Back to Search Start Over

Effect of luminance on the visually-evoked potential in visually-normal individuals and in mTBI/concussion.

Authors :
Fimreite, Vanessa
Ciuffreda, Kenneth J.
Yadav, Naveen K.
Source :
Brain Injury; Sep2015, Vol. 29 Issue 10, p1199-1210, 12p
Publication Year :
2015

Abstract

Purpose: To assess quantitatively the effect of luminance on VEP amplitude and latency in visually-normals (VN) and patients with mild traumatic brain injury (mTBI). Methods: VN individuals (n = 20) and those with mTBI (n = 19) participated. Those with mTBI were assessed 1–10 years post-injury (mean = 4.97 years), with the exception of one subject. Pattern VEP testing was employed using the DIOPSYS™ NOVA–TR system, with a 74 cd m−2baseline luminance. Luminance levels were reduced with five different neutral density (ND) filters (0.5, 1.0, 1.5, 2.0 and 2.5) and compared to the baseline response. All testing was performed under binocular-viewing conditions with full refractive correction in place. Results: In both groups, mean VEP amplitude reduced with decrease in luminance (p < 0.05). At each luminance level, the mean VEP amplitude was significantly lower in mTBI than in the VN population (p < 0.05). In both groups, the mean VEP latency increased progressively with reduction in luminance (p < 0.05), with it being significantly higher in mTBI than in the VN population (p < 0.05). Conclusions: High luminance levels produced an optimal VEP response in both populations. VEP amplitude was robust, whereas latency progressively increased in both groups as luminance decreased. The latency increase with decreased luminance was significantly larger in those with mTBI, thus suggesting that latency can be used to differentiate reliably between VN individuals and those with mTBI. [ABSTRACT FROM PUBLISHER]

Details

Language :
English
ISSN :
02699052
Volume :
29
Issue :
10
Database :
Complementary Index
Journal :
Brain Injury
Publication Type :
Academic Journal
Accession number :
108975754
Full Text :
https://doi.org/10.3109/02699052.2015.1035329