Towards a Unified IOL Classification

A global consensus on simultaneous vision intraocular lenses (SVL) classification is an ambitious goal, and collaboration among everybody involved is pivotal. Experts gathered at the 2025 ESCRS Winter Meeting in Athens to discuss this topic during a TOGA Session, which placed panellists from all parties in a circle, as equals, in a modern version of the Greek agora.

Last year, the ESCRS Functional Vision Working Group, led by President Filomena Ribeiro MD, PhD, published an editorial in the Journal of Cataract & Refractive Surgery where they proposed an evidence-based new functional classification dividing lenses into two categories: partial range of field (ROF) and full ROF.^1,2 In turn, partial ROF IOLs can be divided into narrow (monofocal IOLs), enhanced (monofocal-plus IOLs) and extended (EDOF) range. Full ROF IOLs divide into continuous, smooth, and steep.

As Joaquín Fernández MD, PhD explained in the introduction to the TOGA Session, this proposed classification system is the result of a thorough analysis of 10 years of literature using statistical methods like cluster analysis and was not based on the working group’s opinion as experts.

“The key to global consensus is criteria, and this is a starting point. What could be the best way to reach consensus?” he asked the participants.

Francesco Carones MD, as President-elect of the American European Congress of Ophthalmic Surgery (AECOS) European Executive Committee, pointed out that collaboration between scientific societies is crucial, as a consensus on such classification can make interaction with companies and, above all, patients, easier.

“The classification must be scientific, driven by data, and easy [for patients] to understand, because if you get into too many details, they may be quite confused,” he said, adding it could also help overcome the language barriers in current IOL classifications.

However, classification is a step beyond mere nomenclature, as Professor Ribeiro underlined, emphasising that the result for patients is also important and the basis for continuing functional classification.

“We should couple this classification with patients’ reports about dysphotopsia, independence of glasses, and quality of vision. But the problem is the way we are reporting these outcomes now, because they are not yet standardised. And we need to do it,” she remarked. Prof Ribeiro noted the road ahead is still very long, and surgeons’ recommendations on what an IOL provides should focus on the patients rather than an optical bench or design.

Prof Fernández remarked that before producing a new functional classification, the ESCRS group published a standardised model explaining how to acquire and report data to create a strong systematic review and to craft something as a community. Now, there is a need for validated and standardised questionnaires to acquire other information for a subclassification beyond the depth of field.

This debate garnered plenty of participation from representatives of the industry. Speakers recognised industry collaboration and support as crucial in all this work. However, as Burkhard Dick MD, PhD commented, “Every IOL needs control trials, otherwise we cannot say that it is evidence-based.” In recent years, he added, some lenses came out without multicentre trials validating the results, something that needs to be changed.

Dr Carones raised another important issue about clinical studies: trials need to be conducted in hospital and university settings more often, where patients do not have expectations based on cost.

“I am urging this organisation to consider doing both arms of studies, in public hospitals and private practices, because, in the latter, you have the real-world experience of patients,” he said.

All the attending industry representatives pointed out that manufacturers are obliged to supply some evidence of their products before releasing them on the market. However, they recognised the importance of having this classification as a common language and as a benefit to everybody, from surgeons to patients all over the world. They praised the ESCRS for the effort, making themselves fully available for future collaborations.

An interesting perspective came from Sorcha Ní Dhubhghaill MBBCh, PhD, who spoke as a surgeon in university hospital settings. “Typically, we are not the best clients for these lenses, but since I have started to implement this simplified classification, I have noticed two things: first, patients started to understand the benefits of lenses other than standard monofocal; second, residents, who have everything to learn and no time, find this approach good to understand what these lenses can do,” she said.

Finally, Prof Fernández pointed out that the working group does not want this classification to complicate things, especially for industry. “The idea is to give the best information to our patients, and to give you an easier and fairer way to compare and transmit evidence and escape the market-oriented fight we are seeing right now,” he concluded.

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

Joaquín Fernández Pérez MD, PhD is based at Qvision, Department of Ophthalmology of Vithas Almería Hospital, Spain. joaquinfernandezoft@qvision.es

Francesco Carones MD is medical director and physician CEO of Advalia-Carones Vision in Milan, Italy. fcarones@carones.com

H Burkhard Dick MD, PhD, FEBOS-CR is professor and chairman of the Ruhr University Eye Hospital in Bochum, Germany, and ESCRS president elect. dickburkhard@aol.com

Sorcha Ní Dhubhghaill MBBCh, BaO, PhD, Dip(stats), FEBO, FEBOS-CR, MRCSI(ophth) is Head of Department, Ophthalmology, at the Brussels University Hospital (UZ Brussel), Belgium. sorcha.ni.dhubhghaill@uzbrussel.be

1. Ribeiro F, et al. “Evidence-based functional classification of simultaneous vision intraocular lenses: seeking a global consensus by the ESCRS Functional Vision Working Group,” J Cataract Refract Surg, 2024 Aug; 50(8): 794–798.