Keratoconus is a condition where the part of the cornea near the center becomes thinner and takes a conical shape. As a result, vision is impaired.
Keratoconus does not cause complete blindness, however, it can lead to significant visual impairment if not treated. With the current treatments, most patients with keratoconus can continue their normal lifestyle.
Keratoconus is a progressive eye disease that usually affects both eyes. The degree of progression in both eyes is generally uneven, and the condition can be significantly more advanced in one eye.
Causes of keratoconus
The cause of keratoconus is unknown. However, there are studies showing that it is a hereditary condition. Some studies have linked keratoconus to allergies such as asthma and eczema. It has been found that poorly fitted contact lenses and excessive friction of the eye can also contribute to this.
Do not rub your eyes!
Patients with keratoconus should avoid rubbing their eyes. This can damage fine corneal tissue and make your symptoms worse.
If you have itchy eyes that cause you to rub, you need to use medicines to control your allergies.
The first sypmtom of keratoconus stands out to be a change in diopter value and a decrease in vision due to an irregularly shaped cornea. This may not be obvious at first, but will become more noticeable over time.
Vision is usually affected when it starts to change the cornea shape. Blur, light sensitivity and misty images can be seen.
Keratoconus begin to develop in their early 20s in most people and the majority of transplants are applied to patients aged 20-45.
Can keratoconus harm vision?
Untreated keratoconus can lead to permanent vision loss. Changes in the cornea make it difficult to see with glasses or with standard soft contact lenses or without glasses.
If laser eye surgery like LASIK is performed on the eye, it may worsen the situation. Anyone with a small degree of keratoconus should not undergo laser eye surgery in very specific situations unless recommended by the doctor.
How is keratoconus treated?
There are several methods to treat keratoconus, depending on how severe the condition is. In the early stages of the disease, vision can be corrected with normal glasses or soft contact lenses.
As keratoconus worsens, vision may no longer be corrected with glasses due to irregular amount of astigmatism, and therefore a special type of hard contact lens may be required for the patient.
For some patients, the disease can progress to a stage where they do not have an acceptable vision, even with glasses or contact lenses. At this point, a corneal transplant, a surgical procedure, may be recommended to replace the cornea from a cornea of a donor.
Two additional treatments for keratoconus are implantable ring segments (often called INTACS) and corneal cross-linking:
Implantable ring segments are small devices placed on the cornea to improve vision or make it easier to attach contact lenses to a patient. In this procedure performed under local anaesthesia (the patient's eye is anaesthetized with drops), channels are created in the cornea and rings are placed in these channels. The rings help straighten the cornea and partially correct the cone shape caused by keratoconus.
Corneal cross-linking is the ultraviolet light therapy that can slow or stop the worsening of keratoconus. In this procedure, the patient is given local anaesthesia. A drop containing riboflavin (vitamin B2) is instilled into the eye for up to 30 minutes. The eye is then exposed to ultraviolet light for up to 30 minutes. The corneal cross-linking procedure is designed to strengthen the bonds between the collagen fibers of the cornea and the surrounding proteins, which can help prevent the cornea from erecting.
Not all patients with keratoconus are candidates for these treatments. We need to decide together on which of these treatments can help you.