Interpretation of CT images of pulmonary mucinous adenocarcinoma / 中国综合临床

Pulmonary mucinous adenocarcinoma (PMA) is relatively rare. On chest CT, it can be divided into two types: mass type and pneumonia type. Mass type PMA is more common and is difficult to distinguish from other nonsmall cell lung cancer. It is a solid or partial solid nodule or mass, predominantly located in the peripheral field of the lung with lobulation, spiculation, and more prone “vacuole sign”. Pneumonia type PMA has a poor prognosis and is more likely to develop into diffuse, multifocal and multilobular lesions similar to inflammatory manifestations, indicating dissemination along the airway. Typical signs include large areas of low density, low enhancement consolidation, and “dead tree sign”.

The Value of Spiral Chest Computed Tomography Scan in the Diagnosis of Asymptomatic Coronavirus Carriers among Paranasal Sinus and Pharynx Surgery Candidates

Abstract Introduction The nasopharynx and oropharynx are the main colonization sites of coronavirus. Therefore, patients with paranasal sinuses and pharyngeal problems (ear, nose, and throat [ENT] patients) predispose coronavirus infection. Ear, nose, and throat patients with concomitant asymptomatic coronavirus infection may develop severe pneumonia following surgical procedures. As a result, presurgical screening for coronavirus infection is a substantial concern. Objective We evaluated the usefulness of a spiral chest computed tomography (CT) scan in the diagnosis of asymptomatic coronavirus infection in the presurgical assessment of ENT patients Methods In this study, candidates of paranasal sinus or pharyngeal surgery were evaluated for coronavirus infection. Patients with neither history of coronavirus disease 2019 (COVID-19) nor compatible symptoms and signs were screened for asymptomatic coronavirus infection. These patients composed two groups: the first group underwent a reverse transcription polymerase chain reaction (RT-PCR) test of nasopharyngeal sample and spiral chest CTscan, but for the second one, only the latter was performed. Results In the first group, which consisted of 106 patients, 11 (10.4%) cases had positive RT-PCR test results, and 17 (16%) patients showed positive findings in favor of coronavirus infection in the spiral chest CT scan. In the second group, which consisted of 173 patients, 34 (19.7%) cases had positive chest CT scan results. Conclusion The chest CT scan has a valuable role in the early diagnosis of asymptomatic coronavirus carriers in patients highly predisposed to infection, especially in low resource areas, where the RT-PCR test is unavailable.

The predictive value of chest x-ray and plain chest CT scan as adjunct screening tools for COVID-19 patients in a national tertiary infectious disease hospital from March 1 to November 30, 2020

Background@#COVID-19 is diagnosed via Real Time Reverse Transcription Polymerase Chain Reaction (RT-PCR), with plain chest CT and chest x-ray as adjuncts. In the Philippines, chest x-ray is used as initial screening in assessing potential COVID-19 cases, with plain chest CT scan not routinely used due to higher cost and decreased availability.@*Objective@#This study determined the validity of chest x-ray and plain chest CT as initial screening tools for admitted COVID-19 patients from March 1 to November 30, 2020, at San Lazaro Hospital, comparing these with RT-PCR testing for COVID-19 as initial basis for considering a patient as a possible case of COVID-19.@*Methods@#This was a cross-sectional study of radiographic literature of admitted COVID-19 patients from March 1 to November 30, 2020, at San Lazaro Hospital, all with confirmatory RT-PCR, chest X-rays, and plain chest CTs. Baseline chest x-rays, with initial plain chest CT results, were compared with RT-PCR results. A tally was made, noting radiographic findings on both Chest X-ray and Plain Chest CT most frequently seen among patients with corresponding positive real time RT-PCR results.@*Results@#Chest X-rays done < 2 days from admission revealed involvement of both lungs, with infiltrates located centrally and peripherally, with major predilection for both lower lobes. Plain chest CT was similar, with ground glass opacities as the most common finding, consolidation second. Chest x-ray had a sensitivity of 88.11%, plain chest CT 94.71%. Sensitivity of combined chest x-ray and plain chest CT was 86.78%. Specificity and predictive value were not computed due to non-inclusion of admitted patients with COVID negative RT-PCR swab.@*Conclusion@#Chest X-ray and plain chest CT are useful modalities with high sensitivity in screening patients with fever, cough, and colds on admission. However, initial chest x-ray and plain chest CT scan results do not translate into a prognosis without context of initial diagnostics and management done during confinement.

Interpretation of CT images of lung adenosquamous carcinoma / 中国综合临床

Lung adenosquamous carcinoma (ASC) is a rare histological subtype of lung cancer, which has a worse prognosis than simple lung adenocarcinoma and lung squamous cell carcinoma. ASC was predominantly located in the peripheral field of the lung with heterogeneous attenuation and the most common features included lobulation, spiculation, pleural tail sign, necrosis and cavitation on chest CT images. However, the imaging features of ASC are not specific. Therefore, acquring accurate pathological diagnosis and adequate treatment as soon as possible are very important.

Impact of COVID-19 on chest CT scan frequency in a general hospital / 中国辐射卫生

@#<b>Objective</b> To explore the effect of coronavirus disease 2019 (COVID-19) on the frequency of chest CT scan. <b>Methods</b> A retrospective study was conducted to extract information on the number of outpatient, emergency, and inpatient visits and patients who had chest CT imaging examination from January 1 to December 31, 2020 and in the same period in 2019 through the hospital’s medical data platform for analysis, and the chi-square test was used to analyze whether the difference in the proportion of patients who had chest CT imaging examination between 2019 and 2020 was statistically significant. <b>Results</b> The proportion of outpatients and emergency patients with chest CT examination was significantly higher in 2020 than in 2019 (2.48% <i>vs</i> 1.47%, <i>χ</i>² = 581.7, <i>P</i> < 0.000). The proportion of inpatients who underwent chest CT examination was significantly higher in 2020 than in 2019 (35.47% <i>vs</i> 28.01%, <i>χ</i>² = 182.0, <i>P</i> < 0.000). <b>Conclusion</b> Under the COVID-19 epidemic, the proportion of chest CT examination in this hospital in 2020 shows a significant upward trend compared with the same period in 2019, which will increase the collective dose due to medical exposure, and the hospital should pay attention to the determination of the legitimacy of chest CT scan.

Diagnostic performance of the RSNA-proposed classification for COVID-19 pneumonia versus pre-pandemic controls

Abstract Objective To evaluate the diagnostic accuracy of the Radiological Society of North America (RSNA) classification system for coronavirus disease 2019 (COVID-19) pneumonia compared to pre-pandemic chest computed tomography (CT) scan images to mitigate the risk of bias regarding the reference standard. Materials and methods This was a retrospective, cross-sectional, diagnostic test accuracy study. Chest CT scans, carried out from May 1 to June 30, 2020, and from May 1 to July 17, 2017, were consecutively selected for the COVID-19 (positive reverse transcription-polymerase chain reaction [RT-PCR] for severe acute respiratory syndrome coronavirus 2 result) and control (pre-pandemic) groups, respectively. Four expert thoracic radiologists blindly interpreted each CT scan image. Sensitivity and specificity were calculated. Results A total of 160 chest CT scan images were included: 79 in the COVID-19 group (56 [43.5-67] years old, 41 men) and 81 in the control group (62 [52-72] years old, 44 men). Typically, an estimated specificity of 98.5% (95% confidence interval [CI] 98.1%-98.4%) was obtained. For the indeterminate classification as a diagnostic threshold, an estimated sensitivity of 88.3% (95% CI 84.7%-91.7%) and a specificity of 79.0% (95% CI 74.5%-83.4%), with an area under the curve of 0.865 (95% CI 0.838-0.895), were obtained. Conclusion The RSNA classification system shows strong diagnostic accuracy for COVID-19 pneumonia, even against pre-pandemic controls. It can be an important aid in clinical decision-making, especially when a typical or indeterminate pattern is found, possibly advising retesting following an initial negative RT-PCR result and streamlining early management and isolation.

The diagnostic value of chest CT and MRI for lymph node metastasis of thoracic esophageal cancer / 中国辐射卫生

Objective To compare the clinical value of chest CT and Magnetic Resonance Imaging (MRI) in the diagnosis of lymph node metastasis of thoracic esophageal cancer. Methods A retrospective analysis of 90 patients with thoracic esophageal cancer lymph node metastasis diagnosed and treated in our hospital from July 2015 to June 2019. All patients underwent chest CT and MRI scans after admission, and the lesion tissue samples were taken for pathological examination after surgery. Physical examination, with pathological diagnosis results as the gold standard, analyze the sensitivity and specificity of chest CT and MRI. Results The sensitivity, specificity, positive predictive value, and negative predictive value of MRI scan was 88.73%, 94.74%, 98.44%, and 69.23%, respectively, which were higher than 69.01%, 52.63%, 84.48%, and 31.25% of the chest CT scan. In the distribution of lymph node metastasis, the middle of the thorax was the largest, and the proportions of the upper, middle, and lower thoraxes were 26.67%, 60.00%, and 13.33%, respectively. The uppermost mediastinal and paratracheal lymph nodes had the largest metastases in the upper thorax, the paratracheal and subcarinal lymph nodes in the middle thoracic segment had the most metastasis, and the next to the cardia and left gastric artery lymph nodes in the lower thorax had the largest metastases. The accuracy of MRI diagnosis is higher than that of chest CT. Conclusion Both chest CT and MRI can diagnose lymph node metastasis of thoracic esophageal cancer. The diagnostic value of MRI in diagnosing lymph node metastasis of thoracic esophageal cancer is better than chest CT. The diagnostic accuracy of MRI in each part of the lymph node is higher than that of chest CT, which can show the lymph nodes more clearly in transfer situation.

The chest CT finding of pleural plaques and asbestosis in lung cancer patients: A case study

@#A sixty-eight years old man was referred to the hospital for evaluation of lung adenocarcinoma treatment. Chest computed tomography (CT) imaging showed lung nodule, pleural plaques, ground-glass opacity, and parenchymal bands related to asbestosis. Pleural plaques are the proxy of asbestos exposure, and asbestosis is lung parenchymal fibrosis caused by asbestos. The interview revealed that the patient had worked as an owner of a construction firm for more than 37 years. Construction workers are at high risk of getting asbestos-related diseases because some building materials have asbestos. This case study aimed to describe chest CT findings of asbestosis and pleural plaques that suggest the presence of asbestos exposure in a lung cancer case. This case showed the pivotal role of chest CT to define asbestos-related lung diseases and a structured interview to obtain past asbestos exposure.

Tomographic score (RAD-Covid Score) to assess the clinical severity of the novel coronavirus infection

ABSTRACT Objectives: The severity of pulmonary Covid-19 infection can be assessed by the pattern and extent of parenchymal involvement observed in computed tomography (CT), and it is important to standardize the analysis through objective, practical, and reproducible systems. We propose a method for stratifying the radiological severity of pulmonary disease, the Radiological Severity Score (RAD-Covid Score), in Covid-19 patients by quantifying infiltrate in chest CT, including assessment of its accuracy in predicting disease severity. Methods: This retrospective, single-center study analyzed patients with a confirmed diagnosis of Covid-19 infection by real-time reverse-transcriptase polymerase chain reaction, who underwent chest CT at hospital admission between March 6 and April 6, 2020. CT scans were classified as positive, negative, or equivocal, and a radiological severity score (RAD-Covid Score) was assigned. Clinical severity was also assessed upon hospital admission. Results: 658 patients were included. Agreement beyond chance (kappa statistic) for the RAD-Covid Score was almost perfect among observers (0.833), with an overall agreement of 89.5%. The RAD-Covid Score was positively correlated with clinical severity and death, i.e., the higher the RAD-Covid Score, the greater the clinical severity and mortality. This association proved independent of age and comorbidities. Accuracy of this score was 66.9%. Conclusions: The RAD-Covid Score showed good accuracy in predicting clinical severity at hospital admission and mortality in patients with confirmed Covid-19 infection and was an independent predictor of severity.

Chest CT interpretation of organized pneumonia / 中国综合临床

Organizing pneumonia (OP) is a common lung interstitial disease.On chest CT, the main imaging manifestations of OP are consolidation and/or nodules with air bronchogram and traction bronchiectasis, predominantly peribronchovascular and subpleural regions." Reverse halo" sign, band-like consolidation and paralobular consolidation are also can be seen.Migratory behavior of lesions may be evident in follow up studies.The diagnosis of OP is a comprehensive analysis based on imaging combined with clinical and pathological findings.

Clinical features of 2019 novel coronavirus infection patients and a feasible screening procedure / 中华急诊医学杂志

Objective@#To study the clinical characteristics of 2019 coronavirus (2019-nCoV) pneumonia patients and make a feasible screening process in fever clinic.@*Methods@#Epidemiologic features, clinical presentation, laboratory findings and image features of the screened patients were retrospectively collected and analyzed.@*Results@#Totally, 46 patients were screened, 9 of them were laboratory-confirmed 2019-nCoV infection, and others were defined as laboratory-excluded patients. Laboratory-confirmed patients had higher frequency of travelling or residence in Wuhan within two weeks of onset (P<0.05), but there were no differences on age, sex, other epidemiologic features and comorbidities between the two groups (P>0.05). The most common feature of the laboratory-confirmed patients was fever (100%), but the symptoms showed no differences between the two groups (P>0.05). Laboratory-confirmed patients had lower white blood cell count than the laboratory-excluded patients (P<0.05), and all of them had pneumonia in chest CT scan. None of the patients with normal chest CT had positive 2019-nCoV nucleic acid test.@*Conclusions@#No specific symptom was helpful in the diagnosis of 2019-nCoV infection. However, patients without chest CT scan changes had a very low risk of 2019-nCoV infection despite of the epidemiologic history and fever. We recommended a screening procedure that might be helpful to reduce the rate of miss diagnosis and improve screening efficiency.

Association of Chest CT-Based Quantitative Measures of Muscle and Fat with Post-Lung Transplant Survival and Morbidity: A Single Institutional Retrospective Cohort Study in Korean Population

OBJECTIVE: Abnormal body composition is an important modifiable risk factor in lung transplantation. Therefore, precise quantification of different body components, including muscle and fat, may play an important role in optimizing outcomes in lung transplant patients. The purpose of the study was to investigate the prognostic significance of muscle and subcutaneous fat mass measured on chest CT with regard to lung transplantation survival and other post-transplant outcomes. MATERIALS AND METHODS: The study population included 45 consecutive adult lung transplant recipients (mean age of 47.9 ± 12.1 years; 31 males and 14 females) between 2011 and 2017. Preoperative cross-sectional areas of muscle and subcutaneous fat were semi-automatically measured on axial CT images at the level of the 12th thoracic vertebra (T12). Additional normalized indexed parameters, adjusted for either height or weight, were obtained. Associations of quantitative parameters with survival and various other post-transplant outcomes were evaluated. RESULTS: Of the 45 patients included in the present study, 10 mortalities were observed during the follow-up period. Patients with relative sarcopenia (RS) classified based on height-adjusted muscle area with a cut-off value of 28.07 cm²/m² demonstrated worse postoperative survival (log-rank test, p = 0.007; hazard ratio [HR], 6.39:1) despite being adjusted for age, sex, and body mass index (HR, 8.58:1; p = 0.022). Weight-adjusted parameters of muscle area were negatively correlated with duration of ventilator support (R = −0.54, p < 0.001) and intensive care unit (ICU) stay (R = −0.33, p = 0.021). CONCLUSION: Patients with RS demonstrate worse survival after lung transplantation that those without RS. Additionally, quantitative parameters of muscles measured at the T12 level on chest CT were associated with the duration of post-lung transplant ventilator support and duration of stay in the ICU.

Four-Dimensional Thoracic CT in Free-Breathing Children

In pediatric thoracic CT, respiratory motion is generally treated as a motion artifact degrading the image quality. Conversely, respiratory motion in the thorax can be used to answer important clinical questions, that cannot be assessed adequately via conventional static thoracic CT, by utilizing four-dimensional (4D) CT. However, clinical experiences of 4D thoracic CT are quite limited. In order to use 4D thoracic CT properly, imagers should understand imaging techniques, radiation dose optimization methods, and normal as well as typical abnormal imaging appearances. In this article, the imaging techniques of pediatric thoracic 4D CT are reviewed with an emphasis on radiation dose. In addition, several clinical applications of pediatric 4D thoracic CT are addressed in various thoracic functional abnormalities, including upper airway obstruction, tracheobronchomalacia, pulmonary air trapping, abnormal diaphragmatic motion, and tumor invasion. One may further explore the clinical usefulness of 4D thoracic CT in free-breathing children, which can enrich one's clinical practice.

Size-specific dose estimation for chest CT examination in pediatric and adult patients / 中华放射医学与防护杂志

Objective To compare the differences in radiation doses from CT scanning between children of different age groups and adult patients by using both traditional radiation dose assessment parameters and size-specific dose estimates (SSDE).Methods A total of 406 patients undergoing lung CT examination were studied.They were sampled retrospectively and continuously from the Union Hospital and divided into six groups by age distritution (0-2,3-6,7-10,11-14,15-18,＞18 years old).The CTDIvol and DLP values were randomly sampled using MATLAB platform-based dicom data software.The SSDE and water equivalent diameter were also calculated according to the AAPM 220 Report.The differences in radiation doses from lung CT scaning between children and adult patients were analysed.Results The CTDIvol values for all age groups were significantly lower than the SSDE values.The differences were statistically significant (t =-36.36,-32.83,-30.36,-28.74,-23.89,P＜0.05).The SSDE values were 137％,94％,79％,57％ and 42％ higher than the CTDIvol values,respectively.The CTDIvol values for the adult group were also lower than the SSDE values,and the difference was statistically significant (t=-21.92,P＜0.05),and the SSDE value was about 41％ higher than the CTDIvol value.With the increased age,CTDIvol value,DLP value,Dw value and SSDE value for children of all age groups gradually increased and were significantly smaller than those for the adult group.The difference was statistically significant (F=63.39,203.28,89.27,103.44,P＜0.05).The conversion coefficient f for all age groups decreased significantly with age,which was significantly higher than that for the adult group,and the difference was statistically significant (F =109.83,P ＜ 0.05).Conclusions In lung CT scanning,the CTDIvol value significantly underestimated the radiation doses to children as compared to adults.CTDIvol values are more easily underestimated for younger patients.The SSDE method allows for more accurate reflection of the radiation doses to different patients,taking into account differences in the examined patient size.

Características de neumonía por Covid-19 en tc de tórax: revisión de la literatura actual / Features of Covid-19 pneumonia in chest ct: current literature review

INTRODUCCIÓN: Desde diciembre de 2019 la neumonía por SARS-CoV-2 ha experimentado un fuerte avance presentando a la fecha más de nueve millones de casos a nivel mundial. El objetivo de esta revisión es describir las principales características de la neumonía por COVID-19 en la tomografía computada (TC) de tórax en pacientes adultos. MATERIALES Y MÉTODOS: Se buscaron en PubMed artículos que se centraran en las características de la infección por COVID-19 en la tomografía computada de tórax en adultos durante el último año, en inglés y español. Las palabras clave fueron: "COVID-19", "chest CT manifestations" "chest CT findings" y "chest CT features", excluyendo estudios en población pediátrica, cartas al editor y casos clínicos. Se examinaron títulos y resúmenes de artículos obtenidos y se descartaron estudios no atingentes al objetivo de la investigación. RESULTADOS: Se obtuvieron 21 artículos. Una gran variedad de hallazgos en la TC de tórax han sido reportados en los distintos artículos revisados, siendo los más característicos las opacidades en "vidrio esmerilado" de predominio periférico y bilateral; con o sin consolidaciones, que además pueden asociarse a engrosamiento septal interlobulillar, conformando un patrón en empedrado (crazy paving) y a engrosamiento perivascular. Menos frecuentes son el compromiso central, la presencia de nódulos, quistes y derrame pleural. CONCLUSIONES: La tomografía computada de tórax tiene un papel fundamental en la evaluación y manejo de los pacientes con COVID-19, con un evidente rol diagnóstico en ciertas situaciones. El conocimiento de sus características imagenológicas resulta de suma importancia en el contexto actual

Introduction: The new Coronavirus Disease 2019 (COVID-19) has become an unprecedented global health emergency. The World Health Organization estimates global mortality from COVID-19 at 3.4%, however it will be higher in patients with comorbidities such as Cancer (5.6%), High Blood Pressure (6.0%), Chronic respiratory disease (6.3%), Diabetes (7.3%) and Cardiovascular Disease (10.5%). These diseases are among the most prevalent in the world, for this reason we pretend to synthesize their pathophysiology and role in COVID-19, in order to identify effective measures that decrease morbidity and mortality in these high risk groups. Methodology: A review was performed using the databases MEDLINE, PubMed and Google Scholar. Original articles and bibliographic review articles were considered, prioritizing the articles published this year. Results: SARS-CoV-2 uses the enzyme ACE2 as a functional receptor, which allows its entry into the host cell. Eventually, regulates its expression downward, with Angiotensin-II prevailing with its profibrotic, prothrombotic and proinflammatory functions, leading to the deleterious effects of the disease. Chronic non-transmissible diseases (NTCD) would have baseline alteration in ACE2 levels, dysregulation of the immune system, endothelial dysfunction, and chronic inflammation, which would be associated with increased susceptibility and severity in COVID-19. Conclusion: Prevention and identification of risk patients remains the main measure against COVID-19. It is necessary to emphasize efforts in the prevention of NTCD and the promotion of healthy lifestyles. The negative effects of prolonged confinement and suspension of health care services must be considered.

Comparison of Radiological and Histological Findings of Lung Parenchyma in Patients with Antineutrophil Cytoplasmic Antibody-Associated Vasculitis

PURPOSE: The present study investigated chest computed tomography (CT) patterns and lung histological features, as well as the consistency between radiological and histological features among patients with microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic GPA (EGPA). MATERIALS AND METHODS: The medical records of 74 antineutrophil cytoplasmic antibody-associated vasculitis (AAV) patients with radiological lung parenchymal lesions were reviewed along with the histological results for 28 of them. Chest CT patterns were divided according 12 items mostly suggested by radiologists and histological features were divided according to necrotising granuloma, necrotising vasculitis, eosinophilic infiltration, and hemosiderin laden macrophages as defined by a pathologist. RESULTS: The mean age was 57.1 years (22 men). The most common clinical manifestation other than lung manifestation was renal manifestation (62.2%), and the most common chest CT pattern was lung involvement of vasculitis (35.1%). In MPA patients, the major histological features were hemosiderin-laden macrophages in the alveolar space and vasculitis. In GPA patients, the major histological features were necrotizing vasculitis and necrotizing granuloma, while in EGPA patients, the major histological feature was only necrotising vasculitis. The consistency rate in GPA patients was the highest (100%), followed by that in MPA patients (66.7%) and EGPA patients (50.0%). CONCLUSION: When lung involvement of AAV is suspected on chest CT, lung biopsy should be recommended for the proper classification of AAV, due to the discordance rate between radiological and histological findings in MPA and EGPA patients, but not GPA patients.

Quantitative Image Quality and Histogram-Based Evaluations of an Iterative Reconstruction Algorithm at Low-to-Ultralow Radiation Dose Levels: A Phantom Study in Chest CT

OBJECTIVE: To describe the quantitative image quality and histogram-based evaluation of an iterative reconstruction (IR) algorithm in chest computed tomography (CT) scans at low-to-ultralow CT radiation dose levels. MATERIALS AND METHODS: In an adult anthropomorphic phantom, chest CT scans were performed with 128-section dual-source CT at 70, 80, 100, 120, and 140 kVp, and the reference (3.4 mGy in volume CT Dose Index [CTDIvol]), 30%-, 60%-, and 90%-reduced radiation dose levels (2.4, 1.4, and 0.3 mGy). The CT images were reconstructed by using filtered back projection (FBP) algorithms and IR algorithm with strengths 1, 3, and 5. Image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were statistically compared between different dose levels, tube voltages, and reconstruction algorithms. Moreover, histograms of subtraction images before and after standardization in x- and y-axes were visually compared. RESULTS: Compared with FBP images, IR images with strengths 1, 3, and 5 demonstrated image noise reduction up to 49.1%, SNR increase up to 100.7%, and CNR increase up to 67.3%. Noteworthy image quality degradations on IR images including a 184.9% increase in image noise, 63.0% decrease in SNR, and 51.3% decrease in CNR, and were shown between 60% and 90% reduced levels of radiation dose (p < 0.0001). Subtraction histograms between FBP and IR images showed progressively increased dispersion with increased IR strength and increased dose reduction. After standardization, the histograms appeared deviated and ragged between FBP images and IR images with strength 3 or 5, but almost normally-distributed between FBP images and IR images with strength 1. CONCLUSION: The IR algorithm may be used to save radiation doses without substantial image quality degradation in chest CT scanning of the adult anthropomorphic phantom, down to approximately 1.4 mGy in CTDIvol (60% reduced dose).

Performance of Half-dose Chest Computed Tomography in Lung Malignancy Using an Iterative Reconstruction Technique / 고신대학교의과대학학술지

OBJECTIVES: The purpose of this study was to evaluate the performance of half-dose chest CT using an iterative reconstruction technique in patients with lung malignancies. METHODS: The Dual-source CT scans were obtained and half-dose datasets were reconstructed with 5 different strengths in 38 adults with lung malignancies. Two radiologists graded subjective image quality; noise, contrast and sharpness at the central/peripheral lung, mediastinum and chest wall of the reconstructed half-dose images, compared with those of standard-dose images, using a three-point scale. A lesion assessment; lesion conspicuity and diagnostic confidence, was also performed. The quantitative image noises; contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR) were measured and compared with those of standard-dose images. RESULTS: The subjective image noise in the half-dose images was less than that of the standard-dose images. The contrast in strengths 2 to 5 was superior, the sharpness of the lung parenchyma in strengths 3 to 5 was inferior, and the CNR/SNR in all strengths were higher than those of standard-dose images (P < 0.05). The improvement of subjective image noise and contrast, the decrease in sharpness, were correlated with strength level (P < 0.05). The lesion conspicuity in half-dose images of strengths 4 and 5 was decreased. The diagnostic confidence of the half-dose images of all strengths was comparable to that of the standard-dose images (P < 0.05). CONCLUSIONS: Half-dose chest CT images using an iterative reconstruction technique show decreased image noise, increased contrast, and diagnostic confidence comparable to standard-dose images. Images reconstructed with strength 2 and 3 appear to be the optimal choice in clinical practice.

Correlation of Sterno-Aortic distance with FEV1/ FVC and FEV1 in patients with COPD

Background@#Chronic obstructive pulmonary disease (COPD) is defined by the Global Initiative for Chronic Obstructive Lung Disease as " a disease state characterize by airflow limitation that is not fully reversible". Several qualitative and quantitative CT parameters have been studied in diagnosing patients with COPD. The clinical application of CT scan in quantitative assessment of the morphologic features of airways in patients with COPD has been subjects of numerous investigations. However, studies on sterno-aortic distance as a parameter in assessing morphologic feature of COPD in CT scan has been rare. Hence, this study aims to find a correlation of sterno-aortic distance with pulmonary function test in patients with COPD. @*Methods@#Eighty-one patients diagnosed with COPD who underwent chest CT scan and PFT within the period of one year were included. Sterno-aortic distance were measured and correlated with PFT results and severity of COPD. @*Results@#Most patients enrolled were males with average age of 64 ‡ 11years old. Most of these patients are categorized as mild COPD with 38 % and severe COPD with 38% of the total population. Patients classified as moderate COPD comprise 24 % of the total population. There is significant weak inverse correlation between sterno-aortic distance and PFT results, FEV1 (r = -0.419, p < 0.001) and FEV1/FVC(r = -0.322, p value of 0.003). There is a significant correlation derived between stern aortic distance and severity of COPD (ho = 0.88, p-value of <0.001). @*Conclusions@#Sterno-aortic distance is a valuable parameter in patients with COPD as well as its severity.

The imaging features of Mycoplasma pneumoniae pneumonia in children / 中华实用儿科临床杂志

Mycoplasma pneumoniae is a common pathogen of community acquired pneumonia in children.The imaging manifestations of Mycoplasma pneumoniae pneumonia in children varied,the understanding of the causes in clinical pediatrician is not sufficient.The common imaging appearances of chest X-ray,chest CT and chest magnetic resonance imaging (MRI) in children with Mycoplasma pneumoniae pneumonia attributed to age,course,clinical manifestations and severity of illness were summarized in this review.