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Patient dose data from across the UK were collated, and the information relating to full-field digital mammography systems were analysed, and compared with overall results for film-screen systems. For CR systems, the average mean glandular doses was 2.19 ± 0.07 mGy which was similar to the average for film screen systems 2.15 ± 0.01 mGy. The average patient dose for DR systems was 1.46 ± 0.02 mGy approximately 32% lower than for film screen systems. When different DR systems were compared, the Sectra MDM L30 and the Siemens Novation and Inspiration had the lowest average mean glandular dose, at 0.95 ± 0.02 mGy, 1.16 ± 0.05 mGy and 1.21 ± 0.07 mGy, respectively. It was shown that for DR systems the MGD to the standard breast was broadly correlated with the average MGD for oblique views of 50-60mm thick breasts, while the correlation for CR systems was much lower. [ABSTRACT FROM AUTHOR]

The optimization of image quality vs. patient dose is an important task in medical imaging. Maximal validity of optimization has to be based on clinical images. Simultaneous measurement of patient dose levels and image quality assessment is used to investigate possibilities for dose reduction and maintain image quality. The survey was conducted in a general hospital performing more than 60000 images annually and representing typical Serbian practice. For five most frequent diagnostic projections patient exposure was measured using kerma area product meter. Image quality was assessed by experienced radiologists using ˵European Guidelines on Quality Criteria for Diagnostic radiographic Images″. Following examination types were included into the survey: chest PA, chest LAT, pelvis AP, lumbar spine AP, lumbar spine LAT and pelvis. Comparing actual radiographic technique with recommended technique in European Guidelines, modification of practice was proposed and implemented and image quality was re-assessed. At least 10 adult patients were followed for each projection, before and after corrective actions. Large dose saving without compromising diagnostic information were found for some examination types, showing that this simple method is very efficient dose reduction tool in conventional diagnostic radiology. Also, need for staff training and difficulties related to practical implementation of optimization methods in Serbia were discussed. [ABSTRACT FROM AUTHOR]

The purpose of this work was an evaluation of organ doses and effective doses from kilovoltage (kV) Conebeam CT (CBCT) scans and from pairs of orthogonal kV image projections for two different treatment sites (a head and a pelvis). Measurements of organ doses were performed in an anthropomorphic Rando phantom by means of thermoluminescent dosimeters (TLDs). Irradiations were performed using On-Board Imager (OBI) and X-ray Volume Imaging (XVI) systems. [ABSTRACT FROM AUTHOR]

Reliability of methodologies for assessing patient doses is achieved through validation process. Absorbed dose in selected organs were measured in a Rando-Alderson phantom under chest examination conditions. Results were compared to dose values that were obtained by simulating the same conditions in the PCXMC® computational software. Both methodologies agreed in an acceptable manner. [ABSTRACT FROM AUTHOR]

Full field digital mammography is now becoming widespread in both the NHS and private healthcare sectors in the UK. In order to gain the most from the switch from film/screen to digital imaging, optimization of these systems has become of vital importance and even more so with the introduction of exotic spectra such as tungsten targets and silver filters. Protocols have now been published that give guidance on the commissioning and routine testing of full field digital mammography systems. These documents include remedial levels for the mean glandular dose to equivalent breasts for thicknesses of polymethylmethacrylate (PMMA) from 20 -70 mm and acceptable and achievable levels of image quality. At our site initial set-up of digital mammography systems is therefore based on dose measurements made with PMMA and image quality assessed with a contrast detail phantom and comparison with these limits. In order to confirm that these set-ups are appropriate patient dose surveys are also undertaken. We present results from a number of manufacturers΄ mammography systems comparing mean glandular doses to the standard breast measured with PMMA and clinical breast doses from patient dose surveys. Results show a different correlation for each manufacturer΄s system assessed between the two types of mean glandular dose measurement. Results from a GE system show less than 1% difference between the doses for 50 - 57 mm compressed breast thickness, whilst results for a Hologic system show a 50% difference. The work highlights how, for digital mammography systems, PMMA measurements of mean glandular dose alone give little information on the doses to real breasts and highlights the importance of carrying out a patient dose survey as soon as possible following the installation of a digital mammography system. [ABSTRACT FROM AUTHOR]

In the first ever survey of patient doses in Madagascar, image quality and patient doses were evaluated in 3 rooms of 2 hospitals in Madagascar as part of an International Atomic energy Agency (IAEA) project (RAF/9/033) using protocols and instructions by IAEA experts. Corrective actions were taken mainly in terms of field size and exposure parameters adjustment and data were recollected. Image quality improved in all 3 rooms (increase: 2-35%). Dose reductions in the range of 1 to 66% in terms of ESAK were found in different examinations investigated. The max reduction was found in chest examination. The comparison with IAEA guidance levels (GL) showed that patient doses (ESAK values) are lower than international values except for chest exam in one of the rooms of the hospital. Actions are being taken to extend measurements to a national level in the near future. [ABSTRACT FROM AUTHOR]

The main objective of this study was to estimate patient doses in conventional radiography and corresponding image quality in Zimbabwe, as part of an International Atomic energy Agency (IAEA) project (RAF/9/033). Three government hospitals and 5 private centers were selected with a total of 20 X-ray machines. Films were graded for a week at the radiographer and radiologist level. A radiologist was asked to assign A, B, C grade to films (A- clearly accepted without any remarks, B- accepted with some remarks and C- rejected). Quality Control (QC) was done including film processing and viewing areas. The QC included: 1) kVp consistency, 2) output linearity, 3) beam quality, 4) viewing box illumination and 5) darkroom tests. After QC and possible corrective actions, film grading was repeated. Results before QC and after QC were analyzed. Patient doses were determined in terms of Entrance Surface Air-Kerma (ESAK) for the following X-ray examinations: 1) Lumbar spine (L/S) AP and LAT, 2) Abdomen, 3) Pelvis, 4) Chest PA, 5) Skull AP and LAT. Patient doses were reevaluated after QC and corrective actions. There was image quality improvement from category B and C to category A after QC (1-12%). ESAKs in this study were much lower than IAEA GL for all examinations investigated. [ABSTRACT FROM AUTHOR]