Test-Retest Variability of Quick Contrast Sensitivity Function Testing

Nova Southeastern University100 enrolled

Overview

The contrast sensitivity function (CSF) provides a comprehensive characterization of spatial vision and predicts functional vision better than visual acuity, but long testing times prevent its psychophysical assessment in clinical applications. Dr. Luis Lesmes et al. (2010) developed the qCSF method to obtain precise CSF measurements in only 30-50 trials using a computerized software program that presents letters on a large monitor that are identified by a patient similar to typical visual acuity testing with an eye chart. The quick CSF method is a Bayesian adaptive method that estimates the full shape of the CSF, and the test duration is only about 3-6 minutes. Some preliminary testing has been performed at other sites with this test in patients with vision loss due to amblyopia and glaucoma, but data from individuals without eye disease who have normal visual acuity has not been systematically collected with the latest version of this test procedure across a wide range of ages. In addition, we aim to gain a better understanding of the typical test-retest variability that is obtained between-sessions that are about a week apart from individuals with good ocular health and visual acuity.

Study Type

OBSERVATIONAL

Enrollment

100

Conditions

Healthy

Interventions

quick Contrast Sensitivity Function test

Eligibility

Sex: ALLMin age: 20 YearsMax age: 89 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Ages 20-89 * Normal distance visual acuity in each of both eyes (20/20) * Absence of ocular disease * Able and willing to complete contrast sensitivity testing * Provide informed consent Exclusion Criteria: * Any ocular disease * Refractive errors \>6D * Inability to understand study or communicate responses (cognitive impairment) * Unable to understand, read and speak English fluently

Outcomes

Primary Outcomes

95% coefficient of repeatability across subjects

We will evaluate various contrast sensitivity metrics that are generated by the computer program: (i) AULCSF or area under the curve for the log contrast sensitivity function (CSF), (ii) CSF acuity or the cutoff-frequency at which sensitivity=2.0 is calculated, and (iii) contrast sensitivity at various spatial frequencies (i.e. 1.5, 3, 6, 12, 18.5 cycles per degree), obtained with testing performed binocularly, with the better eye monocularly, and with the better eye using a NoIR 4% transmission filter. Within subject, the data will be analyzed as differences between the two values obtained at the two sessions, which can then be used to determine a 95% coefficient of repeatability across subjects.

Time frame: test-retest at 2 visits about a week apart