QUALITYASSURANCE IN CT WITH THE BELGIAN PROTOCOL AND THE NEW EUROPEAN ACCEPTABILITY CRITERIA Hilde Bosmans 1,2, *, Kim Lemmens 1,2 , Jim Malone 3 and Raymond Oyen 1 1 Department of Radiology, University Hospitals Leuven, 3000 Leuven, Belgium 2 Working Group ‘Radiology’ of the Belgian Hospital Physicists Association, 1950 Kraainem, Belgium 3 Trinity College Centre for Health Sciences, Dublin 8, Ireland *Corresponding author: hilde.bosmans@uzleuven.be In a working group of the Belgian Hospital Physicists Association (BHPA), a new protocol has been developed for compre- hensive 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 allowautomated 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 suc- cessor RP 162. The results of the tests of the BHPA protocol are discussed in the light of the acceptabilitycriteria 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. INTRODUCTION The purpose of the European Commission (EC) publication in the Radiation Protection serie RP 91 (1) is to specify the minimum standards of per- formance for radiological (including radiotherapy) and nuclear medicine equipment. The document is, among other things, a helpful guideline for the medical physics expert (MPE), especially if local regulation relies upon it. This is the case in Belgium, for example, with quality assurance (QA) tasks in computed tomography (CT), there is no other docu- ment that obliges the MPE to perform more tests than what is prescribed in that document. As a con- sequence, many MPEs restrict their tasks to an annual verification of scanner performance to the suspension levels in the RP91. The definition of the MPE in the Euratom 97/43 Directive (2) imposes additional tasks on medical physicists. They should act or give advice on patient dosimetry, on the development and use of complex techniques and equipment, on optimisation and on QA, including the quality control (QC), and on other matters relating to radiation protection during medical exposures. In the Belgian Hospital Physicists Association (www.bhpa.eu), a working group was therefore estab- lished with the aim to produce a protocol that can guide several of these tasks. If the text is adopted in the national law, the authors expect all MPEs to become involved in all the tasks of medical physics. The working group concluded that ‘passing suspen- sion levels’ is a necessary but not a sufficient basis to ensure the appropriate quality in the CT room. The group aimed for a protocol with a set of tests that allows verification that: (1) the CT scanner is technically adequate, with exposure-related parameters within reasonable limits; (2) patient protocols are preprogrammed with ac- ceptable, up-to-date exposure settings; (3) all technical parameters displayed at the console are correct; (4) the MPE learns enough about the system’s dose setting options to be able to discuss items such as dose reduction with the responsible radiolo- gists or with the CT clinical team and to be able to launch projects in the frame of QA; (5) automated CT dosimetry from DICOM header tags or from the patient dose report is indicated. Several existing QA protocols and standards were studied to compile a list of tests and limiting values. (3 – 7) In parallel with this, new tests are pro- posed and explored where established protocols lacked evaluation methods. Most often this was the case for the testing of newer options on the scanner and/or related to the aim to confirm appropriateness of available input data for automated patient dosim- etry. A comprehensive test was compiled and made available to the public. (8) The Federal Agency of this study is transposing these improvements into a national legislation. The set of tests were subdivided into: # The Author 2012. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com Radiation Protection Dosimetry (2013), Vol. 153, No. 2, pp. 197–205 doi:10.1093/rpd/ncs281 Advance Access publication 11 December 2012 at Trinity College Dublin on April 1, 2013 http://rpd.oxfordjournals.org/ Downloaded from