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1.
J Anim Ecol ; 93(4): 393-405, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38100230

RESUMO

Comprehending symbiont abundance among host species is a major ecological endeavour, and the metabolic theory of ecology has been proposed to understand what constrains symbiont populations. We parameterized metabolic theory equations to investigate how bird species' body size and the body size of their feather mites relate to mite abundance according to four potential energy (uropygial gland size) and space constraints (wing area, total length of barbs and number of feather barbs). Predictions were compared with the empirical scaling of feather mite abundance across 106 passerine bird species (26,604 individual birds sampled), using phylogenetic modelling and quantile regression. Feather mite abundance was strongly constrained by host space (number of feather barbs) but not by energy. Moreover, feather mite species' body size was unrelated to the body size of their host species. We discuss the implications of our results for our understanding of the bird-feather mite system and for symbiont abundance in general.


Assuntos
Doenças das Aves , Infestações por Ácaros , Ácaros , Passeriformes , Animais , Filogenia , Tamanho Corporal , Infestações por Ácaros/veterinária
2.
J Card Surg ; 37(12): 4172-4177, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36198144

RESUMO

The evaluation of patients following aortic valve replacement has evolved, with multiple imaging modalities available that complement each other and permit better and prompt delineation of specific structural or functional valve complications. Multidetector computed tomography (MDCT) is one of the diagnostic modalities with significant technologic advancements that have made possible to evaluate high detail of the moving heart. The ability to deliver three-dimensional and multiplanar dynamic imaging with fine detail has demonstrated the technique is well suited to investigate valve complications. In this review article, we focus on some of the most contributing roles of MDCT in the diagnosis of complications associated with valvular pathology.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Trombose , Substituição da Valva Aórtica Transcateter , Humanos , Tomografia Computadorizada Multidetectores/efeitos adversos , Tomografia Computadorizada Multidetectores/métodos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Estenose da Valva Aórtica/cirurgia , Trombose/diagnóstico por imagem , Trombose/etiologia , Trombose/cirurgia
4.
Radiology ; 275(3): 822-31, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25584706

RESUMO

PURPOSE: To examine the association between pre-radiation therapy (RT) fluorine 18 fluorodeoxyglucose (FDG) uptake and post-RT symptomatic radiation pneumonitis (RP). MATERIALS AND METHODS: In accordance with the retrospective study protocol approved by the institutional review board, 228 esophageal cancer patients who underwent FDG PET/CT before chemotherapy and RT were examined. RP symptoms were evaluated by using the Common Terminology Criteria for Adverse Events, version 4.0, from the consensus of five clinicians. By using the cumulative distribution of standardized uptake values (SUVs) within the lungs, those values greater than 80%-95% of the total lung voxels were determined for each patient. The effect of pre-chemotherapy and RT FDG uptake, dose, and patient or treatment characteristics on RP toxicity was studied by using logistic regression. RESULTS: The study subjects were treated with three-dimensional conformal RT (n = 36), intensity-modulated RT (n = 135), or proton therapy (n = 57). Logistic regression analysis demonstrated elevated FDG uptake at pre-chemotherapy and RT was related to expression of RP symptoms. Study subjects with elevated 95% percentile of the SUV (SUV95) were more likely to develop symptomatic RP (P < .000012); each 0.1 unit increase in SUV95 was associated with a 1.36-fold increase in the odds of symptomatic RP. Receiver operating characteristic (ROC) curve analysis resulted in area under the ROC curve of 0.676 (95% confidence interval: 0.58, 0.77), sensitivity of 60%, and specificity of 71% at the 1.17 SUV95 threshold. CT imaging and dosimetric parameters were found to be poor predictors of RP symptoms. CONCLUSION: The SUV95, a biomarker of pretreatment pulmonary metabolic activity, was shown to be prognostic of symptomatic RP. Elevation in this pretreatment biomarker identifies patients at high risk for posttreatment symptomatic RP.


Assuntos
Neoplasias Esofágicas/radioterapia , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons , Pneumonite por Radiação/diagnóstico , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Estudos Retrospectivos , Medição de Risco
5.
Pediatr Radiol ; 45(7): 1091-4, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25480435

RESUMO

Acute appendicitis is a common pediatric surgical emergency. Successful surgical appendectomy requires removal of the appendix and its contents. A retained appendicolith is a complication that occurs when the appendicolith is expulsed from the appendix as a result of perforation or failure of removal during surgery. An ectopic appendicolith can migrate to a variety of ectopic locations, acting as a nidus for abscess. Clinical presentation may be delayed by days, weeks or even months after surgery. We present and discuss an unusual case of empyema caused by migration of an appendicolith into the chest cavity. Management of these retained appendicoliths requires drainage of the abscess and extraction of the appendicolith.


Assuntos
Apendicite/cirurgia , Empiema/diagnóstico por imagem , Litíase/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico , Doença Aguda , Apendicectomia , Apêndice/cirurgia , Pré-Escolar , Diagnóstico Diferencial , Drenagem , Empiema/cirurgia , Feminino , Humanos , Litíase/cirurgia , Complicações Pós-Operatórias/cirurgia , Radiografia Torácica , Tórax/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ultrassonografia
6.
Indian J Radiol Imaging ; 33(3): 394-399, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37362356

RESUMO

Paragangliomas are neuroendocrine tumors of the sympathetic and parasympathetic nervous system that originate from neural crest cells. Less than 1% of paragangliomas are found in the heart, originating from intrinsic cardiac ganglia cells in the posterior wall the atria, atrioventricular groove, and along the root of the great vessels. A 10-year review of our institution's database identified nine patients who had documented intrapericardial paragangliomas. We describe the multimodality imaging appearance of these tumors. The most common findings include embedment and wrapping around the great vessels and atrioventricular groove within the confines of the pericardium, markedly avid heterogeneous enhancement, distinct engorged neovascularization, and in large lesions, central low attenuation areas compatible with hemorrhage, necrosis, or cystic degeneration.

7.
Radiol Case Rep ; 17(8): 2639-2642, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35663809

RESUMO

This case report describes the findings of septic pulmonary embolism (SPE) in a young adult male with a history of intravenous drug use who initially presented with signs and symptoms of acute sepsis. The patient underwent evaluation by computed tomography (CT) imaging as well as blood cultures and echocardiography, which confirmed the diagnosis of SPE secondary to Staphylococcus aureus positive bacterial endocarditis. In this case report, we discuss the presentation and characteristic CT imaging findings of SPE as well as highlight the value of this imaging modality in the timely diagnosis and management of this urgent condition.

9.
Semin Ultrasound CT MR ; 43(3): 221-229, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35688533

RESUMO

Pulmonary embolism (PE) can present with a wide spectrum of clinical symptoms that can overlap considerably with other cardiovascular diseases. To avoid PE related morbidity and mortality, it is vital to identify this disease accurately and in a timely fashion. Several clinical criteria have been developed to standardize the diagnostic approach for patients with suspected PE. Computed tomographic pulmonary angiogram has significantly improved the detection of pulmonary embolism and is considered the imaging modality of choice to diagnose this disease. However, there are several potential pitfalls associated with this modality which can make diagnosis of PE challenging. In this review, we will discuss various pitfalls routinely encountered in the diagnostic work up of patients with suspected PE, approaches to mitigate these pitfalls and incidental pulmonary embolism.


Assuntos
Embolia Pulmonar , Angiografia , Humanos , Embolia Pulmonar/diagnóstico por imagem , Tomografia Computadorizada por Raios X
10.
AJR Am J Roentgenol ; 197(3): W452-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21862772

RESUMO

OBJECTIVE: The purpose of this article is to present the spectrum of inflammatory bowel disease manifestations in the chest, including the airways, lung parenchyma, pulmonary vasculature, and serosal surfaces. CONCLUSION: The spectrum of inflammatory bowel disease manifestations in the chest is broad, and the manifestations may mimic other diseases. Knowledge of these manifestations in conjunction with pertinent clinical data is essential for establishing the correct diagnosis and treatment.


Assuntos
Doenças Inflamatórias Intestinais/complicações , Doenças Respiratórias/diagnóstico por imagem , Doenças Respiratórias/etiologia , Meios de Contraste , Humanos , Radiografia Torácica , Tomografia Computadorizada por Raios X
11.
Radiol Case Rep ; 16(12): 3666-3671, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34630797

RESUMO

This case reports demonstrates the rare but potentially serious complication of pulmonary vein stenosis and subsequent thrombosis diagnosed two years after radiofrequency ablation of the pulmonary veins for atrial fibrillation. Pulmonary vein stenosis can remain asymptomatic until significant occlusion occurs, after which it can present with a variety of symptoms, mimicking a myriad of cardiovascular and pulmonic pathologies. Early diagnosis and treatment rely on consistent follow up using appropriate diagnostic imaging modalities and is paramount in preventing severe complications.

12.
Radiol Cardiothorac Imaging ; 3(6): e210217, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34934950

RESUMO

Cardiac MRI is clinically feasible in the setting of submassive pulmonary embolism and is able to demonstrate measurable differences of right heart function before and after catheter-directed therapy.

13.
Radiol Case Rep ; 16(6): 1564-1569, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33981378

RESUMO

Pleuroparenchymal fibroelastosis (PPFE) is a rare idiopathic interstitial pneumonia that is often underdiagnosed on computed tomography scans. The disease process involves a combination of fibrosis involving the visceral pleura and fibroelastic changes within the subpleural lung parenchyma. Although definitive diagnosis is based on pathological evaluation, this is often not feasible and pattern recognition on CT as "definite PPFE" or "consistent with PPFE" is important given that sub group of patients will undergo rapid progression with clinical deterioration.

14.
J Biomech ; 122: 110461, 2021 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-33901933

RESUMO

The treatment of aortic disease is complex, requiring cardiothoracic and vascular surgeons to make pre-, post- and intraoperative decisions directly influencing patient survival and well-being. Despite tremendous advancement in vascular surgery and endovascular techniques in the last two decades, along with the abundance of research in the field, many unmet needs and unanswered questions remain. Tight collaboration between engineers and physicians is a keystone in translating new tools, techniques, and devices into practice. Here, we have gathered our perspective, as physicians and engineers, in several pressing issues associated with the diagnosis and treatment of aortic aneurysms and dissection, referring to the current knowledge and practice, signifying unmet needs as well as future directions.


Assuntos
Aneurisma da Aorta Torácica , Aneurisma Aórtico , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Médicos , Dissecção Aórtica/cirurgia , Aneurisma Aórtico/terapia , Aneurisma da Aorta Torácica/cirurgia , Dissecação , Humanos , Resultado do Tratamento
15.
Radiol Clin North Am ; 59(2): 219-229, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33551083

RESUMO

Esophageal cancer is an uncommon malignancy that ranks sixth in terms of mortality worldwide. Squamous cell carcinoma is the predominant histologic subtype worldwide whereas adenocarcinoma represents the majority of cases in North America, Australia, and Europe. Esophageal cancer is staged using the American Joint Committee on Cancer and the International Union for Cancer Control TNM system and has separate classifications for the clinical, pathologic, and postneoadjuvant pathologic stage groups. The determination of clinical TNM is based on complementary imaging modalities, including esophagogastroduodenoscopy/endoscopic ultrasound; endoscopic ultrasound-fine-needle aspiration; computed tomography of the chest, abdomen, and pelvis; and fluorodeoxyglucose PET/computed tomography.


Assuntos
Diagnóstico por Imagem/métodos , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Metástase Linfática/diagnóstico por imagem , Metástase Linfática/patologia , Esôfago/diagnóstico por imagem , Esôfago/patologia , Humanos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Estadiamento de Neoplasias
16.
Semin Ultrasound CT MR ; 42(6): 535-541, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34895609

RESUMO

The management of patients with esophageal carcinoma (EC) requires accurate clinical staging and post-therapeutic evaluation. Currently, esophagogastroduodenoscopy/endoscopic ultrasound (EGD/EUS), endoscopic ultrasound-fine needle aspiration (EUS-FNA), computed tomography (CT), 18F- fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT) and magnetic resonance (MR) imaging are used for the initial clinical staging, evaluation of therapeutic response and follow-up in patients with EC. However, there are limitations and pitfalls that are commonly encountered when imaging these patients that can limit accurate assessment. Knowledge of the limitations and pitfalls associated with the use of these different imaging modalities is essential in avoiding misinterpretation and guaranteeing the appropriate management for patient with EC.


Assuntos
Carcinoma , Neoplasias Esofágicas , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Humanos , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons
17.
Ann Diagn Pathol ; 14(6): 443-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21074694

RESUMO

Diffuse panbronchiolitis (DPB) is an idiopathic inflammatory process involving respiratory bronchioles, largely restricted to Japanese people and associated with HLA Bw54. We report a case of idiopathic bronchiolitis with DPB features in an African American with hepatitis C virus infection, correlated with postmortem anatomic findings. The 53-year-old patient presented with shortness of breath and productive cough. Examination revealed hypercapnic respiratory failure. Lung computed tomography showed diffuse centrilobular nodules and branching linear opacities, whereas lung biopsy demonstrated diffuse peribronchiolar fibrosis and chronic inflammation with bronchiolectasis. He died 37 days postadmission. Autopsy revealed numerous bronchiolocentric nodules with bronchiolectasis and sheets of foamy macrophages in alveolar septa and spaces. This is a rare example of idiopathic bronchiolitis with features of DPB in an hepatitis C virus-infected African-American patient. Hepatitis C virus infection is known to be associated with extrahepatic pulmonary manifestations, and DPB may be one of these. Early diagnosis will allow appropriate treatment and may slow the disease progression.


Assuntos
Negro ou Afro-Americano/etnologia , Bronquiolite/etnologia , Bronquiolite/etiologia , Hepatite C/complicações , Bronquiolite/diagnóstico , Evolução Fatal , Infecções por Haemophilus/diagnóstico , Infecções por Haemophilus/etnologia , Infecções por Haemophilus/etiologia , Humanos , Pulmão/patologia , Macrófagos Alveolares/patologia , Masculino , Pessoa de Meia-Idade
18.
Curr Probl Diagn Radiol ; 48(2): 172-183, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29549978

RESUMO

Positron emission tomography (PET) computed tomography (CT) with 2-[fluorine-18] fluoro-2-deoxy-d-glucose (FDG) has been established as an effective modality for evaluation of cancer. Interpretations of patterns of physiologic 18F-FDG uptake by the heart is particularly difficult given the wide normal variations of 18F-FDG metabolic activity observed. Atypical patterns of focal or diffuse physiologic cardiac 18F-FDG uptake and post-therapeutic effects after radiation therapy, systemic diseases, or cardiomyopathy may also be confused with malignant disease on 18F-FDG PET/CT. In this article, we review the variations of normal cardiac 18F-FDG uptake observed in oncology patients and the appearances of other patterns of pathologic metabolic activity, related or not related to the malignancy being investigated, that may lead to false-negative and false-positive results.


Assuntos
Erros de Diagnóstico , Fluordesoxiglucose F18/farmacocinética , Coração/diagnóstico por imagem , Miocárdio/metabolismo , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos/farmacocinética , Humanos , Neoplasias/diagnóstico por imagem
19.
Clin Imaging ; 51: 23-29, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29414520

RESUMO

The imaging modalities available to evaluate anastomotic leak complicating esophagectomy include CT-Esophageal Protocol (CTEP) and esophagram. The purpose of this study was to compare the performance of these two modalities, alone or in combination, with the final diagnosis of leak established by endoscopy, surgery and/or the clinical course and evaluate management implications.


Assuntos
Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/diagnóstico por imagem , Diagnóstico por Imagem/métodos , Neoplasias Esofágicas/cirurgia , Esofagectomia/efeitos adversos , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos
20.
Br J Radiol ; 91(1082): 20170341, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29125331

RESUMO

OBJECTIVE: The purpose of this study was to evaluate fludeoxyglucose-positron emission ;tomography/CT's (FDG-PET/CT) performance in the follow ;up of patients with surgically treated oesophageal adenocarcinoma. METHODS: The follow-up FDG-PET/CT scans of 162 consecutive patients with surgically treated oesophageal adenocarcinoma were retrospectively reviewed. Histopathological and/or imaging examinations confirmed recurrent disease. The accuracy, sensitivity, specificity and negative and positive predictive values were calculated. RESULTS: Recurrence occurred in 71 (43%) patients, usually within the first year following surgery (60%) and in more than one site (76%). The sensitivity, specificity, positive-predictive value, negative-predictive value and accuracy of FDG-PET/CT for anastomotic recurrence were 77, 76, 16, 98 and 76%; for regional nodal recurrence were 88, 85, 43, 97 and 86%; and for distant metastatic recurrence were: 97, 96, 91, 99 and 96%. In 5 of the 42 patients (12%) with distant metastases, the metastatic sites were outside the area covered by a conventional follow-up chest-abdomen CT and in 4 patients (9%) metastases were barely perceptible on the CT component of the FDG-PET/CT and consequently were unlikely to be detected without the aid of the FDG uptake. CONCLUSION: FDG PET/CT is accurate in detecting oesophageal adenocarcinoma recurrence, especially within the first post-operative year when most recurrences occur, and is useful in identifying patients with a solitary metastasis. Advances in knowledge: FDG-PET/CT should be considered as a valuable tool in the routine follow ;up of surgically treated oesophageal cancer patients within the first 2 years after surgery.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias Esofágicas/diagnóstico por imagem , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Compostos Radiofarmacêuticos , Adenocarcinoma/cirurgia , Idoso , Neoplasias Esofágicas/cirurgia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Valor Preditivo dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X
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