Keratoconus is a non-inflammatory eye condition in which the normally round dome-shaped clear window of the eye (cornea) progressively thins causing a cone-like bulge to develop. This eventually impairs the ability of the eye to focus properly, potentially causing poor vision.
Covid-19 - Update on patient appointments
Due to the pandemic, we had to defer patient appointments in the Keratoconus clinic and other services at Moorfields. In order to safely and promptly see all of our patients when clinics are allowed to reopen, we have made some changes to the way that you will be monitored.
If you are already a patient with us, at your next appointment, you will have your corneal shape (topography) scans and a check of your vision. Although you will not get your results on the day, one of the specialist Optometrists will review your results within a few days and will be in touch. If your scans are stable, you will receive a letter confirming this. If not, you will be called. Please make sure that your contact details, including phone number, are up to date when you check in for your appointment at either at the desk or kiosk. Your appointment may not be at your usual hospital site, for example St. George’s hospital patients may be asked to come to Moorfields at City Road.
If you are a new patient, your first appointment will be with a clinician as usual. It is important that we see you in person at your first visit to confirm the diagnosis and establish a valid “baseline” set of measurements. Your appointment may not be at your usual hospital site, for example St. George’s hospital patients may be asked to come to Moorfields at City Road.
Visit our Frequently Asked Questions (FAQs) section for more help and advice on managing your condition at home.
You can find out more about the safety measures in place at Moorfields by visiting the Coronavirus section of our website, which includes guidance on the use of face coverings and surgical face masks.
What causes keratoconus and who gets it?
The exact cause is unknown. It is believed that genetics and environmental factors play a role. It is not generally considered an inherited disease, although rarely in some families more than one individual can be affected.
Depending on ethnicity, keratoconus affects up to one in 450 people. It is more common in non-caucasians. It is usually diagnosed in young people at puberty, in their late teens or early twenties.
How keratoconus affects vision
Early stages of keratoconus are detectable by your local optometrist. Vision is often unaffected in the very early stages. It is important to remember that keratoconus does not cause blindness. If left unchecked, further changes in shape, thinning of the cornea and, in advanced stages, scarring cause loss of transparency of the cornea which impairs the ability of the eye to focus properly. Even in advanced keratoconus however it is usually possible to correct vision with contact lenses.
Treatments for keratoconus
In the early stages, spectacles or soft contact lenses may be used to correct vision. As the cornea becomes thinner and steeper, soft or rigid gas permeable (RGP) contact lenses are often required to correct vision more adequately. In very advanced cases, where contact lenses fail to improve vision, a corneal transplant may be needed. This type of intervention is rare however since the introduction of corneal cross-linking (CXL). CXL is a relatively new treatment that can stop the disease getting worse. It is effective in over 94% of patients with a single 30 minute outpatient procedure.
What happens if I am referred for this condition?
Keratoconus does not require urgent referral since changes caused by the condition usually take several months or even years to develop. Because of this, we monitor those with the condition and invite them back for repeat assessments for up to five years from their initial visit.
Each time you attend this clinic, we will perform many of the same tests, including:
1. Vision (reading chart)
2. Refraction (spectacle test)
3. Corneal scans (including Pentacam)
We will compare these results with those from your previous visits. If any of the results show deterioration, we will discuss with you whether CXL is required.
CXL is only suitable where the corneal shape is continuing to deteriorate. This will be detected at your appointments. Beyond a certain stage however, if the cornea is too thin, it could be unsafe to perform the procedure. Usually in people in their 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, although not certain, to occur.
Leading your care
Mr Daniel Gore MD FRCOphth CertLRS
Lead clinician for Early Keratoconus & Corneal Cross-Linking Service
Marcello Leucci BSc (Hons)
Principal Optometrist, Keratoconus Monitoring Service
Moorfields Eye Hospital NHS Foundation Trust