Ch 15 Q & A Flashcards
Which electronic compnenet is required for gray scale imaging?
a. VCR
b. non-interlaced display
c. computer memory
d. scan convertor
d
Which of the following scan converters will provide the best spatial resolution?
a. 256 x 256 pixels
b. 512 x 512 pixels
c. 128 x 128 pixels
d. 1000 x 1000 pixels
d
Which of these statements regarding a bit of computer memory is false?
a. it is the smallest element of an image
b. it is bistable
c. eight bits combine to make a bye
d. it is a component of a digital scan converter
A
How many gray shades can be represented by a group of: 4 bits? 2 bits?
4 bits = 16 shades
2 bits = 4 shades
What is the number of shades that can be represented by 3 bits?
8
2x2x2, 2^3
What is the number of shades that can be represented by 8 bits?
256
2x2x2x2x2x2x2x2,2^8
What is the number of shades that can be represented by 10 bits?
1024
2x2x2x2x2x2x2x2x2x2, 2^10
What is the number of shades that can be represented by n bits?
the number 2 is multiplied by itself
How many bits are needed to store:
10 shades of gray?
11 shades of gray?
15 shades of gray?
Four bits are required to store form 9 to 16 shades of gray
Which of the following statements regarding a pixel is false?
a. it is the smallest part of a digital image
b. a collection of bits, assigned to each pixel, stores the shade of gray
c. it displays up to 3 gray shades simultaneously
d. image quality is improved when the number of pixels is high
C
Are the following procedures usually pre or post processing?
modifying a frozen image
postprocessing
Are the following procedures usually pre or post processing?
read zoom
postprocessing
Are the following procedures usually pre or post processing?
write zoom
preprocessing
Are the following procedures usually pre or post processing?
adjusting the brightness on the monitor
postprocessing
Are the following procedures usually pre or post processing?
increasing the receiver gain
preprocessing
What is the primary disadvantage of video tape and computer disc methods of image archiving?
a. these methods are very costly
b. the info is vulnerable to erasure when exposed to strong magnetic field
c. only low resolution images are stored
d. only black and white images are stored
B
Where does coded excitement take place?
a. transducer
b. receiver
c. pulser
d. PACS system
C
Which of the following is not true about spatial compounding?
a. data is collected from different viewing angles
b. frame rates are reduced
c. shadowing artifact can be eliminated
d. can be performed with a mechanical transducer
D
All of the following are disadvantages of PACS systems except:
a. data will not deteriorate over time
b. images can be delivered to distant locations on the imaging network
c. older, archived studies and reports can be reviewed easily
d. images have higher resolution than what appears on the system’s display
D
What is DICOM?
a. standards for transducer design
b. standards for patient exposure
c. protocols for two- dimensional imaging
d. protocols for medical image data
D
What is the primary storage device on a PACS system?
a. magneto-optical storage
b. hard disc drives
c. solid state memory
d. compact discs
B
Which of the following technologies uses long sound pulses to create an image?
a. coded excitement
b. harmonics
c. pulse inversion
d. rendering
A
With frequency compounding, hw many pulses are transmitted down each scan line?
a, 1
b. 2
c. 4
d. cant be determined
A
Which of the following techniques is used to create image data where none really exists?
a. edge enhancement
b. temporal compounding
c. fill-in interpolation
d. spatial compounding
C
In modern elastography, how are the tissue deformed?
a. by pressing the transducer into skin
b. with the use of a second probe
c. automatically
d. as a result of respiration
C
