This study is designed to evaluate patient-reported satisfaction and visual quality following bilateral cataract surgery with implantation of two different multifocal intraocular lens (IOL) strategies. The investigation compares a mixed-modality combination of complementary extended-depth-of-focus (EDOF) IOLs with a bilateral trifocal IOL approach. Although all lenses included in this research are CE-marked and commercially available, they differ in optical architecture and light-distribution profiles, offering an opportunity to assess whether pairing distinct optical designs between eyes can mitigate dysphotopsia while maintaining a full range of functional vision.
The scientific rationale derives from the known trade-offs associated with presbyopia-correcting IOLs. Trifocal designs distribute light to three focal points and provide distance, intermediate, and near performance, but may also induce photic phenomena such as halos or glare. EDOF platforms extend the depth of focus through controlled modulation of spherical aberration or wavefront shaping, with the goal of improving image continuity and contrast. The Mini Well and Mini Well Proxa lenses, which incorporate different wavefront-engineering profiles, are hypothesized to act synergistically when implanted contralaterally. This design may reduce dysphotopsia intensity by balancing light distribution asymmetrically across the visual system. In contrast, bilateral FineVision POD F implantation represents a uniform, widely adopted trifocal strategy.
The study is conducted at the Ophthalmology Unit of the Policlinico of Verona and enrolls 36 patients requiring routine bilateral cataract extraction. Participants are randomized 1:1 to one of the two treatment groups. The allocation sequence is computer-generated and concealed using a predefined method to ensure unbiased assignment. Masking is maintained at the patient level; patients are not informed of the IOL type they receive. Outcome assessors remain masked whenever feasible, although surgeons cannot be masked due to the nature of the intervention.
The protocol follows a standardized clinical workflow. Preoperative evaluation includes refraction, slit-lamp biomicroscopy, tonometry, retinal assessment, and biometric measurements using optical biometry to calculate IOL power. Cataract extraction is performed using a uniform phacoemulsification technique, with efforts to standardize incision size and capsulorhexis configuration. Postoperative care follows standard clinical practice and includes scheduled visits at early, intermediate, and late postoperative time points for both eyes.
Across follow-up, participants undergo routine ophthalmic assessments and standardized testing. At the final postoperative visit, patients complete structured questionnaires addressing visual function, satisfaction, spectacle independence, and visual disturbances. Objective quantification of dysphotopsia, including halo intensity and size, is also performed using validated halometry tools. These assessments provide combined subjective and objective characterization of visual quality.
The anticipated duration of participation is approximately four months, including preoperative evaluation, surgery for each eye, and postoperative follow-up through the three-month visit after the second eye procedure. Study data are collected in case report forms and stored under coded identifiers to ensure confidentiality. Data management follows applicable privacy legislation and good clinical practice guidelines. Quality assurance procedures include verification of source documents, consistency checks for questionnaire scoring, and calibration of devices used for optical quality measurements.
By comparing a contralateral EDOF-based strategy with bilateral trifocal implantation, this investigation seeks to clarify whether mixing complementary optical designs yields advantages in patient satisfaction, visual comfort, or dysphotopsia reduction. The findings are expected to contribute evidence relevant to presbyopia-correcting IOL selection, optimization of binocular optical planning, and patient counseling in cataract surgery.
