RESUMO
Coronary artery calcification quantification (scoring) has been done with electron beam CT (EBCT), but is now being done with spiral or helical CT. Many radiologists and cardiologists who do not have EBCT but do have access to spiral CT will now be able to do coronary artery calcification scoring, and will now need to know the spiral CT appearance of the coronary artery anatomy. This pictorial review will demonstrate the anatomy needed for coronary artery calcium scoring.
Assuntos
Calcinose/diagnóstico por imagem , Angiografia Coronária/métodos , Doença das Coronárias/diagnóstico por imagem , Vasos Coronários/anatomia & histologia , Tomografia Computadorizada por Raios X , HumanosRESUMO
Joule heating has long been considered the principal component of tissue damage in electrical injury. Recent studies suggest electroporation, a nonthermally mediated mechanism of cell membrane damage, is also a factor. We investigated whether electroporation-mediated muscle necrosis can occur in vivo without significant Joule heating. Pulsed electric fields approximately 150 V/cm were produced in the hind limbs of anesthetized rats. In shocked limbs core muscle temperature rose less than 1.8 degrees C, yet significant damage occurred as determined by technetium-99m pyrophosphate uptake, elevated serum creatine phosphokinase, and prominent hypercontraction band degeneration of myofibers on histopathologic examination. This study is significant because it directly addresses whether nonthermal mechanisms of cell damage can cause tissue necrosis. These results indicate that electroporation effects can mediate skeletal muscle necrosis without visible thermal changes. Thus the phenomenon of "progressive recognition" may be characteristically largely explained by the occurrence of nonthermally mediated tissue damage.
Assuntos
Distinções e Prêmios , Queimaduras por Corrente Elétrica/patologia , Músculo Esquelético/lesões , Músculo Esquelético/patologia , Animais , Queimaduras por Corrente Elétrica/fisiopatologia , Sobrevivência Celular , Creatina Quinase/metabolismo , Modelos Animais de Doenças , Feminino , Músculo Esquelético/irrigação sanguínea , Necrose , Ratos , Ratos Sprague-Dawley , Pirofosfato de Tecnécio Tc 99mRESUMO
We have described a mobile miniature-gamma-camera system for use in electrical trauma units and have presented images and imaging characteristics of a prototype system. The system has as its principal component a miniature gamma camera based on a PSPMT. The camera is 92 mm x 92 mm x 190 mm in size, weighs 5 kg, has a 48 mm x 48 mm field of view, and has an intrinsic resolution of approximately 3 mm FWHM and 6 mm FWTM. It is expected that devices of this type will be useful as imaging tools in electrical trauma units and laboratories where imaging studies regarding uptake mechanisms of radiopharmaceuticals for assessing tissue viability are carried out.
Assuntos
Câmaras gama , Traumatismos por Eletricidade/diagnóstico por imagem , Desenho de Equipamento , Humanos , Miniaturização , CintilografiaRESUMO
The technique of applying an air gap between the patient and the x-ray detector reduces scattered radiation from the patient's neck sufficiently to allow performance of DSA of the extracranial carotid arteries with the antiscatter grid removed. When compared with the conventional grid technique, air gap allows 25 to 88% reduction of mA without increasing the kVp or exposure time and without loss of spatial resolution or diagnostic image quality. These considerable patient radiation-exposure savings can be implemented on DSA systems that use ordinary under-table x-ray tube fluoroscopic equipment without the purchase of additional hardware.
Assuntos
Artérias Carótidas/diagnóstico por imagem , Angiografia Cerebral/métodos , Técnica de Subtração , Humanos , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Espalhamento de RadiaçãoRESUMO
A case of spontaneous regression of lymphoma is presented. Regression of the tumor occurred during an episode of mechanical small bowel obstruction. Elevated circulating endogenous corticosteroids are thought to have acted against the tumor cells.
Assuntos
Linfoma não Hodgkin/diagnóstico por imagem , Neoplasias do Mediastino/diagnóstico por imagem , Recidiva Local de Neoplasia , Regressão Neoplásica Espontânea , Idoso , Feminino , Humanos , RadiografiaRESUMO
Allergic bronchopulmonary aspergillosis (ABPA) has been recognized increasingly in the past few years. In minimal disease, plain chest films may be insensitive. Early detection of pulmonary involvement may help prevent irreversible damage to the lungs and bronchi. Bronchography, while both sensitive and specific, is not without hazard, particularly to the asthmatic patient. We evaluated the usefulness of linear tomography in confirming ABPA prior to initiation of corticosteroid therapy. We find that tomography is a simple, noninvasive instrument for detecting the presence of or proving the absence of the earliest manifestations of ABPA.
Assuntos
Corticosteroides/uso terapêutico , Aspergilose Broncopulmonar Alérgica/diagnóstico por imagem , Tomografia por Raios X , Adolescente , Adulto , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Broncografia , Criança , Feminino , Humanos , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-IdadeRESUMO
Indurative mastopathy is a benign, elastotic lesion of the breast characterized by a stellate appearance, with surrounding compressed and distorted ducts causing a pseudo-infiltrative pattern. In previously reported cases of benign sclerosing lesions of the breast there has been no evidence of local recurrence of metastasis following excisional biopsy. The significance of identifying indurative mastopathy lies in recognizing its benign nature despite clinical, radiographic, and gross histologic features that are indistinguishable from malignancy, thereby saving the patient additional surgery or radiotherapy once an excisional biopsy has been performed.
Assuntos
Doenças Mamárias/diagnóstico por imagem , Adulto , Idoso , Biópsia , Mama/patologia , Doenças Mamárias/patologia , Tecido Elástico/patologia , Reações Falso-Positivas , Feminino , Humanos , Mamografia , Pessoa de Meia-IdadeRESUMO
Allergic bronchopulmonary aspergillosis (ABPA) is a disease of asthmatics that follows a protracted course. When ABPA is treated with high dose corticosteroids, it presents a difficult problem in clinical management. Five stages, based on clinical, roentgenographic, and immunologic criteria, have been identified as follows: (I) acute, (II) remission, (III) exacerbation, (IV) corticosteroid-dependent asthma, and (V) pulmonary fibrosis. We studied 24 ABPA patients actively followed for up to 11 years at our institution. We conclude that while there are no unique roentgenographic findings to define a particular stage, clinicoroentgenographic staging does aid in therapeutic management. Two major roentgenographic contributions are (1) to establish the diagnosis by demonstrating proximal bronchiectasis, and (2) to provide a baseline for an individual patient against which to monitor progressive changes and remissions.
Assuntos
Aspergilose Broncopulmonar Alérgica/diagnóstico por imagem , Doença Aguda , Adolescente , Corticosteroides/uso terapêutico , Adulto , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Aspergilose Broncopulmonar Alérgica/patologia , Criança , Feminino , Seguimentos , Humanos , Masculino , Radiografia , RecidivaRESUMO
Carcinoma of the breast in women less than 40 years old is a significant problem, representing 7.4 per cent of the total number of carcinomas of the breast at our institution. It is apparent that mammography in this age group is of value in confirming the clinical suspicion of a malignant condition of the breast and in evaluating the remainder of the parenchyma of the breast for clinically occult lesions. However, one cannot over emphasize that a negative result from the mammogram should not delay biopsy in the presence of clinically suspicious lesions (1, 4). It is obvious that a larger series of patients is necessary to define the role of mammography in "young women."
Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma/diagnóstico por imagem , Mamografia , Adulto , Fatores Etários , Neoplasias da Mama/fisiopatologia , Carcinoma/fisiopatologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Feminino , Humanos , Estudos RetrospectivosRESUMO
In visualizing the kidneys and renal arteries, the digital subtraction angiography (DSA) image is degraded by peristalsis and overlying bowel gas. In 25 patients we evaluated the efficacy of the prone position to counter these technical difficulties and found that the prone position offers visualization superior to the supine, especially in obese and uncooperative patients and those with abundant bowel gas. We advocate that prone imaging be included routinely in renal DSA.
Assuntos
Angiografia/métodos , Rim/diagnóstico por imagem , Artéria Renal/diagnóstico por imagem , Técnica de Subtração , Adulto , Idoso , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PosturaAssuntos
Aspergilose Broncopulmonar Alérgica/diagnóstico , Adulto , Aspergilose Broncopulmonar Alérgica/diagnóstico por imagem , Aspergilose Broncopulmonar Alérgica/tratamento farmacológico , Aspergilose Broncopulmonar Alérgica/epidemiologia , Criança , Inglaterra , Humanos , Prednisona/uso terapêutico , Radiografia , Estados UnidosRESUMO
An unusual case of rounded atelectasis (RA) is described. This entity is likely to develop as a consequence of asbestos-induced pleural disease. The sine qua non of RA is a curvilinear tail extending from the inferior medial surface of a peripheral mass. Recognition of this "comet tail" prevents the necessity for surgery.
Assuntos
Atelectasia Pulmonar/diagnóstico por imagem , Amianto/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico por imagem , Atelectasia Pulmonar/etiologia , Atelectasia Pulmonar/patologia , Tomografia Computadorizada por Raios XRESUMO
In a review of 17 surgically proven cases of acute traumatic diaphragmatic hernia, a nasogastric tube had been inserted preoperatively in eight. In six of these patients the tube followed a characteristic course, indicating the diagnosis of gastric herniation into the left hemithorax. In four cases the passage of the tubing established the diagnosis; in the other two cases the diagnosis was suggested by plain films alone, but subsequent passage of the nasogastric tube provided confirmation.