RESUMO
Diagnostic accuracy was evaluated in a signal detection experiment that used low-contrast acute lesions in a living dog model. At the high levels of certainty normally used by radiologists, rare earth screen-film systems provided accuracy comparable to that of a reference calcium tungstate screen-film system. Additionally subjective image quality evaluation for a given imaging task (clinical pediatric anterior-posterior chest films) based on visualization of anatomic landmarks and physical parameters has been conducted for several rare earth and one calcium tungstate screen-film system. The correspondence of subjective physical ranking with physical and psychophysical measurements was investigated. Evaluating the visualization of anatomic parameters can provide a clear and objective distinction among systems with comparable physical and psychophysical properties.
Assuntos
Intensificação de Imagem Radiográfica , Filme para Raios X , Ecrans Intensificadores para Raios X , Animais , Biometria , Erros de Diagnóstico , Cães , Estudos de Avaliação como Assunto , Metais Terras Raras , Intensificação de Imagem Radiográfica/instrumentação , Radiografia TorácicaAssuntos
Olho/diagnóstico por imagem , Doenças Retinianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Pré-Escolar , Diagnóstico Diferencial , Neoplasias Oculares/diagnóstico por imagem , Humanos , Lactente , Masculino , Retina/patologia , Doenças Retinianas/patologia , Retinoblastoma/diagnóstico por imagemRESUMO
Computed tomography (CT) has fundamentally altered our approach to the initial evaluation and follow-up of patients with spina bifida. This safe and simple, non-invasive diagnostic technique has doubtlessly encouraged earlier diagnosis of clinically significant problems associated with spina bifida and has greatly facilitated the day-to-day management of those patients with documented disorders. CT is now effectively employed as a screening measure for both intraspinal and intracranial problems and can be relied upon to objectively guide and monitor elected modes of therapy.
Assuntos
Espinha Bífida Oculta/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tecido Adiposo/diagnóstico por imagem , Derivações do Líquido Cefalorraquidiano , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Pressão Intracraniana , Masculino , Meningocele/diagnóstico por imagemRESUMO
Clinical and laboratory observations were made in three children with isosexual precocity. None of the patients showed abnormalities in neurological or visual-field examinations although one patient had arrested hydrocephalus and a head circumference greater than the 98th percentile for her age and another patient had a history of seizures. Roentgenograms of the skull were normal in all patients. Cranial computerized tomography (CT) identified a lesion in each patient. We believe that craniel CT should be performed in any patient with isosexual precocity in whom a specific cause is not evident or in whom a cerebral cause is suggested even though the patient may be otherwise normal. Cranial CT is a safe, accurate, and noninvasive technique.
