What is monovision cataract surgery?
Monovision cataract surgery San Diego
A cataract is a clouding of the natural lens of the eye. This is a clear structure located just behind the pupil, and it acts to focus light onto the retina (the light-sensing tissue at the back of the eye). With age, the proteins in the lens break down, which causes it to become cloudy.
Cataracts are a very common cause of vision loss worldwide. Fortunately, they’re also highly treatable. During cataract surgery, the damaged natural lens is removed from the eye. It’s then replaced by an artificial lens, which is known as an intraocular lens, or IOL. The procedure takes just a few minutes, and the effects are permanent, since new cataracts can’t form in the artificial lens.
After traditional cataract surgery, distance vision is clear, but people generally depend on glasses for things like reading. However, there are a few different options that can reduce or even eliminate the need for glasses after cataract surgery. One of these options is monovision.
What is monovision, and how does it affect vision after cataract surgery?
What is vision like after traditional cataract surgery?
A traditional intraocular lens (IOL) is monofocal, meaning that it has just a single focal distance. Generally, this is adjusted for clear distance vision. If you wore glasses or contacts for distance vision before your procedure, then the monofocal IOL can be adjusted accordingly, so you likely won’t need correction for distance vision after cataract surgery.
Your eye’s natural lens changes its focal distance by changing shape. That’s how you’re able to seamlessly shift between distance and close vision in your daily life. However, a monofocal IOL isn’t able to change shape, so it can’t change focal distance. That’s why, after traditional cataract surgery, people have clear distance vision, but they need glasses for things like reading or looking at a computer screen.
How does monovision work?
With traditional cataract surgery, the same monofocal IOL is used in each eye. If the eyes have two slightly different prescriptions (which is very common), then the two IOLs will be slightly different from each other, but they’ll both be adjusted for clear vision at the same distance.
The difference with monovision is that the focal distance is set differently in each eye. For one eye, the IOL provides clear distance vision. For the other eye, the IOL is set for clear near vision, allowing for activities like reading.
The downside of monovision is that there’s an adjustment period required. The brain can take a few weeks to adjust to the different inputs coming from each eye. This can be disorienting and uncomfortable during the early period. However, for most people, the brain is able to adjust.
In many ways, after the adjustment period is complete, monovision is somewhat similar to wearing bifocals. You have two different distances where your vision is clear. Once the brain learns to transition seamlessly between them, you’ll be able to shift easily between distance and near vision, instead of needing to put on reading glasses to see close up.
Although most people are able to adjust to monovision, this doesn’t always occur. Some people find that monovision continues to be uncomfortable and disorienting, and the brain never really adapts to having different inputs from each eye. Different studies find different rates, but it’s generally believed to occur in about 10 to 20% of people. If possible, it can be helpful to do a trial of monovision using contact lenses. After wearing these lenses for a few weeks, you can determine whether you find monovision to be comfortable and convenient, or whether you’d prefer a different option.
Monovision cataract surgery San Diego
Monovision isn’t the only option for cataract surgery. Premium IOLs, such as multifocal or accommodating IOLs, can also help to reduce or eliminate the need for reading glasses after cataract surgery.
If you or a loved one is experiencing cataracts, we invite you to make an appointment with one of our expert eye surgeons. They’ll explain all of your options, and will help you to make a choice that works with your lifestyle and preferences. Simply contact our front desk to schedule your appointment.
