Physics Test Ch. 12 and 13 Flashcards Preview

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Flashcards in Physics Test Ch. 12 and 13 Deck (46)
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1

When the crystals are defective, the entire image is destroyed with this type of transducer

Single crystal transducer. Mechanical transducer Pg 167

2

Which transducer creates a beam that is focused in all planes and at all depths?

annular phased array

3

What is the advantage of using a 1 1/2 dimensional array transducer?

Creates thinner beams with improved slice thickness ( or elevational resolution) over a greater range of depths p 190

4

What type of resolution is improved with a 1 1/2 dimensional array transducer?

Slice thickness and Elevational resolution Pg 188

5

What is the image shape of a vector array transducer?

Trapezoidal Pg 187

6

Which transducer has active elements arranged in a straight line?

Linear Pg 168

7

Which transducer has active elements arranged in circular rings?

Annular Pg 168

8

Which transducer has active elements arranged in an arched or bowed matter?

Convex Pg168

9

Phased array always means what?

Adjustable or multi-focused Pg 170

10

Linear switch transducer has what type of steering technique?

Also called linear sequential. Has electronic steering. Pg 187

11

What type of probe has dropout lines of image information from top to bottom?

Linear and convex Pg 187

12

Horizontal or side to side dropout occurs in which transducer type when crystals are bad?

Annular phased array. Pg187

13

Which transducer is designed to be mechanically steered and fixed with single focus?

Mechanical Pg187

14

The use of more active elements to receive reflections with a greater time of flight is called

Dynamic aperture? *found on a quizlet

15

What is the ultrasound machine that can display real time images and Doppler?

Duplex pg 313

16

The ability to accurately locate moving structures at any time is what kind of resolution?

Temporal resolution Pg 198

17

What will decrease temporal resolution?

Deeper imaging, which decrease frame rate and degrades temporal resolution Pg 200

18

Real-time imaging could be referred to as…?

Ultrasound "movie" Pg 197

19

What determines temporal resolution?

Frame rate Pg 198

20

What are the factors that limit frame rate?

-speed of sound in the medium
-Imaging depth Pg 198

21

What will affect the pulses in a single image?

-Number of focal points
-Sector size
-Line density Pg 201

22

If we double imaging depth, what happens to frame rate?

Frame rate is halved Pg 210

23

Imaging to greater depth of view requires what?

-Long go-return time
-Longer Tframe
-Lower frame rate
-Inferior temporal resolution Pg 200

24

What will degrade temporal resolution?

(Lower frame rate)
-Deeper imaging
-Multiple focal points
-Wide sector
-High line density Pg 209

25

What is the sector size that will use the fewest pulses?

The narrowest sector size p. 204

26

The sonographer increases line density from 1 line to 3 lines, what will be the consequence of this action?

Temporal resolution decreases p. 211

27

If the frame rate is 50 Hz, how long does it take to create a frame?

1/50 sec p. 214 (#23 is an example of this)

28

Lateral resolution improves with what?

Multi-focusing p 209

29

Low line density creates what?

-widely spaced lines
-fewer pulses per frame
-shorter T frame
-higher frame rate
-high temporal resolution
-poor spatial resolution p. 207 (yellow box)

30

What creates an image with poor movie quality but high image quality?

-Poor temporal resolution
-Low frame rate Pg 208