1. Health and Biological Effects of Radiation
Elsevier items and derived items © 2009 by Mosby, Inc., an affiliate of Elsevier Inc.

2. Radiation risks: Non-stochastic
Commonly referred to as deterministic or somatic effects.
Threshold-related symptoms worsen with dose
Skin changes: erythema /hair loss/ulceration
Cataracts
Teratogenesis

3. Radiation risks: Stochastic
Also known as genetic
Non-threshold, increasing probability with dose
Severity of condition independent of dose
Genetic mutation
Genomic instability
Cancer induction

4. Genetic Effects of Radiation Exposure
Linear, nonthreshold response
All mutations are harmful
Exclusively naturally occurring mutations
Dependent on fractionation and protraction
Females less radiosensitive than males
Most mutations are recessive

5. It is possible to inflict damage during radiology procedures!
A subtle and disturbing aspect of radiation damage can be the delay in its manifestation. One cannot automatically assume that when such damage occurs long after a fluoroscopy study, that it's cause will be associated with the study. It is highly probable that there are fluoroscopists who have inadvertently caused radiation burns to a patient and are not aware of injury inflicted.
16-21 weeks post- fluoroscopic procedure
18-21 months post procedure
Close-up
Courtesy FDA Web Site:

6. Patient Dose Factors / Considerations
Fluoroscopic exposure time or # of radiographic exposures
Beam parameters
Intensity
Penetration
Distance from x-ray tube
Beam size
Sensitivity of exposed organs
damage threshold
It is the responsibility of the fluoroscopist to minimize fluoroscopic exposure within clinical limits as well as to understand the associated risks to the patient Fortunately many of the issues just discussed which reduce operator exposure also reduce patient exposure. Although some actions reduce both patient and operator exposure and improve image quality, unfortunately, some actions which reduce patient exposure also degrade the image quality.
The principle source of radiation to patients is the primary beam, radiation coming directly from the x-ray tube. Exposure for a particular patient depends upon the beam's intensity, the length of time the beam is on, the distance of the patient from the x-ray tube, the collimation of the x-ray beam. Different organs exhibit different sensitivities to radiation. Damage thresholds to various organs can be exceeded. In fluoroscopy skin is often the critical organ in terms of the amount of radiation received and the threshold for damage.

7. Risk Estimates Relative risk Excess risk Absolute risk
Observed cases/Expected cases
Excess risk
Absolute risk
# Cases/106 persons/rad/yr

8. Radiation Induced Leukemia
Latent period = 4 to 7 years
At-risk period = 20 years

9. Radiation Induced Cancers Observed in Irradiated Populations
Thyroid cancer
Thymus irradiation
Rongelap Atoll nuclear test
Bone cancer
Radium watch dial painters
Radium salt treatment
Skin cancer
Orthovoltage radiation therapy
Breast cancer
Tb treatment
A-bomb survivors
Lung cancer
Uranium miners
Liver and spleen cancer
Thorotrast

10. Effects of 200 rad in Utero

11. Expected Days of Life Lost
Risky Condition
Expected Days of Life Lost
Being male rather than female
2800
Heart disease
2100
Being unmarried
2000
One pack of cigarettes a day
1600
Working as a coal miner
1100
Cancer
980
30 pounds overweight
900
Stroke
520
All accidents
435
Service in Vietnam
400
Motor vehicle accidents
200
Average occupational accidents 74
Speed limit increase from 55 to 65 mph 40
Radiation worker 12
Airplane crashes 1

12. What’s Next?
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