Hospital Physicists Association Research Articles

Quality assurance in CT with the Belgian protocol and the new European acceptability criteria

In a working group of the Belgian Hospital Physicists Association (BHPA), a new protocol has been developed for comprehensive testing of computed tomography scanners. The tests were selected to verify if the scanner is technically adequate, if preprogrammed patient protocols are up-to-date, and if exposure values displayed at the console are sufficiently correct. In addition, they will ensure that the participating medical physics expert (MPE) gets a full understanding of the system to enable him/her to guide optimization processes and allow automated patient dosimetry. Several new test procedures had to be developed. The tests go beyond the criteria identified in the EC guidance document radiation protection (RP) 91 and its successor RP 162. The results of the tests of the BHPA protocol are discussed in the light of the acceptability criteria in RP 91 and RP 162. It is concluded that the ensemble of tests in the BHPA protocol and in RP 162 provide very useful information on the scanner and, more importantly, how the scanner is being used on patients. It is expected that major optimization studies will be triggered by annual testing based on the new documents.

EFOMP: the European roof for medical physics.

Medical Physics is a field of applied physics and as such a comparatively young discipline. The roots of Medical Physics go back to the application of ionising radiation in diagnostics and therapy in the beginning of the last century. Between the years 1950 and 1970, the increasing importance and specialisation of Medical Physics led to the foundation of Medical Physics societies in most European countries. Currently, nearly all European states have Medical Physics societies, with more than 6,000 personal memberships. Due to an initiative of the English hospital physicists association (HPA), there was a suggestion in 1979 to form a European Roof organisation that included all national societies. In May 1980, this proposal led to the foundation of the “European Federation of Organisations in Medical Physics” (EFOMP) as an association of the European national societies in Medical Physics, which, in the EFOMP nomenclature are called “National Member Organisations (NMOs)”. Starting with 14 foundation member states, EFOMP today has 35 NMOs, which are not only restricted to the area of the European Community (EC), but also includes non-EC-member states such as Switzerland, and in the meanwhile also includes most East-European countries, and associated countries like Israel, Algeria and South Africa (Figure 1). The reason for the foundation of a European roof organisation was due to the fact that Medical Physics was practiced in the different states in quite a different way. In European countries, there was a large variation in education and training that was very differing or even missing regulations, and a very underdeveloped scientific collaboration between the countries.

Authors' reply

CorrespondenceAuthors' replyB M MooresB M Moores1Co-ordinator, Radiological Unification Strategies [RADIUS] Group, EC Radiation Protection Research ProgrammeSearch for more papers by this authorPublished Online:13 Feb 2014https://doi.org/10.1259/bjr/71189157SectionsPDF/EPUBFull Text ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InEmail About"Authors' reply." The British Journal of Radiology, 79(940), pp. 357–358 References 1 Shrimpton PC, Wall BF, Jones DG, Fisher ES, Hillier MC, Kendall GM. A national survey of doses to patients undergoing a selection of routine x-ray examinations in English hospitals. NRPB-R200. Chilton, UK: National Radiological Protection Board 1986. Google Scholar2 National protocol for patient dose measurements in diagnostic radiology. Chilton, Didcot: National Radiological Protection Board 1992. Google Scholar3 Rowley KA, Hill SJ, Watkins R, Moores BM. An investigation into the levels of radiation exposure in diagnostic examinations involving fluoroscopy. Br J Radiol 1987;60:167–73. Link ISI, Google Scholar4 Gallini RE, Belletti S, Berna V, Giugni U. Adult and child doses in standardised x-ray examinations. Radiat Prot Dosim 1992;43:41–7. Crossref ISI, Google Scholar5 Zankl M, Fill U, Petoussi-Henss N, Regulla D. Organ dose conversion coefficients for external photon irradiation of male and female voxel models. Phys Med Biol 2002;47:2367–85. Crossref Medline ISI, Google Scholar6 Kramer R, Vieira JW, Khoury HJ, Lima FRA, Fuelle D. All about MAX: a male adult voxel phantom for Monte Carlo calculations in radiation protection dosimetry. Phys Med Biol 2003;48:1239–62. Crossref Medline ISI, Google Scholar7 Kramer R, Khoury HJ, Vieira JW, Loureiro ECM, Lima VJM, Lima FRA, et al. All about FAX: a female adult voxel phantom for Monte Carlo calculation in radiation protection dosimetry. Phys Med Biol 2004;49:5203–16. Crossref Medline ISI, Google Scholar8 Pascoal A, Patel R, Lawinski CP, Tabakov S. Optimization of tube voltage and dose for digital chest radiography – a study addressing patient size. In: Proceedings of UK Radiological Congress, 6–8 June, 2005. London, UK: British Institute of Radiology 2005. 2 Google Scholar9 Wall BF, Rae S, Darby SC, Kendall GM. The NRPB survey: methods and results. Dosimetry in diagnostic radiology, CRS 40. Chapter 6, 44–55. The Hospital Physicists Association 1984. Google Scholar10 Goodenough DJ. Lessons learned in radiology. Proceedings of an international conference held in Malaga, Spain, 26–30 March 2001, 145–155. International Atomic Energy Agency 2001. Google Scholar11 Faulkner K, Moores BM. Radiation dose and somatic risk from computed tomography. Acta Radiologica 1987;28:483–8. Crossref Medline ISI, Google Scholar12 Harrison RM. Dose measurement in vivo and in vitro. CRS 40. Chapter 2, 8–17. The Hospital Physicist's Association. 1984. Google Scholar13 TGR 32 Measurement of the performance characteristics of diagnostic X-ray systems used in medicine. Part 1: X-ray tubes and generators. The Hospital Physicist's Association. 1984. Google Scholar Previous article Next article FiguresReferencesRelatedDetails Volume 79, Issue 940April 2006Pages: 275-361 © The British Institute of Radiology History ReceivedNovember 18,2005RevisedJanuary 04,2006AcceptedJanuary 11,2006Published onlineFebruary 13,2014 Metrics Download PDF

Book review

This report will be of interest to all nuclear medicine and physics staff who use gamma cameras and associated computer systems. It has been written by a group of experts in the field of nuclear medicine quality control, namely the Radionuclide Topic Group of the Institute of Physical Sciences in Medicine, and replaces the Hospital Physicists Association's earlier report (TGR27) on the theory, specification and testing of Anger type gamma cameras, published in 1978.

Memorandum from the Institute of Physical Sciences in Medicine

At present, the dosimetry of low- and mediu-energy X-radiation for radiotherapy purposes in the UK is based on the method recommended in International Commission on Radiation Units and Measurements (ICRU) Report 23 (1973), and incorporated into the current Hospital Physicists' Association (HPA) code of practice (1983). The essential points are summarized here using the same symbols and units as in the code of practice. For an X-ray beam between 150 kV and 300 kV (0.5 mm Cu and 4 mm Cu half-value layer (HVL)), ICRU recommended that output measurements should be made using an ionization chamber with its centre 5 cm deep in a water phantom. Absorbed dose is given by: or by: where D = absorbed dose to water in grays at the position of the centre of the chamber, with the chamber replaced by water, R = instrument reading, corrected to the same standard ambient conditions as the calibration factor, N k = calibration factor to convert the instrument reading to air kerma in grays for standard ambient conditions (at present 20°C, 1013 mbar, and 50% RH for calibrations at NPL), N x = calibration factor to convert the instrument reading to exposure in röntgens for standard ambient conditions, F = a conversion factor, in rad/röntgen, which depends on the HVL of the X-ray beam being used.

Performance assessment of X-ray image intensified television fluoroscopy systems in New Zealand.

The protocol for image intensifier (II) quality assurance recommended by the UK Hospital Physicists' Association (HPA) and the UK Department of Health and Social Security has been adapted for use in New Zealand for assessment of such systems. Test objects were constructed at the National Radiation Laboratory to match the specifications of those recommended by the HPA. Over 100 individual surveys have been made and, in a few cases, machines have been surveyed several times. Results are summarized in terms of key parameters: II input dose rate, low-contrast detectability, contrast-detail performance and limiting resolution. These are given as mean and standard deviation, and also as good, average or poor. Video waveforms, conversion factors and modulation transfer functions have also been determined on a number of systems. In several cases, video voltages were found to be seriously maladjusted.

Dynamic monitoring of output on a superficial X-ray set using a solid-state device.

A solid-state output monitor has been constructed and tested on a Philips RT100 superficial X-ray set operating at 55, 70 or 100 kVp. The device is useful to radiographers, technicians, engineers and physicists and can be easily assembled and fitted with a minimum amount of machine downtime. Recommendations concerning control of X-ray doses for superficial therapy are outlined in a Radiotherapy Apparatus Safety Measures Panel (RASMP) document (Department of Health and Social Security (DHSS), 1975). These recommendations do not require the use of a dose-rate monitor but the Code of Practice, Section 4.2.10 (ii) states that, where a monitor is not fitted, the output under standard conditions should be checked frequently, preferably at least once each working day (Her Majesty's Stationery Office (HMSO), 1972). The latter statement is repeated in paragraph 344 of the consultative document of Draft Guidance Notes for the Protection of Persons against Ionizing Radiations Arising from Medical and Dental Use (HMSO, 1983). The Ionizing Radiations Regulations 1985 do not contradict this statement (HMSO, 1985). The need for a dose-rate monitor in a superficial X-ray set is highlighted in a Hospital Physicists' Association (HPA) Radiation Protection Topic Group Newsheet (HPA, 1986) describing a situation in which an incorrect filter had been inserted in the beam. Routine measurement of output can be done by radiographers using locally constructed equipment (as described, for example, by Tranter et al (1978)) but will only indicate output whilst the detector is in position.

Science and health care-whence and whither

The 1986 Association Lecture of the Hospital Physicists Association is concerned with the application of physical science to the diagnosis, treatment and prevention of human disease. The author of this lecture attempts to show how patients have benefited in health care from the development and application of science generally and looks beyond its help in diagnosis and treatment of illness and bodily defects to its relation to and its possibilities in preventive medicine and to possible improvements in the quality of life.

History of the Hospital Physicists Association 1943–1983

History of the Hospital Physicists Association 1943–1983

Radionuclide techniques in clinical investigation by P W Horton. Medical physics handbooks 12. Adam Hilger Ltd., Bristol, in collaboration with the Hospital Physicists Association. June 1982 × + 172 pp. £13.95 ISBN 0–85274–503‐6

Radionuclide techniques in clinical investigation by P W Horton. Medical physics handbooks 12. Adam Hilger Ltd., Bristol, in collaboration with the Hospital Physicists Association. June 1982 × + 172 pp. £13.95 ISBN 0–85274–503‐6

A broader spectrum of therapy

Some applications of electric and magnetic fields in medicine', organised by the Hospital Physicists Association, was held on 24th October 1980 at the University of Sheffield Medical School.

Predictive physiological measurement

The joint Physiological Measurement Topic Group of the Biological Engineering Society and the Hospital Physicists Association held a Work in Progress meeting at St Bartholomew's Hospital, London, on Friday 23rd January 1981. The topic for the day was “Predictive Physiological Measurement”.

Durham ultrasonics meeting a success

‘Physics in medical ultrasoun’ organised under the auspices of the Hospital Physicists Association and the British Medical Ultrasound Society was held on 13-14th April 1981 in Durham.

Book ReviewA Guide to Medical Ultrasonics and Acoustics. Hospital Physicists Association Scientific Report Series, No. 10, pp. 44, 1977. (Hospital Physicists Association, London), £2·00.

Acoustics is still a subject in which many medical physicists feel ill at ease and this little booklet is designed to introduce them to some of the basic ideas and to provide them with the beginnings of a bibliography.

Book reviewRadiation Dosimetry Data. Catalogue 1976 (I.A.E.A., Vienna). Free.

This catalogue which now appears in its third edition originated from the diagrams and data scheme prepared originally by the Hospital Physicists Association. The present edition reflects the decline in the use conventional energy X rays in favour of megavoltage X rays, telecobalt, and telecaesium equipment, and the replacement of radium containers by the same radioisotopes in brachy-therapy.

2nd Annual Joint Meeting of the Biological Engineering Society and the Hospital Physicists Association

2nd Annual Joint Meeting of the Biological Engineering Society and the Hospital Physicists Association

Book reviewThe testing of radiation protection instruments used for the monitoring of surfaces contaminated with radioactive materials, 10pp. HPA Report Series No. 11, 1974 (London, The Hospital Physicists Association.), £1.

Book reviewThe testing of radiation protection instruments used for the monitoring of surfaces contaminated with radioactive materials, 10pp. HPA Report Series No. 11, 1974 (London, The Hospital Physicists Association.), £1.

Book reviewA Guide to Medical Ultrasonics and Acoustics, 52 pp. HPA Report Series No. 10, 1973 (London, The Hospital Physicists Association), £1.

In line with the general purpose of the series, this report has been prepared “as a guide to those wishing to start in the field of medical ultrasonics”. It interprets this brief very modestly and is written in the form of eight, 500-word essays, by a variety of authors, on subjects ranging from ultrasonic measurements to audiology, through imaging systems, Doppler methods, safety, surgery and physiotherapy applications.

Book reviewsH.P.A. report Series 9. The Role of the Radiological Protection Adviser. Diagnostic X-ray Protection pp. 91, 1972, (London, Hospital Physicists Association), £2·00

As is pointed out in the preface of this report “while it is desirable that the RPA should be a senior and experienced physicist this has not always proved possible”. The report therefore is “primarily to help those RPAs who have had little experience of diagnostic radiology or radiation protection work”.

Book reviewsThe Physics of Radiodiagnosis. 1973 (London, The Hospital Physicists Association).Report A:An introduction to diagnostic radiological systems. 40 pp. H.P.A. Report Series No. 6. £2.Report B:Measurements referring to diagnostic X-ray Beams. 36 pp. H.P.A. Report Series No. 7. £2.Report C:The assessment of Image Intensifier and Television System Performance. 31 pp. H.P.A. Report Series No. 8. £2.

These short reports were prepared by the diagnostic radiology topic group of the H.P.A. The standing of the members of the topic group is sufficient to guarantee that the reports are of a very high standard. Only a very few experts working in this field would fail to learn much by the study of these reports and they will be undoubtedly of great value to all working in the fields covered, whether physicists, engineers, technicians or those radiologists and radiographers who take a serious interest in these matters.