Tips to choose the best lens for cataract surgery

Every year, millions of people have routine surgery to replace a cataract — that is, a lens in the eye that has become clouded. Cataracts cause foggy or blurred vision that makes it hard to do everything from reading to driving. Replacing the lens restores clear vision. It can also correct other vision problems and reduce your dependence on glasses. "Think of it as customizing the lens to the focusing powers that will suit you best," says Dr. Nandini Venkateswaran, a surgeon who specializes in cataract surgery and corneal disease at Harvard-affiliated Massachusetts Eye and Ear.

Swapping lenses

Cataract surgery takes place in an outpatient surgery center. You're given medicine to relax you and keep your eye numb.

Your surgeon then makes a small incision in the eye, inserts tiny instruments, and breaks up and removes the cataract. (The surgeon may use ultrasound or laser technology to carry out these steps.) With the cloudy lens gone, the surgeon can place an artificial lens into the same space to give you clear vision.

Recovery can take up to four weeks. You'll have to use special eye drops during that time, and you'll need to avoid heavy lifting for at least a week.

Types of lenses

There are many choices for lenses to replace a cataract.

Monofocal lenses. These lenses give you the ability to see clearly at one distance point, which could be up close, at arm's length, or far away. You'll need glasses for the distances you don't choose.

"Let's say the person golfs and wants to see everything in the distance. We can set the lens for faraway vision," Dr. Venkateswaran says. "If the person is an avid reader and wants to look at material up close, we can focus the lens for close vision. We can also set the lens for intermediate vision, such as looking at a car dashboard or a computer."

If you need to have cataracts replaced in both eyes (surgery for each eye is performed weeks apart), you may choose to have a close-up focal point for one eye and a faraway focal point for the other. That combination, known as monovision, relies on the brain to adjust to the two distances so you can see both near and far.

Wider-range lenses. Some lenses help you see clearly at more than one distance. Multifocal lenses use two focal points; trifocal lenses have three; extended depth-of-focus lenses provide excellent intermediate and distance vision and some up-close vision. "Trifocal lenses have the most vision range, but they come with the risk of glare and halos at night. Extended depth-of-focus lenses work differently and have a lower risk of halos, but you may still need reading glasses, especially in dim light," Dr. Venkateswaran says.

Other lenses. Two other types of lenses to mention are toric lenses and the Light Adjustable Lens. Toric lenses correct astigmatism (blurred vision from an abnormally curved cornea — the outer "window" that protects the eye). Toric lenses are available in monofocal, trifocal, or extended depth-of-focus versions. The Light Adjustable Lens contains photosensitive material that can be altered using external ultraviolet light, and therefore allows adjustment of the focusing distance soon after surgery, if necessary.

Which lens is right for you?

Here are some tips to help you choose a replacement lens.

Think about your budget. Standard (monofocal) lenses and the surgery to implant them are covered by Medicare (you'll still have to pay your deductibles). For all other lenses, you must pay out of pocket for the lenses and surgeon fee. (Insurance usually covers the cost of the operating room and anesthesia,) Lenses and fees are offered in package deals, and they're not cheap. "You can expect to pay $1,500 to 2,500 per eye for a toric lens, $3,000 to $4,000 per eye for a wider-range lens, and $5,000 to $6,000 per eye for the Light Adjustable Lens," Dr. Venkateswaran says.

Tell your surgeon about your daily vision issues or needs. Do you like wearing glasses? Can you tolerate halos and glare at night? Do you read a lot? Do you do a lot of driving? Answering these questions can help you narrow your list of options.

Consider existing vision problems. "You need a certain amount of astigmatism to be a candidate for toric lenses," Dr. Venkateswaran says. "If you have eye disease, such as glaucoma or retinopathy, you may not be a candidate for certain premium lenses."

Make sure you understand the pros and cons. Getting a replacement lens is a big commitment, so learn as much as you can before making your selection. Your doctor will help you. "It's a lot like matchmaking," Dr. Venkateswaran says. "We want to find the right lens for you, and we don't want to change it later on."

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