Exam 1 Flashcards
What was x-ray originally known as?
Roentgen ray
Who discovered x-ray?
Wilhelm Conrad Roentegen in 1895
What was the first x-ray done of?
Bertha’s hand
When was x-ray first introduced into chiropractic and by whom?
BJ palmer in 1910
T/F all x-rays have predictable qualities
True
Distance either…
a. reduces intensity
b. increases intensity
a
What is the main cause of image distortion?
divergence
T/F x-rays are stored in matter
false
T/F x-rays cannot be focused, reflected or refracted
True
What are the three things that are needed to give birth to an x-ray?
- source of electrons
- a way to accelerate them to a high speed
- a hard surface to stop them
The three things necessary for an x-ray are included in what part of the tube?
a. tube
b. filter
c. collimator
d. grid
a
What is the name of the device that limits the size of the x-ray beam?
callimator
What is the purpose of the grid that is behind the patient?
stop the secondary waves
put the following in order….
collimator, film, cassette, patient, screens, grid, tube, filter
tube, filter, collimator, patient, grid, cassette, screens, film
__________ means producing x-ray images
radiography
____________ interpreting x-ray images
radiology
What type of radiation is produced with x-rays?
Electromagnetic energy
EMR is typically measured in?
a. electron volts
b. hertz
c. meters
a
EMR frequency is typically measured in?
a. electron volts
b. hertz
c. meters
b
EMR wavelength is typically measured in?
a. electron volts
b. hertz
c. meters
c
What is another name for photons?
quanta
T/F EMR travels at the speed of light
have no mass
travel individually
T
T
F
What are the two type of radiation that EMR is divided into?
ionizing and non-ionizing
ionizing radiation usually has
a. long wave and low frequency
b. long wave and high frequency
c. short wave and low frequency
d. short wave and high frequency
d
Which type of radiation is harmful?
a. ionizing
b. non-ionizing
a
What is a beam limiting device of today?
Collimator
What is the purpose of the collimation?
limit size of primary beam
limit secondary rays
What do secondary waves do to an x-ray?
causes graying and darkening
What is the purpose of a compensating filter?
attenuates the beam to lessen intensity to thinner parts
Where are portal filters usually found?
in front of the beam limiting device (callometer)
What are compensating filters usually made of?
aluminum and copper
A patients ID marker is required on the film before processing?
True
The name of the facility that took the x-ray should be included or the __________
Doctor responsible
What four things are required on an x-rays ID marker?
Name of the facility or the Drs name
Address of that facility
Name and/or identifying patient
Date of the study
What are four things that are not required to be ncluded on the x-ray but is nice to have?
sex
region x-rayed
view taken
date of birth
What is the best method to apply an ID marker to an x-ray?
flash on printer
ID markers are usually ________ and put on ________ or _______
lead; grid cabinet or cassette
On frontal and oblique projections R and L are put on __________
The patients right or left side
on lateral views an R or an L is placed on which side?
The side that is closest to the film
T/F When placing a marker on the patient, the upright position should be designated.
True
What kind of Marker tells R or L and recumbent or upright?
Mitchell
T/F markers should be included in the anatomy.
False
What should be done if an x-ray has no marker on it?
it may need to be retaken in order to make it legal
not electromagnetic but has ionizing ability…
particle radiation
particle radiation comes from what?
decay of a radioactive atoms nucleus
alpha and eta particles are more or less penetrating than x-ray
less
alpha and beta particles are more or less harmful than x-rays
more (when inhaled)
measuring ionizing radiation is known as…
dosimetry
what performs dosimetry?
dosimeter
How is ionizing radiation measured?
roentgen or coulombs
What does RAD stand for…
aka?
Radiation absorbed dose
Gray
how many rad units to 1 gray?
100
1/1000 of a rad is known as…
millirad
How are RADs normally used?
biological effects of radiation to specific organs and tissues
What does REM stand for?
aka
Radiation equivalent man
sievert
What is rem used for?
used for radiation detection in reporting exposure
dosimetry for workers is usually in the form of what?
film badges
What is not used with x-ray?
a. roentgen
b. RAD
c. REM
d. Curie
d
what are the sources of natural ionizing radiation?
cosmic
terrestrial
internal
What are the sources of man made radiation?
Diagnostic x-ray
nuclear medicine
Consumer products
Nuclear testing/reactors
what percentage of our yearly radiation exposure is made of background radiation?
82%
three important points about cosmic radiation
- exposure from sun and stars
- higher altitude increases exposure
- increases further the latitude from the equator
terrestrial radiation is aka?
external terrestrial
Radon is a form of what type of radiation?
terrestrial
What are some sources of terrestrial radiation?
soil, rocks and mountains, brick wallboard and cement
55% of our total yearly radiation comes from what?
Terrestrial radiation
internal radiation comes from what?
nuclides
how do we get internal radiation?
ingested from food and water
what percentage of our yearly dose of radiation come from man made products?
18%
What is the largest source of manmade radiation?
Diagnostic x-ray
t/f
long term effects f low levels of radiation are definitive.
false
What is the theory that any amount of x-ray exposure is harmful?
the linear theory
What are the types of radiation doses?
Whole body dose skin entrance dose organ dose somatic dose Genetic dose fetal dose stochastic somatic dose deterministic somatic dose protraction fractionation radiation hormesis
What is the more detrimental type of radiation exposure?
a. whole body
b. skin entrance
c. organ dose
d. somatic dose
whole body dose
T/F the deeper the tissue the less exposure
True, this is due to absorption
what are the symptoms of a somatic dose?
hair loss and erythema
What type of dose can cause damage to a future generation?
Genetic dose
T/F
The patient is being irradiated when hit with genetic dose of radiation
false, future offspring
What are the greatest effects of genetic dose
leukemia and mutation
T/F
A radiation physicist can calculate a fetal dose of radiation
True
a fetal exposure of up to ________ is not expected to cause any effects on the newborn
10 rads
What are stochastic somatic effects?
long term effects such as cancer and cataracts
radiotherapy and radioactive implants are examples of what?
protraction, low level continuously, effects are reduced
also used in radiotherapy, non continuous exposure to high doses reduces effects
fractionatioin
the apparent beneficial effects of radiation
radiation hormesis
T/F all radiation is harmful
false
T/F
small-moderate doses of radiation may reduce infection and fatal malignancies and prolong life
true
200-1000 rads acute whole body
hematological syndrome
1000-5000 rads
gastrointestinal syndrome
5000 rads and over
central nervous system syndrome
What does ARS stand for?
Acute radiation syndrome
What are the stages of ARS?
- Prodromal stage
- Latent stage
- Manifest stage
- healing or death
What dose LD 50/60 mean?
Lethal does 50% of the time in 60 days
What is a humans lethal dose?
LD 50/60 of 350 rads without medical intervention
LD 50/30 for us is 300 rads
Are x-rays stored in matter and make it radioactive?
no
What is the metal encasement around the tube?
Tube housing
What are the parts of the tube complex?
Tube support
glass tube
cathode
anode
the tube housing is lined with ________?
lead
What does the lead do that lines the tube housing?
prevent leakage or radiation
protects the glass tube that is inside
What surrounds the tube in the tube housing?
what does it replace?
oil
air
what is the purpose of the oil in the tube housing?
dissipate heat (thermal insulator)
What is the opening in the tube housing called?
window or port
What are the parts of the tube support?
tube housing
tube arm
tube stand
tube track
What holds te tube housing in position?
Tube arm
What holds the tube arm and what is its purpose?
tube stand
allows the arm to move the tube vertically
What allows the tube travel horizontally?
tube track
What are the four ways that the tube track can be mounted?
floor mount
ceiling mount
floor-ceiling mount
C-arm (no track)
What holds the arm and stand in position?
Automatic locks
What contains the functional parts of the tube?
The glass tube
the glass tube has a _______ glass area for the window (_________ to penetrate)
a. thinner; difficult
b. thinner; easier
c. thicker; difficult
d. thicker; easier
b
what are the rays exiting the window called?
useful beam
The centermost ray is called?
Central ray
The central ray is __________ to the patient
a. perpendicular
b. parallel
a
The other rays that angle away from the central ray are known the __________
diverging rays
divergence of rays ____________ the more the central the beam
a. decrease
b. increase
a
The negative electrode is known as?
cathode
What is the electron producer?
cathode
what are the three functions of the cathode?
produces electrons
focuses electrons
propels electrons
What are the two parts of the cathode?
filament
focusing cup
What is the filament of the cathode normally made of?
tungsten
What is the function of the filament?
withstand the heat
What heats the filament of the cathode?
a current
how is the current produced in the cathode?
by the filament or milliamperage circuit
When heated electrons from the tungsten are boiled of it is called…
thermionic emission
how is the amount of electrons controlled?
by the current
What does the number of electrons formed control
the number of x-rays
What is the cloud of electrons around the filament called?
a space charge
most cathodes have 2 filaments, small and large, this is called?
the small produces
the larger produces
dual focus tube
clearer images
less clear image(handles more heat)
what is the indentation that a filament sits in?
focusing cup
What is the focusing cups function?
consolidates the electron cloud
what propels electrons across the tube
an electrical current
what propels electrons across the tube?
an electrical current
What is the positive electrode?
anode
what does the anode produce?
photons
What are the 3 functions of the anode?
Stops electrons thus produces x-rays
dissipates heat
conducts electricity
the anode stops electrons and thus produces x-rays, what percentage of x-rays make up these
What makes up the rest?
1%
99% heat
What are the 3 parts of the anode?
some machines don’t contain what part
target,stem and rotor
rotor
What is the anode made of?
tungsten
X-rays are emitted from…
the focal spot
What does a dual focus tube contain?
small focal spot and large focal spot
What are the two types of focal spots
actual and effective focal spot
which focal spot is where the electons strike?
actual focal spot
What focal spot do photons exit?
effective focal spot
What do large spot produce?
What does the small spot produce?
penumbra (unclear borders)
umbra (clear borders)
What are the functions of the stem?
holds the target and conducts heat away from it
what is the stem made out of?
copper
What are the 2 types of anodes?
stationary anode and rotation anode
What is the angle of the anode called?
What is the purpose of it?
anode angle
dissipate heat
What anode is used for small exposures?
stationary anode
Which anode has the greater angle?
a. stationary anode
b. rotating anode
Which is more effective at dissipating heat
a
b
What is the sound that is heard before an exposure?
the rotor rotating the anode
What is another name for the focal spot
focal track
Which makes clearer images
a. larger angles
b. smaller angles
b
What the line focus principle?
smaller angles produce clearer images than larger ones
Which is up? the anode or the cathode for a full spine
the anode
What is the interaction of an incoming electron with a target nucleus called
bremstrahlung radiation
What happens when an electron course is changed
the electron loses energy
the energy lost when an electron changes course is converted into?
an x-ray
make up the majrity (85%) of the x-ray beam
What shell does the incoming electron hit?
The K shell
What does filtration do?
reduces patient exposure
What are the two type of tube filtration?
inherent and added
Filtration __________ the beam intensity
attenuates
What does filtration eliminate?
soft rays
What do soft rays do?
increases the skin entrance and organ dose
what is soft rays measured in?
measured in aluminum thickness, this allows hard rays to get through
the amount of material needed to reduce the beam intensity by half
half value layer
what is half value layer used for
filtration recommendation and regulations
The enter of the beam is shown by horizontal and vertical lines, this is called_________________
cross hairs
What are the three basic type of collimation?
What are positive beam limitations?
manual
semiautomatic
automatic
semiautomatic
automatic
it the tube is too high or the film is too low where is the cut-off
the bottom
if the tube is too low or the film is too high the cut off is where?
at the top
What does filtration do?
improves the quality of the film
Where are portal filters placed?
on the front of the beam limiting device
what are portal filters normally made of?
aluminium, or copper
what kind of filter would be used to taper off an image?
a wedge filter
which filter exposes the patient to unneeded exposure?
underpart filter
Machine come with what to prevent tube failure?
What is used to make calculations?
a tube rating and tube cooling charts
heat units
how do you warm up your x-ray?
use 2 low exposure (low kV, short time and medium mA, double for second exposure)
how many volts and amps are traditionally in a generator?
220 Volts and 100 Amps
What changes incoming current?
transformers
A high voltage transformer convert volt to ___________
kilovolts
A high voltage transformer is also known as…
step up transformer or high voltage circuit
a filament circuit converts amps to ___________
milliamps (mA)
a filament circuit is also called a…
filament transformer
low voltage circuit
step down transformer
What do rectifiers to?
change current from AC to DC
why is alternating current not good for x-rays?
move current in both directions, a reverse in electrons would destroy the cathode
rectifiers are aka
diodes
which is more efficient?
a. half wave rectification
b. full wave rectification
b, sends two positive pulses
how is the kV set
kilovolt peak
The build up of kV to the peak and the return to 0 is known as what?
ripple
what type of generator has 1 line source and a maximum ripple?
single phase generators
What are the three types of generators?
single phase
3 phase
high frequency
which type of generator has virtually no ripple?
high frequency generators
What does a timer circuit do?
controls the length of exposure
what kinds of timers on timer circuits are there?
synchronous, electronic, mAs and automatic exposure control
which timer has photocells?
automatic exposure control
What are the four primary factors controlling x-ray exposure?
Kilovoltage peak (kVp)
mlliamperage (mA)
length of time of exposure
distance of the tube from the receptor (film)
increasing the kVp does what to the film?
darkens it
increasing the mA does what to the film?
darkens the film
increasing time of exposer does what to the film
darkens it
the distance of thtube from the receptor (film) influences x-ray exposure, what are some other names that it is known by?
source-image distance and focal-film distance, occasionally target-film distance
what does increasing the distance from the film do to the film?
lightens
beam intensity ___________ with increased distance
decreases
What are the two standard distances away from the x-ray?
40 and 72”
mAs need at 72” is roughly how much more than at 40”?
3x
What are some secondary factors that influence x-ray exposure?
field size
compensating filtration
T/F patient dose limit exists but it should be as low as possible
true
shields on the collimator are called?
shadow gonad shields
shields on the patient are called
contact gonad shields
full spine x-rays should be
a. P-A
b. A-P
P-A
T/F The younger the person the higher the metabolic rate and the less radiosensitive the person is
false
the ten day rule in regards to the safest time to x-ray females of childbearing years is obsolete
true
