Optical tests may serve as biomarkers in mTBI
BOSTON – Researchers found that pupillary light reflex and near point of convergence may serve as objective biomarkers for mild traumatic brain injury, according to a poster presented here at Optometry’s Meeting.
Lead author Jose E. Capo-Aponte, OD, during a session featuring the top posters of the meeting, explained that the study comprised 100 acute non-blast mild traumatic brain injury (mTBI) and 100 age-matched controls between 19 and 44 years old.
Researchers utilized a handheld monocular infrared pupilometer (NeuroOptics, PLR-200) and recorded the following measurements: maximum pupil diameter, minimum diameter, percent of constriction, constriction latency, average constriction velocity, maximum constriction velocity, average dilation velocity and 75% re-dilation recovery time.
The King-Devick (KD) Test was used to determine saccadic eye movement.
Average dilation velocity and 75% re-dilation recovery time were significantly reduced in mTBI subjects, according to researchers. Additionally, near point of convergence (NPC) value, KD Test score and Convergence Insufficiency Symptoms Survey (CISS) score were significantly higher in mTBI patients.
He added that the symptoms of mTBI can mirror post-traumatic stress disorder.
The results strongly suggest that pupillary light reflex and NPC can serve as objective biomarkers for mTBI. CISS and KD Test might be useful for identifying acute mTBI, even considering the subjective component to these tests, the researchers reported. Also the tests are handheld, easy to use, quick, deployable and easily administered by non-providers.
According to Capo-Aponte, 82% of Army TBI cases are considered mTBI cases.
“It is important to return to duty, but it’s also important to find biomarkers for TBI to identify those with mTBI so people can return back to duty, but do so appropriately and by decreasing a soldier’s chance of having another TBI,” he concluded – by Abigail Sutton
Capo-Aponte JE, et al. Validation study of visual objectives biomarkers for acute mild traumatic brain injury. Presented at: Optometry’s Meeting; June 29 – July 2, 2016; Boston.
Disclosure: Capo-Aponte is active duty Army, and the study was supported by the Department of Defense.