When the cornea thins and bulges out
Posted Tuesday, January 10 2017 at 18:27
- Keratoconus is a progressive eye disease in which the normally round cornea thins and begins to bulge into a cone-like shape.
- The condition is triggered by overexposure to ultraviolet rays from the sun, excessive eye rubbing, and a history of poorly fitted contact lenses or chronic eye irritation.
A medically proven problem facing users of contact lenses affects the cornea, the curved clear or transparent layer forming the front of an eye.
In the case of one Peter Wambasi, 29, who suffers from keratoconus (thinning of the cornea to the point of blurring vision), his condition cannot be corrected by spectacles but by soft custom contact lenses.
Keratoconus is a progressive eye disease in which the normally round cornea thins and begins to bulge into a cone-like shape. Instead of perceiving light naturally, affected eyes have their cornea deflecting light as it enters the eye on its way to the light-sensitive retina, causing distorted vision.
“The doctors at Lions SightFirst Eye Hospital told me that my condition can only be corrected by corneal crosslinking, a surgery meant to strengthen my corneal tissue to stop it from bulging,” said Peter in an interview.
“After surgery I can only wear special contact lenses — spectacles would not be of much help to me.”
His condition started almost a decade ago but was simply ignored, after all he could still see.
“Keratoconus worsens with time,” said an phthalmologist at the Columbia Africa Hospital, Zelalen Wudineh.
“The condition is triggered by overexposure to ultraviolet rays from the sun, excessive eye rubbing, and a history of poorly fitted contact lenses or chronic eye irritation. It can also affect more than one member of the same family due to its genetic predisposition,” he said.
Dr Wudineh was speaking during an interview at his office in Park Place, Nairobi. He said that due to its nature, treatment for progressive keratoconus is surgery and contact lenses (post- surgery).
Contact lenses are made from flexible soft plastic material to allow free oxygen flow through the eye cornea.
There are of two types, soft and rigid contact lenses, with the latter being more firm with high optics. The rigid contact lenses are approved for overnight wear though you are not supposed to sleep while still wearing them, said Dr Wudineh.
According to a doctor’s prescription, there are disposable contact lenses in the market that can cost you up to Sh70,000 annually if you change them every two weeks. A single buy can cost about Sh2,000.
The worst thing that can happen to a contact lens wearer is an eye infection, he said.
“Eye infections might lead to loss of vision and even brain damage, simply due to poor cleaning of the lenses,” he said.
“You can simply do anything with them but remember to clean them regularly.”
Contact lenses are more superior to glasses and that is why it is highly recommended for sports men and women who have eye discrepancies, said the eye expert.
They are usually prescribed for eye patients with the power of one of their eyes being more than four diopter. A diopter is the unit measurement of refractive power of how far the eye lenses can see.