MONOVISION
The obvious translation is "seeing with one eye". Well, that's partly true but it's not as bad as it sounds. Monovision is a term we use in the eyecare profession that relates to the fitting of contact lenses for people who need bifocals, or at least those people that require a unique prescription for distance and one of a different strength for reading. There have been numerous attempts to develop a good bifocal contact lens but the efforts to date have fallen way short. The advantage of a well designed bifocal contact lens would be the resultant "balanced" vision between the two eyes. With the monovision system, we intentionally create an imbalance.
Rather than dwelling on the pros and cons of bifocal contact lenses, suffice it to know that monovision wearers outnumber bifocal wearers, 4 to 1, so this article will concentrate on the monovision system. If you have been a happy contact lens wearer for years and suddenly notice that "your arms are getting shorter", you may simply opt for a pair of reading glasses to be fit "over" your contacts. This will work quite well and offer very good vision for those who don't mind an occasional use of glasses. However, if you find the idea of wearing glasses along with your contacts a bit redundant or just a hassle, then consider yourself a potential candidate for monovision.
A lens with your determined reading prescription will be placed on your non-dominant eye and your dominant eye will hold the lens for distance. At least, this is the way I usually begin, but a switch is not uncommon. Most people will read 20/20 at distance and 20/20 at near with both eyes open. Obviously if you cover your "distance eye" and try to read a street sign with your "reading eye", you will be greatly disappointed. And vice-versa, trying to read the newspaper with just your distance eye will not be possible. This is NOT a perfect solution but it works; and it works better than it sounds.
Monovision is an ADAPTIVE procedure. You will not become totally comfortable with it in five minutes. It may take from 3 days to 3 months to adjust, although most patients who are highly motivated will adapt in a week or two. Most of your daily tasks will be well handled with monovision, but there are a few situations that probably never "come around". The first one is driving at night. Oncoming headlights and street lights may cause an undesirable glare through the reading eye. Daytime driving does not appear to be a problem. The second most common complaint I will hear is fatigue with extended reading periods. The shorter (30-60 minutes) reading periods can be accomplished quite well.
The praises for the monovision system are quite numerous: "It's so nice not to have to find my glasses to simply write a check or to see a price tag"....."I'm now the only one at the table that can see the menu without glasses"....."Now I don't need my glasses to see what I'm eating"....."I can actually read and watch TV at the same time"....."I am able to focus on the computer screen without tilting my head back to look through my bifocals".
And the complaints: "Night driving is quite a challenge"....."I get fatigued quicker with a lot of reading"....."I wish my vision was a little clearer"....."I see better when I close one eye"....."There is a slight haze to my vision".
There is another group of candidates that I haven't yet mentioned. Those people who have never worn glasses or contacts and turn that corner at 42. Now you need a little help with your reading, and wearing one contact lens may just do the trick. It's also a little easier handling and caring for just one lens and the cost is somewhat less.
If the monovision concept sounds intriguing to you and you would like to investigate alternatives to those bifocal glasses, consult your eye doctor for a monovision workup. In many cases a disposable lens can be used and you can test the concept "in your world" before you commit.