Coronavirus disease 2019 (COVID-19) is a contagious respiratory and vascular disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
In the early months of the COVID-19 pandemic, doctors struggled to keep patients breathing and focused mainly on treating damage to the lungs and circulatory system. But even then, evidence for neurological effects was accumulating.
A new study at Harvard-affiliated Massachusetts General Hospital (MGH) has shown early brain damage in COVID patients. This is one of the first spectroscopic imaging-based studies of neurological injury in COVID-19 patients.
Taking a gander at six patients utilizing a specialized magnetic resonance (MR) method, they found that COVID-19 patients with neurological symptoms show a portion of the same metabolic disturbances in mind as patients who have suffered oxygen deprivation (hypoxia) from other causes; however, there are also notable differences.
It is believed that the disease’s primary effect on the brain is through hypoxia, yet a couple of studies have archived the particular sorts of damage that distinguish COVID-19-related related injury. Several thousand patients with COVID-19 have been seen at the MGH since the outbreak began early this year, and this examination included discoveries from three of those patients.
The severity of neurological manifestations varies, going from one of the most notable — a temporary loss of smell — to more severe side effects, for example, dizziness, confusion, seizures, and stroke.
Eva-Maria Ratai, an investigator in the Department of Radiology and senior author of the study, said, “We were interested in characterizing the biological underpinnings of some of these symptoms. Moving forward, we are also interested in understanding the long-term lingering effects of COVID-19, including headaches, fatigue, and cognitive impairment. So-called ‘brain fog’ and other impairments that have been found to persist long after the acute phase.”
Using 3 Tesla Magnetic Resonance Spectroscopy (MRS), scientists identified neurochemical abnormalities even when structural imaging findings are normal.
Coronavirus patients’ brains demonstrated N-acetyl-aspartate (NAA) reduction, choline elevation, and Myo-inositol elevation, like what is seen with these metabolites in different patients with white matter abnormalities (leukoencephalopathy) after hypoxia without COVID.
One of the patients with COVID-19 who showed the most severe white matter damage (necrosis and cavitation) had particularly pronounced lactate elevation on MRS, another sign of brain damage from oxygen deprivation.
Two of the three COVID-19 patients were intubated in the intensive care unit at the time of imaging, which was conducted as part of their care. One had COVID-19-associated necrotizing leukoencephalopathy. Another had experienced a recent cardiac arrest and showed subtle white matter changes on structural MR. The third had no clear encephalopathy or recent cardiac arrest.
The non-COVID control cases included one patient with white matter damage because of hypoxia from different causes (post-hypoxic leukoencephalopathy), one with sepsis-related white matter damage, and a normal, age-matched, healthy volunteer.
MGH neuroradiologist Otto Rapalino, who shares the first authorship with Harvard-MGH postdoctoral research fellow Akila Weerasekera said, “A key question is whether it is just the decrease in oxygen to the brain that is causing these white matter changes or whether the virus is itself attacking the white matter.”
“Compared to conventional structural MR imaging, MRS can better characterize pathological processes, such as neuronal injury, inflammation, demyelination, and hypoxia. Based on these findings, we believe it could be used as a disease and therapy monitoring tool.”
- Rapalino, A. Weerasekera et al. Brain MR Spectroscopic Findings in 3 Consecutive Patients with COVID-19: Preliminary Observations. DOI: 10.3174/ajnr.A6877