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Clinical Assessment of a Customized Free-form Progressive Addition Lens Spectacle

Not Applicable
Completed
Conditions
Presbyopia
Registration Number
NCT01234207
Lead Sponsor
University of California, Berkeley
Brief Summary

The purpose of this study was to compare objective clinical measures of visual performance and subjective measures of satisfaction and preference between standard progressive addition lens (PAL) spectacles and a new type of free-form surfaced, optically customized PAL spectacle.

Detailed Description

In a double-masked crossover trial, 95 experienced wearers wore customized free-form PAL spectacles (Test) and standard non-free-form PAL spectacles (Control) for one week each. All subjects wore both Test and Control spectacles, and the pair to be worn first was randomly assigned. At dispensing and after 1 week of wear, subjects were tested for distance and near visual acuity (VA) under both high and low contrast; in addition, 30 degree off-axis VA was measured using a novel apparatus, as was the horizontal extent of undistorted vision at reading distance. Subjects also completed a set of questionnaires detailing their satisfaction levels, adaptation times, and preferences for Test or Control spectacles for different visual tasks.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
95
Inclusion Criteria
  • Presbyope
  • Experienced PAL spectacle wearer
  • Correctable to at least 20/25 in both eyes
  • Able and willing to use Test and Control spectacles for 1 week each as primary form of presbyopia correction
  • Able and willing to complete all laboratory measurements and questionnaire batteries
Exclusion Criteria
  • Purchasing free-form PAL spectacles from the UC Berkeley Eyewear Center
  • Having eye conditions or diseases that could potentially cause a decrease in visual acuity over the course of participation in the study
  • Having eye conditions or diseases that could potentially interfere with ability to use Test and Control spectacles as primary form of presbyopia correction

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Primary Outcome Measures
NameTimeMethod
Visual Acuity, Low Contrast, Distance ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Standard assessment of low contrast visual acuity at distance, as in normal clinical practice, using Baily-Lovey charts and the M\&S Technologies Smart System II visual acuity projection system.

Questionnaire BatteryAt study exit, after both Test and Control spectacles had been worn for 1 week each

Forced-choice Likert scale preference questionnaire

Horizontal Extent of Undistorted Vision at Reading DistancePost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Novel apparatus designed to immobilize head and allow subject to indicate point of peripheral optical distortion on a modified Amsler-type grid

Visual Acuity, High Contrast, Distance ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Standard assessment of high contrast visual acuity at distance, as in normal clinical practice, using Baily-Lovey charts and the M\&S Technologies Smart System II visual acuity projection system.

Visual Acuity, High Contrast, Near ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Standard assessment of high contrast visual acuity at near, as in normal clinical practice, using Baily-Lovey charts and the M\&S Technologies Smart System II visual acuity projection system.

Visual Acuity, Low Contrast, Near ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Standard assessment of low contrast visual acuity at near, as in normal clinical practice, using Baily-Lovey charts and the M\&S Technologies Smart System II visual acuity projection system.

30-degree Off-axis Distance Visual Acuity, Low Contrast ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Measured with subject immobilized in specially designed apparatus, keeping head pointed straight forward and moving only the eyes to left or right to view the off-axis chart

30-degree Off-axis Distance Visual Acuity, High Contrast ChartPost-1 week of wear of Test Spectacles and post-1 week of wear of Control Spectacles

Measured with subject immobilized in specially designed apparatus, keeping head pointed straight forward and moving only the eyes to left or right to view the off-axis chart

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Clinical Research Center, School of Optometry, University of California, Berkeley

🇺🇸

Berkeley, California, United States

Clinical Research Center, School of Optometry, University of California, Berkeley
🇺🇸Berkeley, California, United States

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