Radiation dose reduction on torax computer tomography (ct) according to patient features

By the increase of computed tomography (CT) which is used for diagnosis and treatment, also the dose patients receive during x-ray CT scan is have been increased. To reduce the harmful effects of radiation, reducing radiation dose which received by the patient is an important issue. Although there are many studies on computed tomography dose reduction, this topic is still under development. It is important to minimize the dose that patient is exposed and to achieve the highest quality of image. In this study, it is aimed to determine effects of the parameters of the patients on radiation dose and image quality. The study included 230 patients who received routine CT examination and this CT examination is achieved by using a 16 slices CT scanner, fixed 110 kilovolts, automatic variable milliamp and parameters of routine and shooting. The information that device provides automatically about dose; CT dose index (CTDI), doe length product (DLP) and the dose received by the patient, the parameters of CT examination (effective mAs, fix slice thickness, applied stable kernel), information of the patient (age, gender, body mass index) and the measurements (body-thickness-1, body thickness-2, chest wall thickness, bone density) was recorded. The effect of patients' personal characteristics on the amount of the dose that patient received and on the image quality was investigated by linear analysis. The functional relations between patients' features and output parameters was obtained and accordingly mathematical modelling was established.