Keratoconus

What is keratoconus?

Keratoconus is a progressive thinning and steepening condition of the cornea. Normally, the outermost layer of the eye, or cornea, is a smooth an evenly-rounded surface that refracts light in a uniform fashion. With keratoconus, the cornea becomes thinner, weaker and thus unable to support the shape, creating a bulge that affects vision. The exact cause of keratoconus is still uncertain (likely a combination of genetics and the environment) but the number of patients, especially in Oman, makes it one of the most common conditions seen on a daily basis.

What are the symptoms of keratoconus?

Keratoconus often starts already during the teenage years with blurring or distortion of vision and possibly light-sensitivity. A usual complaint is needing new glasses or contact lenses more frequently. Often, the prescription changes towards more nearsightedness and astigmatism. Known associations between keratoconus and certain other conditions exist, such as vernal keratoconjuncivitis and Down's syndrome.

How is keratoconus diagnosed?

A keratoconus diagnosis can only be confirmed by an ophthalmologist but a visit to your optician or optometrist can raise suspicion enough to refer you for further evaluation. In either case, a full eye examination, corneal topography mapping along with clinical findings and patient history lead to a final diagnosis. With unconfirmed cases where suspicion is raised, your ophthalmic care provider is likely to ask you for a follow-up visit to repeat the investigations.

How is keratoconus managed?

All possible management options are available at Finland Eye Center from non-invasive to surgical. In the early stages, special contact lenses can be fitted. However, while some patients can control their keratoconus this way for some time, many will find that contact lenses become insufficient. Another option available at FEC is the implantation of intracorneal rings (ICR). These tiny semi-circular devices can be placed inside the cornea in a quick out-patient session to provide more effective support and flattening of the cornea. Please see 'Intracorneal Rings' leaflet for more information. A further option is corneal cross-linking (CXL), which can be highly effective even at halting the progression of keratoconus. This is a combination of riboflavin (Vitamin B12) and UV-A light applied to the cornea to strengthen the structure. Please see 'Corneal Cross-Linking' leaflet for more information.

Should your keratoconus advance beyond a certain point you will be advised for corneal grafting, with all the most modern types also available at FEC. Corneal grafting is a significant operation but is a last resort option for advanced or unresponsive keratoconus.

Keratoconus management is undergoing a major shift in that nowadays the trend is to start keratoconus management as early as possible to get the maximum benefit from the least invasive options, even for young patients or children. This way, less invasive options can be more effective and unnecessary delay can be avoided to maintain visual acuity.

Note: It should be understood that due to the progressive nature of keratoconus and the lack of an exact cause, options for keratoconus are mainly for management, delaying progression or attempting to halt the progression. A 'cure' has yet to be discovered.