It is inadvertently assumed that tertiary scatter radiation is negligible.
there isn’t a simple method to easily estimate the tertiary scatter levels for specific facilities.
the main goal of this study was to quantify the tertiary scatter radiation in a CT room through a suitable method,
especially considering the increases in workloads of interventional CT procedures.
Methods and materials
Instrumentation The materials used in order to conduct this research were: 1 computed tomography (CT) equipment SIEMENS ® SOMATOM ® EMOTION ® 16 1 water phanton (25 liters) 1 lead shield (thickness of 20 mm) 1 radiation detector (Atomtex AT1123) 11 thermoluminescent dosimeter 1 Full body anthropomorphic phantom Variables In this study,
namely in the experimental fase,
there were considered two types of variables: · Independent variables: acquisition parameters of the image (mAs,
The Fig. 5 represents the tendency of the dose rate (mSv/s) of the scattered radiation according to the orientation of the detector and comparison between mean dose rates with and without lead protection.
We observed an abrupt decrease of the dose rate values when applied the lead protection (grey line). The highest value of the dose rate was measured without lead protection and with the detector directly faced to the gantry,
in 0º position.
With the lead protection the major contribution of...
the tertiary radiation is significant and actually contributes to the dose rate with 3,6% of all the scattered radiation considered in the defined place as the position occupied by the individual occupationally exposed in the CT room. The major contribution of the tertiary radiation comes from the dispersion of the radiation that occurs in the roof,
contributing with 88,4% in the dose rate.
This value decreased abruptly when a lead protection was placed,
which blocked the...
Rui Almeida (MSc),
Professor in the Medical Imaging and Radiotherapy Department,
Health School - University of Algarve,
Radiographer in Centro Hospitalar do Algarve,
Researcher in CICS.NOVA (Universidade Nova de Lisboa – Pólo de Évora) and Member of the Studies Center in Healthcare (CES-ESSUALG).
E-mail: firstname.lastname@example.org. Tel: +351289800100 Ana Calafate (BSc),
Collaborator in the Medical Imaging and Radiotherapy Department,
Health School - University of Algarve,...
Adam Rouilly Simulators,
Anatomical models and charts for clinical skills and training.
(2010). Adam Rouilly,
Models and Simulators for Clinical Skills and Practice .
AR10A Radiographic Positioning Doll.
England. Atomtex (2013). Portable Dosimeters: AT1121,
AT1123 X-RAY and Gamma Radiation Dosimeters. Disponível em http://www.atomtex.com/en/products/portable-dosimeters/at1121-at1123-x-ray-and-gamma-radiation-dosimeters Baert,