Tips for fitting pupil-optimized multifocal contact lenses
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Fitting the aging eye with contact lenses can be a challenge.
In addition to losing our focusing ability as our eyes age, studies show that tear film break-up time drops by 50% by age 50 (Mostafa et al.), and light scatter increases by 50% by age 60 (Van Den Berg et al.).
Multifocal soft contact lenses not only pose a challenge to an already compromised tear film but can also contribute to an increase in halos, ghosting and or glare. Despite all of these challenges, 94% of our presbyopic contact lens wearers expect to be able to continue to enjoy the freedom and vision with contact lenses as their eyes age (IPSOS global incidence tracker).
Multifocal contact lenses with a pupil-optimized design can help overcome these challenges because they factor in age-related pupil changes with sphere and add power to create 183 different power profiles, balancing distance, intermediate and near vision.
Here are my tips for optimum success when fitting these lenses:
- Get an accurate refraction and avoid over-minusing by using a red/green balance. Start with a fresh refraction and a monocular red/green balance. After your subjective refraction, add +0.50 D OU, show a block of letters and slide in the red/green filter. The addition of +0.50 D OU should make the red side of the chart “pop” darker or clearer. Now decrease the plus until you achieve balance; if balance can’t be achieved then leave them at the last red. This test should result in the ideal prescription. Repeat this process for the left eye.
- Understand the two types of eye dominance. I was always accustomed to sighting dominance, where we determine a patient’s aiming eye. This is how most of us traditionally learned about dominance. Sensory dominance simulates adding disparity by determining which eye has the greatest sensitivity to plus defocus, thus correlating well with multifocal lenses. In about 20% to 40% of cases, this eye is different from the sight-dominant eye (Lopes-Ferreira et al.). We need to determine sensory dominance for fitting success. I test sensory dominance just after my refraction and red-green balance. With the patient looking at a 20/25 target, I take a +1.50 D loose lens and hold it in front of the right eye and then move it over to the left eye. The eye that is most sensitive to the blur is the sensory dominant eye. This eye is most sensitive to plus defocus, so to achieve the best distance vision, we never want to add disparity to that eye.
- Use the lens calculator to help you find the best lens. For pupil-optimized lenses we can use a simple web-based calculator that follows the fit guide. Whether you are a seasoned multifocal lens fitter or new to it, this calculator is an amazing resource to simplify your process and increase your success and confidence in fitting and prescribing multifocal contact lenses. Remember to use the functional add, which is the minimum add someone needs to read at a specific working distance. I often go with the age-related recommended add powers. Once you put in the data, the calculator will do all the math (spherical equivalent, vertex), and it will give you the parameters for the best pair of initial contact lenses. It also gives you distance and near enhancement options. I have met many doctors who have gone from a 50% to 60% success rate to at least 90% with the first lens that is suggested by the calculator. The calculator provides these results for all the pupil-optimized products: the Acuvue 1-Day Moist Multifocal, the Acuvue Oasys 2-week Multifocal and Acuvue Oasys Max 1-Day Multifocal (Johnson & Johnson Vision), which the company reports has 60% blue light filtering and TearStable Technology to improve quality of vision and comfort throughout the day and into the evening for our patients.
- Consider working with a scribe. I’m always quick to embrace efficiencies that help to maintain patient flow, which is why I use a scribe during contact lens fittings. My scribe often uses the online calculator to determine the first lens parameters and assists the patient with insertion while I attend to another patient. By the time I return, the patient is seeing well.
- Make adjustments based on the patient’s needs and feedback. After a 10-minute settling time, I make an enhancement to distance or near vision if my patient needs it, but most often, I send my patient home with the first diagnostic lenses. With this method, I find 90% of my patients are happy with the first lens.
By utilizing the appropriate fitting method, many practitioners are able to overcome the challenges of multifocal contact lenses, and patients find themselves in comfortable lenses that meet their vision needs.
References:
- Brito P, et al. J Cataract Refract Surg. 2015;doi:10.1016/j.jcrs.2014.07.033.
- Chu BS, et al. Eye Contact Lens. 2009;doi:10.1097/ICL.0b013e3181a1435e.
- Chu BS, et al. Invest Ophthalmol Vis Sci. 2010;doi:10.1167/iovs.10-5154.
- IPSOS global incidence tracker, retail outlet consumption data and national census population data in US. 2018.
- Johnson & Johnson Vision launches new contact lens innovation to help meet the needs of digitally intense lifestyles: Acuvue Oasys Max 1-Day. https://www.jjvision.com/press-release/johnson-johnson-vision-launches-new-contact-lens-innovation-help-meet-needs-digitally. Published Sept. 12, 2022.
- Lopes-Ferreira D, et al. Biomed Res Int. 2013;doi:10.1155/2013/238943.
- Mostafa Y, et al. Egyptian Journal of Medical Research. 2021;doi:10.21608/EJMR.2021.174931.
- Papas EB, et al. Eye Contact Lens. 2009;doi:10.1097/ICL.0b013e3181a20361.
- Van Den Berg TJ, et al. Am J Ophthalmol. 2007;doi:10.1016/j.ajo.2007.05.037.
For more information:
Heidi Pham-Murphy, OD, is president at Visions Optometry in Sacramento, California; vice president at EyeDesigns Optometry in San Rafael, California; and clinical director of Opening Eyes for Special Olympics Northern California and Nevada.
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