CT Radiation Risks and Dose Reduction
|
|
- Leo Short
- 5 years ago
- Views:
Transcription
1 CT Radiation Risks and Dose Reduction Walter L. Robinson, M.S. D.A.B.S.N.M., D.A.B.M.P., D.A.B.R. Consultant Certified Medical Radiation Health & Diagnostic Imaging Physicist
2 Medical Radiation and Children 1. History 2. Basic dosimetry 3. Biology of radiation effects 4. Unique issues with radiation in children 5. Optimization of risk/benefit ratio 6. Use appropriate techniques 7. Joint efforts with healthcare providers
3 The radiologist must be introduced to the special techniques required to handle infants and children, and must have experience in their use.
4
5
6 Radiology tremendous benefits, but also risks or side effects Side effects were reported within 3 months of discovery
7
8
9 2. Basic dosimetry Dose units Measures of dose Conversions
10 Factors Affecting Patient Dose From C.T. 1. kvp - If mas is constant, increasing kvp will increase dose 2. mas - mas is directly and linearly proportional to dose 3. Slice Width dose can be reduced by increasing slice width; although SNR is improved, axial resolution/detail is reduced 4. Matrix Size and FOV an increase in these results in improved contrast and spatial resolution, at the expense of dose 5. Window and Level a narrower window enhances contrast resolution 6. Radius of Rotation short diameter (mobile CT) provides higher patient dose 7. Bowtie Absorber the use of a bowtie absorber with helical CT reduces dose through filtration of softer X-rays 8. Helical Pitch changing the pitch to a higher number reduces dose 9. Beam Width = # detectors x detector thickness affects; the greater the beam width, the more efficient the collection of X-rays, and lower the dose. 10. Use multi-planar reconstruction. Helical slice thickness can be chosen after acquisition.
11 Applying this Knowledge For instance: acquire 5.0 mm slices with no overlap with a helical pitch of 1.2. Reconstruct 5.0 mm slices with 3.0 mm increments to fill the gaps. This improves noise with some resolution loss. With a lowering of mas to reduce effective dose, this is a helpful tip to improve the quality of the image.
12 Helical or spiral scanning slice pattern
13
14 Many different measures of dose Exit dose in medical imaging: e.g. Dose (or KERMA) area product (DAP) Entrance skin exposure (R) Organ dose (RAD or mgy) Dose equivalent (REM or msv) Effective dose (REM or msv) Dose computed from a phantom (e.g. CTDI, MSAD, DLP, etc.)
15 Radiation Dose: measures for risk assessment Absorbed Dose (Gray Gy) For an individual tissue or organ Difficult to measure; not practical Effective Dose Equivalent (Sievert Sv) Nonuniform exposure to organ or region Expression of risk equivalent to whole body exposure Not Scanner Dose Units (mgy) CTDI vol and DLP: phantom determination Not helpful in assigning risk without conversion!!
16 CTDI CT Dose Index On scanner consoles Based on phantom (16 or 32 cm diameter) Only represents the dose to the phantom based on CT parameters selected Does not indicate dose to the child in the CT scanner Conversions of CTDI to effective dose are only rough estimations for children e.g. no age based chest modifications
17 C.T. Radiation Absorbed Dose Descriptors CTDI - Computed Tomography Dose Index the dose to the central axis point in a single slice CTDI I - (i = # slices) so the CTDI 100 = single slice dose in the center of the body in the center of 100 mm CTDI w - (w = weighted) = 2/3 surface (1 cm.) x 1/3 center CTDI v = CTDI w if pitch is 1.0 = 1.0 RAD. If pitch is 0.9 = 1.1 RAD. If pitch is 1.1 = 0.9 RAD. If the single slice dose is 1.0 RAD, then the center of 14 slices can be 1.5 to 2.0 RAD, from scattered dose from adjacent slice dose contributions.
18 C.T. Dose Descriptors Cont d DLP = Dose Length Product is the bridge from CTDI to Effective Dose. CTDI v x scan length (slice width x # slices) = DLP in mgy-cm Effective Dose Equivalent (EDE) or Effective Dose = the whole body dose equivalent from a dose to a portion of the body EDE = Sum of the weighting factors for various organ or tissues compartments x maximum dose to a given organ or tissue compartment (as of 2007 there are 15 compartments) Bone marrow, breast, colon, lung, and stomach are each 12%; gonads are 8%; bladder, thyroid, liver, and esophagus are 4% each; brain, bone surface, salivary glands, and skin are 1% each, with the remainder 12%.
19 For Instance RADS EDE PA Chest REM C.T. Head REM C.T. Abd REM C.T. Ped. Abd REM Annual Background Radiation 0.3 REM Radiation Risk for Children is 3 times that of the Adult
20 Effective Dose It is a radiation dose quantity It is a computation based on: Organ dose and radiosensitivity Weighting factors
21 Biological Effects of Radiation Learned from the Past: Deterministic effects Stochastic effects
22 There are Two Types of Bio Effects Dose dependent: severity depends on dose there is a threshold burns, hair loss This is a deterministic effect
23
24 Deterministic Effects
25
26
27 There are Two Types of Bio Effects Non dose dependent: severity is independent of dose risk of event occurring is dependent on dose there is no threshold cancer, genetic mutations This is a stochastic effect
28 Biological effects of radiation damage to DNA Reactions are rapid Induction of cancer takes many years The damage to DNA may lead to genomic instability
29 4. Unique issues with radiation in children Plain film history Scoliosis Therapy Tinea capitis Thymus Low dose effect and cancer Atomic bomb survivors Brenner
30 96 minutes of x rays
31 Typical Radiation Doses (msv) Average annual technician dose 3.2 Natural background 3.5 Dental x-rays.09 BE (marrow) 8.75 CXR (marrow).01 Mammogram (breast) Airline passenger.03 Flight crew / attendants 1.6 CT < msv
32 Typical Medical Radiation Doses: 5 year-old (msv*) CXR Equivalents 3-view ankle view chest.02 Tc-99m radionuclide gastric emptying.06 Tc-99m radionuclide cystogram.18 Tc-99m radionuclide bone scan up to 6.2 FDG PET 15.3 Fluoroscopic cystogram <.33 Chest CT up to 3 Abdomen CT up to 5 1/14 th * This is effective dose; organ doses (in mgy) will differ
33 One PET CT in a 5 yr old 23.3 msv 1165 chest x rays, or years of background radiation
34 AJR Feb 2001
35 AJR February 2001
36
37 Fatal Cancer Risk Estimated Debated May be zero May be, in children, 1 in 500-1,000 risk* from a single CT * Risk is of fatal cancer!!
38 Is Low-level Ionizing Radiation Harmful? Support: NCRP ICRP BEIR NCI FDA ACR, AAPM, etc.
39 Brenner et al, 2003* Above doses of msv (protracted exposure) or msv (acute exposure), direct epidemiologic evidence from human populations demonstrate the exposure to ionizing radiation increases the risk of some cancer.
40 Conclusions from BEIR VII (2005) include: the risk of cancer proceeds in a linear fashion at lower doses without a threshold and the smallest dose has the potential to cause a small increase risk to humans.
41 UNSCEAR 2000 It should be noted, however, that the inability to detect increased [cancer] risks at very low doses does not mean that those increases do not exist.
42 Pierce, Preston, Rad Res 151 pg : 2000 Brenner Pediatric Radiology Apr 2002 pg 230
43
44 Sensitivity of children to radiation Digital uncoupling of final product and dose Radiation sensitivity inversely with age Adult risk is 5%/Sv; children is 16%/Sv, or three times higher.
45 Radiation Risks in Children: No Debate Tissues are more radiosensitive Longer lifetime to manifest radiation-induced injury (cancer, cataracts) Each exam (therefore dose) is cumulative depending upon where the dose is delivered
46 Effective Dose Equivalent (EDE) Equal exposure: Child EDE > adult EDE
47 Huda et al Radiology 203: 1997 pg 421
48 Risk vs. Benefits Let us never forget, that a properly prescribed diagnostic test utilizing C.T. for children has its benefits. Benefits that most of the time far exceed the risk. The risk, after all is to the increased possibility of a cancer in years vs. the effective management of the patient s current condition.
49 6. Optimization of benefit/risk ratio Appropriate to do exam Appropriate timing of exam Appropriate modality Get clinician/radiologist together Technologist CT diagnosis should not be delayed due to fear of radiation
50 To improve Benefit/Risk Ratio 1. Prudent patient selection especially children 2. Discussion of non-radiation alternative imaging modalities 3. Review of patient medical radiation history especially abdomen/pelvis, C.T. fluoro, and conventional fluoro 4. Educate and credential referring physicians, E.R. physicians, and radiologists to the relative risks of medical radiation, especially C.T. and Fluoro 5. Develop CT techniques with medical physicist, CT technologist, and Service representatives to develop low dose techniques while optimizing quality. Enlighten CT techs to newer equipment pediatric techniques-built in 6. Strive for ACR and Image Gently recommended published diagnostic radiation levels (DRLs or RRLs)
51 Prudent Patient Selection What is considered prudent? When you feel you can achieve a 95% assureity of a diagnosis that produces the outcome of life over death.
52
53
54 References for Unnecessary High CT Doses Pediatric Radiology : (musculoskeletal) AJR : (chest) AJR : (sinus) AJR : (chest) AJR : (abdomen) AJR : (abdomen) Pediatric Radiology : (brain)
55 How Do We Respond? Pediatrician or E.D. Physicians responsibility: Be sure the test is necessary Use the least invasive modality which gives a high certainty of success Discuss case with radiologist when unsure
56 How Do We Respond? Physician s responsibility: Understand radiation doses of modalities Order on medical indications not parental/legal pressure Discuss options with radiologist Consider information for parents
57
58 How Do We Respond? Radiologists responsibility Understand radiation doses Review requests for higher dose studies Discuss with clinicians Use appropriate technical factors
59
60 Clinical Radiology October 2004; 39:
61 Donnelly et al. AJR. 176;303 Weight Suggested Tube Current (ma) by Weight of Pediatric Patients for Single-Detector Helical CT ma Abdomen Lbs Kg Chest or Pelvis >150 >70 >140 >170
62 Radiologist - Parameters mas Linear to dose (25-60% reduction in pediatric doses is possible for older CT scanners. Newer scanners may have suggested pediatric techniques selectable by the technologist kvp Non linear to dose 20% kv = 30-40% dose MDCT > radiation
63 Lower Dose Pediatric MDCT Large abnormalities, or High contrast regions Lungs Bones CTA Remember: A change of pitch from 1.1 to 0.9 can be compensated by a decrease in mas by ~20%.
64 15 mas
65 8mAs
66 CT Dose Reduction Bone studies: lower ma Initially 100 ma : 1.3 cgy Lowered ma : 0.5 cgy Currently 20 ma : 0.2 5cGy
67 A Word about Fetal Doses ACR s appropriateness criteria for Pelvic Exposures Try or consider the imaging modalities in the following order: Ultrasound, MRI, Non-pelvic radiographs, non-bone nuclear medicine scans, non-pelvic fluoroscopy or CT, radiography of abdomen/pelvis, PET or bone scans, then pelvic fluoroscopy, CT, CT fluoroscopy. For Pelvic CT, Fluoroscopy, or CT Fluoroscopy consider a pregnancy test on potentially gravid females before performing these tests. Have medical physicist project fetal dose if exposure to female is absolutely required.
68 Fetal Dose Continued Doses calculated to be less than 5 RAD represent a 40% increase in the risk rate of a cancer to the child. For example if risk is 1/100,000, then after 5 RAD to the fetus, the risk becomes 1.4/100,000. Doses exceeding 10 RAD may have consequences including mildly diminished mental capacities. Doses exceeding 15 RAD probably should be recommended for genetic and spiritual counseling, as malformations, Down s Syndrome, and more significant risks for cancer could be in the future life of the child. It should also be considered that the child may spontaneously abort. This is a situation for genetic and spiritual counselors, in conjunction with some deep parental emotional considerations. Also, to be considered is that the child probably will be borne healthy.
69 Conclusion We are part of the way there We Need to be Proactive Involve Non-Imagers Control Our Departments Engage Our Community
70
71 Remember.. There is No Ionizing Radiation When You Don t Do the C.T. Exam
72 The ALARA* Concept in Pediatric CT *As Low As Reasonably Achievable
Why is CT Dose of Interest?
Why is CT Dose of Interest? CT usage has increased rapidly in the past decade Compared to other medical imaging CT produces a larger radiation dose. There is direct epidemiological evidence for a an increase
More informationAccounting for Imaging Dose
Accounting for Imaging Dose High Profile Over-exposures Lead to Growing Concern FDA issues warning in October 2009-209 patients exposed to 8 times typical dose for CT brain perfusion scan (3-4 Gy) - Some
More informationDebra Pennington, MD Director of Imaging Dell Children s Medical Center
Debra Pennington, MD Director of Imaging Dell Children s Medical Center 1 Gray (Gy) is 1 J of radiation energy/ 1 kg matter (physical quantity absorbed dose) Diagnostic imaging doses in mgy (.001 Gy)
More informationManaging the imaging dose during Image-guided Radiotherapy. Martin J Murphy PhD Department of Radiation Oncology Virginia Commonwealth University
Managing the imaging dose during Image-guided Radiotherapy Martin J Murphy PhD Department of Radiation Oncology Virginia Commonwealth University Radiographic image guidance has emerged as the new paradigm
More informationDosimetric Consideration in Diagnostic Radiology
Dosimetric Consideration in Diagnostic Radiology Prof. Ng Kwan-Hoong Department of Biomedical Imaging University of Malaya ngkh@um.edu.my Radiation Dosimetry Workshop, 28-29 March 2014 2 Why do we measure
More informationManaging Patient Dose in Computed Tomography (CT)
Managing Patient Dose in Computed Tomography (CT) International Commission on Radiological Protection Information abstracted from ICRP Publication 87 Available at www.icrp.org Task Group: M.M. Rehani,
More informationBackground Radiation in U.S. ~ msv/yr msv/yr ~0.02 ~0.02 msv msv/day /day (~2 m rem/day) mrem/day) NCRP 4
Patient Safety Concerns in Diagnostic Radiology? Lawrence T. Dauer, PhD, CHP Assistant Attending Health Physicist Department of Medical Physics RAMPS/GNYCHPS Spring Symposium April 30, 2010 Benefits?
More informationManaging Patient Dose in Computed Tomography (CT) INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION
Managing Patient Dose in Computed Tomography (CT) International Commission on Radiological Protection Information abstracted from ICRP Publication 87 Available at www.icrp.org Task Group: M.M. Rehani,
More informationRadiation Dose Reduction Strategies in Coronary CT Angiography
Radiation Dose Reduction Strategies in Coronary CT Angiography Noor Diyana Osman, PhD noordiyana@usm.my Contents: Introduction Radiation dosimetry in CT Radiation risk associated with coronary CT angiography
More informationCT Dose Estimation. John M. Boone, Ph.D., FAAPM, FSBI, FACR Professor and Vice Chair of Radiology. University of California Davis Medical Center
CT Dose Estimation John M. Boone, Ph.D., FAAPM, FSBI, FACR Professor and Vice Chair of Radiology 1 University of California Davis Medical Center CT Dose Estimation Introduction The CTDI Family of Metrics
More informationImplementation of the 2012 ACR CT QC Manual in a Community Hospital Setting BRUCE E. HASSELQUIST, PH.D., DABR, DABSNM ASPIRUS WAUSAU HOSPITAL
Implementation of the 2012 ACR CT QC Manual in a Community Hospital Setting BRUCE E. HASSELQUIST, PH.D., DABR, DABSNM ASPIRUS WAUSAU HOSPITAL Conflict of Interest Disclaimer Employee of Aspirus Wausau
More informationMeasurement of organ dose in abdomen-pelvis CT exam as a function of ma, KV and scanner type by Monte Carlo method
Iran. J. Radiat. Res., 2004; 1(4): 187-194 Measurement of organ dose in abdomen-pelvis CT exam as a function of ma, KV and scanner type by Monte Carlo method M.R. Ay 1, M. Shahriari 2, S. Sarkar 3, P.
More informationUtilize radiation safety principles to reduce the amount of radiation used to achieve desired clinical result.
Minimizing Dose Understand the importance and methods of pre-procedure patient assessment including a review of previous radiologic exams, disease processes and anatomical considerations that may increase
More informationRadiation Dose in Pediatric Imaging
Radiation Dose in Pediatric Imaging A Brief History of Radiology Dose: Why Does It Matter? Measuring Exposure and Dose Deterministic Effects Stochastic Effects Common Exams: What is the Risk? Reducing
More informationRadiation Units and Dosimetry 15 August Kalpana M. Kanal, Ph.D., DABR 1
Introduction Radiation Units and Dosimetry Radiation dose quantities are used as indicators of the risk of biologic damage to patients from x-rays and thus a good knowledge of the different dose parameters
More informationRadiation Exposure 1980 to 2006
Radiation Exposure 1980 to 2006 Background 3-6 msv/yr Natural (85% 45%) Radon Cosmic Rays Air travel Living at Altitude Man-made (15% 55%) Medical Imaging** mgy Radiation Therapy cgy Radiation Whole Body
More informationRadiation Safety in the Catheterization Lab
SCAI FALL FELLOWS COURSE - 2015 Radiation Safety in the Catheterization Lab V. Vivian Dimas, MD, FSCAI Associate Professor Pediatrics, Cardiology UT Southwestern Medical Center Dallas TX None Disclosures
More informationRadiation Safety for New Medical Physics Graduate Students
Radiation Safety for New Medical Physics Graduate Students John Vetter, PhD Medical Physics Department UW School of Medicine & Public Health Background and Purpose of This Training This is intended as
More informationTracking Doses in the Pediatric Population
Tracking Doses in the Pediatric Population Frederic H. Fahey DSc Boston Children s Hospital Harvard Medical School frederic.fahey@childrens.harvard.edu Disclosures Sadly, none that pay me any money! SNMMI
More information3/5/2015. Don t Electrocute Me!: Common Misconceptions in Imaging and Radiation Safety (and What to Do About Them)
Don t Electrocute Me!: Common Misconceptions in Imaging and Radiation Safety (and What to Do About Them) Rebecca Milman Marsh, Ph.D. University of Colorado Department of Radiology Who in the Facility Works
More informationDose-equivalent equivalent = absorbed
UCSF General Surgery 2010 Radiation Risks of Diagnostic Radiology in Trauma Robert A. Izenberg, M.D., FACS University of California, San Francisco San Francisco General Hospital Context Increasingly liberal
More informationDoses from pediatric CT examinations in Norway Are pediatric scan protocols developed and in daily use?
Doses from pediatric CT examinations in Norway Are pediatric scan protocols developed and in daily use? Eva Godske Friberg * Norwegian Radiation Protection Authority, P.O. Box, Østerås, Norway Abstract.
More informationCT Dose Reduction in Pediatric Patients
CT Dose Reduction in Pediatric Patients By Kelly Firestine, RT(R)(CT)(M) Executive Summary CT is an incredibly valuable imaging tool, but there are unique concerns with pediatric patients, including the
More informationFetal Dose Calculations and Impact on Patient Care
Fetal Dose Calculations and Impact on Patient Care Matt Hough, MS, DABR, DABMP Florida Hospital Diagnostic Medical Physics and Radiation Safety Resource ACR-SPR Practice Parameter for Imaging Pregnant
More informationManaging Radiation Risk in Pediatric CT Imaging
Managing Radiation Risk in Pediatric CT Imaging Mahadevappa Mahesh, MS, PhD, FAAPM, FACR, FACMP, FSCCT. Professor of Radiology and Cardiology Johns Hopkins University School of Medicine Chief Physicist
More informationSkyscan 1076 in vivo scanning: X-ray dosimetry
Skyscan 1076 in vivo scanning: X-ray dosimetry DOSIMETRY OF HIGH RESOLUTION IN VIVO RODENT MICRO-CT IMAGING WITH THE SKYSCAN 1076 An important distinction is drawn between local tissue absorbed dose in
More informationSTUDIES OF LOW-DOSE RADIATION AND CANCER. E. Lubin
STUDIES OF LOW-DOSE RADIATION AND CANCER E. Lubin 1 RELEVANT DATA BEIR VII 2006 UNSCEAR 2000 ICRP PIERCE D. PRESTON DL Japanese survivors. CARDIS E. IARC occupational exposure. BRENNER D. CT exposure and
More informationToshiba Aquillion 64 CT Scanner. Phantom Center Periphery Center Periphery Center Periphery
Comparison of radiation dose and imaging performance for the standard Varian x-ray tube and the Richardson Healthcare ALTA750 replacement tube for the Toshiba Aquillion CT scanners. by Robert L. Dixon,
More informationPage 1 of 5 Patient Safety: Radiation Dose in X-Ray and CT Exams What are x-rays and what do they do? X-rays are forms of radiant energy, like light or radio waves. Unlike light, x-rays can penetrate the
More informationRadiation Doses in Radiology: Influence of Standards and Regulations
Radiation Doses in Radiology: Influence of Standards and Regulations Beebe Symposium National Academy of Sciences December 9, 2009 Washington D.C. Orhan H Suleiman MS PhD, FAAPM Senior Science Policy Adviser
More informationRadiopharmaceuticals. Radionuclides in NM. Radionuclides NUCLEAR MEDICINE. Modes of radioactive decays DIAGNOSTIC THERAPY CHEMICAL COMPOUND
Univerzita Karlova v Praze - 1. Lékařská fakulta Radiation protection NUCLEAR MEDICINE Involving the application of radioactive substances in the diagnosis and treatment of disease. Nuclear medicine study
More informationIntroduction and Background
CT Lung Cancer Screening and the Medical Physicist: Background, Findings and Participant Dosimetry Summary of the National Lung Screening Trial (NLST) Randell Kruger, PhD, DABR Medical Physics Section
More informationRadiation Dosimetry for CT Protocols
Radiation Dosimetry for CT Protocols This document contains radiation dosimetry information from CT scans and can be used by investigators to estimate the dosimetry information required by the JRSC or
More informationESTABLISHING DRLs in PEDIATRIC CT. Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine
ESTABLISHING DRLs in PEDIATRIC CT Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine CT Dose Indices CTDI INTRODUCTION CTDI 100, CTDI w, CTDI vol
More informationRADIATION SAFETY. Junior Radiology Course
RADIATION SAFETY Junior Radiology Course Expectations for the Junior Radiology Course Medical School wants students to learn basic principles, factual knowledge, safety info, etc. Medical Students want
More informationRadiation related cancer risk & benefit/risk assessment for screening procedures
WHO Workshop on Justification of CT for IHA 15-17 Oct 2014 Radiation related cancer risk & benefit/risk assessment for screening procedures Elke A. Nekolla BfS Federal Office for Radiation Protection Radiation
More informationCalculation of Effective Doses for Radiotherapy Cone-Beam CT and Nuclear Medicine Hawkeye CT Laura Sawyer
Calculation of Effective Doses for Radiotherapy Cone-Beam CT and Nuclear Medicine Hawkeye CT Laura Sawyer Department of Medical Physics and Bioengineering, Royal United Hospital, Bath Overview Varian Acuity
More informationComputed tomography Acceptance testing and dose measurements
Computed tomography Acceptance testing and dose measurements Jonas Andersson Medical Physicist, Ph.D. Department of Radiation Sciences University Hospital of Norrland, Umeå Sweden Contents The Computed
More informationAssessment of effective dose in paediatric CT examinations
Assessment of effective dose in paediatric CT examinations E. Dougeni 1,2 CL. Chapple 1, J. Willis 1, G. Panayiotakis 2 1 Regional Medical Physics Department, Freeman Hospital, Freeman Road, Newcastle
More informationChief Radiographer TEI Clinical Associate 2016
MDCT Principles i and Applications Ε ΑGADAKOS MSc Ε. ΑGADAKOS MSc Chief Radiographer TEI Clinical Associate 2016 Aim To understand d recent technological advances in MSCT and how they can be effectively
More informationEFFECTIVE DOSE ESTIMATION AND CANCER RISK ASSESSMENT DUE TO SOME SELECTED CT EXAMINATIONS AT SWEDEN GHANA MEDICAL CENTRE (SGMC)
EFFECTIVE DOSE ESTIMATION AND CANCER RISK ASSESSMENT DUE TO SOME SELECTED CT EXAMINATIONS AT SWEDEN GHANA MEDICAL CENTRE (SGMC) BY KOFI OKYERE AKYEA-LARBI 10442894 THIS THESIS IS SUBMITTED TO THE MEDICAL
More informationEstimating Risks from CT Scans - in the Context of CT Scan Benefits
Estimating Risks from CT Scans - in the Context of CT Scan Benefits David J. Brenner Center for Radiological Research Columbia University Medical Center djb3@cumc.columbia.edu There is no question that
More information8/18/2011. Acknowledgements. Managing Pediatric CT Patient Doses INTRODUCTION
Managing Pediatric CT Patient Doses Keith J. Strauss, MSc, FAAPM, FACR President X-Ray Computations, Inc. Boston, Massachusetts Acknowledgements Marilyn Goske, MD John Boone, PhD Cynthia McCollough, PhD
More informationProf. Dr. Doğan BOR Ankara University Institute of Nuclear Science
PATIENT DOSIMETRY IN DIAGNOSTIC RADIOLOGY MODALITIES Prof. Dr. Doğan BOR Ankara University Institute of Nuclear Science Ankara University Institute of Nuclear Science USE OF RADIATION! INCREASING? Natural
More informationEstimating Patient Radiation Dose from Computed Tomography
Estimating Patient Radiation Dose from Computed Tomography C. Cagnon, J. DeMarco, E. Angel, M. McNitt-Gray UCLA David Geffen School of Medicine 1 Patient Dose from CT Advances in Technology... Helical
More informationFDG-18 PET/CT - radiation dose and dose-reduction strategy
FDG-18 PET/CT - radiation dose and dose-reduction strategy Poster No.: C-1856 Congress: ECR 2014 Type: Authors: Keywords: DOI: Scientific Exhibit P. Nicholson, S. McSweeney, K. O'Regan; Cork/IE Radiation
More informationCT Optimisation for Paediatric SPECT/CT Examinations. Sarah Bell
CT Optimisation for Paediatric SPECT/CT Examinations Sarah Bell Sarah.bell14@nhs.net Outline 1. Introduction 2. Aims and Objectives 3. Methods 4. Results 5. Discussion 6. Conclusions 7. References Introduction
More informationRadiation Dose Risk and Diagnostic Benefit in Imaging Investigations
American Journal of Bioscience and Bioengineering 2015; 3(3-1): 22-26 Published online April 10, 2015 (http://www.sciencepublishinggroup.com/j/bio) doi: 10.11648/j.bio.s.2015030301.14 ISSN: 2328-5885 (Print);
More informationWhy radiation protection matters?
Why radiation protection matters? Elias Brountzos Professor of Radiology 2 nd Department of Radiology Medical School, University of Athens Athens, Greece A definition for radiation protection Radiation
More informationDose Estimates for Nuclear Medicine Procedures: What are they? Where do they come from?
Dose Estimates for Nuclear Medicine Procedures: What are they? Where do they come from? SNM Continuing Education Lecture Salt Lake City, UT -- June 6, 2010 Darrell R. Fisher Pacific Northwest National
More information3 rd International Symposium on the System of Radiological Protection Seoul, October John Harrison
3 rd International Symposium on the System of Radiological Protection Seoul, October 2015 John Harrison UK Task Group 79 : Use of Effective Dose as a Risk-related Radiological Protection Quantity John
More informationEstimates of Risks LONG-TERM LOW DOSE EFFECTS OF IONIZING RADIATION
Estimates of Risks LONG-TERM LOW DOSE EFFECTS OF IONIZING RADIATION Low Level Radiation Exposure Single exposure of 10 rad or less Larger exposures delivered over periods of days or longer (low dose
More informationJustification, Optimization and Communication in Pediatric CT Imaging: Recent Improvements and Persistent Challenges Designated Emphasis in Nuclear
Justification, Optimization and Communication in Pediatric CT Imaging: Recent Improvements and Persistent Challenges Designated Emphasis in Nuclear Sciences 2016 Seminar Jerrold Bushberg Ph.D., DABMP,
More informationUnderstanding radiation-induced cancer risks at radiological doses
Understanding radiation-induced cancer risks at radiological doses David J. Brenner Center for Radiological Research Columbia University Medical Center New York, NY djb3@columbia.edu Let s distinguish
More informationALTERNATIVES TO THE EFFECTIVE DOSE FOR STOCHASTIC RISK ASSESSMENT IN MEDICAL IMAGING
ALTERNATIVES TO THE EFFECTIVE DOSE FOR STOCHASTIC RISK ASSESSMENT IN MEDICAL IMAGING By ANDRES F. ABADIA A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF
More informationTable of Contents. Introduction 3. Background 4
Training manual Table of Contents Introduction 3 Background 4 What are X-rays? 4 How are X-rays Generated? 5 Primary and Scatter Radiation 6 Interactions with Matter 6 Biological Effects of Radiation 7
More informationSPECIFIC PRINCIPLES FOR DOSE REDUCTION IN HEAD CT IMAGING. Rajiv Gupta, MD, PhD Neuroradiology, Massachusetts General Hospital Harvard Medical School
SPECIFIC PRINCIPLES FOR DOSE REDUCTION IN HEAD CT IMAGING Rajiv Gupta, MD, PhD Neuroradiology, Massachusetts General Hospital Harvard Medical School OUTLINE 1 st Presentation: Dose optimization strategies
More informationCancer Risks from CT Scans: Now We Have Data What Next?
Cancer Risks from CT Scans: Now We Have Data What Next? David J. Brenner, PhD, DSc Center for Radiological Research Columbia University Medical Center djb3@columbia.edu There is no question that CT has
More informationAAPM Annual Meeting. ACR Accreditation Update in CT
AAPM Annual Meeting ACR Accreditation Updates in CT, Ultrasound, Mammography and MRI: ACR Accreditation Update in CT Michael McNitt-Gray, PhD, DABR, FAAPM Professor, Department of Radiological Sciences
More informationRadiation Safety in the Modern Radiology Department: A Growing Concern
ISPUB.COM The Internet Journal of Radiology Volume 5 Number 2 Radiation Safety in the Modern Radiology Department: A Growing Concern G Marshall, S Keene Citation G Marshall, S Keene. Radiation Safety in
More informationCURRENT CT DOSE METRICS: MAKING CTDI SIZE-SPECIFIC
CURRENT CT DOSE METRICS: MAKING CTDI SIZE-SPECIFIC Keith Strauss, MSc, FAAPM, FACR Cincinnati Children s Hospital University of Cincinnati College of Medicine Acknowledgments John Boone, PhD Michael McNitt-Grey,
More informationModule Rhodes
Module 6 10-526-197 Rhodes Health Physicist Concerned with providing occupation radiation protection and minimizing radiation dose to the public. Diagnostic Imaging has changed our world Live longer Work
More informationA more accurate method to estimate patient dose during body CT examinations with tube current modulation
A more accurate method to estimate patient dose during body CT examinations with tube current modulation Poster No.: C-0738 Congress: ECR 2014 Type: Scientific Exhibit Authors: A. Kawaguchi 1, Y. Matsunaga
More informationIonizing Radiation Exposure from Radiologic Imaging: The Issue and What Can We Do?
Ionizing Radiation Exposure from Radiologic Imaging: The Issue and What Can We Do? Background, The increased use of diagnostic imaging requiring the use of ionizing radiation, the rapidly expanding use
More information"The Good Side of Radiation: Medical Applications"
"The Good Side of Radiation: Medical Applications" J. Battista, Ph.D. Medical Physicist London Regional Cancer Program LHSC http://www.macmillan.org.uk/images/cancerinfo Role of Medical Physicists Diagnostic
More informationSteven Aaron Ross, M.D. Pediatric Radiologist El Paso Imaging Consultants El Paso Children s Hospital
Steven Aaron Ross, M.D. Pediatric Radiologist El Paso Imaging Consultants El Paso Children s Hospital I will prescribe regimens for the good of my patients according to my ability and my judgment and never
More informationRadiologic Units: What You Need to Know
Radiologic Units: What You Need to Know TODD VAN AUKEN M.ED. RT (R)(MR) Agenda Greys, Sieverts, Coulombs per kg, & Becquerel's Conventional Units Other Concepts (LET, Q-Factor, Effective Dose, NCRP Report
More informationAssessment of radiation risk to pediatric patients undergoing conventional X-ray examinations
Radioprotection 50(1), 19-25 (2015) c EDP Sciences 2015 DOI: 10.1051/radiopro/2014023 Available online at: www.radioprotection.org Article Assessment of radiation risk to pediatric patients undergoing
More informationPNRA-RG (Rev. 0) December, 2017 PROTECTION OF PATIENTS IN DIAGNOSTIC RADIOLOGY REGULATORY GUIDE PAKISTAN NUCLEAR REGULATORY AUTHORITY
PNRA-RG-904.05 (Rev. 0) December, 2017 PROTECTION OF PATIENTS IN DIAGNOSTIC RADIOLOGY REGULATORY GUIDE PAKISTAN NUCLEAR REGULATORY AUTHORITY For Further Details Directorate of Policies & Procedures PAKISTAN
More informationRadiology Rounds A Newsletter for Referring Physicians Massachusetts General Hospital Department of Radiology
Radiology Rounds A Newsletter for Referring Physicians Massachusetts General Hospital Department of Radiology Minimizing CT Radiation Dose CT examinations improve health care and are an essential part
More informationOutline. NCRP Scientific Committee 6-2
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
More informationX-Ray & CT Physics / Clinical CT
Computed Tomography-Basic Principles and Good Practice X-Ray & CT Physics / Clinical CT INSTRUCTORS: Dane Franklin, MBA, RT (R) (CT) Office hours will be Tuesdays from 5pm to 6pm CLASSROOM: TIME: REQUIRED
More informationcreated by high-voltage devices Examples include medical and dental x-rays, light, microwaves and nuclear energy
What is radiation? Radiation is energy emitted from a source, that travels through space and can penetrate matter. Listed below are two types that we are exposed to and contribute to our overall radiation
More informationCT Dosimetry in the Clinical Environment: Methods and Analysis
CT Dosimetry in the Clinical Environment: Methods and Analysis Manuel Arreola, Ph.D. DABR Associate Chair of Radiology Director, Medical Physics Graduate Program Department of Radiology University of Florida
More informationPeople Exposed to More Radiation from Medical Exams
People Exposed to More Radiation from Medical Exams With its release of a new report, titled Ionizing Radiation Exposure of the Population of the United States (Report No. 160, 2009), the National Council
More informationQuiz True/False: Large amounts of radiation to insects will cause them to mutate!
RADS, REMS & ROENTGENS Jack L. Barr, M.S., R.T.R., F.A.S.R.T. Quiz True/False: Large amounts of radiation to insects will cause them to mutate! LARGE AMOUNTS OF RADIATION WILL CAUSE VEGETABLES TO BECOME
More informationRecent Progress in Radiation Dosimetry for Epidemiology and Radiological Protection. John Harrison ICRP Committee 2
Recent Progress in Radiation Dosimetry for Epidemiology and Radiological Protection John Harrison ICRP Committee 2 Joint ICRP-RERF-JHPS Workshop: Tokyo, December 2017 Task Group 79 : Use of Effective Dose
More informationAsk EuroSafe Imaging Tips & Tricks. CT Working Group. On the use of Diagnostic Reference Levels in CT
Ask EuroSafe Imaging Tips & Tricks CT Working Group On the use of Diagnostic Reference Levels in CT Robert Bujila (Karolinska University Hospital, SE) Eileen Kelly (Galway University Hospitals, IE) Matthias
More informationRAMPS-GNYCHPS 2010 Spring Symposium New York, NY, April 30, Error Prevention and Patient Safety for Radiation Treatment and Diagnosis
RAMPS-GNYCHPS 2010 Spring Symposium New York, NY, April 30, 2010 Error Prevention and Patient Safety for Radiation Treatment and Diagnosis Radiotherapy and Radiology in the 21 st Century: Risks and Benefits
More informationCT Head Dose Reduction Using Spiral Scanning Protocol
CT Head Dose Reduction Using Spiral Scanning Protocol Reed, William J MD; Broderick, Daniel F, MD; Weindling, Steven M, MD; Czervionke, Leo F MD; and Morin, Richard L; PhD; Mayo Clinic, Department of Radiology;
More informationPHY138Y Nuclear and Radiation
PHY38Y Nuclear and Radiation Professor Tony Key MP40 key@physics.utoronto.ca Announcements MP problems set #4 due Sunday at midnight PS#5 WRITTEN now posted! - do in teams, no Lone Wolves!! NB correction
More informationErnest Rutherford:
November 1895: Roentgen discovers x rays February 1896: Becquerel discovers radioactivity Ernest Rutherford 1898-99 Ernest Rutherford: 1898-99 The Electromagnetic Spectrum Interaction of Charged Particles
More informationEstimating Risk of Low Radiation Doses (from AAPM 2013) María Marteinsdóttir Nordic Trauma,
Estimating Risk of Low Radiation Doses (from AAPM 2013) María Marteinsdóttir Nordic Trauma, 20140521 Stochastic effects Linear No Threshold - LNT-model Uncertain Material produced by William R. Hendee
More informationTHE UNIVERSITY OF OKLAHOMA HEALTH SCIENCES CENTER GRADUATE COLLEGE RADIATION DOSE ESTIMATION FOR DIAGNOSTIC MODALITIES
THE UNIVERSITY OF OKLAHOMA HEALTH SCIENCES CENTER GRADUATE COLLEGE RADIATION DOSE ESTIMATION FOR DIAGNOSTIC MODALITIES A THESIS SUBMITTED TO THE GRADUATE FACULTY in partial fulfillment of the requirements
More informationManaging the imaging dose during image-guided radiation therapy
Managing the imaging dose during image-guided radiation therapy Martin J Murphy PhD Department of Radiation Oncology Virginia Commonwealth University Richmond VA Imaging during radiotherapy Radiographic
More informationAcknowledgments. A Specific Diagnostic Task: Lung Nodule Detection. A Specific Diagnostic Task: Chest CT Protocols. Chest CT Protocols
Personalization of Pediatric Imaging in Terms of Needed Indication-Based Quality Per Dose Acknowledgments Duke University Medical Center Ehsan Samei, PhD Donald Frush, MD Xiang Li PhD DABR Cleveland Clinic
More informationIMAGE GENTLY HOW CAN YOU HELP?
IMAGE GENTLY HOW CAN YOU HELP? Keith J. Strauss, MSc, FAAPM, FACR Director, Radiology Physics & Engineering Children s s Hospital Boston Harvard Medical School Acknowledgment Marilyn J. Goske,, MD Robert
More informationPrepublication Requirements
Issued Prepublication Requirements Standards Revisions for Organizations Providing Fluoroscopy Services The Joint Commission has approved the following revisions for prepublication. While revised requirements
More informationCone Beam CT Protocol Optimisation for Prostate Imaging with the Varian Radiotherapy OBI imaging system. Dr Craig Moore & Dr Tim Wood
Cone Beam CT Protocol Optimisation for Prostate Imaging with the Varian Radiotherapy OBI imaging system Dr Craig Moore & Dr Tim Wood Background With the increasing use of CBCT imaging alongside complex
More informationEstimated Radiation Dose Associated With Low-Dose Chest CT of Average-Size Participants in the National Lung Screening Trial
Medical Physics and Informatics Original Research Larke et al. Estimated Radiation Dose for Low-Dose Chest CT Medical Physics and Informatics Original Research Frederick J. Larke 1 Randell L. Kruger 2
More informationRadiologist Update on the Relative Patient Doses Associated with Diagnostic Imaging Modalities Today
Radiologist Update on the Relative Patient Doses Associated with Diagnostic Imaging Modalities Today Introduction The purpose of this presentation is to inform the busy practicing radiologist as to the
More informationIonizing Radiation Exposure from Radiologic Imaging
Ionizing Radiation Exposure from Radiologic Imaging Background The increased use of diagnostic imaging requiring the use of ionizing radiation, the rapidly expanding use of computed tomography in the emergency
More informationLow Dose CT Lung Screening: What is Technically Required?
Low Dose CT Lung Screening: What is Technically Required? COMP/CCPM Annual Scientific Meeting Ottawa, Ontario July 15 th, 2017 Yogesh Thakur, PhD, MCCPM Medical Physicist Lead and Regional RSO (X-Ray)
More informationOutline. Lifetime Attributable Risk 10 mgy in 100,000 exposed persons (BEIR VII 2006) SPECT/CT and PET/CT Dosimetry
SPECT/CT and PET/CT Dosimetry Lifetime Attributable Risk 10 mgy in 100,000 exposed persons (BEIR VII 2006) All Solid Tumors Leukemia Frederic H. Fahey DSc Male Female Male Female Children s Hospital Boston
More informationPreparing for Medical Physics Components of the ABR Core Examination
Preparing for Medical Physics Components of the ABR Core Examination The ABR core examination for radiologists contains material on medical physics. This content is based on the medical physics that is
More informationDETERMINATION OF ENTRANCE SKIN DOSE FROM DIAGNOSTIC X-RAY OF HUMAN CHEST AT FEDERAL MEDICAL CENTRE KEFFI, NIGERIA
DETERMINATION OF ENTRANCE SKIN DOSE FROM DIAGNOSTIC X-RAY OF HUMAN CHEST AT FEDERAL MEDICAL CENTRE KEFFI, NIGERIA Full Length Research Article 1 Ibrahim, U, 3 Daniel, I.H., 3 Ayaninola, O., 4 Ibrahim,
More informationRadiation Safety For Anesthesiologists. R2 Pinyada Pisutchareonpong R2 Nawaporn Sateantantikul Supervised by Aj Chaowanan Khamtuicrua
Radiation Safety For Anesthesiologists R2 Pinyada Pisutchareonpong R2 Nawaporn Sateantantikul Supervised by Aj Chaowanan Khamtuicrua Modern World Non Ionizing VS Ionizing Non Ionizing Harmless Ex. visible
More informationRadiation Dose Specification
Chapter 9 Dose Limits for Exposure to Ionizing Radiation Dose Limits for exposure to Ionizing Radiation apply to: Occupational workers Nonoccupational workers Radiation Dose Specification Equivalent Dose
More informationABSTRACT. Objectives: To investigate the radiation dose received by patients undergoing routine plain x-ray
Radiation Dose Distribution for Patients Undergoing Routine Radiological Scans for Kidney Stone Diagnosis at the University Hospital of the West Indies DC Walker 1, WD Aiken 2, S Shah 3, MK Voutchkov 1,
More informationICRP Recommendations Evolution or Revolution? John R Cooper Main Commission
ICRP Recommendations Evolution or Revolution? John R Cooper Main Commission 3 September 2009 ICRP Recommendations 1. Reasons for new Recommendations 2. Summary of health risks 3. Summary of changes to
More information