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

Not Applicable

Completed

Conditions: Presbyopia

Interventions: Device: Standard, non-free-form, non-customized PAL spectacles
Device: Individually customized free-form surfaced PAL spectacles

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

Arm && Interventions

Group	Intervention	Description
Randomized Order of Interventions 2	Individually customized free-form surfaced PAL spectacles	Randomized to first wear individually customized free-form surfaced PAL spectacles, then second, crossover to wear standard, non-free-form, non-customized PAL spectacles
Randomized Order of Interventions 1	Standard, non-free-form, non-customized PAL spectacles	Randomized to first wear standard, non-free-form, non-customized PAL spectacles, then second, crossover to wear individually customized free-form surfaced PAL spectacles
Randomized Order of Interventions 1	Individually customized free-form surfaced PAL spectacles	Randomized to first wear standard, non-free-form, non-customized PAL spectacles, then second, crossover to wear individually customized free-form surfaced PAL spectacles
Randomized Order of Interventions 2	Standard, non-free-form, non-customized PAL spectacles	Randomized to first wear individually customized free-form surfaced PAL spectacles, then second, crossover to wear standard, non-free-form, non-customized PAL spectacles

Primary Outcome Measures

Name	Time	Method
Visual Acuity, Low Contrast, Distance Chart	Post-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 Battery	At 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 Distance	Post-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 Chart	Post-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 Chart	Post-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 Chart	Post-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 Chart	Post-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 Chart	Post-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