A Shift in Presbyopia
A new study compares two methods of managing this
By Lee E. Rigel, OD, FAAO, Rob Davis, OD, FAAO, John Schachet, OD, FAAO
and Paul Klein, OD, FAAO
emerging presbyope in today's society is markedly different than that of 20
years ago. Many of today's patients are long-time soft lens wearers and expect
to continue to experience the comfort and convenience of soft lens wear as their
vision needs evolve over time. These same patients are busy, active adults who
have high expectations for their vision and low tolerance for discomfort or
Unfortunately, as presbyopia
evolves, the surface of the eye becomes dryer. To aggravate this situation, many
presbyopes also take medications that have dry eye symptoms as side effects.
Meeting the complex needs of this patient demographic presents a challenge that
While monovision has
been successful in meeting the needs of many presbyopic patients, this solution
contains many flaws and isn't the most academic approach for addressing the
visual needs of presbyopes. "Monovision has been successful, but is still
lacking in a few important areas," says John Schachet, OD, FAAO. This article
will look at the multifocal approach to managing presbyopia.
"We have just one eye to meet distance vision needs.
With a multifocal lens, we get some near vision from the distance eye and some
distance vision for the near eye. That can make a critical difference for a
patient," says Dr. Schachet.
Safety is one
example he cites. "Let's say a monovision patient is driving down the road with
the sunroof down and something flies into his distance lens. He's in real
trouble for at least a moment, and that momentary disturbance is just long
enough for something bad to happen. With a multifocal lens, at least the patient
still has some distance vision from his other eye during that critical moment."
Rob Davis, OD, FAAO, concurs. "Everyone in our
practice uses the bifocal design as their lens of choice," he says. "I find that
there's just too much separation with monovision. The prescription differences
with bifocal lenses aren't as drastic between the eyes, which makes it easier
for patients to adapt."
Go Head to Head
A recent evaluation of
two leading multifocal lenses revealed strong success rates and further supports
the idea that practitioners and patients no longer view monovision as the
standard for managing presbyopic patients. To help practitioners narrow the
field of which multifocal lens to reach for first, Foresight Regulatory, with
the help of four leading optometrists (Lee E. Rigel, OD, FAAO; Rob Davis, OD,
FAAO; John Schachet OD, FAAO; and Paul Klein OD, FAAO) recently conducted a
multi-site comparative evaluation of the Frequency 55 Multifocal (CooperVision)
and the SofLens Multifocal (Bausch & Lomb).
The randomized, open-label, two-week dispensing
crossover study compared distance and near visual acuity, ocular physiology,
fitting ease, subjective comfort when worn for daily wear and overall success.
None of the evaluators knew of the sponsor (CooperVision) and the patients had
no previous experience with either contact lens brand.
Investigators completed study evaluations for each
subject at the initial/dispensing visit, one-week and two-week visits and at 48-
to 72-hour post-dispensing fitting evaluations for each of the two lens brands.
If the subject couldn't achieve a good fit with the first pair of lenses, then
an investigator trial fit and dispensed a second pair. If the subject couldn't
be fit with either the first or the second brand of lenses, then he was
discontinued from the study.
This study evaluated the
qualitative and quantitative aspects of the two multifocal lens brands mentioned
above. Four investigators from geographically diverse sites recruited 60
presbyopic subjects who had normal eyes and were generally successful soft
contact lens wearers for the study. In all, 51 subjects completed the study,
three exited during enrollment and six discontinued during the evaluation.
Of the 60 subjects recruited for the evaluation, 11
were male and 49 were female, all ranging in age from from 43 to 71, with an
average age of 52.2 years. Overall, these were experienced contact lens wearers,
with an average of 17.7 years of contact lens wearing experience (Figure 1). An
average pupil size of 4.17mm was reported with a range of 2mm to 6mm.
Investigators randomly trial fit each subject with
one of the multifocal lens brands. They dispensed the lenses to subjects at the
initial/dispensing visit and evaluated them again after 48 to 72 hours to assess
lens fit, vision and comfort. The investigators scheduled follow-up visits six
to nine days after the initial fitting and evaluation and collected quantitative
data to measure visual acuity and ocular physiology. Additionally, subjects
answered a series of qualitative questions about the lenses. Subjects went
through the same process for the second (randomly chosen) brand of lenses.
Figure 1. Length of time the
60 subjects had worn lenses.
Results and Discussion
While both lenses performed well in this study,
clinical investigators identified many characteristics of Balanced Progressive
Technology (Frequency 55 Multifocal) that provide an advantage in managing
presbyopia, particularly in regard to the range of add powers available and the
flexibility of the lens design while fine-tuning the fit. Dr. Rigel said, "The
fitting system of the Frequency 55 Multifocal is simple and straightforward.
Perhaps the best feature of this lens is that the practitioner can make small
incremental changes in vision." He continued, "We tend to like this because this
option provides control of the direction of the fit and with minor tweaks,
adjustments and modifications, we can enhance and improve our patients' fits."
The simplicity of the Frequency 55 Multifocal
fitting system mainly results in the large number of lens parameters available
(+4.00D to �6.00D spheres in 0.25D steps, with each sphere power available in
four add powers and either a "distance" or "near" design). Therefore, for each
sphere power, the Frequency 55 Multifocal effectively has four times as many
power designs compared to the SofLens Multifocal. For example, for a �3.00D
sphere power, the Frequency 55 Multifocal has +1.00D, +1.50D, +2.00D and +2.50D
adds with each available in a "D" or "N" add. By way of comparison, the SofLens
Multifocal has only a "low" and a "high" add in the �3.00D sphere power.
Snellen distance acuity was similar between the two
lens brands. However, when compared by eye and binocularly, Jaeger near visual
acuity was better with the Frequency 55 Multifocal lens. A by-eye comparison
revealed that 60.2 percent obtained J2 or better with the Frequency 55
Multifocal, vs. 48 percent with the SofLens Multifocal. Binocular near visual
acuity with the Frequency 55 Multifocal lenses was J2 or better in 79.6 percent
of the subjects as compared to 74 percent of the SofLens wearers.
Patient questionnaires further demonstrated a
preference for the Frequency 55 Multifocal when attempting close-up tasks such
as makeup application and reading a watch (Figure 2). "We shouldn't overlook the
slightly better performance of the Frequency 55 Multifocal lens in near visual
acuity," stated Dr. Rigel. "After all, most emerging presbyopes come into our
practices complaining of difficulty with near vision. Our challenge is to always
improve near vision without degrading the excellent distance vision to which our
emerging presbyopic patients are accustomed."
The stereopsis with the Frequency 55 Multifocal's
Balanced Progressive Technology is better (lower value) at both baseline and at
follow up (61.3 and 54, respectively) compared to the baseline and follow-up
values of the SofLens (67.2 and 83, respectively). With a measurement of 54
seconds of arc, the Frequency 55 Multifocal is much closer to the ideal
stereopsis measurement of 40 seconds of arc, as compared to the SofLens
measurement of 88 seconds of arc.
Frequency 55 Multifocal lens provides advantages in stereopsis and contrast
sensitivity," reported Dr. Rigel. "This lens is also excellent for monovision
wearers who are reaching a point where too much disparity exists between near
and distance vision. The full range of vision from the Frequency 55 Multifocal
lens makes this lens an excellent solution to a common problem."
Subjects successfully fit quickly adapted to the
test lenses and as many as 86.2 percent of subjects wore their contact lenses
seven days each week, many for as long as 19 hours each day. Comfort is critical
to successfully supporting these wearing schedules. The aggregate questionnaire
responses related to "overall comfort" demonstrated a preference for the
CooperVision Frequency 55 Multifocal lens by a small margin.
2. Patient evaluation of near vision in a variety of
A Clear Preference
Practitioners and patients welcome a multifocal lens
that can provide ease of fit, comfort and a range of crisp visual acuities. The
clinical evaluation previously summarized reveals that while the visual
performance between the two lenses was comparable in terms of distance vision,
the Frequency 55 Multifocal provided better near vision when compared to the
SofLens Multifocal as demonstrated by the Jaeger visual acuity measurements and
supported by the questionnaire responses.
Further, the Frequency 55 Multifocal provided superior stereopsis as compared to
the SofLens Multifocal. Also, a key advantage reported was the availability of
the Frequency 55 Multifocal in a wider range of add powers and the flexibility
of its design and fitting system as far as fine tuning the final fit.
In the course of this evaluation, certain advantages
came to light with regard to the Balanced Progressive Technology in the
Frequency 55 Multifocal lens. "Of all the lenses on the market, the Frequency 55
Multifocal is my initial lens of choice," said Dr. Davis. "I have opportunities
with this lens to fit patients I couldn't help with other designs. The wide
range of add powers, combined with a fitting system that allows me to address
each eye independently, gives me the flexibility to meet my patients' needs that
I just can't find anywhere else."
"Academically speaking, the core advantage of the Frequency 55 Multifocal is the
flexible design with a distance-sighted lens and a near-sighted lens," said Dr.
Davis. "Initially, I fit a D lens on the dominant eye and the N center lens for
the nondominant eye. But if I wish to further refine acuity in a small
percentage of my patients, I do have the option to mix two D or two N lenses,
which is something unique to the Frequency 55 Multifocal lens. I have the
flexibility to tailor the design to the individual needs of my patients."
This multi-center clinical evaluation revealed that
the Frequency 55 Multifocal's extensive range of add powers is attractive to
practitioners and is therefore an advantage over the SofLens Multifocal system,
which offers only a "low add" and a "high add" profile. Said Dr. Schachet,
"There's an advantage with the Balance Progressive Technology. Multiple add
powers and different N and D lenses allow me to tailor near and distance vision
while keeping the core prescription the same. A nice advantage over the SofLens
Multifocal is its superior performance for patients who have higher add powers,"
he continued. "Now we don't have a concern when the patient comes in two years
later needing additional correction. We can keep him in the same lens and just
change the add power. This design keeps me from wasting my valuable chair time,
and I don't have to start over every time a patient comes in."
Excellent Design, Enhanced Material
Recent enhancements to the lens material have
integrated the lens dryness and discomfort combative material of CooperVision's
Proclear line of contact lenses (omafilcon A, 62 percent water content). Given
the tendency of the presbyopic patient demographic to experience dry eye
symptoms, practitioners are eager to finally have the technology of the Proclear
material together with the Balanced Progressive Technology design of the
Frequency 55 Multifocal. "My nonpresbyopic Proclear wearing patients love this
material," said Dr. Schachet. "I'm excited to be able to offer the Balanced
Progressive Technology design in the Proclear material. Now I'm confident that
patients who were already successful in the Frequency 55 Multifocal design will
become even more successful with the comfort enhancements of the Proclear
Embrace the Best Presbyopic
Multifocal lenses are swiftly
emerging as a lens of choice for managing presbyopia. Results from this
evaluation, together with anecdotal experience from our respective practices,
point to new support for the Balanced Progressive Technology available in both
the Frequency 55 Multifocal and the Proclear Multifocal as the multifocal lens
of choice for all presbyopic patients from emerging to advanced.
One thing is certainly clear: New materials and
wider options are paving the way for happy patients with longer lens-wearing
cycles. The time has come to raise the bar, abandon monovision and provide our
patients with the binocular and full range of vision that they deserve.
Dr. Rigel is a fellow of the American Academy of
Optometry and is a diplomate of the Academy's Cornea and Contact Lens Section.
He's also presently chairman of the Foresight Optometric Meeting and the
American Society of Corneal Refractive Technologies.
Dr. Davis has worked extensively in the management
of eye care for more than 20 years. He has developed many contact lens designs
and is a Fellow and Diplomate in the American Academy of Optometry.
Dr. Schachet has a large, private contact lens
practice in Englewood, CO, where he specializes in dry eye, allergy and CRT.
Dr. Klein is in private group practice
specializing in contact lens care, therapeutic optometry and laser vision
correction in Fort Lauderdale, FL. He's also an adjunct professor of optometry
at the Pennsylvania College of Optometry and has published and lectured
Contact Lens Spectrum, Issue: February 2005