Monofocal Plus Finding the Balance

New enhanced monofocal intraocular lenses (IOLs) pro­vide a higher degree of functional vision than standard monofocal IOLs—without additional risk. The lenses are, therefore, promising candidates as the standard of care for cataract patients, said Filomena Ribeiro MD, PhD. 

She noted cataract patients generally receive some treat­ment for presbyopia, either in the form of multifocal specta­cles or contact lenses, or IOLs that offer varying degrees of multifocality or extended depth of focus. Both approaches have risks and benefits. In the case of the IOLs, there can be the risk of halos and dysphotopsias. For spectacles, there can be an increased incidence of falls. Multifocal spectacles contribute to one of three falls among the elderly, likely due to poor vision at intermediate distances.

A study of 40 cataract patients monitored with a Vivior headset over 36 hours showed activities involving intermedi­ate vision comprised around a third of their waking hours.¹ The evolution of multifocal and extended depth of focus (EDOF) IOLs has reflected an increased appreciation of the importance of intermediate distance vision: trifocals now direct 30% of light to the intermediate focus compared to less than 20% in some earlier models. 

The risk/benefit profile of multifocal and EDOF IOLS compared to standard monofocal IOLs is largely the compro­mise between spectacle independence and quality of vision. Enhanced monofocal IOLs aim to reduce that compromise to a minimum while providing around a line of additional intermediate visual acuity.

“What we really need is to find the best balance between functional vision and quality of vision for patients to perform all their daily activities,” Prof Ribeiro said. “If we increase a little bit the primary or secondary spherical aberration—or a mix of both—we can increase the depth of field, [providing] more intermediate vision without a perceived loss of quality of vision.”

The enhanced monofocal IOLs available today include the Tecnis^® Eyhance (Johnson & Johnson), the Isopure (BVI Physi­ol), and the RayOne (Rayner). The Eyhance combines negative spherical aberration with an increase of central curvature, the Isopure uses negative aberration customised top dioptric pow­er, and the RayOne uses positive spherical aberration. 

In the numerous studies published to date, enhanced monofocal IOLs showed a similar distance visual acuity and better uncorrected intermediate visual acuity compared to standard monofocal IOLs while providing similar contrast sensitivity and a similarly low incidence of halos and glare. On that basis, they could become the standard of care for cataract. Achieving that status will require agreement with regulatory bodies and support from professional organisa­tions with consensus statements based on scientific evidence, including clinical and patient-reported outcomes and cost-ef­fectiveness studies, Prof Ribeiro noted. 

“We still need more studies, but the trend is that in the near future, enhanced monofocals could be the new stan­dard of care.”

Prof Riberio presented at the ESCRS eConnect Webinar “Evi­dence-based overview of current premium IOL technologies.”

1. Ribeiro F, Ferreira TB, Silva D, Matos AC, Gaspar S, Piñero DP. “Analysis of Daily Visual Habits in a Presby­opic Population,” J Ophthalmol. 2023 Apr 8; 2023:6440954. doi: 10.1155/2023/6440954. PMID: 37089413; PMCID: PMC10118895. 

Filomena Ribeiro MD, PhD, FEBO is the head of the Department of Ophthalmology, Hospital da Luz, Lisbon, and President of the ESCRS. filomenajribeiro@gmail.com