Light passes into the eye through the cornea, the eye’s transparent tissue in front. The shape of the cornea is like a dome, however, in rare cases, it bulges forward like a cone. As a result, the distorted cornea does not adequately focus light, even with glasses and traditional soft contact lenses. This medical disease is known as keratoconus and can progress especially during the teenage years and early twenties. This short guide will help you understand what causes keratoconus, its symptoms and available treatment options.
What Causes Keratoconus
Your cornea consists of tiny fibers of the protein known as collagen. When bonds between these fibers deteriorate, the cornea loses its smooth, normal shape, leading the cornea to become cone-like. Keratoconus has a known genetic link, so if you or anyone in your family receives a keratoconus diagnosis, then you’ll want to schedule regular checkups with your optometrist. Even so, one large study found that only 14% with keratoconus can identify another family member with the condition. In addition to genetic predisposition, some researchers believe that eye rubbing can worsen the distortion of the cornea. An unusually large number of patients with keratoconus report a tendency to rub their eyes, which is why your doctor may prescribe medicated drops to extinguish the itch.
Symptoms of Keratoconus
Symptoms of keratoconus usually first develop when the disease is progressing especially during the teenage years to the early twenties. The most common symptom is poor, blurry vision, which worsens during the consecutive years. It is important to realize that while keratoconus may affect as many as 1 out of every 375, that many other more common eye conditions share many of these symptoms. Therefore it is essential for you to have a proper examination so that you receive an accurate diagnosis. Keratoconus cannot be diagnosed only by symptoms alone. Objective clinical signs and measurements require the expertise of your eye doctor.
1. Vision Change in One Eye
In the early stage of the disease, patients may experience several changes to their eyeglass prescription within a relatively short period. One of the hallmarks of keratoconus is that even with updated glasses, vision is still reduced, often out of one eye. However, squinting can improve the vision temporarily.
2. Blurred Objects Near and Far
Those with keratoconus often complain of poor vision at all distances even with the best eyeglasses or soft contact lenses. This condition is what’s known as “irregular astigmatism” which blurs vision near and far.
3. Blurry Night Vision
Patients with keratoconus almost always experience greater difficulty with vision under dim lighting like driving at night. It’s not unusual for those with keratoconus to notice multiple images and halos, especially at night, even with updated eyeglasses and soft contacts.
4. Itchy Eyes
Itchy eyes alone are not an indicator of keratoconus. But if your eyes are so itchy that you find yourself regularly rubbing, AND you are experiencing the symptoms described previously, there is an increased possibility you may have keratoconus.
If you are or suffering from all four of these symptoms of keratoconus, or have in the past, you should seek a professional eye exam to obtain a diagnosis and rule out the existence of keratoconus.
Today there are several different treatment options for keratoconus. For those with mild disease, eyeglasses and soft disposable contact lenses may sufficiently help. For more advanced cases, special rigid-surface contact lenses are necessary to restore adequate vision. Specialty contact lenses remain the mainstay of rehabilitating vision for the majority with keratoconus, and today they include custom large-diameter scleral contact lenses.
There are also surgical treatments including corneal cross-linking which can help prevent further deterioration for those with the progressive but mild disease, and Intacs which is the implantation of plastic segments into the layers of the cornea to reduce the level of distortion. For a minority with severe symptoms of keratoconus where all non-surgical treatment has been exhausted, a corneal transplant might help. Corneal transplantation involves using corneal tissue from a deceased donor to replace the diseased corneal tissue.
Steps to Take
If you feel that you are suffering from symptoms of keratoconus, the first thing you should do is schedule an appointment with an eye doctor. Your optometrist has a wide range of tools to assess whether your symptoms are due to keratoconus or another ocular condition. The good news is that there are many effective treatments for keratoconus today. Dr. Brian Chou is nationally recognized as one of the top doctors to see for keratoconus. His scleral lens clinic regularly restores the quality of life for keratoconus patients that have lost hope. Contact ReVision Optometry today for a comprehensive eye examination.