RESUMO
The purpose of this study is to present a national survey that was performed in Greece for the establishment of national Dose Reference Levels (DRLs) for seven common adult Computed Tomography (CT) examinations. Volumetric computed tomography dose index and dose-length product values were collected from the post-data page of 65 'modern' systems that incorporate tube current modulation. Moreover, phantom dose measurements on 26 'older' systems were performed. Finally, the effective dose to the patient from a typical acquisition during these examinations was estimated. The suggested national DRLs are generally comparable with respective published values from similar European studies, with the exception of sinuses CT, which presents significantly higher values. This fact, along with the large variation of the systems' dose values that were observed even for scanners of the same type, indicates a need for further patient protection optimisation without compromising the clinical outcome.
Assuntos
Tomografia Computadorizada de Feixe Cônico/estatística & dados numéricos , Tomografia Computadorizada de Feixe Cônico/normas , Exposição Ambiental/análise , Exposição Ambiental/normas , Contagem Corporal Total/estatística & dados numéricos , Contagem Corporal Total/normas , Adulto , Carga Corporal (Radioterapia) , Tomografia Computadorizada de Feixe Cônico/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento/normas , Grécia , Guias como Assunto , Humanos , Masculino , Imagens de Fantasmas/normas , Doses de Radiação , Proteção Radiológica/normas , Proteção Radiológica/estatística & dados numéricos , Valores de ReferênciaRESUMO
The purpose of this study is to evaluate and compare the performance of 52 full field digital (FFD) and computed radiography (CR) mammography systems checked by the Greek Atomic Energy Commission with respect to dose and image quality. Entrance surface air kerma (ESAK) was measured and average glandular dose (AGD) was calculated according to the European protocol on dosimetry in mammography. The exposures were performed using the clinical protocol of each laboratory. The image quality was assessed by the total score of resolved phantom structures incorporated in an American College of Radiology accreditation phantom. The mean ESAK values for FFD and CR systems were 4.59 ± 1.93 and 5.0 ± 1.78 mGy, respectively, whereas the AGD yielded a mean value of 1.06 ± 0.36 mGy for the FFD and 1.04 ± 0.35 mGy for the CR systems. Considering image quality, FFD systems indicated a mean total score of 13.04 ± 0.89, whereas CR systems a mean total score of 11.54 ± 1.06.