Radiology Flashcards
(44 cards)
Which unit of measurement quantifies occupational exposure to electromagnetic radiation?
a. Curie
b. Rad
c. Rem
d. Roentgen
C. Rem
A roentgen is a
unit of radiation exposure
-describe the output intensity of an x-ray machine
A radiation absorbed dose or a RAD is
the quantity of radiation received by an individual
A REM or radiation equivalent man is a
unit of occupational radiation exposure
A Curie is a
quantity of radioactive material
X-rays are a form of ___________________ that penetrate matter at the molecular level
short wavelength, high frequency ionizing radiation
In addition to providing images of internal structures, X-ray exposure can
damage cellular components (RNA, DN), create reactive oxidative species, and predispose a person to cancer
These tissues are at very high sensitivity for radiation damage:
bone marrow, intestinal epithelium, reproductive cells
These tissues are at high sensitivity for radiation damage:
optic lens, thyroid epithelium, mucus membranes
Safety precautions for radiation include
stand at least 3 feet away from the X-ray source and use lead shielding (apron, thyroid shield, goggles)
The only effective barriers against X-rays and gamma rays are
lead and concrete
A roentgen is thought of as
the total dose administered
A Rad is thought of as
the total dose received at the tissue level
A Rem can be thought of as the
“effective dose”
The yearly maximum radiation exposure for adults is
5 rem
The yearly maximum exposure for the fetus of a pregnant work is
0.5 rem or 0.05 rem/month
The features of the X-ray beam required for a radiograph depend on the following three things;
patient’s body weight and habitus
density of body part being examined
orientation of the X-ray beam relative to the patient
The three ways to limit radiation exposure include
distance
duration
shielding
The minimum safe distance from the radiation source is
six feet
Which features will be present in a normal chest X-ray?
a. domed hemidiaphragm
b. heart borders >60% of chest width
C. blunted costophrenic angles
d. left hilum slightly higher than right
A & D
Describe the ABSCDEFGHI pneumonic to systematically review chest X-rays
A= assess film quality & airway
B= bones and soft tissue
C= cardiac
D= diaphragm
E= effusion
F= fields, fissures, and foreign bodies
G= great vessels and gastric bubbles
H= Hila and mediastinum
I= impression
In a normal CXR describe what you should expect of the bones and soft tissue
bones= intact bilaterally
soft tissue= free from air and edema
In a normal CXR describe what you expect of the heart
cardiac size, shape, and aortic knob within normal limits
Hemidiaphragms are part of a normal CXR and appear
domed with the right usually higher than the left