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AAPM-Ncrptalk July08v2 Magnitude of Medical Radiation Exposures to US population Mahadevappa Mahesh, MS, PhD, FAAPM. Assistant Professor of Radiology & Cardiology Chief Physicist - Johns Hopkins Hospital The Russell H. Morgan Department of Radiology and Radiological Science Johns Hopkins University, Baltimore, MD AAPM Annual Meeting, Houston, TX 2008 Outline NCRP SC 6-2: Purpose • To update NCRP Report 93 published in 1987 • Purpose and Goals of NCRP SC 6-2 • Evaluate total effective dose equivalent to members • Data Sources & Results* of U.S. public exposed annually from • How should regulatory agencies − Medical sources react? − Radon • Discussions & Conclusions − Cosmic and Terrestrial Radiation − Consumer Products and − Other Radiation Sources (occupational, nuclear fuel cycle, radioactive fallout and miscellaneous sources) NCRP Scientific Committee 6-2 NCRP SC 6-2: Radiation Exposure of U.S. population • Kenneth R. Kase - Chairman • Subcommittees: − Industrial Exposures • Dennis M. Quinn - Chairman − Occupational exposures • Kenneth L. Miller - Chairman Medical Published in Occupational − Medical Patient Exposures 1987 • Bruce Thomadsen - Chairman − Natural Background Radiation • Daniel J. Strom - Chairman − Consumer Products and Miscellaneous Sources • Orhan H. Suleiman - Chairman Natural Technologically enhanced New report expected to be published in 2008 © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD NCRP Report 93*: 1987 1989 Annual effective dose equivalent to US population circa 1980-82 Purpose Natural 82% • Natural Sources 3.0 mSv Man-made 18% • To update NCRP Report 93 published in 1987 − Radon 2.0 mSv − Other 1.0 mSv and NCRP report 100 published in 1989 • Man-made Sources 0.6 mSv − Occupational, Consumer • Last major medical data used in NCRP Report products, nuclear fuel cycle and other miscellaneous No. 93 are from 1982 or earlier products 0.07 mSv • Evaluate the current total effective dose to − Medical 0.53 mSv • X-rays 0.39 mSv members of U.S. public exposed annually from • Nuclear Medicine 0.14 mSv Medical Radiation Exposures * Published in 1987 NCRP SC 6-2: Medical Subgroup Members Goals Chairperson: B. Thomadsen,University of Wisconsin • Estimate current radiation exposure to US population • M. Bhargavan American College of Radiology − Number and types of medical procedures • D. Gilley State of Florida − Effective radiation dose per procedure • J. Gray DIQUAD, LLC • Examine past and future trends of medical exposures • J. Lipoti State of New Jersey • Modalities • M. Mahesh Johns Hopkins University • J. McCrohan US FDA − Radiography, Fluoroscopy, Mammography, Dental • F. Mettler Univ of New Mexico VA − Interventional • T. Yoshizumi Duke University − CT • M. Rosenstein Scientific NCRP Consultant − Nuclear Medicine • K. Kase Stanford SC 6-2 Chair − Radiation Therapy Methods Assumptions • Benefit exceeds risk: Issue not examined in this • Collective doses estimated independently for each report modality • Data sources: • Modality groups: − Multiple data sets − CT, Nuclear medicine, Radiography & Fluoroscopy, Mammography, Interventional, Dental, Chiropractic − Incomplete data sets required assumptions and cross Radiology, Bone Densitometry, and Radiation Therapy checking between data sets • Procedures within each modality categorized by • Weighting Factors: Used ICRP 60 (1990). Past body part or organ system reports used older ICRP 26 (1977) and new factors are suggested © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Modalities & procedures considered in the report Major and minor data sources • Computed Tomography (CT) • Commercial (IMV Benchmark) • Nuclear Medicine Procedures • Medicare payment data (2003-2005) • Radiography and Fluoroscopy • VA Health Care System • Interventional Radiography • Claims data from large national employer plan • US FDA • Mammography • CRCPD • Dental and Chiropractic • State radiation programs • Bone Densitometry • Large hospitals • American College of Radiology • Radiation Therapy • Literature IMV Benchmark Reports Medicare Payment Data • Based on responses from hospitals and estimated • Claims data for Medicare fee-for-service enrollees to identified universe of US hospitals (~7000) • Summarized procedure counts for each modality and • Surveys had high response rates (~60%) sorted by Common Procedure Coding System (HCPCS) • Reports used: CT, nuclear medicine, cardiac Common Procedural Terminology (CPT) code catheterization, radiography-fluoroscopy, • 100% medical claims from 1997-2004 angiography, mammography, PET and radiation • Accounts for nearly 40 million enrollees therapy • Mainly covers persons >65 years old and disabled • Reports between 2003-2006 • Represents one-third of all utilization and one-seventh of • Data includes all ages US population Veterans Administration (VA) Large National Employer Program (LNEP) • Procedure counts available for 1991-2006 • Claims data available for 2003 Grouped by HCPCS-CPT, patient age and • • Data summarized by modality and body part gender • Summarized data for 2003-2006 used for • 4 millions nationally distributed comparisons • All ages and gender included • 4 to 7 million enrollees, mostly male • Data used for spot-check distributions of • Women and children under-represented procedures for certain modalities © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Data: Reconciliations and Limitations Results • Procedure counts and distribution from IMV reports • Distribution of procedure counts across body part or organ system was matched with data from other data sources • Limited data available on volumes of chiropractic and dental imaging Computed Tomography (CT) • Annual growth over 1993-2006: − CT Procedures > 10% vs US population < 1% • Nearly 67 million CT procedures in US in 2006 Computed Tomography • Data correlated to nearly 7649 hospitals in US • Pediatric CT ~ 8-10% of total procedures Categories of CT procedures Number of CT procedures in US (62.0 million in 2006) HCAP: ~80% of all CT procedures IMV Benchmark Report on CT, 2006 IMV 2006 © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Distribution Pattern of CT Scanners in US* CT scans of Abdomen and Pelvis Exam distribution vs US Population* ~ 20% of population >55 years, receives >55% of CT scans IMV 2006 * LNEP 2003 Preliminary Results for CT (2006) CT: Procedures vs Collective Dose Number % Collective dose % (millions) Person Sv Head 19.0 28 38,000 8.7 Chest 10.6 16 74,000 17.0 84% Abd/Pelvis 25.4 38 254,000 58.0 Extremity 3.5 5 500 0.1 CT Angiogram 4.3 6 56,000 12.8 Miscellaneous 4.2 6 15,000 3.4 Collective dose ~438,000 person Sv TOTAL 67 438,000 Effective dose per person from CT ~1.46 mSv Preliminary results not yet reviewed and approved by NCRP Council Preliminary results not yet reviewed and approved by NCRP Council Radiation dose from CT: Then (1980) and Now (2006) • According to NCRP report 100 − Collective dose for CT 3,700 person Sv • According to current estimations − Collective dose for CT 440,000 person Sv − Effective dose per capita ~1.5 mSv and some radiation exposure © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Nuclear Medicine • Annual growth over 1993-2005: − Nuclear Medicine Procedures > 5% vs US population < 1% • Nearly 17 million nuclear medicine procedures in US Nuclear Medicine in 2005 • Data correlated to nearly 7200 hospitals in US • Largest increases in cardiac procedures − 1% in 1973 to 57% in 2005 Number of nuclear medicine procedures in US Type of Nuclear Medicine Procedures IMV Benchmark Report on NM, 2005 IMV 2005 Nuclear Medicine: Procedures vs Collective Dose Preliminary Results for Nuclear Medicine (2005) Procedures by categories (%) Collective dose by categories (%) Number Collective dose % % millions Person Sv Brain <0.1 <2 260 0.1 Thyroid < 0.1 <2 400 0.2 Lung 0.74 4 2,000 0.9 Cardiac 9.80 57 188,000 85.2 GI 1.21 7 3,500 1.6 Renal 0.47 3 650 0.3 Bone 3.45 20 20,500 9.3 Infection 0.38 2 1,300 0.6 Collective dose ~231,000 person Sv Tumor 0.34 2 3,900 1.8 Effective dose per person ~0.80 mSv Total 17.2 220,500 Preliminary results not yet reviewed and approved by NCRP Council © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Radiation doses from Nuclear Medicine: Then (1980) and Now (2006) • According to NCRP report 100 − Collective dose for Nuclear Medicine 32,000 person Sv • According to current estimations Radiography & Fluoroscopy − Collective dose for Nuclear Medicine 231,000 person Sv − Effective dose per capita ~0.80 mSv Radiography & Fluoroscopy Radiography: Procedures vs Collective Dose Procedures by categories (%) Collective dose by categories (%) • Data includes mammography, dental, chiropractic radiographic procedures, bone densitometry & certain fluoroscopy procedures • Limited data available for dental and chiropractic procedures Collective dose ~98,000 person Sv Effective dose per person from Radiography ~0.30 mSv Preliminary results not yet reviewed and approved by NCRP Council Radiation dose from conventional radiography and fluoroscopy: Then (1980) and Now (2006) • According to NCRP report 100 − Collective dose 71,000 person Sv • According to current estimations Interventional − Collective dose 98,000 person Sv − Effective dose per capita ~0.32 mSv © Mahadevappa Mahesh, MS, PhD, FAAPM. [email protected] Johns Hopkins University, Baltimore, MD Interventional
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