Quentin B. Allen, MD, used to dread the typical “low light” conversations that would come up with many cataract patients. That conversation about how, even after corrective surgery, the patient would still experience difficulty settling into what should be their most relaxing moments, such as eating at a restaurant or reading before bed. It’s in these moments that patients are often reminded of how difficult it remains to read a menu or a best-selling novel without the need for additional bright lighting.

Today, these talks are far less cumbersome — mainly because of the advanced technology offered by the premium IOLs that he most commonly uses in surgery. Patients who meet certain criteria now have the ability to see with a larger, more natural range of vision and are less likely to struggle in these dim-lit moments, thanks largely to this class of premium IOLs. This assortment of lenses match advanced technologies to a variety of specific clinical needs to provide such patient benefits as presbyopia correction and astigmatism correction, enhanced contrast sensitivity, extended range of vision and overall better vision quality.

“While I still certainly need to counsel patients preoperatively and postoperatively that they will see better if they are in better light, difficulty with reading in low light is not an independent complaint that I hear much of anymore,” says Dr. Allen, a cataract and refractive surgeon at Florida Vision Institute, Stuart, Fla. “Now, even patients with relatively larger pupils will have better near vision than they’ve had with previous iterations of other multifocal lenses because of the larger sized (4.5 mm) central diffractive optic of the lens.”

It’s just one benefit that Dr. Allen and other surgeons have experienced with the latest premium IOL options on the market. Ophthalmology Management spoke with several providers about various lenses and steps taken to maximize the pool of patient candidates as well as the potential for positive outcomes during implantation of these IOLs.

RANGE OF QUALITIES & ENHANCEMENTS

PanOptix

The Alcon PanOptix trifocal IOL offers a natural full range of vision by splitting light more efficiently into more functional zones than other lenses, according to Dr. Allen. The result is better vision at all distances, not just while reading.

“Something was always sacrificed with previous lenses, but now we have a lens that has raised the bar high enough that there is minimal tradeoff to have a lens with this powerful technology,” he says.

Placing lenses with the same refractive target in both eyes is an added benefit and helps maximize visual summation and binocularity for potentially enhanced visual function.

“And that is where the PanOptix really shines, because instead of having to mix and match a low-add and a high-add power lens, or different focal points, now we can put the same lens with the same targeting in both eyes,” Dr. Allen says. “With other lenses, there can be very rigid focal points and significant gaps in the range of vision.”

TECNIS Toric II

Better low-light performance and clarity of distance vision are key benefits shared among patients who receive the TECNIS Toric II (Johnson & Johnson Vision), according to Karoline Rocha, MD, PhD, director of cornea and refractive surgery and associate professor in the Department of Ophthalmology at the Medical University of South Carolina in Charleston. Available in monofocal and multifocal models, TECNIS essentially eliminates spherical aberration as the lens with the highest compensation of aberration, Dr. Rocha says. “It’s -0.27 um for a 6-mm pupil size, and that gives patients the sharpest distance vision,” she says. “It also has the highest Abbe number at 55, which is generally important because the higher the number, the lower the chromatic dispersion and the induction of chromatic aberration.”

The ability to offer patients with pre-existing corneal astigmatism the improved uncorrected distance vision is also notable, but Dr. Rocha says she remains most impressed with the overall stability of the lens and its low rotation. “You don’t need to worry about this lens rotating postoperatively,” she says. “We’ve been conducting studies that measure the position of the lens post-op, and the refractive stability is very impressive. It’s also easier to offer patients with astigmatism the personalized vision — an extended depth of focus in the dominant eye and a multifocal diffractive bifocal in the non-dominant eye with regular astigmatism, because now we have a toric option.”

enVista

Stability is also a theme associated with the enVista platform of lenses (Bausch + Lomb), the “go-to” monofocal lens and monofocal toric lens for Audrey R. Talley Rostov, MD, a partner at Northwest Eye Surgeons in Seattle, Wash. “I really like the stability of the toric lens, which relates to the four-point stability in how it is manufactured,” says Dr. Rostov, who has been utilizing the enVista MX60E IOL and the toric MX60ET hydrophobic acrylic IOL since their respective inceptions in October 2017 and November 2019. “But what I really enjoy about this platform of lenses is that they are aberration-free and thus can be used in a variety of patients, including post-refractive surgery patients.”

Dr. Rostov also touts the toric’s neutral asphericity, which prevents profound changes in the patient’s vision if the lens gets decentered or tilted. “And the [step-vaulted AccuSet] haptics do not ‘join hands’ or become stuck together to where you have to tease them apart with another instrument,” Dr. Rostov says.

The eyelets at the optic-haptic junction of the MX60E and the MX60ET also allow for extensive interaction with the capsular bag to aid in securing lens position and may contribute to the overall stability of these lenses, says Francis Mah, MD, Scripps Clinic, La Jolla, Calif. “The capsule is able to not only go around the haptics in the IOL, but also possibly within the opening in the haptic; it just feels very stable in the eye,” Dr. Mah says. “Overall, the lens just looks solid in the eye. The lens material is stiffer, which makes it solid and resistant to scratches. And you can see the stability when it’s in the eye.”

The glistening-free optics also feature a StableFlex technology that allows the lens to open more quickly for the surgeon after implantation. “The MX60E and MX60ET versions open much faster, and I like that I can place it and be confident that it’s going to stay where I’ve placed it,” says Dr. Mah, citing optimal usage in patients who have had hyperopic LASIK because of their minus spherical aberration (SA). “Several excellent SA-correcting lenses correct for the natural plus corneal aspherical aberrations in the aging eye,” he says. “However, after hyperopic LASIK, the cornea has negative SA, so if you use one of these negative SA IOLs, you’re adding minus SA to what is already a minus SA cornea, which theoretically could lead to suboptimal vision. Therefore, the neutral SA MX60E and MX60ET will theoretically provide better quality of vision for these patients.”

PATIENT SCREENING & SELECTION

Optimizing outcomes potential

Recommendations for realizing the advantages of today’s premium IOLs and delivering on postop performance begin with competent screening for candidacy.

With the PanOptix, Dr. Allen says the lens performs particularly well in post-LASIK patients when three general parameters are followed: “You want a well-centered ablation with minimal high-order aberrations, a healthy ocular surface and reasonable, appropriate expectations,” he says.

To establish those expectations fairly, Dr. Allen believes it’s important that patients understand specifics about the technology and the clinical specifics of their eyes.

“Patients who have previously undergone LASIK are typically interested in visual quality, and they typically had excellent quality after LASIK,” he says. “But what they also have to understand is, because of that surgery, they may have a tendency for more aberrations in the optical system and that we will potentially add even more aberrations when we implant a multifocal lens over a prior refractive surgery cornea. These patients might also see more halos at night, which can be exacerbated by both the previous refractive surgery and by the multifocal lens.”

To illustrate this during cataract consultations, Dr. Allen shares images of pronounced multifocal that patients could experience as a worst-case scenario. Patients who are overly concerned with potential nighttime dysphotopsias may not be ideal candidates. Dr. Allen also believes this type of counseling is important for occupational night drivers, and he is hesitant about post-LASIK eyes because of the likelihood of preexisting dry eye, halos and glare from prior refractive surgery, which might be augmented by a multifocal lens.

Dr. Allen also says that lenses such as Vivity (see “Coming soon”), Symfony and Active Focus could be options for post-refractive patients because they split less light. “You need to have the conversation,” he says. “There are many ways to make post-LASIK patients happy, either with conventional monovision or toric monovision, or with a low-add multifocal.”

With the TECNIS Toric II, Dr. Rocha suggests a preoperative evaluation for patients with astigmatism to rule out irregular astigmatism or patients with keratoconus and corneal ectasia who likely may not be candidates for a toric lens. “It’s important to not only perform optical biometry but topography and tomography as well,” she says. “You also want to evaluate the ocular surface. If someone presents with dry eye, treat that prior to surgery and repeat the measurements prior to surgery. Also, it is important to rule out ‘dry-eye masquerade syndromes,’ which include epithelial basement membrane corneal dystrophy, conjunctivochalasis, Salzmann’s nodular degeneration and corneal scars — any corneal disease that can be causing irregular astigmatism.”

Along with not placing a toric IOL in patients with irregular astigmatism, Dr. Rocha advises to avoid a multifocal when retinal disease, advanced macular degeneration, moderate to severe glaucoma or Fuchs’ dystrophy are present. “During pre-op, make sure all measurements are reproducible, that you can measure the axis,” Dr. Rocha adds. “For multifocal and EDOF IOL cases, I usually add to my workup a macular OCT to rule out macular pathology.” These patients can benefit from a monofocal toric, she adds.

Dr. Rostov encourages use of the MX60ET in patients who have undergone any prior refractive procedure, especially if they have higher-order aberrations, because it’s very forgiving and aberration-free. “It’s also a benefit for patients with a little decentration from a previous LASIK or photorefractive keratectomy, and I’ve had success in patients after a cornea transplant or those with keratoconus,” she says. “Also, you want to optimize the ocular surface pre-op. If there’s untreated dry eye, you could be off by a diopter or more on your IOL calculation. If there’s a Salzmann’s or map-dot-fingerprint dystrophy that could be inducing astigmatism and it’s not treated beforehand, it’s going to come to haunt you because you may be off with your IOL calculation. All of these factors play a role for your biometry and your IOL calculations.”

As with any toric lens, Dr. Mah advises being mindful that cataract surgery is a refractive procedure. “So the goal of it, regardless if you’re using premium lenses, is to meet the patient’s expectations. If they want distance vision, for instance, try to reduce their myopia or hyperopia. For me, anyone over 0.75 D of astigmatism, I’ll discuss toric lenses and put them through the Barrett Toric Calculator. I try to correct as close to zero as possible, optimally with a little with-the-rule astigmatism. We’ve learned that, as people age, they progress towards, or increase against, with-the-rule astigmatism. So, leaving the patient with a touch (< 0.5 D) of with-the-rule may provide them with astigmatic correction for longer.”

Practice pointers

Clinically, surgical maneuvers can foster ideal outcomes with various lenses. Dr. Rocha takes a particular focus on the TECNIS Toric II platform. “You want to place the IOL with cohesive viscoelastic in the bag, then place the lens at the final axis,” she says. “Remove the viscoelastic behind the lens during irrigation and aspiration. The lens may move slightly, but it’s OK to then rotate back and place the lens at the final axis. If you need to rotate the IOL more than 2-3 clock hours, add cohesive viscoelastic to the capsular bag to rotate the lens — because you feel the resistance, as this lens is so stable. It is easier and safer to rotate the TECNIS Toric II platform with cohesive viscoelastic.”

Dr. Allen, who recently participated in a multicenter study that found 85% of patients using the PanOptix to report being completely spectacle independent, said that a few procedural steps could aid in these results. “I would target as close to plano as possible, and we verify with intraoperative aberrometry” he says. “With the first lens, I ideally want to be within -0.1 D to +0.1 D of plano. But the lens is very well tolerated anywhere between -0.25 D and +0.25 D outcome, and I’ve seen patients who have also done well at -0.5 D or +0.5 D.”

It is also important to control the astigmatism to under 0.5 D, Dr. Allen adds. “Over these levels of refractive error, patients will have a definite drop off in visual performance and a higher chance of requiring some sort of refractive enhancement,” he says.

From a stability standpoint, Dr. Mah says that there are some clean-up measures that can help improve this benefit of the toric IOLs, including the enVista.

“Making your capsulorhexis just under 6 mm to have 360-degree coverage of the anterior surface of the optic is important,” he says. “We want to be as clean and meticulous as possible, but I don’t clean all of the anterior cortical ‘dusting’ material from underneath the anterior capsule. It looks like it’s frosted, and it’s not like I leave cortex behind, but I believe the touch of cortical dusting adds a bit of ‘stickiness’ to the capsule so that the lens can have better adherence, at least until you get fibrosis. We want to remove all of the viscoelastic from the capsular bag, so going under the IOL or rocking the IOL back and forth to really get all the OVD out and maximizing IOL/capsule contact is critical. Finally, not leaving the eye over-inflated at the conclusion of surgery and making sure all the incisions are water-tight are important pearls for successful use of toric IOLs.” OM