Keratoconus

What is Keratoconus?

Keratoconus is a greek word that means “conical cornea”  a condition where the front surface of your eye (the cornea) is no longer round like a soccer ball but a more oval like an AFL football.

What this means is that when the light hits your eye it no longer focuses clearly on the back of the eye but rather it is blurred or has glare/haloes around what you are seeing.

Keratoconus is a degenerative process affecting the cornea.  It usually affects both eyes but one eye may be much worse than the other.

Whilst keratoconus is a genetic condition it is not necessarily passed on in families.  One in 12 people with keratoconus has an affected relative.  If there is a not a definite family history of keratoconus then there is only a one in ten chance of the children of someone with keratoconus also having it.

Keratoconus is often associated with allergic disorders such as asthma, eczema and hayfever. It is also more common in people with sleep aponea.

For a while spectacle lenses can help to correct your vision.  Spectacles can correct both spherical refractive error (when the soccer ball is too curved or too flat) or regular astigmatism like the shape of an AFL football.

If the condition progresses you can get something called irregular astigmatism, think of it like an AFL football that is a bit more out of shape.  Then spectacles can no longer provide the clearest vision possible. For that you will need a contact lenses.  Fortunately most people can still use glasses some of the time but they may not be good enough for driving particularly at night.

Usually someone with Keratoconus has seen an Ophthalmologist (eye doctor) to have their condition diagnosed and baseline measurements taken.  Whilst there are many surgical options to correct Keratoconus they are only used when the easier and safer options of spectacles and contact lenses no longer provide good vision.

Not everyone with Keratoconus continues to progress.  In fact most people we see at Eye5 have stable keratoconus and don’t require any surgical correction.  The good news is with time the technology available to treat keratoconus both in contact lenses and surgical techniques is getting a lot better.  This means that the longer you can wait before having any surgery the better outcome you are likely to get.

Does rubbing my eyes make Keratoconus worse?

Anecdotally from people we see there appears to be a link between Keratoconus progression and eye rubbing.  There is also a link between allergies and Keratoconus progression that may be related to the rubbing of your eyes when they are itchy.  The best advice we can give you is not to rub your eyes ever.  If they are itchy please see us for help we can offer to improve the comfort of your eyes and contact lenses.

Have you been diagnosed with Keratoconus?

Perhaps you have been told that you can’t get good vision with spectacles and now need to consider wearing contact lenses.  You might have been told you have to wear hard lenses to see properly.  Thankfully that is no longer the case with many options from soft, hybrid and rigid gas permeable lenses available to provide clear comfortable vision.

What are the vision correction options for Keratoconus

Nothing

Sometimes people continue to see very well without any correction.  We can measure the shape of your cornea using our topographer and document your level of vision to ensure you meet the driving standard.

Spectacles

In early keratoconus and in cases which are mild spectacles continue to work well.  You might have some astigmatism and need a careful eyetest to ensure that is measured correctly but otherwise you will be able to wear glasses and sunglasses like anyone else.

Soft contact lenses

Again in early Keratoconus we can often fit you with disposable soft spherical or toric contact lenses.   These are great for playing sport and to give you an option other than glasses when going out.

Rigid Gas Permeable (Hard) contact lenses

Have been the mainstay of Keratoconus correction for decades.  When the shape of your cornea progresses the soft lens continues to wrap to that shape like cling film.  That means that they no longer provide clear vision.  That is when a rigid gas permeable or RGP lens is required to provide a clear refracting surface in front of your cornea.

These contact lenses retain their shape on the eye rather than wrapping to it like a soft contact lens.  The gap between the contact lens and your cornea is filled in with tears that help to smoothe out any irregularities on the surface and give you clearer vision.

Hybrid contact lenses

Are our speciality.  Half way between a soft lens and a hard lens with the best of both worlds.  Clear comfortable vision all day long.  They combine a highly oxygen permeable hard centre resting on a soft outer edge made from silicone hydrogel which is also very oxygen friendly.  The aim is to provide the clearest vision possible from the RGP centre combined with the comfort of a soft outer edge.

Scleral Contact Lenses

Are used in advanced cases of Keratoconus or where we cannot get an acceptable fitting with a Hybrid contact lens or RGP contact lenses.  The much larger scleral contact lens that rests on the white of your eye and vaults over the entire cornea.  The gap under the lens is filled with tears or ocular lubricants to provide a moist reservoir against the corneal surface.  This makes the lens very comfortable and provides the clearest possible vision.  These lenses tend to be more comfortable than RGP lenses as they rest on the white of your eye (less sensitive) and vault over the entire cornea.

Piggyback contact lenses

A piggyback contact lens fitting is where you use a soft disposable lens underneath an RGP lens.  The RGP lens provides the clear vision whilst the soft lens protects the cornea underneath from rubbing.  Whilst this sounds like a great idea in theory it has not lived up to expectations in practice.  Often this is used by practices who cannot obtain an acceptable fitting with RGP lenses and is a compromise.  Piggyback contact lenses are more expensive, because you need the soft lens as well.  They are also more complicated to care for with different solutions for both the hard and soft lens.

Most people we see for the first time with this are able to be refitted into a normal RGP lens or Hybrid contact lens and have no further need of a piggyback contact lens.

What effect with Keratoconus have on my life?

For most people with keratoconus they live completely normal lives.  Some people will manage fine with glasses but many will need to wear contact lenses.  A small proportion of people with keratoconus will need a corneal transplant.

Can I do anything to stop it getting worse?

It is known that eye rubbing makes it worse and this is more common if you have allergies or hayfever.  It is a good idea to treat the allergies rather than rub your eyes and risk making the keratoconus worse.  Using eye drops such as Zaditen or other anti-histamines can reduce the itching and thus the feeling that you want to rub your eyes.  Wearing contact lenses does not stop keratoconus getting worse but does improve your vision so you can do everything you want to do.

What is a corneal transplantation?

Corneal transplantation may be necessary if your vision cannot be corrected with contact lenses and you have tried all the different types such as soft, hybrid, RGP (hard) and scleral lenses

Key Points

• We can help people with mild, morderate and advanced Keratoconus
• Yes spectacles can help, maybe not all the time but they are great to have when your eyes are tired and you want to give them a break from contact lenses.

For more information on how we can help please contact us.