3. Rutherford's Vascular Surgery and Endovascular Therapy,
Chapter 74, 3183-3221.e
Textbook
Journal
- Meisinger, Q. C., et al. (2016). "Radiation protection for the fluoroscopy
operator and staff." American Journal of Roentgenology 207(4): 745-754.
- Ho, P., et al. (2007). "Ionizing radiation absorption of vascular surgeons
during endovascular procedures." Journal of vascular surgery 46(3): 455-
459.
- Kim, J. B., et al. (2017). "Radiation hazards to vascular surgeon and
scrub nurse in mobile fluoroscopy equipped hybrid vascular room." Annals
of surgical treatment and research 92(3): 156-163.
REFERENCE
4. TYPES OF RADIATION
• Ionizing radiation
• Radiation capable of producing ions
• Comes from x-ray machines, nuclear reactors, and
radioactive materials
• Non-Ionizing radiation
• Comes from microwaves, sound waves, light, lasers,
radiofrequency, electromagnetic fields, etc.
5. IONIZING RADIATION
• Consists of alpha and beta particles,
neutrons, and energetic photons (ultraviolet
and above)
• which contain sufficiently high energy to
interact with atoms and produce biologic
injury.
• The most common forms of ionizing
radiation used in medicine are x-rays,
gamma rays, beta rays, and electrons
6. PENETRATING ABILITIES
• ALPHA - very limited ability;
short range in air, stopped by
skin
• BETA - function of originating
energy; can penetrate skin
• GAMMA - highly penetrating;
can reach all body organs
7. FORMS OF IONIZING
RADIATION (CONT.)
• GAMMA
• Deep penetrating
• Need steel, lead, etc. to shield
• X –Radiation
• Commonly thought of as electromagnetic radiation
produced by an x-ray machine
• Penetration depends on wavelength and material being
irradiated.
• Often use concrete to shield
9. - measured in C/kg or Roentgen(R)
- amount of charge (electrons) liberated per kilogram
of Air (Ionization)
1R = 2.58x10-4 C/Kg
EXPOSURE
10. - measured in Gray (Gy) or Rad
- amount of energy deposited/ absorbed per kilogram
of tissue
1Gy = 1 Joule/Kg
100 Rad = 1 Joule/Kg
1Rad = 1/100 Gy
ABSORBED DOSE
11. - measured in Sieverts (Sv) or Rem
- amount of biological damage
- gives a measure dose as if received by the whole
body
- used to equate dose to risk
1Sv = 1 Joule/Kg
100 Rem = 1 Joule/Kg
1Sv = 1/100 Rem
EFFECTIVE DOSE
12. BIOLOGIC EFFECTS OF RADIATION
•Classified as two types:
•Deterministic effects
•Stochastic effects.
13. DETERMINISTIC
EFFECTS
• Dose dependent and
result in cell death
• Occurs when a threshold
level of radiation has
been exceeded, and the
higher the dose, the
greater the injury
14. HUMAN RESPONSES TO IONIZATION RADIATION
Acute Radiation Syndrome Hematologic Syndrome
Gastrointestinal syndrome
Central nervous system
Local Tissue damage Skin
Gonads
Extremities
Hematologic depression
Cytogenic damage
EARLY EFFECTS
15. Acute Radiation Syndrome Hematologic Syndrome
Gastrointestinal syndrome
Central nervous system
Other malignant disease Bone cancer
Lung cancer
Breast cancer
Leukemia
Genetically significant dose
Lifespan shortening
HUMAN RESPONSES TO IONIZATION RADIATION
LATE EFFECTS
16. Photograph of the patient’s
back 6-8 weeks after multiple coronary
angiography and angioplasty procedures.
Photograph of the injury 16-21 weeks after
the procedures. A small ulcerated area is
present.
DETERMINISTIC EFFECTS
17. Close-up of the lesion shown in C
Photograph of the patient’s back 18-21 months
after the procedures. Tissue necrosis is evident
DETERMINISTIC EFFECTS
18. Photograph of the patient’s
back after Grafting.
DETERMINISTIC EFFECTS
19. STOCHASTIC EFFECTS
• Cause DNA damage to single cells -- mutation.
• This is an all-or-none phenomenon,
The severity of the effect of mutation is unrelated to the
dose.
• Mutations lead to
cancer
birth defects
genetic effects
26. Reduce of your exposure
Increase from the source
Make use of available
TIME
DISTANCE
SHIELDING
General Radiation Safety
27. • Minimize time in radiography or fluoroscopy rooms
• Minimize time spent with patients who are undergoing therapy
treatment
• Know Your Protocol
Read the procedure through carefully
Understand the steps clearly or
Have the protocol displayed where you can see it
Do not depress the footswitch continually for long periods
Use pulsed fluoroscopy modes
• Practice the technique beforehand
Time
31. Fluoro only when viewing monitor
Use pulsed fluoroscopy when possible
Use last image hold
Methods to reduce dose
to patients and personnel
32. Shielding
Personal shielding
lead aprons - at least 3 - 5mm Pb
equivalent
provide up to 90% shielding.
thyroid / eye shielding during fluoroscopy
lead glove (5mm + Pb eq.) if hands are
likely
to be in the beam
Lead drape on fluoro tower provides an
additional 90% protection of the
remaining 10% from lead aprons above.
39. The distance between
patient and image
detector should be
minimum and
maximum between
patient and the source.
Position
40. TUBE
ANGULATION
Work practices
• Steep angulations – LAO
45o CAU 35o
• Demands more radiation
for imaging
• Increases staff dose
• Increases patient dose
41. WORK PRACTICES
• • Excessive use of
image
magnification increases
radiation doses
• Use image
magnification modes
judiciously
42. ENDOVASCULAR PROCEDURE
Kim, J. B., et al. (2017). "Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular
room." Annals of surgical treatment and research 92(3): 156-163.
43. ENDOVASCULAR PROCEDURE
Kim, J. B., et al. (2017). "Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular
room." Annals of surgical treatment and research 92(3): 156-163.
44. ENDOVASCULAR PROCEDURE
Kim, J. B., et al. (2017). "Radiation hazards to vascular surgeon and scrub nurse in mobile fluoroscopy equipped hybrid vascular
room." Annals of surgical treatment and research 92(3): 156-163.
45. RADIATION AND PREGNANCY
Risk of
• Spontaneous abortion (15%)
• Genetic abnormalities (4%-10%)
• Birth malformations (2%-4%)
46.
47. RECOMMENDATIONS FOR PREGNANT
WORKERS
The National Nuclear Commission guideline :
• No more than 5 mSv of equivalent dose
exposure during the entire pregnancy
• less than 0.5 mSv/mo.
48. CONCLUSION
• Use radiation safety accessories
when required.
• Use personal monitoring
devices
• Follow the basic principles of
radiation safety
• Follow radiation dose reduction
techniques
• Radiation safety awareness and
training program
The ICRP recommends a dose limit of 1 mSv/yr to the general public.
For radiation workers, an effective dose limit is 20 mSv/yr, averaged over 5 years and not exceeding 50 mSv in any single year.Additional exposure limits for the ocular lens and extremities of workers are defined separately the risk of health effects is too small to be observed at doses below 50 to 100 mSv/yr.
When x-rays enter through the body surface most of the energy is absorbed by tissues
while some amount is scattered from the body surface (eg., patient).
• Staff are are exposed to these scatter (secondary) radiation
Personnel should always maintain a distance from the x-ray tube and keep the image intensifier as close to the patient (and the tubeas far away) as possible to reduce patient skin dosage.
The amount of scatter radiation decreases with the square of the distance fromthe tube (exposure = 1/d2);
Transfemoral procedures will therefore incur less exposure than transbrachial procedures will
A, Photograph shows ceiling-suspended shield.B, Photograph shows table skirt.C, Photograph shows mobile shield on wheels.
Fig. 3—Common styles of lead personal protective aprons.A and B, Photographs show front (A) and back (B) of two-piece apron with wraparound skirt and front entry vest. Garment also has left arm shield.C and D, Photographs show rear-entry single piece apron with full front (C) and back (D) coverage.E and F, Photographs show front (E) and back (F) views of rear-entry single-piece apron with open back.G and H, Photographs show whole-body (G) and close-up (H) views of poorly ftting oversized apron resulting in exposure through left arm hole.Downloaded from www.ajronline.org by Mahidol Unive
Fig. 5—Ceiling-suspended radiation protection designed to minimize both radiation exposure and body strain. (Courtesy of CFI Medical Zero Gravity)A, Photograph shows components of system.B, Photograph shows system in use
• Thermo-Luminescent Dosimeters• Real-time monitoring devices• Pocket dosimeters• Area surveillances using survey meters