RESUMO
OBJECTIVES: To evaluate the lowest radiation exposure threshold at which coronary calcium scoring (CCS) remains accurate. METHODS: A prospective study of 43 consecutive eligible patients referred for CCS underwent imaging in accordance with the manufacturer's recommended protocol. Dedicated software was used to generate 8 series of images simulating tube currents ranging from 20 to 300 mA. These images were randomised and read in blinded fashion to determine the lowest tube current at which the CCS remained accurate. The minimum mA was correlated with 6 different patients' biometric parameters: bodyweight, body mass index, AP and lateral thoracic diameters, average thoracic diameter and the scout attenuation coefficient (SAC). The 95% confidence interval for each parameter was used to calculate tube current threshold levels and hence stratified CCS protocols were derived. RESULTS: Spearman's correlation coefficients of the minimum tube current for the 6 parameters were: 0.66, 0.63, 0.65, 0.74, 0.77 and 0.86 respectively (p < 0.001). SAC offered the largest potential reduction in mean effective dose from 1.86 mSv to 0.88 mSv. CONCLUSION: CCS with at least 50% reduction in radiation exposure and below 1 mSv is feasible if CT scout projections are utilised effectively.
Assuntos
Calcinose/patologia , Cálcio/análise , Vasos Coronários/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Antropometria/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Fenótipo , Estudos Prospectivos , Doses de Radiação , Proteção Radiológica , Reprodutibilidade dos TestesRESUMO
Cavernous angiomas although relatively common lesions rarely reach a large size. They have a well documented association with AVMs, capillary telangiectases and venous angiomas but are not specifically associated with intracerebral aneurysms. We present a case of what we believe to be the 4th largest reported giant cavernous angioma to present in adulthood. This cavernous angioma also happened to be associated with a large intracerebral aneurysm, an association not previously reported. The sometimes confusing nomenclature of cavernous angiomas and other similar vascular malformations is also discussed.
