Prospective, Randomized, Parallel-group Comparison of Two Refractive EDOF Intraocular Lenses: Johnson & Johnson Tecnis PureSee Versus 1stQ Comfort Z-EDOF (1stQvsPureSee)

Background and rationale: Extended depth-of-focus (EDOF) intraocular lenses (IOLs) extend the range of functional vision beyond that of conventional monofocal IOLs by modifying the eye's wavefront to create an elongated focal range, while aiming to limit the photic phenomena (halos, glare, starbursts) often associated with multifocal IOLs. Different EDOF platforms use fundamentally different optical strategies, yet direct comparative evidence between EDOF designs from prospective randomized trials is limited; most published studies compare an EDOF IOL with monofocal or multifocal lenses rather than with another EDOF design. This trial provides a head-to-head comparison of two purely refractive EDOF platforms that employ different optical principles: the Tecnis PureSee (Johnson & Johnson Vision), a refractive EDOF design with a continuous power profile and negative spherical aberration, and the 1stQ Comfort Z-EDOF (1stQ GmbH), a refractive aspheric EDOF design with a modified spherical aberration profile.

Design: This is a single-center, prospective, randomized, parallel-group comparative study conducted at the Department of Ophthalmology, Klinik Hietzing, Vienna, Austria. Patients undergoing bilateral cataract surgery are randomized 1:1 to receive one of the two EDOF IOL platforms, implanted bilaterally (the same platform in both eyes). Randomization uses permuted blocks and is stratified by toric versus non-toric IOL variant; patients with preoperative corneal astigmatism greater than 0.75 D receive the toric version of the assigned platform. Target refraction is emmetropia in the dominant eye and approximately -0.50 D in the non-dominant eye. Participants and outcome assessors are masked to lens allocation until the 6-month primary endpoint assessment is complete; the operating surgeon cannot be masked.

The study compares monocular (eye-level) and binocular (patient-level) outcomes between the two platforms. The primary endpoint is the monocular distance-corrected defocus range at the 0.2 logMAR threshold, measured 6 months after surgery from a standardized defocus curve (4-meter ETDRS chart, defocus +1.0 D to -3.5 D in 0.5 D steps). Secondary assessments include visual acuity at multiple distances, the complete defocus curve, manifest refraction and astigmatic vector components, higher-order wavefront aberrations, rotational stability of the toric variants, patient-reported visual function and quality of vision (including halos, glare, and starbursts), spectacle independence, satisfaction, and surgical safety.

Assessments are performed preoperatively and at 1, 3, and 6 months postoperatively. The primary analysis compares the mean monocular defocus range between groups using one eye per patient (the first-operated eye), with sensitivity analyses using both eyes and appropriate adjustment for within-patient correlation. The study is regulated as a post-market clinical follow-up (PMCF) investigation under Article 74(1) of Regulation (EU) 2017/745; both lenses are CE-marked and used within their approved intended purpose.