Study suggests how MRI shows brain changes in patina after COVID virus
Researchers have found brain changes in people up to six months after they have recovered from COVID-19 using a specific type of MRI.
The study will be presented next week at the annual meeting of the Radiological Society of North America.
According to the US Centers for Disease Control and Prevention, about one in five adults will develop long-term effects from COVID-19. Long-term neurological symptoms associated with the COVID virus include difficulty thinking or concentrating, headache, sleep disturbances, dizziness, tingling sensation, changes in smell or taste, and depression or anxiety. However, studies have shown that COVID-19 may be associated with changes in the heart, lungs or other organs even in asymptomatic patients.
As more people contract and recover from COVID-19, research is beginning to emerge focusing on the lasting effects of the disease.
In this study, researchers used susceptibility-weighted imaging to analyze the effects of COVID-19 on the brain. Magnetic susceptibility indicates how much certain materials, such as blood, iron and calcium, become magnetized in an applied magnetic field. This ability helps detect and monitor many neurological conditions, including microbleeds, vascular malformations, brain tumors, and stroke.
“Group-level studies have not previously focused on changes in brain magnetic susceptibility during COVID-19, despite several case reports demonstrating such abnormalities,” said the study’s co-author. Sapna S. Mishra, a PhD candidate at the Indian Institute of Technology, Delhi. “Our study highlights this new aspect of the neurological effects of COVID-19 and reports significant abnormalities among COVID survivors.”
The researchers analyzed sensitivity-weighted imaging data from 46 patients who had recovered from COVID and 30 healthy controls. The imaging was done within six months of recovery. For a long time, the most commonly reported symptoms in COVID patients were fatigue, sleep disturbances, lack of attention and memory problems.
“Changes in the sensitivity values of brain regions may be indicative of local compositional changes,” Mishra said. “Sensitivity may reflect abnormal amounts of paramagnetic compounds, while lower sensitivity may be due to abnormalities such as calcification or a lack of iron-containing paramagnetic molecules.”
The MRI results showed that susceptibility values in the frontal lobe and brainstem were significantly higher in patients who had recovered from COVID-19 compared to healthy controls. The clusters obtained in the frontal lobe mainly show differences in the white matter.
“These brain regions are associated with fatigue, insomnia, anxiety, depression, headaches and cognitive problems,” Mishra said.
The left orbital inferior frontal lobes (a key region for language comprehension and production) and the right orbital inferior frontal lobes (associated with various cognitive functions, including attention, motor inhibition and imagery, and social cognitive processes) and adjacent white matter regions formed the frontal lobe clusters.
The researchers also found a significant difference in the right ventral meningeal region of the brainstem. This area is involved in many vital bodily functions, including coordinating with the endocrine system to release hormones, transmitting sensory and motor signals to the cerebral cortex, and regulating circadian rhythms (the sleep-wake cycle).
“This study points to serious long-term complications that the coronavirus can cause even months after recovery from infection,” Mishra said. “The current observations are from a small temporal window. However, longitudinal time points of a couple of years clarify whether there is a permanent change.”
Researchers are conducting a longitudinal study with the same group of patients to determine whether these brain abnormalities persist over a longer period of time.