Problems to be solved and possibilities for steps forward

Based on the foregoing, the first need in the following 3-4 years is handling of the first two levels of QC (=acceptance and status testing) in a unified manner. Accreditation of all the first three testing laboratories in this field in Hungary is based on standards IEC=EN=MSZ EN 61223-3 (acceptance testing) series. This fact is very fortunate from the point of view of comparability of test results, so it is very desirable to maintain this unity in the future, too.

Most of the mentioned standards, however, are not up-to-date from technical point of view any more. Exceptions are the mammography standard second edition of which appeared in 2007 and the CT standard validity of which is extended till 2015. For dental equipment, it is probable that after some years there will be an updated second edition of acceptance testing standard. However, standards for radiographic/fluoroscopic and DSA equipment were withdrawn in 2010, according to a 2009 decision of IEC. (As Hungarian – MSZ EN – standards they are still valid in the moment of writing these lines.)

There is an urgent need for finding the possibility of replacement of the withdrawn standards or their obsolete testing requirements by up-to-date ones in Hungary. It is obvious that the most proper and practical solution is to base upon unified recommendations accepted in EU. At present, however, such recommendation (document) exists for mammography only (see later). In other fields of radiology, a possible starting point may be the future second edition of document – in its earlier number – Radiation Protection 91 (RP91), final draft second edition of which is now under discussion on the EU website6. This document is not a “standard” but a “scientific publication” “only” (which is supported by EU but is not the official opinion of EU), but as – at least according to plans – will have a broad consensus (radiologists, physicists, manufacturers), accreditation bodies probably will accept it as a foundation of a testing laboratory accreditation without any further “validation”. It is important to emphasize that modern QC includes testing not only of radiation generation but also – with the aid of appropriate test objects – of quality of imaging and also patient doses.

There will be a problem, however, that scope of this document is not exactly the same as that of the standards to be withdrawn. Title of the document is “acceptability criteria”. So it does not give a complete QA system but – using QA terminology – the so-called suspension levels only. (Suspension level means a deviation which is unacceptable and gives a reason for prompt suspension of the use of the equipment. The equipment may be put into use again only if the deviation after servicing and adjustment does not exceed the suspension level.) The milder, so-called remedial levels are to be created and joined to the regulation on national level. Moreover, it is also not a simple thing to take these recommendations and go to perform measurements according to them as all part of them are to be considered individually, how it can really be applied in the practice in Hungary in the first step. The most important points of view to be considered are: present testing device inventory of the existing testing laboratories, real possibilities for maximum money and working time expenditures of testing and the possible maximum compatibility of new requirements with acceptance tests performed till now. A further problem of RP91 is that it does not describe testing procedures in detail but has dozens of references containing it. So for creating a QA system, applicable in the practice has the necessary condition, to evaluate (and above all to purchase, if needed) these referenced publications. Then the whole proposal must be formulated in such a manner which corresponds to a so-called “working instruction” of a QA system. In Hungary, it is not thought that make regulation stricter than the EU recommendation is, so Hungarian contribution is to be restricted – in addition to accepting and translating it into Hungarian – to elaboration of conditions of introduction, distributing it into steps and elaboration of rules of implementation, surveillance and penalizing.

There are two reasons to deal in the first step with QC of mammography. At first, most of mammography examinations are screening which are made on healthy persons. Radiation protection aspects of screening activities have stressed importance according to the directive of EU. In the literature – not accidentally – the highest proportion of scientific publications dealing with technology, physics and radiation protection aspects of radiology is connected with mammography. The other, undoubtedly practical reason is that at present only this topic has got the necessary conditions for regulation of a QA system. Foundation of the work is the section dealing with technical QC of the last (2004) edition of European Mammography Guidelines. This contains also QC test methods for digital (CR and DR) mammography. It would be harmonized with the Hungarian mammography screening protocol, Decree No. 31/2001. (X.3.) of the Minister of Health and laboratory practice so far. European recommendations for type testing of mammography equipment are also available in Hungarian.

---