Norsk telleprosjekt basert på 2008 del av europeisk studie basert på RP154 og TOP20 metodikk

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1 Norsk telleprosjekt basert på 2008 del av europeisk studie basert på RP154 og TOP20 metodikk Hilde M. Olerud, PhD Seksjonssjef Statens strålevern 1. Amanuensis II UiO, Fysisk institutt Novembermøtet 2009, Gardermoen

2 United Nations Scientific Committe on the Effects of Atomic Radiation (UNSCEAR) UNSCEAR, etablert i 1955 Vurderer all tilgjengelig litteratur innen kilder for ioniserende stråling og biologiske effekter av slik stråling Publiserer en oppsummering og konklusjon på dagens viten på området (ca 5 års intervall) Faktarapporter som gir grunnlag for råd og anbefalinger EFFECTS Annex G Low doses 563 referanser SOURCES: Annex D Medical exposures 1115 referanser

3 Germany Luxembourg Estonia Croatia Radiology in Norway ( ) Lithuania Czeck Republic Portugal Slovakia Switzerland Norway Finland Poland Ukraine Netherland Bulgaria Sweden Denmark UK Hungary Romania Slovenia Norway 910 (742 X-ray based) examination per 1000 inhab. 72% in public sector, 28% in private sector During the last decade 16% increase in total number MRI frequency 11 US increased by 40% CT frequency 2 X-rays decreased by 10% 1.1 msv per caput CT contribute to 59% of the collective effective dose No. X-ray exams per 1000 inhabitants

4 DOSEDATAMED TREN/04/NUCL/S Barry Wall (chair), David Hart Abbas Aroua, Philipp Trueb Bernard Aubert, Pascale Scanff, Phillippe Pirard, Hélène Beauvais Elke Nekolla, Jurgen Griebel Paul Stoop, Els Meeuwsen, Marco Brugmans Hilde Olerud, Ingelin Borretzen Wolfram Leitz Ferid Shannoun Hanne Waltenburg, Peter Grøn Alfred Lecluyse, Harrie Mol UK Switzerland France Germany Netherlands Norway Sweden Luxembourg Denmark Belgium

5 European Commission RADIATION PROTECTION N o 154 European Guidance on Estimating Population Doses from Medical X-ray procedures EC Report in the RADIATION PROTECTION series. Annex 1 DD Report 1 Review of recent national surveys of population exposure from medical X-rays in Europe Annex 2 DD Report 1 (a) Review of national surveys of population exposure from nuclear medicine examinations in eight European countries available as a pdf files on the EC DGTREN Radiation Protection website cation_en-htm

6 EC RP N o 154 Annex 1 DD Report 1 REVIEW OF RECENT NATIONAL SURVEYS OF POPULATION EXPOSURE FROM MEDICAL X-RAYS IN EUROPE 1. Introduction 2. History of population dose assessments from medical x-rays in Europe 3. National arrangements and responsibilities 4. National regulatory frameworks 5. National healthcare systems in 10 European countries 6. National strategies for assessing population dose from medical x-rays 7. Methods for assessing the frequency of x-ray examinations 8. Methods for assessing patient doses 9. Results 10. Discussion 11. Conclusions 12. References Appendix 1: Recent national surveys of population dose from medical x-rays Appendix 2: Accuracy of population dose estimates Appendix 3: Tables showing detailed frequency and patient dose results for the Top 20 Exams in each country Look back explain differences!

7 EC RADIATION PROTECTION N o 154: EUROPEAN GUIDANCE ON ESTIMATING POPULATION DOSES FROM MEDICAL X-RAY PROCEEDURES 1. Introduction 2. Purposes for making population dose estimates for medical x-rays and the dose quantities used 3. Guidance on assessing frequency of x-ray examinations 3.1 How to categorise examinations 3.2 X-ray examination frequency survey methods 3.3 Sources of uncertainty in frequency estimates and how to reduce them 4. Guidance on assessing patient doses 4.1 Patient dose survey methods 4.2 How to convert measured doses into organ and effective doses 4.3 Sources of uncertainty in patient doses and how to reduce them 5. Guidance on assessing age/sex distributions of x-ray patients 6. Guidance on presenting the results of population dose estimates 7. Use of electronic information stored in modern medical imaging equipment and RIS 8. Summary of recommendations 9. References Appendix 1: Detailed descriptions of Top 20 Exams Appendix 2: Typical European age/sex data for x-ray patients Appendix 3: NRPB CT Dose Survey questionnaire Tell us how to do it in the future!

8 EC RP No 154 The x-ray examination definition An x-ray examination or interventional procedure is defined as one or a series of x-ray exposures of one anatomical region/organ/organ system using a single imaging modality (i.e. radiography/ fluoroscopy or CT) needed to answer a specific diagnostic problem or clinical question during one visit to the radiology department, hospital or clinic One type of exam may consist of several subgroups of exams reflecting different clinical indications and various medical practices across the country

9 EC RP N o 154 Frequency survey methods How to categorize examinations Plain film radiography, Radiography/fluoroscopy, CT, Interventional 225 specific exams 70 broader categories the top 20 list How to estimate the number of examinations from a sample of hospitals, clinics or practices from central statistics held by government departments or insurance companies sample scaled up to cover the whole country Identifying uncertainties in frequency estimates Relating codes into actual numbers Insufficiently differentiated codes Bias in the sample and invalid assumptions Lack of frequency data from some important providers of radiology Mistakes in the data recorded or collected

10 Exam type or category % of total frequency* % of total S* Plain film radiography 1. Chest/thorax Cervical spine Thoracic spine Lumbar spine (inc. LSJ) Mammography Abdomen Pelvis & hip Radiography/Fluoroscopy 8. Ba meal Ba enema Ba follow IVU Cardiac angiography All angiography CT 13. CT head CT neck CT chest CT spine CT abdomen CT pelvis CT trunk All CT Interventional 20. PTCA All interventional The Top 20 Exams TOTAL

11 Dose survey methods: the practical dose parameters Radiography and fluoroscopy Mammography CT ESD DAP CTDI w CTDI vol DLP D air MGD For radiography and fluoroscopy the practical dose parameter is the dose area product, DAP for mammography it is the calculated mean glandular dose while for CT it is the weighted and pitch corrected CTDI vol and the dose length product, DLP

12 National average dose figures (NDF) should be established for each of the Top 20 Exams, by collecting information about representative doses from a sample of hospitals and practices in the practical patient dose quantities introduced in Chapter 4.1 in the report The basic data would normally be the same as providing national dose distributions used for establishments of diagnostic reference levels the dose figures are converted to effective dose by means of the conversion coefficients provided in Chapter 4.3. guidance in identifying uncertainties in patient dose estimates is provided in Chapter 4.6 in the report. table 16 concludes it is recommended to collect representative dose figures from >100 rooms.

13 Sample size and matching of conversion coefficients Uncertainties at 95% confidence level Sample size CC Overall >100 rooms ±10% ±10% ±14% Good CC match rooms ±25% ±10% ±27% Good CC match 5-19 rooms ±50% ±10% ±51% Good CC match >100 rooms ±10% ±25% ±27% Poor CC match rooms ±25% ±25% ±35% Poor CC match 5-19 rooms ±50% ±25% ±56% Poor CC match Foreign data only Table 17: Overall uncertainties in mean effective dose estimates as a function of sample size and matching of exposure conditions for conversion coefficients 100 % -50 %

14 Exam type Mean E per examination (msv) Highst Middle Lowest DE CH ALL 10 NL UK 1. Chest/thorax Cervical spine Thoracic spine Lumbar spine Mammography Abdomen Pelvis & hip Ba meal Ba enema Ba follow IVU Cardiac angio All Angiography CT head CT neck CT chest CT spine CT abdomen CT pelvis CT trunk All CT The Top 20 Exams 20. PTCA All Interventional

15 Heads of European Radiation Control Auhtorities, HERCA An initiative from ASN, France Three annual meetings so far Six working groups established to focus specific questions about 1. Dose pass 2. Justification in industrial and medical applications 3. New medical devices and patient release in nuclear medicine 4. Emergency preparedness 5. Stakeholder involvement 6. Surveys on population doses

16 Nordic Radiation protection co-operation X-ray diagnostic group Annual meeting at Hurtigruten 2007 Inspection workshop at SSI 2004 For more than 30 years: WG on matters related to the use of x-ray equipment WG dedicated medical diagnostics and intervention, the so-called Röntgen group" or X-ray diagnostic group. Was first formalized in 1978 and held its first meeting in Norway that year Since 1983 the group has held annual meetings in each of the five Nordic countries on turn

17 Elements in a TOP 20 survey Look into the national system for categorizing or coding radiological examinations, and identify the 20 examination types listed in Table 6 in RP Nº 154 Look in Appendix 1 in the RP Nº154 for detailed examination description for the Top 20 Exams. National average dose figures should be established for each of the Top 20 Exams. Do you have updated average dose figures for all 20 examinations? Based on the dose distributions used to establish local DRL s or other? The dose figures are converted to effective dose by means of the conversion coefficients provided in Chapter 4.3 Discussion of uncertainties and problems in that task based on national efforts

18 Elements in a TOP 20 survey From the secretariat (NRPA, Norway) A project plan in English for participating countries An Excel template to fill in frequency data, dose figures and related uncertainties Information on protected website for the Nordic WG on X-ray diagnostic (Iceland) To be developed nationally (examples) Contact with government departments or insurance companies for collecting central statistics, OR Letter to a representative number of providers of radiological services (hospitals, clinics or practices) An Excel template to fill in frequency data An Excel template to fill in representative dose figures Information about the project in local language motivation! Correspondence by Meeting in the secretariat for drafting the paper

19 Third European IRPA Congress June 2010 Helsinki, Finland Abstract submitted 31. Sept 2009 Deadline for TOP20 data sent to WG6 secretariat 1. March 2010 Secretariat meeting primo March 2010 Draft full paper Draft on circulation in WG6 Full paper deadline 15. April 2010

20 Kartlegging av radiologi i Norge per 2008 Vår 2009 Høst 2009 Vår 2010 Høst 2010 Identifisere TOP 20 i Norge mht utvalg av NORAKO Brev ut 25. juni 2009 m/ prosjektbeskrivelse Excelmaler og FAQ på Nordisk/europeisk samarbeidsprosjekt HERCA WG6 Frister i virksomhetene: 15. September for frekvensdata 15. Oktober for dosedata Prosjektgruppe: Eva G. Friberg Anders Widmark Hilde M. Olerud PURRINGER, Sammenstille TOP20 resultater nasjonalt og internasjonalt Opptelling av alle NORAKO Trender, analyser

21 Kartlegging av radiologi i Norge per 2008 Vi har et detaljert radiologisk kodeverk, NORAKO, som har gjennomgått årlige oppdateringer siden 90 tallet (planlagt skiftet ut fra 2011) Vi er et lite land, og kan henvende oss til samtlige brukere trenger ikke oppskalere studiet Hovedutfordring er at en radiologisk undersøkelse kan kreere flere NORAKO koder. Det kan være vanskelig å holde telling på pasientene CT og MR undersøkelser med flere serier med og uten kontrast Om mammografi telles som ett eller to bryst andre organer/ekstremiteter det er to av telles som en eller to avhengig av koding Andre bidrag til usikkerhet Vi har en utfordring mht å finne alle brukere, spesielt utenfor radiologiske avdelinger (intervensjon, kardiologi, operasjon, kiropraktikk ) For de identifiserte TOP 20 er det lettere, noen få og ganske vel definerte undersøkelser.

22 Norsk radiologisk kodeverk (NORAKO) Norsk radiologisk forening/kith sekretariat Koden av Undersøkelsen/prosedyren består av fem elementer: Modality Location Procedure Side Additional Modality Location Procedure Side Additional C T A B I V Modality Location Procedure Side Additional R G G E S 1. Modalitet: X-rays, US, CT, MRI 2. Lokalisering: Undersøkt organ/anatomisk lokalisering/organ system/region 3. Prosedyre: Spesifiserer undersøkelsen 4. Side: Venstre, høyre, bilateral 5. Tillegg: Tilleggsinformasjon for bruk lokalt Modalitet, lokalisasjon og prosedyredel må fylles ut

23 Eksempler i Norge på identifisering av u.s. og koder Fra RP154 CT head Hode Fra NORAKO hode/hjerne (samlekode), ansiktsregion/orbita, bihuler, sella turcica, tinningben CT KC, KV, AU, FA CT neck Hals Hals (samlecode) CT CM CT chest Thorax Thorax (samlecode) CT TH CT spine Columna Columna: Cervical, Thoracal, Lumbal, Sacrum m/coccyx CT CC, CL CT abdomen Abdomen/Truncus Abdomen (samlecode), Binyrer begge sider, galleblære, galleveier alene, gastrointerstinal tractus, lever inkl. galleveier, lever, pancreas galleveier (samle), milt, nyrer begge sider, pancreas CT AB, HE, RE, PA CT pelvis Bekken/Genitalia Pelvis included genitalia interna (samlecode), Iliosacral joint, prostata, urin blære CT PE, PEAR

24 Kartlegging av radiologi per 2008 i Norge TOP20 frekvens og doser, og alle NORAKO

25 Vedlagt prosjektbeskrivelse

26 Informasjon på nett

27 Klikk Radiologi/rapportering av frekvens/doser Maler for innrapportering av frekvensinformasjon og dosedata kan lastes ned fra linker under. Det vises også til Veileder om representative doser for røntgenundersøkelser [Veileder 5b]. For en mer detaljert informasjon vises det til utsendt brev og prosjektbeskrivelsen. Tilleggsinformasjon Spørsmål og svar om innrapportering av undersøkelsesfrekvens og dose Sist endret: Publisert: forvirrende at NORAKO oppgis i Excel skjema, er det kodene eller undersøkelsene dere vil ha?? hva menes med CT trunk?? hvorfor rapportere på Barium meal, det gjøres jo aldri lenger? hvilke data skal rapporteres for CT urografi?

28 Status from Norway in collecting new dose figures, June 09 No The "TOP 20 list" RP154 NDF Dose Unit #X-ray rooms 1 Chest/Thorax 0.46 Gycm Cervical spine 3 Thoracic spine 4 Lumbar spine (inc.lsj) 6.11 Gycm Mammography 6 Abdomen 4.76 Gycm Pelvis & hip 1.74 Gycm Ba meal 9 Ba enema 8.32 Gycm Ba follow-through 11 IVU 12.3 Gycm Cardiac angiography CT head mgycm CT neck 15 CT chest mgycm CT spine 347 mgycm 21

29 Trends in CT doses Norway NDF preliminary results CT examination DLP mgycm 1995 survey (49 rooms) DLP mgycm 2006 d.d. (# rooms) CT head ,5 (61) CT neck CT chest ,3 (45) CT spine (21) CT abdomen ,3 (49) CT pelvis 576 CT sinuses (3) Chest HR CT (7) CT coronary angiography (4) CT urografi (invest) (4) CT urography (stone) (15) CT colonscopy (3)

30 Forventet utbytte av ny radiologisk kartlegging Utvikling mht totalt antall, bruk av ulike modaliteter (MR, CT, RTG, UL), bruk av nye undersøkelser og prosedyrer Nasjonale variasjoner i adgang til radiologiske tjenester Bruk av CT og betydning for samlet befolkningsdose Sammenligning med andre land i Europa SUM TOP CT Røntgen Dose (msv)