MULTIFOCAL LENSES
Bifocals, Multifocals, Monovision What Works Today
Five knowledgeable practitioners share their experiences about fitting presbyopic contact lenses.
By Jennifer A. Barr, BA
Recently, Contact Lens Spectrum interviewed five doctors with experience and perspective on presbyopic contact lenses: Douglas Benoit, OD, FAAO, from Concord, NH, Rex Ghormley, OD, FAAO, from St. Louis, Thomas Quinn, OD, MS, FAAO, from Athens, OH, David Hansen, OD, FAAO, from Des Moines, IA, and Don Ezekiel, Dip Opt. (WA), DCLP, FACLP, FAAO, FCLSA, from Perth, Australia. They discussed fitting strategies, their first choice lenses and brief case histories of presbyopic contact lens patients.
Multifocals vs. Monovision
Contact Lens Spectrum: Do you use multifocal contact lenses first or monovision?
Doug Benoit, OD: I generally try bifocal/multifocal contact lenses before monovision unless the patient is a very early presbyope (+0.75D or less).
David Hansen, OD: I use multifocal contact lenses first. I rarely use monovision anymore because we have great multifocal options in hydrogel and GP materials.
Rex Ghormley, OD: I usually start with monovision for adds up to +1.25D. With higher adds, I begin to consider a bifocal. The new +1.00D add design by CooperVision, Frequency 55 Multifocal, may let me start some lower add patients directly with a bifocal. In theory we should all start with a bifocal.
Tom Quinn, OD, MS: I aim to provide my lens-wearing patients with the best, most natural vision possible. Binocular vision best achieves this, so multifocal lenses are my first choice. I believe successful multifocal wearers have a better quality of visual life than monovision wearers. Monovision is still a technique I use, but instead of my first choice, as it was a decade ago, it is now my last-ditch effort if multifocals are not successful.
Lenses for Presbyopia
CLS: What are your top multifocal or bifocal lenses, both soft and GP?
Dr. Benoit: I prefer Essential Xtra (Blanchard) for a GP aspheric center distance design, Solutions (X-Cel) or Metro-Seg (Metro Optics) for translating GP designs, Acuvue Bifocal (Vistakon) for a soft center distance design and Focus Progressives (CIBA) and Quattro (Blanchard) for soft center near designs.
Dr. Hansen: My soft bifocal choices include Frequency 55 Multifocal, Bicon (Westcon) in Horizon 55 material (spherical and toric), then Acuvue Bifocal and CIBA Focus Progressives. My GP choices are VFL 3 aspheric (Conforma Contact Lenses), Annular translating Decentered DeCarle (Conforma), Solutions and Presbylite II (Lens Dynamics).
Dr. Ghormley: My soft lens favorites are Frequency 55 Multifocal, SofLens Multifocal (Bausch & Lomb) and Additions (Ocular Sciences). My GP favorites are Lifestyle GP Multifocal (The Lifestyle GP Company), UltraVue 2000 (OptiCentre Lab) and Presbylite.
Dr. Quinn: My first choice in soft multifocals is the Acuvue Bifocal. It gives me an extended wear option and I feel comfortable troubleshooting with it. My second choice is the Frequency 55 Multifocal, which is a great troubleshooter when I have problems achieving desired vision with the Acuvue Bifocal. I also find it is a very easy lens to handle, which has saved me with a few particularly novice wearers who became frustrated handling the Acuvue Bifocal. My third choice in soft multifocals is the SofLens Multifocal. This is my first choice for patients with a near plano distance prescription. The "softer" multifocal optics seem to disturb distance vision less.
I lean toward a GP multifocal when a patient is a current GP wearer or has astigmatism equal to or greater than 0.75D, especially if the cylinder is in the dominant eye. My first choice GP multifocal is the Essential GP. It offers a series of adds that provides easy adjustment of the patient's prescription as he progress into presbyopia. As presbyopia increases, I commonly increase to the next stronger add power in the non-dominant eye only. If I don't succeed with the Essential GP, my second simultaneous vision lens choice is NewView2 (Hydrokinetics) annular design lens. If I need to try a translating design, usually for high near demand, my first choice is the Solutions Bifocal. It is one of the most comfortable translating designs, and its fitting approach is very straightforward. My next choice for translating designs is the Tangent Streak Bifocal (Fused Kontacts), which is very thick but stable on most eyes.
Fitting Presbyopes
CLS: Which lenses are best for early vs. late presbyopia, and for myopes vs. hyperopes?
Dr. Benoit: I prefer the Essential Xtra for patients with corneal cylinder and/or moderate visual demands at all distances. The Acuvue Bifocal is good for patients who cannot tolerate GP lenses, myopes and people with higher distance needs. A center near design like Focus Progressives or Quattro is better for hyperopes or people with higher near demands.
Dr. Hansen: VFL 3 has served me with all presbyopes, children's binocular vision problems and hyperopes, using the Super Add design.
Dr. Ghormley, OD: Simultaneous vision bifocals are best for low add powers and patients who work on a computer. But many times it is difficult to achieve a high add in these designs. A translating bifocal design is best for high add powers, but not always satisfactory for computer users. Also, the thicker translating lens can sometimes cause lens awareness issues. Occasionally we use modified monovision with a simultaneous vision bifocal and overplus the non-dominant eye for high add patients.
Dr. Quinn: To me the ideal multifocal patient is around 4.00D needing a +1.00D add. Less myopic patients are accustomed to reading without their correction and want their contact lens-corrected near vision to mimic what they enjoy during the uncorrected condition.
Counter to what I initially anticipated, I find hyperopes tend to be more challenging. I have somewhat greater success with the Frequency 55 Multifocal with this population. The higher the add, the greater the potential for the near portion to interfere with the distance vision, so I always prefer a low presbyope. However, you can fit higher presbyopes very successfully, but you must employ unequal adds to achieve an acceptable balance between distance and near vision.
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Recent Bifocal and Multifocal Contact Lens Launches |
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CLS: Please describe a brief case history of a recent patient.
Dr. Benoit: I recently saw a PK, 49-year-old female who wore soft toric contact lens with readers over them, but didn't like this arrangement. We tried monovision, but the patient could not adapt. Her previous doctor said bifocals did not work. Her prescription was 2.50 1.25 x 180 OD, 2.25 1.00 x 175 OS, with an add of +1.50D OU, OD dominant. Her Ks were 43.50/44.75 @ 90, 43.50/44.25 @ 90. I ordered Essential Xtra 7.70mm base curve OU, 9.50mm diameter, OD 2.75 Series II, OS 2.50 Series II. She reported good lens comfort and she has no dryness issues. VA was 20/20 OD, OS, OU at distance and near.
Dr. Quinn: I had a 48-year-old, +1.50D hyperope wearing Bausch & Lomb Occasions Multifocal who presented with complaints of poor near vision. I refit her with the Frequency 55 Multifocal, applying a center-distance D lens to the dominant eye and center-near N lens to the non-dominant eye. The patient returned a week later still unhappy with her vision. Testing showed better vision in the dominant eye, as expected, but also better near vision in this eye. I then fit the patient with a center-distance lens on each eye, which provided her with the desired visual performance.
CLS: How would you fit this patient? She's a 55-year-old magistrate who looks far away at juries in downgaze and is a hockey fan. She hates eye exams and all glasses. She wears OS sphere and OD aspheric multifocal lenses. She has put off getting lenses for better near vision and cannot compromise distance vision. She reads legal briefs, of course.
Dr. Hansen: I would consider judge Frequency 55 Multifocal or C*Vue (Unilens) soft lenses or VFL 3 Super Add lenses. These options would accommodate the distance and far visual acuities. I recommend these lenses provided that the patient's pupillary sizes and corneal measurements do not reveal any surprises. The VFL 3 GP would probably provide the best acuity considering that most court rooms have high overhead lighting with no direct lighting on the legal documents.
Jennifer Barr is a freelance writer based in Dublin, OH.
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Multifocal Lens Fitting Pearls |
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A 0.25D change in power in either eye can significantly impact near and distance vision
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Patients with good high contrast visual acuity with multifocal contact lenses may fail, and patients with poor vision with these lenses may succeed
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Let the patient try a "real world" test with diagnostic lenses on. Have him look out a window, read a magazine in the reception area or even go back to work and return for a follow-up
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Tell the patient that the goal with multifocal lenses is to satisfy "most of his visual needs, most of the time"
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Be patient and persistent to maximize your and your patient's success
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Try telephone progress checks for troubleshooting
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Push the plus and don't overminus and underprescribe the add (in all but alternating vision lenses)
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Use normal room illumination, not too high or too low illumination, when over-refracting
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Use trial lenses or flippers, not the phoropter, to over-refract
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For multifocal contact lenses that are designed for near in one eye and distance in the other, consider trying two near or two distance lenses.
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Triton Bifocal Update |
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The Triton Translating Soft Bifocal lens has an alternating vision design. Translating bifocal lenses tend to be stable on the eye, which allows you to incorporate the patient's full prescription, including the full astigmatic correction at the precise axis in the lens.
Because we were involved in the design and development of the Triton lens, we became aware of problems that practitioners were having fitting the lens. Although we were getting good patient results, we needed to make minor modifications to the lens design and to simplify the fitting procedures.
We made a small design change to overcome initial lens awareness. We found that lens stability decreased when the difference between the horizontal and the vertical meridians increased. Whereas we initially designed all lenses with a constant a segment positioned 0.5mm below the center of the lens, we have altered the lens design to have a constant horizontal and vertical lens size. Depending on the findings using the fitting set, we vary the segment position on the lens accordingly. This has resulted in a stable lens on the eye, which provides uncompromised vision.
Patient LB is a long-time, custom-made, soft contact lens wearer. Patient's Rx:
OD 4.25 / 0.75 axis 160 OS 4.50D sphere
Add +1.50D OU.
K readings OD 41.25 /42.25 x 170 OS 41.75/42.50 x 10
From the Triton fitting set, we determined that a lens with a vertical diameter of 13.5mm demonstrated the correct fitting for the segment setting lens (the marker dots in line with the center of the patient's pupil). This placed the segment position at 12.4mm below the center of the lens.
Initial lens fitted:
OD 8.80 / 13.5 / 12.40 / 4.25 / 0.75 x 170 Add +1.25 sphere
OS 8.80 / 13.5 / 12.40 / 4.50 sphere Add +1.75D sphere
On delivery, the lenses were unstable and uncomfortable.
We redesigned the lenses with diameters of 15.0mm/13.4mm with the segment positioned 2.0mm below center. This gave the patient 20/20 vision at far and N5 at near and all day comfort.