Scleral contact lenses are not only prescribed for people living with keratoconus. Around 74 percent are prescribed due to any type of corneal disorder causing discomfort in utilizing traditional contact lenses, but 16 percent are prescribed for ocular surface disease – and 10 percent for uncomplicated refractive error – according to an article in Clinical Optometry. If you have keratoconus and find RGP contact lenses uncomfortable due to cornea pain and/or persistent “dry eyes”, scleral contact lenses may be a better corrective eyewear choice for you.
The following describes scleral contact lenses (along with the difference between scleral and RGP lenses), and three tips for adjusting to wearing these larger-sized contact lenses.
Comparing Scleral Contact Lenses to RGP Contact Lenses
Due to the combination of myopia and astigmatism that is typical in keratoconus, “hard” (RGP) contact lenses rather than “soft” lenses are usually prescribed for vision correction. However, cornea pain and “dry eye” syndrome – that often accompany keratoconus – can make wearing either RGP or “soft” contact lenses difficult for more than one or two hours. This is because both RGP and “soft” contact lenses rest on the cornea. In contrast, scleral contact lenses rest on the white of the eye termed the sclera. Additionally, scleral contact lenses include a fluid reservoir that can help to reduce the sensation of “dry eyes”.
Scleral contact lenses are basically made of the same material as RGP contact lenses. Yet, the need to precisely-fit the scleral contact lens over both the cornea and sclera means that the fitting requires more measurements than for RGP lenses. Therefore, the “fitting” process tends to take more time (in hours) than for RGP lenses. One method frequently utilized to fit scleral lenses is high-resolution optical coherence tomography.
Below are three common differences experienced by keratoconus-afflicted people in using scleral contact lenses (as opposed to RGP contact lenses):
- Insertion of a scleral contact lens may require utilization of an applicator as opposed to insertion of a RGP contact lens.
- Removal of a scleral contact lens may be more difficult than removal of a RGP contact lens.
- Scleral contact lenses require use of a different cleaning solution (and different storage solution) than used with RGP contact lenses.
Tip Number 1 for Using Scleral Contact Lenses
If you have keratoconus and have never before utilized contact lenses, allot yourself ample time to adapt to inserting (and removing) scleral contact lenses. Learning to insert the scleral lens so that it is positioned correctly in your eye can take both time and practice. This is equally true of the lens removal process. However, the improvement in your vision (and decrease in experiencing “dry eyes”) will soon outweigh the steep learning-curve to correctly insert/remove your new contact lenses.
Tip Number 2 for Using Scleral Contact Lenses
According to an article in the Journal of Contact Lens Research and Science, scleral contact lenses should be cleaned by rubbing for a minimum of 15 seconds and rinsing prior to overnight storage. This is because – not only can bacteria and debris attach to the lens (similar to a RGP lens) – but bacteria and debris can lodge in the fluid-containing reservoir. Tap water should never be used for cleaning contact lenses (including scleral contact lenses) due to the risk of contracting Acanthamoeba keratitis, per an article published in Ophthalmology.
Since keratoconus-afflicted people are at higher risk of permanent cornea damage consequent to infection, it is even more crucial that you properly clean and disinfect your scleral contact lenses using only solutions designed for scleral lens cleaning and disinfection.
Tip Number 3 for Using Scleral Contact Lenses
Do not wear your scleral contact lenses in a swimming pool, sauna, or the shower. Doing so risks your losing the contact lenses, which can wash out of your eyes. Likewise, it is important not to go to sleep for the night without removing your scleral contact lenses. This can also lead to a cornea infection (as well as worsen “dry eye” symptoms).
The Precision Keratoconus Center can help you in learning more about scleral contact lenses, as well as other contact lenses and treatments for people afflicted with keratoconus.