Scleral lenses are lathed in high- or hyper-Dk fluorosilicone acrylate materials, which maximize oxygen permeability but are also prone to lipid deposits (Bennett and Henry, 2013). Scleral lens care can be a source of ongoing confusion for patients, especially with the necessity of an added filling solution. Practitioners can minimize corneal complications by emphasizing the importance of using proper cleaning, soaking, and filling solutions at every visit for all patients.

Cleaning

Whether patients choose to use a one- or a two-bottle care system, emphasize the importance of digitally rubbing and rinsing lenses prior to soaking. This helps remove deposits and prepares lenses for overnight disinfection. Abrasive cleaners with silica gel beads are milky in color and should not be used with hyper-Dk materials, which are prone to surface scratches, or with lenses that have a polyethylene glycol (PEG)-based coating.

Alcohol-based cleaners are exceptional at removing lipids (Bennett and Henry, 2020), while periodic enzymatic cleaners can help heavy protein depositors; both, however, will prematurely deteriorate a PEG-based coating. One-bottle care systems may be a convenient option for patients who have minimal deposits, while hydrogen peroxide-based cleaners work well for those who have preservative sensitivities; both are often approved for use with PEG-coated scleral lenses.

Soaking

Storing scleral lenses overnight for the minimum recommended time of four-to-six hours, depending on the lens care system used, helps ensure bactericidal and bacteriostatic effectivity. Aside from hydrogen peroxide-based systems, all soaking solutions are heavily preserved and may induce corneal toxicity when trapped in the scleral lens tear reservoir. Rinsing thoroughly with saline prior to lens application may improve patient comfort and prevent corneal toxicity (Epstein et al, 2009). Gently remind patients to never rinse with tap water to mitigate risks of Acanthamoeba keratitis.

Filling

Scleral lenses move minimally with little tear exchange once fully settled (Skidmore et al, 2019). Any filling solution used should be sterile and preservative-free. Buffers may be incorporated to maintain a nearly neutral pH to mimic the tear film; dry eye patients have reported greater comfort when filling their scleral lenses with a buffered solution (Caroline and André, 2019). There is a wide range of pH among commercially available filling solutions; sodium chloride inhalation vials (off-label) exhibited the largest standard deviation and the lowest pH (Caroline and André, 2019; Dahms, 2017; Yeung, 2017).

Recent research shows that multidose preservative-free (MDPF) saline (off-label) bottles often lose sterility shortly after opening (Jeong et al, 2021). Nevertheless, they continue to be widely used among scleral lens wearers, with a surprisingly low rate of microbial keratitis (MK). Consider single-use vials for those who have compromised corneas and are at greater risk of MK.

Filling solutions containing electrolytes to mimic the tear film are available; some of my patients have experienced improved comfort and decreased midday fogging. Finding a solution combination that works for a given patient may require a bit of trial and error; provide ample samples of each to ensure that patients find their “cocktail” of choice. CLS

For references, please visit www.clspectrum.com/references and click on document #309.