Using a specific type of MRI, researchers observed brain changes in people up to six months after they recovered from COVID-19. The work will be presented at the annual conference of the Radiological Society of North America next week. According to the Centers for Disease Control and Prevention, around one in every five individuals will experience long-term consequences from COVID-19. Long-term COVID causes neurological symptoms such as trouble thinking or focusing, headache, sleep issues, lightheadedness, pins-and-needles feeling, change in smell or taste, and depression or anxiety. COVID-19, on the other hand, has been linked to abnormalities in the heart, lungs, and other organs in asymptomatic people, according to research.
As more people become infected with and recover from COVID-19, research concentrating on the disease’s long-term implications has begun to surface. The researchers employed susceptibility-weighted imaging to examine the effects of COVID-19 on the brain in this investigation. Magnetic susceptibility is the degree to which particular materials, such as blood, iron, and calcium, will become magnetised in the presence of a magnetic field. This skill facilitates in the detection and monitoring of a variety of neurologic disorders such as microbleeds, vascular malformations, brain tumours, and stroke.
“Group-level studies have not previously focused on COVID-19 changes in magnetic susceptibility of the brain despite several case reports signalling such abnormalities,” said study co-author Sapna S. Mishra, a PhD candidate at the Indian Institute of Technology in Delhi. “Our study highlights this new aspect of the neurological effects of COVID-19 and reports significant abnormalities in COVID survivors.”
The susceptibility-weighted MRI data of 46 COVID-recovered patients and 30 healthy controls were examined by the researchers. Imaging was performed six months after recovery. The most often reported symptoms among individuals with extended COVID were weariness, difficulty sleeping, loss of focus, and memory problems.
“Changes in susceptibility values of brain regions may be indicative of local compositional changes,” Mishra said. “Susceptibilities may reflect the presence of abnormal quantities of paramagnetic compounds, whereas lower susceptibility could be caused by abnormalities like calcification or lack of paramagnetic molecules containing iron.”
When MRI data were compared to healthy controls, patients who recovered from COVID-19 had considerably greater susceptibility levels in the frontal lobe and brain stem. The frontal lobe clusters found mostly exhibit variations in white matter.
“These brain regions are linked with fatigue, insomnia, anxiety, depression, headaches and cognitive problems,” Mishra said.
The frontal lobe clusters were made up of portions of the left orbital-inferior frontal gyrus (a key region for language comprehension and production) and right orbital-inferior frontal gyrus (associated with various cognitive functions such as attention, motor inhibition, and imagery, as well as social cognitive processes) and the adjacent white matter areas.
The researchers also discovered a substantial difference in the brain stem’s right ventral diencephalon area. This area is involved in several important biological activities, such as coordinating hormone release with the endocrine system, sending sensory and motor impulses to the cerebral cortex, and regulating circadian cycles (the sleep-wake cycle).
“This study points to serious long-term complications that may be caused by the coronavirus, even months after recovery from the infection,” Mishra said. “The present findings are from the small temporal window. However, the longitudinal time points across a couple of years will elucidate if there exists any permanent change.”
The researchers are now doing a long-term investigation on the same patient group to see if these brain anomalies remain over time.