Most people go to the eye doctor, have an exam, and receive corrective lenses that allow them to experience good vision. However, one out of about every 2,000 people don't get good vision even with corrective lenses because they have developed a condition called keratoconus. Keratoconus is a progressive disease that affects the shape of the cornea. It can be diagnosed during a routine eye exam.
What is Keratoconus?
Keratoconus causes a malformation of the cornea, called astigmatism, which generally progresses until the cornea is cone-shaped. During the earliest stages of the disease, corrective lenses can correct or almost correct the patient's vision. However, as the disease progresses, it becomes increasingly difficult and then impossible to correct the patient's vision with glasses or contacts.
As the cornea becomes more misshapen, wearing contacts becomes increasingly uncomfortable and even intolerable. Keratoconus generally appears during the teen years and progresses through the patient's 30s or 40s, at which time the progression slows significantly.
What Causes Keratoconus?
The causes of keratoconus aren't well understood by medical scientists. One factor seems to be genetics, while behavioral and environmental causes may also contribute to the disease. Eye rubbing, trauma to the eye, sleep apnea, and floppy lid syndrome all have correlations to keratoconus.
How Do Doctors Diagnose Keratoconus?
Keratoconus is generally detected during a routine eye exam, but diagnosing the condition in the early stage does require additional tests. During the moderate to advance stages, eye doctors can see the malformation of the cornea during an exam called corneal topography, in which the doctor uses light and a machine to map the topography of the cornea digitally. During the early stages there are subtle changes noted on a topography map.
Doctors can also use keratometry, which focuses a circle of light onto the cornea and examines the light reflected off of the cornea to determine curvature. In advanced keratoconus, doctors can use a slit lamp to detect corneal curvature. The slit lamp uses a tiny but intense beam of light to examine the eye.
What Can Be Done to Treat Keratoconus?
Once diagnosed, treatment depends on the stage of the disease. Those with early to intermediate stage keratoconus might be served well by soft contacts or glasses to correct their vision. As keratoconus progresses through the intermediate stage, these lenses may not increase the quality of your vision, and the doctor can use tonic soft lenses, rigid gas-permeable lenses, or a combination of hard and soft lenses to get a good balance of clear vision, comfort, and a great fit.
As keratoconus advances, however, a patient becomes in danger of needing a cornea transplant.
There are several options that help avoid the need for a cornea transplant, including Intacs and Holcomb C3-R. Intacs are like a permanent inserts that are placed into the layers of the cornea. For patients who are good candidates for Intacs, this procedure helps to decrease the irregular cornea surface and improve vision. Holcomb C3-R is a treatment in which a combination of special eye drops and UV light are used to stabilize the condition and stop further progression. The Holcomb C3-R procedure is one that should be consider even in the early stages of Keratoconus to help preserve the current vision.
In patients where Intacs or Holcomb C3-R were not performed, a patient can become progressively at risk for a cornea transplant. This procedure involves removing the patient's misshapen cornea and replacing it surgically with a donor's cornea. The recovery for this procedure can be painful and take up to 1 year. This is why more and more patients are seeking out Intacs and Holcomb C3-R in the early to moderate stages of Keratoconus.
Only an eye doctor experienced in treating keratoconus can determine which procedure is the best option for each individual patient.