The Diagnostic Accuracy of the Hounsfield Unit Value in Pulmonary Embolism.

Objective: Pulmonary embolism (PE) a vascular disease. Computed tomography pulmonary angiography (CTPA) is the radiological imaging technique used to diagnose PE. In this study, we aimed to demonstrate the diagnostic accuracy of Hounsfield Unit (HU) value for PE based on the hypothesis that acute thrombosis causes an increase in HU value on computed tomography (CT). Methods: This research was as a single-center, retrospective study. Patients presenting to the emergency department (ED) diagnosed with PE on CTPA were enrolled as the study group. In addition, patients admitted to the same emergency department who were not diagnosed with PE and had non-contrast CT scans were included as the control group. A receiver operating curve (ROC) was produced to the diagnostic accuracy of HU values in predicting PE. Results: The study population (N=74) consisted of a study group (N=46) and a control group (N=28). The sensitivity and specificity of HU value for predicting PE on thoracic CT were found 61.5% and 96.4% at a value of 54.8 (Area Under the Curve (AUC):0.690) for right main pulmonary artery; 65.0% and 96.4% at a value of 55.9 (AUC:0.736) for left main pulmonary artery; 44.4% and 96.4% at a value of 62.7 (AUC:0.615) for right interlobar artery; and 60.0% and 92.9% at a value of 56.7 (AUC:0.736) for left interlobar artery. Conclusion: HU values may exhibit high diagnostic specificity on CT, for thrombi up to the interlobar level. An HU value exceeding 54.8 up to the interlobar level may raise suspicion of the presence of PE.

The Effects of Vaccines on the Sequelae Rates of Recurrent Infections and the Severity of Pulmonary COVID-19 Infection by Imaging.

Although vaccines have been shown to reduce the number of COVID-19 infection cases significantly, vaccine-related reactions, long COVID-19 syndrome, and COVID-19 infection following vaccination continue to be a burden on healthcare services and warrant further scientific research. The purpose of this study was to research the severity of pulmonary COVID-19 infection following vaccination and the sequelae rates of recurrent infections in vaccinated cases by imaging. Patients who underwent follow-up CTs at 1 month, 3 months, and 6 months in our hospital with a diagnosis of COVID-19 were scanned retrospectively. Furthermore, all essential information was gathered from patients' immunization records. The major findings of our study were: (1) sequelae were frequently observed in unvaccinated cases; (2) the correlation between vaccination status and the severity of sequelae was significant; (3) there was not any significant relationship between the vaccine type and the severity of sequelae; and (4) hematocrit, hemoglobin, and lymphocyte parameters may be used as predictors of sequelae rates. COVID-19 infection, although reduced in prevalence following the development of vaccines, still remains a public health concern because of reinfection. Vaccination not only appears to protect against primary infection, but also seems to reduce reinfection and sequalae rates following reinfection.

Evaluation of thorax computed tomographic findings in COVID-19 variant cases.

BACKGROUND: Because of genetic mutations occurring during viral replication, new SARS-CoV-2 variants will continue to emerge. Throughout the COVID-19 pandemic, thorax computed tomographic (CT) findings have played a crucial role in the diagnosis and follow-up of patients with COVID-19. In this study, we compared the thorax CT findings of patients infected with SARS-CoV-2 variants (variant group) with those of patients infected with the non-variant strain (non-variant group) to assess if thorax CT findings may be utilized to discriminate between the groups. Furthermore, we compared demographic and laboratory data between the groups. METHODS: The study comprised a total of 77 patients who presented to our hospital with a preliminary diagnosis of COVID-19 based on clinical symptoms, a positive oropharyngeal/nasopharyngeal swab RT-PCR testing, and thorax CT examinations. Patients' laboratory and demographic features as well as thorax CT findings were retrospectively evaluated, and the results were grouped according to RT-PCR results. RESULTS: There were 42 patients in the non-variant group and 35 patients in the variant group. The average age of patients infected with the non-variant strain, alpha variant, and gamma variant was 63.52 ± 14.87 years, 54.86 ± 14.31 years, and 59.4 ± 17.79 years, respectively. The average age of the variant group was significantly lower than that of the non-variant group. There was no significant difference in thorax CT findings between the groups, and consolidation, ground glass densities, and cobblestone pattern in the bilateral lower lobes and peripheral areas were the most common thorax CT findings in both the groups. CONCLUSION: There is no significant difference in thorax CT findings between the variant and non-variant groups. Therefore, clinical and laboratory characteristics should take precedence over thorax CT findings for distinguishing between patients infected with SARS-CoV-2 variants and the non-variant strain.

Diagnostic performance of thorax CT in mildly symptomatic COVID-19 patients: The importance of atypical CT findings.

OBJECTIVE: Computed tomography of the thorax (Thorax CT) is frequently used to diagnose viral pneumonia in moderate to severe COVID-19 patients, but its diagnostic performance in mildly symptomatic COVID-19 patients is still unclear. Assessing the diagnostic performance of thorax CT in mildly symptomatic COVID-19 patients was the purpose of our study. METHODS: Mildly symptomatic and clinically stable, suspected COVID-19 patients scanned with Thorax CTs between March 11, 2020, and April 13, 2020, were included in this study. The sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values, and the respective accuracies were calculated for diagnostic purposes. RESULTS: Among the 1119 patients enrolled in our study, abnormal thorax CT scans were 527 out of which 363/527 (68.9%) had typical CT features for COVID-19. According to analysis of typical COVID findings, sensitivity, specificity, positive predictive values, negative predictive value, and the accuracy of Thorax CTs with were 51.45%, 86.07%, 78.24%, 64.55%, and 68.99%, respectively. When typical CT findings and atypical CT findings were combined for the statistical analysis, the sensitivity, specificity, and accuracy observed 68.84%, 74%, and 71.49%. CONCLUSION: Diagnosing pneumonia can be challenging in mildly symptomatic COVID-19 patients since the Reverse Transcription Polymerase Chain Reaction test results, when compared with symptoms are not always evident. According to our study, thorax CT sensitivity was higher when atypical COVID-19 CT findings were included compared to those with typical COVID-19 CT findings alone. Our study which included the largest number of patients among all other similar studies indicates that not only typical but also atypical CT findings should be considered for an accured diagnosis of COVID-19 pneumonia.

Chest computed tomographic findings of patients with COVID-19-related pneumonia.

BACKGROUND: In December 2019, pneumonia cases of unknown cause were announced in Wuhan, China. The causative agent of pneumonia was identified as coronavirus 2 (SARS-CoV-2), and the disease was named coronavirus disease 2019 (COVID-19). PURPOSE: To evaluate the usefulness of computed thoracic tomography (CT) and postero anterior (PA) thoracic radiography in patients with COVID-19. MATERIAL AND METHODS: Between March and June 2020, the patients who arrived at our hospital with suspicion of COVID-19 were retrospectively analyzed. Thorax CT findings of the 281 patients (142 females and 139 males; age range 3-91 years) with positive PCR tests were evaluated. Lesions in the lung parenchyma were examined according to their number, localization, and distribution. PA chest radiograms were classified into two groups, positive and negative for the lung parenchymal lesions. RESULTS: Of the total 281 patients with PCR-positive COVID-19, CT examinations were normal in 107 (38.1%), and positive CT findings for pneumonia were found in 174 patients (61.9%). Bilateral involvement was observed in 100 (57.5%) of the 174 patients with positive CT findings, and unilateral involvement was observed in 74 (42.5%) of them. According to the localization of the lesions, peripheral subpleural distribution occurred in 160 of the 174 patients (91.9). The most common lesion was the ground glass opacities (GGO). In 77 of 281 PCR-positive patients (27.4), pulmonary lesions were found on PA chest radiograms. CONCLUSION: The presence of bilateral posterior subpleural GGO, nodule, and consolidation in thoracic CT are significant in terms of COVID-19 pneumonia.

Evaluation of the relation between cardiac biomarkers and thorax computed tomography findings in COVID-19 patients.

Background: Troponin levels may be elevated in COVID-19 infection. The aim of this study was to the explore relation between troponin levels and COVID-19 severity. Materials, methods & Results: One hundred and forty consecutive patients with COVID-19 pneumonia were included. Diagnosis of COVID-19 pneumonia was based on positive chest computed tomography (CT) findings. Quantitative PCR test was performed in all patients. Only 74 patients were quantitative PCR-positive. Twenty four patients had severe CT findings and 27 patients had progressive disease. These patients had significantly lower albumin and higher ferritin, D-dimer, lactate dehydrogenase, C-reactive protein, and high-sensitivity cardiac troponin I (hs-cTnI). Conclusion: COVID-19 patients with severe CT findings and progressive disease had higher hs-cTnI levels suggesting the use of hs-cTnI in risk stratification.

Evidence of Pulmonary Hypertension after SARS-CoV-2 Infection in Subjects without Previous Significant Cardiovascular Pathology.

BACKGROUND: Coronavirus (Covid-19) infection represents a serious medical condition, often associated with cardiovascular complications, pulmonary hypertension (PH), and right ventricle dysfunction (RVD). The aim of this study is to show, by means of transthoracic echocardiography (TTE), the presence of an increased estimated systolic pressure in the pulmonary artery (esPAP) and altered right ventricular global longitudinal strain (RV-GLS) in patients without history of PH. METHODS: In a group of 91 patients, aged under 55 years, hospitalized for a moderate Covid-19 infection, a thorough cardiologic and TTE examination were performed two months after discharge. Their initial thorax computer-tomography (TCT) images and laboratory data were accessed from the electronic data base of the hospital. RESULTS: We observed an increased prevalence of PH (7.69%) and RVD (10.28%), significantly correlated with the initial levels of the TCT score and inflammatory factors (p ˂ 0.001), but borderline changes were observed in more patients. Multivariate regression analysis showed that these factors and RV-GLS explain 89.5% of elevated esPAP. CONCLUSIONS: In COVID-19 infection, PH and RVD are common complications, being encountered after the recovery even in moderate cases. It appears to be a connection between their severity and the extent of the initial pulmonary injury and of the inflammatory response.

LGAN: Lung segmentation in CT scans using generative adversarial network.

Lung segmentation in Computerized Tomography (CT) images plays an important role in various lung disease diagnosis. Most of the current lung segmentation approaches are performed through a series of procedures with manually empirical parameter adjustments in each step. Pursuing an automatic segmentation method with fewer steps, we propose a novel deep learning Generative Adversarial Network (GAN)-based lung segmentation schema, which we denote as LGAN. The proposed schema can be generalized to different kinds of neural networks for lung segmentation in CT images. We evaluated the proposed LGAN schema on datasets including Lung Image Database Consortium image collection (LIDC-IDRI) and Quantitative Imaging Network (QIN) collection with two metrics: segmentation quality and shape similarity. Also, we compared our work with current state-of-the-art methods. The experimental results demonstrated that the proposed LGAN schema can be used as a promising tool for automatic lung segmentation due to its simplified procedure as well as its improved performance and efficiency.

Report of Two COVID-19 ARDS (CARDS) Cases Who Survived without Intubation and Mechanical Ventilation.

The most severe clinical feature of COVID-19 is Acute Respiratory Distress Syndrome (ARDS) which requires intubation and mechanical ventilation and it occurs in approximately 2.3% of cases. About 94% of of these cases end in death. This case series report two confirmed COVID-19 patients who had met criteria of intubation and mechanical ventilation, but not performed to them. Both patients experienced clinical improvement and recovery. Probably this is due to differences of COVID-19 ARDS (CARDS) with typical or classic ARDS.  CARDS is divided into two phenotypes of type L (Low Elastance) and type H (High Elastance). These different phenotypic also distinguish subsequent pathophysiology and clinical management. These phenotype can be differentiate by chest CT scan. This case series emphasizes the importance of understanding this phenotype so that clinicians can provide more appropriate treatment management and also availability of CT scans in health facilities that manage COVID -19.

The usual course of thorax CT findings of COVID-19 infection and when to perform control thorax CT scan

COVID-19 infection, a highly contagious disease caused by the SARS-CoV virus, and the World Health Organization declared this increasingly spreading disease as a global public health emergency (pandemic). In the diagnosis of COVID-19, the polymerase chain reaction (RT-PCR) is considered as the reference standard test. In the early stages, thorax CT findings could be present even before the onset of symptoms, thorax CT has quite high sensitivity in COVID-19 patients with false negative RT-PCR results, and it has a great importance not only in diagnosis but also in follow up. We think that it might be beneficial for our radiologist colleagues in the early diagnosis of the imaging features of this disease, by sharing the experiences we have gained by evaluating the typical and relatively atypical CT findings regarding the natural course of the tomographic findings of COVID-19 and when to control CT.

Accuracy of registration algorithms in subtraction CT of the lungs: A digital phantom study.

PURPOSE: The purpose of this study was to assess, using an anthropomorphic digital phantom, the accuracy of algorithms in registering precontrast and contrast-enhanced computed tomography (CT) chest images for generation of iodine maps of the pulmonary parenchyma via temporal subtraction. MATERIALS AND METHODS: The XCAT phantom, with enhanced airway and pulmonary vessel structures, was used to simulate precontrast and contrast-enhanced chest images at various inspiration levels and added CT simulation for realistic system noise. Differences in diaphragm position were varied between 0 and 20 mm, with the maximum chosen to exceed the 95th percentile found in a dataset of 100 clinical subtraction CTs. In addition, the influence of whole body movement, degree of iodine enhancement, beam hardening artifacts, presence of nodules and perfusion defects in the pulmonary parenchyma, and variation in noise on the registration were also investigated. Registration was performed using three lung registration algorithms - a commercial (algorithm A) and a prototype (algorithm B) version from Canon Medical Systems and an algorithm from the MEVIS Fraunhofer institute (algorithm C). For each algorithm, we calculated the voxel-by-voxel difference between the true deformation and the algorithm-estimated deformation in the lungs. RESULTS: The median absolute residual error for all three algorithms was smaller than the voxel size (1.0 × 1.0 × 1.0 mm3 ) for up to an 8 mm diaphragm difference, which is the average difference in diaphragm levels found clinically, and increased with increasing difference in diaphragm position. At 20 mm diaphragm displacement, the median absolute residual error after registration was 0.85 mm (interquartile range, 0.51-1.47 mm) for algorithm A, 0.82 mm (0.50-1.40 mm) for algorithm B, and 0.91 mm (0.54-1.52 mm) for algorithm C. The largest errors were seen in the paracardiac regions and close to the diaphragm. The impact of all other evaluated conditions on the residual error varied, resulting in an increase in the median residual error lower than 0.1 mm for all algorithms, except in the case of whole body displacements for algorithm B, and with increased noise for algorithm C. CONCLUSION: Motion correction software can compensate for respiratory and cardiac motion with a median residual error below 1 mm, which was smaller than the voxel size, with small differences among the tested registration algorithms for different conditions. Perfusion defects above 50 mm will be visible with the commercially available subtraction CT software, even in poorly registered areas, where the median residual error in that area was 7.7 mm.

Volume Measurement in the Diagnosis of Mounier Kuhn Syndrome and an Unknown Accompanying Pathology: Pulmonary Artery Enlargement.

BACKGROUND: Mounier Kuhn Syndrome (MKS) is a rare congenital anomaly characterized by abnormal dilatation of the trachea and main bronchi. The aim of this study is to discuss tracheal volume measurement in MKS, and the pathologies accompanying MKS, especially pulmonary artery enlargement. MATERIALS AND METHODS: 38 patients, 18 of whom were diagnosed with MKS and 20 as control group, were included in the study. Trachea volume and pulmonary artery diameter were measured through thorax-computed tomography (CT) images of the patients. Accompanying pathologies were recorded. RESULTS: In the measurements done through the CT scans, the trachea volume was found to be 25.45 cm3 in the control group and 44.17 cm3 in the patient group. The most frequent accompanying pathologies were tracheal diverticulum, bronchiectasis and pulmonary artery enlargement. CONCLUSION: In patients with MKS, there is a significant difference in volume calculation as in trachea diameter. Though bronchiectasis and tracheal diverticulum are known as pathologies most frequently accompanying MKS, to the knowledge of the researchers, pulmonary artery enlargement due to the increase in pulmonary truncus diameter was first emphasized in this article.

Perfil epidemiológico de pacientes com nódulos pulmonares em acompanhamento ambulatorial no período de 2013 a 2015 / Epidemiological profile of patients with pulmonary nodules in clinic follow-up in the period from 2013 to 2015

Este artigo teve como objetivo conhecer o perfil epidemiológico dos pacientes com nódulos pulmonares descobertos de forma acidental e seu desfecho durante o acompanhamento no ambulatório de pneumologia de Criciúma/SC entre os anos de 2013 a 2015. Realizou-se um estudo observacional, longitudinal, retrospectivo, de abordagem quantitativa, com coleta de dados de 250 prontuários de pacientes com diagnóstico de nódulo pulmonar ao acaso. As características clínicas estudadas foram: gênero, idade, tabagismo, carga tabágica e o exame de diagnóstico. As características radiográficas avaliadas em relação ao nódulo foram: presença de margens espiculadas, tamanho nodular, localização anatômica e, posteriormente, os nódulos foram classificados em: provavelmente benigno, maligno ou indeterminado. Como resultado, percebeu-se que 58,8%dos casos de nódulo pulmonar foram observados em mulheres, sendo a faixa etária mais comum, independente de gênero, entre 51-70 anos. Em 60,6% dos pacientes, o raio-X de tórax foi o exame que detectou esses nódulos. Observou-se, também, que 60,8% dos nódulos foram classificados como provavelmente benigno e 44,8% dos nódulos localizaram-se em lobos superiores. Houve associação significativa entre malignidade do nódulo e tamanho do mesmo (p = 0,001).Portanto, conclui-se que a prevalência dos nódulos incidentais foi maior na faixa etária de 51-70 anos, sendo que as mulheres alcançaram porcentagem 17,6% superior ao sexo masculino. Verificou-se predomínio da distribuição dos nódulos em lobos superiores e da categorização dos nódulos como provavelmente benignos. Além disso, significância estatística foi constatada em relação aos maiores tamanhos nodulares e provável desfecho maligno (p = 0,001).

This article had as objective to know the epidemiological profile of patients with accidentally discovered pulmonary nodules and their outcome during the follow-up in the Criciúma/SC pneumology clinic between 2013 and 2015. An observational, longitudinal, retrospective study, with quantitative approach was performed with data collection of 250 medical records of patients with diagnosis of incidental pulmonary nodules. The clinical characteristics studied were: gender, age, smoking, smoking load and diagnostic examination. The radiographic characteristics evaluated in relation to the nodule were: presence of spiculated margins, nodular size, anatomical location and, later, the nodules were classified in: probably benign, malignant or undetermined. As a result, it was observed that 58,8% of the cases of pulmonary nodule were observed in women, being the most common age group, independent of gender, between 51-70 years. In 60,6% of the patients, the chest xray was the test that detected theses nodules. It was also observed that 60,8% of the nodules were classified as probably benign and 44,8% of the nodules were located in upper lobes. There was a significant association between nodule malignancy and size of the nodule (p = 0.001). Therefore, it is concluded that the prevalence of incidental nodules was higher in the age group of 51-70 years, and women reached percentage 17.6% higher than male sex. There was a predominance of nodal distribution in upper lobes and the categorization of nodules as probably benign. Furthermore, statistical significance was observed in relation to the larger nodular sizes and probable malignant outcome (p = 0.001).

The diagnosis of pulmonary embolism without contrastis not always Challenging: be aware of hyperdense lumen sign.

Acute pulmonary embolism (PE) diagnosis is a challenging task, despite the advanced diagnostic methods for both clinicians and radiologists. Awareness of the "hyperdense lumen sign" in patients obtained un-enhanced computarized tomography (CT) of chest mayhelp to establish an acute PE diagnosis, especially in clinically non suspected PE patients. A 78-year-old woman was brought to our emergency department (ED) with an aphasia complaint. The patient's dizziness improved in ED. Neurological examination returned to base line status but sinus tachycardia and low saturation value on room air were continuing. Un-enhanced CT of the chest demonstrates hyperdense material within the right main pulmonary artery. Contrast-enhanced CTPA demonstrated hypodense filling defect within the rigth main pulmonary artery consistent with PE. Independent of the patient's complaint, the measurement of all vital signs is important especially in elderly patients. Emergency physicians have to be aware of that the "hyperdense lumen sign" may point out PE and should be prevented from delayed recognition.

Prospective intra-individual comparison of standard dose versus reduced-dose thoracic CT using hybrid and pure iterative reconstruction in a follow-up cohort of pulmonary nodules-Effect of detectability of pulmonary nodules with lowering dose based on nodule size, type and body mass index.

OBJECTIVES: To determine the diagnostic accuracy of lung nodule detection in thoracic CT using 2 reduced dose protocols comparing 3 available CT reconstruction algorithms (filtered back projection-FBP, adaptive statistical reconstruction-ASIR and model-based iterative reconstruction-MBIR) in a western population. MATERIALS AND METHODS: A prospective single-center study recruited 98 patients with written consent. Standard dose (STD) thoracic CT followed by 2 reduced-dose protocols using automatic tube current modulation (RD1) and fixed tube current (RD2) were performed and reconstructed with FBP, ASIR and MBIR with subsequent diagnostic accuracy analysis for nodule detection. RESULTS: 108 solid nodules, 47 subsolid nodules and 89 purely calcified nodules were analyzed. RD1 was superior to RD2 for assessment of solid nodules ≤4mm, and subsolid nodules ≤5mm (p<0.05). Deterioration of RD2 is correlated to patient's body mass index and least affected by MBIR. For solid nodules ≤4mm, MBIR area under curve (AUC) for RD1 was 0.935/0.913 and AUC for RD2 was 0.739/0.739, for rater 1/rater2 respectively. For subsolid nodules ≤5mm, MBIR AUC for RD1 was 0.971/0.986 and AUC for RD2 was 0.914/0.914, for rater 1/rater2 respectively. For calcified nodules excellent detection accuracy was maintained regardless of reconstruction algorithms with AUC >0.97 for both readers across all dose and reconstruction algorithms. CONCLUSIONS: Diagnostic performance of lung nodule is affected by nodule size, protocol, reconstruction algorithm and patient's body habitus. The protocol in this study showed that RD1 was superior to RD2 for assessment of solid nodules ≤4mm, and subsolid nodules ≤5mm and deterioration of RD2 is related to patient's body mass index.

Thorax CT findings in patients with Crimean-Congo hemorrhagic fever (CCHF).

PURPOSE: Crimean-Congo hemorrhagic fever (CCHF) is a zoonotic viral disease with high mortality. The agent causing CCHF is a Nairovirus. The virus is typically transmitted to humans through tick bites. CCHF is a life-threatening disease observed endemically over a wide geographical regions in the world and a little known about pulmonary findings in CCHF patients. METHODS: The patients that were admitted and diagnosed with CCHF between April 2010 and September 2015 were examined. Patients' medical records were then evaluated retrospectively. Patients who underwent thorax CT evaluation based on the clinical findings at the time of admission and/or during the hospital stay were included in the study. Patients' laboratory test results and thorax CT findings for respiratory assessment along with demographic characteristics. RESULTS: Forty patients diagnosed with CCHF that underwent thorax CT based on their indications were included in the study. Twenty-seven patients (62.5 %) were male with a mean age of 55.22 ± 19.84 years. According to these results, the three most common thorax CT findings were parenchymal infiltration [32 patients (80 %)], pleural effusion [31 patients (77.5 %)], and alveolar infiltration [28 patients (70 %)]. Moreover, we determined that the most frequently seen radiological findings often occurred bilaterally. CONCLUSIONS: There is still not enough information regarding this life-threatening disease. We also would like to emphasize that both direct radiography and thorax CT are highly successful in detecting frequently encountered radiological findings such as pleural effusion, alveolar hemorrhage, and parenchymal infiltration that indicate pulmonary involvement.

Thoracic non-osseous lesions in cancer patients detected in low-dose CT images acquired as part of skeletal SPECT/CT examinations.

AIM: Hybrid single-photon emission tomographic (SPECT) and X-ray computed tomography (CT) systems are increasingly used in oncologic imaging. With SPECT/CT not only the thoracic spine but also the surrounding soft tissue needs to be evaluated for pathological findings. The purpose of this study was to assess the prevalence of non-osseous findings detectable on low-dose CT datasets from patients studied by thoracic 99mTc-dicarboxypropane diphosphonate (DPD)-SPECT/CT. PATIENTS, METHODS: 119 consecutive oncologic patients (81 breast cancer, 38 with other cancer) who underwent DPD-SPECT CT of the thoracic region were included in this study. Non-osseous findings on CT were classified as either probably benign or suspicious. Suspicious findings were correlated with retrievable previous imaging and if performed with follow up imaging (MRI, CT with contrast medium, Ultrasound) or biopsy results. RESULTS: In 80/119 (67%) patients no imaging was performed before SPECT/CT. Only 7/119 subjects (6%) had no other lesions than bone lesions. In 101/119 (85%) patients lesions found on SPECT/CT images were rated as benign and in 65/119 (55%) patients as suspicious. In 8/119 (7%) patients with previously unknown suspicious lesions on SPECT/CT images suspicious findings were confirmed by biopsy. CONCLUSION: 7% of patients referred to SPECT/CT of the thoracic spine for staging of malignant disease had previously unknown suspicious non-osseous lesions detectable on the low-dose CT images which were confirmed by biopsy. This could be especially relevant for cancer entities like breast and prostate, in which no thorax-CT is routinely intended for staging.

Redistributed regional ventilation after the administration of a bronchodilator demonstrated on xenon-inhaled dual-energy CT in a patient with asthma.

We report here on the redistributed regional ventilation abnormalities after the administration of a bronchodilator and as seen on xenon-inhaled dual-energy CT in a patient with asthma. The improved ventilation seen in the right lower lobe and the decreased ventilation seen in the right middle lobe after the administration of a bronchodilator on xenon-inhaled dual-energy CT could explain a positive bronchodilator response on a pulmonary function test. These changes may reflect the heterogeneity of the airway responsiveness to a bronchodilator in patients with asthma.

Redistributed Regional Ventilation after the Administration of a Bronchodilator Demonstrated on Xenon-Inhaled Dual-Energy CT in a Patient with Asthma

We report here on the redistributed regional ventilation abnormalities after the administration of a bronchodilator and as seen on xenon-inhaled dual-energy CT in a patient with asthma. The improved ventilation seen in the right lower lobe and the decreased ventilation seen in the right middle lobe after the administration of a bronchodilator on xenon-inhaled dual-energy CT could explain a positive bronchodilator response on a pulmonary function test. These changes may reflect the heterogeneity of the airway responsiveness to a bronchodilator in patients with asthma.

Multilocular Thymic Cyst Associated with Mediastinal Teratoma: A Case Report

Multilocular thymic cyst (MTC) has been reported to develop in concert with various mediastinal neoplasms that have intrinsic inflammatory components, such as thymoma, thymic carcinoma, Hodgkin's disease, and seminoma. However, development of mediastinal teratoma without intrinsic inflammation in association with MTC has rarely been reported. Here, we report the findings of a case of MTC associated with mediastinal mature cystic teratoma on computed tomography (CT) with CT-histopathologic correlation.