Revealing the dilemma in COVID-19 pneumonia: use of the prone thorax CT imaging in differentiation of opacificities due to dependant zone and pneumonic consolidation.

Abstract

In December 2019, a disease called Coronavirus disease 2019 (COVID-19) caused by the novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS- COV-2) emerged in Wuhan, China. The disease was declared as a pandemic by the WHO on May 11, 2020. The gold standard to diagnose is a Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) test. Additionally, computed tomography (CT) is also very useful in certain cases. A 62-year-old female patient was admitted to the emergency room with fever and joint pain for five days. She had a history of contact with COVID- 19 (+) patient. Unenhanced lung CT performed in the prone position clearly showed nodular infiltrations in the subpleural/peripheral lower lung areas in the right lung. Another 73-year-old female patient was admitted to the emergency room with tiredness and loss of taste for a few days. She had no history of contact with COVID-19 (+) patients. Unenhanced lung CT performed while the patient was in supine position, diffuse nodular opacities in the lower regions of both lungs could hardly be detected. The combined throat nose swab test was positive in both patients. In conclusion, lung CT in prone position is a very valuable method of imaging to show COVID-19 pneumonia; it can distinguish true COVID-19 pneumonia from dependent lung zones in the supine position.

Keywords

• COVID-19
• lung CT in prone position
• gravity-dependent atelectasis

References

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