Table 1.
Overview of studies on CT imaging that have five or more cases of COVID-19.
| References | No. of cases | CT findings | Other findings |
|---|---|---|---|
| Ai et al. (2020) [129] | 1014 | GGOs, consolidation, reticulation/thickened interlobular septa and nodular lesions | Chest CT has a high sensitivity for the diagnosis of COVID-19. |
| Besutti et al. (2020) [130] | 696 | GGO and consolidation | CT showed a high positive predictive value and sensitivity for COVID-19 pneumonia compared with RT-PCR. |
| Zhang et al. (2020) [53] | 645 | GGOs and consolidation | Combing clinical features and radiographic scores can effectively predict severe/critical types. |
| Ling et al. (2020) [50] | 295 | Four patients with COVID-19 infection showed no clinical symptoms or abnormal chest CT images | The clinical symptoms and radiological abnormalities are not the essential components of COVID-19 infection. |
| Liu et al. (2020) [131] | 276 | GGO, consolidation, GGO with consolidation, nodule, patchy shadowing, lineal shadowing, air bronchogram sign, interlobular septal thickening, adjacent pleura thickening, crazy-paving pattern and bronchodilation | The common chest CT signs of COVID-19 pneumonia after exacerbation were ground glass opacity (GGO) with consolidation, bilateral distribution, and multifocal lesions. |
| Yang et al. (2020) [132] | 273 | GGOs, consolidation and linear opacities, solid nodules, fibrous stripes, chronic inflammatory manifestation, chronic bronchitis, emphysema, pericardial effusion, pleural effusion, bullae of lung and obsolete tuberculosis | Age, Monocyte-lymphocyte ratio, homocysteine and period from onset to admission could predict imaging progression on chest CT from COVID-19 patients. |
| Li et al. (2020) [133] | 154 COVID-19 and 100 non-COVID-19 | GGO and consolidation | A peripheral distribution, a lesion range > 10 cm, involvement of 5 lobes, presence of hilar and mediastinal lymph node enlargement, and no pleural effusion were significantly associated with COVID-19. |
| Colombi et al. (2020) [134] | 236 | Patchy GGO, diffuse GGO, GGO and consolidation, pleural effusion, mediastinal nodes enlargement, emphysema and pulmonary fibrosis | In patients with confirmed COVID-19 pneumonia, visual or software quantification the extent of CT lung abnormality were predictors of ICU admission or death. |
| Dai et al. (2020) [38] | 234 | Vascular enhancement sign, interlobular septal thickening, air bronchus sign, intralesional and/or perilesional bronchiectasis, pleural thickening, solid nodules, reticular/mosaic sign, interlobar fissure displacement, bronchial wall thickening, minor pleural effusion, pericardial effusion and mediastinal lymphadenopathy | Chest High-resolution CT provided the distribution, shape, attenuation and extent of lung lesions, and some typical CT signs of COVID-19 pneumonia. |
| Bai et al. (2020) [135] | 219 | GGO, fine reticular opacity and vascular thickening | High specificity but moderate sensitivity in distinguishing COVID-19 from viral pneumonia on chest CT. |
| Liu et al. (2020) [136] | 122 COVID-19 and 48 non-COVID-19 | GGO, GGO with consolidation, consolidation, linear opacities, rounded opacities, crazy paving pattern, halo sign, nodules, tree-in-bud sign, air bronchogram, interlobular septal thickening, bronchiolar wall thickening, pleural effusion, pericardial effusion and lymphadenopathy | There are significant differences in the CT manifestations of patients with COVID-19 and influenza. |
| Caruso et al. (2020) [137] | 158 | GGO, subsegmental vessel enlargement, consolidation, lymphadenopathy, bronchiectasis, air bronchogram, pulmonary nodules surrounded by GGO, interlobular septal thickening, halo sign, pericardial effusion, pleural effusion and bronchial wall thickening | Chest CT sensitivity was high (97%) but with lower specificity (56%). |
| Fan et al. (2020) [138] | 150 | Ground-glass nodules, patchy GGO, consolidation, cord-like lesions, thickening of the bronchovascular bundles, pleural thickening, crazy-paving sign, air bronchogram sign, pleural effusion and enlarged lymph nodes | The main manifestations of initial chest CT in COVID-19 is GGOs, commonly involving single site in patients < 35 years old and multiple sites and extensive area in patients > 60 years old. |
| Yang et al. (2020) [51] | 149 | GGO, mixed GGOs and consolidation, consolidation, air bronchogram, centrilobular nodules, tree-in-bud, reticular pattern, subpleural linear opacity, bronchial dilatation, cystic change, lymphadenopathy and pleural effusion | Some patients with COVID-19 can present with normal chest findings. |
| Chen et al. (2020) [139] | 70 COVID-19 and 66 non-COVID-19 | Pure GGO, mixed GGO, consolidation, pleural traction sign, bronchial wall thickening, interlobular septal thickening, crazy paving, tree-in-bud, pleural effusions, pleural thickening and the offending vessel augmentation in lesions | The pneumonia patients with and without COVID-19 can be distinguished based on CT imaging and clinical records. |
| Li et al. (2020) [140] | 131 | GGOs, consolidation, nodule, interlobular septal thickening, vascular enlargement, air bronchogram, fibrosis, pleural thickening, hydrothorax and lymph node enlargement | The imaging pattern of multifocal peripheral ground glass or mixed consolidation is highly suspicious of COVID-19, that can quickly change over a short period. |
| Wu et al. (2020) [141] | 130 | GGO, GGO with consolidation, vascular thickening, pleural parallel sign, intralobular septal thickening, halo sign, reversed-halo sign, pleural effusion and pneumatocele | COVID-19 imaging characteristic mainly has subpleural, centrilobular and diffused distribution. The first two distributions can overlap or progress to diffused distribution. In the later period, it was mainly manifested as organising pneumonia and fibrosis. The most valuable characteristic is the pleural parallel sign. |
| Wu et al. (2020) [142] | 130 | GGO, GGO with consolidation, parallel pleura sign, paving stone sign, air bronchogram, bronchiectasis, vascular thickening, halo sign, reversed-halo sign, pleural effusion and pneumonocele | GGO and consolidation are the most common CT signs of COVID-19. |
| Bernheim et al. (2020) [143] | 121 | GGOs, GGO with consolidation, consolidation, linear Opacities, rounded morphology of opacities, crazy paving pattern, reverse-halo sign, pleural effusion and underlying pulmonary emphysema | Recognising imaging patterns based on infection time course is paramount for helping to predict patient progression and potential complication development. |
| Zhang et al. (2020) [144] | 120 | GGOs, nodules, linear densities, consolidation, crazy paving, bronchiectasis, effusion, lymphadenopathy, air bronchograms, tree-in-bud sign and white lung | Using chest CT as the primary screening method in epidemic areas is recommended. |
| Hossain et al. (2020) [145] | 119 | GGOs, consolidation, crazy paving, pleural effusions, pleural thickening, bronchiectasis and air trapping | A significant proportion of patients who did not have the respiratory syndrome and underwent non-chest CT scans had evidence of COVID-19 on their CT scans. |
| Zhao et al. (2020) [146] | 118 | GGO, consolidation, centrilobular nodules, architectural distortion, bronchial wall thickening, reticulation, subpleural bands, traction bronchiectasis, vascular enlargement, intrathoracic lymph node enlargement and pleural effusions | The follow-up CT changes during the treatment could help evaluate the treatment response of patients. |
| Wang et al. (2020) [48] | 114 | GGO, consolidation and pleural effusion | Spiral CT can make an early diagnosis and for evaluation of progression, with a diagnostic sensitivity and accuracy better than that of nucleic acid detection. |
| Han et al. (2020) [147] | 108 | GGO, consolidation, GGO with consolidation, vascular thickening, crazy paving pattern, air bronchogram sign and halo sign | |
| Wang et al. (2020) [148] | 13 COVID-19 and 92 non-COVID-19 | GGO, consolidation, GGO with consolidation, air bronchogram and intralobular septal thickening | CT can be used with reasonable accuracy to distinguish influenza from COVID-19. |
| Zhao et al. (2020) [149] | 101 | GGOs, consolidation, mixed GGOs and consolidation, centrilobular nodules, architectural distortion, bronchial wall thickening, reticulation, subpleural bands, traction bronchiectasis, intrathoracic lymph node enlargement, vascular enlargement and pleural effusions | |
| Huang et al. (2020) [150] | 100 | GGO, consolidation, crazy-paving pattern, bronchiectasis, interlobular septal thickening and lymphadenopathy | The mechanism of CT features is explicable based on pathological findings. |
| Zhou et al. (2020) [151] | 100 | GGO, consolidation, GGO with consolidation, thickened interlobular and intralobular septum, crazy-paving, vacuolar sign, microvascular dilation, air bronchogram, subpleural transparent line, thickening of the pleura, pleural retraction, pleural effusion, subpleural line, bronchus distortion, fibrotic strips, lymphadenopathy, pneumothorax and pneumomediastinum | The main CT features of COVID-19 pneumonia mainly included GGO, GGO with consolidation, and GGO with reticular pattern. |
| Li et al. (2020) [152] | 98 | GGO, consolidation, vascular enlargement, interlobular septal thickening, air bronchogram and air trapping | Consolidations on CT images were more common in dead patients than in survival patients. |
| Wang et al. (2020) [153] | 90 | GGO, consolidation, crazy-paving pattern and pleural effusion | The extent of CT abnormalities progressed rapidly after symptom onset, peaked during illness days 6–11, and followed by persistence of high levels. |
| Xu et al. (2020) [154] | 90 | GGO, consolidation, crazy-paving pattern, interlobular septal thickening, linear opacities combined, air bronchogram sign, adjacent pleura thickening, pleural effusion, pericardial effusion and lymphadenopathy | |
| Liang et al. (2020) [155] | 88 | GGO, consolidation, linear opacities, discrete pulmonary nodules and cavitation | |
| Li et al. (2020) [34] | 83 | GGO, linear opacities, consolidation, interlobular septal thickening, crazy-paving pattern, spider web sign, bronchial wall thickening, subpleural curvilinear line, nodule, reticulation, lymph node enlargement, pleural effusion and pericardial effusion | |
| Shi et al. (2020) [52] | 81 | Bilateral, subpleural, GGOs with air bronchograms, ill-defined margins, and a slight predominance in the right lower lobe, irregular interlobular septal thickening, crazy-paving pattern, thickening of the adjacent pleura, nodules, cystic changes, bronchiectasis, pleural effusion, lymphadenopathy, consolidation patterns and reticular patterns | CT findings vary depending on the time interval between the onset of symptoms and the CT performing. |
| Wu et al. (2020) [156] | 80 | GGO, consolidation, interlobular septal thickening, crazy-paving pattern, spider web sign, subpleural line, bronchial wall thickening, lymph node enlargement, pericardial effusion and pleural effusion | |
| Li et al. (2020) [49] | 78 | GGOs, mixed GGOs, consolidation, interlobular septal thickening, air bronchograms, fibrotic lesions and pleural effusion | No centrilobular nodules or lymphadenopathy. |
| Liu et al. (2020) [35] | 73 | Unique GGOs, multiple GGOs, paving stone sign, consolidation, bronchial wall thickening, pleural effusion and thickening of lung texture | The size and CT abnormalities are related to disease severity. |
| Zhu et al. (2020) [57] | 44 younger and 28 older | Pure ground-glass, GGO with consolidation, consolidation, reticular pattern or honeycombing, subpleural line, pleural thickening, pleural traction, pleural effusion, vacuolar sign, air bronchogram and vascular enlargement | Elderly and younger patients with COVID-19 have some similar CT features. However, older patients are more likely to have extensive lung lobe involvement, and subpleural line and pleural thickening. |
| Zhong et al. (2020) [157] | 67 | Solid plaque shadow, halo sign, fibrous strip shadow with ground-glass shadow and consolidation shadow | A solid shadow may predict severe and critical illness. |
| Pan et al. (2020) [42] | 63 | Patchy/punctate GGOs, GGOs, patchy consolidation, fibrous stripes and irregular solid nodules | |
| Zhou et al. (2020) [158] | 62 | GGO, consolidation, GGO with consolidation, nodule, rounded opacities, crazy-paving pattern, air bronchogram, halo sign, subpleural curvilinear line, thoracic lymphadenopathy, pleural effusion or thickening and pulmonary fibrosis | In patients with dyspno and respiratory distress, CT examination is very practical in the preclinical screening of patients with COVID-19. |
| Zhou et al. (2020) [159] | 62 | GGO, consolidation, GGO plus a reticular pattern, vacuolar sign, microvascular dilation sign, fibrotic streaks, subpleural line, subpleural transparent line, air bronchogram, bronchus distortion, thickening of pleura, pleural retraction sign and pleural effusion | GGO and a single lesion at the onset of COVID-19 pneumonia suggested that the disease was in its early phase. Pleural effusion might occur in the advanced phase. |
| Zhang et al. (2020) [160] | 60 | GGO, consolidation, linear opacities, crazy-paving pattern, air bronchogram, emphysema, fibrosis, calcification, pleural effusion and pericardial effusion | This study included critically ill COVID-19 patients with GGO, crazy-paving pattern and air bronchogram as the most common CT findings. |
| Liu et al. (2020) [29] | 59 | Pure GGO, GGO with consolidation, GGO with reticulation, consolidation and pleural effusion | Atypical clinical findings of pregnant women with COVID-19 could increase the difficulty in initial identification. Consolidation was common in the pregnant groups. The chest CT imaging features of children with COVID-19 pneumonia were non-specific. At the same time, the exposure history and clinical symptoms could be more helpful for the screening. |
| Meng et al. (2020) [161] | 58 | GGO with peripheral distribution and unilateral location, fine reticulation, subpleural curvilinear line, halo sign, air bronchogram, vascular enlargement and consolidation | CT scan has great value in the highly suspicious, asymptomatic cases with negative nucleic acid testing. |
| Lomoro et al. (2020) [66] | 58 | GGO, GGO with consolidation, crazy-paving patterns, fibrous stripes, subpleural lines, architectural distortion, air bronchogram sign, perilesional vascular thickening, scattered nodules, enlarged mediastinal lymph nodes and pleural effusion | |
| Fu et al. (2020) [162] | 56 | GGO, GGO with consolidation, consolidation, thickened small vessels within opacity, air bronchograms, interlobular septal thickening and crazy-paving pattern | CT plays a crucial role in early diagnosis and assessment of COVID-19 pneumonia progression. |
| Li and Xia(2020) [163] | 53 | GGOs and consolidation with or without vascular enlargement, interlobular septal thickening and air bronchogram sign | Low rate of misdiagnosis of COVID-19 in CT images. |
| Guan et al. (2020) [46] | 53 | GGO, crazy paving, consolidation, stripe, air bronchogram, pulmonary nodules and secondary tuberculosis | Identification of CT features of COVID-19 pneumonia provides timely diagnostic evidence. |
| Wang et al. (2020) [164] | 52 | GGOs, patchy consolidation and sub-consolidation, air bronchi sign, thickened leaflet interval and fibrous stripes | The chest CT images of patients with COVID-19 have specific characteristics with dynamic changes, which are of value for monitoring disease progress and clinical treatment. |
| Lin et al. (2021) [165] | 52 | GGO, consolidation, GGO with consolidation, mosaic attenuation, bronchial wall thickening, Centrilobular nodules, interlobular septal thickening, crazy paving pattern, air bronchogram and mucoid impaction | Most lesions in patients with COVID-19 pneumonia were located in the peripheral zone and close to the pleura, whereas influenza virus pneumonia was more prone to show mucoid impaction and pleural effusion. |
| Lyu et al. (2020) [36] | 51 | Consolidation, crazy-paving pattern and air bronchogram | Severity assessment of COVID-19 pneumonia based on chest CT would be feasible for critical cases. |
| Fang et al. (2020) [166] | 51 | GGOs, GGO with consolidation, consolidation and linear opacity | The sensitivity of CT for COVID-19 infection is 98% compared to RT-PCR sensitivity of 71%. |
| Xu et al. (2020) [167] | 50 | GGO, mixed GGOs and consolidation, consolidation, thickened intralobular septa, thickened interlobular septa, air bronchogram, pleural effusion and enlarged mediastinal nodes | Repeated CT scanning helps monitor disease progression and implement timely treatment. |
| Lei et al. (2020) [168] | 49 | GGOs, interstitial thickening, and consolidation, fibrosis, parenchymal band, traction bronchiectasis and irregular interfaces | |
| Yang et al. (2020) [169] | 44 | Pure GGOs, GGO with consolidation, GGO with interlobular septal thickening, consolidation, vessel expansion, air bronchogram, mediastinal lymphadenectasis and pleural effusion | The features of early-stage COVID-19 include GGO-based lesions with rare small size consolidation mainly distributed in the peripheral and posterior part of the lung. |
| Xiong et al. (2020) [43] | 42 | Single or multiple GGO, consolidation, interstitial thickening or reticulation, air bronchograms, pleural effusion and fibrous strips | |
| Long et al. (2020) [170]57 | 36 | GGOs, GGO with consolidation, lymphadenopathy and pleural effusion | Patients with typical CT findings but negative RRT-PCR results should be isolated. |
| Chen et al. (2020) [171] | 34 | Pure GGO, GGO with reticular and/or interlobular septal thickening, GGO with consolidation, pleural effusion, pleural thickening and pericardial effusion | Chest CT is crucial for the early diagnosis of COVID-19, particularly for those patients with a negative RT-PCR. |
| Liu et al. (2020) [172] | 33 | Subpleural lesions, central lesions, ground-glass density shadow, consolidation, interstitial change and interlobular septal thickening | An important basis of CT images for early detection and disease monitoring. |
| Cheng et al. (2020) [173] | 11 COVID-19 and 22 non-COVID-19 | GGO, mixed GGO, consolidation, air bronchogram, centrilobular nodules, tree-in-bud sign, reticular pattern, subpleural linear opacity, bronchial dilatation and cystic change | findings of more extensive GGO than consolidation on chest CT scans obtained during the first week of illness were considered findings highly suspicious of COVID-19. |
| Zhou et al. (2020) [174] | 29 | GGO, GGO with consolidation, consolidation, interlobular septa thickening, parenchymal bands, air bronchogram, pleural thickening, architectural distortion and pleural effusion | Chest CT reflects the development of COVID-19 pneumonia. |
| Yuan et al. (2020) [175] | 27 | GGO, consolidation, GGO with consolidation, air bronchogram, Nodular opacities and pleural effusion | A simple CT scoring method was capable of predicting mortality. |
| Dane et al. (2020) [176] | 23 | GGO, ground-glass nodule, solid nodule, consolidation, halo sign and interstitial thickening | |
| Wu et al. (2020) [45] | 23 | GGO, patchy, wedge-shaped ground-glass shadows, intralobular interstitial thickening with consolidation, fibrous stripes and concomitant hydropericardium and/or hydrothorax | Radiological findings and clinical characteristics in pregnant women with COVID-19 were similar to those of non-pregnant women with COVID-19. |
| Himoto et al. (2020) [177] | 21 | Bilateral GGO, peripheral-predominant lesions without airway abnormalities, mediastinal lymphadenopathy and pleural effusion | Important supplemental role of CT imaging to triage and detect patients suspected COVID-19 pneumonia, before getting the results of RT-PCR. |
| Chung et al. (2020) [178] | 21 | GGOs, GGO with consolidation, consolidation, rounded morphology, linear opacities and crazy-paving pattern | |
| Pan et al. (2020) [179] | 21 | GGOs, crazy-paving pattern, inter- and intralobular septal thickening and consolidation | Chest CT signs of improvement began at approximately 14 days after the onset of initial symptoms. |
| Chen et al. (2021) [180] | 21 | GGO, consolidation with a subpleural distribution, air bronchogram, vascular enlargement, interlobular septal thickening and pleural effusions | Chest CT is important in the screening of patients in whom disease is clinically suspected, especially those who have negative initial RT-PCR results. |
| Xia et al. (2020) [54] | 20 | Consolidation with surrounding halo sign, GGOs, fine mesh shadow, tiny nodules, interlobular septal thickening, fibrosis lesions, air bronchogram signs and pleural thickening | Procalcitonin elevation and consolidation with surrounding halo signs were frequent in paediatric patients. |
| Zhu et al. (2020) [181] | 7 patients with Heart failure and 12 with COVID-19 | GGO and thickening of the interlobular septum in both group. In heart failure group, the ratio of the expansion of small pulmonary veins was also higher. | There are significant differences in chest CT features, such as enlargement of pulmonary veins, lesions distribution and morphology between heart failure and COVID-19. |
| Han et al. (2020) [47] | 17 | GGO, GGO with interlobular septal thickening, GGO with irregular linear opacities, consolidation, presence of nodule, enlarged pulmonary vessels, bronchiolar dilatation, crazy paving, air bronchogram, thickening of the adjacent pleura, interleaf fissure displacement, evidence of pulmonary fibrosis and pleural effusion | There is a synchronised improvement in both clinical and radiologic features in the 4th week. |
| Feng et al. (2020) [58] | 15 | Small nodular GGOs and speckled GGOs | Dynamic reexamination of chest CT and nucleic acid are essential in children. |
| Lei et al. (2020) [182] | 14 | Presence of nodular, GGO, bronchovascular enlarged, irregular linear appearances, consolidation pulmonary opacity and pleural effusion | |
| Zhu et al. (2020) [183] | 14 | GGOs, mixed GGO and consolidation, reticulation, crazy paving, cavitation and bronchiectasis | There is a need to develop a new detection technique. |
| Chate et al. (2020) [184] | 12 | GGOs, crazy-paving pattern, alveolar consolidation, reversed-halo sign and pleural effusion | |
| Agostini et al. (2020) [44] | 10 | GGOs, GGO with consolidation, linear opacities, rounded opacities, crazy-paving pattern, reverse-halo sign, bronchial wall thickening and bronchiectasis | Ultra-low-dose, dual-source, fast CT protocol provides highly diagnostic images for COVID-19 with potential for reduction in dose and motion artefacts. |
| Zhou et al. (2020) [55] | 9 | Nodular lesions, patchy lesions, GGO with consolidation and halo sign | Infants and young children with COVID-19 have mild clinical symptoms and imaging findings not as typical as those of adults. |
| Yoon et al. (2020) [68] | 9 | Pure GGO, mixed GGO and consolidation, consolidation, crazy-paving appearance and air bronchogram | |
| Iwasawa et al. (2020) [40] | 6 | GGOs, consolidation, linear opacities, reticulation and crazy-paving pattern | U-HRCT can evaluate not only the distribution and hallmarks of COVID-19 pneumonia but also visualise local lung volume loss. |
| Gao and Zhang (2020) [39] | 6 | GGOs, nodule, halo sign, thickened lobular septum, thickened bronchial wall, tree-in-bud sign, crazy-paving sign, proliferation and calcification | The imaging manifestations of early-stage COVID-19 are relatively mild, and the imaging findings of some patients are not typical, which can easily lead to missed diagnoses. |
| Zhu et al. (2020) [185] | 6 | GGO, GGO with consolidation, consolidation, reticulation, crazy paving and bronchiectasis | In the early-stage of the disease, the lesion can manifest as round nodular-like GGO in the central area of the lung lobe. The follow-up CT images showed the lesions are migratory manifested as the absorption of the primary lesions and the emergence of new lesions. |
| Li et al. (2020) [56] | 5 | Patchy GGOs | Similar but more modest lung abnormalities at CT of children compared to adults |
| Liu et al. (2020) [41] | 5 | GGOs with consolidation | The paediatric patients generally have milder CT findings than adults. |
| Lu and Pu (2020) [186] | 5 | Crazy-paving pattern, GGOs, septal line thickening, consolidation and thickened interlobular septa | |
| Xie et al. (2020) [187] | 5 | Multifocal GGO, parenchyma consolidation, mixed GGO and mixed consolidation |