An interventional study of OPAL PC 133 assessment and OPAL PC 200 assessment in Presbyopia, sponsored by University of Seville. Recruiting at 1 site in Spain. Open to participants aged 52 Years to 67 Years. Per ClinicalTrials.gov, last updated 2026-10-15.
Sponsored by University of Seville · Not applicable, Interventional, and Treatment
This single-center, randomized, double-blind, crossover clinical trial aims to compare the volumetric visual fields provided by two occupational progressive addition lenses (OPLs) optimized for intermediate and near vision in presbyopic patients. The study evaluates Vimax PC 1.5 FWD 133 cm and Vimax PC 1.5 FWD 200 cm lenses and Vimax Fit FRM, all of them with plano distance power and a +2.00 D near addition, in order to determine differences in the extent of clear vision at multiple working distances.
Participants will undergo a comprehensive optometric examination including medical and ocular history, visual acuity assessment, accommodative amplitude measurement, autorefraction, interpupillary distance measurement, ocular motility evaluation, confrontation visual fields, Amsler grid testing, and binocular vision assessment. Visual field measurements will then be performed using both study lenses under standardized conditions. Subjects will be instructed to maintain a fixed head position while identifying optotypes located at distances of 4 m, 2 m, 1.33 m, 80 cm, 40 cm, and 25 cm. Both lenses will be tested in random order under masked conditions so that neither participants nor investigators know which lens design is being evaluated during each phase.
At least 23 presbyopic participants are expected to be enrolled. The study procedures are non-invasive and are anticipated to be completed in a single one-hour visit, although additional sessions may be scheduled if necessary. No significant risks are expected beyond possible transient visual fatigue associated with the duration of testing.
The primary objective is to determine which occupational progressive lens design provides a greater spatial volume of clear vision and wider horizontal and vertical visual fields at different intermediate and near distances. The findings may contribute to improving personalized recommendations of occupational lenses according to patients' visual demands and working distances.
330 studies on the registry are indexed under Presbyopia; 35 are open to participants now.
This study's planned enrollment of 28 is below the median of 60 across 271 interventional studies indexed under Presbyopia.
Browse Presbyopia studies →University of Seville is the lead sponsor of 129 studies on the registry; 38 are open to participants now.
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Spherical ametropia for distance vision ≤ ±4.00 D and astigmatic ametropia ≤ 1.00 D.
Exclusion Criteria:
Occupational progressive lenses designed to provide clear vision from 133 cm to 40 cm, with a wider visual field optimized for monitor-based environments with a depth of field between 60 and 80 cm. These lenses, designated L1, were custom ordered with neutral distance power and a near addition of +2.00 D, a vertex distance of 13 mm, pantoscopic tilt of 8°, wrap angle of 6°, working distance of 40 cm, inset of 2.5 mm in both eyes, and NPD of 31 mm in each eye
Device: OPAL PC 133 assessment
Occupational progressive lenses designed to provide clear vision from 200 cm to 40 cm, with a wider visual field optimized for monitor-based environments with a depth of field between 60 and 80 cm. These lenses, designated L1, were custom ordered with neutral distance power and a near addition of +2.00 D, a vertex distance of 13 mm, pantoscopic tilt of 8°, wrap angle of 6°, working distance of 40 cm, inset of 2.5 mm in both eyes, and NPD of 31 mm in each eye
Device: OPAL PC 200 assessment
Progressive additional lenses custom ordered with neutral distance power and a near addition of +2.00 D, vertex dis-tance of 13 mm, pantoscopic tilt of 8°, wrap angle of 6°, working distance of 40 cm, inset of 2.5 mm in both eyes, and NPD of 31 mm in both eyes.
Device: PAL assessment
Fitting and positioning of the spectacles : participants were instructed to move only their eyes and to verbally identify the letters indicated by the optometrist. Measurement of clear vision limits: the horizontal and vertical boundaries of clear vision were recorded on a scaled results sheet, as defined by the participant using the optotype, at distances of 400, 200, 133, 80, 40, and 25 cm, in that order.
Fitting and positioning of the spectacles : participants were instructed to move only their eyes and to verbally identify the letters indicated by the optometrist. Measurement of clear vision limits: the horizontal and vertical boundaries of clear vision were recorded on a scaled results sheet, as defined by the participant using the optotype, at distances of 400, 200, 133, 80, 40, and 25 cm, in that order
Fitting and positioning of the spectacles : participants were instructed to move only their eyes and to verbally identify the letters indicated by the optometrist. Measurement of clear vision limits: the horizontal and vertical boundaries of clear vision were recorded on a scaled results sheet, as defined by the participant using the optotype, at distances of 400, 200, 133, 80, 40, and 25 cm, in that order
Visual field volume
It will consist of the volume defined by two parallel surfaces bounded by the visual fields perceived with clear horizontal and vertical vision by the patient between the distances of 4 m and 25 cm while wearing each pair of spectacles. The volume will be calculated using the Heronian formula for the volume of a quadrangular pyramidal frustum.
Time frame: Immediately after the adjustment of the frame where the lenses were placed, an average of 30 minutes per patient.
Visual fields surface
Calculation of the visual field surface areas defined by the patient with each lens type at distances of 4 m, 2 m, 1.33 m, 80 cm, 40 cm, and 25 cm. For this purpose, the areas corresponding to the visual field regions of the lens located between the fitting cross and the intermediate and near viewing zones were summed in a 1:2 proportion, respectively, for each measured distance.
Time frame: Immediately after the adjustment of the frame where the lenses were placed, an average of 30 minutes per patient
Documents are hosted by the registry — open the source record to download them.
Plan to share: No
Ran from Jun 2026 to primary completion in Jun 2026, 0 months.
Of 38 non-industry interventional studies with no phase under Presbyopia, half reached primary completion within 12 months of starting (the median), counting those still running; a quarter within 6 and three quarters within 23. This study's 0 months is below that.
Counting every sponsor, half of 125 studies reached it within 10 months; a quarter within 3 and three quarters within 22.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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