Contact Lens Design & Materials
Three Mainstream Myths About Multifocal Contact Lenses
BY DAVID L. KADING, OD, FAAO
If I told you that I tried vegetables once and hated them so I never tried them again, you might think I was crazy. And yet, we often form our perceptions of multifocals after just a few tries and a few mild failures. Multifocal lenses always work, we just have to define what success is ahead of time. Many practitioners have justified moving away from multifocal lenses for one of the following reasons: 1) I tried a multifocal on my patient and it didn’t work; 2) My patients do better in monovision; or 3) I followed the fitting guide and didn’t succeed. Our industry partners want us to be successful with their lenses, and they work hard to support us. Here, I dispel three of the most common myths about multifocal lenses.
1. One lens design will work for all of your patients.
The success of each company’s multifocal lenses reveals that every single design out there has a place for certain patients. However, some companies boast increased market share over others. This then begs the question: Does a specific company have more market share because its design or sales force is better, or because the lens is easier to fit?
Consider this hypothetical: If we lost all of the current lens designs except one, could we still be successful? I would argue “yes.” We would learn what makes us successful with that design, begin fitting it to meet those expectations, and we would all enjoy success to a degree. I must concede, however, that the one choice may be less successful than what we have now with the near endless options of multifocal designs.
2. Patients prefer monovision.
An argument for monovision is that patients do not mind the difference. Richdale et al (2006) showed that when patients wore both multifocals and monovision—and then were given the choice of their preference—the vast majority chose the success they achieved with multifocals.
In many cases, well-adapted monovision patients desiring more range in their vision may need adaptation time, and the fitting guide may need to be modified, to gain success.
3. I can always follow the fitting guide for success.
Fitting guides are exactly that—guides. Companies spend millions of dollars on research into how to be successful with their lenses because they want you to succeed. However, the guides are intended to work for patients who fit into the majority of the bell-shaped curve. They oftentimes leave off the trailing ends of the particular patient population.
Now it is time to venture into uncharted territory. For example, you may have a patient who is a recreational sniper and needs to read the wind gauge at his fingertips, or a scientist who studies ant saliva for a living yet drives 40 miles to work every day. These patients were not included in the studies, but they show up at our doorstep looking for options.
In these cases, use your knowledge of optics, the designs, and your patients. But for most people, the guide will work.
Keep in mind that multifocal vision is not single vision. It has variety and variability. It isn’t perfect, but neither is single vision with readers or monovision. All of these options have upsides and downsides. Don’t rob your patient of this lens possibility because of the mainstream myths; instead, become a myth buster. CLS
For references, please visit www.clspectrum.com/references and click on document #234.
Dr. Kading owns the Specialty Dry Eye and Contact Lens Center in Seattle. He is the co-owner of Optometric Insights with Dr. Brujic. He has received honoraria for consulting, performing research, speaking, and/or writing from Alcon Laboratories, Allergan, Bausch + Lomb, Biotissue, Contamac, Essilor, Nicox, Oculus, RPS Detectors, TearScience, Valley Contax, and ZeaVision. Follow him on Twitter @davekading.