Keratoconus Treatments

Keratoconus treatments are recommended based on individual circumstances taking into account the stage of progression, age and patient lifestyle amongst many other factors. Corneal specialists agree that it is best to exhaust all non-surgical options before undergoing corneal transplant surgery. Introductions of new technologies and treatments continue to push forward the boundaries of keratoconus management.

The treatment ladder for keratoconus is complex. Outlined below are a few of the latest, clinically proven methods that help patients. It is not uncommon for treatments to be combined to obtain the very best outcomes.

Contact Lenses offer an excellent method of improving vision in the early stages of keratoconus. Options of suitable contact lenses include:

• Soft, toric contact lenses
• Hybrid contact lenses
• Rigid (hard) gas-permeable (RGP) contact lenses
• Mini-scleral contact lemses
• Scleral contact lenses

Cross-linking is not a new technique and has long been used as a medical interventional technique. Commonly used to modify the strength of substances (such as fillings in dentistry), cross-linking has been used for a number of years in ophthalmology. 

It is a non-surgical method utilising an Ultra Violet A light source, which is delivered onto the cornea together with a chemical mix largely made up of riboflavin for strengthening the collagen fibres within the corneal structure.  The combination of the UVA light and the riboflavin creates a joining or bonding of the chemical structures within the cornea. (Riboflavin is commonly found in our food and also known as vitamin B₂, which is an easily absorbed micronutrient with a key role in maintaining health in both humans and animals). 

This comparatively simple procedure has been shown in laboratory and clinical studies to increase the amount of collagen cross-linking in the cornea and subsequently strengthen the cornea. There are published European studies, to show that this Cross Linking procedure has been proven safe and effective in patients with no side effects reported. Additionally, retreatment is an option at a later date if required.

Cross-linking therapy is being used for a number of diseases of the cornea and is proving a useful treatment in conjunction with other surgical techniques such as Intacs and refractive laser surgery. However Cross linking is not for everybody, the first requirement is to ensure that the thickness of the cornea is adequate for the treatment. Special non-invasive measuring devices are used by your specialist to accurately and quickly take these readings.

The insertion of corneal rings is a surgical procedure. These rings are small, clear, semicircular  plastic rings of various thicknesses, which are inserted inside the cornea at its outer edges. Their insertion flattens the central area of the cornea and corrects myopic refractive errors.

A major advantage of this procedure is that no tissue is removed and there is no ablation or incision across the visual axis. INTACs and Kerarings have been proven to stop or slow down the progression of keratoconus, although often glasses or contact lenses will be required.

For the very best results, femtosecond laser insertion of rings offers the greatest accuracy and safety.

Certain types of modern excimer lasers can now be programmed to follow the exact shape of an individual cornea, thus allowing precise reshaping of the cornea. In patients with keratoconus, the laser can remove the bulge and return the cornea to a more regular shape. this treatment will not allow a keratoconic patient to get rid of their glasses like normal refractive surgery, it greatly reduces their dependence on certain types of contact lenses. For patients who are experiencing significant glare and haloes, T-CAT laser can vastly improve the quality of vision

Such treatments must be performed with Corneal Collagen Cross Linking in order to strengthen the cornea. This reduces the risk of a further change in shape in time. T-CAT laser is at the very forefront of keratoconus treatment and is only available in some specialist centres.

The Implantable Contact Lens (ICL) has been available for over 20 years and is custom made for each individual, The lens is a micro-thin implant that is able to correct the often very high prescriptions associated with keratoconus, ranging from +8.00D longsightedness  to -20.00D short-sightedness, whilst also correcting up to 6.00D of astigmatism.

The lens is designed to be inert and 100% compatible with the natural environment of the eye. Other advantages of the material include UV-A and UV-B protection, anti-reflectivity and exceptional optical clarity.

The ICL is implanted through a small 2.2mm entry and is gently positioned behind the iris and infant of the natural lens. Once implanted, the lens is invisible to the naked eye and cannot be flat within the eye. The procedure takes less than 15 minutes to perform and is often performed under local anaesthetic, meaning patients are able to walk out of the surgical theatre once finished. For patients who are anxious, general anaesthesia or sedation can be administered.

The ICL is a reversible procedure meaning that in the future, the lens can be removed should the need arise for any reason.

When all else fails, corneal transplantation remains an excellent method for improving the vision in advanced cases of keratoconus. However it is only undertaken after ruling out other treatment options.

As an invasive surgical procedure, corneal transplant surgery does pose a small but potentially serious risk to the eye. There are several reasons to be cautious when deciding if a corneal transplant is a viable option

Traditional full thickness grafts are termed ‘Penetrating Keratoplasty’ (PK). Such transplants carry a greater risk of complications such as graft rejection.  PK has limited lifespan and for the younger patient, the probability of rejection and failure is therefore greater and a second corneal transplant would be required.

The absence of blood vessels in the cornea means that the healing process is slow and it may take a year or even longer before the shape of the transplanted cornea (and effectiveness as a focusing lens) has stabilised.  During this time, vision in a transplanted eye would often not be functional.

A newer technique is a partial corneal graft, which is termed ‘Deep Anterior Lamellar Keratoplasty’ (DALK). This is the preferred method for corneal transplantation. This technique has been practiced commonly for the last decade. It replaces the main structural layer (known as the stroma) but preserves the innermost layer of the cornea (known as the endothelium). This means that if initially successful, there is a very low chance of failure or rejection later on like PK.

There is a risk that even after absolutely perfect surgery, the healing process could be distorted causing the graft to become mis-shaped, creating abnormal astigmatism.