Busting Some Myths Around Presbyopia-Correcting IOLs

New technologies make a lot of older worries about presbyopia-correcting IOLs obsolete.

By Sondra Black, OD

In talking with optometrists around the United States and Canada, I often hear negative feedback from individuals who recommended multifocal IOLs to their patients for presbyopia correction years ago, during the first generation of those lenses. Some of their patients had bad experiences, and these optometrists say they have sworn off the category ever since.

But so much has changed since then. With the introduction of lower-add multifocal IOLs and extended depth-of-focus (EDOF) IOLs, it is worth revisiting how presbyopia correction at the time of cataract surgery can benefit your patients. This article addresses five myths about presbyopia-correcting IOLs.

Myth No. 1:
“My patients don’t want to deal with the night vision problems.”

With some of the early multifocal IOLs, almost 20% of patients experienced severe postoperative glare and halo. But as optics have been refined and add powers reduced, the out-of-focus component of the image has become much less problematic. With today’s IOLs, dysphotopsia symptoms are milder, and they usually go away after the first month (Figure).1 I estimate that about 5% of our lifestyle lens patients have some glare and halo that persists beyond the first month, and probably only 2% are really bothered by glare and halo.

Myth No. 2:
“They just aren’t worth the risk.”

Some optometrists feel that any risk of night vision problems, poor contrast, or reduced quality of vision just is not worth it. Again, the risks are significantly lower now than in the past. Traditional multifocal IOLs split incoming light in such a way that transmission to the retina is somewhat diminished. The Tecnis Symfony (Abbott) EDOF lens works quite differently, elongating the focus rather than splitting light between near and distance focal points. And because the lens corrects spherical and chromatic aberration, eyes implanted with the Symfony have contrast acuity similar to that in eyes implanted with a monofocal IOL.

We also have to consider the reward side of the risk:reward ratio. Without a presbyopia-correcting IOL, there is a 100% chance your patient will still be presbyopic postoperatively. And patients find presbyopia really bothersome. Many of my patients in their 60s and older are still working and active, they use their digital devices all the time, and they are definitely trying to fight the aging process. Reading glasses, to them, are an unwanted sign of age. It is always important to give these patients the multifocal option. We can’t assume that they will not be interested.

Figure. Most patients with EDOF lenses had no to moderate visual symptoms.

Myth No. 3:
“Presbyopia-correcting IOLs don’t live up to patient expectations.”

It is true that we cannot give patients 20-year-old eyes. However, newer IOLs do a much better job of meeting patients’ visual needs. Traditional multifocal IOLs have a near-vision focus at about 33 cm, which is much too close for everyone except people with short arms and hobbies such as crocheting. Low-add multifocal IOLs and EDOF lenses provide excellent acuity at the 40-to-50-cm distance that is commonly used for computers, smartphones and tablets, and most everyday tasks (Table).

Additionally, the Symfony EDOF lens gives patients more natural vision. They can get closer to or further away from objects and continually see them, with no drop off from one distance to the other. I liken this to the difference between a flat-top bifocal and progressive spectacles, although EDOF lenses do not have the intermediate distortions that are inherent in progressive spectacles.

There is no doubt that each patient’s expectations must be discussed before surgery. High myopes, even with the best of lenses, will lose that extremely close working distance that they have had all their lives when they removed their glasses. This loss must be addressed before surgery. The -10.00 D patient that has been used to perfect vision at 6 inches will need to be counselled that they will lose that distance. It is quite a shock for them otherwise.

Myth No. 4:
“My postLASIK patients aren’t candidates.”

In the past, most surgeons did not recommend multifocal IOLs for patients who had previously undergone corneal surgery, especially those who had radial keratotomy or LASIK in the early days, due to the presence of corneal aberrations and the increased unpredictability of IOL power calculations in these eyes. But EDOF lenses can work well for these patients. They provide high quality vision similar to that with a monofocal IOL, and they are forgiving of residual refractive error. Postrefractive surgery patients are in many ways the perfect candidates because they have already demonstrated a willingness to undergo surgery and to pay for the refractive outcomes they want. My post-LASIK husband underwent cataract surgery last year, and he is now very happy with his bilateral EDOF lenses (see Case Report).

Myth No. 5:
“IOL selection isn’t my job. I just refer the patient and let the cataract surgeon do the rest.”

As optometrists, our input regarding patients’ visual needs and our role in educating patients are absolutely critical. The surgeon has a few minutes with the patient, while we may have years or decades of experience with that patient and his or her lifestyle, expectations, and ocular history. Here is a common scenario:

Surgeon: “What do you want from your vision after surgery?”

Patient: “Oh, I’d love it if I didn’t have to wear glasses to drive.”

Surgeon: “Ok, we can do that.”

And the surgeon plans to implant a monofocal IOL for distance. The patient should be happy, right? Perhaps. But maybe that -2.50 D patient used to take her glasses off to read and did not understand that she would no longer be able to do that. Postoperatively, she needs to carry around reading glasses, has to use them continuously even to see who is calling her cellphone and is absolutely miserable. Maybe the surgeon even mentioned “reading glasses,” but the patient heard only “reading” and did not understand that she would also need glasses to see her food in a restaurant, apply makeup, shop, or use the computer.

CASE REPORT: CATARACT SURGERY WITH BILATERAL EDOF LENSES

History and Examination
The patient is a male professional musician (Figure 1) who drives a lot at night and must be able to read music at an intermediate distance in dim light. He has a history of previous LASIK, but his topographies (Figure 2) show well-centered ablations. His corneas are more than 480 μm thick.

Surgery and Results
The patient underwent cataract surgery (Figure 3) with implantation of Tecnis Symfony ZXR00 (Abbott) IOLs in both eyes. One year postoperative, his uncorrected visual acuity at distance and intermediate is 20/20, and uncorrected near visual acuity is 20/15. He reports no problems with night driving.

Figure 1. The patient is a professional musician—and the author’s husband.

Figure 2. Topographies in the right (A) and left (B) eyes show well-centered previous LASIK ablations.

Figure 3. EDOF lenses were implanted in both eyes.

TALK THROUGH THE OPTIONS

It is much less stressful for patients if they have had a good, thorough discussion with their optometrist, talking through the options before they have to make decisions at the surgery center.

I strongly believe that we can best serve our patients by providing them with guidance before cataract surgery; however, that guidance has to be based on knowledge of the latest IOL technologies. Talk to the surgeons you refer patients to. Develop a strong rapport with them. Understand which lenses they use and why, and commit to working more closely with them to obtain the best results for your patients.

1. Tecnis Symfony Extended Range of Vision IOL [package insert]. Santa Clara, CA: Abbott; 2016

Sondra Black, OD
• Vice president and clinical director, Crystal Clear Vision, Toronto, Canada
sondra.black@crystalclearvision.com
• Financial disclosure: consultant to Abbott