GP insights
Clinical Pearls From the Global Specialty Lens Symposium
BY EDWARD S. BENNETT, OD, MSED
The annual Global Specialty Lens Symposium (GSLS), held Jan. 28 to 31 in Las Vegas, was once again one of the finest contact lens meetings in the world. Greg Nixon, OD, FAAO, will provide a comprehensive overview of this meeting in next month's issue, but I wanted to share a few of the many clinical pearls that I gained.
Seven GSLS Clinical Pearls
1. New Lens Designs and Their Applications A total of 12 breakout sessions allowed attendees to choose among such topics as large-diameter GP lenses and their applications, new generation hybrid designs, and recently introduced GP multifocal designs.
2. Incidence of Microbial Keratitis (MK) in Orthokeratology Helen Swarbrick, PhD, Msc, BscOpt, communicated the most recent information from the work she has done with Kathleen Watt on MK incidence. They have recorded 129 documented cases of MK from 2001 to 2008 (only six in the United States) with the primary causative organisms being Pseudomonas aeruginosa (49 cases) and Acanthamoeba (42 cases). Mark Bullimore, MCOptom, PhD, reported on a retrospective study of 200 randomly selected practitioners and found an estimated incidence of 7.7 MK events per 10,000 years of lens wear or similar to that previously reported with other overnight lens wear modalities.
3. Corneoscleral Lens Applications Although this topic emphasized irregular cornea management, Jason Jedlicka, OD, has found that corneoscleral lenses (13.0mm to 15.5mm in diameter) are not just for irregular corneas anymore. Standard refractive error patients are excellent candidates, and such lenses are recommended to solve the comfort, centration, vision, and stability issues that can result with other GP or soft lenses.
4. Scleral Lenses for Severe Dry Eye Michael Lipson, OD, FAAO, discussed a series of seven cases of chronic Graft Versus Host Disease. Scleral lens wear improved the quality of life in all of these patients. They were able to wear their lenses for an average of nine hours per day (ranging from seven to 14 hours), and signs and symptoms of severe dry eye improved significantly.
5. Achieving Good GP Lens Centration in Highly Irregular Post-Graft Corneas Paul Rose, OD, discussed multiple piggyback cases in which changing from a +0.50D to a +3.50D silicone hydrogel lens power improved the centration of the GP lens. He also indicated that for every 1.00D increase in soft lens power, a corresponding 0.15mm steeper GP base curve should be used.
6. Advancements in Hybrid Technology Barry Eiden, OD, FAAO, discussed ClearKone (SynergEyes), which has a new hybrid skirt design that lands inside the limbus and extends onto the sclera. It also has optics that tend to center over the visual axis despite the location of the cone and it tends to vault the majority of ectasias, minimizing any areas of bearing. He also indicated that coming soon will be a more flexure-resistant center GP zone, a silicone-hydrogel skirt, and a modified lens geometry for better lens movement and removal.
7. Managing Contact Lens Intolerance with Testosterone Cream In one of the most interesting free papers, Charles Conner, OD, PhD, presented his research on the application of testosterone cream to the upper and lower eyelids in post-meno-pausal females experiencing eye dryness. The application of this cream significantly increased tear breakup time and Schirmer values. More than 90 percent of the patients exhibited an increased wearing time with their contact lenses, with 40 percent exhibiting an increase of, at minimum, eight hours per day. CLS
Dr. Bennett is an associate professor of optometry at the University of Missouri-St. Louis and is executive director of the GP Lens Institute.