How serious is keratoconus?

Keratoconus is a disorder that affects the front part of the eye (the cornea). If you’ve been diagnosed with an eye condition that you may not know much about, it can feel daunting. Many questions will run through your mind, such as just how serious is it? Will I lose my vision? Will I need surgery?

We’ve asked leading eye specialist Dr CT Pillai to explain what happens to the eye if you develop keratoconus and how it can be managed.
 

Can you go blind with keratoconus?

Total blindness is not associated with keratoconus. It is a disease of the front surface of the eye, which causes it to bulge outwards in an irregular cone shape. This makes the vision distorted and blurry but can somewhat be improved with glasses or contact lenses.

Due to the uneven and irregular shape of the cornea, light entering the eye scatters more and can cause halos around artificial lights that affect the quality of vision, especially at night.

A rare complication of keratoconus, called hydrops, can cause significantly more severe visual symptoms. This is when fluid from inside the eye accumulates inside the cornea through breaks in the corneal endothelium (back surface) and causes the cornea to swell and become cloudy or milky in appearance.

Adequate medical management is imperative during this complication but even after it has resolved, a keratoplasty (corneal transplant surgery) is often required. [1]
 

Can keratoconus be reversed?

Keratoconus cannot be reversed, but it can be slowed down and stabilised with Collagen Cross-Linking. This is the only treatment available that halts the progression of the condition and partially reverses the corneal steepening caused by the disease.

I have been performing Collagen Cross-Linking treatment since 2007. We offer epithelium-off treatment, which is when a corneal flap is created in the thin outer layer (epithelium) of the cornea to allow the liquid Riboflavin (Vitamin B12) to more easily penetrate the corneal tissue whilst being exposed to UV light.

This non-invasive procedure often eliminates the need for a corneal graft.

The progression of the condition is halted through the process of photopolymerisation, which is caused by the addition of Riboflavin under UV light. This leads to oxygen radicals, enabling for the development of strong collagen bonds. This technique strengthens the chemical bonds in the cornea, which increases the thickness and stabilises the cornea, consequently stopping the progression of the disease. Treatment is only required once and is effective in 97% of cases [2].
 

What does keratoconus treatment involve?

Cross-Linking is used to halt the progression of the disease. The treatment for keratoconus doesn’t aim to reverse or cure the condition, but rather it is considered more of visual rehabilitation. The aim is to give patients the clearest possible vision.

The most common forms of visual correction are glasses and contact lenses. Contact lenses tend to be more successful for keratoconic patients as there are multiple specialist contact lenses specifically manufactured for these patients and designed to fit over the cone-shaped cornea.

Options include: custom soft contact lenses (Kerasoft, NovaKone), rigid gas permeable contact lenses, piggyback contact lenses, hybrid contact lenses (UltraHealth, ClearKone), scleral and semi-scleral lenses.

It is useful to note that contact fittings for keratoconic patients can be a long and arduous process due to the fluctuating vision. Multiple visits will be required in order to achieve satisfactory vision and comfort in contact lenses, however, once the initial fitting is completed the contact lens parameters usually remain the same for some time.

Some patients are suitable for refractive surgery, which is an alternative to glasses and/or contact lenses. Mainly ICL (Implantable Contact Lenses) and Lens Replacement Surgery. ICL surgery involves the surgeon placing a micro-thin contact lens in the eye, just behind the iris.

This lens has been manufactured and surfaced with the patient’s prescription already, which means that patients who undergo this procedure are much less dependent on glasses or contact lenses. Lens replacement surgery (age 45 years onwards) involves replacing the eye’s natural lens with an artificial lens implant, which has the patient’s distance prescription in it.

Clinics are conservative in their approach to treating keratoconic patients with refractive surgery because they will never be able to achieve good quality of vision. However, those who understand and accept the limitations of the visual outcome are often good candidates [3].

Intacs are small arc-like segments which are inserted into the middle layer of the cornea in order to flatten the cone-like shape slightly. For certain cases, Intacs can help improve the vision [4] and also aid in making them slightly more contact lens tolerant.

This treatment is very specific to individual cases and would require a thorough assessment in order to establish suitability. We have a specialist keratoconus clinic at my clinic in London, Advanced Vision Care. I always prefer to carry out an individual assessment before recommending potential treatments.
 

Will I need a cornea transplant?

Only advanced and severe cases of keratoconus require corneal transplants. This needs to be assessed by a specialist.
 

Is keratoconus considered a disability?

Keratoconus itself is not considered a disability, but the visual loss caused by the disease may be severe enough to qualify as a disability. This is assessed on a case-by-case basis.

Do not hesitate to book an appointment with Dr Pillai if you’re worried about your eyesight.

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References
1] Maharana, P. K., Sharma, N., & Vajpayee, R. B. (2013). Acute corneal hydrops in keratoconus. Indian journal of ophthalmology, 61(8), 461–464. doi:10.4103/0301-4738.116062
[2] Strmeňová E, Vlková E, Michalcová L, Trnková V, Dvořáková D, Goutaib M, Němec J, Gerinec A. The effectiveness of corneal cross-linking in stopping the progression of keratoconus. Cesk Slov Oftalmol. 2014 Dec;70(6):218-22
[3] Ormonde, S. (2013), Refractive surgery for keratoconus. Clin Exp Optom, 96: 173-182. doi:10.1111/cxo.12051
[4] Rabinowitz YS. INTACS for keratoconus. Int Ophthalmol Clin. 2006;46(3):91–103.