1. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
What can radiation do? L03

2. Answer True or False
It is accepted that the carcinogenic effects of radiation have a threshold.
For deterministic effects of radiation, the severity increases with dose.
Radiation risk in children is 2-3 times lower than people above 45 years.
Skin injuries and lens opacities are deterministic effects of radiation.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

3. Educational Objectives
Different radiation effects
Their probability in fluoroscopy practice
Special concerns in children, young & pregnant females
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

4. What can radiation do?
When used appropriately it can benefit an individual by aiding in the diagnosis of disease at an early stage where treatment may be more effective than if detected late.
In case of inappropriate use it also has a potential to harm an individual by placing them at increased risk of radiation-induced cancer later in life.
Benefit and Risk must be carefully balanced when X ray imaging is undertaken
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

5. Cancer Genetic effects Skin injuries Cataract Infertility Death
What can radiation do?
Cancer
Genetic effects
Skin injuries
Cataract
Infertility
Death
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

6. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

7. Deterministic Effects (predictable and preventable)
Cataract formation
Skin injury
Impaired fertility
Threshold
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

8. Stochastic and Deterministic Effects
A stochastic effect is one where the severity of radiation damage is not related to the dose and the probability of occurrence increases with increasing radiation dose, e.g., development of cancer. There is no threshold for stochastic effects.
A deterministic effect is one where the severity depends upon the radiation dose, e.g., skin burns. There is a threshold for deterministic effects.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

9. This requires discussion on how radiation effects occur
Physician
You mean I can get cancer even if I am working with small amount of radiation?
This requires discussion on how radiation effects occur
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

10. Is there RADIATION in this room?
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

11. Radiation from Natural Sources
Normally 1-3 mSv/year
In areas of high background, 3-13 mSv/year
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

12. Relative Dose Ranges in Medical Imaging
High dose fluoroscopy CT
Radiography
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

13. Effects of Radiation on Cells
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

14. Chromosomes
Nucleus Double membrane surrounding the chromosomes and the nucleolus. Pores allow specific communication with the cytoplasm. The nucleolus is a site for synthesis of RNA making up the ribosome.

15. Direct Effect
Incoming photon strikes the DNA molecule and damages it; either a base pair is damaged or a support strand is damaged.
Damage from direct effect is rare; possibly as low as 1%.

16. Indirect effect Incoming photon interacts with a water molecule
The ionizing radiation breaks chemical bonds in the water molecule
The water molecule fragments form highly reactive chemicals such as hydrogen peroxide and other free radicals
These highly reactive chemicals attack the DNA molecule damaging its chemical bonds

17. Induction of DNA changes
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

18. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

19. radiation hits a cell nucleus!
No change
DNA mutation
radiation hits a cell nucleus!
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

20. Cell survives but mutated
Viable Cell
Mutation repaired
Unviable Cell
Cell death
Stoch.eff.
DNA Mutation
p  a D
Cell survives but mutated
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

21. Deterministic effects caused by cell death: burns, organ failure, death
At 3 wks
At 6.5 mos
Surgical flap
Following ablation procedure with arm in beam near port and separator cone removed. About 20 minutes of fluoroscopy.
Reproduced from Wagner – Archer, Minimizing Risks from Fluoroscopic X Rays, 3rd ed, Houston, TX, R. M. Partnership, 2000
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

22. Altered process due to mutated genes
Normal process
Altered process due to mutated genes
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

23. Altered process due to mutated genes
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

24. Effects in the embryo/foetus
Stochastic effects
Carcinogenesis
Hereditary effects
Effects in the embryo/foetus
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

25. Carcinogenesis

26. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

27. So now that you have scared me with this information, what should I do?
It is not our intent to scare you with these facts, but to educate about potential long-term risks.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

28. OK, I agree that radiation can cause cancer, but how do I know if I will get cancer!!!
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

29. Probability Life Insurance Agent Malpractice Insurance
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

30. How does one determine Probability ?
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

31. Radiosensitivity
Probability of a cell, tissue, or organ suffering an effect per unit dose
Will be greater if the cell:
Is highly mitotic
Is undifferentiated
Younger Cells
This means that children are more sensitive to radiation damage that adults since they have a much higher proportion of rapidly dividing cells. In addition, they life expectancy is much longer meaning that they will live long enough for most latent malignancies to develop into cancer.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

32. Risk versus Age at Exposure
Estimated Risks of Radiation-
Induced Fatal Cancer from
Pediatric CT
David J. Brenner
Carl D. Elliston
Eric J. Hall
Walter E. Berdon
AJR
2001;176:289–296
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

33. LIFE SPAN STUDY Atomic Bomb Survivors
Cancer risk estimate: 4–6% per 1000 mSv (depending on projection method)
! Note: The probability best applies to a group of people and is not suitable for individual cases
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

34. Heritable Effects

35. Heritable effects
Effects to be observed in offspring born after one or both parents had been irradiated prior to conception.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

36. Descendants of Hiroshima and Nagasaki survivors were studied
Heritable effects
Descendants of Hiroshima and Nagasaki survivors were studied
but no statistical abnormalities were detected.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

37. Heritable effects Why so much fuss about genetic effects?
A cohort of 31,150 children born to parents who were within 2 km of the hypocenter at the time of the bombing was compared with a control cohort of 41,066 children.
No indicator was significantly modified by parental radiation exposure.
Why so much fuss
about genetic effects?
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

38. In the absence of human data the estimation of hereditary effects is based on animal studies.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

39. ICRP publication 103 Whole population: 0.2% per Sv Adults: 0.1% per Sv
HERITABLE EFFECTS OF RADIATION
Risks to offspring following prenatal exposure:
Whole population: 0.2% per Sv
Adults: 0.1% per Sv
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

40. …above the prevalent background dose, an increment in dose results in a proportional increment in the probability of heritable effects of  % per Sv of dose.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

41. OK, I understood that these radiation effects have a probability
But, I want to know about ME, if I will get these
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

42. Do you worry about? Yes Not really Yes, Very much
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

43. Do you worry about?
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

44. If you work in such a manner that you adhere to prescribed dose limits of 20 mSv per year for whole working life of 18 to 65 years, your chance of excess cancer is 1 in 1000.
Note: The probability calculations are for a group of people and not for individual cases
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

45. That sounds interesting.
Is it possible to work in such a manner that I remain within 20 mSv/yr?
It should be possible to achieve conditions so that you do not exceed ≈ 3 mSv/yr.
Just wait for later information in this course
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

46. Thank you, that is comforting
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

47. One, Last Question!!!
Are there reports of increased cancer incidence among doctors using fluoroscopy ?
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

48. How can that be possible?
(Not all specialists using fluoroscopy have traditionally interacted with safety and radiation effects professionals)
Let us look into the data for other professional groups like radiologists…
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

49. Radiologists & radiological personnel:
Eight cohorts
3 from US (radiologists, Army X ray technologists, radiological technologists
1 each from China, Canada, Denmark, Japan & UK
Variety of data pertaining to cancer incidence for different sites, mortality data (cancer), now also to other diseases such as cardiovascular
Variation from healthy worker effect to small increase
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

50. UK Radiologists
Around 2700 male radiologists, registered from 1897 to 1979.
Standardized mortality ratio (SMR)
Annual exposure 0.1 Sv before 1950, 0.05 Sv in early 1950’s
Compared mortality rates and death from circulatory disease: Observed number of deaths were generally close to or lower than expected.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

51. US Radiological Technologists
Over 146,000, predominantly females, 73%
Total cancer death rates were lower than expected in general population
Risks higher for those before 1950
Relative risk of mortality from circulatory disease higher for those starting work in earlier years [<1940=1.22, 1940’s=1.00, 1960+=1.00]
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

52. US Radiologists Study
: Cohort with highest exposure, 15% higher mortality from cardiovascular disease than other physicians, after age 55. No information about smoking and other risk factors.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

53. Studies of the Mortality of Atomic Bomb Survivors
An Overview of Cancer and Non-cancer Diseases
Follow up period: 1950–2003
86,611 cohort members
People of both sexes and all ages
Irradiated at different ages
Studies of the Mortality of Atomic Bomb Survivors, Report 14, 1950–2003: An Overview of Cancer and Noncancer Diseases. K Ozasa et al RADIATION RESEARCH 177, 229–243 (2012)

54. Studies of the Mortality of Atomic Bomb Survivors
The sex-averaged excess relative risk per Gy was 0.42 for all solid cancer at age 70 years after exposure at age 30 based on a linear model
The risk increased by about 29% per decade decrease in age at exposure

55. Studies of the Mortality of Atomic Bomb Survivors
Non neoplastic diseases
Significan risks for non-neoplastic diseases of:
Blood (ERR/Gy = 1.7)
Circulatory system (ERR/Gy = 0.11)
Respiratory system (ERR/Gy = 0.21)
Non malignant respiratory diseases (pneumonia and influenza) ERR/Gy = 0.24
Whether these are causal relationships requires further investigation

56. Non-neoplastic effects of Radiation
Risk of Cardiovascular Diseases
following Radiation Exposures
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

57. Non cancer effects
Data from the LSS cohort of Japanese atomic bomb survivors (Ozasa et al 2012*)
excess risk of mortality
ERR/Gy = 0.11, for heart disease overall
ERR/Gy = 0.09, for cerebrovascular disease
*Ozasa et al RADIATION RESEARCH 177, 229–243 (2012)

58. Non cancer effects Threshold for effects Heart disease: no threshold
Cerebrovascular disease: Threshold of 0.5 Gy
However, there is considerable uncertainty about the shape of the dose response at doses below 0.5 Gy
There are excess risks of heart disease for radiotherapy patients with average heart doses of 1-2 Gy (single dose equivalent, after correction for fractionation effects).
Excess risks of cardiovascular disease only become apparent years after exposure at low doses. Long follow-up times are therefore required for assessment of risk

59. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

60. But what about Patient ? He receives tens or 1000 times more than you
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

61. May involve small children, young females and pregnant patients
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

62. Radiosensitivity In Children and Young Patients
Age is a primary determinant of radiosensitivity– the younger the patient, the higher the radiosensitivity
Breast of 15 year old is 15 times more sensitive to radiocarcinogenesis than the breast of 45 year old
Stress that the breast is directly exposed in most cardiac procedures. If not, it is very close to the primary beam meaning that it is receiving high levels of scattered radiation.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

63. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

64. 674 children who underwent cardiac catheterization due to congenital anomalies, between the years
Expected number of malignancies for all sites was 4.75, while the observed number was 11.0
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

65. ICRP statement in its last 2007 recommendations
The available data on possible excess in non-cancer diseases (e.g., cardiovascular disorders) are judged to be insufficient to inform on risks at low doses.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

66. DETERMINISTIC LENS THRESHOLD AS QUOTED BY ICRP
0,5 - 2,0 Sv in SINGLE EXPOSURE
5 Sv in FRAC. EXPOS.
>0,1 Sv/year CONTIN. ANNUAL RATE
OPACITIES THRESHOLD
5 Sv SINGLE EXPOS. > 8 Sv FRAC. EXPOS. >0,15 Sv/year CONTIN. ANNUAL RATE
CATARACT
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

67. IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

68. Re-Cap What can radiation do? Effects that have threshold
No threshold effects - cancer, genetic
Effects at the level of cell, DNA
Probability of cancer, genetic effects
Individual risk
Radiologists, technologists
Patients- Children, young & pregnant female
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

69. Answer True or False
ICRP states that radiation induced cataract can be produced if more than 150 mSv* is received in the lens as a continuous annual rate.
The risk for cancer is 10%/Sv.
Women have slightly higher risk (increase in cancer probability per unit effective dose) than men.
*In a recent statement ICRP (Statement on Tissue Reactions Approved by the Commission on April 21, 2011) the ICRP proposed a limit of 20 mSv/yr, averaged over 5 years, not exceeding 50 mSv at any single year.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

70. Answer True or False
ICRP considers that the available data is insufficient to infer possible non-cancer diseases (e.g., cardiovascular disorders) particularly at low doses.
Breast of a 15 year old women is many times more sensitive to radio-carcinogenesis than the breast of a 45 year old women.
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?

71. Thank you
IAEA Training Course on Radiation Protection for Doctors (non-radiologists, non-cardiologists) using Fluoroscopy
L03. What can radiation do?