Zhuhai / Guangdong - The severe pneumonia, which can occur as part of an infection with the novel coronavirus (2019-nCoV), is characterized on the computer tomogram (CT) by bilateral milk glass opacities and consolidation of sections of the lung. According to retrospective case series in Radiology (2020;), the “crazy paving” pattern sometimes occurs.
One of the first examinations for suspected pneumonia is computed tomography. The CT can usually not identify the cause of the disease. However, there are patterns that are typical for individual pathogens.
In SARS and MERS, the two other serious diseases caused by coronaviruses, opacities and consolidations are the primary findings. It is also typical that the changes mainly occur in the periphery. A thickening of the interlobular septa and intralobular lines sometimes results in the pattern of disordered pavement, which is known as “crazy paving pattern”.
A team led by Hong Shan from “Sun Yat Sen” University in Zhuhai in Guangdong Province is now presenting the CT results of 21 patients who have been treated in 3 hospitals in China in the past few weeks. The 13 men and 8 women were between 29 and 77 years old. The infection had been proven by laboratory tests in all of them.
The most frequent changes were as with SARS and MERS frosted glass opacities (12 patients) and consolidations (6 patients). In most patients, more than 2 lobes (21 patients) and both lobes (16 patients) were affected.
Secondary findings included milk glass opacities with rounded morphology (7 patients), reticular patterns 83 patients) and the called "crazy paving" (4 patients). A peripheral localization of the opacities was also common (7 patients). In no patient, however, were delineated nodes, cavities, pleural effusions or an enlargement of lymph nodes found.
Interestingly, 3 patients showed no changes in the CT at the initial examination. In one of these patients, 3 days later, demarcated milk glass opacity was found in the right lower lobe of the lung.
According to Shan, it could be the first visible sign of the disease in the lungs. Another patient was still without CT changes at follow-up examination after 4 days. A normal CT finding therefore does not reliably rule out 2019-nCoV disease, warns Shan.