, a newer laser technique, Selective Laser Trabeculoplasty (SLT), has been developed and approved by the U.S. FDA. SLT is now widely and safely used worldwide as an effective treatment for open-angle glaucoma.
How SLT Works
SLT reduces intraocular pressure by:
✔ Clearing blockages in the trabecular meshwork
✔ Enhancing the natural outflow of aqueous humor
Unlike previous laser treatments, SLT selectively targets only pigmented cells in the trabecular meshwork without affecting non-pigmented cells or connective tissue.
Why is this important?
🔹 Other laser treatments cause scarring, leading to the eventual closure of drainage channels.
🔹 SLT does not cause scarring, allowing the channels to remain open for a longer period.
🔹 This makes SLT more effective and longer-lasting than older laser techniques.
💡 In patients who previously failed ALT, SLT has shown success rates of over 50%.
Advantages of SLT
✔ Safe and highly selective (targets only pigmented cells, preserving other tissues)
✔ Long-lasting effects (less likelihood of drainage channels closing)
✔ Minimal side effects (temporary increase in IOP may occur but resolves quickly)
✔ Effective even in cases where ALT has failed
✔ No need for daily medications (avoids issues like side effects and compliance problems)
✔ Lower risk compared to surgical treatments
Conclusion
Selective Laser Trabeculoplasty (SLT) is a major advancement in glaucoma treatment. Its safety, selectivity, and long-term effectiveness make it a valuable alternative to both medications and surgery. By enhancing natural fluid drainage without scarring, SLT provides a safer, more effective, and sustainable solution for managing open-angle glaucoma.
