Report from GSLS 2024

(Global Specialty Lens Symposium)

Every year, around 600 contact lens specialists from all corners of the world gather in Las Vegas to access the very latest research, establish contacts, and share experiences regarding specialty lenses. We sent our sharpest specialists, Eva Zschüttig Wigh and Åsa Karlsson, across the Atlantic, and they returned with a wealth of new knowledge and inspiration – which, of course, we want to share!

At GSLS, lectures are held in several parallel rooms, and there is an exhibition for the participants. Here is a selection of the knowledge and trends that Eva and Åsa picked up!

Keratoconus

• The latest research on keratoconus shows that the prevalence is higher than previously thought, especially in certain regions.

• It's good to remind carriers of keratoconus not to rub their eyes and to check their eyes often at a young age.

New instruments

• One speaker went through the technology and instruments available for specialty lens fitting, such as topographers, profilometers, etc. Like in the medical technology industry in general, the trend is towards increasingly personalised contact lenses. New instruments provide measurements that enable the manufacture of lenses that fit the eye optimally. This is something we will see more of in the future!

Scleral lenses

• Issues with scleral lenses are not always caused by the lens fit but can be due to other factors, such as material selection based on DK value and wetting angle. The customer may experience a toxic reaction to the lens solution, and eyelid hygiene is also important for successful scleral lens wear. Treating the lens with Hydra-PEG reduces deposits and increases lens comfort.

• There can be a suction effect under a scleral lens, and speakers discussed how this can cause symptoms and how it can be addressed. Midday fogging, for example, can partly be caused by this suction effect, and fenestration on the lens can solve the problems. It's also important to achieve a uniform fluid reservoir and, if possible, avoid unnecessarily high clearance. High sag on the lens requires a larger diameter for proper fitting.

• Debris can be caused by an insufficiently fitted edge/landing zone or can be due to corneal epithelial cells with high turnover rate, with these cells remaining in the fluid reservoir under the lens.

• Regarding debris (fogging), there is a difference between focal debris, consisting of cells accumulated under the lens, and diffuse debris, consisting of lipids. For diffuse debris, partially filling the lens with preservative-free lubricating eye drops may help.

• Studies have shown that there may be a greater need for non-spherical edge on scleral lenses than currently fitted. A study of 140 scleral lens wearers showed that only six percent had a spherical sclera where the lens landed. 29 percent had a toric sclera, and 65 percent had a more asymmetrical sclera.

• Remaining astigmatism in over-refraction may be due to lens decentration or highly irregular cornea creating an uneven fluid reservoir. Optimise the lens landing and central lens fit if possible.

• Higher-Order Aberrations (HOA) were also discussed. A well-fitted lens with a uniform fluid layer reduces HOA. In the USA, some work with HOA-correcting scleral lenses, ordered by measuring HOA using an aberrometer while the lens is on the eye.

Rigid lenses

• Twenty years ago, contact lens guru Nathan Efron predicted that rigid lenses would disappear within 10 years. During the conference, a debate was held between Nathan Efron and Ed Bennett (another big name in rigid lenses), which ended in consensus: Rigid lenses continue to play an important role, and despite being a small part of the contact lens market, the rigid lens is indispensable for some patients.

• The number of rigid lenses has increased with the launch of better scleral lenses. Perhaps corneal lenses will increase with new eye measurement and lens manufacturing technology.

Ortho-K and myopia control

Of course, there was also much discussion about Ortho-K and myopia control.

• What do we consider myopia progression, and how do we follow up? Progression is multifactorial.

• Mark Bullimore talked about a study finding slower axial length growth associated with increased decentration of Ortho-K lenses.

Scientific posters

• One poster in the exhibition described a successful fitting of a two-curved design with reversed geometry for a patient with post-refractive myopia. The lens is of a similar design as our soft lens ML Post Surg. We felt proud that we at Multilens have long been able to offer such a lens!

• Several posters dealt with fitting of soft colored lenses, both cosmetic tinting and filter color successfully used for patients with stroke, achromatopsia, etc.

GSLS Award of Excellence

It felt particularly nice to be Swedish at the conference when Swedish-American Jan Bergmanson received the "GSLS Award of Excellence". He gladly talked with us during breaks and seemed happy to have fellow nationals present!