Article Date: 2/1/2008

Focusing on an Underserved Population

Focusing on an Underserved Population

Learn how the astigmatic presbyope can help grow your contact lens practice.

BY JASON MILLER, O.D., M.B.A.

As Dr. Winnick noted in the previous article, the maturing baby boom population creates a unique opportunity for contact lens practitioners, who now have new products, materials and fitting modalities to help satisfy these patients.

A survey by the Contact Lens Council1 reported that more than 40% of consumers are not aware that multifocal contact lenses are available, and 83% of those surveyed would be interested in trying them if the contact lenses would satisfy their visual requirements. The fact that there are an estimated 45 million Americans, or 1 in 6 people, with significant astigmatism2, as well as the large number of emerging presbyopes, many of whom are long-time toric lens wearers, gives us a huge opportunity to fit this growing segment in multifocal toric lenses.

One of the newest advances in the contact lens market is the Proclear Multifocal Toric from CooperVision. This lens combines the toric technology used to correct astigmatism with the most advanced multifocal technology used to correct presbyopia, answering a long-standing need among astigmatic patients. In this article, I'll describe my experience prescribing this lens for a typical patient.

Diagnostic Data

Mark, 48, presented with a history of soft, spherical multifocal contact lens wear and was complaining of blurred distance and near vision with his current lenses. He was considering stopping contact lens wear due to the loss of clear, crisp vision.

Mark is an engineering manager and works at a computer half of the day. He had no complaints of dry eyes or discomfort with his current contact lenses.

As we know, patient selection is a key to success with multifocal contact lenses (Tip: Avoid using the word "bifocal."). Is the patient motivated? How are the patient's eyes used throughout the day?

Mark had been wearing his current contact lenses for 2 years, and he enjoys the freedom contact lenses provide over spectacles. His manifest refraction was:
OD: –0.50 –1.00 × 174 20/20
OS: –0.75 –1.00 × 018 20/20
Add +1.75

External and internal ocular examinations revealed both eyes were clear and quiet.

Doctor-Patient Decision

After reviewing his various contact lens options, Mark and I concluded the Proclear Multifocal Toric was the best choice for him. I discussed appropriate visual expectations (that these lenses would allow him to have clear distance, intermediate and near vision for most visual tasks), the fees involved and the importance of follow-up care. I described the basics of the lens design and, as this is a custom-made lens, the expected time it would take for the fitting, fabrication, shipping and subsequent progress visits.

This pre-fitting discussion is a very important component of managing a patient's contact lens care. In this case, Mark wanted improved vision at distance and near if he was going to continue wearing contact lenses. The Proclear Multifocal Toric provides a high amount of flexibility toward achieving that goal. I further explained how I'd modify (Tip: use the word "modify" or "customize" instead of "tweak.") the lenses to meet his specific visual needs.

Starting Point

The Proclear Multifocal Toric is available in base curves of 8.4 and 8.8, powers from +20D to –20D sphere, cylinder from 0.75 to 5.75, axes 5° around the clock, +1.00D to +4.00D adds and in both a D and an N lens design, which enables a balanced visual experience at all ranges.

After determining Mark's right eye is his dominant eye (using a +2.00D flipper in the phoropter), I ordered the initial diagnostic lenses (Tip: Avoid using the word "trials.") as follows:
OD: –0.50 –0.75 × 175 / +1.50 Add / D lens
OS: –0.75 –0.75 × 020 / +1.50 Add / N lens

I try not to vary my starting point too much, unless the patient stresses that distance or near vision is more important. In that case, I will push the prescription in that direction. I allow the lenses to settle for about 15 minutes. Patients really don't want to sit in the office for 30 minutes just to give their contact lenses time to settle.

The real work comes during the progress visits. I encourage patients to wear the lenses as much as possible to help their eyes adapt, then schedule a follow-up visit after 1 week. Waiting any longer may risk the chance that a patient will give up on the lenses if additional modifications are necessary.

Dispensing and Progress Checks

At the dispensing visit, Mark was seeing 20/20 OU at distance and 20/30– OU at near. The lenses were perfectly centered, which is another key to success with these lenses.

I have found that comfort problems are rarely an issue with Proclear Multifocal Toric lenses, which are made with PC Hydrogel material that has been proven to produce a high level of wearing comfort as the material is highly resistant to dehydration and protein deposits. Mark was no exception. He reported the lenses felt comfortable. I assured him this was a great start and scheduled the 1-week progess visit.

During the 1-week progress visit, I realized Mark's right eye would accept more plus, which is a great scenario. This change improved both his distance and near vision. I also needed to make a minor axis adjustment OS (the lens rotated 5° temporally, therefore I adjusted it to axis 015) using the LARS (left add, right subtract) technique. (Tip: I use ToriTrack if the lens rotates off more than 10°; otherwise, I start with the LARS technique for troubleshooting the axis.)

I ordered a new pair of diagnostic lenses. Mark picked them up and scheduled his next progress visit 1 week later. He returned ecstatic with his new vision. His final Rx was:

Proclear Multifocal Toric
OD: –0.25 –0.75 × 175 / +1.50 Add / D lens
OS: –0.50 –0.75 × 015 / +1.50 Add / N lens

Distance visual acuity was 20/20- OD and 20/30- OS. Near visual acuity was 20/50+ OD and 20/25- OS. Binocularly, Mark was 20/20 at distance and 20/25– at near. He said he was excited to tell his coworkers about his experience at our office. His visual needs were exceeded.

Why Correct the Low Astigmat?

We know that uncorrected astigmatism results in distorted or blurred vision and a loss in "crispness" of visual acuity. It can cause headaches and eye fatigue. We also know some "crispness" of vision is lost with soft multifocal contact lenses. If we try to mask cylinder when prescribing a soft multifocal, the overall loss adds up, and the success rates decrease.
We can help eliminate some of that loss by correcting even low amounts of astigmatism. If you have any doubts, just hold a diagnostic lens cylinder in front of a patient's spherical-only correction and ask which way is preferred.

Get a Competitive Edge

You have many competitors in the contact lens industry. Being comfortable and proficient in satisfying the needs of astigmatic presbyopes is critical to the success of your contact lens practice. The newer multifocal designs provide good optics and comfort, allowing you to take advantage of this demographic opportunity. Not only will you increase profitability by offering this specialized contact lens service, but you will increase referrals as well.


Dr. Miller is in a partnership private practice in Powell, Ohio. He is an extern preceptor for fourth year students at The Ohio State University College of Optometry, and he is the Central Ohio InfantSEE Coordinator. You can contact Dr. Miller at (614) 296-1175 or jasonrmiller@columbus.rr.com.

References
  1. Contact Lens Council. New Survey Finds More Education on Contact Lenses and Lens Care Will Help Consumers See 20/20. PR Newswire. Aug. 15, 2007.
  2. Prevalence and Incidence of Astigmatism. wrongdiagnosis.com.


Optometric Management, Issue: February 2008