In contrast, vHIT and VEMP are both so new that researchers are still working to establish normal vs. abnormal, and to correlate vHIT and VEMP results with clinical conditions. Because the new tests assess the vestibular system in ways that were previously impossible, however, healthcare providers are beginning to incorporate them into clinical practice.
Video Head Impulse Testing (vHIT)
“In a lot of ways, video head impulse testing has revolutionized our ability to test the function of the canals in a rigorous, quantitative way,” said Yuri Agrawal, MD, assistant professor of otolaryngology-head and neck surgery at Johns Hopkins University School of Medicine in Baltimore.
The FDA approved vHIT in 2013. The test utilizes a pair of video-equipped goggles to record eye movements in response to head movement. The testing equipment records and compares both the direction and velocity of head movement and the direction and velocity of eye movement. Well tolerated by most patients, vHIT measures the function of all six semicircular canals in each ear in about 10 minutes. (Caloric testing, in contrast, takes approximately 30 minutes and cannot be tolerated by some patients.)