Years of observation, thought and research has revealed many causes of keratoconus. What is actually a cause is often difficult to pin point definitely.
Keratoconus causes can include: eye-rubbing, hormonal activity, collagen disorders and genetics.
While we can’t do much about the last three, eye-rubbing is certainly something we can tackle. Progression (worsening) of the disease is also related to poor contact lens fit.
Keratoconus and Eye Rubbing
Did you know that the disease can be induced and certainly made worse by unnecessary eye rubbing?
When we see you for the first time, we support you in every possible way we know to make sure you understand the implications of eye rubbing with keratoconus.
We work with you to find strategies to minimise eye rubbing. Two of the biggest culprits in causing eye-rubbing are Dry Eye and Allergy.
While dry eye doesn’t actually cause keratoconus, excessive eye-rubbing is strongly linked to progression of the disease.
When your eyes are dry, you often rub aggressively.
Clear instruction to teenagers on regular computer breaks in conjunction with blinking exercises will stimulate the natural lubrication system of the eyes. Where possible, you should avoid preserved eye drops, as your keratoconus makes you more likely to be irritated by the preservatives.
Eczema, asthma and allergic conjunctivitis (hay fever) often seems to be associated with keratoconus. The mechanical trauma that often occurs due to forceful rubbing of itchy eyes seems to make the disease worse.
What can you do about it?
Steroid eyes drops and antihistamines can be prescribed when there are signs of hay fever. Don’t forget cold compresses, as this very simple and natural treatment is super-effective for itchy eyes. Flexible cold packs that are kept in the freezer for sporting injuries are the most effective way of delivering a cold compress treatment. Do not forget to wrap the cold pack once in a tea towel before it is placed over the eyes, as it can be very cold and thus can irritate the surrounding skin.Read more about tips on reducing eye-rubbing
Most cases of keratoconus begin before the age of twenty. There are exceptions to this but the average person that we will see for the first time is a teenager around the age of fifteen.
It is generally accepted that during puberty and other times of hormonal change, there are excessive chemicals (called enzymes) present in your cornea, which cause it to thin. This is why we tend to first diagnose keratoconus during puberty. There have been many case reports of stable keratoconus, which all of a sudden progress during pregnancy when there is another surge of hormonal change.
Your cornea is made up of many collagen fibres. It is thought that if you have keratoconus, these fibres are weak and therefore stretch. When this occurs your cornea can weaken and deform. This in turn will cause your vision to blur and in many cases glasses cannot correct the vision.
Some patients with keratoconus also have floppy eyelid syndrome, obstructive sleep apnea and occasionally even mitral valve prolapse. These conditions are all collagen disorders.
Do all patients with keratoconus have these associated conditions? NO, THEY DO NOT. The take home message is that these conditions need to be checked for and managed appropriately if you have keratoconus.
The average patient that sees us for keratoconus will not know of another family member with the disease.
However, recalling family history is not accurate. Studies have shown a strong hereditary link. Only 8% of patients with the condition are aware of another family member with the disease, yet up to 50% of family members will in fact have a very mild, sub-clinical form of keratoconus (forme fruste).
This can only be diagnosed with very sophisticated technology and does not affect the individual on a day-to-day basis.
Poor contact lens fit
Properly-fitting hard contact lenses provide the best vision if you have keratoconus.
What is unfortunate though, is that their use often makes the disease worse if they are not fitted correctly.
Many patients are fitted with inappropriate, flat-fitting contact lens designs – often due to the inexperience of the practitioner.