It’s a battle that’s been “raging” since the mid-1980s when soft bifocal contact lenses were first introduced. Vistakon got in to the game early with the Acuvue Bifocal and CibaVision followed shortly thereafter with their Focus Progressives. Both were better than nothing, but I was never really impressed with either, and monovision often won out.
If you’re not familiar with monovision, it’s a contact lens option that lets one eye have a prescription for seeing far away and the other is prescribed a lens to see near. As I tell my patients, it’s a “prescribed compromise” to reduce your dependency on reading glasses. Because of the slight visual imbalance it creates, this tends to work best for those people who do a little bit of everything during their day. But it doesn’t tend to work as well for those who may be in front of the computer constantly, drive a lot, or who spend a lot of time in dim lighting.
Historically, I’ve probably fit close to 75% of my patients in monovision (vs. bifocals) over the years since I started practicing 12 years ago, because it just seemed to give patients better vision than the multifocal contacts that I had available.
But the tide has turned with the introduction of Coopervision‘s Biofinity Multifocal and CibaVision’s Air Optix Multifocal. These designs have actually made it easier to deliver clearer, more functional vision to each patient. They work on a design principle known as “simultaneous vision”. Since you can’t look through the top or bottom half of a contact lens, the reading power is normally placed in the middle of the contact lens like a bullseye. You are therefore required to look through both powers at the same time. It’s kind of like looking through the screen on a window. You can look at the screen or ignore it and focus through to a farther distance. See below for the design idea and click the pictures to make them larger.
Neither design is perfect. And a good pair of progressive lenses should give you superior vision. But it’s as good as we’ve ever had it in soft contact lenses. I now recommend multifocal contact lenses before monovision, probably almost 70% in favor of multifocals.
Expectations are a key to success. I make sure to go over the basic design of the lenses. And I always mention that you should get better vision in good lighting and poorer vision in dim lighting. If you have astigmatism, it will limit our overall success with these designs. But Coopervision has a Proclear Multifocal Toric that does a decent job.
So this may not answer all your questions about multifocal contact lenses, but this post addresses most of the things that I talk about with my patients. If you’ve been curious about them, feel free to schedule an appointment. I see patients at the Alamo Heights Vision Source on Mondays and Thursdays. And I am at the Los Patios Vision Source on Wednesdays, Fridays and Saturdays.
Click this link: http://www.allaboutvision.com/contacts/bifocals.htm to find out more information about bifocal contact lenses.
Thanks for reading and feel free to send me questions!
- The contact lenses that could be the future of augmented reality (business.financialpost.com)
- Multifocals May Not Be The Answer To Driving In The Dark (prweb.com)