Frequently Asked Questions
Who gets keratoconus?
Researchers estimate that keratoconus affects 1 in 2000 people. The disease affects men and women alike and there are no known differences between races. Although the cause of the disease is unknown, research has suggested that genetics, allergies and other environmental factors may contribute to the onset of the disease.
What are the symptoms?
Initially, a person with early stage keratoconus will notice a subtle change in their vision. As the disease progresses, one's vision will fluctuate and frequent changes to one's glasses or contact lenses often occur. This happens as a result of a thinning taking place within the cornea and bulging caused by one's normal eye pressure pushing on the weakened front surface of the eye. As the disease continues to advance, the light rays entering the eye become significantly distorted, called irregular astigmatism. The outer portion of the eye begins to bulge, creating what often looks like a cone shape.
Does keratoconus affect both eyes?
Yes, in approximately 90% of keratoconus cases the disease will manifest itself in both eyes. The rate of progression and the timing of the onset of the disease is typically different for each eye.
What is the usual age of the onset of keratoconus?
The onset of keratoconus can occur anywhere between the ages of 8 to 45. In the majority of the cases, it becomes apparent during the teen years and slowly worsens before stabilizing somewhat in the 30's or 40's.
How can it be treated?
Typically, an eyecare professional will treat early stage keratoconus with contact lenses or glasses addressing the early vision correction needs of the patient. In later stages, rigid gas permeable contact lenses are often recommended. These lenses are used to improve one's vision and to brace the bulge in the cornea. In advanced cases, where the patient can no longer achieve adequate functional vision with contact lenses, corneal transplant surgery may be necessary.
Will I go completely blind?
No, historically very few if any persons suffer from total blindness from keratoconus alone. But in severe cases, one's vision can be significantly impaired and normal everyday activities may be difficult.
How do Intacs work and how might they help me?
Due to the onset and progression of keratoconus, the weakened cornea looses its natural dome-like shape. As a result, the light rays entering the eye are no longer focused properly, impairing one's ability to see images clearly.
Intacs are specially designed inserts, made of medical plastic, which are surgically placed under the surface of the cornea. Due to their unique patented design, Intacs are able to remodel the architecture of the cornea re-establishing a more natural dome-like shape and improving one's vision.
Tell me more about corneal transplant surgery.
Of those who suffer from keratoconus, approximately 20% will undergo a corneal transplant. In the US, donor tissue is available in most instances and there are more than 4,000 transplants performed for keratoconus each year. The success rate is high although the grafts only last for about 10 years, therefore a young person may have to undergo several corneal transplants. The recovery time for the patient varies and can take more than a year. Contact lenses or glasses are typically required after surgery to achieve acceptable vision.
What are the advantages of the Intacs procedure as compared to a corneal transplant?
A corneal transplant is an invasive surgical procedure, requiring the removal of a section of your cornea and having it replaced with donor tissue. Although successful, it is a delicate procedure with typically a long recovery period.
The Intacs procedure does not require removal of corneal tissue, but rather works on the principle of reshaping your own cornea from within utilizing special designed corneal inserts that provide structure to a weakened cornea. The recovery period is typically short, with visual improvement noticed almost immediately.
In the few cases in which a corneal transplant was performed after an Intacs procedure, there were no complications reported.
What is a Humanitarian Device Exemption (HDE)?
The humanitarian device regulations were first established in October 1994. Humanitarian Use Devices (HUDs) are medical devices specially designated by the FDA for use in the treatment of fewer than 4000 patients per year with rare medical conditions.
Intacs corneal implants were approved under a Humanitarian Device Exemption (HDE) by the FDA in July 2004, allowing Intacs to be used for treating keratoconus. Intacs were first designated a Humanitarian Use Device (HUD) by the FDA's Office of Orphan Products Development in August 2003.
Where can I get more information?
Your eye doctor is the best resource for any specific questions you may have regarding this condition. Please also refer to the section related to Seeking More Information or Contacting Addition Technology.
Regular eye examinations are crucial to preserving your eye health and maintaining excellent vision.