Computed tomography (CT) has been widely used in clinical diagnosis. It is important to estimate radiation dose and perform image quality assurance procedures for CT scans. In this study, nMAG gel dosimeters were used to simultaneously measure the 300-mm weighted CT dose index (CTDI) and slice sensitivity profile (SSP) for multiple detector CT (MDCT). Magnetic resonance imaging (MRI) was perfor...

There are 90 CT units operating in Serbia, with tenfold increase in the last decade, resulting with annual total of approximately 350000 procedures. The objective of this paper is to assess typical patient dose from adult and paediatric CT examinations. Initially, three hospitals (two general hospitals performing examination of adults and a dedicated paediatric hospital) were enrolled into the ...

background : medical x-rays are the largest man-made source of public exposure to ionizing radiation. while the benefits of computed tomography (ct) are well known in accurate diagnosis, those benefits are not risk-free. ct is a device with higher patient dose in comparison with other conventional radiation procedures. objective: this study is aimed at evaluating radiation dose to patients from...

chamber.The concept of CTDI is still the basis for dosimetry at modern CT scanners, although the assessment of CTDI in phantoms has been the subject of much discussion and many revisions were required since its initial definition. A fundamental revision was for example needed when helical CT was introduced and the concept of pitch had to be taken into account. With the introduction of diagnosti...

The aims of this study were to investigate the frequency of computed tomography (CT) examinations for paediatric patients below 15 y of age in 128 CT facilities in 28 developing countries of Africa, Asia and Eastern Europe and to assess the magnitude of CT doses. Radiation dose data were available from 101 CT facilities in 19 countries. The dose assessment was performed in terms of weighted CT ...

Computed tomography (CT) dosimetry normally uses an ionization chamber 100 mm long to estimate the computed tomography dose index (CTDI), however some reports have already indicated that small devices could replace the long ion chamber to improve quality assurance procedures in CT dosimetry. This paper presents a novel dosimetry system based in a commercial phototransistor evaluated for CT dosi...

Diagnostic reference levels (DRLs) were established for 21 indication-based CT examinations for adults in Switzerland. One hundred and seventy-nine of 225 computed tomography (CT) scanners operated in hospitals and private radiology institutes were audited on-site and patient doses were collected. For each CT scanner, a correction factor was calculated expressing the deviation of the measured w...

Introduction: Nowadays, the demand for CT-scan is increased, and this issue has become a critical subject in radiation protection, because of the risk of cancer especially for children. The quality assurance of CT images is a necessary factor that can effect on children dose. The CT dose index is an important dosimetry index in CT-Scan dosimetry. The purpose of this study is t...

Beam hardening filters have long been employed in X-ray Computed Tomography (CT) to preferentially absorb soft and low-energy X-rays having no or little contribution to image formation, thus allowing the reduction of patient dose and beam hardening artefacts. In this work, we studied the influence of additional copper (Cu) and aluminium (Al) flat filters on patient dose and image quality and se...