Keratoconus

Eye disease, or “KC,” is a non-inflammatory eye condition in which the round dome-shaped cornea progressively thins, causing a cone-like bulge.  As the cornea becomes more irregular in shape, there is an increase in nearsightedness and irregular astigmatism, which results in distortion, blurred vision, glare and light sensitivity. The actual incidence of KC is not known but it has been estimated to occur in 1 out of every 2,000 people in the general population. Keratoconus can occur in one or both eyes and often begins during a person’s teens or early 20s, with a higher prevalence in males.

Causes

The exact cause of keratoconus is unknown.It is estimated that there is less than a one in ten chance that a patient will inherit keratoconus from a family member. Keratoconus patients have a tendency of extensive eye rubbing; allergies that cause eye itching and irritation that leads to more eye rubbing; and atopic diseases such as hay fever, eczema, asthma, and food allergies.   kc pic  

Photo Credit: http://eye-clarity.com/

Symptoms

The earliest signs of keratoconus are usually blurred vision, frequent changes in eyeglass prescription, or vision that cannot be corrected with glasses. Other symptoms include:

  • Increased light sensitivity
  • Difficulty driving at night
  • A halo around lights and ghosting (especially at night)
  • Eye strain
  • Headaches and general eye pain
  • Eye irritation, excessive eye rubbing
 

Diagnosis

Our keratoconus Optometrists in Calgary are able to diagnose keratoconus during your eye exam through a slit-lamp examination, keratometry readings that measure the curvature of the corneas, corneal topography—which involves a computerized instrument that makes a 3D map of the cornea—and retinoscopy—atechnique used to obtain an objective measurement of a patient’s prescription and observe the reflection or reflexof the patient’s retina.

Keratoconus Treatment Options

If glasses are unable to correct a patient’s vision or a patient would like to supplement glasses, there are numerous keratoconus contact lensesoptions available to provide significant vision improvement.

  • Rigid gas permeable contact lenses (RGP) are made of an oxygen-permeable, rigid material that is smaller than the size of the corneal diameter. Their rigid property helps to mask corneal irregularity and provide clearer vision.
  • Contact hybrid lenses are designed with a rigid gas-permeable lens center and a soft lens skirt to help lens centration and provide added comfort when wearing the lens.
  • Scleral lenses are larger diameter, rigid, gas-permeable lenses that vault over the entire cornea without touching the corneal surface.
 

Corneal Collagen Crosslinking with Riboflavin (CXL)

CXL is not a cure for keratoconus, but rather a treatment option to arrest progression and prevent further deterioration of vision. The keratoconus cross-linking treatment works by increasing the collagen crosslinks or anchors within the cornea to prevent the cornea from bulging out and becoming steep and irregular. During the treatment, riboflavin drops are applied to the cornea and activated by ultraviolet light. This process has been shown in clinical studies to increase the amount of collagen corneal cross-linking,therefore strengthening the cornea. Glasses and/or contact lenses will be needed following the cross-linking treatment.

Intacs

Intacs are a thin, plastic, semi-circular ring that is inserted into the mid-layer of the cornea in order to flatten the cornea, changing the shape and location of the cone. Intacs alter and strengthen the cornea, eliminating some or all of the irregularities caused by keratoconus to help improve vision. Glasses and/or contact lenses may still be needed post-treatment.

Corneal Transplants

15-20% of those with keratoconus ultimately require an eye surgery for keratoconus—usually a corneal transplant surgery, where a damaged or diseased cornea is replaced by a donated corneal tissue or graft. A corneal transplant is an effective type of laser treatment for keratoconus.

If you have Keratoconus or are concerned you may have it, book an appointment for an eye exam today at our Calgary location. Our optometrists are able to help diagnose and provide the best treatment for keratoconus that will best suit your needs. We also work closely with local corneal Ophthalmologists in Calgary to co-manage keratoconus.