prescribing for presbyopia
Switch Your Presbyopic Strategy
BY N. REX GHORMLEY, OD, FAAO
The presbyopic population holds unlimited potential for you to grow your contact lens practice. In the future the United States will consist of more than 100 million
presbyopes, and experts add four million are added to that
four million to that total for every year that follows.
If you want your practice to take full advantage of this opportunity, then be creative and use all of the presbyopic contact lenses that are currently available. You have six options to offer each presbyopic contact lens patient you care for:
1. Distance contact lenses and reading glasses
3. Modified monovision
4. Bifocal contact lenses
5. Modified bifocal contact lenses
6. A spherical lens and a bifocal lens
Evaluating the Patient
A few months ago, JB, a 45-year-old female, came to my office for a contact lens evaluation. She wears eyeglasses for all nearpoint tasks but wanted to see if she could wear contact lenses. Her spectacle prescription was +0.75D sphere OD, +1.00D sphere OS with an add power of +1.25D OU. Biomicroscopy was normal and her left eye was dominant.
I fit JB with CooperVision's Frequency 55 Multifocal diagnostic soft lenses: +0.75D center-near N lens with +1.50D add OD and +1.00D center-distance D lens with +1.50D add OS (both with an 8.7mm base curve). After a 10-minute stabilization period her visual acuity was OD 20/20 near, 20/30 distance and OS 20/30 near, 20/20 distance. Under binocular conditions she reported "very good vision" at distance and near.
Deciding What to Fit
Using the monovision technique, we placed a Frequency 55 +2.25D lens on JB's non-dominant eye (OD) for near and a Frequency 55 +1.00D on the dominant eye (OS) for distance (both with an 8.7mm base curve). JB achieved 20/20 visual acuity at distance and 20/20 at near, but reported that her "vision didn't really look normal."
Interestingly, this patient obtained 20/30 distance acuity in her right eye (near lens) with the multifocal system and only 20/80 distance acuity (near lens) with the monovision system. We fit her in multifocal soft contact lenses. She now wears them full time and is a happy, successful patient. She's even referred several of her friends to our office for bifocal contact lens fitting.
I used to start the majority of my presbyopic contact lens patients with monovision. It was simple, took little of my time and my "success" was fairly high. Back then I used bifocal contact lenses only for patients who were unhappy or who failed.
The point of JB's story is that today my clinical plan for the presbyopic patient is different than it was in the past. I now consider a bifocal lens system first and use monovision if I can't achieve success with bifocal contact lenses. Why did I change?
- I began to listen to my monovision patients. They like their lenses, but they want a better option. They also don't like their monovision while driving at night.
- We now have many new soft and gas permeable bifocal lens designs that provide good distance and near vision.
- I work hard to achieve excellent binocular vision with my spectacle lens patients -- why shouldn't I use the same criteria for my contact lens patients?
Re-evaluate Your Protocol
As Spencer Johnson, MD, said in his now famous book Who Moved My Cheese, "If you do not change -- you can become extinct." We all need to change, and I suggest that you look at your current clinical approach to fitting presbyopic patients and evaluate if it will move you successfully into this millennium.
Dr. Ghormley is a diplomate of the American Academy of Optometry's Cornea and Contact Lens Section and is the team optometrist for the St. Louis Rams (NFL) and the St. Louis Blues (NHL).