Citation

Yaramothu C, Greenspan LD, Scheiman M, Alvarez TL. J. Neurotrauma 2019; 36(14): 2200-2212.

Affiliation

New Jersey Institute of Technology Newark College of Engineering, 122389, Biomedical Engineering , 323 Martin Luther King Blvd , Newark , Newark, New Jersey, United States , 07102-1982 ; tara.l.alvarez@njit.edu.

Copyright

(Copyright © 2019, Mary Ann Liebert Publishers)

DOI

10.1089/neu.2018.6075

PMID

30829134

Abstract

The Vergence Endurance Test (VET), a quantitative and objective eye movement assessment, was utilized to differentiate control from concussed subjects. Nine symptomatic concussed (2 Male 30.8±11 years) and nine asymptomatic control (6 Male 25.1±1.4 years) subjects participated in the VET. Symmetrical disparity vergence step targets were presented with and without visual distractors. A masked data analyst measured vergence latency, peak velocity, response amplitude, settling time, and the percentage of trials which contained blinks. A Binocular Precision Index (BPI) and a Binocular Accuracy Index (BAI) were calculated to quantify the changes that occur in the vergence parameters over the duration of the VET. Convergence and divergence peak velocity, divergence response amplitude, the percentage of trials that contained blinks during the transient portion of the response, and the BAI were significantly (p<0.05) different between the concussed and the control subjects. For these parameters, the BAI and divergence response amplitude yielded the greatest accuracy, 78%, in their ability to discriminate between the groups. The VET objectively measures the change in vergence performance over time and shows promise as a method to diagnose a concussion. Future studies will determine whether the VET can be used to assess the extent of natural recovery and the effectiveness of therapeutic interventions.

Language: en

Keywords

ADULT BRAIN INJURY; BIOMARKERS; Behavior; Other