Effect of binasal occlusion (BNO) and base-in prisms on the visual-evoked potential (VEP) in mild traumatic brain injury (mTBI). (November 2014)

• Record Type: Journal Article
• Authors: Yadav, Naveen K.; Ciuffreda, Kenneth J.
• Is Part Of: Brain injury. Volume 28:Number 12(2014)
• Page Start: 1568
• Page End: 1580
• Publication Date: 2014-11
• Subjects: Brain damage -- Periodicals; Brain -- Wounds and injuries -- Periodicals; Brain Injuries -- Periodicals; 617.481
• DOI: 10.3109/02699052.2014.939718
• Languages: English
• ISSNs: 0269-9052

Abstract

<abstract> <title>Abstract</title> <p> <italic>Purpose</italic>: To assess quantitatively the effect and relative contribution of binasal occlusion (BNO) and base-in prisms (BI) on visually-evoked potential (VEP) responsivity in persons with mild traumatic brain injury (mTBI) and the symptom of visual motion sensitivity (VMS), as well as in visually-normal (VN) individuals.</p> <p> <italic>Research design and methods</italic>: Subjects were comprised of 20 VN adults and 15 adults with mTBI and VMS. There were four test conditions: (1) conventional pattern VEP, which served as the baseline comparison condition; (2) VEP with BNO alone; (3) VEP with 2 pd BI prisms before each eye; and (4) VEP with the above BNO and BI prism combination.</p> <p> <italic>Results</italic>: In mTBI, the mean VEP amplitude <italic>increased</italic> significantly in <italic>nearly all</italic> subjects (∼90%) with BNO alone. In contrast, in VN, it <italic>decreased</italic> significantly with BNO alone in <italic>all</italic> subjects (100%), as compared to the other test conditions. These objective findings were consistent with improvements in visual impressions and sensorimotor tasks in the group with mTBI. Latency remained within normal limits under all test conditions in both groups.</p> <p> <italic>Conclusions</italic>: Only the BNO condition demonstrated significant, but opposite and consistent, directional effects on the VEP amplitude in both groups. The BNO-VEP test condition may be used clinically for the objectively-based, differential diagnosis of persons suspected of having mTBI and VMS from the VNs.</p> </abstract>