IHS - Radiation
Card Set Information
IHS - Radiation
In what measurement is radiation exposure reported?
roentgen equivalents man (REM)
What is REM?
the measure of biologic damage from radiation adjusted to apply to all tissues
What are the two categories of radiation?
What are the 2 types of ionizing radiation?
What are the two types of particulate ionizing radiation?
alpha and beta particles
What are the two types of electromagnetic radiation?
gamma and X-rays
What is the difference between gamma rays and x rays?
gamma rays are from a natural source, x rays are man made
As the wavelength of an electromagnetic wave shortens, its energy _____
Where are alpha and beta particles mainly used?
Does an alpha wave lost its energy in a short or long amount of time?
What stops an alpha wave?
How dangerous is external exposure? how about internal?
external - not dangerous
internal - dangerous if inhaled or ingested
How does a beta particle compare to an alpha particle?
lighter in weight
can be stopped by thin sheet of plastic
can travel through 2 cm tissue externally
Where are beta particles used?
Strontium 90 radiation for eye CA
How do electromagnetic waves behave?
like waves and a particle - cannot bend around corners
What is the energy and ability to penetrate of gamma rays?
high energy, highly penetrating
What stops gamma rays?
lead or concrete
Where are gamma rays used in medicine?
cardiac scans, V/Q scans, Thyoid uptake of iodine 123
How are x-rays expressed?
How does the beam intensity of an X-ray relate to its distance from target?
inversely proportional to the square of its distance
what does mAs tell you about an X-ray?
the QUANTITY of x rays
what does kilovolt peak (kVp) tell you about x rays?
the QUALITY of X-ray
increased kVp = increased penetrability
As kVp increases, scatter ____
What is an early or deterministic dose? What are examples of early radiation exposure?
severity of symptoms are r/t to dose. cataracts, skin injury (sunburn)
What is a late effect or stochastic exposure?
from repeated low doses of radiation over long periods. severity of response is NOT related to intensity of dose.
What tissues are most radiosensitive?
WBC, bone marrow, intestinal epithelium, reproductive cells
sensitivity directly proportional to reproductive activity/cellular metabolic activity rates
What are the least radiosensitive tissues?
mature RBC's, muscle cells, mature bone and cartilage
What is the max annual occupational radiation exposure?
How do you protect yourself against radiation?
Time, Distance, Shielding
What is the recommended minimum distance from the patient being exposed to radiation?
6 ft = 2.5 mm of lead
What does LASER stand for?
Light Amplification by Stimulated Emission of Radiation
What are the 3 ways laser light differs from visible light?
1) Monochromatic (one wavelength)
2) Coherent (oscillates in same phase)
3) Collimated (narrow, parallel beam)
What are the 3 types of lasers?
CO2, Nd:YAG, Argon
Which lasers are invisible to the eye?
CO2 and Nd:YAG
Where does the CO2 laser damage? What type of glasses should you wear?
cornea only. regular glasses with side guards.
What does the Nd-YAG laster damage? What type of glasses should you wear?
opaque green or clear with special coating
What do the KTP and Argon lasers damage? What type of glasses should you wear?
: retina, red filter eye wear
: retina, opaque orange eyewear
How do you protect the patient's eyes from the laser?
saline moistened gauze and laser shields.