Even though bifocal multifocal IOLs offer a dramatic breakthrough in providing improvement in both near and distance vision, intermediate vision has become increasingly more important. In terms of performing tasks on a computer, tablet or smartphone, seeing well in this zone is paramount. Patients want to continue to participate in hobbies and sports like golf, tennis and swimming, for example, that demand a more natural range of vision. They may not know what intermediate vision is, but they understand that they need to see clearly to do what they want every day.

With trifocality, surgeons can offer distance, intermediate and near vision with one IOL. Published reports of experience outside the United States indicate high levels of both spectacle freedom and patient satisfaction with available implants. As a result of these outcomes and now years of experience, trifocals outpace multifocal technology in the overseas market, according to information available from data research groups worldwide like Market Scope, Nielsen, Euromonitor and others. Surgeons are becoming more confident that emerging trifocal platforms can deliver on the promise of a fuller range of high-quality vision with fewer troublesome dysphotopsias.^1-6

Here’s what you need to know about trifocal IOLs.

WHAT IS TRIFOCALITY?

Standard trifocal implants are predicated on the concept of providing three focal points for distance, middle and near vision by adding two additional step heights to the diffractive ring to achieve the intermediate range. The optical principles of adding those different step heights result in an intermediate visual range at about 80 cm, or 32 inches.⁷ Unfortunately, in everyday life, this is really a little too far. For example, according to the Occupational Safety and Health Administration, the ideal range for a computer monitor is 60 to 67 cm, making this intermediate range too far to be useful.

WHAT IS THE PANOPTIX, AND HOW DOES IT WORK?

In the United States, Alcon’s AcrySof IQ PanOptix is the only FDA-approved trifocal implant. The PanOptix is different from the other trifocals because it acts as a quadrifocal lens by providing four focal points using three step heights in the diffractive ring. In addition to distance vision, this gives three focal points at approximately 120 cm, 60 cm and 40 cm for near.⁷

WHAT ABOUT VISUAL QUALITY AND DISTURBANCES LIKE GLARE AND HALO?

Splitting light four ways theoretically allots just 25% of available light to each range, thereby causing a loss of contrast sensitivity plus increased nighttime dysphotopsias. With the PanOptix, one of the three step heights is truncated, sending those light rays for distance vision. With 50% of available light contributing to distance vision, acuity and contrast sensitivity are preserved, and patients experience less incidence of nighttime dysphotopsias (ie, rings, halos, cobwebbing) compared with what has been reported for other diffractive and extended depth of focus (EDOF) lenses.⁸ That leaves 25% of available light for a more functional intermediate range (60 cm) compared with other technology and a great near range at 40 cm.

Traditionally, diffractive optics employed by multifocals — whether bi, tri or quad — become increasingly pupil dependent, causing patients to struggle with contrast sensitivity in low light.⁸ The PanOptix has a 4.5-mm diffractive zone, making it less dependent on pupil size and lighting conditions. In my experience with this lens, patients are largely spectacle free and their quality of near intermediate range vision is preserved.

The unique design solves the problems mentioned above that clinicians have noticed with some trifocals; these improvements are why this lens has quickly become a favorite across Europe and is set to be a satisfying lens for U.S. patients.

HOW DO YOU DETERMINE CANDIDATES?

As usual, surgeons must follow key principles determining a patient’s candidacy for advanced-technology implants. Patients must be educated to have reasonable expectations, as always, setting the bar low and delivering high. Evaluating ocular surface disease (OSD), and treating it if found, is required to ensure accurate biometry, and surgeons need to assess for macular pathology, check pupil size and establish angle kappa.

In addition, I tell patients that they should initially expect to see halos and rings around headlights and streetlights at night. Because patients are so pleased with their range of vision and they are prepared to expect some visual effects, I have found their neuroadaptation process to be speedy.

HOW DO YOU TALK TO PATIENTS ABOUT THEIR OPTIONS?

Having another lens option has simplified my patient conversations. Essentially, multifocal bifocal lens implants or EDOF lenses require some customization to overcome the technology’s shortcomings, making patients choose their least important range. The PanOptix, though, covers the whole board, so to speak, like a chess game.

Most patients, especially those who are at active cataract and clear lensectomy age, put priority on not just distance or intermediate or near vision — they need all three distances, and under variable lighting conditions. Instead of a conversation about which range of vision is most important, it’s more about identifying patients who want to minimize wearing glasses.

Before the PanOptix, my presbyopia-correcting lens volume was 25% to 30% of the total, a credit to the array of available lenses and surgical advancements. Adding the implant has brought that overall percentage closer to 40%, in part due to my increasing confidence in clear lensectomy outcomes.

WHAT RECOMMENDATIONS DO YOU HAVE WHEN STARTING WITH TRIFOCALS?

Certainly, when surgeons start using this lens or any new advanced-technology IOL, I recommend a case of uncomplicated cataracts with no other pathology, OSD or prior refractive surgery. I have, however, started using the PanOptix with increasing confidence in postrefractive patients. Based on its optics, I have found the lens to be more forgiving than other types of presbyopia-correcting IOLs. A patient who has had previous myopic LASIK, for example, can end up as much as 0.50 D hyperopic and still have excellent distance vision, great intermediate and good near.

WHAT TOOLS DO YOU USE FOR CALCULATIONS?

I use the Barrett calculator for lens selection in most patients, with either Barrett True K or the Haigis-L for postrefractive eyes. I tend to do the nondominant eye first, aiming for the lens closest to plano targeting.

In the dominant eye, I aim for the lens closest to plano targeting even if it means favoring hyperopia. For example, if choosing between a lens targeted at -0.30 D and a lens targeted at +0.20 D, I choose the latter. Importantly, this is unlike other lenses, where surgeons tend to err on the side of myopia.

DO YOU HAVE ANY SURGICAL TIPS OR TRICKS OF NOTE?

For patients with a high angle kappa (generally greater than 0.6 mm, although there is much more forgiveness with the PanOptix), I ensure the lens is centered on the visual axis and not as much about pupillary centration. I check this intraoperatively using the second Purkinje reflex as the patient fixates on the light. Postoperatively, if I see that the lens is decentered from the photopic pupil, I can correct for that using an argon laser. This will serve to lightly contract the pupil at the midperiphery and shift the centration of the pupil toward the lens. I can center it on the mires or the rings of the lens, which will reduce nighttime dysphotopsias.

The PanOptix is available in a toric, so for patients with moderate amounts of regular astigmatism, I can still offer the technology and achieve the same outcome. Historically, the AcrySof material offers fantastic rotational lens stability over time.⁹ Unless proven otherwise, I consider virtually all my patients a refractive cataract patient and a candidate for this lens.

WHAT’S NEXT IN TRIFOCAL IOLS?

It is an exciting time in implant technology, with the industry’s leading manufacturers poised to help further refine lens platforms for patients. Surgeons will be even more empowered to customize outcomes that deliver the quality and range of vision that meets patients’ visual lifestyle. Bausch + Lomb’s enVista MX60EF trifocal is in U.S. clinical trials,¹⁰ as is Johnson & Johnson’s hybrid version of the technology, Symfony Plus.¹¹ (See “Trifocality in the U.S. pipeline,” above). Outside the United States, surgeons are using a range of additional trifocal implants, most commonly AT LISA (Carl Zeiss Meditec) and FineVision (PhysIOL).

CONCLUSION

Even though the trifocal era has only just arrived in the United States, the PanOptix IOL can still be thought of as a next-generation trifocal. When surgeons continue attending to the essential preoperative considerations, like OSD and macular pathology, this technology can achieve optimized outcomes for many patients. The importance of setting expectations appropriately never changes, and surgeons should continue to underpromise and overdeliver, even when using this new technology.

There is no such thing as any one perfect lens for every single patient. Today, however, the PanOptix is the right choice for a broad swath of patients in my practice. The lens has been specifically created to address pitfalls with other designs. In my experience, it offers the best match to patients’ daily visual lifestyle. OM

REFERENCES

1. Al-Khateeb G, Shajari M, Kohnen T. Intraindividual comparative analysis of the visual performance after cataract surgery with implantation of a trifocal and a bifocal intraocular lens. J Cataract Refract Surg. 2017;43:695-698.
2. Alió JL, Plaza-Puche AB, Alió Del Barrio JL, et al. Clinical outcomes with a diffractive trifocal intraocular lens. Eur J Ophthalmol. 2018;28:419-424.
3. Cochener B, Vryghem J, Rozot P, et al. Clinical outcomes with a trifocal intraocular lens: a multicenter study. J Refract Surg. 2014;30:762-768.
4. Cochener B, Boutillier G, Lamard M, Auberger-Zagnoli C. A comparative evaluation of a new generation of diffractive trifocal and extended depth of focus intraocular lenses. J Refract Surg. 2018;34:507-514.
5. Kaymak H, Breyer D, Alió JL, Cochener B. Visual performance with bifocal and trifocal diffractive intraocular lenses: a prospective three-armed randomized multicenter clinical trial. J Refract Surg. 2017;33:655-662.
6. Mencucci R, Favuzza E, Caporossi O, Savastano A, Rizzo S. Comparative analysis of visual outcomes, reading skills, contrast sensitivity, and patient satisfaction with two models of trifocal diffractive intraocular lenses and an extended range of vision intraocular lens. Graefes Arch Clin Exp Ophthalmol. 2018;256:1913-1922.
7. Gatinel D, Loicq J. Clinically relevant optical properties of bifocal, trifocal, and extended depth of focus intraocular lenses. J Refract Surg. 2016;32:273-280.
8. Sudhir RR, Dey A, Bhattacharrya S, Bahulayan A. AcrySof IQ PanOptix intraocular lens versus extended depth of focus intraocular lens and trifocal intraocular lens: a clinical overview. Asia Pac J Ophthalmol (Phila). 2019;8:335-349.
9. Lee BS, Chang DF. Comparison of the rotational stability of two toric intraocular lenses in 1273 consecutive eyes. Ophthalmology. 2018;125:1325-1331.
10. Evaluate the safety and effectiveness of the enVista one-piece hydrophobic acrylic trifocal intraocular lens. ClincalTrials.gov. https://clinicaltrials.gov/ct2/show/NCT03603600 . Accessed Dec. 22, 2019.
11. A comparative study of TECNIS Symfony Plus IOL and a Trifocal IOL. https://clinicaltrials.gov/ct2/show/NCT04156737 . Accessed Dec. 22, 2019.

About the Author

Neel R. Desai, MD, is director of Cornea, Cataract, and Refractive Services at The Eye Institute of West Florida; medical director, Lions Eye Institute for Transplant and Research; and president and CEO, Clarity Visionary Consulting, all located in Tampa, Florida.

Disclosures: Dr. Desai is a consultant to Alcon, Bausch + Lomb and Johnson & Johnson Vision.