Diagnostic Imaging's Weekly Scan: May 15, 2020
Welcome back to Diagnostic Imaging’s Weekly Scan. I’m Whitney Palmer, senior editor. We’re back, again, this week to bring you the latest in radiology news and how the COVID-19 outbreak is continuing to impact the specialty and the patients it serves.
A new study published in Radiology this week brought us news that abdominal abnormalities are more common in patients who test positive for COVID-19 than providers had previously known. Investigators from Massachusetts General Hospital conducted a retrospective study, reviewing the ultrasounds, CT scans, and MRIs conducted on 412 patients with viral infection. They discovered a number of bowel abnormalities, including thickening and ischemia, such as pneumatosis and portal venous gas. These conditions occurred most often in patients who had been admitted to the intensive care unit. In addition, surgical correlation revealed unusual yellow discoloration, as well as dead bowel, in some patients. The virus that causes COVID-19 is believed to enter cells through the surface expression of angiotensin converting enzyme 2, they said, making the small bowel particularly vulnerable to direct infection.
A research team from Mount Sinai this week also published findings in Radiology that revealed chest X-ray can effectively detect which young or middle-aged adults will likely end up hospitalized or intubated due to COVID-19. This first-of-its-kind study looked at X-rays from 338 COVID-19-positive patients and examined the images for patterns of coronavirus in the lungs of every patient. They divided the X-rays into six zones and identified opacities and the patterns of where they were located. In addition, they created a 0-to-6 scoring system with 0-to-2 indicating less severe disease, and 3-to-6 reflecting a more critical condition. Of the 145 patients who were admitted to the hospital, the team determined those with the higher severity scores were 6.2 times more likely to require hospitalization, and 4.7 times more likely to be intubated. The investigators said they hope the study results will help with predicting, triaging, and risk-stratifying patients with COVID-19.
Using lung ultrasound to scan COVID-19-positive patients in the intensive care unit daily to monitor their disease progression is an effective way to control the further potential spread of the virus to healthcare personnel. It also limits the need for additional imaging. A team in Italy discussed their “lung ultrasound first” policy in Ultrasound in Medicine & Biology, highlighting that their hospital’s already existing protocol to use ultrasound as the initial screening tool has also worked well when caring for patients infected with this virus. Not only does it minimize the transport of COVID-19-positive patients to the radiology department, but it also reduces the number of bedside X-rays, and limits provider exposure. To determine whether this patient group still required additional imaging, the team compared the number of chest CTs and X-rays performed during their COVID-19 peak to the same time period a year prior. They discovered the median number of chest X-rays dropped from three to one from 2019 to 2020, and the amount of patients who received at least one CT fell from 31.8 percent to 3.6 percent.
So much attention has been given to lung and abdominal imaging during this outbreak, that other types of imaging for different conditions has fallen by the wayside. In the New England Journal of Medicine, a team of investigators from the Washington University School of Medicine in St. Louis discovered that imaging for stroke has dipped 40 percent since the beginning of the pandemic. To make this determination, the group examined approximately 232,000 stroke evaluations at 856 hospitals nationwide, and they measured the number of scans analyzed using Rapid software, a tool frequently used to pinpoint which stroke patients could be good candidates for endovascular therapy based on occlusions of the brain arteries or regions that have potentially reversible ischemia. By comparing two time periods – one pre-outbreak and one during the outbreak, the investigators determined that stroke scans fell during the outbreak from 1.18 patients per day per hospital to 0.72. These findings are important, they said, because the delivery of stroke care is most critical during the first 24 hours after the event.
And, finally, this week, researchers out of Turkey published a study in Radiology that revealed new findings in intensive care unit patients of brain abnormalities identified via MRI that could be caused by COVID-19. Their research revealed that 44 percent of this patient group had exhibited neurological symptoms. They examined 235 patients from two academic and six academic-affiliated hospitals. Fifty of these patients developed neurological symptoms, and 27 received MRI scans. Of that group, 10 patients had acute findings that the team attributed to COVID-19. These abnormalities affected the frontal, parietal, occipital, and temporal lobes, as well as the insular cortex and cingulate gyrus. It is important to note, however, that many in radiology have questioned the strength of the study, pointing to the small number of patients examined and the difficulty in determining whether the abnormalities are truly caused by COVID-19 or could be the result of some other viral infection. Diagnostic Imaging spoke this week with Dr. Pravin George, a neurologist from the Cleveland Clinic about this study and its findings. Here’s what he had to say.