Alessandro Arrigo, MD: Grading cataracts by the numbers

Cataract remains a leading cause of visual impairment worldwide and the most commonly performed surgical procedure, making accurate preoperative planning essential to anticipate surgical difficulty, avoid intra- and postoperative complications, and meet rising patient expectations for both visual acuity and visual quality.

Yet the most widely used grading tool, the Lens Opacities Classification System III (LOCS III), relies on subjective slit lamp assessment, and scores can vary between graders. At the 2026 European Society of Cataract and Refractive Surgeons (ESCRS) meeting, Alessandro Arrigo, MD, of IRCCS Ospedale San Raffaele and Vita-Salute San Raffaele University, Milan, Italy, presented a method that borrows a tool from retinal diagnostics to make cataract grading objective and reproducible.

Building on the physiology of the crystalline lens as the eye's principal blue light filter, Arrigo and colleagues hypothesized that age-related decline in that filtering capacity tracks with cataract severity and could be quantified using blue light autofluorescence confocal imaging. The team developed a standardized quantitative pipeline and three metrics—a morphological index and bright and dark energy indexes—then tested them in roughly 40 patients across cataract stages, with young cataract-free patients as reference. The indices correlated with LOCS III grades assigned by a single expert grader and with the signal-to-noise ratio of retinal imaging, reflecting the image degradation that denser cataracts impose on OCT and fundus autofluorescence. Arrigo frames the work, now under a second round of peer review and the subject of a patent, as a promising route to an objective classification system—one that could eventually incorporate artificial intelligence to refine its output.