A new IOL combines the advantages of diffractive multifocal and extended-depth-of-focus lenses, providing a natural range of vision.
In a recent prospective case series, my colleagues and I evaluated 3-month outcomes in 27 patients undergoing bilateral implantation of the ZFR00V lens (Tecnis Synergy, Johnson & Johnson Vision).1 This new IOL combines the advantages of diffractive multifocal and extended-depth-of-focus (EDOF) IOLs.
Like other EDOF lenses, the elongated focus provides a more natural range of vision while minimising dysphotopsia symptoms; however, because it also has diffractive optics like multifocal IOLs, the hope was that this lens would improve near vision over EDOF lenses. Our study suggests that these goals have indeed been met.
Patients were followed at 1 day, 1 month and 3 months after surgery. Uncorrected and distance-corrected visual acuity was measured under various lighting conditions at far, intermediate (66 cm) and near (40 cm). Quality of vision, visual symptoms, satisfaction and spectacle independence were reported by patients via questionnaires at 3 months.
Defocus curves were also generated at the 3-month visit. The study was conducted prior to the availability of the toric version of this lens, so all patients had ≤0.75 D of astigmatism preoperatively.
At 3 months, under photopic conditions, the mean monocular uncorrected distance acuity was 0.04 logMAR; mean uncorrected intermediate was 0.04 and mean uncorrected near was 0.05. Distance-corrected acuity was 0.03 and 0.00 at intermediate and near, respectively.
Under mesopic conditions, distance-corrected acuity was −0.01 for distance and 0.07 for near (Table 1). Uncorrected distance acuity of 20/32 (0.20 logMAR) or better was achieved by 96% of patients.
These distance results are better than those reported for multifocal IOLs in several published papers.2,3 Our results were better at intermediate and near than the FineVision trifocal,4 and better at near than the PanOptix trifocal or the combination of Tecnis Symfony/ZMB00 lenses.5 The near vision is significantly better than has been reported with Tecnis Symfony, with similar intermediate and distance results.6
It was exciting to see that patients did not lose distance vision in mesopic lighting conditions, as this has historically been a weak point for multifocal IOLs. The defocus curve was broad and smooth, demonstrating that the IOL provides 20/40 (0.30 logMAR) or better vision from +1.00 to −4.00 D and 20/25 (0.10 logMAR) or better from +0.05 to −3.00 D.
At 3 months, none of the patients reported using spectacles for distance and 96% were totally spectacle independent at all distances. One patient (3.7%) said he used glasses for near and occasionally for intermediate.
Although some patients experienced glare, halo or starbursts, as we would expect with diffractive optics, no patient rated their night vision symptoms as “severe” or “very bothersome”. Eighty-nine per cent of patients were fairly to very satisfied with their vision.
We have come to expect an inverse relationship between near vision and nighttime quality of vision. Typically, with multifocal IOLs, better near vision is associated with higher rates of dysphotopsia, but we did not find that to be the case with this lens.
In my practice, this new lens has expanded the pool of candidates for presbyopia-correcting IOLs to include those with very high near demands. In the past, low to moderate myopes who remove their glasses to read and hyperopes who are accustomed to a large magnification for near have been very difficult to satisfy with presbyopia-correcting IOLs.
Those who are short in stature or have short arms also demand very close near vision that has been hard for us to provide. Because of its EDOF range from near to intermediate, this lens can satisfy these patients, as well as those who prefer a more traditional near point.
In fact, the lens’s wide range for near vision means that patients do not need to experiment to find the best distance to hold their phone or the newspaper – they can just read at their normal distance. That has reduced the amount of time I need to spend on patient education and handholding after surgery and increased the proportion of happy faces I see at follow-up visits.
The good acuity and quality of intermediate vision is also extremely important to me. Intermediate vision tends to be an afterthought for clinicians because it is not a standard part of our exam in the way that distance and near acuity are. However, the reality is that much of our patients’ lives happen at intermediate range.
As with any lens that incorporates diffractive technology, we should exclude patients as candidates for this lens if they have any other ocular pathology, such as glaucoma or macular issues. Surgeons implanting the new IOL should target emmetropia rather than mini- or micro-monovision, as some have done with other presbyopia-correcting IOLs, to ensure good near vision.
In fact, a myopic result risks compromising distance acuity, so I generally aim for the lowest positive predicted refraction (closest to plano). Additionally, my personal preference for this and all presbyopia-correcting IOLs is bilateral implantation.
With neuroadaptation and binocular summation, we see further gains in vision and satisfaction at 3 and 6 months with these advanced IOLs, compared to largely unchanged vision at that point after monofocal IOL implantation. This is a welcome new addition to the expanding portfolio of presbyopia-correcting IOLs.