Keratoconus
Symptoms, causes, treatment, and when to see an optician
Overview
Keratoconus is a progressive condition in which the cornea — the clear, dome-shaped front surface of the eye — gradually thins and bulges outward into a cone shape. This distortion causes increasingly blurred and distorted vision that cannot be fully corrected with standard glasses. It typically begins during the teenage years or early twenties and may progress for 10 to 20 years before stabilising. Keratoconus affects approximately 1 in 450 people in the UK.
Symptoms
- Progressively worsening blurred and distorted vision
- Frequent changes in glasses or contact lens prescription
- Increased sensitivity to glare and bright lights
- Ghosting or multiple images (monocular diplopia), especially at night
- Difficulty with night driving
- Vision that is no longer fully correctable with glasses
- Eye strain and headaches
Causes & Risk Factors
- Weakening and thinning of the collagen fibres in the cornea — the exact underlying cause is not fully understood
- Genetics — keratoconus can run in families, though many cases have no family history
- Eye rubbing — vigorous and habitual rubbing is a significant and modifiable risk factor
- Allergic eye disease, eczema, and hay fever — the itching associated with these conditions may lead to eye rubbing
- Down syndrome and certain connective tissue disorders are associated with higher prevalence
Treatment Options
In the early stages, keratoconus can often be managed with glasses or standard soft contact lenses. As the condition progresses, however, the irregular corneal shape means that standard lenses can no longer provide clear vision. Rigid gas-permeable (RGP) contact lenses are the mainstay of optical correction for moderate keratoconus, as they create a smooth, regular refracting surface over the cone. Scleral lenses — large-diameter rigid lenses that vault over the entire cornea — have become increasingly popular in the UK, offering excellent vision and comfort even in advanced cases.
Corneal collagen cross-linking (CXL) is a treatment that strengthens the cornea and halts the progression of keratoconus. It involves applying riboflavin (vitamin B2) drops to the cornea and then exposing it to controlled ultraviolet light. Cross-linking was first approved in the UK and is now available on the NHS for patients with progressive keratoconus. It is most effective when performed early, which is why regular monitoring and early detection are so important.
For advanced cases where contact lenses can no longer provide adequate vision and cross-linking has not been performed in time, corneal transplant surgery (keratoplasty) may be necessary. The UK has a well-established corneal transplant service, and modern techniques — particularly deep anterior lamellar keratoplasty (DALK) — have excellent outcomes with lower rejection rates than full-thickness grafts. Intrastromal corneal ring segments (ICRS, such as Intacs or Kerarings) are another option that can improve the corneal shape and vision in some patients, either as a standalone treatment or as a bridge to better contact lens fitting.
Prevention Tips
- Avoid rubbing your eyes — this is the single most important modifiable risk factor for keratoconus progression
- If you have allergies or eczema that cause itchy eyes, use antihistamine drops rather than rubbing
- Have regular eye tests during your teenage and young adult years, when keratoconus typically develops
- If keratoconus is diagnosed, attend monitoring appointments faithfully so progression can be detected and cross-linking can be offered in time
- Inform your optometrist if you have a family history of keratoconus
When to See an Optician
Book an eye test if your vision is becoming increasingly blurred or distorted, if your glasses prescription is changing frequently, or if there is keratoconus in your family — early detection allows for timely cross-linking treatment that can prevent progression.
Key Facts
- Category
- Common condition
- Typically Affects
- Usually develops between ages 10 and 25; may progress until the 30s or 40s
- Key Symptoms
- 7 identified symptoms
Related Conditions
Detecting Keratoconus
The following eye tests can help detect signs of keratoconus:
- Standard eye test
- OCT retinal scan
- Visual field test
Protect your vision with a regular eye test
Early detection is key. A routine eye test can identify signs of keratoconus before symptoms become noticeable. Book yours today.
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