Organizing Pneumonia of COVID-19: Time-dependent Evolution and Outcome in CT Findings

AbstractObjectiveAs a pandemic, a most-common pattern resembled organizing pneumonia (OP) has been identified by CT findings in novel coronavirus disease (COVID-19). We aimed to delineate the evolution of CT findings and outcome in OP of COVID-19.Materials and Methods106 COVID-19 patients with OP based on CT findings were retrospectively included and categorized into non-severe (mild/common) and severe (severe/critical) groups. CT features including lobar distribution, presence of ground glass opacities (GGO), consolidation, linear opacities and total severity CT score were evaluated at three time intervals from symptom-onset to CT scan (day 0-7, day 8-14, day>14). Discharge or adverse outcome (admission to ICU or death), and pulmonary sequelae (complete absorption or lesion residuals) on CT after discharge were analyzed based on the CT features at different time interval.Results79(74.5%) patients were non-severe and 103(97.2%) were discharged at median day 25 (range, day 8-50) after symptom-onset. Of 67 patients with revisit CT at 2-4 weeks after discharge, 20(29.9%) had complete absorption of lesions at median day 38 (range, day 30-53) after symptom-onset. Significant differences between complete absorption and residuals groups were found in percentages of consolidation (1.5% vs. 13.8%, P=0.010), number of involved lobe >3 (40.0% vs. 72.5%, P=0.030), CT score >4 (20.0% vs. 65.0%, P=0.010) at day 8-14.ConclusionsMost OP cases had good prognosis. Approximately one-third of cases had complete absorption of lesions during 1-2 months after symptom-onset while those with increased frequency of consolidation, number of involved lobe>3, and CT score >4 at week 2 after symptom-onset may indicate lesion residuals on CT.

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Organizing pneumonia of COVID-19: Time-dependent evolution and outcome in CT findings

PLoS ONE ◽

10.1371/journal.pone.0240347 ◽

2020 ◽

Vol 15 (11) ◽

pp. e0240347

Author(s):

Yan Wang ◽

Chao Jin ◽

Carol C. Wu ◽

Huifang Zhao ◽

Ting Liang ◽

...

Keyword(s):

Symptom Onset ◽

Good Prognosis ◽

Critical Groups ◽

Time Interval ◽

Organizing Pneumonia ◽

Time Intervals ◽

Ct Findings ◽

Complete Absorption ◽

Novel Coronavirus ◽

Ct Features

Background As a pandemic, a most-common pattern resembled organizing pneumonia (OP) has been identified by CT findings in novel coronavirus disease (COVID-19). We aimed to delineate the evolution of CT findings and outcome in OP of COVID-19. Materials and methods 106 COVID-19 patients with OP based on CT findings were retrospectively included and categorized into non-severe (mild/common) and severe (severe/critical) groups. CT features including lobar distribution, presence of ground glass opacities (GGO), consolidation, linear opacities and total severity CT score were evaluated at three time intervals from symptom-onset to CT scan (day 0–7, day 8–14, day > 14). Discharge or adverse outcome (admission to ICU or death), and pulmonary sequelae (complete absorption or lesion residuals) on CT after discharge were analyzed based on the CT features at different time interval. Results 79 (74.5%) patients were non-severe and 103 (97.2%) were discharged at median day 25 (range, day 8–50) after symptom-onset. Of 67 patients with revisit CT at 2–4 weeks after discharge, 20 (29.9%) had complete absorption of lesions at median day 38 (range, day 30–53) after symptom-onset. Significant differences between complete absorption and residuals groups were found in percentages of consolidation (1.5% vs. 13.8%, P = 0.010), number of involved lobe > 3 (40.0% vs. 72.5%, P = 0.030), CT score > 4 (20.0% vs. 65.0%, P = 0.010) at day 8–14. Conclusion Most OP cases had good prognosis. Approximately one-third of cases had complete absorption of lesions during 1–2 months after symptom-onset while those with increased frequency of consolidation, number of involved lobe > 3, and CT score > 4 at week 2 after symptom-onset may indicate lesion residuals on CT.

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A pattern categorization of CT findings to predict outcome of COVID-19 pneumonia

10.1101/2020.05.19.20107409 ◽

2020 ◽

Author(s):

Chao Jin ◽

Yan Wang ◽

Carol C. Wu ◽

Huifang Zhao ◽

Ting Liang ◽

...

Keyword(s):

Mechanical Ventilation ◽

Symptom Onset ◽

Diffuse Alveolar Damage ◽

Clinical Findings ◽

Adverse Outcomes ◽

Organizing Pneumonia ◽

Reactive Protein ◽

Ct Findings ◽

Complete Absorption ◽

Novel Coronavirus

AbstractsPurposeAs global healthcare system is overwhelmed by novel coronavirus disease (COVID-19), early identification of risks of adverse outcomes becomes the key to optimize management and improve survival. This study aimed to provide a CT-based pattern categorization to predict outcome of COVID-19 pneumonia.Methods165 patients with COVID-19 (91 men, 4-89 years) underwent chest CT were retrospectively enrolled. CT findings were categorized as Pattern0 (negative), Pattern1 (bronchopneumonia), Pattern2 (organizing pneumonia), Pattern3 (progressive organizing pneumonia) and Pattern4 (diffuse alveolar damage). Clinical findings were compared across different categories. Time-dependent progression of CT patterns and correlations with clinical outcomes, i.e. discharge or adverse outcome (admission to ICU, requiring mechanical ventilation, or death), with pulmonary sequelae (complete absorption or residuals) on CT after discharge were analyzed.ResultsOf 94 patients with outcome, 81(86.2%) were discharged, 3(3.2%) were admitted to ICU, 4(4.3%) required mechanical ventilation, 6(6.4%) died. 31(38.3%) had complete absorption at median day 37 after symptom-onset. Significant differences between pattern-categories were found in age, disease-severity, comorbidity and laboratory results (all P<0.05). Remarkable evolution was observed in Pattern0-2 and Pattern3-4 within 3 and 2 weeks after symptom-onset, respectively; most of patterns remained thereafter. After controlling for age, CT pattern significantly correlated with adverse outcomes (Pattern4 vs. Pattern0-3 [reference]; hazard-ratio[95%CI], 18.90[1.91-186.60], P=0.012). CT pattern (Pattern3-4 vs. Pattern0-2 [reference]; 0.26[0.08-0.88], P=0.030) and C-reactive protein (>10 vs. ≤10mg/L [reference]; 0.31[0.13-0.72], P=0.006) were risk-factors associated with pulmonary residuals.ConclusionCT pattern categorization allied with clinical characteristics within 2 weeks after symptom-onset would facilitate early prognostic stratification in COVID-19 pneumonia.

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Evolution of CT patterns in novel coronavirus (2019-nCoV) pneumonia in relation to clinical and laboratory data

Diagnostic radiology and radiotherapy ◽

10.22328/2079-5343-2021-12-2-49-58 ◽

2021 ◽

Vol 12 (2) ◽

pp. 49-58

Author(s):

А. А. Oganesyan ◽

I. V. Shrainer ◽

V. N. Vinogradov ◽

E. S. Pershina ◽

E. G. Koshelev ◽

...

Keyword(s):

Prognostic Value ◽

Patient Management ◽

Dynamic Change ◽

Laboratory Data ◽

Good Prognosis ◽

Organizing Pneumonia ◽

C Reactive Protein ◽

Reactive Protein ◽

Novel Coronavirus ◽

Ct Studies

Introduction. The CT patterns of coronavirus pneumonia are clear and represent certain pathomorphosis at the period of coronavirus pandemic. However, there are a lot of questions about influence of CT-patterns and their dynamic change on a disease’s severity. The aim of the study. To evaluate the dynamics of pulmonary CT changes of novel coronavirus (2019-nCoV) pneumonia in relation to clinical and laboratory data. Materials and methods. CT studies in dynamics of 108 patients with a of novel coronavirus (2019-nCoV) pneumonia were analyzed. The first CT study was performed on admission (6,7±4,1 days of the disease), the first control CT on 11,1±4,9 days of the disease, and the second CT control was performed on 16,7±5,6 days of the disease. Results. The volume of the lesion and the predominant CT symptom at admission did not affect the prognosis. However, changes in the repeated CT study had a high prognostic value. Thus, the occurrence of a pattern of organizing pneumonia during repeated study is associated with a good prognosis, while an increase in the zones of «crazy paving» and a larger volume of damage are unfavorable prognostic signs. An increase in the volume of changes in the type of ground glass and «crazy paving» correlated with increased levels of C-reactive protein, lactate dehydrogenase, and lymphopenia. Conclusion. Data from CT studies in dynamics for novel coronavirus (2019-nCoV) pneumonia have a prognostic value and, in combination with clinical and laboratory data, can influence decision-making on patient management.

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Early Computed Tomography Findings of Novel Coronavirus Disease 2019 (COVID-19) Pneumonia

Archives of Clinical Infectious Diseases ◽

10.5812/archcid.106868 ◽

2020 ◽

Vol 15 (5) ◽

Author(s):

Pinar Diydem Yilmaz ◽

Cengiz Kadiyoran ◽

Suleyman Bakdik ◽

Necdet Poyraz ◽

Hulya Vatansev

Keyword(s):

Computed Tomography ◽

Retrospective Study ◽

Imaging Modality ◽

Ground Glass Opacity ◽

Ground Glass ◽

Pleural Thickening ◽

Halo Sign ◽

Ct Findings ◽

Novel Coronavirus ◽

Ct Features

Background: Novel coronavirus disease (COVID-19) pneumonia is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is highly contagious and threatens human health. Chest computed tomography (CT) is an accurate imaging modality for diagnosis and follow-up. Objectives: To investigate early CT features of COVID-19 pneumonia. Methods: Retrospective study. Sixty-three patients with COVID-19 pneumonia (28 men, 35 women; age range, 21 - 85 years; mean, 59 years) confirmed by reverse transcription-polymerase chain reaction (RT-PCR) were enrolled in this retrospective study and CT findings were evaluated. Patients were classified into three groups for estimating COVID-19 pneumonia, according to CT features. Results: Nineteen (30%) patients classified as out of COVID-19 pneumonia had normal CT findings. Twenty-eight (44%) patients, classified as highly suggestive for COVID-19 pneumonia, had typical findings for COVID-19 pneumonia. In highly suggestive for COVID-19 pneumonia group most common CT features were peripheral (64%), multilobar (96%), patchy, and round (54%) ground-glass opacity (GGO) (57%). Air bronchogram (93%), crazy-paving patterns (79%), and vascular thickening (61%) were the most common special findings. We only detected these rare findings such as halo sign, reverse halo sign, lymphadenopathy, pleural and pericardial effusion, pleural thickening, and fibrotic lines in patients with COVID-19 with chronic diseases. Conclusions: The early CT findings are peripheral, multilobar, patchy, and round ground glass opacities accompanied by vascular thickening, crazy-paving pattern, or air bronchogram sign. Rare findings are only seen in the presence of concomitant diseases.

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Comparison of Outcomes after Reperfusion Therapy between In-Hospital and Out-of-Hospital Stroke Patients

Cerebrovascular Diseases ◽

10.1159/000381787 ◽

2015 ◽

Vol 40 (1-2) ◽

pp. 28-34 ◽

Cited By ~ 4

Author(s):

Joonsang Yoo ◽

Dongbeom Song ◽

Kijeong Lee ◽

Young Dae Kim ◽

Hyo Suk Nam ◽

...

Keyword(s):

Hospital Mortality ◽

Symptom Onset ◽

Reperfusion Therapy ◽

University Hospital ◽

Time Interval ◽

Time Intervals ◽

Symptomatic Intracerebral Hemorrhage ◽

All Cause Mortality ◽

Tissue Plasminogen ◽

Favorable Functional Outcome

Background: Patients may experience stroke while being admitted to the hospital (in-hospital stroke (IHS)) and they may be important candidates for reperfusion therapy. IHS patients may have various comorbidities and show worse outcomes compared with patients with an out-of-hospital stroke (OHS). On the other hand, the time from onset to treatment may be shorter in IHS patients than OHS patients. Most outcome studies of reperfusion therapy have been based on findings in OHS patients, and little information is currently available regarding outcomes of IHS, whether the outcomes differ between patients with IHS and those with OHS who receive reperfusion therapy. Methods: This is a retrospective observational study using prospectively registered data. Consecutive patients who underwent the reperfusion therapy (intravenous (IV), intra-arterial (IA), or combined IV and IA) between July 2002 and June 2014 in a university hospital were included for this study. We compared the demographics, time interval from symptom onset to treatment, and outcomes between IHS and OHS patients and analyzed the factors associated with in-hospital mortality. Results: A total of 686 patients received the reperfusion therapy during the study period. Of them, 256 (37.3%) patients received the IV tissue plasminogen activator (t-PA) therapy only, 243 (35.4%) patients received the IA therapy only, and 187 (27.3%) patients received the combined IV and IA therapy. Among these, 104 (15.2%) were IHS patients. The time intervals from symptom onset to IV t-PA administration (87.5 ± 48.4 vs. 113.4 ± 38.3 min, p < 0.001) and IA puncture (221.8 ± 195.0 vs. 343.6 ± 155.4 min, p < 0.001) were shorter for IHS than OHS. The rates of successful recanalization and symptomatic intracerebral hemorrhage, and the favorable functional outcome at 3 months were similar between the groups. In-hospital all-cause mortality was higher in IHS than OHS (16.3 vs. 8.4%, p = 0.019), but after adjustment, IHS was not an independent factor. The stroke mortality did not differ between the groups (9.6 vs. 6.9%, p = 0.432). Conclusions: Although IHS patients more frequently had comorbid diseases and higher overall in-hospital mortality, the standard outcomes of the reperfusion therapy were similar between IHS and OHS patients, which might be, in part, ascribed to the shorter interval from symptom onset to treatment in IHS. Considering a substantial portion of IHS patients, we should pay more attention to these patients.

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Crescentic and Ring-Shaped Opacities

Acta Radiologica ◽

10.1177/02841851960373p289 ◽

1996 ◽

Vol 37 (3P2) ◽

pp. 889-892 ◽

Cited By ~ 21

Author(s):

A. E. Voloudaki ◽

D. E. Bouros ◽

M. E. Froudarakis ◽

G. E. Datseris ◽

E. G. Apostolaki ◽

...

Keyword(s):

Broad Spectrum ◽

Bronchiolitis Obliterans ◽

Organizing Pneumonia ◽

Bronchiolitis Obliterans Organizing Pneumonia ◽

Pathologic Correlation ◽

Ct Findings ◽

Granulomatous Tissue ◽

Characteristic Features ◽

Surrounding Areas ◽

Ct Features

Two cases of idiopathic bronchiolitis obliterans organizing pneumonia (BOOP) with unusual CT findings are presented. On CT both cases exhibited crescentic and ring-shaped opacities, surrounding areas of groundglass attenuation, and associated with a nodular pattern in one patient and airspace consolidations in the second patient. CT—pathologic correlation disclosed that the central areas of groundglass attenuation corresponded to alveolar septal inflammation, in contrast to the denser periphery where granulomatous tissue in peripheral airspaces predominated. In the broad spectrum of CT findings, BOOP can exhibit specific CT features with regard to the crescentic or ring-shaped opacities with a central groundglass attenuation area. Since these features have not been described in any other disease, they might be characteristic features for the diagnosis of BOOP.

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CT Features of COVID-19 Pneumonia Differ Depending on the Severity and Duration of Disease

RöFo - Fortschritte auf dem Gebiet der Röntgenstrahlen und der bildgebenden Verfahren ◽

10.1055/a-1293-9163 ◽

2020 ◽

Author(s):

Jan Schaible ◽

Stefanie Meiler ◽

Florian Poschenrieder ◽

Gregor Scharf ◽

Florian Zeman ◽

...

Keyword(s):

Pleural Effusion ◽

Symptom Onset ◽

Ground Glass Opacity ◽

Ground Glass ◽

Time Interval ◽

Rt Pcr ◽

Severity Of Disease ◽

Duration Of Disease ◽

Bronchial Dilatation ◽

Ct Features

Background CT is important in the care of patients with COVID-19 pneumonia. However, CT morphology can change significantly over the course of the disease. To evaluate the CT morphology of RT-PCR-proven COVID-19 pneumonia in a German cohort with special emphasis on identification of potential differences of CT features depending on duration and severity of disease. Method All patients with RT-PCR-proven COVID-19 pneumonia and chest CT performed between March 1 and April 15, 2020 were retrospectively identified. The CT scans were evaluated regarding the presence of different CT features (e. g. ground glass opacity, consolidation, crazy paving, vessel enlargement, shape, and margin of opacifications), distribution of lesions in the lung and extent of parenchymal involvement. For subgroup analyses the patients were divided according to the percentage of parenchymal opacification (0–33 %, 34–66 %, 67–100 %) and according to time interval between symptom onset and CT date (0–5 d, 6–10 d, 11–15 d, > 15 d). Differences in CT features and distribution between subgroups were tested using the Mantel-Haenszel Chi Squared for trend. Results The frequency of CT features (ground glass opacity, consolidation, crazy paving, bronchial dilatation, vessel enlargement, lymphadenopathy, pleural effusion) as well as pattern of parenchymal involvement differed significantly depending on the duration of disease and extent of parenchymal involvement. The early phase of disease was characterized by GGO and to a lesser extent consolidation. The opacifications tended to be round and to some extent with sharp margins and a geographic configuration. The vessels within/around the opacifications were frequently dilated. Later on, the frequency of consolidation and especially crazy paving increased, and the round/geographic shape faded. After day 15, bronchial dilatation occurred, and lymphadenopathy and pleural effusion were seen more frequently than before. Conclusion The prevalence of CT features varied considerably during the course of disease and depending on the severity of parenchymal involvement. Radiologists should take into account the time interval between symptom onset and date of CT and the severity of disease when discussing the likelihood of COVID-19 pneumonia based on CT morphology. Key Points: Citation Format

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Evolution of CT Findings in Patients with COVID-19 Pneumonia

10.21203/rs.3.rs-16086/v1 ◽

2020 ◽

Author(s):

Ting Liang ◽

Carol C.Wu ◽

Zhe liu ◽

Chao Jin ◽

Huifang Zhao ◽

...

Keyword(s):

Symptom Onset ◽

Medical Records ◽

Disease Onset ◽

Time Intervals ◽

Travel History ◽

Ct Findings ◽

Severity Scores ◽

Increasing Trend ◽

Unilateral Involvement

Abstract Objectives To delineate the evolution of CT findings in patients with mild COVID-19 pneumonia outside of Wuhan.Methods CT images and medical records of 88 patients with confirmed mild COVID-19 pneumonia outside of Wuhan, a baseline and at least one follow-up CT were retrospectively reviewed. CT features including lobar distribution and presence of ground glass opacities (GGO), consolidation, and linear opacities, were analyzed on per patient basis during each of five time intervals spanning the three weeks after disease onset. Total severity scores were calculated.Results 85.2 % of patients had travel history to Wuhan or known contact with infected individuals. The most common symptoms were fever (84.1%) and cough (56.8%). The baseline CT was obtained on average 5 days from symptom onset. Four patients (4.5%) had negative initial CT. Significant differences were found among the time intervals in the proportion of pulmonary lesions that are 1) pure GGO, 2) mixed attenuation, 3) mixed attenuation with linear opacities, 4) consolidation with linear opacities, and 5) pure consolidation. The majority of patients had involvement of ≥ 3 lobes. Bilateral involvement was more prevalent than unilateral involvement. The proportions of patients observed to have pure GGO or GGO and consolidation decreased over time while proportion of patients with GGO and linear opacities increased. Total severity score showed an increasing trend in the first two weeks. Conclusions While bilateral GGO are predominant features, CT findings changed during different time intervals in the three weeks after symptom onset in patients with COVID-19.

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Prognostic factors of chest CT findings for ICU admission and mortality in patients with COVID-19 pneumonia

10.1101/2020.10.30.20223024 ◽

2020 ◽

Author(s):

Mohammad Ali Kazemi ◽

Hossein Ghanaati ◽

Behnaz Moradi ◽

Mohammadreza Chavoshi ◽

Hassan Hashemi ◽

...

Keyword(s):

Multivariate Analysis ◽

Prognostic Factors ◽

Poor Prognosis ◽

Underlying Disease ◽

Good Prognosis ◽

Chest Ct ◽

Icu Admission ◽

Ct Findings ◽

Pattern Distribution ◽

Ct Features

AbstractBackgroundStudies have shown that CT could be valuable for prognostic issues in COVID-19Objectiveto investigate the prognostic factors of early chest CT findings in COVID-19 patients.Materials and MethodsThis retrospective study included 91 patients (34 women, and 57 men) of RT-PCR positive COVID-19 from 3 hospitals in Iran between February 25, 2020, to march 15, 2020. Patients were divided into two groups as good prognosis, discharged from the hospital and alive without symptoms (48 patients), and poor prognosis, died or needed ICU care (43 patients). The first CT images of both groups that were obtained during the first 8 days of the disease presentation were evaluated considering the pattern, distribution, and underlying disease. The total CT-score was calculated for each patient. Univariate and multivariate analysis with IBM SPSS Statistics v.26 was used to find the prognostic factors.ResultsThere was a significant correlation between poor prognosis and older ages, dyspnea, presence of comorbidities, especially cardiovascular and pulmonary. Considering CT features, peripheral and diffuse distribution, anterior and paracardiac involvement, crazy paving pattern, and pleural effusion were correlated with poor prognosis. There was a correlation between total CT-score and prognosis and an 11.5 score was suggested as a cut-off with 67.4% sensitivity and 68.7% specificity in differentiation of poor prognosis patients (patients who needed ICU admission or died. Multivariate analysis revealed that a model consisting of age, male gender, underlying comorbidity, diffused lesions, total CT-score, and dyspnea would predict the prognosis better.ConclusionTotal chest CT-score and chest CT features can be used as prognostic factors in COVID-19 patients. A multidisciplinary approach would be more accurate in predicting the prognosis.

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CT appearance in the 330 patients with COronaVIrus disease 2019 (COVID-19) in Serbia

Vojnosanitetski pregled ◽

10.2298/vsp200725125k ◽

2020 ◽

pp. 125-125

Author(s):

Tijana Kosanovic ◽

Miroslav Misovic ◽

Vladimir Djukic ◽

Miodrag Lalosevic ◽

Marjana Djordjevic ◽

...

Keyword(s):

Symptom Onset ◽

Time Course ◽

Ct Scans ◽

Time Interval ◽

Imaging Features ◽

Ct Findings ◽

Group 3 ◽

Group 2 ◽

Onset Group ◽

Group 1

Background/Aim. The COronaVIrus Disease 2019 (COVID-19) primarily affects the respiratory system, so radiological diagnosis has been shown to be necessary. Chest computed tomography (CT) is to be shown the best modality in suspected COVID-19 cases for initial evaluation because CT findings may be present before the onset of symptoms. The purpose of this study is to show different CT imaging features or patterns in COVID-19 patients with a different time course and disease severity. Methods. This is a prospective cohort study that analysed 330 patients (the average age was 52.37?15.36) with confirmed COVID-19 via laboratory testing. During hospitalization, all patients included in the study underwent chest CT in order to assess the extent of changes in their lungs. Because chest CT images could show different imaging features or patterns in COVID-19 patients with a different time course and disease severity, we classified them into four categories: lung, bronchial, pleural and mediastinal changes. Based on the time interval between the onset of symptoms and the CT scan, all patients were divided into three groups: group 1 (CT scans done ?1 week after symptom onset); group 2 (CT scans done >1 to 2 weeks after symptom onset); group 3 (CT scans done >2 weeks after symptom onset). In order to more accurately monitor the distribution of changes in the lungs, bilateral lungs were divided into 12 ?lung? zones. Each zone was assigned a CT score. ?Total severity score? was calculated by summing the scores for each zone. Results. In 93.6% patients with COVID-19 the CT findings were positive. About 92.1% patients had multiple lesions. The lesions were bilateral in 87.6% of patients, had both peripheral and centrally localised lesions in 63.3% of patients, and occurred more frequently in posterior areas (93%), as well as in lower lung zones (91.2%). The average ?Total severity score? was 11.00 (7.00-16.00). The most common CT findings in all patients are the ground- glass opacities (97.7%), reticular pattern (91.3%), consolidation (71.5%) and fibrotic streaks (63.8%). When the time interval is monitored between onset of symptoms and the CT scan, it is noticed that in group 1 changes on CT were found in 80.0% of patients, in group 2 in 95.0%, and in group 3 in 99.4%. Conclusion. CT has proven to be a very important diagnostic method in COVID-19 patients, and together with clinical and laboratory findings, gives a complete picture of the patient's condition and significantly contributes to decision- making for further treatment.

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