How eye movements help doctors see long COVID neurological effects
Courtesy of Allegheny Health Network
Neurologist Dr. Kevin Kelly, who operates the AHN Post Covid Neurology Outpatient Clinic, shows the machine that helps researchers explore the use of novel eye tracking technology to assess long lasting COVID-related neurological problems.
Courtesy of Allegheny Health Network
Neurologist Dr. Kevin Kelly, who operates the AHN Post Covid Neurology Outpatient Clinic, helps a patient put on goggles to assist in their study of some long-lasting COVID symptoms.
Many people who contracted COVID-19 experienced only mild symptoms or none at all, and later tested negative before breathing a sigh of relief.
For a growing number of people, though, the real problems emerge a few days, weeks or months later in the form of ringing in the ears, numbness in extremities, blurred vision, headaches, loss of taste or smell, and dizziness. Doctors call this Neurological Long-COVID, and the number of cases is climbing.
According to the National Institutes of Health, there is a need for rigorous studies on these neurological symptoms and the long-lasting effects. Some of that research is already underway in Pittsburgh where Allegheny Health Network (AHN) neurologists recognized the need for a specialized clinic for post-COVID patients who were left dealing with a wide variety of neurological effects. One of the ways researchers are studying these issues is by tracking patients’ eye movements.
Neurologist Dr. Kevin Kelly, who operates the AHN Post Covid Neurology Outpatient Clinic, is now concluding a pilot study on the use of oculomotor goggles that analyze eye movements.
“Cognitive dysfunction, or brain fog, is the most common complaint in patients with long-haul COVID-19,” Kelly said, “but the list is long and continues to grow.”
The research, funded by Neurolign Technologies, is exploring the efficacy of Neurolign’s computerized eye movement tracking goggles for helping to analyze a patient’s oculomotor, vestibular, reaction time and cognitive functions.
Examples of cognitive dysfunction experienced by COVID patients span the spectrum from short-term memory impairment and attention deficit to profound confusion and inability to perform activities of daily living.
“Studies of COVID-19’s impact on the brain are critically important because the more we learn about the manifestations, the better equipped we are to help our current and future long hauler patients,” Kelly said. “That’s why we are excited to be exploring the potential of Neurolign’s technology. The eyes are a window into the workings of the brain, and eye movements are closely linked to cognitive processes.”
Kelly said the pilot study has gone well with 20 subjects between 18-45 years of age who had long Covid symptoms. Doctors evaluated each person three times over six months with eye-tracking technology and other techniques.
“What we have found striking in many of the subjects is how well their symptoms correlate with the eye-tracking results,” said Kelly, who added some subjects have little change in their symptoms and eye-tracking abnormalities over the six-month period, whereas some subjects’ symptoms improve steadily along with their eye-tracking results. “I believe these results can translate to focusing on different forms of therapy.”
Looking for answers
Why do some patients recover from COVID quickly while others suffer long-term effects?
Kelly said there’s no easy answer.
“I believe that genetic factors must play a role in the variability of clinical courses,” he said. “COVID clearly can affect the brain due to the body’s inflammatory responses and possibly due to the persistence of the virus in the body and the presence of microclots in the brain’s blood vessels.”
A recent study published in the Annals of Clinical and Translational Neurology by Northwestern University found 85% of long-haul patients, or those with symptoms lingering nine months or longer following their illness, reported four or more neurologic symptoms.
For many patients, symptoms do ease or even resolve over time. For those needing treatment, the eye-tracking technology can assess abnormal eye movement responses to different stimuli by comparing them with 300 normal subjects.
“Through our understanding of the different brain circuits that mediate eye movements, we can better understand how different parts of the brain may be affected in a given patient,” Kelly said.
Kelly said the hope is this research will be able to help those affected by long-term COVID and enhance clinical practice by providing a better assessment tool to screen for these neurological impacts and guide treatment.