Understanding Keratoconus
Getting it Keratoconus
Keratoconus is a progressive eye disease that causes the cornea, which is usually round, to thicken and bulge into a cone shape. Because of this strange shape, vision gets distorted, glare, and light sensitivity. The goal of treatment is to stop the disease from worsening and bring back functional vision. Many surgical techniques have been created over the years, But none have the same potential for visual rehabilitation as specialty contact lenses, especially scleral lenses.
Here is a full look at modern and new surgical options, followed by a direct comparison to
speciality lenses.
Modern and Emerging Surgical Procedures in Keratoconus
1. Corneal Collagen Cross-Linking (CXL)
What it is:
CXL is designed to halt the progression of keratoconus by strengthening the collagen fibers in the cornea. This is done by applying riboflavin (vitamin B2) eye drops and activating them with ultraviolet (UV-A) light.
Benefits:
● Stabilizes corneal structure
● Prevents further steepening or thinning
Drawbacks:
● Does not improve vision—only stops progression.
● Many patients still need specialty lenses for visual clarity.
● Potential side effects: pain, corneal haze, and delayed epithelial healing.
2. Intracorneal Ring Segments (ICRS)
What it is:
To make the cornea flatter and less irregularly astigmatic, semi-circular plastic pieces like Intacs or Ferrara rings are put into it.
Benefits:
● Can improve corneal shape and reduce refractive error
● Minimally invasive procedure
Drawbacks:
● Unpredictable results; some patients see little to no improvement
● Possible complications: infection, ring extrusion, or glare
● Specialty lenses often still required for optimal vision
3. Topography-Guided PRK + CXL (Athens Protocol)
What it is:
A combination of topography-guided surface laser ablation (PRK) and CXL. It intends to change the form of the cornea and make it stronger all at once.
Benefits:
● Offers some improvement in vision and corneal regularity
● Stabilizes disease
Drawbacks:
● Effective mostly in mild to moderate cases
● Vision improvement is often modest
● May still require contact lenses afterward
● Risk of corneal haze and long-term unpredictability
4. Corneal Transplantation (PK and DALK)
What it is:
● Penetrating Keratoplasty (PK): Full-thickness corneal transplant
● Deep Anterior Lamellar Keratoplasty (DALK): Partial transplant that preserves the endothelium
Benefits:
● Used in advanced keratoconus or scarring
● Can significantly improve corneal clarity and thickness
Drawbacks:
● High surgical risk: rejection, infection, or graft failure
● Long recovery time (6–12 months)
● Often requires scleral or GP lenses post-surgery
● Lifelong follow-up and medications
5. Bowman Layer Transplantation (BLT)
What it is:
A thin donor In advanced keratoconus, Bowman’s membrane is put into the middle of the stroma to keep the cornea stable, especially when a corneal transplant has to wait.
Benefits:
● May delay full corneal transplantation
● Helps stabilize advanced keratoconus
Drawbacks:
● Does not improve vision
● Technically demanding procedure
● Patients still rely on specialty lenses afterward
6. Corneal Allogenic Intrastromal Ring Segments (CAIRS)
What it is:
Biological alternative to synthetic ICRS—uses donor corneal tissue to reshape the cornea.
Benefits:
● Better biocompatibility compared to PMMA-based ICRS
● Less risk of foreign body-related complications
Drawbacks:
● New technique, still under study
● Long-term safety and effectiveness unclear
● Often still requires lenses for vision correction
7. Small-Incision Lenticule Intrastromal Keratoplasty (sLIKE)
What it is:
A corneal lenticule (tissue disc) created during a SMILE procedure is implanted into a
keratoconic cornea to increase corneal thickness and potentially improve shape.
Benefits:
● Increases biomechanical strength and thickness
● May support visual and structural improvement
Drawbacks:
● Still experimental
● Limited clinical data available
● Long-term effects not known
● Does not eliminate the need for lenses
8. Implantable Collamer Lens (ICL)
What it is:
A phakic intraocular lens is implanted inside the eye to correct high myopia or astigmatism in
stable keratoconus.
Benefits:
● Corrects residual refractive error
● Useful in patients not suitable for corneal refractive surgery
Drawbacks:
● Does not treat corneal irregularity
● Only suitable if keratoconus is stable
● Risks include cataract, glaucoma, or dislocation
● Does not replace scleral lenses
Why Specialty Contact Lenses Especially Scleral Lenses Are Superior
Specialty contact lenses, such as scleral, hybrid, and custom soft lenses, are specifically designed to mask corneal irregularities and restore high-quality vision.
Scleral Lenses: The Gold Standard
Key Benefits:
● Vault the entire cornea, creating a new, smooth optical surface
● Provide exceptional vision, even in severe keratoconus
● Maintain a liquid reservoir over the cornea, promoting comfort and ocular surface healing
● Customizable for any corneal shape or post-surgical eye
● Non-invasive, reversible, and adjustable
Why Surgery Often Requires Lenses Anyway
Most surgical options—whether cross-linking, ring segments, or transplants—do not fully correct visual distortion caused by keratoconus. In almost all cases, patients still need scleral or other specialty lenses to achieve optimal vision after surgery.
| Treatment Option | Stops Progression | Improves Vision | Surgical Risk | Still Needs Lenses |
|---|---|---|---|---|
| Corneal Cross-Linking (CXL) | ✅ Yes | ❌ Minimal | Moderate | ✅ Yes |
| Intracorneal Ring Segments (ICRS) | ❌ No | ✅ Variable | Moderate | ✅ Often |
| Topo-guided PRK + CXL | ✅ Yes | ✅ Modest | Moderate | ✅ Often |
| Corneal Transplant (PK/DALK) | ✅ Yes | ✅ Major | High | ✅ Often |
| Bowman Layer Transplant (BLT) | ✅ Yes | ❌ No | High | ✅ Yes |
| CAIRS (Biologic Rings) | ❌ No | ✅ Early promise | Moderate | ✅ Often |
| sLIKE (Lenticule Implant) | ✅ Potentially | ✅ Experimental | High | ✅ Yes |
| ICL (Implantable Lens) | ❌ No | ✅ Refractive only | High | ✅ Yes |
| Scleral Lenses | ❌ No | ✅ ✅ Excellent | ❌ None | ✅ Primary Option |
Conclusion
While surgical techniques continue to evolve, none have consistently matched the visual rehabilitation, safety, and adaptability of specialty contact lenses, especially scleral lenses. They give you better vision without the risks of surgery, and they are still the most important part of treating keratoconus at all stages.
Specialty lenses are the best choice for most people with keratoconus, especially those who want clear, comfortable, and non-invasive vision correction.
About the Writer
Reekham Lal is an expert in specialty contact lenses who lives in Hyderabad, India. He makes custom scleral lenses for corneas that are hard to fit, like those with keratoconus, post-LASIK ectasia, or post-transplant eyes. He is also a PhD student who is studying how wearing scleral lenses changes the surface of the eye.
