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Updated: Dec 21, 2025

Lung CT Segmentation to Identify Consolidations and Ground Glass Areas for Quantitative Assesment of SARS-CoV Pneumonia
Published on: December 19, 2020
False negative chest X-Rays in patients affected by COVID-19 pneumonia and corresponding chest CT findings
M Cellina1, M Orsi1, T Toluian2
1Department of Radiology, ASST Fatebenefratelli Sacco, P.zza Principessa Clotilde, 3, 20121, Milan, Italy.
Abstract:
Due to the wide availability, rapid execution, low cost, and possibility of being acquired at the patient's bed, chest X-Ray is a fundamental tool in the diagnosis, follow-up and evaluation of the treatment effectiveness of patients with pneumonia, also in the context of COVID-19 infection. However, false negative cases are possible. We report 4 cases of false negative chest X-Rays, in patients who were diagnosed positive for COVID-19 by real-time transverse-transcript-polymerase chain reaction (RT-PCR), and executed chest unenhanced CTs just after the X-Rays, demonstrating signs of COVID-19 pneumonia.
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