This issue is teeming with valuable information that may aid you in fitting scleral lenses: step-by-step approaches in the initial fitting of these lenses, avoiding mistakes and complications related to lens wear and multifocal design options.
By all measures, the recent surge in scleral lens use is nothing short of phenomenal. This uptick is easily attributed to the many advantages scleral designs offer and the new materials used for irregular corneas and severe ocular surface disease indications. In addition, success can also be attributed to practitioner education programs offered throughout the world—increasing the number of providers comfortable using these lenses.
The advantages of using scleral lenses are numerous compared with both smaller GP corneal lenses and even soft lens modalities, and include excellent lens centration, exceptional acuity and relatively good comfort. For the most part, there are a only few downsides to these lenses that primarily relate to insertion and removal difficulties, as well as a few nuisance complications such as lens fogging and reduced oxygen flux. Even the most dreaded complication attributed to contact lens wear, microbial keratitis, seems to be rare and is only cited in a few isolated case reports.
A significant concern raised with the surge in scleral lens use is the lack of long-term surveillance on safety data. Even though scleral lenses date back to the early history of contact lenses, their use throughout the past 50 years has been quite limited until recently. So, what are the long-term complications, and will there be any yet-to-be-identified complications with expanded use? Unfortunately, we lack large registries to help answer these important questions with confidence and assure us that there will not be any unexpected findings.
In the Scleral Lenses in Current Ophthalmic Practice (SCOPE) study, the Mayo Clinic Survey Research Center surveyed a large group of practitioners treating more than 80,00 patients to look at key information including complications found in scleral lens wearers.1
The most commonly reported complications (462 patients) were the result of inserting or removing scleral lenses incorrectly. An additional 148 patients developed an eye problem because they used eyecare products that were not recommended by their doctors. The study noted corneal edema or swelling in 385 patients, corneal neovascularization in 238 patients and corneal infections in 70 patients while wearing scleral lenses. Also, two patients experienced graft rejection while wearing scleral lenses.1
Overall, the study reported few complications associated with scleral lens wear, even though these lenses tend to be prescribed for individuals who have some form of ocular pathology.1
Serious complications directly attributed to scleral lens wear appear to be exceedingly rare, and other non-sight threatening complications appear also to be relatively rare. Nevertheless, patients who wear scleral lenses should continue to follow their eyecare provider’s recommendations for lens care products and advice for inserting and removing their lenses, which seem to account for most of the complications reported to date.1
Although the use of scleral lenses is increasing, an ever-important question remains: Should we be moving so quickly to embrace fitting these lenses on regular corneas, rather than just on irregular corneal surfaces or patients with severe ocular surface disease? We’d all like to use these lenses, especially with the introduction of new multifocal designs that makes these lenses another viable option for presbyopia. Only additional follow-up over time will elucidate any new complications related solely to scleral lens fits and fully determine the true prevalence of complications found in its wearers.
In the meantime, proceed with some heedfulness. Scleral lenses remain an important part of any comprehensive contact lens practice, and I suspect that, with time, we will continue to find these lenses to be both reasonably safe and effective.
Until the jury returns a final verdict, continue to screen properly—especially for good endothelial function—and weigh all the options carefully. As with any medical device, ongoing surveillance is wise to continue ensuring both efficacy and safety.
|1. Harthan J, Nau CB, Barr J, et al. Scleral lens prescription and management practices: The SCOPE Study. Eye Contact Lens. 2018;44 (Suppl 1):S228-32.|