Summary: Researchers report a blink reflexometer may help doctors to diagnose neurological problems, from TBI to Parkinson’s disease, in patients.
Source: Medical University of South Carolina.
The blink reflex has been shown to be sensitive to a number of neurological insults, including traumatic brain injury, Parkinson’s disease and Huntington’s disease, suggesting that it could be a useful tool for neurological assessment. Although electromyography (EMG)-derived time metrics were used to analyze the blink reflex as early as the 1950s, quantitative assessment of the blink response was never adopted widely in clinical practice, in part because existing technology was somewhat cumbersome and uncomfortable. Moreover, EMG is a highly sensitive technology requiring strict ambient parameters and was not easily performed outside the health care setting, limiting the applications of the blink reflex as a diagnostic indicator of neurological health. Advances in video and computer technology — including improved digital image capture, higher frame speeds and higher processing speeds — have now put portable, noninvasive, quantitative assessment of the blink within reach.
The Blink Reflexometer, a portable device developed by the Zucker Institute for Applied Neurosciences at the Medical University of South Carolina that has since been licensed to BLINKtbi (Charleston, SC), uses high-speed video to capture and quantitatively analyze a series of blinks that it stimulates with puffs of air. The device analyzes the recorded blinks based on data acquired from decades of blink reflex research to determine if the patient has experienced neurological insult.
In a validation study in ten healthy college students, the results of which were reported in an article published online December 12, 2017 by the IEEE Journal of Translational Engineering in Health and Medicine, a team of investigators at the Medical University of South Carolina and The Citadel obtained blink measurements for ten healthy college students using the Blink Reflexometer and compared them to published measurements obtained with EMG. Three parameters were measured: latency (time between stimulus to first eyelid movement), differential latency (difference in start time between eyelids) and duration (time from start of eyelid movement to eyelid open). Latency and duration measurements obtained with the Blink Reflexometer were in line with published results; only differential latency fell outside of published ranges. These findings suggest that the Blink Reflexometer can provide quantitative measurements of the blink that are on par with those obtained via EMG.
“We are excited to be able to take something that had been qualitative and make it quantitative and objective,” says lead author Nancey Trevanian Tsai, M.D. “We talk about metrics all the time in medicine but when you are actually able to provide quantitative, objective data, it’s a game changer. It’s analogous to the difference between saying someone is feverish to measuring the patient’s temperature, an objective measurement, with a thermometer.”
This study was based on a small number of young, healthy patients, so larger studies in participants that better represent the general populace will be required. More studies will also be required to verify the usefulness of the blink reflex and of this novel device for neurological assessment in each area of clinical need. Although the Blink Reflexometer can measure changes in the blink reflex, it does not provide information on the underlying causes of those changes.
If the findings of those studies are promising, the device could make it possible to include the blink reflex as a metric or vital sign in medical examination. Because it is portable, it could be taken into the field for on-site neurological assessments. Potential uses are field-side assessment of athletes for concussion or field sobriety tests for marijuana intoxication.
The Blink Relexometer is patent pending and available for investigational use only. The Medical University of South Carolina, the Zucker Institute for Applied Neurosciences and authors Tsai, Semler and Kothera have financial interest in the technology.
Funding: Funding provided by Zucker Institute for Applied Neurosciences.
Source: Heather Woolwine – Medical University of South Carolina
Publisher: Organized by NeuroscienceNews.com.
Image Source: NeuroscienceNews.com image is credited to Tsai NT, et al, IEEE Journal of Translational Engineering in Health and Medicine.
Original Research: Full open access research for “Development of a Non-Invasive Blink Reflexometer” by Nancey Trevanian Tsai; Jesse S. Goodwin; Mark E. Semler; Ronald T. Kothera; Mark Van Horn; Bethany J. Wolf; and Dena P. Garner in IEEE Journal of Translational Engineering in Health and Medicine. Published online December 12 2017 doi:10.1109/JTEHM.2017.2782669
Development of a Non-Invasive Blink Reflexometer
Qualitative assessments of the blink reflex are used clinically to assess neurological status in critical care, operating room, and rehabilitative settings. Despite decades of literature supporting the use of quantitative measurements of the blink reflex in the evaluation of multiple neurological disorders, clinical adoption has failed. Thus, there remains an unmet clinical need for an objective, portable, non-invasive metric of neurological health that can be used in a variety of settings. We have developed a high-speed videography-based device to trigger, record, and analyze a blink reflex. A pilot study was performed to compare the device’s measurements to the published literature of electromyographic measurements, currently the gold standard. The study results indicate that the device is a viable tool to obtain fast, objective, and quantitative metrics of a blink reflex, and has promise as a non-invasive diagnostic assessment of neurological health.
“Development of a Non-Invasive Blink Reflexometer” by Nancey Trevanian Tsai; Jesse S. Goodwin; Mark E. Semler; Ronald T. Kothera; Mark Van Horn; Bethany J. Wolf; and Dena P. Garner in IEEE Journal of Translational Engineering in Health and Medicine. Published online December 12 2017 doi:10.1109/JTEHM.2017.2782669