Dose Datamed II Collective dose in the Portuguese/European population due to medical exposures. Pedro Teles CTN/IST

Transcription

1 Dose Datamed II Collective dose in the Portuguese/European population due to medical exposures Pedro Teles CTN/IST

2 The Dose Datamed II ( ) project Contract ENER/2010/NUCL/SI aimed at determining the collective dose in the European population due to medical exposures using a common methodology. o This project is the continuation of the Dose Datamed project which studied the different methodologies used for this evaluation in selected countries and established a common methodology which resulted in the publication of European Commission s Radiation Protection 154 European Guidance on Estimating Population Doses from Medical X-Ray Procedures and annexes ; o This project was successful in evaluating the collective dose in 36 European countries using this very same methodology, being the first time such a task is completed at a European level. lication/154.zip

3 RESULTS X-rays Overall collective effective dose due to x-rays per 1000 population per country Divided into groups: Group 1 (EU27 and EFTA countries): mansv/1000 pop.or 1.07 msv per caput. Group 2: (all European countries) mansv/1000 pop.or 1.05 msv per caput.

4 RESULTS Nuclear medicine Overall collective effective dose for nuclear medicine Divided into groups: Group 1 (EU27 and EFTA countries): mansv/1000 pop or msv per caput. Group 2: (all European countries) mansv or msv per caput.

5 DISCUSSION The overall per caput effective dose for all considered medical examinations (X-rays + NM) is of 1.13 msv (Group 1) and of msv (Group 2). The contribution of NM procedures to the total population dose is only of about 5 %. For x-ray procedures, the highest contribution to the collective dose is from computed tomography examinations, on average 57.0 % from the dose from all x-ray procedures (inter-country range 5,31 83,1 %). These values are about half of the recent value of collective effective dose estimated in Australia, and about one third of the corresponding value in the USA. However, comparing the results with an earlier estimation of population dose in Europe, in the DDM1 countries, per caput effective dose is on average about 30 % higher than estimated in DDMI

6 DISCUSSION part II While the average dose in Europe turned out to be relatively low, there are high variations of the results between countries indicating that there is a need for further studies and follow up of the trends, Relatively low value of population dose can be a good sign for a successful implementation of the justification and optimization principles in radiation protection, But it can also be related to the lack of imaging resources, Or due to social-economical-cultural factors, On the other hand, a high collective dose value leads to doubts over whether the justification and optimization principles are properly implemented.

7 CONCLUSIONS, future work First time such task is implemented on such a broad scope, using a common methodology; The project was successful and an excellent startup point for many countries to implement such studies (even from a bottom-up approach ) Uncertainties : although the overall uncertainty was estimated to be ~10%, the uncertainties in each country can be much higher or even much lower; Each country is different. Although a common methology helps in estimating values for doses, the high variations in frequencies of exams and estimated doses is a sign that perhaps there are shortcomings in the methodology; Top 20? Top 50? Which are which?

8 Dose Datamed 2 Portugal?? The Portuguese reality Dose estimation in the population is a legal obligation(article 14 of Decree- Law165/2002); Portugal does not have a tradition in population evaluation, and this was an excellent starting point; There is, in fact, a persisten lack of radiological and dosimetric data which can be transmitted to international bodies (European Commission, UNSCEAR, WHO.), and even confusion in who is who in the radiological landscape in Portugal!!!! Transmitting in useful time the data relative to the Portuguese participation in the Dose Datamed 2 was therefore of the utmost importance; This was performed within the established deadlines (ups and downs; We hope that the Portuguese participation in this project can serve as a good beginning to a new attitude in relation to this theme. Finally, this study was also useful in performing a charachterisation of the Portuguese Health system and available technology.

9 DOSE DATAMED PORTUGAL CONSORTIUM ICNAS Instituto de Ciências Nucleares Aplicadas à Saude

10 Methodology Dose Datamed Portugal consortium According to article 14 of Decree-Law 165/2002 doses in the population must be estimated periodically, having ITN a preponderant role in this evaluation. RP 154 Methodology Charachterisation of Portugal s Health System top 20 frequencies Nuclear medicine examinations (frequencies, activities/exam) top 20 dose evaluation

11 NUCLEAR MEDICINE FREQUENCY DATA number of exams per 1000 population Bone Heart Thyroid Lung Kidney TOTAL PORTUGAL (2010) ,1 0, UK ( )* 3 2 0, Switzerland (2004)* Germany (2002)* Belgium ( )* Belgium Germany Switzerland UK PORTUGAL Bone Heart Thyroid Lung Kidney remainder 0% 20% 40% 60% 80% 100% frequency distribution (%) * Data for other countries from RP 154

12 NUCLEAR MEDICINE FREQUENCY DATA Total annual collective dose 840 mansv ou 0,080 msv/caput Tomografia de Emissão de Positrões - Estudo de Corpo Inteiro com TC diagnóstico; 2,2 Cintigrafia da Tiroideia ; 2,5 Angiografia de Radionuclideos em Equilíbrio ; 3,7 Cintigrafia de Perfusão Miocárdio - Tálio; 2,0 Restantes; 5,2 Cintigrafia Óssea; 20,8 Cintigrafia de Perfusão Miocárdio (Esforço) - MIBI; 5,2 Cintigrafia de Perfusão Miocárdio (Esforço) - Tetro; 18,2 Cintigrafia de Perfusão Miocárdio (Repouso) - MIBI; 5,5 Tomografia de Emissão de Positrões - Estudo de Corpo Inteiro ; 9,6 Cintigrafia de Perfusão Miocárdio (Repouso) - Tetro; 16,9 Myocardial perfusion(mibi + Tetrafodmina): 47.8% Bone imaging: 20.8% PET/PET+CT : 11.8 % (9.6% for PET and 2.2% for PET+TC)

13 X-RAY (TOP 20) FREQUENCY DATA number of exams per 1000 population 1. Chest/thorax 5. Mammography 13. CT Head 11. IVU TOTAL PORTUGAL (2010) , Considering that the top 20 correspond to 50 e 75% of total examinations (RP 154) UK ( ) Switzerland (2004) Germany (2002)

14 X-RAY (TOP 20) COLLECTIVE DOSE DATA The top 5 exams are all CT, These 5 exams contribute 67% to the collective dose.

15 CONCLUSIONS Nuclear Medicine In 2010, the annual collective dose in the Portuguese population due to NM exams is of 0,08 msv/caput; In 2010 there was a very high incidence of cardiac examinations (Myocardial Perfusion) in comparison with the rest of Europe PET exams are in 4th place and contribute ~11% to the total collective dose Top 20 exams For the top 20 exams the total collective dose in Portugal was of 0,9 msv/caput; CT examinations account for ~70% of the total annual collective dose; Conventional radiography, as well as fluoroscopy, despite representing more than 80% of total annual examinations, only account for22% of the total annual collective dose in the Portuguese population. Coronary examinations only account for 4% of the total exams.

16 It is the first time such a study is undertaken in Portugal in such a broad scope; The total annual collective dose in Portugal, in 2010, was of e 1mSv/caput, placing Portugal in a group of countries with a medium to high exposure to medical ionising radiations. The obtained value is twice as high as the value obtained in a pioneering study performed in 1992, even taking into account the uncertainties (R Serro etal, RPD) The DDM Portugal believes that this exercise should be undertaken in Portugal on a periodical basis. The participation in the European project was a one-off event. The obtained results have a high uncertainty and should be ameliorated. WE HOPE THAT THIS WORK CAN CONTRIBUTE TO A CHANGE OF POSTURE IN PORTUGAL IN RELATION TO THE USE OF IONISING RADIATION IN MEDICINE.