Researchers have described CT imaging features that aid in the early detection and diagnosis of the coronavirus in a study led by Dr. Michael Chung, M.D., assistant professor in the Department of Diagnostic, Interventional, and Molecular Radiology in the Mount Sinai Health System in New York. The coronavirus, referred to as 2019-nCoV, belongs to a family of viruses that include SARS and MERS.

"Early disease recognition is important not only for prompt implementation of treatment but also for patient isolation and effective public health surveillance, containment, and response," said Chung.

In this retrospective case series, Chung and colleagues set out to characterize the key chest CT imaging findings in a group of patients infected with 2019-nCoV in China with the goal of familiarizing radiologists and clinical teams with the imaging manifestations of this new outbreak.

In January, 21 patients with confirmed 2019-nCoV infection underwent chest CT at three hospitals in three provinces in China. The patients consisted of 13 men and 8 women ranging in age from 29 to 77, with a mean age of 51.2 years. All patients were confirmed positive for infection via laboratory testing of respiratory secretions.

For each patient, the initial CT scan was evaluated for the following characteristics: (1) presence of ground-glass opacities, (2) presence of consolidation, (3) number of lobes affected by ground-glass or consolidative opacities, (4) degree of lobe involvement in addition to overall lung "total severity score," (5) presence of nodules, (6) presence of a pleural effusion, (7) presence of thoracic lymphadenopathy (lymph nodes of abnormal size or morphology), and (8) presence of underlying lung disease such as emphysema or fibrosis. Any other thoracic abnormalities were also noted.

The analysis showed that 2019-nCoV typically manifests on CT with bilateral ground-glass and consolidative pulmonary opacities. Nodular opacities, crazy-paving pattern, and a peripheral distribution of disease may be additional features helpful in early diagnosis. The researchers also noted that lung cavitation, discrete pulmonary nodules, pleural effusions, and lymphadenopathy are characteristically absent in cases of 2019-nCoV. Follow-up imaging in seven of eight patients showed mild or moderate progression of disease as manifested by increasing extent and density of airspace opacities.

Chung cautioned that absence of abnormal CT findings upon initial examination does not rule out the presence of 2019-nCoV.