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1.
Medicine (Baltimore) ; 100(2): e24205, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33466198

RESUMO

OBJECTIVES: Controversies emerge over routine performances of whole-body computed tomography (WBCT) in patients with blunt polytrauma. The existing randomized and non-randomized evidence is inconclusive, and during observations of non-trauma, incidental findings, detected by WBCT, have left uncertainty regarding their consequences and optimal management. Additionally, previous meta-analyses have failed to address the limitations of primary studies and issues associated with incidental findings. Therefore, we planned a new systematic review to address these points. METHODS: We will search the PubMed, EMBASE, and Cochrane Central databases from inception to December 31, 2020, with no language restriction and perform full-text evaluation of potentially relevant articles. We will include prospective and retrospective studies with a single-gate design that assessed diagnostic accuracy and/or yield of WBCT to detect traumatic injuries, and studies that assessed incidental findings detected by WBCT. Additionally, we will include randomized controlled trials and non-randomized comparative studies that assessed the effectiveness of WBCT against conventional care, including selective computed tomography (CT). Studies of patients of all ages with blunt traumatic injuries, assessed at an emergency department, will be included. Two reviewers will extract data and rate the study validity via standard quality assessment tools. The primary outcome of interest will be reduction in mortality. Our secondary outcomes will include diagnostic accuracy and yield, detection of incidental findings and clinical outcomes associated with these detections, and improvement in other non-mortality clinical outcomes. We will qualitatively assess study, patient, and intervention characteristics and clinical outcomes. If appropriate, we will perform random-effects model meta-analyses to obtain summary estimates. Finally, we will assess the certainty of evidence by the grading the quality of evidence and strength of recommendations. ETHICS AND DISSEMINATION: Ethics approval is not applicable, as this is a secondary analysis of publicly available data. The review results will be submitted for publication in peer-reviewed journals. PROSPERO REGISTRATION: CRD42020187852.


Assuntos
Protocolos Clínicos , Imagem Corporal Total/normas , Ferimentos não Penetrantes/diagnóstico por imagem , Humanos , Metanálise como Assunto , Sensibilidade e Especificidade , Revisões Sistemáticas como Assunto , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Imagem Corporal Total/métodos
2.
Am Fam Physician ; 103(1): 42-50, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33382559

RESUMO

The use of diagnostic radiography has doubled in the past two decades. Image Gently (children) and Image Wisely (adults) are multidisciplinary initiatives that seek to reduce radiation exposure by eliminating unnecessary procedures and offering best practices. Patients with an estimated glomerular filtration rate less than 30 mL per minute per 1.73 m2 may have increased risk of nephropathy when exposed to iodinated contrast media and increased risk of nephrogenic systemic fibrosis when exposed to gadolinium-based contrast agents. American College of Radiology Appropriateness Criteria can help guide specific diagnostic imaging choices. Noncontrast head computed tomography is the first-line modality when a stroke is suspected. Magnetic resonance imaging stroke protocols and computed tomography perfusion scans can augment evaluation and potentially expand pharmacologic and endovascular therapy timeframes. Imaging should be avoided in patients with uncomplicated headache syndromes unless the history or physical examination reveals red flag features. Cardiac computed tomography angiography, stress echocardiography, and myocardial perfusion scintigraphy (nuclear stress test) are appropriate for patients with chest pain and low to intermediate cardiovascular risk and have comparable sensitivity and specificity. Computed tomography pulmonary angiography is the preferred test for high-risk patients or those with a positive d-dimer test result, and ventilation-perfusion scintigraphy is reserved for patients with an estimated glomerular filtration rate less than 30 mL per minute per 1.73 m2 or a known contrast allergy. Computed tomography with intravenous contrast is preferred for evaluating adults with suspected appendicitis; however, ultrasonography should precede computed tomography in children, and definitive treatment should be initiated if positive. Ultrasonography is the first-line modality for assessing right upper quadrant pain suggestive of biliary disease. Mass size and patient age dictate surveillance recommendations for adnexal masses. Imaging should not be performed for acute (less than six weeks) low back pain unless red flag features are found on patient history. Ultrasonography should be used for the evaluation of suspicious thyroid nodules identified incidentally on computed tomography.


Assuntos
Imagem por Ressonância Magnética/normas , Neoplasias Induzidas por Radiação/prevenção & controle , Segurança do Paciente/normas , Radiografia/normas , Cintilografia/normas , Humanos , Guias de Prática Clínica como Assunto , Saúde Radiológica , Tomografia Computadorizada por Raios X/normas , Procedimentos Desnecessários/efeitos adversos
3.
Medicine (Baltimore) ; 99(50): e23642, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327343

RESUMO

Malnutrition and cachexia affects the majority of cancer patients and significantly worsens their quality of life and prognosis. However, the diagnostic criteria of malnutrition and cachexia remain a topic under constant debate. To overcome this hurdle, diagnostic tools to objectively detect and quantify the loss of muscle and fat mass are needed. Computed tomography (CT)-based measurement is currently considered the golden standard. Bioelectrical impedance analysis (BIA) is an economical, non-invasive tool but it is seen controversial in patients with cancer and malnutrition because of possible estimation errors.BIA and CT-based analysis of body mass compartments were performed 172 times in 118 cancer patients, within the nutrition program of our institution. Prevalence of malnutrition was determined according to the global leadership initiative on malnutrition criteria. Data obtained for muscle and fat mass from both BIA and CT were correlated using Pearson's ρ. All analyses were performed with an explorative significance level of 5%.45.7% of the cohort were classified as "malnourished." No significant differences were observed between the 2 groups regarding demographic data. Median body mass index, Karnofsky performance status, and nutritional risk score were lower in the malnourished group. Values for muscle and fat mass by BIA and CT were significantly lower in malnourished patients. Correlation of the measured parameters were highly significant between CT-based and BIA measurement. In the overall cohort, correlation of measured muscle mass values by CT and BIA was significant with Pearson's ρ = 0.794 (P < .01). Looking at patients without malnutrition only, Pearson's ρ was 0.754 (P < .01). The correlation of measured fat mass values was equally significant, with Pearson's ρ of 0.748 (P < .01) in the overall cohort and 0.771 (P < .01) in patients with malnutrition.To our knowledge, this is the first study comparing BIA to CT-based body mass analysis in a large cohort of cancer patients with malnutrition. The results suggest that BIA is a valid diagnostic tool for the assessment of muscle and fat mass, even in patients with malnutrition, and could be implemented for the early detection and short-term follow-up of malnutrition and cachexia.


Assuntos
Índice de Massa Corporal , Caquexia/diagnóstico , Impedância Elétrica , Desnutrição/diagnóstico , Neoplasias/complicações , Tomografia Computadorizada por Raios X/normas , Adulto , Fatores Etários , Idoso , Composição Corporal/fisiologia , Caquexia/etiologia , Caquexia/patologia , Estudos Transversais , Feminino , Humanos , Masculino , Desnutrição/etiologia , Desnutrição/patologia , Pessoa de Meia-Idade , Estado Nutricional , Índice de Gravidade de Doença , Fatores Sexuais
4.
Medicine (Baltimore) ; 99(50): e23692, 2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33327359

RESUMO

The purpose of this study was to compare the effectiveness of a metal artifact reduction algorithm (MAR), model-based iterative reconstruction (MBIR), and virtual monochromatic imaging (VMI) for reducing metal artifacts in CT imaging.A phantom study was performed for quantitatively evaluating the dark bands and fine streak artifacts generated by unilateral hip prostheses. Images were obtained by conventional scanning at 120 kilovolt peak, and reconstructed using filtered back projection, MAR, and MBIR. Furthermore, virtual monochromatic images (VMIs) at 70 kilo-electron volts (keV) and 140 keV with/without use of MAR were obtained by dual-energy CT. The extents and mean CT values of the dark bands and the differences in the standard deviations and location parameters of the fine streak artifacts evaluated by the Gumbel method in the images obtained by each of the methods were statistically compared by analyses of variance.Significant reduction of the extent of the dark bands was observed in the images reconstructed using MAR than in those not reconstructed using MAR (all, P < .01). Images obtained by VMI at 70 keV and 140 keV with use of MAR showed significantly increased mean CT values of the dark bands as compared to those obtained by reconstructions without use of MAR (all, <.01). Significant reduction of the difference in the standard deviations used to evaluate fine streak artifacts was observed in each of the image sets obtained with VMI at 140 keV with/without MAR and conventional CT with MBIR as compared to the images obtained using other methods (all, P < .05), except between VMI at 140 keV without MAR and conventional CT with MAR. The location parameter to evaluate fine streak artifacts was significantly reduced in CT images obtained using MBIR and in images obtained by VMI at 140 keV with/without MAR as compared to those obtained using other reconstruction methods (all, P < .01).In our present study, MAR appeared to be the most effective reconstruction method for reducing dark bands in CT images, and MBIR and VMI at 140 keV appeared to the most effective for reducing streak artifacts.


Assuntos
Metais , Próteses e Implantes , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos , Humanos , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/normas
5.
Medicine (Baltimore) ; 99(42): e22433, 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33080676

RESUMO

The chest computed tomography (CT) characteristics of coronavirus disease 2019 (COVID-19) are important for diagnostic and prognostic purposes. The aim of this study was to investigate chest CT findings in COVID-19 patients in order to determine the optimal cut-off value of a CT severity score that can be considered a potential prognostic indicator of a severe/critical outcome.The CT findings were evaluated by means of a severity score that included the extent (0-4 grading scale) and nature (0-4 grading scale) of CT abnormalities. The images were evaluated at 3 levels bilaterally. A receiver operating characteristics (ROC) curve was used to identify the optimal score (Youden's index) predicting severe/critical COVID-19.The study involved 165 COVID-19 patients (131 men [79.4%] and 34 women [20.6%] with a mean age of 61.5 ±â€Š12.5 years), of whom 30 (18.2%) had severe/critical disease and 135 (81.8%) mild/typical disease. The most frequent CT finding was bilateral predominantly subpleural and basilar airspace changes, with more extensive ground-glass opacities than consolidation. CT findings of consolidation, a crazy-paving pattern, linear opacities, air bronchogram, and extrapulmonary lesions correlated with severe/critical COVID-19. The mean CT severity score was 63.95 in the severe/critical group, and 35.62 in the mild/typical group (P < .001). ROC curve analysis showed that a CT severity score of 38 predicted the development of severe/critical symptoms.A CT severity score can help the risk stratification of COVID-19 patients.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/patologia , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/patologia , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Betacoronavirus , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Pandemias , Prognóstico , Curva ROC , Taxa Respiratória , Tomografia Computadorizada por Raios X/métodos
6.
Cancer Imaging ; 20(1): 64, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912319

RESUMO

BACKGROUND: Patients with esophageal cancer (EC) undergo endoscopic ultrasound and CT based cancer staging. Recent technical developments allow improved MRI quality with diminished motion artifact that may allow MRI to compare favorable to CT for noninvasive staging. Hence the purpose of the study was to assess image quality and diagnostic accuracy of 3 T MRI versus CT and EUS for preoperative T-staging of potentially resectable esophageal cancer. METHODS: Between October-2014 and December-2017, esophageal cancer patients with T-staging by EUS were enrolled in this prospective study. Post-operative histopathologic T-staging was the reference standard. All participants underwent MRI [T2- multi-shot turbo spin echo sequence (msTSE), diffusion-weighted imaging (DWI), and 3D gradient-echo based sequence (3D-GRE)] and CT [non-contrast and multiphase contrast-enhanced CT scanning] 5.6 + 3.6 days after endoscopy. Surgery was performed within 3.6 + 3.5 days after imaging. Two blinded endoscopists (reader 1 and 2) and radiologists (reader 3 and 4) independently evaluated EUS and CT/MRI, respectively. Considering the clinical relevance, patients were dichotomized into early (T1 and T2) vs late (T3 and T4) stage cancer before assessment. For statistical purpose, the binary decision was defined as the ability of the imaging technique to diagnose early stage/not early stage esophageal cancer. Diagnostic performance of EUS, MRI and CT was compared using McNemar's test with Bonferroni correction; kappa values were assessed for reader performance. RESULTS: 74 study participants (60 ± 8 yrs.; 56 men) with esophageal cancer were evaluated, of whom 85%(63/74) had squamous cell carcinoma, 61%(45/74) were at early stage and 39%(29/74) were at late stage cancer, as determined by histopathology. Intra- and Inter-reader agreement for pre-operative vs post-operative T-staging was excellent for all imaging modalities. Compared to CT, MRI showed significantly higher accuracy for both the readers (reader3: 96% vs 82%, p = 0.0038, reader4: 95% vs 80%, p = 0.0076, for MRI vs CT, respectively). Further, MRI outperformed EUS with higher specificity (reader 1 vs 3: 59% vs 93%, p = 0.0015, reader 2 vs 4: 66% vs 93%, p = 0.0081, for EUS vs MRI respectively), and accuracy (reader 1 vs 3: 81% vs 96%, p = 0.0022, reader 2 vs 4: 85% vs 95%, p = 0.057, for EUS vs MRI, respectively). CONCLUSION: For resectable esophageal cancer, MRI had better diagnostic performance for tumor staging compared to CT and EUS. TRIAL REGISTRATION: ChiCTR, ChiCTR-DOD, Registered 2nd October 2014, http://www.chictr.org.cn/showproj.aspx?proj=9620.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Endossonografia/normas , Neoplasias Esofágicas/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Endossonografia/métodos , Neoplasias Esofágicas/patologia , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Período Pré-Operatório , Tomografia Computadorizada por Raios X/métodos
8.
Biochem Med (Zagreb) ; 30(3): 030402, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32774118

RESUMO

After December 2019 outbreak in China, the novel Coronavirus infection (COVID-19) has very quickly overflowed worldwide. Infection causes a clinical syndrome encompassing a wide range of clinical features, from asymptomatic or oligosymptomatic course to acute respiratory distress and death. In a very recent work we preliminarily observed that several laboratory tests have been shown as characteristically altered in COVID-19. We aimed to use the Corona score, a validated point-based algorithm to predict the likelihood of COVID-19 infection in patients presenting at the Emergency rooms. This approach combines chest images-relative score and several laboratory parameters to classify emergency room patients. Corona score accuracy was satisfactory, increasing the detection of positive patients' rate.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Serviço Hospitalar de Emergência , Pneumonia Viral/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Biomarcadores/metabolismo , Estudos de Coortes , Infecções por Coronavirus/diagnóstico por imagem , Infecções por Coronavirus/metabolismo , Serviço Hospitalar de Emergência/normas , Reações Falso-Negativas , Humanos , Resultados Negativos , Pandemias , Pneumonia Viral/diagnóstico por imagem , Pneumonia Viral/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa/normas , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
9.
Cancer Imaging ; 20(1): 61, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811559

RESUMO

BACKGROUND: To evaluate the inter- and intrareader agreement and reproducibility of the NI-RADS scoring system and lexicon with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI). METHODS: This retrospective study included 97 CECT and CEMRI scans from 58 treated cases of head and neck squamous cell carcinoma (HNSCC) after the exclusion of head and neck cancers (HNCs) other than SCC and noncontrast and poor quality CT and MRI scans, with a total of 111 primary targets and 124 lymph node (LN) targets. Two experienced readers independently scored the likelihood of residual/recurrence for these targets based on the NI-RADS criteria and filled in report templates for NI-RADS lexicon diagnostic features. Inter- and intraobserver reproducibility was assessed with Cohen's kappa, and the percent agreement was calculated. RESULTS: Almost perfect interreader agreement was found for the final NI-RADS category of the primary lesions and LNs, with K = 0.808 and 0.806, respectively. Better agreement was found for CT than for MRI (K = 0.843 and 0.77, respectively, P value 0.001). There was almost perfect agreement for excluding tissue enhancement (K = 0.826, 95% CI = 0.658-0.993, P value 0.001), with a percent agreement of 96.4%, and substantial agreement for discrete nodular and diffuse mucosal enhancement (K = 0.826, 95% CI = 0.658-0.993, P value 0.001), with a percent agreement of 96.4%. There was fair agreement for focal mucosal nonmass and deep ill-defined enhancement. The intrareader agreement was almost perfect for most of the rated features (K ranging from 0.802 to 1), with the exception of enlarging discrete nodule/mass and focal mucosal nonmass-like enhancement, which had substantial intraobserver agreement (K ranging from 0.768 to 0.786). CONCLUSION: The individual features of NI-RADS show variable degrees of confidence; however, the overall NI-RADS category was not significantly affected.


Assuntos
Sistemas de Dados , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Imagem por Ressonância Magnética/normas , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Tomografia Computadorizada por Raios X/normas , Idoso , Feminino , Humanos , Imagem por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
10.
J Radiol Prot ; 40(3): 877-891, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32604085

RESUMO

OBJECTIVES: The detection of Coronavirus Disease 2019 (COVID-19) by reverse transcription polymerase chain reaction (RT-PCR) has varying sensitivity. Computed tomography (CT) of the chest can verify infection in patients with clinical symptoms and a negative test result, accelerating treatment and actions to prevent further contagion. However, CT employs ionising radiation. The purpose of this study was to evaluate protocol settings, associated radiation exposure, image quality and diagnostic performance of a low-dose CT protocol in a university hospital setting. MATERIALS AND METHODS: Chest CT examinations were performed on a single scanner (Somatom Definition Edge, Siemens Healthineers, Germany) in 105 symptomatic patients (60 male, 45 female). Images were evaluated with regard to protocol parameters, image quality, radiation exposure and diagnostic accuracy. Serial RT-PCR served as the standard of reference. Based on this reference standard sensitivity, specificity, positive and negative predictive values of CT with 95% confidence interval were calculated. RESULTS: The mean effective dose was 1.3 ± 0.4 mSv (0.7-2.9 mSv) for the patient cohort (mean age 66.6 ± 16.7 years (19-94 years), mean body mass index (BMI) 26.6 ± 5.3 kg m-2 (16-46 kg/m2)). A sensitivity of 100 [95% CI: 82-100]%, a specificity of 78 [95% CI: 68-86]%, a positive predictive value of 50 [95% CI: 33-67]% and a negative predictive value of 100 [95% CI: 95-100]% were obtained. No COVID-19 diagnoses were missed by CT. Image noise did not strongly correlate with BMI or patient diameter and was rated as average. CONCLUSIONS: We presented a robust imaging procedure with a chest CT protocol for confident diagnosis of COVID-19. Even for an overweight patient cohort, an associated radiation exposure of only 1.3 ± 0.4 mSv was achieved with sufficient diagnostic quality to exclude COVID-19.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Doses de Radiação , Radiografia Torácica/normas , Tomografia Computadorizada por Raios X/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , Feminino , Hospitais Universitários , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sensibilidade e Especificidade
11.
Zhonghua Wai Ke Za Zhi ; 58(8): 614-618, 2020 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-32727193

RESUMO

Objective: To compare the accuracy of abdominal enhanced CT and endoscopic ultrasound in the staging of gastric cancer after neoadjuvant chemotherapy (yc stage). Methods: Clinic data of 86 locally advanced gastric cancer patients admitted in Gastrointestinal Cancer Center, Peking University Cancer Hospital & Institute from April 2015 to November 2017 were analyzed retrospectively. Totally 86 patients completed both abdominal enhanced CT and endoscopic ultrasound after neoadjuvant chemotherapy. There were 60 males and 26 females, aged (57.8±9.7) years (range: 32 to 76 years). The diagnostic accuracy of abdominal enhanced CT and endoscopic ultrasound for yc stage were calculated by the area under the multiclass receiver operation characteristic curve (M-AUC), retrospectively. McNemar test was used to compared the diagnostic sensitivity. Results: The M-AUC of ycT stage evaluated by abdominal enhanced CT (CT-ycT stage) and by endoscopic ultrasound (EUS-ycT stage) was 0.614 and 0.704, respectively. For middle and lower gastric cancer, the M-AUC of CT-ycT stage was 0.599 and 0.613, respectively, while EUS-ycT stage was 0.558 and 0.709, respectively. For tumor in the lesser and non-lesser curvature, the M-AUC of CT-ycT stage was 0.630 and 0.607, respectively, while EUS-ycT stage was 0.616 and 0.749, respectively. For patients in CT-ycT1-CT-ycT4, there was no statistically significant difference in the sensitivity between CT-ycT stage and EUS-ycT stage (2/18, 2/15, 52.8%(19/36), 8/13 vs. 0, 4/15, 55.6%(20/36), 7/13; χ(2)=2.00, P=0.157; χ(2)=2.00, P=0.157; χ(2)=0.08, P=0.782; χ(2)=0.33, P=0.564). The M-AUC of ycN stage evaluated by abdominal enhanced CT (CT-ycN stage) was 0.654, while ycN stage evaluated by endoscopic ultrasound (EUS-ycN stage) was 0.533. For patients in CT-ycN0, there was statistically significant difference in the sensitivity between CT-ycN stage and EUS-ycN stage (12.7%(7/55) vs. 5.5%(3/55); χ(2)=4.00, P=0.046). For patients in CT-ycN1, N2, and N3, there was no statistically significant difference in the sensitivity between CT-ycN stage and EUS-ycN stage (2/19, 1/10, 0 vs. 1/19, 1/10, 0; χ(2)=1.00, P=0.317; the other P cannot be estimated). Conclusions: There was no significant difference between the diagnostic efficacy of abdominal enhanced CT and endoscopic ultrasound for yc stage of gastric cancer. Considering the invasiveness of ultrasound gastroscopy, it should not be recommend for patients after neoadjuvant chemotherapy routinely.


Assuntos
Antineoplásicos/administração & dosagem , Endossonografia , Estadiamento de Neoplasias/métodos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X , Adulto , Idoso , Endossonografia/métodos , Endossonografia/normas , Feminino , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias/normas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Neoplasias Gástricas/tratamento farmacológico , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
13.
J Med Internet Res ; 22(6): e19569, 2020 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-32568730

RESUMO

BACKGROUND: Coronavirus disease (COVID-19) has spread explosively worldwide since the beginning of 2020. According to a multinational consensus statement from the Fleischner Society, computed tomography (CT) is a relevant screening tool due to its higher sensitivity for detecting early pneumonic changes. However, physicians are extremely occupied fighting COVID-19 in this era of worldwide crisis. Thus, it is crucial to accelerate the development of an artificial intelligence (AI) diagnostic tool to support physicians. OBJECTIVE: We aimed to rapidly develop an AI technique to diagnose COVID-19 pneumonia in CT images and differentiate it from non-COVID-19 pneumonia and nonpneumonia diseases. METHODS: A simple 2D deep learning framework, named the fast-track COVID-19 classification network (FCONet), was developed to diagnose COVID-19 pneumonia based on a single chest CT image. FCONet was developed by transfer learning using one of four state-of-the-art pretrained deep learning models (VGG16, ResNet-50, Inception-v3, or Xception) as a backbone. For training and testing of FCONet, we collected 3993 chest CT images of patients with COVID-19 pneumonia, other pneumonia, and nonpneumonia diseases from Wonkwang University Hospital, Chonnam National University Hospital, and the Italian Society of Medical and Interventional Radiology public database. These CT images were split into a training set and a testing set at a ratio of 8:2. For the testing data set, the diagnostic performance of the four pretrained FCONet models to diagnose COVID-19 pneumonia was compared. In addition, we tested the FCONet models on an external testing data set extracted from embedded low-quality chest CT images of COVID-19 pneumonia in recently published papers. RESULTS: Among the four pretrained models of FCONet, ResNet-50 showed excellent diagnostic performance (sensitivity 99.58%, specificity 100.00%, and accuracy 99.87%) and outperformed the other three pretrained models in the testing data set. In the additional external testing data set using low-quality CT images, the detection accuracy of the ResNet-50 model was the highest (96.97%), followed by Xception, Inception-v3, and VGG16 (90.71%, 89.38%, and 87.12%, respectively). CONCLUSIONS: FCONet, a simple 2D deep learning framework based on a single chest CT image, provides excellent diagnostic performance in detecting COVID-19 pneumonia. Based on our testing data set, the FCONet model based on ResNet-50 appears to be the best model, as it outperformed other FCONet models based on VGG16, Xception, and Inception-v3.


Assuntos
Infecções por Coronavirus/diagnóstico por imagem , Aprendizado Profundo , Pneumonia Viral/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Betacoronavirus , Infecções por Coronavirus/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/patologia , Sensibilidade e Especificidade
14.
PLoS One ; 15(6): e0234644, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544172

RESUMO

OBJECTIVES: To compare objective and subjective image quality of bronchial structures between a 512-pixel and a 1024-pixel image matrix for chest CT in phantoms and in patients. MATERIALS AND METHODS: First, a two-size chest phantom was imaged at two radiation doses on a 192-slice CT scanner. Datasets were reconstructed with 512-, 768-, and 1024-pixel image matrices and a sharp reconstruction kernel (Bl64). Image sharpness and normalized noise power spectrum (nNPS) were quantified. Second, chest CT images of 100 patients were reconstructed with 512- and 1024-pixel matrices and two blinded readers independently assessed objective and subjective image quality. In each patient dataset, the highest number of visible bronchi was counted for each lobe of the right lung. A linear mixed effects model was applied in the phantom study and a Welch's t-test in the patient study. RESULTS: Objective image sharpness and image noise increased with increasing matrix size and were highest for the 1024-matrix in phantoms and patients (all, P<0.001). nNPS was comparable among the three matrices. Objective image noise was on average 16% higher for the 1024-matrix compared to the 512-matrix in patients (P<0.0001). Subjective evaluation in patients yielded improved sharpness but increased image noise for the 1024- compared to the 512-matrix (both, P<0.001). There was no significant difference between highest-order visible bronchi (P>0.07) and the overall bronchial image quality between the two matrices (P>0.22). CONCLUSION: Our study demonstrated superior image sharpness and higher image noise for a 1024- compared to a 512-pixel matrix, while there was no significant difference in the depiction and subjective image quality of bronchial structures for chest CT.


Assuntos
Brônquios/diagnóstico por imagem , Radiografia Torácica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas , Doses de Radiação , Intensificação de Imagem Radiográfica , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/normas , Radiografia Torácica/normas , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas
15.
Cancer Imaging ; 20(1): 39, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546207

RESUMO

PURPOSE: Evaluate the feasibility of fluorine-18 (18F) fluorodeoxyglucose (FDG) positron emission tomography (PET) and magnetic resonance (MR) imaging in patients with gastric cancer by optimizing the scan protocol and to compare the image quality to 18F FDG PET and computed tomography (CT). METHODS: The PET/CT and PET/MR imaging were sequentially performed in 30 patients with gastric cancer diagnosed by gastroscope using a single-injection-with-dual-imaging protocol. After intravenous injection of 18F-FDG (mean, 249 MBq), PET/CT imaging including low-dose CT was performed (mean uptake time, 47 ± 6 min), and PET/MR imaging including a T1-weighted Dixon sequence for attenuation correction and two different T2-weighted sequences was subsequently acquired (88 ± 15 min after 18F-FDG injection). Four series of images (CT from PET/CT, T1W, T2W Half-Fourier acquisition single-shot turbo spin-echo [T2W-HASTE] and T2W-BLADE from PET/MR) were visually evaluated using a 3-4 points scale for: (1) image artifacts, (2) lesion conspicuity and (3) image fusion quality. The characteristics of the primary lesions were assessed and compared between the PET/CT and PET/MR acquisitions. RESULTS: The image quality and lesion conspicuity of the T2W-HASTE images were significantly improved compared to that of the T2W-BLADE images. A significantly higher number of artifacts were seen in the T2W-HASTE images compared with the T1W and CT images (p < 0. 05). No differences in the accuracy of image fusion between PET/MR and PET/CT (p > 0. 05); however, significant difference was seen in the lesion conspicuity measurements (p < 0.05) with T2W-HASTE being superior. For information about the primary lesion characteristics, the T2W-HASTE images provided the most successful identifications compared with those of the T1W and PET/CT (13vs7vs5) images. CONCLUSIONS: PET/MR with the T2W-HASTE was better at revealing the details of local stomach lesions compared with PET/CT imaging. Combining the PET/MR with the T2W-HASTE technique is a promising imaging method for diagnosing and staging gastric cancer.


Assuntos
Imagem por Ressonância Magnética/métodos , Imagem Multimodal/métodos , Tomografia por Emissão de Pósitrons/métodos , Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Fluordesoxiglucose F18 , Humanos , Imagem por Ressonância Magnética/normas , Masculino , Pessoa de Meia-Idade , Imagem Multimodal/normas , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X/normas
16.
Phys Med Biol ; 65(19): 195013, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32580170

RESUMO

As automation in radiation oncology becomes more common, it is important to determine which algorithms are equivalent for a given workflow. Often, algorithm comparisons are performed in isolation; however, clinical context can provide valuable insight into the importance of algorithm features and error magnification in subsequent workflow steps. We propose a strategy for deriving workflow-specific algorithm performance requirements. We considered two independent workflows indicating the need for radiotherapy treatment replanning for 15 head and neck cancer patients (15 planning CTs, 105 on-unit CBCTs). Each workflow was based on a different deformable image registration (DIR) algorithm. Differences in DIR output were assessed using three sets of QA metrics: (1) conventional, (2) workflow-specific, (3) a combination of (1) and (2). For a given set of algorithm metrics, lasso logistic regression modeled the probability of discrepant replan indications. Varying the minimum probability needed to predict a workflow discrepancy produced receiver operating characteristic (ROC) curves. ROC curves were compared using sensitivity, specificity, and the area under the curve (AUC). A heuristic then derived simple algorithm performance requirements. Including workflow-specific QA metrics improved AUC from 0.70 to 0.85, compared to the use of conventional metrics alone. Algorithm performance requirements had high sensitivity of 0.80, beneficial for replan assessments, with specificity of 0.57. This was an improvement over a naïve application of conventional QA criteria, which had sensitivity of 0.57 and specificity of 0.68. In addition, the algorithm performance requirements indicated practical refinements of conventional QA tolerances, indicated where auxiliary workflow processes should be standardized, and may be used to prioritize structures for manual review. Our algorithm performance requirements outperformed current comparison recommendations and provided practical means for ensuring workflow equivalence. This strategy may aid in trial credentialing, algorithm development, and streamlining expert adjustment of workflow output.


Assuntos
Algoritmos , Neoplasias de Cabeça e Pescoço/radioterapia , Processamento de Imagem Assistida por Computador/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/normas , Fluxo de Trabalho , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Humanos , Modelos Logísticos , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X/métodos
17.
Phys Med Biol ; 65(19): 195012, 2020 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-32575082

RESUMO

The aim of this multicentric study is an inter-center benchmarking, to assess how different set tools applied to the same radiomics workflow affected the radiomics features (RFs) values. This topic is of key importance to start collaboration between different centers and to bring radiomic studies from benchmark to bedside. A per-lesion analysis was performed on 56 metastases (mts) selected from 14 patients. A single radiologist performed the segmentation of all mts, and RFs were extracted from the same segmentation of each mts, using two different software and file formats. Potential sources of discrepancies were evaluated. The intraclass correlation coefficient was used to describe how strongly the same radiomic measurements calculated in the two different centers resemble each other. Moreover, means of the relative changes of each RF were calculated, compared and gradually reduced. We showed that, after matching all formulas, discrepancies in RFs calculation between two centers ranged from 1% to 277%. Therefore, we evaluated other sources of variability using a stepwise approach, which led us to reduce the inter-center discrepancies to 0% for 22/25 RFs and below 2% for 3 RFs out of 25. In this study we demonstrated that different radiomic applications and masks formats might strongly impact the computation of some RFs. Therefore, when dealing with multi-center studies it is mandatory to adopt all strategies that can help in limiting the differences, thus keeping in mind the feasibility of these strategies in large cohort studies.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias do Colo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Neoplasias Retais/diagnóstico por imagem , Software , Tomografia Computadorizada por Raios X/normas , Algoritmos , Humanos , Tomografia Computadorizada por Raios X/métodos
18.
Br J Radiol ; 93(1113): 20200082, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32584595

RESUMO

OBJECTIVE: To understand the status of pre-procedural safety practices in radiological examinations at radiology residency training institutions in various Asian regions. METHODS: A questionnaire based on the Joint Commission International Accreditation Standards was electronically sent to 3 institutions each in 10 geographical regions across 9 Asian countries. Questions addressing 45 practices were divided into 3 categories. A five-tier scale with numerical scores was used to evaluate safety practices in each institution. Responses obtained from three institutions in the United States were used to validate the execution rate of each surveyed safety practice. RESULTS: The institutional response rate was 70.0% (7 Asian regions, 21 institutions). 44 practices (all those surveyed except for the application of wrist tags for identifying patients with fall risks) were validated using the US participants. Overall, the Asian participants reached a consensus on 89% of the safety practices. Comparatively, most Asian participants did not routinely perform three pre-procedural practices in the examination appropriateness topic. CONCLUSION: Based on the responses from 21 participating Asian institutions, most routinely perform standard practices during radiological examinations except when it comes to examination appropriateness. This study can provide direction for safety policymakers scrutinizing and improving regional standards of care. ADVANCES IN KNOWLEDGE: This is the first multicenter survey study to elucidate pre-procedural safety practices in radiological examinations in seven Asian regions.


Assuntos
Consenso , Pesquisas sobre Serviços de Saúde , Segurança do Paciente/normas , Qualidade da Assistência à Saúde/normas , Radiografia/normas , Ásia , China , Pesquisas sobre Serviços de Saúde/estatística & dados numéricos , Humanos , Internato e Residência , Japão , Imagem por Ressonância Magnética/normas , Malásia , Tomografia por Emissão de Pósitrons , Radiologia/educação , República da Coreia , Gestão da Segurança/normas , Singapura , Taiwan , Tomografia Computadorizada por Raios X/normas
19.
Medicine (Baltimore) ; 99(22): e20311, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481401

RESUMO

For acute lower gastrointestinal bleeding (LGIB), lower gastrointestinal endoscopy is the preferred initial diagnostic test. However, it is difficult to perform urgently. Computed tomography (CT) is a convenient alternative.This study aimed to determine the diagnostic performance of CT compared to lower endoscopy as an initial test for evaluating acute LGIB.The medical records of 382 patients who visited our emergency department with hematochezia between January 2012 and January 2017 were retrospectively analyzed. Of them, 112 underwent CT, 65 underwent colonoscopy, and 205 underwent sigmoidoscopy as an initial test. For each method, sensitivity, specificity, positive predictive value, and negative predictive value were calculated upon active bleeding site detection and LGIB etiology diagnosis.The sensitivity, specificity, positive predictive value, and negative predictive value of CT for active bleeding site detection were 85.7%, 100%, 100%, and 96.9%, respectively, while those for identifying the etiology of LGIB were 87.4%, 40.0%, 83.5, and 47.6%, respectively.CT was not inferior to lower endoscopy for active bleeding site detection. Early localization and the exclusion of active bleeding were possible with CT. Etiology was diagnosed with high sensitivity and PPV by CT. Thus, CT can be an alternative initial diagnostic tool for evaluating acute LGIB.


Assuntos
Colonoscopia/métodos , Hemorragia Gastrointestinal/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Centros Médicos Acadêmicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Colonoscopia/normas , Feminino , Hemorragia Gastrointestinal/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Sigmoidoscopia/métodos , Sigmoidoscopia/normas , Tomografia Computadorizada por Raios X/normas , Adulto Jovem
20.
J Surg Res ; 255: 106-110, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32543374

RESUMO

BACKGROUND: Pediatric brain injuries are common, but current management of patients with mild traumatic intracranial hemorrhage (T-ICH) is suboptimal, often including unnecessary repeat head CT (RHCT) and neurosurgical consultation (NSC). Brain Injury Guidelines (BIG) have been developed to standardize the management of TBI, and recent work suggests they may be applied to children. The aim of this study was to apply BIG to a low-risk pediatric TBI population to further determine whether the framework can be safely applied to children in a way that reduces overutilization of RHCTs and NSC. METHODS: A retrospective chart review of a Level I Adult and Pediatric Trauma Center's pediatric registry over 4 y was performed. BIG was applied to these patients to evaluate the utility of RHCT and need for neurosurgical intervention (NSG-I) in those meeting BIG-1 criteria. Those with minor skull fracture (mSFx) who otherwise met BIG-1 criteria were also included. RESULTS: Twenty-eight patients with low-risk T-ICH met criteria for review. RHCT was performed in seven patients, with only two being prompted by clinical neurologic change/deterioration. NSC occurred in 21 of the cases. Ultimately, no patient identified by BIG-1 ± mSFx required NSG-I. CONCLUSIONS: Application of BIG criteria to children with mild T-ICH appears capable of reducing RHCT and NSC safely. Additionally, those with mSFx that otherwise fulfill BIG-1 criteria can be managed similarly by acute care surgeons. Further prospective studies should evaluate the application of BIG-1 in larger patient populations to support the generalizability of these findings.


Assuntos
Tomada de Decisão Clínica/métodos , Hemorragia Intracraniana Traumática/cirurgia , Procedimentos Neurocirúrgicos/normas , Provedores de Redes de Segurança/normas , Centros de Traumatologia/normas , Adolescente , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Fidelidade a Diretrizes/normas , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Escala de Gravidade do Ferimento , Hemorragia Intracraniana Traumática/diagnóstico , Masculino , Procedimentos Neurocirúrgicos/estatística & dados numéricos , Seleção de Pacientes , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Encaminhamento e Consulta/normas , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Provedores de Redes de Segurança/estatística & dados numéricos , Tomografia Computadorizada por Raios X/normas , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Centros de Traumatologia/estatística & dados numéricos , Resultado do Tratamento
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