Accommodation Disorders (AD)

• ClinicalTrials.gov Identifier: NCT01329848
• Recruitment Status: Completed
• First Posted: April 6, 2011
• Results First Posted: January 5, 2015
• Last Update Posted: January 5, 2015
• Sponsor: Western University of Health Sciences
• Collaborator: Southern California College of Optometry at Marshall B. Ketchum University
• Information provided by (Responsible Party): Christopher Chase, Western University of Health Sciences

Study Description

Brief Summary:

This project will develop clinically useful, objective measurements of accommodative insufficiency and fatigue using continuous autorefraction recordings. The development of these procedures will help vision care professionals diagnose and treat accommodative anomalies.

Condition or disease
Accommodative Insufficiency; Ill-sustained Accommodation

Detailed Description:

This project studies accommodative function, the ability to focus while doing near work. Visual discomfort symptoms, such as headaches, sore eyes, and blurred vision are commonly associated with prolonged reading or other near work. Researchers have long suspected accommodative dysfunction was involved but most clinical studies have failed to establish a relationship between weak accommodation and symptoms or reading impairments. Recent research, however, has found that clinical measure overestimate accommodative function and encourage the use of objective, autorefraction methods to measure and study accommodative weakness. This project will accomplish three goals. First, using autorefraction objective reliable procedures will be developed for measuring accommodative lag, the difference between the target location and where the eye is focused. Second, experiments will measure in real-time the impact of accommodative lag on reading fluency and visual discomfort systems. Third, studies will explore the role of the slow adaptive component in accommodative weakness. This work will lead to better methods for diagnosing and treating accommodative disorders.

Study Design

• Study Type: Observational
• Actual Enrollment: 83 participants
• Observational Model: Cohort
• Time Perspective: Prospective
• Official Title: Using Accommodative Lag to Diagnose Accommodation Disorders
• Study Start Date: December 2010
• Actual Primary Completion Date: December 2012
• Actual Study Completion Date: August 2013

Groups and Cohorts

Group/Cohort
discomfort symptoms; level of discomfort symptoms while performing near work

Outcome Measures

Primary Outcome Measures :

1. Accommodation Lag 5D [ Time Frame: 3 week period ]
   Lag will be measured at different viewing distances and durations using autorefraction. Accommodation error refers to the difference between the distance where the target is located and where the eyes focus. Lag refers error that is under focussed; lead is error that is over focussed. This distance is measured in diopters, or 1/meter.

Secondary Outcome Measures :

1. Conlon Symptom Survey [ Time Frame: 3 weeks ]
   Measures visual discomfort symptoms while doing near work. 23 item survey using a 4-point rating scale (never, occasionally, often, almost always). Total raw score reported on a range from 0 to 69 with higher scores indicating more frequent symptoms.

Eligibility Criteria

• Ages Eligible for Study: 18 Years to 30 Years (Adult)
• Sexes Eligible for Study: All
• Accepts Healthy Volunteers: Yes
• Sampling Method: Non-Probability Sample

Study Population

Graduate students from Western University of Health Sciences

Criteria

Inclusion Criteria:

• older adolescent and young adult
• skilled readers who attend school
• are skilled readers
• have heavy reading demands

Exclusion Criteria:

• Age > 30.
• Abnormal vergence system.
• Dry-eye.
• Uncorrected visual defects or significant ocular pathology.
• Learning disability or low IQ
• Medical conditions that might cause uncomfortable visual symptoms (e.g., migraine headaches, epilepsy, head trauma); sensory defects (e.g., deafness), or neurological conditions (e.g., stuttering) that could impair reading development or oral reading fluency.
• Somatosensory amplification.
• Systemic illness or medication associated with accommodative dysfunction.

Contacts and Locations

Locations

United States, California

Western University of Health Sciences

Pomona, California, United States, 91766

Sponsors and Collaborators

Western University of Health Sciences

Southern California College of Optometry at Marshall B. Ketchum University

Investigators

• Principal Investigator: Chris Chase, PhD; Western University of Health Sciences

More Information

• Responsible Party: Christopher Chase, Professor of Optometry, Western University of Health Sciences
• ClinicalTrials.gov Identifier: NCT01329848
• Other Study ID Numbers: 1R15EY021021 ( U.S. NIH Grant/Contract )
• First Posted: April 6, 2011
• Results First Posted: January 5, 2015
• Last Update Posted: January 5, 2015
• Last Verified: December 2014

Keywords provided by Christopher Chase, Western University of Health Sciences:

Accommodation; Reading; Autorefraction