Image Quality Flashcards
No useful input/ undiagnostic information on the image that will interfere with the visibility of the anatomy is called
Noise
The ability to demonstrate/distinguish a small object in a high contrast image, its accuracy and clarity, is the definition of which of the following?
Spatial resolution
The _________ the SID the _________ the magnification.
greater; smaller
Spatial resolution is affected by which of the following?
focal spot size
Sharply recorded details are demonstrated when:
1. motion is controlled
2. a large focal spot is used
3. a large OID is used
1 only
Shape distortion is controlled by
Alignment
Examinations of body parts with large inherent OID use _________ whenever possible.
large SID
Any unwanted marks on a film are classified as
Artifacts
An increase in OID will cause an increase in:
Magnification
A radiograph showing a relative lack of focal spot blur would be called:
Sharp in detail
When an X-ray beam is filtered, photon quantity in the primary beam would be:
decreased
The formula for magnification factor is:
SID/SOD
A measurement between the source of the X-rays ( in the primary beam) and the image or IR is known as:
SID
To obtain minimum magnification, a technologist should:
position the object close to the IR
A foreshortened image results from:
an inclined object
Any misrepresentation of an anatomic structure that alters its size and / or shape defines:
distortion
Smaller focal spot size causes:
Less blur
The greatest enemy of the sharpness of detail is:
Motion
To avoid shape distortion, which of the following must be paid close attention to?
Part angulation
What radiographic quality factor would be most affected by an excessive amount of geometric blur (focal spot blur)?
Recorded detail
When proper radiographic detail cannot be obtained because of excessive OID, what change in technique may be use to improve the detail?
Increasing SID
Which of the following directly affects the degree of shape distortion in an image
1. object thickness and shape
2. angle of the object in relation to the film
3. OID
4. angle of the beam in relation to the object
5. centering of the x-ray beam to the object
1, 2, 4, and 5
Which of the following would not be included in the principal geometric factors affecting radiographic quality?
-collimation
-distortion
-magnification
-focal spot size
collimation
Which set of conditions will produce an image with the greatest magnification?
Short SID, long OID
Which would provide the greatest detail in an x-ray image?
(1) Small focal spot
(2) Longer SID
1 and 2
With all other factors unchanged, if focal spot size is decreased, image magnification will:
Not change
With all other factors unchanged, if mAs is decreased, image magnification will:
Not change
If the CR is off-centered to an object but there is still alignment with the anatomy/IR and CR, magnification will:
Not change
With all other factors unchanged, if the anatomy of interest is tilted in relation to the IR (and the IR remains parallel with the table/Bucky), image distortion will:
Increase
T/F: Foreshortening and elongation are examples of shape distortion
True
T/F: Recorded detail is a degree of sharpness on the radiograph.
True
T/F: To acquire greater detail you should use a small focal spot.
True
T/F: Typically, there is always slight magnification on radiographic images.
True
T/F: You can increase detail by increasing OID.
False
The smaller the effective focal spot the _______ the recorded detail.
greater
