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2.
Diagn Interv Imaging ; 101(12): 771-781, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32800505

RESUMO

Three-dimensional (3D) visualizations of volumetric data from computed tomography (CT) acquisitions can be important adjuncts to interpretation of two-dimensional (2D) reconstructions. Recently, the 3D technique known as cinematic rendering (CR) was introduced, allowing photorealistic images to be created from standard CT acquisitions. CR methodology is under increasing investigation for use in the display of regions of complex anatomy and as a tool for education and preoperative planning. In this article, we will illustrate the potential utility of CR for evaluating the urinary bladder and associated pathology. The urinary bladder is susceptible to a multitude of neoplastic and inflammatory conditions and their sequelae. The intrinsic properties of CR may prove useful for the display of subtle mucosal/luminal irregularities, the simultaneous display of soft tissue detail with high-resolution maps of associated tumor neovasculature, and the improved display of spatial relationships to aid pre-procedural planning. Further refinement of presets for CR image creation and prospective evaluation of urinary bladder CR in real-world settings will be important for widespread clinical adoption.


Assuntos
Imageamento Tridimensional , Tomografia Computadorizada por Raios X , Bexiga Urinária , Humanos , Estudos Prospectivos , Bexiga Urinária/diagnóstico por imagem
4.
Diagn Interv Imaging ; 101(9): 555-564, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32278586

RESUMO

PURPOSE: The purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC). MATERIALS AND METHODS: Eighty-nine patients with AIP (65 men, 24 women; mean age, 59.7±13.9 [SD] years; range: 21-83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1±12.3 [SD] years; range: 36-86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5mm thickness/increment) were compared with thick-slices images (3 or 5mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing. RESULTS: The pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8-100%), 83.9% (52:67; 95% CI: 74.7-93.0%) and 77.4% (48/62; 95% CI: 67.0-87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6-100%) and 100% specificity (33/33; 95% CI: 93-100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8-100%) and area under the curve of 0.975 (95% CI: 0.936-1.0). CONCLUSIONS: Radiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.


Assuntos
Doenças Autoimunes , Pancreatite Autoimune , Neoplasias Pancreáticas , Pancreatite , Idoso , Doenças Autoimunes/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ductos Pancreáticos , Neoplasias Pancreáticas/diagnóstico por imagem , Pancreatite/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
5.
Diagn Interv Imaging ; 101(1): 35-44, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31358460

RESUMO

PURPOSE: The purpose of this study was to report procedures developed to annotate abdominal computed tomography (CT) images from subjects without pancreatic disease that will be used as the input for deep convolutional neural networks (DNN) for development of deep learning algorithms for automatic recognition of a normal pancreas. MATERIALS AND METHODS: Dual-phase contrast-enhanced volumetric CT acquired from 2005 to 2009 from potential kidney donors were retrospectively assessed. Four trained human annotators manually and sequentially annotated 22 structures in each datasets, then expert radiologists confirmed the annotation. For efficient annotation and data management, a commercial software package that supports three-dimensional segmentation was used. RESULTS: A total of 1150 dual-phase CT datasets from 575 subjects were annotated. There were 229 men and 346 women (mean age: 45±12years; range: 18-79years). The mean intra-observer intra-subject dual-phase CT volume difference of all annotated structures was 4.27mL (7.65%). The deep network prediction for multi-organ segmentation showed high fidelity with 89.4% and 1.29mm in terms of mean Dice similarity coefficients and mean surface distances, respectively. CONCLUSIONS: A reliable data collection/annotation process for abdominal structures was developed. This process can be used to generate large datasets appropriate for deep learning.


Assuntos
Abdome/diagnóstico por imagem , Aprendizado Profundo , Tomografia Computadorizada por Raios X/métodos , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
7.
Diagn Interv Imaging ; 100(9): 467-476, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31047840

RESUMO

Cinematic rendering (CR) is a recently described three-dimensional (3D) rendering technique that generates photorealistic images based on a new lighting model. This review illustrates the potential application of CR in the evaluation of focal liver masses. CR shows promise in improving the visualization of enhancement pattern and internal architecture, local tumor extension, and global disease burden, which may be helpful in focal liver mass characterization and pretreatment planning.


Assuntos
Imageamento Tridimensional/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Fígado/diagnóstico por imagem , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Carcinoma Hepatocelular/diagnóstico por imagem , Colangiocarcinoma/diagnóstico por imagem , Hiperplasia Nodular Focal do Fígado/diagnóstico por imagem , Hemangioma/diagnóstico por imagem , Humanos , Abscesso Hepático/diagnóstico por imagem
8.
Diagn Interv Imaging ; 100(9): 477-483, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30928470

RESUMO

Cinematic rendering (CR) is a new 3D visualization methodology for volumetric diagnostic imaging including computed tomography (CT) datasets composed of isotropic voxels. CR produces photorealistic images with enhanced detail relative to other 3D visualization methods and realistic shadowing. In this review, we provide a number of examples of splenic pathology visualized with CR including conditions affecting the splenic vasculature, neoplasms, and accessory spleens. These examples are compared to 2D CT and traditional 3D CT techniques and the potential advantages of CR are highlighted. CR displays textural changes in the splenic parenchyma to particular advantage, and a portion of this review will be devoted to examples of how textural features can help distinguish intrapancreatic accessory spleens from neuroendocrine tumors.


Assuntos
Imageamento Tridimensional/métodos , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Baço/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Humanos , Invasividade Neoplásica/diagnóstico por imagem , Tumores Neuroendócrinos/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Baço/anormalidades , Neoplasias Esplênicas/diagnóstico por imagem
9.
Clin Radiol ; 72(4): 338.e1-338.e9, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28065641

RESUMO

Hand and wrist infections can present with a spectrum of manifestations ranging from cellulitis to deep-space collections. The various infectious processes can be categorised as superficial or deep infections based on their respective locations relative to the tendons. Superficial hand infections are located superficial to the tendons and are comprised of cellulitis, lymphangitis, paronychia, pulp-space infections, herpetic whitlow, and include volar as well as dorsal subcutaneous abscesses. Deep hand infections are located deep to the tendon sheaths and include synovial space infections, such as infectious tenosynovitis, deep fascial space infections, septic arthritis, necrotising fasciitis, and osteomyelitis. Knowledge of hand and wrist compartmental anatomy is essential for the accurate diagnosis and management of hand infections. Although early and superficial infections of the hand may respond to non-surgical management, most hand infections are surgical emergencies. Multidetector computed tomography (MDCT), with its muliplanar reformation (MPR) and three-dimensional (3D) capabilities, is a powerful tool in the emergency setting for the evaluation of acute hand and wrist pathology. The clinical and imaging features of hand and wrist infections as evident on MDCT will be reviewed with emphasis on contiguous and closed synovial and deep fascial spaces. Knowledge of hand compartmental anatomy enables accurate characterisation of the infectious process and localise the extent of disease in the acute setting.


Assuntos
Infecções Bacterianas/diagnóstico por imagem , Mãos/diagnóstico por imagem , Mãos/microbiologia , Tomografia Computadorizada Multidetectores/métodos , Punho/diagnóstico por imagem , Punho/microbiologia , Humanos , Imageamento Tridimensional/métodos
10.
Diagn Interv Imaging ; 98(3): 191-202, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27614585

RESUMO

Pancreatic serous cystadenoma can be categorized into microcystic, honeycomb, oligocystic, and solid patterns based on imaging appearance. The presence of typical computed tomography (CT) features helps to differentiate serous cystadenomas from other cystic and solid pancreatic masses. Cases with atypical features present a diagnostic challenge as they can mimic malignant neoplasms. This article reviews pathophysiology, prevalence, CT features, mimickers and recommendations for management of pancreatic serous cystadenoma.


Assuntos
Cistadenoma Seroso/diagnóstico por imagem , Cistadenoma Seroso/patologia , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma Mucinoso/diagnóstico por imagem , Carcinoma Papilar/diagnóstico por imagem , Diagnóstico Diferencial , Humanos , Metástase Neoplásica/diagnóstico por imagem , Tumores Neuroendócrinos/diagnóstico por imagem , Pseudocisto Pancreático/diagnóstico por imagem , Doença de von Hippel-Lindau/diagnóstico por imagem
11.
Diagn Interv Imaging ; 97(12): 1259-1273, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27825642

RESUMO

The increasing use of abdominal imaging has led to a growing incidence of traditionally uncommon pancreatic tumors. These rare tumors have specific imaging features whose knowledge may heighten confidence in characterization and may avoid unnecessary surgical procedures when imaging findings suggest a benign condition. Computed tomography (CT) is the modality with which rare pancreatic tumors are incidentally detected in the majority of cases. Magnetic resonance imaging (MRI) is often performed as a second line examination for further characterization. This review provides an update on CT and MRI findings of rare tumors of the pancreas.


Assuntos
Achados Incidentais , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/patologia , Doenças Raras/diagnóstico por imagem , Doenças Raras/patologia , Tomografia Computadorizada por Raios X , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Humanos , Estadiamento de Neoplasias , Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Sensibilidade e Especificidade
13.
Diagn Interv Imaging ; 97(3): 297-306, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26868603

RESUMO

Arteriovenous grafts and fistulas are placed for long-term hemodialysis access, and their associated complications can lead to considerable morbidity. Multi-detector computed tomography (MDCT) images provide accurate delineation of hemodialysis access anatomy and show potential complications. This review makes the reader more familiar with vascular access anatomy and configurations, describes the appearance of access complications encountered on MDCT, and discusses endovascular and surgical treatment options for complications, which should aid in post-treatment evaluation.


Assuntos
Derivação Arteriovenosa Cirúrgica , Angiografia por Tomografia Computadorizada/métodos , Imageamento Tridimensional , Tomografia Computadorizada Multidetectores , Diálise Renal , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Renal/efeitos adversos
14.
Diagn Interv Imaging ; 96(9): 871-83, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25846686

RESUMO

Inflammatory bowel diseases (IBD) are associated with an increased risk of gastrointestinal cancers and more specifically in sites affected by chronic inflammation. However, patients with IBD have also an increased risk for developing a variety of extra-intestinal cancers. In this regard, hepatobiliary cancers, such as cholangiocarcinoma, are more frequently observed in IBD patients because of a high prevalence of primary sclerosing cholangitis, which is considered as a favoring condition. Extra-intestinal lymphomas, mostly non-Hodgkin lymphomas, and skin cancers are also observed with an increased incidence in IBD patients by comparison with that in patients without IBD. This review provides an update on demographics, risk factors and clinical features of extra-intestinal malignancies, including cholangiocarcinoma, hepatocellular carcinoma and lymphoma, that occur in patients with IBD along with a special emphasis on the multidetector row computed tomography and magnetic resonance imaging features of these uncommon conditions.


Assuntos
Doenças Inflamatórias Intestinais/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada Multidetectores/métodos , Neoplasias/diagnóstico , Humanos , Neoplasias/etiologia , Fatores de Risco
15.
Diagn Interv Imaging ; 96(2): 133-49, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24835625

RESUMO

Acute colitis is often diagnosed on multidetector row computed tomography (MDCT) because patients with this condition present with abdominal pain and a variety of nonspecific symptoms. Acute colitis has multiple causes with varying degrees of severity. Analysis of the extent of colonic involvement, presence of specific MDCT imaging features and associated signs should help radiologist narrow the diagnosis. Integrating the results of clinical examination and biological tests is mandatory, and in case of ambiguous or nonspecific MDCT findings, endoscopy and colon biopsy should always be considered for a definite diagnosis. The purpose of this review is to discuss and illustrate MDCT features that are helpful for characterizing acute colitis in adults and to provide an update in current MDCT features.


Assuntos
Colite/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Doença Aguda , Adulto , Colite/classificação , Colite/etiologia , Humanos
16.
Artigo em Inglês | MEDLINE | ID: mdl-34219859

RESUMO

In recent years, iterative algorithms have become popular in diagnostic CT imaging to reduce noise or radiation dose to the patient. The non-linear nature of these algorithms leads to non-linearities in the imaging chain. However, the methods to assess the performance of CT imaging systems were developed assuming the linear process of filtered backprojection (FBP). Those methods may not be suitable any longer when applied to non-linear systems. In order to evaluate the imaging performance, a phantom is typically scanned and the image quality is measured using various indices. For reasons of practicality, cost, and durability, those phantoms often consist of simple water containers with uniform cylinder inserts. However, these phantoms do not represent the rich structure and patterns of real tissue accurately. As a result, the measured image quality or detectability performance for lesions may not reflect the performance on clinical images. The discrepancy between estimated and real performance may be even larger for iterative methods which sometimes produce "plastic-like", patchy images with homogeneous patterns. Consequently, more realistic phantoms should be used to assess the performance of iterative algorithms. We designed and constructed a biological phantom consisting of porcine organs and tissue that models a human abdomen, including liver lesions. We scanned the phantom on a clinical CT scanner and compared basic image quality indices between filtered backprojection and an iterative reconstruction algorithm.

17.
Skeletal Radiol ; 41(8): 887-97, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22366736

RESUMO

Systemic mastocytosis comprises a group of clonal disorders of the mast cell that most commonly involves the skeletal system. Imaging can be helpful in the detection and characterization of the osseous manifestations of this disease. While radiography and bone scans are frequently used for this assessment, low-dose multidetector computed tomography and magnetic resonance imaging can be more sensitive for the detection of marrow involvement and for the demonstration of the various disease patterns. In this article, we review the pathophysiological and clinical features of systemic mastocytosis, discuss the role of imaging for staging and management, and illustrate the various cross-sectional imaging appearances. Awareness and knowledge of the imaging features of this disorder will increase the accuracy of image interpretation and can contribute important information for management decisions.


Assuntos
Neoplasias da Medula Óssea/diagnóstico , Neoplasias Ósseas/diagnóstico , Diagnóstico por Imagem/métodos , Mastocitose Sistêmica/diagnóstico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Inflamm Res ; 58(1): 15-21, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19130178

RESUMO

OBJECTIVES AND DESIGN: The objective of this study was to explore whether increased levels of inflammatory cytokines are associated with the risk of clinically silent coronary artery disease. SUBJECTS: Three-hundred-fifty-six black adults aged 25-54 residing in inner city of Baltimore, Maryland, United States were included in this study. METHODS: Sociodemographics were assessed as were lipid profiles, IL-6, tumor necrosis factor-alpha (TNF-alpha), soluble intercellular adhesion molecule-1 (sICAM-1), and high-sensitivity C-reactive protein (hs-CRP) levels. Computed tomography (CT) coronary angiography was performed. RESULTS: Coronary calcification was identified in 22.5 % participants and 14 % had significant (>or=50 %) coronary stenosis. Multiple logistic regression analyses suggested that IL-6 levels were independently associated with the presence of coronary calcification and significant coronary stenosis, while TNF-alpha, sICAM-1 and hs-CRP levels were not. CONCLUSIONS: This study underscores a critical role for IL-6 in atherosclerosis and suggests that IL-6 may be a marker for significant coronary stenosis in cardiovascularly asymptomatic individuals.


Assuntos
Negro ou Afro-Americano , Doença da Artéria Coronariana , Estenose Coronária , Interleucina-6/sangue , Adulto , Biomarcadores/metabolismo , Pressão Sanguínea/fisiologia , Calcinose/sangue , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/patologia , Estenose Coronária/sangue , Estenose Coronária/etnologia , Estenose Coronária/imunologia , Feminino , Humanos , Lipídeos/sangue , Pessoa de Meia-Idade , Estados Unidos/epidemiologia
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