One in seven COVID-19 patients may experience neurological injury
During the initial phases of the COVID-19 pandemic, it was widely believed that the novel virus was primarily a respiratory illness affecting the lungs. The medical community was warning mostly of respiratory symptoms such as shortness of breath and cough, in addition to other flu-like symptoms, such as fever, fatigue, body aches, chills, and sore throat.
COVID-19: Not Just a Respiratory Illness
Over time, however, the medical community has learned that COVID-19 is much more than a respiratory virus. There’s evidence that it can cause a variety of bizarre symptoms that scientists and doctors are still learning much about, some of which include those that affect the heart, kidneys, and central nervous system (brain and spinal cord). The neurological impact of COVID-19 is highly concerning and neuroradiologists are seeing firsthand some of its devastating effects. In fact, a study published in late 2020 at the NYU Grossman School of Medicine suggests that one in seven people infected with the virus experiences some type of neurological injury.
Studies have shown that a notable percentage of patients who are hospitalized with COVID-19 are experiencing headaches, fatigue and an altered mental status – confusion, agitation, delirium, and memory issues. Some even experience ischemic stroke, caused when an artery to the brain is blocked; seizures; encephalopathy, or altered brain function; and movement disorders associated with the corticospinal tract, a pathway from the brain to the spine that controls movement of the body’s trunk and lungs.
A rare few have also experienced cerebral sinus thrombosis, a blood clot in the brain that leads to stroke, or meningoencephalitis, brain inflammation that causes symptoms such as blurred vision and bodily rash. There has also been an increase in the number of young and middle-aged COVID-19 patients who experience stroke.
Lastly, some patients known as ‘long-haulers’ who have recovered from COVID-19 are experiencing unexplained neurological symptoms months later such as long-term loss of smell (hyposmia), tremors, fatigue, memory loss, and sleep disorders.
Experts aren’t sure exactly what’s causing neurological complications of COVID-19 – it could be either a direct viral invasion from the virus, a post-inflammatory condition based on how the immune system is responding to COVID-19, or simply how the body of a critically-ill patient is responding to the illness.
The Critical Role Radiology Plays in Fighting COVID-19
As COVID-19 continues to spread, imaging studies have become even more critical to the diagnosis and treatment of patients who are suffering from this virus. There now exists a heightened sensitivity and awareness among medical providers that certain symptoms of COVID-19 could be due to neurological complications. This is where neuroradiologists provide an essential piece to the puzzle. They possess the critical tests, tools, and training to assess patients for serious problems and can often provide the pathway toward life-saving treatments.
“We’ve definitely seen an increase in neuroradiology studies as a result of COVID-19,” explains Dr. Peter Tanpitukpongse, a neuroradiologist with Raleigh Radiology. He explains that some patients are experiencing acute problems such as stroke or seizure, while others are looking for answers for unexplained cognitive symptoms like dizziness, confusion, or brain fog.
“The most important thing is to identify if a COVID-19 patient has had a stroke since many stroke treatments can only be administered within a certain number of hours from the onset of symptoms,” explained Dr. Tanpitukpongse.
When Treating Stroke, Diagnosis and Timing Are the Key
Dr. Tanpitukpongse further explained that determining the right treatment for stroke depends on whether the stroke is ischemic or hemorrhagic – and imaging studies are the key to determining the type of stroke that may have occurred.
Four Types of Imaging Studies Used for Stroke Detection
Neuroradiologists use four different types of imaging studies to learn more about what is happening inside of a COVID-19 patient’s brain and to make the quick decisions necessary when it comes to the potential of stroke.
Computed Tomography (CT) Scan – Because it can be performed relatively quickly and is widely available in the office, hospital, and emergency room settings, the CT scan is typically the test chosen as the first line of defense. It uses X-ray and computers to take multiple images of the inside of the head, at multiple angles. Neuroradiologists can use the CT scan to look for signs of ischemic stroke and hemorrhagic stroke.
Magnetic Resonance Imaging (MRI) – MRI is a scan used by neuroradiologists because of its greater sensitivity in detecting stroke. Much more can be seen on an MRI than on a CT scan. MRI is used in the inpatient and outpatient settings and allows the neuroradiologist to use diffusion-weighted imaging (DWI), which is a sensitive and specific MRI sequence that is highly effective and almost immediate in detecting any signs of stroke in the brain.
“The most common test we use from the neuroradiology perspective is the MRI brain exam,” said Dr. Tanpitukpongse. “In addition to identifying stroke, MRI also evaluates for possible alternative explanations for chronic neurological symptoms, for instance, a mass, hemorrhage, stroke, demyelinating disease, etc. The real benefit is to exclude a worrisome underlying condition so that the neurologist or other provider can focus on treating the symptoms.”
CT Angiography (CTA) – This imaging study is mostly performed in an acute setting, where a patient is showing acute signs of stroke from large vessel occlusion, or large blood clots in the head and neck. Importantly, it can determine if a patient is a candidate for treatment, and more specifically, embolectomy. To perform a CTA, the patient is injected with contrast into the body and follows it through the vessels in the neck and head to determine if there is any evidence of occlusion or dissection (a tear).
CTA Perfusion – The CTA perfusion is a relatively new study for patients who have presented to the hospital with stroke-like symptoms up to six hours after symptom onset. The neuroradiologist uses CTA perfusion to look for evidence of ischemic penumbra, an area of the brain that is severely damaged by stroke via decreased oxygen and decreased cerebral blood flow (the amount of blood that flows through the brain per unit of brain tissue).
This test helps determine how much of the brain is salvageable with treatment and how much is irreversibly damaged, also called cerebral infarction. To perform CTA perfusion, the neuroradiologist injects a contrast into the body and analyzes blood flow to the brain to calculate how adequate it is. In addition to other imaging scans, CTA perfusion can aid a neuroradiologist and stroke team in determining if the patient should receive neurointervention (such as embolectomy) versus tPA or other treatment.
To perform imaging scans, Raleigh Radiology and WakeMed Health & Hospitals use RapidAI™ software, advanced specialized imaging for patients who present to the hospital with acute stroke. This automated system allows neuroradiologists to quickly obtain stroke test values and report them to emergency room doctors and the stroke team as soon as possible.
Providing the Best Care Possible in the Age of COVID-19
Dr. Tanpitukpongse concludes by acknowledging that there is still much to learn about the effects of COVID-19 on the brain. “At Raleigh Radiology, our team is committed to continuously reviewing and evaluating all new research and literature that suggest a connection between COVID-19 and neurological disorders so we can provide the best care and treatment possible to our patients.”
Sources:
https://weillcornell.org/news/what-to-know-about-stroke-and-covid-19
https://www.aans.org/en/Patients/Neurosurgical-Conditions-and-Treatments/Stroke
https://www.mayoclinic.org/diseases-conditions/brain-avm/diagnosis-treatment/drc-20350265
https://www.nejm.org/doi/10.1056/NEJMc2008597
https://www.stroke.org/en/about-stroke/treatment/why-getting-quick-stroke-treatment-is-important
http://www.strokecenter.org/patients/about-stroke/ischemic-stroke/
