Keratoconus is a progressive eye disease in which the normally spherical cornea thins and begins to bulge into a cone-like shape. The cornea is a clear organ that lies in the central portion of the surface of the eye. In patients with keratoconus, the cone-shaped cornea cannot focus light rays properly and causes distorted vision.
Keratoconus often begins to develop in adolescent years. A variant called pellucid marginal degeneration (PMD) affects patients in older years. Changes in the shape of the cornea occur gradually, usually over several years. The cause of keratoconus is largely unknown. Some genetic links have been identified. Whilst most people with keratoconus are otherwise healthy, patients with Down’s syndrome, connective tissue diseases, and certain retinal conditions are at higher risk of developing keratoconus. Allergic eye disease associated with eye rubbing is present in about 30% of patients with keratoconus.
Keratoconus can be difficult to detect because it usually develops very slowly. Signs of keratoconus may include:
- Myopia (near sightedness)
- Astigmatism (uneven curvature of the eye’s surface)
- Double vision
- Headaches due to eye strain
- Glare
- Light sensitivity
Treatment
In the early stages of keratoconus, glasses or soft contact lenses may correct the near sightedness and astigmatism associated with the disease. As the condition progresses and the cornea becomes increasingly thin, more advanced treatment is required.
Collagen Cross Linking
This treatment works by strengthening the corneal tissue to slow down the thinning process. In this procedure, eye drops that contain riboflavin (vitamin B2) are applied to the cornea and then activated by ultraviolet light. This strengthens the collagen fibres within the cornea. Collagen cross linking increases the bonds between chains of collagen leading to an immediate and generally permanent increase in the structural strength of the cornea.
With today’s improved technology, the vast majority of people suffering from keratoconus and other corneal ectasia may safely undergo cross-linking. Our results show 100% efficacy at stabilising keratoconus at 2 years post treatment. Approximately half of the patients, experience an improvement in their astigmatism and contact lens fitting.
CXL can be combined with other treatment modalities such as Kerarings and topography-guided PTK to further improve the vision. Dr. Gupta will discuss the best treatment options for you during the consultation.
Keraring
Kerarings are tiny, transparent, semi-circular, plastic implants. These implants are used for patients who are no longer able to wear contact lenses comfortably. Kerarings are placed within your cornea to make its shape more normal. This improves the quality of vision and reduces myopia and astigmatism associated with the keratoconus.
Keraring implants are designed to make it more comfortable to wear hard contact lenses. In most patients this avoids the need for a corneal transplant. Kerarings may even improve your vision to the point where you can use soft contacts or glasses instead.
The procedure is performed using a femtosecond laser to create a channel in the cornea into which the Keraring is inserted. As the procedure is minimally invasive this allows patients to rapidly resume their normal activities.
Topography-Guided Phototherapeutic Keratectomy
TGPTK is an excimer laser treatment designed to reduce irregular astigmatism in Keratoconus. It can also be used to treat pronounced corneal irregularities, scarring and surgically induced irregular astigmatism beyond the range of wavefront sensing devices. The data is derived from corneal topography measurements, which allows treatment to be customized to each individual patient’s corneal profile. The treatment is often combined with collagen cross-linking to prevent progression of keratoconus.