Pulmonary Computed Tomography Research Articles

Thromboprophylaxis decreases the risk of pulmonary embolism in COVID-19

Aim: Pulmonary embolism caused by micromboli and microthrombuses might be associated with increased mortality and morbidity in Covid-19. Routine thromboprophylaxis application might contribute to clinical recovery by reducing the risk of pulmonary embolism. In this study, the effects of thromboprophylaxis on clinical outcomes were investigated by examining the rates of computed tomographic angiography requests for the differential diagnosis of pulmonary embolism in the patients with Covid-19. 
 Materials and Methods: Patients who underwent computed tomography (CT) between 10 March and 25 May 2020 in our hospital were retrospectively analysed. Patients who received simultaneous PCR tests during CT examination were included in the study. In the follow-up of these patients, rates of pulmonary CT angiography request with the suspicion of pulmonary embolism and it’s were investigated. 
 Results: During the study period, thorax CT was performed in 11142 patients and pulmonary CT angiography was performed in 161 (1.4%) of them. Ninety-nine patients who were performed CT angiography and PCR test during the hospitalization period were included in the study. PCR test was positive in 22% (n = 21) of the patients (22%) and pulmonary embolism was detected in 6 of them (6.3%). PCR test was negative in 74 patients (78%) and 17 (17.9%) had pulmonary embolism.
 Conclusion: Routine thromboprophylaxis contributes to the treatment of Covid-19 by preventing the development of microthrombosis and thrombotic complications in the respiratory system.

Bronchopulmonary dysplasia in extremely premature infant with congenital lobar emphysema: a case report

BackgroundCongenital lobar emphysema (CLE) is a congenital pulmonary cystic disease, characterized by overinflation of the pulmonary lobe and compression of the surrounding areas. Most patients with symptoms need an urgent surgical intervention. Caution and alertness for CLE is required in cases of local emphysema on chest X-ray images of extremely premature infants with bronchopulmonary dysplasia (BPD).Case presentationHere, we report a case of premature infant with 27 + 4 weeks of gestational age who suddenly presented with severe respiratory distress at 60 days after birth. Chest X-ray and computed tomography (CT) indicated emphysema in the middle lobe of the right lung. The diagnosis of CLE was confirmed by histopathological examinations.ConclusionsAlthough extremely premature infants have high-risk factors of bronchopulmonary dysplasia due to their small gestational age, alertness for CLE is necessary if local emphysema is present. Timely pulmonary CT scan and surgical interventions should be performed to avoid the delay of the diagnosis and treatment.

Pattern and Age Distribution of COVID-19 on Pulmonary Computed Tomography.

COVID-19 has emerged recently and has become a global concern. Computed tomography (CT) plays a vital role in the diagnosis. To characterize the pulmonary CT findings and distributions of COVID-19 infection in regard to different age groups. Chest CT scan of 104 symptomatic patients with COVID-19 infection from 7 Iraqi isolation centers were retrospectively analyzed between March 10th to April 5th, 2020. Patients were sub-classified according to their ages into three groups (young adult:20-39 years, middle age:40-59 years, and old age:60-90 years). The most common findings were ground-glass opacities (GGO) (92.3%, followed by consolidation (27.9%), bronchovascular thickening (15.4%), and crazy-paving (12.5%). Less commonly, there were tree-in-bud (6.7%), pulmonary nodules (5.8%), bronchiectasis (3.8%), pleural effusion (1.9%), and cavitation (1%). There were no hallo signs, reversed hallo signs, and mediastinal lymphadenopathy. Pulmonary changes were unilateral in 16.7% and bilateral in 83.3%, central in 14.6%, peripheral in 57.3%, and diffuse (central and peripheral) in 28.1%. Most cases showed multi- lobar changes (70.8%), while the lower lobe was more commonly involved (17.7%) than the middle lobe/lingula (8.3%) and upper lobe (3.1%). In unilateral involvement, changes were more on the right (68.8%) than the left (31.2%) side. Compared with middle and old age groups, young adult patients showed significantly lesser frequency of consolidation (17% vs. 13.3% and 37%), diffuse changes 28.1% (14.2% vs. 35.3% and 40.5%), bilateral disease (71.4% vs. 94.1% and 85.2%), and multi-lobar involvement (51.4% vs. 82.4% and 81.4%) respectively. Bilateral and peripheral GGO were the most frequent findings with the right and lower lobar predilection. The pattern and the distribution of CT changes seem to be age-specific.

Risk factor analysis of pulmonary cement embolism during percutaneous vertebroplasty or kyphoplasty for osteoporotic vertebral compression fractures

ObjectiveThe purpose of this research is to evaluate the risk factors and incidence of pulmonary cement embolism (PCE) during percutaneous vertebroplasty (PVP) or kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs) based on postoperative computed tomography (CT).MethodsA total of 2344 patients who underwent PVP or PKP due to OVCFs in our spine center were analyzed retrospectively. According to the detection of postoperative pulmonary CT, the patients were divided into two groups: pulmonary cement embolism group (PCE group) and non-pulmonary cement embolism group (NPCE group). Demographic data in both groups were compared using the χ2 test for qualitative data and the unpaired t test for quantitative data. Multiple logistic regression analysis was carried out to identify risk factors that were significantly related to the PCE resulting from cement leakage.ResultsPCE was found in 34 patients (1.9% 34/1782) with pulmonary CT examination after operation. There was no statistically significant difference in the parameters such as age, gender, body mass index (BMI), and cement volume in the two groups. Patients with three or more involved vertebrae had a significantly increased risk to suffer from PCE than those with one involved vertebra (p=0.046 OR 2.412 [95% CI 1.017–5.722]). Patients who suffered thoracic fracture had a significantly increased risk to suffer from PCE than those who suffered thoracolumbar fracture (p=0.001 OR 0.241 [95% CI 0.105–0.550]). And significantly increased PCE risk also was observed in thoracic fracture compared with lumbar fracture patients (p=0.028 OR 0.094 [95% CI 0.114–0.779]). The risk of PCE within 2 weeks after fracture was significantly higher than that after 2 weeks of fracture (p=0.000 OR 0.178 [95% CI 0.074–0.429]). Patients who underwent PVP surgery had a significantly increased PCE risk than those who underwent PKP surgery (p=0.001 OR 0.187 [95% CI 0.069–0.509]).ConclusionThe real incidence of PCE is underestimated due to the lack of routine postoperative pulmonary imaging examination. The number of involved vertebrae, fracture location, operation timing, and operation methods are independent risk factors for PCE.

Split-filter dual-energy CT pulmonary angiography for the diagnosis of acute pulmonary embolism: a study on image quality and radiation dose.

Computed tomography (CT) pulmonary angiography is the diagnostic reference standard in suspected pulmonary embolism (PE). Favorable results for dual-energy CT (DECT) images have been reported for this condition. Nowadays, dual-energy data acquisition is feasible with different technical options, including a single-source split-filter approach. Therefore, the aim of this retrospective study was to investigate image quality and radiation dose of thoracic split-filter DECT in comparison to conventional single-energy CT in patients with suspected PE. A total of 110 CT pulmonary angiographies were accomplished either as standard single-energy CT with automatic tube voltage selection (ATVS) (n=58), or as split-filter DECT (n=52). Objective [pulmonary artery CT attenuation, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)] and subjective image quality [four-point Likert scale; three readers (R)] were compared among the two study groups. Size-specific dose estimates (SSDE), dose-length-product (DLP) and volume CT dose index (CTDIvol) were assessed for radiation dose analysis. Split-filter DECT images yielded 67.7% higher SNR (27.0 vs. 16.1; P<0.001) and 61.9% higher CNR (22.5 vs. 13.9; P<0.001) over conventional single-energy images, whereas CT attenuation was significantly lower (344.5 vs. 428.2 HU; P=0.013). Subjective image quality was rated good or excellent in 93.0%/98.3%/77.6% (R1/R2/R3) of the single-energy CT scans, and 84.6%/82.7%/80.8% (R1/R2/R3) of the split-filter DECT scans. SSDE, DLP and CTDIvol were significantly lower for conventional single-energy CT compared to split-filter DECT (all P<0.05), which was associated with 26.7% higher SSDE. In the diagnostic workup of acute PE, the split-filter allows for dual-energy data acquisition from single-source single-layer CT scanners. The existing opportunity to assess pulmonary "perfusion" based on analysis of iodine distribution maps is associated with higher radiation dose in terms of increased SSDE than conventional single-energy CT with ATVS. Moreover, a proportion of up to 3.8% non-diagnostic examinations in the current reference standard test for PE is not negligible.

Accurate and efficient pulmonary CT imaging workflow for COVID-19 patients by the combination of intelligent guided robot and automatic positioning technology

BackgroundThe ongoing coronavirus disease 2019 (COVID-19) pandemic has put radiologists at a higher risk of infection during the computer tomography (CT) examination for the patients. To help settling these problems, we adopted a remote-enabled and automated contactless imaging workflow for CT examination by the combination of intelligent guided robot and automatic positioning technology to reduce the potential exposure of radiologists to 2019 novel coronavirus (2019-nCoV) infection and to increase the examination efficiency, patient scanning accuracy and better image quality in chest CT imaging . MethodsFrom February 10 to April 12, 2020, adult COVID-19 patients underwent chest CT examinations on a CT scanner using the same scan protocol except with the conventional imaging workflow (CW group) or an automatic contactless imaging workflow (AW group) in Wuhan Leishenshan Hospital (China) were retrospectively and prospectively enrolled in this study. The total examination time in two groups was recorded and compared. The patient compliance of breath holding, positioning accuracy, image noise and signal-to-noise ratio (SNR) were assessed by three experienced radiologists and compared between the two groups. ResultsCompared with the CW group, the total positioning time of the AW group was reduced ((118.0 ± 20.0) s vs. (129.0 ± 29.0) s, P = 0.001), the proportion of scanning accuracy was higher (98% vs. 93%), and the lung length had a significant difference ((0.90±1.24) cm vs. (1.16±1.49) cm, P = 0.009). For the lesions located in the pulmonary centrilobular and subpleural regions, the image noise in the AW group was significantly lower than that in the CW group (centrilobular region: (140.4 ± 78.6) HU vs. (153.8 ± 72.7) HU, P = 0.028; subpleural region: (140.6 ± 80.8) HU vs. (159.4 ± 82.7) HU, P = 0.010). For the lesions located in the peripheral, centrilobular and subpleural regions, SNR was significantly higher in the AW group than in the CW group (centrilobular region: 6.6 ± 4.3 vs. 4.9 ± 3.7, P = 0.006; subpleural region: 6.4 ± 4.4 vs. 4.8 ± 4.0, P < 0.001). ConclusionsThe automatic contactless imaging workflow using intelligent guided robot and automatic positioning technology allows for reducing the examination time and improving the patient's compliance of breath holding, positioning accuracy and image quality in chest CT imaging.

Use of Pulmonary Computed Tomography for Evaluating Suspected Stroke-Associated Pneumonia

ObjectivesAccurate and timely diagnosis of pneumonia complicating stroke remains challenging and the diagnostic accuracy of chest X-ray (CXR) in the setting of stroke-associated pneumonia (SAP) is uncertain. The overall objective of this study was to evaluate the use of pulmonary computed tomography (CT) in diagnosis of suspected SAP. Materials and MethodsPatients with acute ischemic stroke (IS) or intracerebral hemorrhage (ICH) were recruited within 24h of clinically suspected SAP and underwent non-contrast pulmonary CT within 48h of antibiotic initiation. CXR and pulmonary CT were reported by two radiologists. Pulmonary CT was used as the reference standard for final diagnosis of SAP. Sensitivity, specificity, positive and negative predictive values (PPV and NPV), and diagnostic odds ratio (OR) for CXR were calculated. Results40 patients (36 IS, 4 ICH) with a median age of 78y (range 44y-90y) and a median National Institute of Health Stroke Scale score of 13 (range 3-31) were included. All patients had at least one CXR and 35/40 patients (88%) underwent pulmonary CT. Changes consistent with pneumonia were present in 15/40 CXRs (38%) and 12/35 pulmonary CTs (34%). 9/35 pulmonary CTs (26%) were reported normal. CXR had a sensitivity of 58.3%, specificity of 73.9%, PPV of 53.8 %, NPV of 77.2 %, diagnostic OR of 3.7 (95% CI 0.7 - 22) and an accuracy of 68.5% (95% CI 50.7% -83.1%). DiscussionCXR has limited diagnostic accuracy in SAP. The majority of patients started on antibiotics had no evidence of pneumonia on pulmonary CT with potential implications for antibiotic stewardship. ConclusionsPulmonary CT could be applied as a reference standard for evaluation of clinical and biomarker diagnostic SAP algorithms in multi-center studies.

An accurate neural network algorithm to diagnose Covid-19 from CT images

Background: A new coronavirus appeared in late December 2019 in Wuhan, China. He was named Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). This virus is responsible for Covid-19, the name given to the disease associated with it. It spreads worldwide, infecting more than a million people and killing more than 70 miles. The rapid and accurate diagnosis of suspected Covid-19 cases plays a crucial role in medical treatment and timely quarantine. Materials and Methods: In order to counter the Covid-19 pandemic, we have developed a method for the automatic detection of Covid -19, from 2D computed tomography (CT) chest images. It is a supervised software system based on the ANN (Artificial Neural Network) algorithm. Pulmonary CT images were collected from multiple international datasets, with a total of 395 images: 70% were used for training and 30% were used for testing. For each patient, the lungs were segmented using simple thresholding. Then, the segmented lungs were fed into a neural network to predict the probability of SARS-CoV-2 infectious. Results: The internal validation achieved a total accuracy of 97.5% with a specificity of 96.6 % and a 100 % sensitivity. Conclusion: These results demonstrate the proof-ofprinciple for using artificial intelligence to extract radiological features for timely and accurate Covid-19 diagnosis.

Relationship between CT Severity Score and Capillary Blood Oxygen Saturation in Patients with COVID-19 Infection.

Background: COVID-19 pneumonia is responsible for the latest pandemic. Usage of pulmonary computed tomography (CT) scan is known to be an important method in the diagnosis of COVID-19. Here, we aimed to evaluate the relationship between CT severity score and capillary blood oxygen saturation in patients with COVID-19 infection.Methods and material: This is a cross-sectional study performed in 2020 on patients with COVID-19 infection. All patients underwent pulmonary CT scan and CT severity score was calculated. The initial capillary oxygen saturation by the time of admission was also collected. Data were collected and analyzed.Results: A total number of 270 patients diagnosed with COVID-19 infection entered the study. The initial mean capillary oxygen saturation was 89.65 ± 8.09%. The mean score in patients was 15.16 ± 8.08. We also indicated that 27 patients had hypoxia by the time of admission and these patients had significantly higher CT severity scores (p = 0.001). Diabetes mellitus (p = 0.001), hypertension (p = 0.001), and chronic obstructive pulmonary disease (COPD) (p = 0.03) and totally having an underlying disease (p < 0.001) were significantly associated with decreased capillary oxygen saturation. Patients with hypertension (p = 0.001) and patients with the previous medical disease (p = 0.01) had significantly higher CT severity scores than others. There was a significant reverse relationship between CT severity score and capillary oxygen saturation (r = −0.44, p < 0.001).Conclusions: We showed that there was a significant reverse relationship between CT severity score and capillary oxygen saturation which has great clinical importance. Furthermore, we indicated that previous medical history could also play an important role in CT severity score.How to cite this article: Aalinezhad M, Alikhani F, Akbari P, Haji Rezaei M, Soleimani S, Hakamifard A. Relationship between CT Severity Score and Capillary Blood Oxygen Saturation in Patients with COVID-19 Infection. Indian J Crit Care Med 2021;25(3):279–283.

May\u2013Thurner syndrome, a diagnosis to consider in young males with no risk factors: a case report and review of the literature

BackgroundMay–Thurner syndrome is an anatomical condition characterized by compression of the left common iliac vein by the right common iliac artery, causing venous outflow obstruction. It is an uncommon cause of deep vein thrombosis and is more prevalent among women. This paper highlights the importance of considering May–Thurner syndrome in young males without risk factors presenting with left lower limb pain, as endovascular treatment may be required.Case presentationA 23 year-old Caucasian male presented with a 1-week history of left lower limb pain, edema, and pallor. He was found to have an unprovoked deep vein thrombosis on Doppler ultrasound involving the left fibular, soleus, gastrocnemius, popliteal, femoral, common femoral, and external iliac veins. A heparin infusion was commenced as the initial treatment for deep vein thrombosis. Further investigation with computer tomography pulmonary angiogram and computer tomography venography of the abdomen and pelvis showed bilateral pulmonary emboli and left common iliac vein compression with left common, internal, and external iliac vein thrombosis. He was diagnosed with May–Thurner syndrome despite having no risk factors. A retrievable Cook Celect Platinum inferior vena cava filter was placed, and thrombus of the left common femoral, external, and common iliac veins was treated successfully with AngioJet thrombectomy, thrombolysis using 200,000 units of urokinase, angioplasty and stenting using two Cook Zilver Vena venous self-expanding stents. Therapeutic enoxaparin was commenced on discharge. His filter was removed after 10 weeks. Hematological follow-up 4 months later showed an overall negative thrombophilia screen, and anticoagulation was switched to apixaban. He has had no recurrent thrombosis.ConclusionsClinicians should have a low threshold to investigate for May-Thurner syndrome in patients with left lower limb venous thrombotic events regardless of risk factors, as endovascular treatment may be required to minimize the long-term sequelae of deep vein thrombosis. Duplex ultrasound can be used initially for diagnosis, and computer tomography venography used subsequently if the common iliac vein is not visualized on ultrasound. Endovascular treatment is preferred over anticoagulation alone, especially in otherwise fit patients presenting early, the aim being to reduce the chances of chronic venous hypertension in the lower limb.

Is pleural effusion in COVID-19 interstitial pneumonia related to in-hospital mortality?

The recent severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) pandemic has highlighted the importance of pulmonary computed tomography (CT) for diagnosis and prognostic stratification of this new viral pneumonia. 1370 lung CT scans (performed at the time of admission) of consecutive patients hospitalized for SARS-CoV-2 in Northern Italy during the first epidemic wave were analyzed by a radiological CoreLab. The presence of pleural effusion on pulmonary CT scan was present in 188 patients (13.3% of the population) and identified a population with more comorbidities. Patients with pleural effusion had more cardio-respiratory complications with higher mortality. Pleural effusion was an independent predictor of death on multivariate analysis with an HR of 1.4 (95% confidence interval 1-1.9). Pulmonary CT pleural effusion was an independent predictor of mortality.

Clinical study of pulmonary CT lesions and associated bronchiectasis in 115 convalescent patients with novel coronavirus pneumonia (COVID-19) in China.

A total of 115 convalescent inpatients with COVID-19 were enrolled. According to the results of scans of lung lesions via computed tomography (CT), the patients were divided into mild, moderate, and severe groups. The clinical data of the patients were collected, including age, gender, finger pulse oxygen pressure, ventricular rate, body temperature, etc. The correlation between the clinical indicators and the lesions of high-resolution CT (HRCT) and bronchiectasis was analyzed. Among the 115 patients, 82 had no bronchiectasis and 33 had bronchiectasis. The bronchodilation-prone layers mainly included the left and right lower lobe of the lung. The probability of branching in the inflamed area was greater than that in the noninflamed area in patients with COVID-19. There were significant differences in gender, CT lesion range, and number of incidents of bronchiectasis between noninflamed and inflamed areas (P < 0.05). Moreover, there were significant differences in age, total proportion of CT lesions, volume of CT lesions, and total number of patients with bronchiectasis among the three groups (P < 0.05). CT lesion range was positively correlated with the total number of patients with bronchiectasis and patient age (respectively, r = 0.186, P < 0.05; r = 0.029, P < 0.05). The lesion range in HRCT images of lungs in patients with COVID-19 is correlated with bronchodilation. The larger the lesion, the higher the probability of bronchiectasis and the more incidents of bronchiectasis.

Pulmonary vascular enlargement and lesion extent on computed tomography are correlated with COVID-19 disease severity.

PurposeTo assess the relationships among pulmonary vascular enlargement, computed tomography (CT) findings quantified with software, and coronavirus disease (COVID-19) severity.Materials and methodsUltra-high-resolution (UHR) CT images of 87 patients (50 males, 37 females; median age, 63 years) with COVID-19 confirmed using real-time polymerase chain reaction were analyzed. The maximum subsegmental vascular diameter was measured on CT. Total CT lung volume (CTLV total) and lesion extent (ratio of lesion volume to CTLV total) of ground-glass opacities, reticulation, and consolidation were measured using software. Maximum pulmonary vascular diameter and lesion extent were analyzed using Spearman’s correlation analysis. Logistic regression analysis was performed on CT results to predict disease severity. We also assessed changes in these measures on follow-up scans in 16 patients.ResultsAll 23 patients with severe and critical illness had vascular enlargement (> 4 mm). Pulmonary vascular enlargement (odds ratio 3.05, p = 0.018) and CT lesion extent (odds ratio 1.07, p = 0.002) were independent predictors of disease severity after adjustment for age and comorbidities. On follow-up CT, vascular diameter and CT lesion volume decreased (p = 0.001, p = 0.002; respectively), but CTLV total did not change significantly.ConclusionSubsegmental vascular enlargement is a notable finding to predict acute COVID-19 disease severity.Supplementary InformationThe online version contains supplementary material available at 10.1007/s11604-020-01085-2.

Granulomatous-Lymphocytic Interstitial Lung Disease in Common Variable Immunodeficiency-Features of CT and 18F-FDG Positron Emission Tomography/CT in Clinically Progressive Disease.

Common variable immunodeficiency (CVID) is characterized not only by recurrent bacterial infections, but also autoimmune and inflammatory complications including interstitial lung disease (ILD), referred to as granulomatous-lymphocytic interstitial lung disease (GLILD). Some patients with GLILD have waxing and waning radiologic findings, but preserved pulmonary function, while others progress to end-stage respiratory failure. We reviewed 32 patients with radiological features of GLILD from our Norwegian cohort of CVID patients, including four patients with possible monogenic defects. Nineteen had deteriorating lung function over time, and 13 had stable lung function, as determined by pulmonary function testing of forced vital capacity (FVC), and diffusion capacity of carbon monoxide (DLCO). The overall co-existence of other non-infectious complications was high in our cohort, but the prevalence of these was similar in the two groups. Laboratory findings such as immunoglobulin levels and T- and B-cell subpopulations were also similar in the progressive and stable GLILD patients. Thoracic computer tomography (CT) scans were systematically evaluated and scored for radiologic features of GLILD in all pulmonary segments. Pathologic features were seen in all pulmonary segments, with traction bronchiectasis as the most prominent finding. Patients with progressive disease had significantly higher overall score of pathologic features compared to patients with stable disease, most notably traction bronchiectasis and interlobular septal thickening. 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/CT (PET/CT) was performed in 17 (11 with progressive and six with stable clinical disease) of the 32 patients and analyzed by quantitative evaluation. Patients with progressive disease had significantly higher mean standardized uptake value (SUVmean), metabolic lung volume (MLV) and total lung glycolysis (TLG) as compared to patients with stable disease. Nine patients had received treatment with rituximab for GLILD. There was significant improvement in pathologic features on CT-scans after treatment while there was a variable effect on FVC and DLCO.ConclusionPatients with progressive GLILD as defined by deteriorating pulmonary function had significantly greater pathology on pulmonary CT and FDG-PET CT scans as compared to patients with stable disease, with traction bronchiectasis and interlobular septal thickening as prominent features.

Spatiotemporal Free-Form Registration Method Assisted by a Minimum Spanning Tree During Discontinuous Transformations.

The sliding motion along the boundaries of discontinuous regions has been actively studied in B-spline free-form deformation framework. This study focusses on the sliding motion for a velocity field-based 3D+t registration. The discontinuity of the tangent direction guides the deformation of the object region, and a separate control of two regions provides a better registration accuracy. The sliding motion under the velocity field-based transformation is conducted under the [Formula: see text]-Rényi entropy estimator using a minimum spanning tree (MST) topology. Moreover, a new topology changing method of the MST is proposed. The topology change is performed as follows: inserting random noise, constructing the MST, and removing random noise while preserving a local connection consistency of the MST. This random noise process (RNP) prevents the [Formula: see text]-Rényi entropy-based registration from degrading in sliding motion, because the RNP creates a small disturbance around special locations. Experiments were performed using two publicly available datasets: the DIR-Lab dataset, which consists of 4D pulmonary computed tomography (CT) images, and a benchmarking framework dataset for cardiac 3D ultrasound. For the 4D pulmonary CT images, RNP produced a significantly improved result for the original MST with sliding motion (p<0.05). For the cardiac 3D ultrasound dataset, only a discontinuity-based registration indicated activity of the RNP. In contrast, the single MST without sliding motion did not show any improvement. These experiments proved the effectiveness of the RNP for sliding motion.

Effect of Automatic Extraction Accuracy by Different Image Reconstruction Methods Using a Three-dimensional Image Analysis System for Pulmonary Segmentectomy Preoperative CT Angiography

This study aimed to determine the optimal image reconstruction method for preoperative computed tomography (CT) angiography for pulmonary segmentectomy. This study enrolled 20 patients who underwent contrast-enhanced CT examination for pulmonary segmentectomy. The optimal image reconstruction algorithm among four different reconstruction algorithms (filtered back projection, hybrid iterative reconstruction, model- based iterative reconstruction, and deep learning reconstruction [DLR]) was investigated by assessing the CT numbers, vessel extraction ratios, and misclassification ratios. The vessel extraction ratios for main and subsegment branches reconstructed using DLR were significantly higher than those using other reconstruction algorithms (96.7% and 90.8% for pulmonary artery and vein, respectively). The misclassification ratios at the right upper lobe pulmonary vessels (V1 and V2) were especially high because they were close to the superior vena cava, and their CT numbers were similar in all four reconstructions. In conclusion, the DLR allows a high extraction rate of pulmonary blood vessels and a low misclassification rate of automatic extraction.

Single-phase Pulmonary Arteriovenous Separation CT Protocol with Estimated Time of Arrival Method Using 3rd Generation Dual Source CT: Its Success Rate of Pulmonary Arteriovenous Separation in Our Experience of 223 Cases

We retrospectively investigated the success rate of pulmonary arteriovenous separation in a single-phase computed tomography (CT) protocol using the estimated time of arrival (ETA) method. A total of 223 patients who underwent a single-phase CT protocol using the ETA method for pulmonary arteriovenous separation were included in the analysis. Dual source CT (SOMATOM Force, SIEMENS) was used for imaging. The tube voltage was 80 kVp, and the scan mode was turbo flash spiral mode. CT values of main pulmonary artery (MPA), peripheral pulmonary artery (pPA), peripheral pulmonary vein (pPV), left atrium (LA), ascending aorta (AAo) and descending aorta (DAo) were measured. When the difference in CT values on the central side was 100 Hounsfield unit (HU) or more, it was judged that the separation was successful. The mean CT values were 671.9±154 HU for MPA, 424.4±81.2 HU for LA, 551.1±142.6 HU for pPA, 351.6±94.0 HU for pPV, 362.2±75.8 HU for AAo, and 282.7±83.7 HU for DAo. The mean difference in CT values of the pulmonary artery and vein was 247.5±138.9 HU on the central side and 199.5±133.0 HU on the peripheral side. There were 90.1% of cases where the difference in CT values on the central side was 100 HU or more. In addition, a strong positive correlation (r=0.849, p<0.001) was found between the CT value of MPA and the CT value difference on the central side. The success rate of pulmonary arteriovenous separation by the ETA method, which is a method that enables stable pulmonary arteriovenous separation, was 90.1%.

CT Imaging Features of Patients Infected with 2019 Novel Coronavirus

Abstract Novel coronavirus pneumonia is an acute, infectious pneumonia caused by a novel coronavirus infection. Computed tomographic (CT) imaging is one of the main methods to screen and diagnose patients with this disease. Here, the importance and clinical value of chest CT examination in the diagnosis of COVID-19 is expounded, and the pulmonary CT findings of COVID-19 patients in different stages are briefly summarized, thus providing a reference document for the CT diagnosis of COVID-19 patients.

Primary Synovial Sarcoma of the Kidney: A Case Report

Synovial sarcoma originating from the kidney is extremely rare. A 13-year-old girl presented with a mild left flank pain of one-week duration, with no associated history of hematuria or any other systemic symptoms. Computed tomography (CT) demonstrated a 6 × 13 × 9 cm mass in the left kidney. No soft tissue or extrarenal masses were identified. The patient received a combined of treatment with doxorubicin and ifosfamide. A radical nephrectomy was performed in the left kidney with no complications. Postoperative pathology revealed post-chemotherapy residue of monophasic spindle cell synovialosarcoma of the left kidney. She received a combined treatment with doxorubicin and ifosfamide in concomittance with external radiation therapy. The patient was re-examined 4 months after surgery. An abdominal and pulmonary CT found no recurrence or metastasis.

Comparing the clinical, radiological and laboratory characteristics of definite or suspected covid-19 cases

Objective: The present study aims to compare the clinical and laboratory characteristics of patients diagnosed with coronavirus disease (COVID-19) using Real-Time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and Computed Tomography (CT). Materials and Methods: In this study, 240 adult patients were included. The demographic data, symptoms, COVID-19 findings in the initial pulmonary CT during admission and the first laboratory parameters were recorded. The patients were divided into three groups as Group 1 consisting of 100 PCR (+) CT (+) patients, Group 2 consisting of 40 PCR (+) CT (-) patients, Group 3 consisting of 100 PCR (-) CT (+) patients. Results: The mean symptom duration was 5.78 days in Group 1, 2.67 days in Group 2, and 5.26 days in Group 3 (p<0.05). The mean symptom duration was 5.52 days in CT (+) patients and 2.67 days in CT (-) patients (p<0.05). The findings showed that one unit increase in pathological lobe count decreased PCR positivity by 1.3 times (p=0.002). Conclusion: There may not be any findings in CT in the first 48-72 hours after the onset of the symptoms in symptomatic patients, and as the number of pathological pulmonary lobes detected in CT increases, PCR positivity decreases. [ FROM AUTHOR] Copyright of Erciyes Medical Journal / Erciyes Tip Dergisi is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all Abstracts.)