During cataract surgery the natural lens is removed and an artificial lens is placed into the capsule of your natural lens, colloquially known as “the bag”. Many people want to know what type of lens should be implanted, and this article will help you to better understand the decision-making process.
Understanding Your IOL Decision
Many people who are candidates for cataract surgery also have presbyopia, the natural age-related loss of close-up focusing ability, as well as astigmatism, an abnormal curvature of the eye causing blurry vision. Recent developments in artificial lenses (IOLs) mean that it is possible to address all of these problems with modern-day cataract surgery
Questions Worth Thinking About Beforehand
There is no right or wrong decision when choosing which IOL is right for you. Consider the following questions to help you and your doctor make an educated decision about your IOLs.
- What activities will you participate in after surgery?
- Will you drive at night? How often? Is it necessary for your job?
- Are you okay with paying an additional cost? How much?
- Are you ok with halos and/or other visual anomalies?
Monofocal IOLs Are The Standard Option
A monofocal lens focuses on a single distance. These are the traditional IOLs that are universally paid for by Medicare/Insurance. They offer the sharpest night-time vision, best contrast sensitivity, and do not require adaptation. Most people who receive monofocal IOLs are focused for distance and require a pair of reading glasses after surgery.
Monovision Strategy
A strategy that can be employed with monofocal IOLs is monovision. In this scenario one eye is set up for distance, and the other for close-up. Over time, your brain learns to combine images to see well at multiple distances. Monovision with monofocal IOLs is covered by Medicare/Insurance, but will require adaptation and have somewhat diminished depth perception
Toric IOLs: Correcting Astigmatism
Many people who are candidates for cataract surgery also have astigmatism, an abnormal curvature of the eye that causes blurry vision. Toric lenses were developed to help with astigmatism and contain different strengths in different directions to compensate for your astigmatism, helping you see well in the distance without glasses. During surgery, the doctor has to make sure that the lens is implanted in the right direction to get the best possible correction. These lenses also require reading glasses, and generally cost about $1,000 to $1,500/eye.
Multifocal IOLs Offer Multiple Focal Points
These lenses break up light in order to provide good vision at several different distances. Multifocal lenses generally take some amount of adaptation, typically two to three months, although it can take as long as one year for full adaptation. Multifocal lenses cost about $2,500 to $4,000 or more/eye.
Most people who get multifocal IOLs (~80%) are happy with the results and don’t require glasses for near or far. Satisfaction with multifocal IOLs varies from 60 to 100% based upon patient selection and expectations.
Multifocal IOLs should be avoided in people who drive professionally at night, people with other significant retinal conditions, people that do not do well with visual anomalies, and in people with unrealistic expectations. Some people will notice halos at night with multifocal IOLs, and contrast sensitivity is not as good as monofocal IOLs. Most people adapt to these problems, but they should be taken into consideration.
Overall, about 10.8% of multifocal patients may be retreated, usually because of residual refractive error. Less than 1% will be retreated by exchanging the multifocal IOL for difficulty with adaptation.
What Adaptation Looks Like
In order to understand the process of choosing an IOL it helps to understand what adaptation is all about. When you have multifocal IOLs placed in your eye, the way the light enters the eye is significantly different than it was when you had your natural lens. Your brain has to adapt to the way the images are coming through the multifocal IOLs and learn new tricks to help you see well with them.
This process of adaptation takes some amount of time. Most patients with multifocal IOLs take about two to three months to get used to their new lenses. Some people will continue to adapt to their lenses for one year.
It is helpful to remember that adaptation is a skill, and the brain has to learn a whole new process for interpreting images. Just like learning to play a musical instrument, adaptation takes time and dedication.
Extended Depth of Focus (EDOF) Lenses
The most recently introduced lenses are extended depth of focus lenses. These lenses fall somewhere in between monofocal and multifocal lenses. Instead of two or three distinct focal points, EDOF lenses offer an elongated area of focus. These lenses have been reported to offer excellent distance vision, very good intermediate vision, and serviceable near vision, though many will still need glasses for smaller print. These lenses have fewer halos than traditional multifocal lenses, better contrast sensitivity, and are reported to be easier to adapt to.
IOL Types Comparison
| Lens Type | Distance | Intermediate | Near | Glasses Needed | Night Vision | Insurance Coverage |
|---|---|---|---|---|---|---|
| Monofocal | Excellent | Poor | Poor | Yes (reading) | Excellent | Covered |
| Monofocal (Monovision) | Very Good | Good | Good | Minimal | Good | Covered |
| Toric | Excellent* | Poor | Poor | Yes (reading) | Excellent | Partial |
| Multifocal | Good | Good | Good | Minimal | Fair | Premium only |
| EDOF | Excellent | Excellent | Fair-Good | Maybe | Good | Premium only |
*With astigmatism correction
Making Your Decision
Now that we’ve gone through some of the available options, what’s the best lens for you? This is a decision that can only be made between you and your ophthalmologist after detailed measurements and discussions about the trade-offs with each type of lens. If you’re interested in premium IOLs, it’s important to have these discussions well before surgery so that you can be sure you’re making the best decision for your eyes.
Eye Health
Certain conditions may limit the benefit you receive from premium lenses. Severe dry eye worsens vision with multifocal IOLs. Advanced macular degeneration will limit the potential benefit of premium lenses. Glaucoma with visual field loss can make adapting to the new lens more difficult. A history of refractive surgery, like LASIK, does not rule you out for premium lenses, but may require more tests before surgery. It’s important to discuss any history or current symptoms with your ophthalmologist to determine the best options for your eyes.
How You Handle Imperfection
There are pros and cons to every type of IOL, but it’s not always easy to put a dollar amount on the cons of a certain type of lens. Here’s where you have to be honest with yourself about your ability to tolerate the trade-offs with premium IOLs. Some people do extremely well with halos and others cannot stand them. Some people hate losing a bit of contrast and others barely notice it. This is why it’s critical to have a thorough discussion with your doctor before surgery.
A Few Things Patients Ask Later
When is the second eye operated on?
Cataract surgery is almost always performed one eye at a time, and patients wait one to two weeks to have the other eye operated on.
How long will my new lens last?
Your new lens will never need to be changed again, they do not wear out, but some patients develop posterior capsule opacification, also called a “secondary cataract,” which can be treated with a quick laser procedure in the office. Natural cataracts can’t come back.
Can they change my lens in the future if new technology becomes available?
Technically, new IOLs can be implanted, but this is a bigger operation that is rarely necessary. About 0.2-0.3% of the time, a lens exchange operation may become necessary.
IOL Lens Frequently Asked Questions
Should I pay for premium IOLs?
Medicare and commercial insurance pays for monofocal lenses. Other types of IOLs are additional expenses to patients ranging from $1,000-$1,500/eye for toric, $1,500-$2,500/eye for EDOF lenses, and $2,500-$4,000/eye or more for multifocal lenses. When deciding if it makes sense to invest in a premium IOL, patients can think about the cost of prescription eyeglasses. Good quality regular glasses can be $300-$800 and progressives can be $400-$1,000 or more. These need to be replaced every couple of years. Over the next twenty years, glasses can cost thousands of dollars ($6,000-$16,000+).
What are the chances I’ll be satisfied with a lens that corrects presbyopia?
Studies show an overall dissatisfaction rate of ~18.5% with IOLs that correct presbyopia, but this varies widely from study to study and depends on the type of lens. Most of the time, patients are unhappy due to needing glasses after surgery for distance, near, or intermediate vision or because of halos/glare, but these symptoms improve over time as the brain learns how to process information from the new lens. Rarely are patients unhappy with the actual type of lens implanted in their eyes. Studies show patients that adapt well to multifocal IOLs tend to have done well with progressive lenses, value independence from glasses, have healthy eyes, accept there are tradeoffs with multifocal IOLs, are patient while their brain is learning how to see with their new lenses, and have reasonable expectations.
Talk It Through
Horizon Eye Care fellowship-trained cataract surgeons will answer any questions you have about premium lenses, discuss your visual goals for distance, intermediate, and near, and perform additional tests to determine if you’re a good candidate for toric or other premium lenses. To schedule a cataract consult with our eye surgeons in Charlotte, sign up online or call us at (704) 365-0555.
