Medical Imaging Exam #1 UPDATED
ACTUAL Exam Questions and CORRECT
Answers
Who discovered x-rays? - CORRECT ANSWER - Conrad Roentgen
accidental discovery while investigating emissions from Crookes tube
used almost immediately in medical field
form of electromagnetic radiation energy of extremely short wavelength - CORRECT
ANSWER - x-ray
the shorter the wavelength, the _______ - CORRECT ANSWER - greater its energy and
the greater the ability to penetrate various materials
How are x-rays measured? - CORRECT ANSWER - electron volts
How does x-ray work? - CORRECT ANSWER - 1) produced when an electron beam hits a
metal target
2) beam and target are enclosed in a device called x-ray tube
3) x-ray tube has special window to allow x-rays to escape (controls size of beam)
4) directed at x-ray film that is placed behind the patient
Absorption of x radiation depends on - CORRECT ANSWER - substance's density and
atomic weight
,lower the atomic weight/density, the more transparent it is to x-rays
the degree to which x-rays are absorbed/deflected by the body part - CORRECT
ANSWER - attenuation
The ______ attenuate more radiation than the surrounding tissues - CORRECT
ANSWER - bones
higher density = heavier "shadows" of x-ray film
Dark area on x-ray =
Light area on x-ray = - CORRECT ANSWER - dark = less dense, more x-ray went
through (air)
light = more dense, less x-ray went through (bones, solids)
Radiopaque = - CORRECT ANSWER - more dense, light
ex: bones
Radiolucent = - CORRECT ANSWER - less dense, dark
ex: lungs
What are the four types of radiographic densities? - CORRECT ANSWER - 1) Gas (Air) =
black
2) Fat
3) Water
,4) Bone = white
ex: water = soft tissue
if water in the lungs, will turn the film more white
What factors affect image quality? Which ones should we pay attention to the most as a
clinician? - CORRECT ANSWER - 1) Thickness of the body part
2) Motion
3) Scatter
4) *Magnification*
5) *Distortion*
How does motion effect the x-rays? - CORRECT ANSWER - causes blurring
overcome by: shortening the exposure time, using an intensifying screen that is found in all film
holders
How is scatter produced in x-ray? - CORRECT ANSWER - deflection of some of the
primary x-ray beam
grid is used to reduce scatter
How does magnification effect the x-ray results? - CORRECT ANSWER - as an object
moves toward the x-ray, the shadow becomes larger
-The closer the patient is to the film, the more true to size the organs will be.
-If the patient is further away, it will appear falsely enlarged
, How does distortion occur when taking an x-ray? How do you confirm the x-ray is not distorted?
- CORRECT ANSWER - when the object is NOT perpendicular to the x-ray beam
this makes it appear that two things are touching when they actually are not
not distorted = clavicles lined up and trachea
What are plain films used for? What are the variations? - CORRECT ANSWER - -CXR
-abdomen
-skeletal
variations = fluoroscopy and tomography
What is a fluoroscopy? - CORRECT ANSWER - -uses x-ray tube and fluorescent screen
-real-time motion
-used during procedures!! (heart, abdomen, diaphragm)
-guided placement of GI tubes
What is tomography? When is this most useful? - CORRECT ANSWER - -x-ray tube and
film moved synchronously around focal point
-objects in focal point = focused and everything else blurred
useful: evaluating kidneys, lungs, and bony structures
What are some examples of tomography? - CORRECT ANSWER - 1) CT = computed
tomography
2) PET = Position Emission Tomography
ACTUAL Exam Questions and CORRECT
Answers
Who discovered x-rays? - CORRECT ANSWER - Conrad Roentgen
accidental discovery while investigating emissions from Crookes tube
used almost immediately in medical field
form of electromagnetic radiation energy of extremely short wavelength - CORRECT
ANSWER - x-ray
the shorter the wavelength, the _______ - CORRECT ANSWER - greater its energy and
the greater the ability to penetrate various materials
How are x-rays measured? - CORRECT ANSWER - electron volts
How does x-ray work? - CORRECT ANSWER - 1) produced when an electron beam hits a
metal target
2) beam and target are enclosed in a device called x-ray tube
3) x-ray tube has special window to allow x-rays to escape (controls size of beam)
4) directed at x-ray film that is placed behind the patient
Absorption of x radiation depends on - CORRECT ANSWER - substance's density and
atomic weight
,lower the atomic weight/density, the more transparent it is to x-rays
the degree to which x-rays are absorbed/deflected by the body part - CORRECT
ANSWER - attenuation
The ______ attenuate more radiation than the surrounding tissues - CORRECT
ANSWER - bones
higher density = heavier "shadows" of x-ray film
Dark area on x-ray =
Light area on x-ray = - CORRECT ANSWER - dark = less dense, more x-ray went
through (air)
light = more dense, less x-ray went through (bones, solids)
Radiopaque = - CORRECT ANSWER - more dense, light
ex: bones
Radiolucent = - CORRECT ANSWER - less dense, dark
ex: lungs
What are the four types of radiographic densities? - CORRECT ANSWER - 1) Gas (Air) =
black
2) Fat
3) Water
,4) Bone = white
ex: water = soft tissue
if water in the lungs, will turn the film more white
What factors affect image quality? Which ones should we pay attention to the most as a
clinician? - CORRECT ANSWER - 1) Thickness of the body part
2) Motion
3) Scatter
4) *Magnification*
5) *Distortion*
How does motion effect the x-rays? - CORRECT ANSWER - causes blurring
overcome by: shortening the exposure time, using an intensifying screen that is found in all film
holders
How is scatter produced in x-ray? - CORRECT ANSWER - deflection of some of the
primary x-ray beam
grid is used to reduce scatter
How does magnification effect the x-ray results? - CORRECT ANSWER - as an object
moves toward the x-ray, the shadow becomes larger
-The closer the patient is to the film, the more true to size the organs will be.
-If the patient is further away, it will appear falsely enlarged
, How does distortion occur when taking an x-ray? How do you confirm the x-ray is not distorted?
- CORRECT ANSWER - when the object is NOT perpendicular to the x-ray beam
this makes it appear that two things are touching when they actually are not
not distorted = clavicles lined up and trachea
What are plain films used for? What are the variations? - CORRECT ANSWER - -CXR
-abdomen
-skeletal
variations = fluoroscopy and tomography
What is a fluoroscopy? - CORRECT ANSWER - -uses x-ray tube and fluorescent screen
-real-time motion
-used during procedures!! (heart, abdomen, diaphragm)
-guided placement of GI tubes
What is tomography? When is this most useful? - CORRECT ANSWER - -x-ray tube and
film moved synchronously around focal point
-objects in focal point = focused and everything else blurred
useful: evaluating kidneys, lungs, and bony structures
What are some examples of tomography? - CORRECT ANSWER - 1) CT = computed
tomography
2) PET = Position Emission Tomography
