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3.
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.

4.
Phys Med Biol ; 61(11): N291-310, 2016 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-27203621

RESUMO

Conventional proton beam range verification using positron emission tomography (PET) relies on tissue activation alone and therefore requires particle therapy PET whose installation can represent a large financial burden for many centers. Previously, we showed the feasibility of developing patient implantable markers using high proton cross-section materials ((18)O, Cu, and (68)Zn) for in vivo proton range verification using conventional PET scanners. In this technical note, we characterize those materials to test their usability in more clinically relevant conditions. Two phantoms made of low-density balsa wood (~0.1 g cm(-3)) and beef (~1.0 g cm(-3)) were embedded with Cu or (68)Zn foils of several volumes (10-50 mm(3)). The metal foils were positioned at several depths in the dose fall-off region, which had been determined from our previous study. The phantoms were then irradiated with different proton doses (1-5 Gy). After irradiation, the phantoms with the embedded foils were moved to a diagnostic PET scanner and imaged. The acquired data were reconstructed with 20-40 min of scan time using various delay times (30-150 min) to determine the maximum contrast-to-noise ratio. The resultant PET/computed tomography (CT) fusion images of the activated foils were then examined and the foils' PET signal strength/visibility was scored on a 5 point scale by 13 radiologists experienced in nuclear medicine. For both phantoms, the visibility of activated foils increased in proportion to the foil volume, dose, and PET scan time. A linear model was constructed with visibility scores as the response variable and all other factors (marker material, phantom material, dose, and PET scan time) as covariates. Using the linear model, volumes of foils that provided adequate visibility (score 3) were determined for each dose and PET scan time. The foil volumes that were determined will be used as a guideline in developing practical implantable markers.


Assuntos
Marcadores Fiduciais , Tomografia por Emissão de Pósitrons , Terapia com Prótons , Radioterapia Guiada por Imagem/normas , Humanos , Metais , Imagens de Fantasmas , Próteses e Implantes
5.
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
6.
Ann Thorac Surg ; 88(4): e34-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19766774

RESUMO

In an attempt to allow physiologic expansion of the pulmonary autograft, yet limit late root dilation, we used stretch Gore-Tex material (W. L. Gore & Assoc, Flagstaff, AZ) as an external wrap. Follow-up cardiac computed tomography with reconstructed three-dimensional and dynamic images confirmed normal "triple bulge" sinus Valsalva geometry and preserved natural systolic expansion of the neoaortic root.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Materiais Biocompatíveis , Prótese Vascular , Polímeros de Fluorcarboneto , Artéria Pulmonar/cirurgia , Adulto , Angiografia , Insuficiência da Valva Aórtica/complicações , Insuficiência da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/complicações , Estenose da Valva Aórtica/diagnóstico , Ecocardiografia Transesofagiana , Humanos , Masculino , Desenho de Prótese , Técnicas de Sutura , Tomografia Computadorizada por Raios X , Transplante Autólogo
7.
Radiology ; 224(2): 366-72, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12147829

RESUMO

PURPOSE: To report an experience with helical computed tomographic (CT) angiography as the initial procedure to rule out arterial lesions caused by penetrating neck injuries. MATERIALS AND METHODS: During 27 months, 175 patients were referred for helical CT angiography of the neck because of clinical suspicion of arterial injuries. The protocol included a 100-mL bolus of nonionic contrast material injected at 4.5 mL/sec, with 11-second scanning delay, 3-mm collimation, and pitch of 1.3-2.0. CT images were interpreted prospectively by the emergency radiologist, and two radiologists retrospectively interpreted studies with consensus. Outcome was determined with examination of patients and their charts. The sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: Studies in two patients were considered inadequate for diagnosis; these patients were referred for conventional arteriography and had normal findings. In 27 patients (15.6%), arterial lesions were detected. One patient had two arterial injuries. Lesions demonstrated with helical CT angiography were arterial occlusion (n = 14), pseudoaneurysm (n = 8), pseudoaneurysm and arteriovenous fistulae (n = 4), and partial thrombosis (n = 2). The remaining 146 patients had normal arteries. On the basis of these findings, patients were treated with surgery (n = 21), endovascular intervention (n = 7), and observation alone (n = 146). CONCLUSION: Results indicate that helical CT angiography can be used as the initial method for evaluation in patients with possible arterial injuries of the neck.


Assuntos
Angiografia , Lesões do Pescoço/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Ferimentos Penetrantes/diagnóstico por imagem , Adolescente , Adulto , Idoso , Lesões das Artérias Carótidas/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Artéria Vertebral/diagnóstico por imagem , Artéria Vertebral/lesões
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