World Keratoconus Day 2026: Early Signs, Risk Factors and Modern Treatment
Today, 10 November, is World Keratoconus Day. Keratoconus is an eye condition in which the cornea, the clear window at the front of the eye, slowly thins and bulges into a cone shape,causing blurred, distorted vision that glasses can struggle to fix. It usually starts in the teenage years, but is often not diagnosed until the twenties orlater1,2,3. The good news is that earlier diagnosis and modern treatment mean most people keep good everyday vision, and keratoconus does not usually lead to blindness4.
How common is it?
Estimates vary. A large analysis of29 studies suggested about 1 in 725 people5,while more recent studies report higher figures, for example about 1 in 375 in the Netherlands3 and about 2% in parts of Latin America and the Caribbean1.The authors of a Cochrane review suggest the higher modern figures probably reflect better detection with corneal scans6.In short, it is not common, but it is far from unheard of, and it is often found late.
Early signs worth acting on
• Glasses prescriptions that keep changing, especially increasing short-sightedness or astigmatism.
• Blurred or distorted vision, or "ghosting" (faint double images), that does not clear with new glasses.
• Glare and sensitivity to light, particularly at night.
• One eye noticeably worse than the other. Keratoconus usually affects both eyes, but not usually equally4,7.
Early keratoconus can be missed in a routine sight test. A corneal scan (topography or tomography) maps the shape of the cornea and is the key test, so if you are concerned, ask your optician fora scan or a referral4. For children, the 2026 Global Consensus (an international expert agreement)recommends scans for anyone aged 6 to 18 with more than 2 dioptres of astigmatism on their glasses prescription7.
What raises the risk?
These are links, not proof of cause. Experts agreed that eye rubbing, a family history of keratoconus, allergic eye disease and atopy (a tendency towards allergies such as eczema or hay fever)are recognised risk factors7.Combined analyses link eye rubbing to roughly three to six times higher odds of keratoconus, and a family history to several times higher odds5,8. Not everyone who rubs their eyes will develop it, but regular rubbing is worth avoiding and itchy, allergic eyes deserve proper treatment. If a parent or sibling has keratoconus, tell your optician and have your corneas checked.
How is it treated?
• Glasses and contact lenses.Early on, glasses may be enough. Later, firm (rigid gas-permeable) or scleral lenses often give much sharper vision. They improve vision while worn but do not stop the condition getting worse4,7.
• Corneal cross-linking.Vitamin B2 drops and ultraviolet light are used to stiffen the cornea. Experts were unanimous that it should be done when scans show keratoconus is getting worse, and at least 86% supported considering it at diagnosis in under-18s,because it can progress faster in young people7.It aims to stop keratoconus getting worse rather than improve vision. NHS patient information says it halts progression in more than 9 in 10 treated eyes, and quotes about 3 in 100 patients with reduced vision in the treated eye9. The most widely used method removes the thin surface layer of the cornea ("epithelium-off")7. Methods that leave the surface in place may be more comfortable and also halt progression, but the evidence comparing the two is of low certainty and the expert panel did not regard them as the usual first choice6,7,10,.
• Implants. Corneal ring segments (tiny curved implants) can improve shape and vision in selected eyes11, but most experts agree they do not stop keratoconus getting worse7.
• Corneal transplant. Needed by a minority of people, usually when vision cannot be corrected well enough or contact lenses cannot be tolerated7,4.Most people with keratoconus will not need one4.
When it is an emergency
Rarely, advanced keratoconus can cause corneal hydrops, where fluid seeps into the cornea. It causes a sudden,painful clouding of vision and needs same-day assessment at an eye casualtydepartment4,12.
Why this year matters
In 2026 the Global Consensus on Keratoconus and Ectatic Diseases was updated ten years after the first edition,involving 128 participants from 12 international societies. It reflects expert agreement rather than evidence from randomised trials7. The message is clear: find it early,monitor it properly, and treat it promptly if it is getting worse.
What you can do this week
• Book a sight test if your vision is changing, and ask whether a corneal scan is appropriate.
• Try not to rub your eyes, and ask your optician or GP about itchy, allergic eyes.
• Mention any family history of keratoconus.
• If you already have keratoconus, keep every monitoring appointment. It can get worse without you noticing.
• Seek urgent care for sudden clouding of vision with pain.
Mr Mrinal Rana is a consultant corneal, cataract and refractive surgeon at University Hospitals Coventry and Warwickshire (UHCW), and sees private patients through Keratovision Limited at The Meriden Hospital in Coventry and in London. If you would like a specialist assessment, you can contact the Keratovision team.
This article is for general information and awareness. It is not a substitute for a personal clinical assessment. Outcomes vary between individuals, and no treatment carries a guarantee. If you have a sudden change in vision, eye pain or redness, seek urgent medical advice.
References
[1] Ekemiri K, Ekemiri C, Singh D, etal. Prevalence and Associated Factors of Keratoconus in Latin America and the Caribbean: A Systematic Review and Meta-Analysis. Vision (Basel). 2026;10(3). 10.3390/vision10030049
[2] Sheffield Children's NHS Foundation Trust. Keratoconus. Patient resource library. https://library.sheffieldchildrens.nhs.uk/keratoconus/
[3] Godefrooij DA, de Wit GA,Uiterwaal CS, Imhof SM, Wisse RP. Age-specific Incidence and Prevalence of Keratoconus: A Nationwide Registration Study. Am J Ophthalmol.2017;175:169-172. 10.1016/j.ajo.2016.12.015
[4] University Hospitals of Leicester NHS Trust. Treatment options for a cone-shaped cornea (keratoconus). Patient information leaflet. https://www.uhleicester.nhs.uk/wp-content/uploads/2025/06/1203_072021-Treatment-options-for-a-cone-shaped-cornea-keratoconus.pdf
[5] Hashemi H, Heydarian S, HooshmandE, et al. The Prevalence and Risk Factors for Keratoconus: A Systematic Review and Meta-Analysis. Cornea. 2020;39(2):263-270. 10.1097/ICO.0000000000002150
[6] Ng SM, Hawkins BS, Kuo IC.Trans-epithelial Versus Epithelium-Off Corneal Cross linking for Progressive Keratoconus: Findings From a Cochrane Systematic Review. Am J Ophthalmol.2021;229:274-287. 10.1016/j.ajo.2021.05.009
[7] Gomes JAP, Hafezi F, Ambrosio R,et al. Global Consensus on Keratoconus and Ectatic Diseases-Edition 2. Cornea.2026;45(7):888-908. 10.1097/ICO.0000000000004170
[8] Chen R, Ou X, Zeng Q. Risk factors for keratoconus: a systematic review and meta-analysis. BMC Ophthalmol.2026;26(1). 10.1186/s12886-026-05218-5
[9] Imperial College Healthcare NHS Trust. Corneal cross-linking: information for patients, relatives and carers(as of August 2023). https://www.imperial.nhs.uk/~/media/website/patient-information-leaflets/ophthalmology/corneal-cross-linking.pdf
[10] Alajmi TS, Alasmari FF, AlasmariTF, et al. Comparison of epithelium-off versus iontophoresis-assisted transepithelial corneal collagen cross-linking in keratoconus: a systematic review and meta-analysis. Int Ophthalmol. 2026;46(1):107. 10.1007/s10792-026-03977-0
[11] De Clerck EEB, Kruger J, Kropp M,et al. Corneal Allogeneic Intra-stromal Ring Segments for Treating Keratoconus:Systematic Review and Meta-Analysis. Medicina (Kaunas). 2026;62(3):523. 10.3390/medicina62030523
[12] Fairaq R, Kirat O, AlMutlak M, etal. Changing Strategies in Keratoplasty After Corneal Hydrops: From Penetrating to Lamellar Approaches. Clin Ophthalmol. 2026;20:568953. 10.2147/OPTH.S568953
