RESUMO
The aim of this study is to investigate the possibility of replacing the standard CTA protocol for peripheral arteries with a low dose CTA protocol without affecting the diagnostic image quality. Therefore a single centre retrospective study was conducted involving 200 exams of patients undergoing lower limb angiography. All exams were performed on a 64-row detector CT and the vascular density, muscle density, noise and radiation dose of each image were assessed. The subjective image quality was evaluated additionally by an experienced radiologist. Significant differences were observed in radiation dose and image quality between the standard CTA protocol and the lower dose CTA protocol. No differences were found between objective and subjective image quality. Using 80kVp instead of 120kVp as the tube voltage for lower limb CTA reduces the radiation dose without affecting the diagnostic image quality.
