- Keratoconus is an eye condition in which the normally round dome-shaped clear window of the eye (cornea) progressively thins causing a cone-shaped bulge to develop.
- Keratoconus is an eye condition in which the normally round dome-shaped clear window of the eye (cornea) progressively thins causing a cone-shaped bulge to develop. The condition normally develops during your teens or twenties, and often gets worse gradually over time. The speed of change and severity varies between affected people.
Keratoconus and vision
The change in shape and thinning of the cornea impairs the ability of the eye to focus properly, causing poor vision. In advanced cases, some patients may develop scarring in the cornea, which can make the sight blurred by reducing the amount of light which can enter the eye.
In the early stages, spectacles or soft contact lenses may adequately correct vision. As the cornea becomes thinner and steeper, rigid gas permeable (RGP) contact lenses are often required to correct vision. In very advanced cases, where contact lenses fail to improve vision, a corneal transplant may be needed.
Corneal collagen crosslinking
Corneal cross-linking (also known as CXL) is a new treatment that can stop keratoconus getting worse. Also known as C3R, it uses ultraviolet light and vitamin B2 (riboflavin) drops to stiffen (and strengthen) the cornea to prevent further steepening and thinning in the future. It is effective in over 90% of patients.
Usually by your late 30s, the cornea naturally stiffens and CXL is generally not required. Below this age, the cornea is more flexible and disease progression (and worsening vision) are more likely to occur.
Intracorneal stromal ring implants (ICRS) are placed in a laser-formed channel within the cornea. Depending on the severity of the keratoconus, one or two rings are implanted with the aim of improving the overall shape of the cornea (reducing astigmatism and irregularity). Corneal ring implants can be combined with, or precede, corneal cross-linking.
Phakic intra-ocular lens implant
Lens implants within the eye may be suitable in keratoconus patients with good vision in spectacles or soft contact lenses. Lens implants are generally not effective in correcting vision in patient’s dependent on rigid gas permeable contact lenses (RGP). Depending on the prescription, patients may benefit from lens implants in one or both eyes.
Transepithelial phototherapeutic keratectomy (TransPTK)
TransPTK is a laser treatment designed to flatten and smooth the surface of the cornea. The aim of the treatment is to improve the focusing of the cornea, with sharper vision in either spectacles or contact lenses. TransPTK can be combined with cross-linking during the same procedure.