Peering into the Future of IOLs: Enhanced Monofocals to Refractive EDOF Designs

From purely refractive EDOFs to enhanced monofocals, this session explored new-generation IOLs, offering practical insights into optical design, patient selection and visual quality trade-offs.

From the familiar to the futuristic, Saturday’s session What’s New in IOLs? offered delegates a well-charted course through the evolving world of intraocular lens (IOL) technology. Chaired by Prof. Hungwon Tchah (South Korea) and Dr. Rohit Om Parkash (India), the session was helmed by seasoned leaders navigating the tides of innovation in presbyopia correction.

Attendees were treated to a high-definition lineup of IOL experts showcasing real-world results, surgical strategies, and early clinical experiences with enhanced monofocal, refractive EDOF, and trifocal lenses. For those looking to sharpen neuroadaptation, curb dysphotopsia, or steer confidently into mix-and-match implantation, this session offered a recalibrated lens on where premium cataract surgery is headed next.

Reading between the lines (of Kanji)

Prof. Hiroko Bissen-Miyajima (Japan) opened the session with a look at PCIOL adoption in Japan, where both clinical value and patient cost play a role. Monofocal and enhanced monofocal lenses are covered by national insurance, but patients must pay an additional USD $2,000–3,000 per eye for presbyopia-correcting options. Overall national uptake remains under 5%, though some clinics report 50–80% usage.

Despite the cost barrier, clinical outcomes speak volumes. Both extended and full-range PCIOLs deliver strong distance and intermediate acuity, with full-range lenses offering better near vision and a broader defocus curve. “In Japan, full range type is the most preferred PCIOL—patients value near vision for reading kanji more than they worry about halos,” she noted.

Extended depth designs are still a strong option for patients sensitive to photic phenomena, with high contrast sensitivity and indications that include post-LASIK eyes and mild retinal disease. Growth has been slow, but the tide may be turning, one kanji character at a time.

The pinhole that packs a punch

Dr. Robert Ang (Philippines) brought the spotlight back to small-aperture IOLs: a technology that traded corneal inlays for intraocular precision. Small-aperture intraocular lenses utilize the pinhole effect to extend the depth of focus and filter higher-order corneal aberrations. “Maybe in some cases, aberration filtering is the main effect—and presbyopia correction only secondary,” he noted.

In long-term data (>5 years), monocular implantation achieved good distance and intermediate acuity in 92% of patients, with 60% reaching functional near (J3). Binocular cases delivered 20/25 or better across all distances. Outcomes were consistent in virgin eyes, post-LASIK/RK/PRK cases, and even post-inlay cataract patients.

With minimal photic symptoms and a durable black mask containing 8,000 microperforations, this lens proved its staying power. For eyes that color outside the optical lines, the small-aperture IOL may be less about restoring youth and more about restoring order.

Fighting fog with rabbits

Hydrophilic acrylic IOLs are valued for their flexibility and biocompatibility, but are susceptible to anterior surface calcification over time. Prof. Hiroyuki Matsushima (Japan) shared early-stage findings from a rabbit model evaluating a potential fix. His team applied methylation surface treatment (MLS) to reduce carboxylic groups, which are the prime suspects in calcium phosphate binding.

After six months, untreated lenses showed visible calcium buildup on the anterior surface, while the MLS-treated group stayed significantly clearer. “Methylation treatment of the hydrophilic acrylic IOL surface could inhibit calcium deposition,” Dr. Matsushima reported.

Posterior calcification remained minimal in both groups, suggesting the front surface is the key battleground. While the findings are still preclinical, they hint at a promising strategy for prolonging clarity in hydrophilic designs. More testing is needed, Dr. Matsushima cautioned, but if lens manufacturers want to keep their edge, keeping cloudiness at bay might require a little surface-level chemistry.

Modest monovision for modern lifestyles

Dr. Han Bor Fam (Singapore) delivered a practical guide to modest monovision strategies using monofocal plus, diffractive EDOF and refractive EDOF lenses. In his approach, the dominant eye is corrected near emmetropia for distance, while the fellow eye is adjusted slightly myopic for near.

“With monofocal plus, I need modest monovision of about 1.5 D to give me 40 to 50 cm,” he shared. Diffractive EDOFs typically required just 1.0 D, while refractive EDOFs performed well with –0.5 to –0.75 D, aided by strong binocular summation.

Dr. Fam emphasized that enhanced lens designs allow surgeons to skip old-school contrast dominance tests and achieve more predictable outcomes. For patients with precise near needs (think: jewelers, seamstresses or surgeons) he may still push toward “near monovision,” but for most, modern IOLs make minimal offset go a long way.

Toric tactics to combat misalignment

Toric IOLs can drift off course postoperatively and without careful checks, even “satisfied” patients may carry residual astigmatism. Dr. Tsutomu Ohashi (Japan) shared how wavefront analyzers have become his go-to compass for realigning these lenses.

Unlike anterior segment OCT, which sometimes gives ambiguous results, the wavefront analyzer overlays the corneal steep axis and IOL axis in a single, color-coded map that makes mismatches easy to spot. “It provides objective confirmation of the IOL position and the corneal axis,” he explained.

In two clinical examples, repositioning based on wavefront guidance reduced residual astigmatism from –2.5 D to –0.25 D and from –2.0 D to –0.75 D. Across 1,600 toric IOL cases in five years, only 51 needed correction, but the results showed that mean misalignment dropped from 14° to 4° and residual cylinder was halved.

The refractive sweet spot

Prof. Hungwon Tchah (South Korea) shared early results with the PureSee IOL (Johnson & Johnson Vision, Florida, United States), a purely refractive EDOF lens designed to minimize dysphotopsia while delivering monofocal-like clarity across distances.

Unlike hybrid or diffractive optics, PureSee uses an aspheric front and a refractive gradient on the posterior surface to generate an elongated focus range. In 28 eyes, 97% achieved ≥20/32 intermediate and 80% reached ≥20/40 near, with a smooth defocus curve extending to 33 cm. Patient-reported outcomes were equally strong: 88% noted no or minimal photic phenomena, and 100% had minimal halos.

Compared with Symfony, PureSee performed better at near with fewer side effects. A standout case showed that targeting –0.75 D enhanced near vision without sacrificing distance. “The PureSee IOL provides excellent distance and intermediate vision with very low dysphotopsia,” Prof. Tchah noted. He emphasized that mild myopic targets may offer particular benefits for Asian patients with high near-vision expectations.

Same platform, different priorities

Prof. Myoung Joon Kim (South Korea) explored the nuanced distinctions between two popular lenses from Johnson & Johnson Vision: PureSee and Eyhance. While both share the same platform, their optical strategies diverge. PureSee, a refractive EDOF IOL, uses a blend of spherical aberrations to elongate the focal range, delivering stronger intermediate and near acuity. Eyhance, an enhanced monofocal, offers a milder boost to intermediate vision but excels in stability, especially in eyes with irregular corneas.

Defocus curves show Eyhance peaking around 66 cm, while PureSee extends further at the cost of slight distance acuity compromise. Case studies reinforced this: PureSee struggled in post-LASIK eyes with asymmetric aberrations, while Eyhance performed more predictably.

By ANSI standards, PureSee qualifies as an EDOF lens and Eyhance does not. “PureSee provides better intermediate acuity,” Prof. Kim said, “but it’s less forgiving in eyes with comorbidities or irregular corneas.” For surgeons, the choice comes down to the patient profile, not platform.

Fine-tuning the focus

From spherical aberration balancing acts to full-spectrum platform comparisons, this session brought clarity to the next generation of lens technology. As Prof. Kim reminded us, even upgrades come with trade-offs. But when armed with optical insight, clinical nuance and a healthy respect for ocular surface optimization, surgeons are better equipped to tailor outcomes and meet the growing demand for spectacle independence without losing sight of patient satisfaction.

Editor’s Note: The 37th annual meeting of the Asia-Pacific Association of Cataract and Refractive Surgeons (APACRS 2025) is being held from 21-23 August in Ahmedabad, India. Reporting for this story took place during the event. This content is intended exclusively for healthcare professionals. It is not intended for the general public. Products or therapies discussed may not be registered or approved in all jurisdictions, including Singapore.