Keratoconus: five custom lens options
Five lens designs, from most to least specialised. Diagnosis, monitoring and cross-linking are covered in our keratoconus series.
- 01Keratoconus: five custom lens options
- 02High myopia: large-diameter lenticular RGP
- 03High astigmatism: rigid lenses only
- 04High hyperopia: why custom soft comes first
- 05Presbyopia: multifocals measured, not guessed
- 06Prosthetic lenses: appearance, comfort and vision
- 07Severe dry eye: scleral lenses for surface repair
When lenses take over from glasses
Part 01 · 01For patientsKeratoconus makes the cornea, the clear front window of the eye, thin and bulge into an irregular cone. Because the surface is irregular, glasses often can’t give clear vision. A specialty contact lens gives the eye a smooth new optical surface, and for most people it is the best way to restore sharp vision.
Glasses can’t reach 6/9
The irregular surface scatters light in a way glasses can’t correct.
The prescription is very high
Thick, strong glasses distort the edges of the view.
The two eyes differ a lot
Very different glasses make images different sizes, which the brain struggles to combine.
These lenses restore vision over the cone; they don’t treat it. Monitoring, eye-rubbing control and cross-linking carry on alongside.
Keratoconus series →Five options, most to least specialised
Part 01 · 02Scleral
Vaults the whole cornea and rests on the sclera. A fluid reservoir masks the irregular surface.Suits · moderate to advanced cones, RGP intolerance, scarring How scleral lenses are fitted →
Hybrid
Rigid centre for sharp optics, with a soft skirt for comfort.Suits · mild to moderate cones in comfort-driven patients
Corneal RGP
Small rigid lens. The tear lens beneath it creates a new optical surface.Suits · early to moderate cones; good oxygen and tear exchange
Limbal RGP
Intermediate diameter landing near the limbus. More stable than a corneal RGP without going scleral.Suits · decentred or larger cones
Custom soft
Thick, specially designed soft lens that masks mild irregularity.Suits · mild cones, or patients who can’t tolerate rigid lenses
Where each lens rests
Part 01 · 03The designs differ mainly in size and in where they bear weight: on the cornea, near the limbus, or out on the white of the eye.
Illustrative only: relative size and landing zone, not to scale.
How we choose between them
Part 01 · 04Who it suits
Stage and position of the cone, corneal shape, past lens history and lifestyle.
How it works on the cone
How the lens masks the irregularity, and where it bears or vaults.
Pros and cons
Vision, comfort, handling, oxygen and long-term corneal health.
What fitting involves
Topography-guided design, diagnostic lenses on the eye, and more than one visit to refine fit and power.
Key takeaways
Part 01- 01Specialty lenses give an irregular cornea a smooth new optical surface
- 02Five designs, from scleral to custom soft, chosen by cone and comfort
- 03Lenses restore vision; monitoring and cross-linking carry on alongside
Book a contact lens assessment.
Optometrists and ophthalmologists can refer through our referral form.
General health information only, not personal advice. Everyone’s eyes are different. An optometrist or doctor should examine you before any treatment is decided.