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Volumetric Visual Fields at Different Distances in Presbyopic Patients Using Occupational (PC-133 and PC-200) and General-Purpose Progressive Addition Lenses
Sponsor: University of Seville
Summary
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.
Official title: Ensayo clínico, unicéntrico, Transversal, Randomizado, Cruzado, Doble Ciego Para Evaluar Las Diferencias de Los Campos volumétricos de visión en Pacientes présbitas, Entre 400 y 40 cm., de Tres Tipos de Lentes oftálmicas Neutras de Lejos y adición Progresiva de 2 D. Dos de visión Intermedia y Cerca OPL (PC-133 y PC-200), y Otra Generalista PAL de visión Lejos, Intermedia y Cerca (FIT-FRM).
Key Details
Gender
All
Age Range
52 Years - 67 Years
Study Type
INTERVENTIONAL
Enrollment
28
Start Date
2026-06-08
Completion Date
2027-06-30
Last Updated
2026-10-13
Healthy Volunteers
No
Conditions
Interventions
OPAL PC 133 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.
OPAL PC 200 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
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
Locations (1)
Pharmacy School, University of Seville
Seville, Andalusia, Spain