Frequently Asked Questions answered by Lynn White MSc FCOptom, Clinical Director at UltraVision
First of all, if you have just been diagnosed, the likelihood is that your vision is not too bad at the moment. It is important to realise that most people who contribute to forums are those who have the worst problems. Those who are getting on fine simply just get on with their lives! Keratoconus is a progressive condition but the active stage often lasts about 10 years and many people stabilise before that. If you cannot get good vision with glasses, then most often you can with contact lenses, which enable you to get on with life normally. Most keratoconics fall into this category.
Keratoconus is generally more advanced in one eye than the other and many people only develop symptoms in one eye. It won’t “spread” like an infection, but as the condition is linked to weaker collagen fibres in the cornea, it is likely that both eyes could be affected to some extent.
Research is increasingly showing that keratoconus has some genetic components. Twins often have keratoconus and it does run in families. On the other hand, you may be the only person in many generations that has it. However, to offset this, it is possible that one of your ancestors may have had keratoconus but it was not diagnosed – it is more commonly recognised nowadays than in the past. So yes, it is possible but there is no current test to check if you can pass it on.
Generally, as long as you can reach the legal requirements of your country for vision whilst driving, you are fine. If you can only attain this when wearing contact lenses, you are advised to inform the relevant authority who will simply note that you have to wear contact lenses in order to drive. Some people have trouble, even with their contact lenses, driving at night as still they suffer from haloes and ghosting – especially facing oncoming traffic on unlit roads. If this is the case then it is better not to drive at night.
No. In keratoconus, the cornea becomes thinner and weaker. As laser treatment also thins the cornea (as you are lasering “away” part of the cornea), this simply makes the situation worse. In fact, if you have sub-clinical keratoconus, laser treatment will most likely accelerate the condition, so is not recommended.
Grafting is reserved for when there is vision loss due to scarring, distortion that cannot be corrected with contact lenses or the cornea becomes extremely thin. Usually all other treatment methods are explored before resorting to surgery and a graft. Many people still have to wear contact lenses after a graft in any case, as the front of the eye is still irregular.
Other surgical techniques include intracorneal rings and CXL (cross-linking;C3R) but both of these also may require you to wear contact lenses afterwards.
Many people can wear normal soft lenses in the early stages. Once keratoconus progresses, then these do not work because they simply mould to the irregular shape of the cornea. At this point, you can move onto specialist soft lenses such as the KeraSoft IC or RGPs (Rigid Gas Permeables). RGPs can give good vision – but often the best vision is obtained when the lens is fitted flat against the eye, which can lead to scarring if not corrected. RGPs are often uncomfortable as keratoconics tend to have more sensitive eyes than usual. If soft lenses do not give good vision, then piggy-backing an RGP on a soft lens may work. There are also hybrid lenses (centre RGP, surround soft) and sclerals (cover the whole eye). You are best advised by your eye care professional.
No. Solutions used for RGPs are too “strong” to use with soft lenses, which absorb any liquid they are put into. You have to use the appropriate solution for the lens you are wearing. Always check with your eye care professional if you are not sure.
It was once thought that contact lenses halted the progression of keratoconus – but this is not true. Rigid lenses may reshape and remould the eye but it will always “unmould” if you leave the lenses out. Intracorneal rings reshape the cornea in order to reduce the effects of aberrations and distortion, but do not stop the condition from progressing. CXL is the only surgical technique so far that appears to slow down the progression of keratoconus.
NO! Many keratoconics also suffer from allergic conditions and have dry eyes. This all leads to discomfort which makes you want to rub. However, rubbing your eyes will lead to further damage – in fact some people think that excessive rubbing may even be part of the cause of the keratoconus. So do NOT rub. Use cold compresses or just firmly press the eye, without actual rubbing.
Many keratoconics cannot wear RGPs for this reason. One way is to wear RGPs on top of a soft lens – piggy-backing. Another is to wear a specialist soft lens like KeraSoft IC, a hybrid lens or a scleral. In quite advanced keratoconus, you may not get as good vision in a soft as an RGP, but it may be worth the lower visual acuity to get the length of wear time. Hybrids can sometimes cause problems with oxygen transmission (though hopefully newer designs are better from this point of view). Sclerals are sometimes the only option – they cover the entire eye so do not cause surface irritation. However, if you have bad allergies the likelihood is that you will produce excess protein in your tears which can adhere to the lenses surfaces (deposits). Therefore, care has to be taken at all times to keep the lenses as clean as possible.
Many people with keratoconus have one eye that is much better than the other. It may have been like this for some time, so that the brain simply cannot work the two eyes together to produce a 3 dimensional image. In this situation, you do not have depth perception, so that tripping and general clumsiness is to be expected. Someone who only has the use of one eye from being very young adapts to it. If you lose your binocular vision as an adult, then it is much harder to adapt.
If you actually then regain good vision in your two eyes later on, through contact lenses or surgery, the brain then often has a hard time readjusting to using the two eyes together again! If your two eyes are “fighting” each other, this can sometimes cause headaches and fatigue.
Many countries have disability legislation that covers the workplace. This includes advice about dealing with employees who may have problems with vision. Keratoconics can be a challenge because if they are OK with contact lenses, then they are “normal” but if they have problems where they cannot wear their contacts, they suddenly become partially sighted for a period of time. Employers often find this hard to understand. The keratoconic self help groups can often be a rich source of information and support in this respect.