Clinical trial NCT02679313: Effect of Lens Presentation on the Clinical Oculomotor Assessment at Near
Official title: Effect of Lens Presentation on the Clinical Oculomotor Assessment at Near
Study type: INTERVENTIONAL
Overall status: WITHDRAWN
Phase: NA
Conditions: Vision Disorders
Lead sponsor: State University of New York College of Optometry
Sponsor class: OTHER
First posted: 2016-02-10
Enrollment: 0
Sex: ALL
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: DIAGNOSTIC

Brief summary: This study will compare near clinical oculomotor parameters (heterophoria, vergence ranges, AC/A and accommodative findings) measured when lenses and/or prisms are introduced using three different instruments namely: (i) a standard manual phoropter, (ii) an electronic phoropter and (iii) a wearable adaptive refractor (VisionFit).

Detailed description: Previous studies have demonstrated differences in a number of near oculomotor parameters \[e.g., heterophoria, accommodative convergence to accommodation (AC/A) ratio\] when measured in a manual phoropter versus a trial frame. These differences may be due to variations in proximal vergence, differences in head and eye position and restriction of the peripheral visual field. Further, a number of standard clinical oculomotor procedures require the use of Risley rotary prisms. While prism is typically introduced in a smooth, ramp-like fashion with manual phoropters, step changes in prism are created with electronic phoropters. The precise effect of these variations on clinical measurements is unclear. Accordingly, after a routine refractive examination, a standard clinical near assessment (comprising near heterophoria, AC/A ratio, horizontal vergence ranges, amplitude of accommodation and negative and positive relative accommodation) will be carried out on the same individuals through: (i) a standard manual phoropter (American Optical model 11625), (ii) an electronic phoropter (Topcon CV-5000) and (iii) a wearable adaptive refractor (VisionFit). The latter resembles a trial frame mounted on a helmet carrier (similar to a binocular indirect ophthalmoscope headset) but includes adaptive lenses that can be changed electronically.

Eligibility criteria: Inclusion Criteria:

* Corrected visual acuity of at least 20/20 (logMAR = 0.0) or better in each eye

Exclusion Criteria:

* Strabismus, amblyopia, manifest ocular disease.

Primary outcomes:
measure: Near horizontal heterophoria
timeFrame: approximately 15 minutes
measure: Accommodative convergence to accommodation (AC/A) ratio
timeFrame: approximately 15 minutes
measure: Horizontal near vergence ranges
timeFrame: approximately 15 minutes
measure: Minus lens amplitude of accommodation
timeFrame: approximately 15 minutes
Secondary outcomes:
measure: Negative and Positive Relative Accommodation (NRA and PRA)
timeFrame: approximately 15 minutes
Other outcomes:
Locations:
city: New York
country: United States
facility: SUNY College of Optometry
state: New York
Study officials:
affiliation: State University of New York College of Optometry
name: Mark Rosenfield, MCOptom, PhD
role: PRINCIPAL_INVESTIGATOR
References: