Scleral contact lenses

Patients with Keratoconus or other corneal diseases can often just not get spectacles or contact lenses that they can see clearly with.

Higher-order aberrations (HOAs), which cannot be corrected by spectacles, are more subtle and complex refractive errors than near-sightedness, farsightedness and astigmatism. These optical and anatomical irregularities can cause difficulty seeing at night, glare, halos, blurring, starburst patterns, distorted images or double vision.

Speciality contact lenses like scleral lenses can effectively neutralize many of these induced aberrations by masking the irregularities on the front part of the cornea. There is an impressive body of evidence proving the success of scleral contact lenses for visual rehabilitation of eyes with corneal and external ocular disease.

The success of scleral contact lenses stems from three factors:

  1. The retention of a tear reservoir under the contact lens. This fluid protects the abnormal surface of the cornea.
  2. Protection of the surface  of the eye from the lid margins, lashes, and the external environment.
  3. A smooth surface to bend the light correctly focussing light on the nerve layer of the eye and bringing the image into focus

In spite of their potential to improve difficult-to-treat ocular surface conditions, scleral contact lenses remain underutilized. This is due to the fact that it requires specialised skill to fit and fitting can be quite time consuming and requires multiple visits. This leads to higher costs than regular contact lenses.