Physicians, radiologists review coronavirus imaging findings in lab-confirmed cases

In the face of the ongoing coronavirus epidemic, researchers from China looked back on the imaging findings from a group of patients with lab-confirmed infection. They shared their radiological takeaways in a new study published in the Journal of Infection.

The Feb. 26 review included 149 patients with real-time polymerase chain reaction-confirmed COVID-19 from three different tertiary hospitals in Wenzhou, China—a city with the most confirmed cases outside the Hubei province, which is home to Wuhan. According to the team, their study is the largest multi-center case series of hospitalized patients from one city.

First author Wenjie Yang, with Shanghai Jiao Tong University Medical School-Affiliated Ruijin Hospital, said patients whose imaging showed multifocal peripheral ground glass or mixed opacity with predominance in the lower lung should be considered “highly suspicious” for coronavirus, especially within the first week of symptom onset.

In terms of chest CTs, 287 segments showed ground glass opacity, with 637 cases of mixed opacity and 170 with consolidation. A majority of lesions were localized in the peripheral lung with a “patchy” form, the authors wrote.

The clinicians also noted that their imaging findings are largely similar to results published in other radiology-focused studies, but did say that may vary from person to person.

“Since the form of lesion could be oval sometimes instead of patchy, physicians and radiologists should keep in mind the diversity of imaging presentations of COVID-19,” the authors wrote.

This current epidemic also has overlap with other coronavirus outbreaks, such as severe acute respiratory syndrome coronavirus (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV. Each contained unilateral or bilateral ground-glass opacity or consolidation, but COVID-19 patients have “more extensive GGO than consolidation,” they noted.

Radiologists must also be aware that a normal chest CT does not indicate an individual is free from coronavirus. In fact, 17 patients in their study had a CT scan that was initially normal. Ten days later, however, 12 of those individuals with lab-confirmed infection still had a negative scan.

“This finding suggests that a normal chest CT scan cannot exclude the diagnosis of COVID-19,” they commented. “Therefore, clinicians [and] radiologists should still suspect patients with typical symptoms, such as fever, cough, lymphopenia and exposure history, and give them an RT-PCR test.”

Yang and colleagues found no significant difference in the imaging findings between patients with or without a history of traveling to Hubei. 

The fight to contain coronavirus continues to be a challenge, as the epidemic stretches into the U.S. where there are now 100 confirmed cases and six total deaths. In total, there are now 90,284 cases worldwide and more than 45,000 individuals have recovered from the virus.

Radiologists, and more importantly, computed tomography, remains a key tool in diagnosing patients with COVID-19. Experts have showed the modality is often more accurate than certain lab tests and can detect abnormalities associated with the virus before symptoms appear.