Chest CT Examinations Research Articles

Application of CareDose 4D combined with Karl 3D technology in the low dose computed tomography for the follow-up of COVID-19

BackgroundCoronavirus disease 2019 (COVID-19) is a highly infectious disease caused by the new coronavirus. Previous studies have shown that the chest CT examination plays an important role in the diagnosis and monitoring of COVID-19. However, some patients with COVID-19 had low white blood cell counts and reduced lymphocyte ratios. Multiple CT examinations may cause radiation damages as well as increase the apoptosis of peripheral blood lymphocytes. A new low-dose CT method should be developed because the regular CT may aggravate the disease.MethodSixty cases were randomly divided into the study group (n = 30) and control group (n = 30). The lung window was reconstructed by Karl 3D iterative technique in the study group. The image quality was subjectively evaluated by two senior chest group diagnostic physicians using a 5-point double-blind method. The value of CT measurement and its standard deviation (SD) was used as an objective evaluation criteria. The volume of CT dose index (CTDIvol), dose length product (DLP) and effective dose (ED) from the two groups were compared and analyzed statistically.ResultThere was no significant difference in the occurrence rates of ground glass opacities, consolidation, crazy-paving pattern, fiber cable shadow and axial interstitial thickening between the study group and control group (p > 0.05). In addition, no significant difference was found for the subjective score of overall image quality and image noise level (SD) between the two groups (p > 0.05). However, significant differences was found in CTDIvol, DLP, and ED between the study group and the control group (p < 0.05). The effective dose of the study group was reduced by 76% compared to the control group.ConclusionCareDose 4D low-dose scanning combined with Karl 3D iterative reconstruction technology can not only greatly reduce the radiation dose, but also provide images that meet the diagnostic criteria of COVID-19, which can be used as a routine method for the follow-up of COVID-19 patients.

CT Features of Coronavirus Disease (COVID-19) in 30 Pediatric Patients.

OBJECTIVE. The purpose of this study is to characterize the CT findings of 30 children from mainland China who had laboratory-confirmed coronavirus disease (COVID-19). Although recent American College of Radiology recommendations assert that CT should not be used as a screening or diagnostic tool for patients with suspected COVID-19, radiologists should be familiar with the imaging appearance of this disease to identify its presence in patients undergoing CT for other reasons. MATERIALS AND METHODS. We retrospectively reviewed the CT findings and clinical symptoms of 30 pediatric patients with laboratory-confirmed COVID-19 who were seen at six centers in China from January 23, 2020, to February 8, 2020. Patient age ranged from 10 months to 18 years. Patients older than 18 years of age or those without chest CT examinations were excluded. Two cardiothoracic radiologists and a cardiothoracic imaging fellow characterized and scored the extent of lung involvement. Cohen kappa coefficient was used to calculate interobserver agreement between the readers. RESULTS. Among children, CT findings were often negative (77%). Positive CT findings seen in children included ground-glass opacities with a peripheral lung distribution, a crazy paving pattern, and the halo and reverse halo signs. There was a correlation between increasing age and increasing severity of findings, consistent with reported symptomatology in children. Eleven of 30 patients (37%) underwent follow-up chest CT, with 10 of 11 examinations (91%) showing no change, raising questions about the utility of CT in the diagnosis and management of COVID-19 in children. CONCLUSION. The present study describes the chest CT findings encountered in children with COVID-19 and questions the utility of CT in the diagnosis and management of pediatric patients.

Study on the Dynamic Changes in Chest CT Findings of COVID-19 Rehabilitated Patients

Objective: To study the dynamic changes in CT findings in COVID-19 (coronavirus disease-19, COVID-19) rehabilitated patients. Methods: A total of 148 chest CT images of 37 patients with COVID-19 were collected. In the first 21 days of the course of disease, 7 stages were performed every 3 days, and the eighth stage was performed after 21 days. Results: In the first chest CT examination, 19 cases were ground glass opacity, and 18 cases were high-density shadows with consolidation. The lesion shape was flaky and patchy in 33 cases. The percentage of consolidation, air bronchogram, fiber cord, interlobular septal thickening, subpleural line and pleural thickening were the highest on days 4-6, 7-9, 7-9, 10-12, 19-21 and 19-21, respectively. The highest percentage of disease progression was 80.00% on days 4-6, and then the percentage of disease progression gradually decreased with the extension of the onset time. The percentage of patients with improvement gradually increased from days 4-6, reaching 83.33% on days 16-18 and 100.00% on day 21. The percentage of lesion range enlargement and density increase was the highest on days 4-6, both of which were 60.00%，Then the percentage of both decreased gradually. The percentage of patients with lesion range reduction and density absorption dilution increased gradually with the onset time. There was no obvious regularity in the number of lesions. Conclusion: Patients with COVID-19 have regular changes in their lung conditions.

Radiation dose and image quality of noncontrast chest CT in domestic and imported main stream manufacturers

Objective: To compare the radiation dose and image quality of noncontrast chest CT and detection of ground-glass opacity pulmonary nodules (GGN) in domestic 128-slice spiral CT with the other CT scanners from three main stream manufacturers. Methods: From May 8, 2018 to October 31, 2018, noncontrast chest CT images from Neusoft 128-slice CT (75 males, 25 females, (42±16) years), dual-source 64-slice CT (53 males, 47 females, (50±16) years) and dual-source 128-slice CT scanners(69 males, 31 females, (62±17) years), Toshiba 128-slice CT (51 males, 49 females, (58±13) years) and GE 128-slice CT scanner (55 males, 45 females, (60±10) years) were collected in Eastern Theater Command and Tianjin People's Hospital. Radiation dose and image quality were evaluated.GGN detected both in Neusoft CT and dual-source CT scanners were used to analyze the displaying ability of lesions. Results: The noise in lung window of Neusoft CT ((37.8±4.9) HU) was higher than that of other mainstream CT scanners, and the noise in mediastinal window ((8.4±1.9) HU) was lower than that of GE 128-slice CT ((9.8±3.2) HU), but higher than that of dual-source CT and Toshiba 128-slice CT ((6.9±3.5)HU) (P<0.05). The absolute value of lung SNR in Neusoft CT was lower than that of other mainstream CT scanners, and the SNR in aorta (4.6±1.3) was lower than those of dual-source CT and Toshiba 128-slice CT(6.8±2.2) (P<0.05), but was not statistically significant compared with GE 128-slice CT (5.0±1.7). The mean CT value of upper lung ((-863±31) HU) at Neusoft CT was higher than 128-row dual-source CT ((-869±35) HU), and the mean CT value of aorta ((37±7) HU) was lower than that of Toshiba 128-slice CT((42±7) HU) and GE 128-slice CT ((45±9) HU) (P<0.05), while the mean CT values of the remaining lung and aorta were not statistically significant (P>0.05). The two readers had good to excellent consistency for image quality in five scanners (the highest kappa value=0.984). The delineation ability of Neusoft CT for GGN boundary was lower than that of dual-source CT (P<0.05), but had similar abilities to display the solid components, lobulation, burring, vacuoles, vascular bundle sign and pleural depression sign of GGN (all P>0.05). Radiation dose of Neusoft CT was lower than Toshiba 128-slice CT, but higher than dual-source 64-sliceCT and GE 128-slice CT scanners (P<0.05). Conclusions: With lower radiation dose than Toshiba 128-slice CT, Neusoft CT chest examination can meet the requirements of clinical diagnosis, but higher radiation dose and the lower image quality than dual-source CT and GE 128-slice CT shown in this study indicate further improvement is needed in terms of software and hardware.

CT imaging changes of corona virus disease 2019(COVID-19): a multi-center study in Southwest China

BackgroundSince the first case of a coronavirus disease 2019 (COVID-19) infection pneumonia was detected in Wuhan, China, a series of confirmed cases of the COVID-19 were found in Southwest China. The aim of this study was to describe the imaging manifestations of hospitalized patients with confirmed COVID-19 infection in southwest China.MethodsIn this retrospective study, data were collected from 131 patients with confirmed coronavirus disease 2019 (COVID-19) from 3 Chinese hospitals. Their common clinical manifestations, as well as characteristics and evolvement features of chest CT images, were analyzed.ResultsA total of 100 (76%) patients had a history of close contact with people living in Wuhan, Hubei. The clinical manifestations of COVID-19 included cough, fever. Most of the lesions identified in chest CT images were multiple lesions of bilateral lungs, lesions were more localized in the peripheral lung, 109 (83%) patients had more than two lobes involved, 20 (15%) patients presented with patchy ground glass opacities, patchy ground glass opacities and consolidation of lesions co-existing in 61 (47%) cases. Complications such as pleural thickening, hydrothorax, pericardial effusion, and enlarged mediastinal lymph nodes were detected but only in rare cases. For the follow-up chest CT examinations (91 cases), We found 66 (73%) cases changed very quickly, with an average of 3.5 days, 25 cases (27%) presented absorbed lesions, progression was observed in 41 cases (46%), 25 (27%) cases showed no significant changes.ConclusionChest CT plays an important role in diagnosing COVID-19. 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 of time.

Artifact of a Cardiac Pacemaker on Low Dose Chest CT

인공심장박동기와 제세동기를 삽입한 경우에 발생하는 인공물이 폐암의 조기 발견을 위해 시행되는 저선량 흉부CT에서 어떠한 영향을 주는지 알아보고자 한다. Lungman phantom과 인공심장 박동기를 이용하여 대조군과 실험군을 설정하여 인공심장박동기 주변 인공물의 CT value와 표준편차를 측정하였다. 인공심장박동기 주변으로 영상정보를 상실 (black-hole artifact) 하거나 선속 경화(streak artifact) 인공물을 확인하였다. 수검자들의 다양한 체형과 인공심장 박동기의 위치에 따라 폐암의 조기발견을 위한 저 선량 흉부CT 검사 시 수검자들에게 미세 병변의 발견을 저해하는 요인으로 작용할 것이라 생각되며 임상에서의 실질적인 검사에 적용할 수 있는 더 많은 연구가 필요할 것이다.We would like to find out how the artificial insemination of an artificial cardiac pacemaker and defibrillator affects the low-dose chest CT performed for early detection of lung cancer. Using Lungman phantom and artificial heart pacemaker, the control and experimental group were set up to measure the CT value and standard deviation of the man-made objects around the artificial heart pacemaker. Black-hole artifact (black-hole artifact) or pre-speed curing (streak artifact) artifacts were identified around the artificial heartbeater. Depending on the various body types of the examinees and the location of the artificial heart pacemakers, low dose chest CT examinations for early detection of lung cancer are thought to serve as inhibitors to the detection of fine lesions and will require more research to be applied to practical examinations in clinical trials.

Timely Diagnosis and Treatment Shortens the Time to Resolution of Coronavirus Disease (COVID-19) Pneumonia and Lowers the Highest and Last CT Scores From Sequential Chest CT.

OBJECTIVE. This study aims to assess correlations of the time from symptom onset to diagnosis and treatment with the time to disease resolution and CT scores as based on findings from sequential chest CT examinations. MATERIALS AND METHODS. Thirty patients with coronavirus disease (COVID-19) confirmed by reverse transcription-polymerase chain reaction analysis underwent chest CT examinations. Five patients who did not have positive CT findings or who had not yet fulfilled criteria for discharge from the hospital were excluded. CT scores were determined according to CT findings and lung involvement. The time from symptom onset to diagnosis and treatment was recorded for each patient, and on the basis of this information, patients with COVID-19 were divided into group 1 (patients for whom this interval was ≤ 3 days) and group 2 (those for whom this interval was > 3 days). The CT scores for each group were fitted using a Lorentzian line-shape curve to show the variation tendency during treatment. The differences in age, sex, and last CT scores determined before discharge between the two groups were analyzed, and correlations of the time from symptom onset to diagnosis and treatment with the time to disease resolution as well as with the highest CT score also underwent statistical analysis. RESULTS. A total of 25 subjects were enrolled in the study. The fitted tendency curves for group 1 and group 2 were significantly different, with peak points showing that the estimated highest CT score was 10 and 16 for each group, respectively, and the time to disease resolution was 6 and 13 days, respectively. The Mann-Whitney test showed that the last CT scores were lower for group 1 than for group 2 (p = 0.025), although the chi-square test found no difference in age and sex between the groups. The time from symptom onset to diagnosis and treatment had a positive correlation with the time to disease resolution (r = 0.93; p = 0.000) as well as with the highest CT score (r = 0.83; p = 0.006). CONCLUSION. Timely diagnosis and treatment are key to providing a better prognosis for patients with COVID-19.

Biological Effects of Low-Dose Chest CT on Chromosomal DNA.

Background Although the National Lung Screening Trial reported a significant reduction in lung cancer mortality when low-dose (LD) CT chest examinations are used for a diagnosis, their biologic effects from radiation exposure remain unclear. Purpose To compare LD CT and standard-dose (SD) CT for DNA double-strand breaks and chromosome aberrations (CAs) in peripheral blood lymphocytes. Materials and Methods Between March 2016 and June 2018, 209 participants who were referred to a respiratory surgery department for chest CT studies were prospectively enrolled in this study. Individuals were excluded if they had undergone radiography examinations within the last 3 days or had undergone chemotherapy or radiation therapy. Peripheral blood samples were obtained before and 15 minutes after CT. The number of γ-H2AX foci and unstable CAs in lymphocytes was quantified by immunofluorescent staining of γ-H2AX and by fluorescence in situ hybridization by using peptide nucleic acid probes for centromeres and telomeres, respectively. The Wilcoxon signed rank test was used for statistical analysis. Bonferroni correction was applied for multiple comparisons. Results Of the 209 participants (105 women, 104 men; mean age, 67.0 years ± 11.3 [standard deviation]), 107 underwent chest LD CT and 102 underwent chest SD CT. Sex distribution, age, and body size metrics were similar between the two groups. The median effective dose of LD CT and SD CT was 1.5 and 5.0 mSv, respectively. The number of double-strand breaks and CAs increased after a SD CT examination (γ-H2AX, P < .001; CAs, P = .003); the number of double-strand breaks and CAs before and after LD CT was not different (γ-H2AX, P = .45; CAs, P = .69). Conclusion No effect of low-dose CT on human DNA was detected. In the same setting, DNA double-strand breaks and chromosome aberrations increased after standard-dose CT. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Brenner in this issue.

Clinical analysis of 23 cases of 2019 novel coronavirus infection in Xinyang City, Henan Province

Objective To analyze the epidemiological characteristics and clinical features of the patients with 2019-nCoV infection, so as to provide basis for clinical diagnosis. Methods The epidemiology, clinical symptoms, laboratory and radiologic data of 23 patients with 2019-nCoV infection admitted to the Fifth People's Hospital of Xinyang City from January 22,2020 to January 29, 2020 were retrospectively analyzed. Results The 23 patients with 2019 nCov infection consisted of 15 men and 8 women, and the median age was 46.0 (40.5, 52.0) years (27-80 years); 9 of them had basic disease (39%), including hypertension (17%), cardiovascular diseases (17%), diabetes (9%), hypothyroidism (4%) and old tuberculosis (4%). All the 23 patients had contact history in Wuhan area or with confirmed infections. Clinical symptoms included: fever (100%), cough (70%), expectoration (43%), myalgia (26%), headache (17%) and dyspnea (17%), and the less common symptoms were diarrhea (4.3%). Blood routine test: white blood cells (WBC) 10 × 109/L in 2 cases (9%); lymphocytopenia in 13 cases (56%). All 23 patients had different degrees of infective lesions in chest CT examination, with 9 cases (39%) on one side and 14 cases (61%) on both sides. Classification: 19 mild cases, 4 severe cases, no critical or death case. Complications included acute respiratory distress syndrome [4 (17%)]. No case was reported with the damage of liver or kidney function and with secondary infection. Conclusions Epidemic history of contact, fever, pneumonia signs of chest CT, normal or decreased count of WBC and lymphocytopenia are the clinical basis for diagnosis of the disease. However, at present, the treatment of patients has not been completed, the effective treatment strategy and final prognosis are not clear. Key words: 2019 Novel coronavirus; Pneumonia; Acute respiratory distress syndrome

Deep Learning for Automatic Calcium Scoring in CT: Validation Using Multiple Cardiac CT and Chest CT Protocols.

Background Although several deep learning (DL) calcium scoring methods have achieved excellent performance for specific CT protocols, their performance in a range of CT examination types is unknown. Purpose To evaluate the performance of a DL method for automatic calcium scoring across a wide range of CT examination types and to investigate whether the method can adapt to different types of CT examinations when representative images are added to the existing training data set. Materials and Methods The study included 7240 participants who underwent various types of nonenhanced CT examinations that included the heart: coronary artery calcium (CAC) scoring CT, diagnostic CT of the chest, PET attenuation correction CT, radiation therapy treatment planning CT, CAC screening CT, and low-dose CT of the chest. CAC and thoracic aorta calcification (TAC) were quantified using a convolutional neural network trained with (a) 1181 low-dose chest CT examinations (baseline), (b) a small set of examinations of the respective type supplemented to the baseline (data specific), and (c) a combination of examinations of all available types (combined). Supplemental training sets contained 199-568 CT images depending on the calcium burden of each population. The DL algorithm performance was evaluated with intraclass correlation coefficients (ICCs) between DL and manual (Agatston) CAC and (volume) TAC scoring and with linearly weighted κ values for cardiovascular risk categories (Agatston score; cardiovascular disease risk categories: 0, 1-10, 11-100, 101-400, >400). Results At baseline, the DL algorithm yielded ICCs of 0.79-0.97 for CAC and 0.66-0.98 for TAC across the range of different types of CT examinations. ICCs improved to 0.84-0.99 (CAC) and 0.92-0.99 (TAC) for CT protocol-specific training and to 0.85-0.99 (CAC) and 0.96-0.99 (TAC) for combined training. For assignment of cardiovascular disease risk category, the κ value for all test CT scans was 0.90 (95% confidence interval [CI]: 0.89, 0.91) for the baseline training. It increased to 0.92 (95% CI: 0.91, 0.93) for both data-specific and combined training. Conclusion A deep learning calcium scoring algorithm for quantification of coronary and thoracic calcium was robust, despite substantial differences in CT protocol and variations in subject population. Augmenting the algorithm training with CT protocol-specific images further improved algorithm performance. © RSNA, 2020 See also the editorial by Vannier in this issue.

Chest CT in patients after lung transplantation: A retrospective analysis to evaluate impact on image quality and radiation dose using spectral filtration tin-filtered imaging.

ObjectivesThe purpose of this study was to investigate the impact of a 150kV spectral filtration chest imaging protocol (Sn150kVp) combined with advanced modeled iterative reconstruction (ADMIRE) on radiation dose and image quality in patients after lung-transplantation.MethodsThis study included 102 patients who had unenhanced chest-CT examinations available on both, a second-generation dual-source CT (DSCT) using standard protocol (100kVp, filtered-back-projection) and, on a third-generation DSCT using Sn150kVp protocol with ADMIRE. Signal-to-noise-ratio (SNR) was measured in 6 standardized regions. A 5-point Likert scale was used to evaluate subjective image quality. Radiation metrics were compared.ResultsThe mean time interval between the two acquisitions was 1.1±0.7 years. Mean-volume-CT-dose-index, dose-length-product and effective dose were significantly lower for Sn150kVp protocol (2.1±0.5mGy;72.6±16.9mGy*cm;1.3±0.3mSv) compared to 100kVp protocol (6.2±1.8mGy;203.6±55.6mGy*cm;3.7±1.0mSv) (p<0.001), equaling a 65% dose reduction. All studies were considered of diagnostic quality. SNR measured in lung tissue, air inside trachea, vertebral body and air outside the body was significantly higher in 100kVp protocol compared to Sn150kVp protocol (12.5±2.7vs.9.6±1.5;17.4±3.6vs.11.8±1.8;0.7±0.3vs.0.4±0.2;25.2±6.9vs.14.9±3.3;p<0.001). SNR measured in muscle tissue was significantly higher in Sn150kVp protocol (3.2±0.9vs.2.6±1.0;p<0.001). For SNR measured in descending aorta there was a trend towards higher values for Sn150kVp protocol (2.8±0.6 vs. 2.7±0.9;p = 0.3). Overall SNR was significantly higher in 100kVp protocol (5.0±4.0vs.4.0±4.0;p<0.001). On subjective analysis both protocols achieved a median Likert rating of 1 (25th-75th-percentile:1–1;p = 0.122). Interobserver agreement was good (intraclass correlation coefficient = 0.73).ConclusionsCombined use of 150kVp tin-filtered chest CT protocol with ADMIRE allows for significant dose reduction while maintaining highly diagnostic image quality in the follow up after lung transplantation when compared to a standard chest CT protocol using filtered back projection.

Postoperative acute exacerbation of interstitial lung disease after pneumonectomy: clinical analysis of four cases

Objective To summarize the clinical features, diagnosis and treatment of postoperative acute exacerbation of interstitial lung disease (ILD) after pneumonectomy. Methods The clinical data of 4 patients with postoperative acute exacerbation of ILD after pneumonectomy admitted in Beijing Hospital from October 2014 to November 2015 were retrospectively analyzed and related literatures were reviewed. Results Four patients were aged 60 to 74 years, including 3 males and 1 female, 2 of whom were idiopathic pulmonary fibrosis and 2 were connective tissue diseases related ILD. Chest high resolution computed tomography (HRCT) showed multiple lobular septal thickening, ground glass opacities, reticular shadow and strip shadow in both lungs. The patients developed acute dyspnea 2 to 3 days after pneumonectomy. In 2 cases, HRCT showed new patchy ground-glass opacities, reticular shadow and strip shadow in both lungs on the basis of preoperative pulmonary fibrosis. The sputum smear and culture showed no pulmonary infection in all 4 cases. Three patients were treated with glucocorticoids and 3 received mechanical ventilation with endotracheal intubation. One patient was successfully treated by early using adequate glucocorticoids, one patient improved after treatment but died after re-exacerbation, and the other two patients died after treatment failed. Conclusions Acute exacerbation of ILD after pneumonectomy often occurs in early postoperative period and it is characterized by progressive dyspnea. Chest CT and respiratory pathogen examination are helpful for early diagnosis. Postoperative acute exacerbation of ILD often lacks effective treatment, requires mechanical ventilation, and the prognosis is poor. Although glucocorticoids may be effective, re-exacerbation should be alert during treatment. Key words: Lung diseases, interstitial; Idiopathic pulmonary fibrosis; Pneumonectomy; Acute exacerbation

Serum Procalcitonin, Smoking History Combined Age Established a New Prediction Model for Predicting Dynamic Changes of Chest CT Images in Adult Community-Acquired Pneumonia (CAP) Patients.

Chest CT is widely used in clinical diagnosis and efficacy evaluation of CAP. While repeated chest CT examinations to evaluate dynamic changes in chest CT images in a short period of time is a common phenomenon, it causes a lot of waste of medical resources, and due to the large dose of CT radiation, it can cause some harm to the human body. The purpose of this study is to establish a new model to predict the dynamic chest CT image changes of CAP patients by analyzing the age, smoking history, and serum inflammatory markers. This is a retrospective study. All patients had received chest CT scan and serum inflammatory indexes were measured, including procalcitonin (PCT), high-sensitivity C-reactive protein (hs-CRP), white blood cell (WBC) and erythrocyte sedimentation rate (ESR). The second chest CT examination was performed after a week of treatment. General information on the medical record was also recorded (including age, smoking history, drinking history, and others). Main outcome measures were the changes of chest CT images, including absorption and non-absorption (including patients with progressive inflammation). Single factor analysis and two-dimensional logistic regression analysis were used to explore the independent risk factors of the new CT image change prediction model for CAP patients. ROC was used to evaluate the sensitivity and specificity of the new model. Among 220 patients with CAP, 150 patients had absorption in chest CT after a week of treatment (150/220), the remaining 70 patients had no absorption or even progression (70/220). Age, PCT, and smoking history were independent risk factors for inflammatory absorption. The AUC of ROC curve was 0.89 (95% CI 0.83 - 0.94), the sensitivity was 88.70%, and the specificity was 80.00%. A new prediction model consists of serum PCT, age, and smoking history has high specificity and sensitivity in predicting dynamic CT changes in adult CAP patients.

Can the examination time in CT and conventional x-ray be reduced in an emergency department with integrated radiology unit? A retrospective study

Quick radiological diagnosis is often needed in order to allow the clinicians to make a diagnosis. The purpose of this study was to measure examination time for radiology procedures before and after physical integration of a radiology unit in the ED. We retrospectively acquired data from the radiology information system and compared time from referral to end of radiological examination before and after physical integration of the radiology unit in the ED for 19,897 X-ray and 6,940 CT examinations. After integration examination time for X-ray examinations was reduced by 5 to 14 minutes (p&lt;0.001). For CT head and chest examination time was reduced by 7 to 15 minutes (p&lt;0.003) while examination time for CT abdomen was prolonged by 4 minutes (p=0.78).

Dynamic evolution of lung abnormalities evaluated by quantitative CT techniques in patients with COVID-19 infection.

Chest CT evaluation is often vital to determine patients suspected of COVID-19 pneumonia. The aim of this study was to determine the evolution of lung abnormalities evaluated by quantitative CT techniques in patients with COVID-19 infection from initial diagnosis to recovery. This retrospective study included 16 patients with COVID-19 infection from 30 January 2020 through 11 March 2020. Repeat chest CT examinations were obtained for three or more scans per patient. We measured total volume and mean CT value of lung lesions in each patient per scan, and then calculated the mass, which equals to volume × (CT value + 1000). Dynamic evolution of chest CT imaging as a function of time was fitted by non-linear regression model in terms of mass, volume and CT value, respectively. According to the fitting curves, we redefined the evolution of lung abnormalities: progressive stage (0-5 days), infection emerged and rapidly aggravated; peak stage (5-15 days), the greatest severity at approximate 7-8 days after onset; and absorption stage (15-30 days), the lesions slowly and gradually resolved.

Evaluation of the Adjuvant Efficacy of Natural Herbal Medicine on COVID-19: A Retrospective Matched Case-Control Study.

Since the outbreak of Corona Virus Disease 2019 (COVID-19) in Hubei province, the epidemic scale has increased rapidly, and no effective antiviral drug therapy has been identified yet. This study aimed to evaluate the adjuvant efficacy of Natural Herbal Medicine (NHM) combined with Western medicine in the treatment of COVID-19. We performed a retrospective, 1:1 matched, case-control study of the first cohort of hospitalized COVID-19-confirmed cases (January 17, 2020 to January 28, 2020). A total of 22 of the 36 confirmed patients were included in this study, split into two groups of 11: the NHM group (NHM combined standard Western medicine treatment) and control group (standard Western medicine treatment alone). All patients received appropriate supportive care and regular clinical and laboratory monitoring. Main evaluation indicators included improvement of clinical symptoms such as fever, cough and diarrhea after hospitalization; pathogen nucleic acid test result of respiratory tract and fecal specimens of the patient after hospitalization, and change of chest CT examination after hospitalization. The duration of fever in the NHM group ([Formula: see text] days) was significantly shorter than that in the control group ([Formula: see text] days) ([Formula: see text]). During the whole hospitalization period, the number of cases with diarrhea in the NHM group (two cases) was less than that in the control group (eight cases) ([Formula: see text]). Compared with the control group ([Formula: see text]), the duration for improvement (DI) of chest CT in the NHM group ([Formula: see text]) was significantly shorter ([Formula: see text]). Our results suggest that NHM could improve the clinical symptoms of COVID-19 patients and may be effective in treating COVID-19; thus, a larger, prospective, randomized, controlled clinical trial should be conducted to further evaluate the adjuvant efficacy of NHM in the treatment of COVID-19.

Evaluation of a two-image technique consisting of an axial and a coronal image generated by using the rib-flattening application: effect on reading time and diagnostic validity

Background/aim When reading a chest CT, a radiologist needs to evaluate each rib one by one due to complex curvy shape, which makes reporting a tiresome and time-consuming task. A new curved planar reformat application that flattens ribs on a single plane may find a place in the radiology reporting room. This study aimed to evaluate the effect of a two-image set created by using the rib-flattening application on the performance of a radiologist in detecting sclerotic rib lesions in cancer patients. Materials and methodsThe local Institutional Review Board approved this retrospective study. Two radiologists with different experience levels reviewed chest CT examinations of 106 patients (76 men, 30 women). We divided the patients into group A (n = 54), reviewed by a standard method, and group B (n = 52), reviewed by a standard method and the two-image set created on the rib-flattening application. Reading times, validity indices, and agreement levels with reference data were evaluated for both readers.ResultsThe median reading time of the junior examiner significantly decreased with the rib-flattening method (160.5 s vs. 70.0 s; P < 0.001). Diagnostic indices of the senior reader were improved significantly at per patient level (group A, AUC: 0.867; group B, AUC: 0.982; P = 0.046). The new method showed better agreement levels (kappa: 0.69 to 0.96) than the general method (kappa: 0.53 to 0.91).ConclusionBased on improved agreement levels, reading times, and diagnostic validity indices we conclude that a two-image set consisting of an axial and a coronal flattened-rib image may be used in conjunction with an ordinary exam.

Predicting Atrial Fibrillation from Automated Measurements of Left Atrial Volume Using Routine Chest CT Examination: Overlooked and Underrecognized Risk Factors.

Predicting Atrial Fibrillation from Automated Measurements of Left Atrial Volume Using Routine Chest CT Examination: Overlooked and Underrecognized Risk Factors.

Venous-phase chest CT with reduced contrast medium dose: Utilization of spectral low keV monoenergetic images improves image quality

PurposeIntravenous contrast administration is crucial in many CT examinations but also poses a potential risk to the patient. Monoenergetic images (MonoE) of dual-energy CT systems can virtually increase iodine attenuation and might improve image quality (IQ) if contrast dose is reduced. In this study, we investigated the influence of MonoE on lymph node (LN) delineation and IQ in chest CT examinations with significantly reduced contrast dose (50 %) of a novel dual-layer CT (DLCT). Method30 patients with clinically indicated reduced contrast dose underwent venous-phase chest DLCT scans. Conventional polyenergetic (PolyE) and MonoE images at 40 keV were calculated. The contrast difference of hilar lymph nodes (LN-CD) to the adjacent right pulmonary artery, their signal-to-noise (SNR) and contrast-to-noise-ratio (CNR) were determined. Subjective IQ was evaluated by 2 readers with respect to LN delineation and overall contrast enhancement (CE) using a 5-point-Likert-scale. ResultsLN-CD, SNR and CNR were significantly higher in MonoE than in PolyE images (LN-CD 92.3 ± 37.9 vs. 33.1 ± 14.5 HU, SNR 8.4 ± 3.4 vs. 4.0 ± 1.2, CNR 9.2 ± 6.3 vs. 2.6 ± 1.5; all p < 0.01). The LN delineation (3.7 ± 0.9 vs.1.8 ± 0.7; p < 0.01) and the CE (3.9 ± 0.7 vs. 2.3 ± 0.7; p < 0.01) were rated significantly better for MonoE than for PolyE images. There was no MonoE examination classified as non-diagnostic. ConclusionsSubjective and objective IQ parameters can be significantly improved for venous-phase chest CT examinations with reduced contrast doses by utilization of low-keV MonoE reconstructions. All MonoE images provided sufficient overall CE and therefore reduced contrast doses might be considered in a wider range of DLCT examinations and patients.

Recurrent Venous and Arterial Thrombosis By Prothrombin p.R596Q Heterozygous Mutation in a Chinese Patient: A Case Report and Literature Review

Objective: To investigate the causes of recurrent thrombosis in a young Chinese patient and review the related literature. Methods: To review the patient's medical history, routine imaging and laboratory testing (including anticoagulant protein activity), and extract DNA of peripheral blood from the patient to detect gene mutation of 76 coagulation and thrombosis-related genes using Hi-Q™ Sequencing. The positive results were amplified by PCR and verified by Sange sequencing, and the related literature was reviewed. Results: The male patient, 23 years old, was hospitalized on April 6th, 2018 because of "repeated chest pain, hemoptysis and asthma for 7 days". The patient underwent thrombolysis in the local hospital in 2015 because of deep vein thrombosis in the right lower extremity. In 2016, he took warfarin orally for intracranial venous sinus thrombosis for one year, and stopped taking the medicine 2 months before this admission. He Had a history of chronic hepatitis B. There was no inducements for the above symptoms before admission. Chest CT examination on April 3th showed that there were infection foci in the lower lobe of the right lung, sub-pleural shadow in the middle lobe of the right lung and the lingual lobe of the left lung, and bilateral pleural adhesion was possible. Pulmonary CTA showed that there were filling defects in the main trunk of both pulmonary arteries. There was no abnormality in the arteriovenous vessels of both lower extremities by B-mode ultrasonography. Chest CT scan after transferred to our hospital showed inflammation and a few strings in both lungs, pericardial effusion: widening of pulmonary artery, bilateral pleural effusion with local expansion of lower lung tissue. D-dimer was 27.59 mg/L. After diagnosed as pulmonary thrombosis, pulmonary infection and chronic viral hepatitis B, the patient was treated with "Rivaroxaban 10mg Bid" for anticoagulation, symptomatic anti-infection and reducing pulmonary artery pressure. Relevant examinations after admission indicated that there were no obvious abnormalities in blood routine , biochemical testing, autoantibody, ANCA and sputum culture. C-reactive protein was 93.6 mg/L, blood homocysteine homocysteine level was within normal range, and multicolour B ultrasonography indicated the formation of venous thrombosis in the right lower extremity. Fibrinogen: 4.9g/l, D-dimer: 14.64mg/L; Antithrombin activity: 94.2%, Protein S activity: 89.1%, Protein C activity: 90%. From April 14th, he was treated with 0.6ml q12h of enoxaparin and from April 24th with warfarin . Because of swelling of the right lower extremity, the right external iliac artery and the right lower extremity venous thrombosis were detected by mutilcolour B ultrasonography on April 26th. The patient refused to undergo IVC filter implantation and continued with warfarin anticoagulation therapy. During hospitalization, all exon regions and lateral intron regions of 76 genes closely related to coagulation and thrombosis diseases were sequenced using Ion PI™ Hi-Q™ Sequencing 200 Kit. The results indicated that prothrombin (NM000506) exon 14 c.1787G &gt; A heterozygous missense mutation resulted in p.R598Q. The presence of this mutation was confirmed by PCR amplification of patient's DNA. Both SIFT database and Polyphen2 database predicted that the mutation site might affect protein function; the p. R596Q mutation was detected in a 60-year-old male patient with deep venous thrombosis (PMID: 23265743). R598 is a highly conserved amino acid, which participates in the formation of prothrombin Na + ion binding ring. R598Q causes conformational changes, keeping thrombin in enzymatic activity, and increases the risk of thrombosis (PMID: 29382582). Conclusion: The heterozygous mutation of prothrombin p. R596Q is the molecular pathological cause of the recurrent multiple site venous and artery thrombosis in this young Chinese patient. The mutation is reported firstly in China. Disclosures No relevant conflicts of interest to declare.