x-ray with shorter wavelengths penetrate__ than rays with longer wavelengths
farther
electons travel__
toward the anode in an xray tube
in x-ray tubes, the majority of energy produced by the movement of elevtrons is in the form of__
heat
on the electromagnetic spectru, in relation to visible light, x-rays__
have a shorter wavelength
What are two names for bdles of energy that ravel in a wave?
photons, quanta
Filamnents located in an x-ray tube emit__ when heated
electrons
the anode's target is composed of__
tungsten
The anode's target reaches temeratures in excess of __ during x-ray production
1000 degrees C
the anode's targer usually has a __ base
copper
Which kind of anode is unable to withstand large amounts of heat?
stationary anode
Veterinary patients have a tendency to move while being positioned for radiographs to be taken. The radiographer should help to safely prevent artifacts of movement by__
using the shortest exposure time possible
x-ray tube ratings are based on target angle, focal spot size, elevtrical current (single- or three--phase operation) and:
anode speed
Which of the following is a type of somatic damage caused by radiation? a. gene mutation b. cataracts c. sterility d. none of the above
cataracts
__ damage is not detectable until future generations are produced
genetic
What is the upper limit of exposure that an occupationally exposed individual may receive according to state and federal regulations?
0.05 Sv/year
A type of dosimeter designed to monitor that actual amount of radiation received
Film badge
What type of dosimeter can be stored for years, maintaints its information, and can be reused?
Theromluminescent dosimeter
What does scatter depend on?
the intesnsity of the beam, the compostion of the structure being radiographed and kilovoltage level
The most conclusive method used to inspect lead-lined gloves and aprons for crack and defects is__
Taking a radiograph of it
What is the thickness of the lead-impregnated rubber lining protective appareal in veterinary radiography?
0.5mm
How might you increase penetrating power of the x-rays?
increaseing kVp
The milliamperage-seconds (mAs) for 1000mA and 1/10 sec is:
100 mAs
According to Santes' rule, is a cat's abdomen measures 12 cm, kVp is:
64
The source-image distance most commonly ranges from__ in veterinary practices
36-40cm
one percent of the energy produced at the anode is in the form of__
x-rays
The temperature of the filament within the cathode is controlled by:
mA setting
An xray's intensity __ as SID decreases
increases
the potential difference between the anode and cathode is measured in:
kilovolts
a higher kVp setting allows for a __ mAs and __ exposure time
lower; lower
What does thicker body parts do to the radiographic density?
increases it
High subject contrast __ radiographic contrast
increases
The primary exposure factor that controls scatter radiation
kVp
What do grids contain that contols scatter radiation?
lead
Where is a grid located?
between the patient and the cassette
To prevent magnification and distrotion of the object being radiographed, the patient must:
be as parallel and as close to the film as possible
if a god is being radiographed for hip dysplasia, what phenomenon will occur if the femurs are not parallel to the film?
foreshortening
The walls of the darkroom should be white or cream colored because:
more reflection of the safelight is produced, providing a more visible working environment
Which of the following is true regarding safelights? a. they should be 20 watts or less b. they must be at least 4 feet from the work area c. the brown filter is for blue-light-sensitive film d. film can be exposed to safelights indefinitely with no ill effects to the film
b. they must be at least 4 feet from the work area
What is the ideal pH at which to develop radiographs?
9.8 to 11
Unexposed silver halide crystals remaining on films are removed at this stage:
fixing
Advantages of automated film processing include: a. consistent quality of processed radiographs b. dry radiographs are produced in a short time c. a much smaller space is necessary d. all of the above
d. all of the above
These two by products of development contain silver that cannot be disposed of in a septic systems:
radiographs and fix solution
Which of the following is no required on the label ID of a radiograph? a. initials of radiographer b. date taken c. patient name and owner name d. name and address of hospital
a. initals of radiographer
All of the following are legally valid methods of labeling a radiograph except: a. lead-impregnated tape b. lead marker c. premanent marker after development d. photoimprinting label system
c. permanent marker after development
The conversion of x-ray into visible light occurs via:
intensifying screens
To absorb backscatter, the back of most cassettes are lined with:
lead
Intensifying screens allow:
a lower mAs to be used
The main advantage of today's rare-earth-coated intensifying screens is:
they have a higher x-ray-to-light conversion efficency
Which of the following statements is true? a. screen film is more sensitive to ionizing radiation b. nonscreen film produces poorer detail c. nonscreen film is highly sensitive to fluroescent light emitted from intensifying screens d. nonscreen film requires greater exposure
nonscreen film requires great exposure
True/False: both the fluroscopic image and x-ray image viewed on a view box are considered positive images because they intensity of light emitted by each part of the screen is proportional to the amount of x-rays striking that part of the screen
false
a processing film that has been exposed to ionizing radiation or visible light will appear:
black
Which of the following are appropriate storage conditions for radiographic films?
10 to 15 C 40% to 60% humidity, vertical
Which of the following film-screen systems is most commonly used in veterinary medicine?
Medium speed system
true/false: the radiographer must recover silver in the veterinary clinic
false
the most effective types of darkroom doors include: a. doors that do not lock b. revolving door system. c. double door system d. both b and c
both b and c
The degree of blackness on the radiograph is:
density
Density is determined primarily by:
mAs
Radiographic contrast is determinded primarily by:
kVp
If a radiograph includes many shades of gray, which of the following is also true regarding the image?
low contrast, high kVp
When viewing a radiograph of a laterally positioned animal: a. the head should be at the top of the view box b. the head should face the viewer's left with spine at the top c. the head should face the viewer's right with the spine at the top
b. the head should face the viewer's left with the spine at the top
an overexposed film appears __; to correct this, __
too dark; decrease mAs or kVp
What action should be taken if it is difficult to see anatomic silhouettes on an abdominal film and the film is too light? why?
increase kVp by 10% to 15%; shorten wavelength, increase penetrating power
You have determinded that penetration in adequate for a particular abdominal film. All abdominal structures are well outlined. However, the film has an overall appearance of being too light. What should you do next?
increase mAs by 30% to 50%
A thoracic film is too dark the bone tissue is relatively white. What is the next step?
decrease mAs by 50%
How does kVp affect scatter radiation?
as kVp increases, scatter radiation can increase
Any body part exceeding this measurement requires the use of a grid to reduce for-producing scatter radiation
10 cm
when taking a test radiograph, the following requirements should be met:
medium-speed film, 50lb dog in a lateral position
According to the author, when developing a varible kVp technique chart, kilovoltage should be increased or decrease by increments of __ for each centimeter measurement
2
Which of the following conditions may require decreasing the mAs to account for increased radiographic density? a. neonatal animals b. ascites c. pleural effusion d. plaster casts
neonatal animals
If a radiograph is too light after taking a view of the later abdomen what change may be recommended?
increase mAs 30% to 50%
Compared with the abdomen, how much mAs does a quality view of the pelvis require?
30% to 50% more
A grid with a ratio of 12:1 will be used with the machine at your clinic. How does this affet the generation of your variable kVp chart?