Coronavirus Disease 2019 (COVID-19) Pneumonia Presentations in Chest Computed Tomography: A Pictorial Review

Despite imaging not being a tool for novel coronavirus disease 2019 (COVID-19) diagnosis, there has been an increased number of chest computed tomography (CT) scans done worldwide. There are no pathognomonic CT features for COVID-19 pneumonia, as findings are also common in other infectious diseases and noninfectious aetiologies. Nonetheless, point-of-care physicians should be familiarized with the most common imaging presentations of the COVID-19. In this pictorial review, we have summarized the most reported imaging features of COVID-19 pneumonia, including possible differential diagnosis according to the CT finding.     

人工智能肺炎诊断系统在新型冠状病毒肺炎疫情期间胸部CT检查中的应用

目的 分析新型冠状病毒肺炎疫情期间人工智能(AI)在胸部CT诊断检查中的效能.方法 选取2020年2月至4月间行胸部CT扫描的受检者5 000例,分别通过AI和2名资深胸部影像诊断医师进行分析检测.结果 5 000例患者中,真阳性共1 084例,诊断正确率、错误率、灵敏度分别是72％、27％、47％.结论 AI在肺炎C...     

Structured reporting of chest CT provides high sensitivity and specificity for early diagnosis of COVID-19 in a clinical routine setting

Objectives:Although chest CT has been widely used in patients with COVID-19, its role for early diagnosis of COVID-19 is unclear. We report the diagnostic performance of chest CT using structured reporting in a routine clinical setting during the early phase of the epidemic in Germany.Methods:Patients with clinical suspicion of COVID-19 and moderate-to-severe symptoms were included in this retrospective study. CTs were performed and reported before RT-PCR results (reference standard) became available. A structured reporting system was used that concluded in a recently described five-grade score (“CO-RADS”), indicating the level of suspicion for pulmonary involvement of COVID-19 from 1 = very low to 5 = very high. Structured reporting was performed by three Radiologists in consensus.Results:In 96 consecutive patients (50 male, mean age 64), RT-PCR was positive in 20 (21%) cases. CT features significantly more common in RT-PCR-positive patients were ground-glass opacities as dominant feature, crazy paving, hazy margins of opacities, and multifocal bilateral distribution (p < 0.05). Using a cut-off point between CO-RADS 3 and 4, sensitivity was 90%, specificity 91%, positive predictive value 72%, negative predictive value 97%, and accuracy 91%. ROC analysis showed an AUC of 0.938.Conclusions:Structured reporting of chest CT with a five-grade scale provided accurate diagnosis of COVID-19. Its use was feasible and helpful in clinical routine.Advances in knowledge:Chest CT with structured reporting may be a provisional diagnostic alternative to RT-PCR testing for early diagnosis of COVID-19, especially when RT-PCR results are delayed or test capacities are limited.     

Role of complementary Ct chest in patients presenting with acute abdominal symptoms during covid-19 pandemic: a UK experience

BackgroundIn March 2020, the UK Intercollegiate General Surgery Guidance on COVID-19 recommended that patients undergoing emergency abdominal CT should have a complementary CT chest for COVID-19 screening.PurposeTo establish if complementary CT chest was performed as recommended, and if CT chest influenced surgical intervention decision. To assess detection rate of COVID-19 on CT and its correlation with RT-PCR swab results. To determine if COVID-19 changes is reliably detected within the lung bases which are usually imaged in standard abdominal CT.MethodsPatients with acute abdominal symptoms presenting to a single institution between 1st and 30th April 2020 who had abdominal CT and complementary CT chest were retrospectively extracted from Computerised Radiology Information System. CT COVID-19 changes were categorised according to British Society of Thoracic Radiology reporting guidance. Patient demographics (age and gender), RT-PCR swab results and management pathway (conservative or intervention) were recorded from electronic patient records. Statistical analyses were performed to evaluate any significant association between variables. p values ≤0.05 were regarded as statistically significant.ResultsCompliancy rate in performing complementary CT chest was 92.5% (148/160). Thirty-five patients (35/148,23.6%) underwent intervention during admission. There was no significant association (p = 0.9085) between acquisition of CT chest and management pathway (conservative vs intervention). CT chest had 57% sensitivity (CI 18.41% to 90.1%) and 100% specificity (CI 92% to 100%) in COVID-19 diagnosis. Three of ten patients who had classic COVID-19 changes on CT chest did not have corresponding changes in lung bases.ConclusionCompliance with performing complementary CT chest in acute abdomen patients for COVID-19 screening was high and it did not influence subsequent surgical or interventional management.     

Differential diagnosis between the coronavirus disease 2019 and Streptococcus pneumoniae pneumonia by thin-slice CT features

ObjectiveThe chest computed tomography (CT) features of coronavirus disease 2019 (COVID-19) and Streptococcus pneumoniae pneumonia (S. pneumoniae pneumonia) were compared to provide further evidence for the differential imaging diagnosis of patients with these two types of pneumonia.MethodsClinical information and chest CT data of 149 COVID-19 patients between January 9, 2020 and March 15, 2020 and 97 patients with S. pneumoniae pneumonia between January 23, 2011 and March 18, 2020 in Zhongnan Hospital of Wuhan University were retrospectively analyzed. In addition, CT features were comparatively analyzed.ResultsAccording to the chest CT images, the probability of lung segmental and lobar pneumonia in S. pneumoniae pneumonia was higher than that in COVID-19(P<0.001); the probabilities of ground-glass opacity (GGO), the “crazy paving” sign, and abnormally thickened interlobular septa in COVID-19 were higher than those in S. pneumoniae pneumonia(P = 0.005, P<0.001, P<0.001, respectively); and the probabilities of consolidation lesions, bronchial wall thickening, centrilobular nodules, and pleural effusion in S. pneumoniae pneumonia were higher than those in COVID-19 (P<0.001, P = 0.001, P = 0.003, P = 0.001, respectively).ConclusionThe findings of GGO, the crazy paving sign, and abnormally thickened interlobular septa on chest CT were significantly higher in COVID-19 than S. pneumoniae pneumonia. The most important differential points on chest CT signs between COVID-19 and S. pneumoniae pneumonia were whether disease lesions were distributed in entire lung lobes and segments and whether the crazy paving sign, interlobular septal thickening, and consolidation lesions were found.     

Diagnostic accuracy of CT and radiographic findings for novel coronavirus 2019 pneumonia: Systematic review and meta-analysis

PurposeTo evaluate pooled prevalence, sensitivity, and specificity of chest computed tomography (CT) and radiographic findings for novel coronavirus-2019 (COVID-19) pneumonia.MethodsWe performed systematic literature search in PubMed and Embase to identify articles reporting baseline imaging findings of COVID-19 pneumonia. The quality of the articles was assessed using NIH quality assessment tool for case series studies. The pooled prevalence, sensitivity, specificity, and diagnostic odds ratio of imaging findings were calculated.ResultsFifty-six studies (6007 patients, age, 2.1–70 years, 2887 females, 5762 CT, 396 radiographs,) were included. The mean interval between onset of symptoms and CT acquisition was 1–8 days. On CT, the pooled prevalence of ground glass opacities (GGO), GGO plus consolidation, and consolidation only was 66.9% (95% CI 60.8–72.4%), 44.9% (38.7–51.3%), and 32.1 (23.6–41.9%) respectively. Pooled sensitivity and specificity of GGO on CT was 73% (71%–80%) and 61% (41%–78%), respectively. For GGO plus consolidation and consolidation only, the pooled sensitivities/ specificities were 58% (48%–68%)/ 58% (41%–73%) and 49% (20%–78%)/ 56% (30%–78%), respectively. The pooled prevalence of GGO and consolidation on chest radiograph was 38.7% (22.2%–58.3%) and 46.9% (29.7%–64.9%), respectively. The diagnostic accuracy of radiographic findings could not be assessed due to small number of studies.ConclusionGGO on CT has the highest diagnostic performance for COVID-19 pneumonia, followed by GGO plus consolidation and consolidation only. However, the moderate to low sensitivity and specificity suggest that CT should not be used as the primary tool for diagnosis. Chest radiographic abnormalities are seen in half of the patients.     

CT-based radiomics for predicting the rapid progression of coronavirus disease 2019 (COVID-19) pneumonia lesions

Objectives:To develop and validate a radiomic model to predict the rapid progression (defined as volume growth of pneumonia lesions > 50% within seven days) in patients with coronavirus disease 2019 (COVID-19).Methods:Patients with laboratory-confirmed COVID-19 who underwent longitudinal chest CT between January 01 and February 18, 2020 were included. A total of 1316 radiomic features were extracted from the lung parenchyma window for each CT. The least absolute shrinkage and selection operator (LASSO), Relief, Las Vegas Wrapper (LVW), L1-norm-Support Vector Machine (L1-norm-SVM), and recursive feature elimination (RFE) were applied to select the features that associated with rapid progression. Four machine learning classifiers were used for modeling, including Support Vector Machine (SVM), Random Forest (RF), Logistic Regression (LR), and Decision Tree (DT). Accordingly, 20 radiomic models were developed on the basis of 296 CT scans and validated in 74 CT scans. Model performance was determined by the receiver operating characteristic curve.Results:A total of 107 patients (median age, 49.0 years, interquartile range, 35–54) were evaluated. The patients underwent a total of 370 chest CT scans with a median interval of 4 days (interquartile range, 3–5 days). The combination methods of L1-norm SVM and SVM with 17 radiomic features yielded the highest performance in predicting the likelihood of rapid progression of pneumonia lesions on next CT scan, with an AUC of 0.857 (95% CI: 0.766–0.947), sensitivity of 87.5%, and specificity of 70.7%.Conclusions:Our radiomic model based on longitudinal chest CT data could predict the rapid progression of pneumonia lesions, which may facilitate the CT follow-up intervals and reduce the radiation.Advances in knowledge:Radiomic features extracted from the current chest CT have potential in predicting the likelihood of rapid progression of pneumonia lesions on the next chest CT, which would improve clinical decision-making regarding timely treatment.     

Hallazgos tomográficos entre sobrevivientes y no-sobrevivientes con COVID-19 y utilidad clínica de una puntuación de tomografía torácica

BackgroundMany patients with coronavirus disease 2019 (COVID-19) have been diagnosed with computed tomography (CT). A prognostic tool based on CT findings could be useful for predicting death from COVID-19.ObjectivesTo compare the chest CT findings of patients who survived COVID-19 versus those of patients who died of COVID-19 and to determine the usefulness the clinical usefulness of a CT scoring system for COVID-19.MethodsWe included 124 patients with confirmed SARS-CoV-2 infections who were hospitalized between April 1, 2020 and July 25, 2020.ResultsWhereas ground-glass opacities were the most common characteristic finding in survivors (75%), crazy paving was the most characteristic finding in non-survivors (65%). Atypical findings were present in 46% of patients. The chest CT score was directly proportional to mortality; a score ≥ 18 was the best cutoff for predicting death, yielding 70% sensitivity (95%CI: 47%-87%).ConclusionsOur results suggest that atypical lesions are more prevalent in this cohort. The chest CT score had high sensitivity for predicting hospital mortality     

Comparación de los hallazgos en la tomografía computarizada de pacientes adultos y pediátricos con COVID-19

ObjectiveInitial COVID-19 reports described a variety of clinical presentations, but lower respiratory abnormalities are most common and chest CT findings differ between adult and pediatric patients. We aim to summarize early CT findings to inform healthcare providers on the frequency of COVID-19 manifestations specific to adult or pediatric patients, and to determine if the sensitivity of CT justifies its use in these populations.MethodsPubMed was searched for the presence of the words “CT, imaging, COVID-19” in the title or abstract, and 17 large-scale PubMed and/or Scopus studies and case reports published between January 1, 2020 and April 15, 2020 were selected for data synthesis.ResultsInitial CT scans identified ground-glass opacities and bilateral abnormalities as more frequent in adults (74%, n = 698, and 89%, n = 378, respectively) than children (60%, n = 25, and 37%, n = 46). At 14+ days, CT scans evidenced varied degrees of improvement in adults but no resolution until at least 26 days after the onset of flu-like symptoms. In pediatric patients, a third (n = 9) showed additional small nodular GGOs limited to a single lobe 3-5 days after an initial CT scan.ConclusiónEarly adult CT findings suggest the limited use of CT as a supplemental tool in diagnosing COVID-19 in symptomatic adult patients, with a particular focus on identifying right and left lower lobe abnormalities, GGOs, and interlobular septal thickening. Early pediatric CT findings suggest against the use of CT if RT-PCR is available given its significantly lower sensitivity in this population and radiation exposure.     

Magnetic resonance imaging features of coronavirus disease 2019 (COVID-19) pneumonia: The first preliminary case series

Rationale and objectivesThere is a rising onus on understanding the common features of COVID-19 pneumonia on different imaging modalities. In this study, we aimed to review and depict the common MRI features of COVID-19 pneumonia in our laboratory confirmed case series, the first comprehensive reported cohort in the literature.Materials and methodsUpon IRB approval, eight laboratory confirmed COVID-19 patients who presented to our outpatient imaging clinic underwent chest CT and, once various features of COVID-19 pneumonia were identified, a dedicated multisequence chest MRI was performed on the same day with an institutional protocol. Demographic data and the morphology, laterality and location of the lesions were recorded for each case.ResultsFive males and three females with the mean age of 40.63 ± 12.64 years old were present in this case series. Five cases had typical CT features with ground glass opacities and consolidations, readily visible on different MRI sequences. Three cases had indeterminate or atypical features which were also easily seen on MRI. The comprehensive review of MRI features for each case and representative images have been illustrated.ConclusionBecoming familiar with typical findings of COVID-19 pneumonia in MRI is crucial for every radiologist. Although MRI is not the modality of choice for evaluation of pulmonary opacities, it has similar capabilities in detection of COVID-19 pneumonia when compared to chest CT.