New Delhi, Nov 22
Sapna S. Mishra, a PhD candidate at the Indian Institute of Technology in Delhi, and a team of researchers have used a special type of MRI to uncover brain changes in patients up to six months after they recovered from Covid-19.

MRI results showed that patients who recovered from Covid-19 had significantly higher susceptibility values in the frontal lobe and brain stem compared to healthy controls.

"These brain regions are linked with fatigue, insomnia, anxiety, depression, headaches and cognitive problems," said study co-author Mishra.

The researchers also found a significant difference in the right "ventral diencephalon region" of the brain stem.

This region is associated with many crucial bodily functions, including coordinating with the endocrine system to release hormones, relaying 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 may be caused by the coronavirus, even months after recovery from the infection," she noted.

About one in five adults will develop long-term effects from Covid-19, according to the US Centers for Disease Control and Prevention (CDC).

Neurological symptoms associated with long Covid include difficulty thinking or concentrating, headache, sleep problems, lightheadedness, pins-and-needles sensation, change in smell or taste, and depression or anxiety.

However, studies have found that Covid-19 may be associated with changes to the heart, lungs or other organs even in asymptomatic patients.

"Group-level studies have not previously focused on Covid-19 changes in magnetic susceptibility of the brain despite several case reports signaling such abnormalities," said Mishra.

"Our study highlights this new aspect of the neurological effects of Covid-19 and reports significant abnormalities in Covid survivors," she added.

The story was scheduled to be presented next week at the annual meeting of the Radiological Society of North America (RSNA) in Chicago.

For this study, researchers used susceptibility-weighted imaging to analyse the effects that Covid-19 has on the brain.

The researchers analysed the susceptibility-weighted imaging data of 46 Covid-recovered patients and 30 healthy controls.

Among patients with long Covid, the most commonly reported symptoms were fatigue, trouble sleeping, lack of attention and memory issues.

"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," she noted.

IIT-Delhi researcher reveals significant brain abnormalities in long Covid patients