Review of chest CT manifestations of COVID-19 infection

  • Maria El Homsi
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Michael Chung
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Adam Bernheim
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Adam Jacobi
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Michael J. King
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Sara Lewis
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA

    BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA
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  • Bachir Taouli
    Correspondence
    Corresponding author at: Department of Diagnostic, Molecular and Interventional Radiology, BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, 1470 Madison Avenue, New York, NY, 10029, USA.
    Affiliations
    Department of Diagnostic, Molecular and Interventional Radiology, Icahn School of Medicine at Mount Sinai, New York, USA

    BioMedical Engineering and Imaging Institute, Icahn School of Medicine at Mount Sinai, New York, USA
    Search for articles by this author
Open AccessPublished:June 07, 2020DOI:https://doi.org/10.1016/j.ejro.2020.100239

      Highlights

      • RT-PCR, the standard of reference for diagnosis, has variable sensitivity of 32%–93%.
      • Bilateral peripheral ground-glass opacities are the main chest CT features of COVID-19 pneumonia.
      • CT has excellent sensitivity but limited specificity for diagnosing COVID-19 pneumonia.
      • Chest CT is not recommended for screening of COVID-19 infection.

      Abstract

      Coronavirus disease-19 (COVID-19) is a viral pandemic that started in China and has rapidly expanded worldwide. Typical clinical manifestations include fever, cough and dyspnea after an incubation period of 2–14 days. The diagnosis is based on RT-PCR test through a nasopharyngeal swab. Because of the pulmonary tropism of the virus, pneumonia is often encountered in symptomatic patients. Here, we review the pertinent clinical findings and the current published data describing chest CT findings in COVID-19 pneumonia, the diagnostic performance of CT for diagnosis, including differential diagnosis, as well the evolving role of imaging in this disease.

      Abbreviations:

      ARDS (acute respiratory distress syndrome), CAP (community-acquired pneumonia), COVID-19 (coronavirus disease 2019), CRP (C-Reactive Protein), GGO (ground-glass opacity), MERS (Middle East respiratory syndrome), PUI (patient under investigation), RT-PCR (reverse transcription polymerase chain reaction), SARS (severe acute respiratory syndrome), SARSCoV-2 (severe acute respiratory syndrome coronavirus 2)

      Keywords

      1. Introduction

      COVID-19 is caused by an RNA virus, SARS CoV-2 (severe acute respiratory syndrome coronavirus 2) which is part of the Coronaviridae family (which includes SARS-CoV and MERS(Middle East respiratory syndrome)-CoV) [
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      ]. Most people who contract COVID-19 experience mild symptoms and recover without specific treatment. The typical incubation period ranges between 2–7 days, but can be as long as two weeks. The most common symptoms include fever (reported between 43.8 %–98 %), cough (67.8 %–76 %), headache, malaise, myalgia, and dyspnea [
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      Several biologic findings have been reported: lymphopenia, elevated inflammatory indices such as C-reactive protein (CRP), d-dimer, procalcitonin and ferritin, lactate dehydrogenase (LDH) and interleukin-6 (IL-6); IL-6 in particular may identify cases with poor prognosis and prompt intervention in order to improve outcomes [
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      The course of disease can be described as nonsevere or severe, based on the need for hospitalization for dyspnea, hypoxia, and the possible need for mechanical ventilation. In two Chinese series, most cases were classified as mild (81 %–84.3 %), with16.7 %–19 % of cases being severe (including critical cases) [
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      Characteristics of and Important Lessons From the Coronavirus Disease 2019 (COVID-19) Outbreak in China: Summary of a Report of 72314 Cases From the Chinese Center for Disease Control and Prevention.
      ]. A proportion of 2.3%–12.2% of patients require mechanical ventilation [
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      • Wu Z.
      • McGoogan J.M.
      Characteristics of and Important Lessons From the Coronavirus Disease 2019 (COVID-19) Outbreak in China: Summary of a Report of 72314 Cases From the Chinese Center for Disease Control and Prevention.
      ]. The reported mortality rates vary between 1.4 % and 28 %, depending on the series [
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      Presenting characteristics, comorbidities, and outcomes among 5700 patients hospitalized with COVID-19 in the New York City Area.
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      Characteristics of and Important Lessons From the Coronavirus Disease 2019 (COVID-19) Outbreak in China: Summary of a Report of 72314 Cases From the Chinese Center for Disease Control and Prevention.
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      3. Diagnostic confirmation of COVID-19

      The two commonly used detection methods for SARS-CoV-2 are real-time reverse transcription polymerase chain reaction (RT-PCR) and high-throughput sequencing. High-throughput sequencing of the whole genome has a limited role clinically because of its high cost [
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      • Jiang R.D.
      • Liu M.Q.
      • Chen Y.
      • Shen X.R.
      • Wang X.
      • Zheng X.S.
      • Zhao K.
      • Chen Q.J.
      • Deng F.
      • Liu L.L.
      • Yan B.
      • Zhan F.X.
      • Wang Y.Y.
      • Xiao G.F.
      • Shi Z.L.
      A pneumonia outbreak associated with a new coronavirus of probable bat origin.
      ]. RT-PCR (which detects the viral nucleic acids when present in sufficient quantity) is the most commonly used method for diagnosis in respiratory secretions [
      • Corman V.M.
      • Landt O.
      • Kaiser M.
      • Molenkamp R.
      • Meijer A.
      • Chu D.K.
      • Bleicker T.
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      • Schneider J.
      • Schmidt M.L.
      • Mulders D.G.
      • Haagmans B.L.
      • van der Veer B.
      • van den Brink S.
      • Wijsman L.
      • Goderski G.
      • Romette J.L.
      • Ellis J.
      • Zambon M.
      • Peiris M.
      • Goossens H.
      • Reusken C.
      • Koopmans M.P.
      • Drosten C.
      Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR.
      ,
      • Chan J.F.
      • Yip C.C.
      • To K.K.
      • Tang T.H.
      • Wong S.C.
      • Leung K.H.
      • Fung A.Y.
      • Ng A.C.
      • Zou Z.
      • Tsoi H.W.
      • Choi G.K.
      • Tam A.R.
      • Cheng V.C.
      • Chan K.H.
      • Tsang O.T.
      • Yuen K.Y.
      Improved molecular diagnosis of COVID-19 by the novel, highly sensitive and specific COVID-19-RdRp/Hel real-time reverse Transcription-PCR assay validated in vitro and with clinical specimens.
      ]. The largest study published on RT-PCR detection in various samples demonstrated positive rates between 32 %–93 % in the nasopharynx and upper respiratory tract (lowest in the pharynx, and highest in bronchoalveolar lavage fluid specimen), while nasal swabs had a 63 % positive rate [
      • Wang W.
      • Xu Y.
      • Gao R.
      • Lu R.
      • Han K.
      • Wu G.
      • Tan W.
      Detection of SARS-CoV-2 in different types of clinical specimens.
      ]. The variation in positive rates may be explained by date of sampling (too early or too late), improper sampling, low viral load and difference of detection rate from different manufacturers [
      • Fang Y.
      • Zhang H.
      • Xie J.
      • Lin M.
      • Ying L.
      • Pang P.
      • Ji W.
      Sensitivity of chest CT for COVID-19: comparison to RT-PCR.
      ].
      Serum immunoglobulins (IgM and IgG) can be used to diagnose recent infection to COVID-19 [
      • Amanat F.
      • Stadlbauer D.
      • Strohmeier S.
      • Nguyen T.
      • Chromikova V.
      • McMahon M.
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      A serological assay to detect SARS-CoV-2 seroconversion in humans.
      ]. For example, a study demonstrated that the positive detection rate is increased (98.6 %) when combining IgM assay with RT-PCR compared to RT-PCR alone (51.9 %) [
      • Guo L.
      • Ren L.
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      Profiling early humoral response to diagnose novel coronavirus disease (COVID-19).
      ].

      4. Imaging findings of COVID-19

      A total of 30 original papers published in English totaling over 4000 patients were reviewed [
      • Fang Y.
      • Zhang H.
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      • Pang P.
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      Sensitivity of chest CT for COVID-19: comparison to RT-PCR.
      ,
      • Shi H.
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      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
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      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
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      • Yang Y.
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      • Zhang N.
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      • Li K.
      • Li S.
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      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
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      • Qin L.
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      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Yang W.
      • Sirajuddin A.
      • Zhang X.
      • Liu G.
      • Teng Z.
      • Zhao S.
      • Lu M.
      The role of imaging in 2019 novel coronavirus pneumonia (COVID-19).
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Xie X.
      • Zhong Z.
      • Zhao W.
      • Zheng C.
      • Wang F.
      • Liu J.
      Chest CT for typical 2019-nCoV pneumonia: relationship to negative RT-PCR testing.
      ,
      • Himoto Y.
      • Sakata A.
      • Kirita M.
      • Hiroi T.
      • Kobayashi K.I.
      • Kubo K.
      • Kim H.
      • Nishimoto A.
      • Maeda C.
      • Kawamura A.
      • Komiya N.
      • Umeoka S.
      Diagnostic performance of chest CT to differentiate COVID-19 pneumonia in non-high-epidemic area in Japan.
      ,
      • Pan F.
      • Ye T.
      • Sun P.
      • Gui S.
      • Liang B.
      • Li L.
      • Zheng D.
      • Wang J.
      • Hesketh R.L.
      • Yang L.
      • Zheng C.
      Time Course of Lung Changes On Chest CT During Recovery From 2019 Novel Coronavirus (COVID-19) Pneumonia.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ,
      • Yang W.
      • Cao Q.
      • Qin L.
      • Wang X.
      • Cheng Z.
      • Pan A.
      • Dai J.
      • Sun Q.
      • Zhao F.
      • Qu J.
      • Yan F.
      Clinical characteristics and imaging manifestations of the 2019 novel coronavirus disease (COVID-19):a multi-center study in Wenzhou city, Zhejiang, China.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ,
      • Lomoro P.
      • Verde F.
      • Zerboni F.
      • Simonetti I.
      • Borghi C.
      • Fachinetti C.
      • Natalizi A.
      • Martegani A.
      COVID-19 pneumonia manifestations at the admission on chest ultrasound, radiographs, and CT: single-center study and comprehensive radiologic literature review.
      ]. Reviews and case reports were excluded. Most reviewed papers originate from China [
      • Fang Y.
      • Zhang H.
      • Xie J.
      • Lin M.
      • Ying L.
      • Pang P.
      • Ji W.
      Sensitivity of chest CT for COVID-19: comparison to RT-PCR.
      ,
      • Shi H.
      • Han X.
      • Jiang N.
      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
      • Zheng C.
      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Xie X.
      • Zhong Z.
      • Zhao W.
      • Zheng C.
      • Wang F.
      • Liu J.
      Chest CT for typical 2019-nCoV pneumonia: relationship to negative RT-PCR testing.
      ,
      • Pan F.
      • Ye T.
      • Sun P.
      • Gui S.
      • Liang B.
      • Li L.
      • Zheng D.
      • Wang J.
      • Hesketh R.L.
      • Yang L.
      • Zheng C.
      Time Course of Lung Changes On Chest CT During Recovery From 2019 Novel Coronavirus (COVID-19) Pneumonia.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ,
      • Yang W.
      • Cao Q.
      • Qin L.
      • Wang X.
      • Cheng Z.
      • Pan A.
      • Dai J.
      • Sun Q.
      • Zhao F.
      • Qu J.
      • Yan F.
      Clinical characteristics and imaging manifestations of the 2019 novel coronavirus disease (COVID-19):a multi-center study in Wenzhou city, Zhejiang, China.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ] and the remainder from Japan [
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ,
      • Himoto Y.
      • Sakata A.
      • Kirita M.
      • Hiroi T.
      • Kobayashi K.I.
      • Kubo K.
      • Kim H.
      • Nishimoto A.
      • Maeda C.
      • Kawamura A.
      • Komiya N.
      • Umeoka S.
      Diagnostic performance of chest CT to differentiate COVID-19 pneumonia in non-high-epidemic area in Japan.
      ], Korea [
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ], Italy [
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Lomoro P.
      • Verde F.
      • Zerboni F.
      • Simonetti I.
      • Borghi C.
      • Fachinetti C.
      • Natalizi A.
      • Martegani A.
      COVID-19 pneumonia manifestations at the admission on chest ultrasound, radiographs, and CT: single-center study and comprehensive radiologic literature review.
      ] and the US add Ref [
      • Toussie D.
      • Voutsinas N.
      • Finkelstein M.
      • Cedillo M.A.
      • Manna S.
      • Maron S.Z.
      • Jacobi A.
      • Chung M.
      • Bernheim A.
      • Eber C.
      • Concepcion J.
      • Fayad Z.
      • Gupta Y.S.
      Clinical and Chest Radiography Features Determine Patient Outcomes In Young and Middle Age adults with COVID-19.
      ]. Three papers were in collaboration between Chinese and US institutions [
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ].

      4.1 Chest radiography findings

      Chest radiography (CXR) findings in patients with COVID-19 have been described in small case series [
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ]. CXR is negative in 40 %–66.7 % of cases despite positive findings on chest CT (Fig. 1) [
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ]. The most common radiographic finding is opacification, often with a peripheral and lower lung distribution [
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ] (Fig. 2). Thus, CXR is not recommended for routine diagnosis of COVID-19, but may be helpful for follow-up.
      Fig. 1
      Fig. 125-year-old female presenting to the emergency department (ED) with 7 days of fever and shortness of breath, with portable chest radiography (a) showing no abnormality. A subsequent CT angiogram of the chest (b) shows multifocal lower lobe rounded opacities, predominately ground-glass in attenuation (arrows). Patient tested positive for COVID-19.
      Fig. 2
      Fig. 260-year-old male with fever and cough for 7 days due to COVID-19. (a) Antero-posterior chest radiography shows ill-defined opacities in the lateral aspect of the right lung (arrows). (b) Axial noncontrast chest CT shows GGOs with a peripheral distribution in both upper lobes (arrows). There is superimposed interlobular and intralobular septal thickening (crazy-paving pattern). (c) Reconstructed coronal chest CT image shows corresponding multifocal bilateral ground-glass opacities with a peripheral distribution (arrows).

      4.2 Chest CT findings

      A low dose, chest CT without intravenous contrast is generally used for evaluation [
      • Kang Z.
      • Li X.
      • Zhou S.
      Recommendation of low-dose CT in the detection and management of COVID-2019.
      ]. Typically, COVID-19 pneumonia presents with bilateral peripheral patchy ground-glass opacities (GGO) with or without consolidation [
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Jajodia A.
      • Ebner L.
      • Heidinger B.
      • Chaturvedi A.
      • Prosch H.
      Imaging in corona virus disease 2019 (COVID-19)—A scoping review.
      ] (Fig. 2, Fig. 3). GGOs may have a rounded morphology [
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ] in up to 54 % of the cases (Fig. 4). Superimposed interlobular septal thickening can also be present, resulting in a crazy-paving pattern (Fig. 2). Vascular enlargement, air bronchograms, and a halo sign have also been described (Fig. 2). The GGOs and consolidative lesions are larger than 1cm in 91 % of cases [
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ]. The lower lobes and posterior portions are more frequently involved [
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ]. Mediastinal and hilar lymphadenopathy, pleural effusions or thickening, discrete pulmonary nodules, and pulmonary cavitation have been rarely described in the Chinese series [
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ]. An Italian study described lymphadenopathy in up to 58 % of cases [
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]. Table 1 shows the prevalence of various imaging findings on chest CT at initial presentation.
      Fig. 3
      Fig. 374 year-old male with fever and cough due to COVID-19. (a) Axial and (b) coronal CT angiography of the chest shows multifocal bilateral ground-glass (white arrow) and consolidative (black arrow) opacities.
      Fig. 4
      Fig. 437-year-old male presenting with fever, cough and dyspnea for 7 days due to COVID-19. (a) Axial chest CT image shows multifocal bilateral GGOs with a rounded morphology (arrows). (b) Corresponding coronal CT shows the bilateral ground-glass lesions, many of which are peripheral in distribution as well.
      Table 1Reported prevalence of imaging findings of COVID-19 on chest CT.
      Imaging findingsMean (Range in %)References
      Common features
      Ground glass opacities (GGO)71.7 (27.3−100)[
      • Shi H.
      • Han X.
      • Jiang N.
      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
      • Zheng C.
      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ]
      Crazy-paving26.7 (5−89.4)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ]
      Enlarged subsegmental vessels80.9 (71.3−89)[
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]
      Rounded morphology34 (11−59.6)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]
      Consolidation41.2 (6−69)[
      • Guan W.J.
      • Ni Z.Y.
      • Hu Y.
      • Liang W.H.
      • Ou C.Q.
      • He J.X.
      • Liu L.
      • Shan H.
      • Lei C.L.
      • Hui D.S.C.
      • Du B.
      • Li L.J.
      • Zeng G.
      • Yuen K.Y.
      • Chen R.C.
      • Tang C.L.
      • Wang T.
      • Chen P.Y.
      • Xiang J.
      • Li S.Y.
      • Wang J.L.
      • Liang Z.J.
      • Peng Y.X.
      • Wei L.
      • Liu Y.
      • Hu Y.H.
      • Peng P.
      • Wang J.M.
      • Liu J.Y.
      • Chen Z.
      • Li G.
      • Zheng Z.J.
      • Qiu S.Q.
      • Luo J.
      • Ye C.J.
      • Zhu S.Y.
      • Zhong N.S.
      China Medical Treatment Expert Group for, Clinical Characteristics of Coronavirus Disease 2019 in China.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ]
      GGO and consolidation46.6 (29−64.4)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ]
      Interlobular septal thickening50.9 (13−75)[
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]
      Halo sign34.3 (12−69)[
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ]
      Air bronchogram50 (8−80)[
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ]
      Distribution
      Posterior80 (67−93)[
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]
      Bilateral79.2 (51−93)[
      • Shi H.
      • Han X.
      • Jiang N.
      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
      • Zheng C.
      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ,
      • Ai T.
      • Yang Z.
      • Hou H.
      • Zhan C.
      • Chen C.
      • Lv W.
      • Tao Q.
      • Sun Z.
      • Xia L.
      Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ]
      Peripheral73 (43.6−100)[
      • Shi H.
      • Han X.
      • Jiang N.
      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
      • Zheng C.
      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Yoon S.H.
      • Lee K.H.
      • Kim J.Y.
      • Lee Y.K.
      • Ko H.
      • Kim K.H.
      • Park C.M.
      • Kim Y.H.
      Chest radiographic and CT findings of the 2019 novel coronavirus disease (COVID-19): analysis of nine patients treated in Korea.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ]
      More than 2 lobes affected62.5 (51−93)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ]
      Central and peripheral distribution19.9 (2−56.4)[
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ]
      Uncommon Findings
      Centrilobular nodules15.7 (0−32)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ]
      Tree-in-bud nodularity9.1[
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ]
      Bronchiectasis30.9 (1−52.5)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ]
      Bronchial wall thickening10.5 (0−28.7)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ]
      Cystic changes9.1[
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ]
      Pleural thickening30 (0−56)[
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ]
      Subpleural linear opacity18.2 (17.5−33.9)[
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Pan F.
      • Ye T.
      • Sun P.
      • Gui S.
      • Liang B.
      • Li L.
      • Zheng D.
      • Wang J.
      • Hesketh R.L.
      • Yang L.
      • Zheng C.
      Time Course of Lung Changes On Chest CT During Recovery From 2019 Novel Coronavirus (COVID-19) Pneumonia.
      ]
      Reverse halo sign5.1 (3.9−17)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ]
      Pleural effusion3.7 (0−13.9)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ]
      Pericardial effusion3.4 (1−6)[
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ]
      Lymphadenopathy5.8 (0−58)[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Cheng Z.
      • Lu Y.
      • Cao Q.
      • Qin L.
      • Pan Z.
      • Yan F.
      • Yang W.
      Clinical Features and Chest CT Manifestations of Coronavirus Disease 2019 (COVID-19) in a Single-Center Study in Shanghai, China.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Guan C.S.
      • Lv Z.B.
      • Yan S.
      • Du Y.N.
      • Chen H.
      • Wei L.G.
      • Xie R.M.
      • Chen B.D.
      Imaging features of coronavirus disease 2019 (COVID-19): evaluation on thin-section CT.
      ,
      • Li Y.
      • Xia L.
      Coronavirus Disease 2019 (COVID-19): Role of Chest CT in Diagnosis and Management.
      ,
      • Song F.
      • Shi N.
      • Shan F.
      • Zhang Z.
      • Shen J.
      • Lu H.
      • Ling Y.
      • Jiang Y.
      • Shi Y.
      Emerging 2019 Novel Coronavirus (2019-nCoV) Pneumonia.
      ,
      • Wu J.
      • Wu X.
      • Zeng W.
      • Guo D.
      • Fang Z.
      • Chen L.
      • Huang H.
      • Li C.
      Chest CT Findings in Patients with Corona Virus Disease 2019 and its Relationship with Clinical Features.
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ,
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Bai H.X.
      • Hsieh B.
      • Xiong Z.
      • Halsey K.
      • Choi J.W.
      • Tran T.M.L.
      • Pan I.
      • Shi L.B.
      • Wang D.C.
      • Mei J.
      • Jiang X.L.
      • Zeng Q.H.
      • Egglin T.K.
      • Hu P.F.
      • Agarwal S.
      • Xie F.
      • Li S.
      • Healey T.
      • Atalay M.K.
      • Liao W.H.
      Performance of radiologists in differentiating COVID-19 from viral pneumonia on chest CT.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ,
      • Zhu W.
      • Xie K.
      • Lu H.
      • Xu L.
      • Zhou S.
      • Fang S.
      Initial clinical features of suspected coronavirus disease 2019 in two emergency departments outside of Hubei, China.
      ]
      Lung Cavitation0[
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Chung M.
      • Bernheim A.
      • Mei X.
      • Zhang N.
      • Huang M.
      • Zeng X.
      • Cui J.
      • Xu W.
      • Yang Y.
      • Fayad Z.A.
      • Jacobi A.
      • Li K.
      • Li S.
      • Shan H.
      CT imaging features of 2019 novel coronavirus (2019-nCoV).
      ,
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Caruso D.
      • Zerunian M.
      • Polici M.
      • Pucciarelli F.
      • Polidori T.
      • Rucci C.
      • Guido G.
      • Bracci B.
      • de Dominicis C.
      • Laghi A.
      Chest CT features of COVID-19 in Rome, Italy.
      ,
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Xu X.
      • Yu C.
      • Qu J.
      • Zhang L.
      • Jiang S.
      • Huang D.
      • Chen B.
      • Zhang Z.
      • Guan W.
      • Ling Z.
      • Jiang R.
      • Hu T.
      • Ding Y.
      • Lin L.
      • Gan Q.
      • Luo L.
      • Tang X.
      • Liu J.
      Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2.
      ]
      A Japanese study described that asymptomatic patients tend to have more GGO (80 %) and less consolidation (20 %) compared with symptomatic patients (63 % and 38 %) [
      • Inui S.
      • Fujikawa A.
      • Jitsu M.
      • Kunishima N.
      • Watanabe S.
      • Suzuki Y.
      • Umeda S.
      • Uwabe Y.
      Chest CT findings in cases from the cruise ship “diamond princess” with coronavirus disease 2019 (COVID-19).
      ]. CXR and chest CT can be negative in up to 17.9 % of patients, especially in early and/or non severe disease [
      • Guan W.J.
      • Ni Z.Y.
      • Hu Y.
      • Liang W.H.
      • Ou C.Q.
      • He J.X.
      • Liu L.
      • Shan H.
      • Lei C.L.
      • Hui D.S.C.
      • Du B.
      • Li L.J.
      • Zeng G.
      • Yuen K.Y.
      • Chen R.C.
      • Tang C.L.
      • Wang T.
      • Chen P.Y.
      • Xiang J.
      • Li S.Y.
      • Wang J.L.
      • Liang Z.J.
      • Peng Y.X.
      • Wei L.
      • Liu Y.
      • Hu Y.H.
      • Peng P.
      • Wang J.M.
      • Liu J.Y.
      • Chen Z.
      • Li G.
      • Zheng Z.J.
      • Qiu S.Q.
      • Luo J.
      • Ye C.J.
      • Zhu S.Y.
      • Zhong N.S.
      China Medical Treatment Expert Group for, Clinical Characteristics of Coronavirus Disease 2019 in China.
      ]. In mild cases, CT findings consist more frequently of GGO alone (65 %), followed by GGO with consolidation (44 %) [
      • Han R.
      • Huang L.
      • Jiang H.
      • Dong J.
      • Peng H.
      • Zhang D.
      Early Clinical and CT Manifestations of Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ]. Severe cases with a clinical acute respiratory distress syndrome (ARDS) picture present with widespread dense consolidative opacification on CT (see below).

      4.3 Stages of COVID-19 on chest CT

      Several studies categorized COVID-19 CT findings into several stages based on time since the onset of symptoms [
      • Pan L.
      • Mu M.
      • Yang P.
      • Sun Y.
      • Wang R.
      • Yan J.
      • Li P.
      • Hu B.
      • Wang J.
      • Hu C.
      • Jin Y.
      • Niu X.
      • Ping R.
      • Du Y.
      • Li T.
      • Xu G.
      • Hu Q.
      • Tu L.
      Clinical characteristics of COVID-19 patients with digestive symptoms in Hubei, China: a descriptive, cross-sectional, multicenter study.
      ,
      • Shi H.
      • Han X.
      • Jiang N.
      • Cao Y.
      • Alwalid O.
      • Gu J.
      • Fan Y.
      • Zheng C.
      Radiological findings from 81 patients with COVID-19 pneumonia in Wuhan, China: a descriptive study.
      ,
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ,
      • Wang K.
      • Kang S.
      • Tian R.
      • Zhang X.
      • Zhang X.
      • Wang Y.
      Imaging manifestations and diagnostic value of chest CT of coronavirus disease 2019 (COVID-19) in the Xiaogan area.
      ,
      • Zhou S.
      • Wang Y.
      • Zhu T.
      • Xia L.
      CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
      ]. These were classified into 4 main successive stages: early, intermediate and late [
      • Bernheim A.
      • Mei X.
      • Huang M.
      • Yang Y.
      • Fayad Z.A.
      • Zhang N.
      • Diao K.
      • Lin B.
      • Zhu X.
      • Li K.
      • Li S.
      • Shan H.
      • Jacobi A.
      • Chung M.
      Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
      ] and a fourth resorptive stage [
      • Pan F.
      • Ye T.
      • Sun P.
      • Gui S.
      • Liang B.
      • Li L.
      • Zheng D.
      • Wang J.
      • Hesketh R.L.
      • Yang L.
      • Zheng C.
      Time Course of Lung Changes On Chest CT During Recovery From 2019 Novel Coronavirus (COVID-19) Pneumonia.
      ].
      • Early stage (≤2 days): More than half of the patients have negative chest CT (56 %). The remaining patients have predominantly GGO (44 %) and consolidation (17 %). Imaging findings when present were often unilateral [
        • Bernheim A.
        • Mei X.
        • Huang M.
        • Yang Y.
        • Fayad Z.A.
        • Zhang N.
        • Diao K.
        • Lin B.
        • Zhu X.
        • Li K.
        • Li S.
        • Shan H.
        • Jacobi A.
        • Chung M.
        Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
        ]. Similar findings were described in another study [
        • Zhou S.
        • Wang Y.
        • Zhu T.
        • Xia L.
        CT Features of Coronavirus Disease 2019 (COVID-19) Pneumonia in 62 Patients in Wuhan, China.
        ], which demonstrated that in early disease 16.1 % of cases present with a solitary lesion seen in 70 % of cases in the right lower lobe.
      • Intermediate stage (3–5 days): As the disease progresses, more GGO (88 %) and consolidation (55 %) are noted bilaterally (76 %) and with a peripheral lung distribution (64 %). Only 9% of patients have negative chest CT [
        • Bernheim A.
        • Mei X.
        • Huang M.
        • Yang Y.
        • Fayad Z.A.
        • Zhang N.
        • Diao K.
        • Lin B.
        • Zhu X.
        • Li K.
        • Li S.
        • Shan H.
        • Jacobi A.
        • Chung M.
        Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
        ].
      • Late phase (6–12 days): Most of the patients in this phase have positive chest CT findings. 88 % and 60 % of patients have GGO and consolidation, respectively. The imaging findings are bilateral in 88 % and peripheral-predominant in 72 % of cases [
        • Bernheim A.
        • Mei X.
        • Huang M.
        • Yang Y.
        • Fayad Z.A.
        • Zhang N.
        • Diao K.
        • Lin B.
        • Zhu X.
        • Li K.
        • Li S.
        • Shan H.
        • Jacobi A.
        • Chung M.
        Chest CT findings in coronavirus Disease-19 (COVID-19): relationship to duration of infection.
        ].
      • Absorption stage/fourth stage (>14 days): 65 % and 75 % of patients have GGO and consolidation, respectively. The imaging findings are bilateral in 88 % and peripheral-predominant in 72 % of cases [
        • Pan F.
        • Ye T.
        • Sun P.
        • Gui S.
        • Liang B.
        • Li L.
        • Zheng D.
        • Wang J.
        • Hesketh R.L.
        • Yang L.
        • Zheng C.
        Time Course of Lung Changes On Chest CT During Recovery From 2019 Novel Coronavirus (COVID-19) Pneumonia.
        ].
      When patients improve, the lung disease evolves and organizes, and fibrous bands may appear [
      • Xu Y.H.
      • Dong J.H.
      • An W.M.
      • Lv X.Y.
      • Yin X.P.
      • Zhang J.Z.
      • Dong L.
      • Ma X.
      • Zhang H.J.
      • Gao B.L.
      Clinical and computed tomographic imaging features of novel coronavirus pneumonia caused by SARS-CoV-2.
      ,
      • Zhou Z.
      • Guo D.
      • Li C.
      • Fang Z.
      • Chen L.
      • Yang R.
      • Li X.
      • Zeng W.
      Coronavirus disease 2019: initial chest CT findings.
      ,
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ,
      • Sun Q.
      • Xu X.
      • Xie J.
      • Li J.
      • Huang X.
      Evolution of Computed Tomography Manifestations in Five Patients Who Recovered from Coronavirus Disease 2019 (COVID-19) Pneumonia.
      ]. A “reverse-halo sign” is occasionally observed and can be an indication of organizing pneumonia [
      • Ng M.-Y.
      • Lee E.Y.
      • Yang J.
      • Yang F.
      • Li X.
      • Wang H.
      • Lui M.M.-s.
      • Lo C.S.-Y.
      • Leung B.
      • Khong P.-L.
      • Hui C.K.-M.
      • Yuen K.-y.
      • Kuo M.D.
      Imaging profile of the COVID-19 infection: radiologic findings and literature review.
      ,
      • Kong W.
      • Agarwal P.P.
      Chest imaging appearance of COVID-19 infection.
      ]. In severe cases, the consolidation and GGO increase and involve all five lung lobes, resulting in a dense consolidative appearance and characterized by diffuse alveolar damage, usually with a poor prognosis [
      • Pan Y.
      • Guan H.
      • Zhou S.
      • Wang Y.
      • Li Q.
      • Zhu T.
      • Hu Q.
      • Xia L.
      Initial CT findings and temporal changes in patients with the novel coronavirus pneumonia (2019-nCoV): a study of 63 patients in Wuhan, China.
      ] (Fig. 5)
      Fig. 5
      Fig. 565-year-old female presenting with fever and dyspnea due to COVID-19. (a) Initial ED anteroposterior chest radiography with corresponding (b) coronal chest CT reformatted image show multifocal mid to lower lung predominant ground-glass and consolidative opacities. (c) Follow-up (c) anteroposterior chest radiography and (d) coronal CT reformatted image on day 14 of admission show progressive pulmonary opacities, now more consolidative and involving more of the upper lobes bilaterally.

      4.4 Prediction of severity with imaging

      It has been suggested that imaging can help predict severity of COVID-19 disease. For example, a study showed that a severity score based on CXR at initial presentation in non-elderly patients (21−50y) predicts outcome (hospital admission and intubation) [
      • Toussie D.
      • Voutsinas N.
      • Finkelstein M.
      • Cedillo M.A.
      • Manna S.
      • Maron S.Z.
      • Jacobi A.
      • Chung M.
      • Bernheim A.
      • Eber C.
      • Concepcion J.
      • Fayad Z.
      • Gupta Y.S.
      Clinical and Chest Radiography Features Determine Patient Outcomes In Young and Middle Age adults with COVID-19.
      ]. Another study suggested that severe/fatal cases were more likely to have more extensive and diffuse disease with more frequent architectural distortion and bronchiectasis compared to mild/common cases [
      • Zhao W.
      • Zhong Z.
      • Xie X.
      • Yu Q.
      • Liu J.
      Relation between chest CT findings and clinical conditions of coronavirus disease (COVID-19) pneumonia: a multicenter study.
      ]. However, more data is needed particularly in comparison with blood tests, such as cytokine levels.

      4.5 COVID-19 in special populations

      Oncology patients: A retrospective study in 28 oncologic patients showed similar findings of GGO (75 %) and patchy consolidation (46.3 %). The presence of the latter at admission was associated with worse outcome [
      • Zhang L.
      • Zhu F.
      • Xie L.
      • Wang C.
      • Wang J.
      • Chen R.
      • Jia P.
      • Guan H.Q.
      • Peng L.
      • Chen Y.
      • Peng P.
      • Zhang P.
      • Chu Q.
      • Shen Q.
      • Wang Y.
      • Xu S.Y.
      • Zhao J.P.
      • Zhou M.
      Clinical characteristics of COVID-19-infected cancer patients: a retrospective case study in three hospitals within Wuhan, China.