Contact Lens Care & Compliance
Choosing a Large Scleral GP Lens Storage Case
BY MICHAEL A. WARD, MMSC, FAAO
Ponder this: Your 58-year-old patient has granular corneal dystrophy with symptoms of decreasing vision, glare, photophobia, and occasional sharp pain. You decide to fit her with a scleral lens to relieve her symptoms and improve her vision. During diagnostic lens fitting, you determine the proper central sagittal depth, limbal clearance, and haptic design parameters and decide on an 18mm diameter scleral GP lens.
As you write the scleral lens order, you begin thinking about appropriate lens care instructions. Facts and considerations include that the patient is new to contact lens wear and will need complete instructions. Should you choose a standard GP chemical lens care regimen, possibly a soft lens care system (off-label), or a peroxide system?
Suppose that you generally prefer peroxide systems because they offer excellent disinfection without preservatives. However, there is not a commercially available peroxide-based system designed to accommodate the 18mm scleral lens. PeroxiClear (Bausch + Lomb) and Clear Care (Alcon) can only accommodate lenses up to about 16.5mm. There is one very large lens case available online (Prose disinfection case, The Dry Eye Company, Figure 1), but it is not part of a commercially available system. The Prose lens holder cage has a post where a neutralizing disc may be added. The platinum catalytic disc that comes packaged with Clear Care (which is not available to purchase by itself) is required to neutralize the peroxide solution in the Prose case (Boston Foundation for Sight, 2014).
Figure 1. (left to right) Prose case, PeroxiClear case, Clear Care Case. The Prose case requires three times the solution volume as the other two cases.
Then again, does your patient really need to neutralize the GP lens that has soaked in peroxide? Why not use the peroxide solution in a regular deep-well, screw-cap lens case? Because GP lenses don’t absorb the storage solution, patients can safely rinse peroxides or chemical disinfectants from the lens surfaces with a generous morning sterile saline rinse (Gromacki and Ward, 2013).
Or, why not just use a current-generation hydrogel multipurpose solution (MPS)? Certainly MPSs could adequately disinfect the GP lens, but they are not approved by the U.S. Food and Drug Administration (FDA) for GP lens disinfection, and they lack sufficient GP surface cleaning capabilities. The surface cleaning problem can be solved by adding a strong alcohol-based daily cleaner or a strong surfactant/abrasive daily cleaner and then soak the lens overnight in a soft lens MPS. It’s important to instruct patients to rinse the lenses thoroughly after using daily cleaners so no chemical residue remains.
Contact lens cases are Class II medical devices and require a 510K clearance from the FDA before marketing (Sindt, 2012). It sure would be nice to have a scleral lens-sized peroxide care system. I hope that one of our industry manufacturers (or an entrepreneur) creates and markets a reasonably sized lens storage case to accommodate scleral lenses that can be used with peroxide disinfection systems. Thanking you in advance. CLS
For references, please visit www.clspectrum.com/references and click on document #231.
Mr. Ward is an instructor in ophthalmology at Emory University School of Medicine and director, Emory Contact Lens Service. You can reach him at firstname.lastname@example.org.