Background: Few studies have classified chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) and analyzed their correlations with prognosis. The present study aimed to evaluate retrospectively the clinical and chest CT findings of COVID-19 and to analyze CT findings and determine their relationships with clinical severity. Methods: Chest CT and clinical features of 271 COVID-19 patients were assessed. The presence of CT findings and distribution of parenchymal abnormalities were evaluated, and CT patterns were classified as bronchopneumonia, organizing pneumonia (OP), or diffuse alveolar damage (DAD). Total extents were assessed using a visual scoring system and artificial intelligence software. Patients were allocated to two groups based on clinical outcomes, that is, to a severe group (requiring O-2 therapy or mechanical ventilation, n = 55) or a mild group (not requiring O-2 therapy or mechanical ventilation, n = 216). Clinical and CT features of these two groups were compared and univariate and multivariate logistic regression analyses were performed to identify independent prognostic factors. Results: Age, lymphocyte count, levels of C-reactive protein, and procalcitonin were significantly different in the two groups. Forty-five of the 271 patients had normal chest CT findings. The most common CT findings among the remaining 226 patients were ground-glass opacity (98%), followed by consolidation (53%). CT findings were classified as OP (93%), DAD (4%), or bronchopneumonia (3%) and all nine patients with DAD pattern were included in the severe group. Uivariate and multivariate analyses showed an elevated procalcitonin (odds ratio (OR), 2.521; 95% confidence interval (CI], 1.001-6.303, P= 0.048), and higher visual CT scores (OR, 1.137; 95% CI, 1.042-1.236; P= 0.003) or higher total extent by AI measurement (OR, 1.048; 95% CI, 1.020-1.076; P< 0.001) were significantly associated with a severe clinical course. Conclusion: CT findings of COVID-19 pneumonia can be classified into OP, DAD, or bronchopneumonia patterns and all patients with DAD pattern were included in severe group. Elevated inflammatory markers and higher CT scores were found to be significant predictors of poor prognosis in patients with COVID-19 pneumonia.

Purpose To correlate the results of histopathologic subtyping and grading of lung adenocarcinoma with maximum standardized uptake values (SUVmax) on positron emission tomography (PET)/computed tomography and apparent diffusion coefficient (ADC) values on diffusion‐weighted MRI (DWI). Materials and Methods Forty‐three patients were included. The SUVmax and mean ADC values of tumors were measured and correlated with the histologic subtypes and grades of lung adenocarcinomas based on the IASLC/ATS/ERS classification scheme. Disease‐free survival (DFS) was estimated by using the Kaplan‐Meier method, and the log‐rank test was used to evaluate differences among three histologic grades or subgroups classified with imaging biomarker study results. Results Five (12.5%) tumors belonged to low grade, 30 (70%) to intermediate grade, and 8 (18.5%) to high grade, and patients with low‐grade histology had lower risk of recurrence than those with intermediate‐ or high‐grade histology ( P = 0.048). A significant difference in SUVmax and mean ADC values was observed among three histologic grades ( P s < 0.001). Regarding DFS, lower metabolic (PET) activity or higher functional (DWI) diffusivity showed longer DFS. When patients (n = 30; 70% of patients) with intermediate histologic grade were subgrouped in consideration of both SUVmax and mean ADC results, combining metabolic and functional criteria helped stratify patients more precisely ( P = 0.006). Conclusion SUVmax and mean ADC value correlate well with the histologic grades in lung adenocarcinomas, and combining both imaging biomarker study results leads to more useful stratification of patients into different prognostic subsets than the results of each study. J. Magn. Reson. Imaging 2013;38:905–913. © 2013 Wiley Periodicals, Inc.

Background Digital tomosynthesis considerably reduces problems created by overlapping anatomy compared with chest X-ray (CXR). However, digital tomosynthesis requires a longer scan time compared with CXR, and thus may be vulnerable to motion artifacts. Purpose To compare the diagnostic performance of digital tomosynthesis in subjects with and without respiratory motion artifacts. Material and Methods The institutional review board approved this retrospective study, and the requirement for written informed consent was waived. A total of 46 subjects with imaging containing respiratory motion artifacts were enrolled in this study, 18 of whom were positive and 28 of whom were negative for lung nodules on computed tomography (CT). The control group was comprised of 92 age-matched subjects with imaging devoid of motion artifacts. Of these, 36 were positive and 56 were negative for lung nodules on subsequent CT scan. The size criteria of nodules were 4–10 mm. Three chest radiologists independently evaluated the radiographs and digital tomosynthesis images for the presence of pulmonary nodules. Multireader multicase receiver-operating characteristic (ROC) analyses was used for statistical comparisons. Results Within the control group, the areas under curve (AUC) for observer performances in detecting lung nodules on digital tomosynthesis was higher than that on CXR ( P = 0.017). Within the study group, there were no significant differences in AUCs for observer performances ( P = 0.576). Conclusion When no motion artifacts are present, the detection performance of nodules (4–10 mm) on digital tomosynthesis is significantly better than that on CXR, whereas there is not a significant difference in cases with motion artifacts.

Tumor response may be assessed readily by the use of Response Evaluation Criteria in Solid Tumor version 1.1. However, the criteria mainly depend on tumor size changes. These criteria do not reflect other morphologic (tumor necrosis, hemorrhage, and cavitation), functional, or metabolic changes that may occur with targeted chemotherapy or even with conventional chemotherapy. The state-of-the-art multidetector CT is still playing an important role, by showing high-quality, high-resolution images that are appropriate enough to measure tumor size and its changes. Additional imaging biomarker devices such as dual energy CT, positron emission tomography, MRI including diffusion-weighted MRI shall be more frequently used for tumor response evaluation, because they provide detailed anatomic, and functional or metabolic change information during tumor treatment, particularly during targeted chemotherapy. This review elucidates morphologic and functional or metabolic approaches, and new concepts in the evaluation of tumor response in the era of personalized medicine (targeted chemotherapy).

Purpose: To present the serial computed tomographic (CT) findings of lung abnormalities in Mycobacterium massiliense pulmonary disease compared with those in Mycobacterium abscessus disease.Materials and Methods: The institutional review board approved this retrospective study and waived informed consent. Serial chest CT scans of M massiliense (n = 34) and M abscessus (n = 24) pulmonary diseases were retrospectively reviewed. Patients were treated with clarithromycin- containing combination antibiotics regimen, and sputum examinations were performed regularly. CT scans were obtained at the beginning of antibiotic therapy, at the end of 4-week hospitalization, and at the time of 12-month antibiotic therapy.Results: All patients with M massiliense disease had sputum conversion during treatment, whereas 50% of patients with M abscessus disease had sputum conversion. The most common CT findings of M massiliense disease at presentation were cellular bronchiolitis (n = 34, 100%), bronchiectasis (n = 34, 100%), consolidation (n = 33, 97%), nodules (n = 32, 94%), and cavities (n = 15, 44%). These findings were similar in M abscessus disease. Thirty (88%) patients with M massiliense disease had decrease in overall CT score at 12-month therapy, whereas only eight (33%) patients with M abscessus disease had a decrease (P < .0001). Improvement was noticeable in cellular bronchiolitis and cavity in M massiliense disease.Conclusion: Common CT findings of M massiliense diseases overlap with those of M abscessus disease. However, responses to antibiotic treatment are much different; in M massiliense disease, negative sputum conversion is accomplished in all patients and serial CT scans show improvement in most patients. (c) RSNA, 2012

A fibroepithelial polyp of the bronchus is a rare, benign, and endobronchial tumor, histologically consisting of fibrovascular stroma covered by normal respiratory epithelium. We report a case of a fibroepithelial polyp arising from the left main bronchus. On CT, a characteristic lobulating contour of the endobronchial nodule was well visualized, which histopathologically represented a typical papillary growth pattern of the nodule. Such a lobulating contour of the nodule might help make a correct diagnosis of this rare disease among other various endobronchial neoplasms.

Aim The aim of this study was to evaluate retrospectively the chest computed tomography findings of influenza A (H1N1) pneumonia and their relationship with clinical outcome. Methods Chest computed tomography findings and clinical outcomes of 76 patients with influenza A (H1N1) pneumonia were assessed. Computed tomography findings were evaluated for the presence and distribution of parenchymal abnormalities, which were then classified into 3 patterns: bronchopneumonia, cryptogenic organizing pneumonia (COP), and acute interstitial pneumonia (AIP) patterns. Clinical courses were divided into 2 groups on the basis of necessitating admission to intensive care unit or mechanical ventilation therapy (group 1) or not (group 2). Results Lung abnormalities consisted of ground-glass opacity (93%, 71 patients), consolidation (66%, 50 patients), small nodules (61%, 46 patients), and tree-in-bud sign (22%, 17 patients). Lesions were classified into bronchopneumonia (49%, 37 patients), COP (30%, 23 patients), AIP (18%, 14 patients), and unclassifiable (3%, 2 patients) patterns. Patients with AIP pattern had a tendency to belonging to group 1, accounting for 40% (8 of 20 patients) of group 1 course and only 11% (6 of 56 patients) of group 2 course (P = 0.004). Conclusions Computed tomography findings of influenza A (H1N1) pneumonia in adults can be classified into COP, AIP, and bronchopneumonia patterns. Patients presenting with AIP pattern have a tendency to show poor prognosis.

PURPOSE: To assess retrospectively the chest radiograph and CT findings of influenza A pneumonia and to evaluate whether pattern analysis of CT scans helps predict clinical outcome.