When the cornea becomes a cone.
In keratoconus the clear front window of the eye thins and bulges forward. Its surface turns irregular, so light no longer focuses to one point. Glasses help less over time. The right lens can restore a smooth surface.
Read the in-depth series →- Usually starts
- Teens to twenties
- Early signs
- Blur, ghosting, frequent changes to glasses
- Monitored by
- Corneal topography, repeated over time
- Treated with
- Rigid, hybrid or scleral lenses; cross-linking if it progresses
Who it helps
Newly diagnosed
Understand what is happening to the cornea, and what to watch for.
When glasses stop working
Vision that stays smeared or doubled, even with a new prescription.
After cross-linking or a graft
The cornea is stable but still irregular. A lens restores the optics.
What happens to the cornea
Side view, five stepsA regular cornea.
Cone and thinning exaggerated for clarity. Not to scale. How scleral lenses are fitted →
What the assessment involves
Sequence / 04History
Your symptoms, eye rubbing, allergies and family history.
Topography
A map of the cornea, compared with any earlier scans you bring.
Progression
Is the cone changing? If so, we refer you for cross-linking. Teenagers are referred at diagnosis.
Lens fitting
A rigid, hybrid or scleral lens, chosen for the shape of your cone.
Want the detail? Read the full keratoconus series
In depth · 06 partsSix short, illustrated parts on what causes keratoconus, how we track it, and each step from controlling it to restoring clear vision.
Why does the cornea become a cone?
A weaker cornea, an inherited tendency, and the forces that push it out of shape.
Read →Part 02Is my keratoconus getting worse?
Four measurements compared visit to visit, and when not to wait.
Read →Part 03Stop the rub: controlling what drives it
Rubbing, allergy and lid disease, plus three don’ts for blepharitis.
Read →Part 04Getting clear vision back
Glasses first, then five custom contact lens options.
Read →Part 05Cross-linking: stopping the cone getting worse
How it works, who it’s for, and what recovery looks like.
Read →Part 06Surgical options for selected cases
Ring segments, laser, implanted lenses and transplants.
Read →