prescribing for presbyopia
The Emmetropic
Presbyope
BY THOMAS G. QUINN, OD, MS, FAAO
It was the best of times. It was the worst of times. The patient in your chair is wildly enthusiastic about pursuing soft bifocal contact lens correction. The problem? He has been emmetropic for the past 40 years. Oh, no! Alas, there is hope. Before throwing in the towel, try this approach. It's not perfect, but I guarantee that your success rate with this challenging population will grow.
Understanding the Task
Never will you meet more motivated patients. They've existed all their lives without the need for spectacle correction....and they don't want to give up this great freedom just because their focusing ability is failing.
This blessing of perfect distance vision can become the contact lens professional's curse. These patients don't want you doing anything to disturb this perfect world! The key to success is lowering expectations.
I know some of you are saying, "I've already tried that." Well, there's an added twist.
Old Reliable with a Twist
Begin as you always do with all of your bifocal contact lens candidates, by explaining that simultaneous vision lenses allow both distance and near light to enter the pupil at the same time. Emphasize how this allows them to see far and near in any direction of gaze. Explain that they may need to give up a little in the distance in order to see at near.
Of course, they'll all nod their heads and say, "No problem. Just don't give me bifocal glasses, Doc." Well, you know what happens next. You apply a pair of lenses, have the patients explore their visual world out in the reception area for 15 to 20 minutes, invite them back to the examining room and inquire, "How are you seeing?" Their response (say it with me, people), "It's terrible!" To add fuel to the fire, they subsequently will zip off the 20/20 line on the distance acuity chart.
Wait! Don't throw your flipper lenses at them yet. You expected this response, and you are ready for it. Now, it's time for Super Doc to come to the rescue!
|
Keys To Success: |
|
|
Ask the patients to view the distance acuity chart. Then, with your clean hands, reach up and remove the bifocal lens from the dominant eye. Ask the patient, "How's your vision now?" The vast majority of the time they'll respond, "That's a lot better!" (or something along those lines).
Now you hand them a nearpoint chart with text and ask them, "How is your near vision?" Most will find it very acceptable. Now we're getting somewhere! What happened here?
Lowering the Bar
What we've done is reset the bar. Emmetropic patients begin the fitting process with the bar set way too high. By applying a bifocal lens to each eye and allowing the patient to experience the vision under these conditions, we've lowered the bar to an achievable level.
Don't try to simplify this process by initially applying a bifocal lens on the non-dominant eye only. Emmetropic presbyopes won't be happy with their distance vision because their bar has not yet been reset.
Reset the bar and reap the rewards.
Dr. Quinn is in group practice in Athens, Ohio, and has served as a faculty member at The Ohio State University College of Optometry.