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Flashcards in Pulse-Echo Deck (31):
0

Increases the strength of all electrical signals in the receiver prior to further processing (receiver gain)

Amplification

1

Relating to or using signals or information represented by a continuously variable physical quantity such as spatial position or voltage.

Analog

2

A signal processing operation where the amplified voltage signal representing an ultrasound echo is converted into a binary number

Analog to digital conversion

3

This introduces a set of time delays across the individual elements

Beam Former

4

This means the system has two stable equilibrium states. Something that is bistable can be resting in either of the two states. These rest stays need not be symmetric with respect to stored energy.

Bistable

5

A display device

Cathode-Ray Tube

6

Creating very long sound pulses containing a wide range of frequencies, distributing energy over a broad frequency range

Coded Excitation

7

This is used to make the image uniformly bright from top to bottom.

Compensation.

8

The phase of the wave when the molecules are pushed together.

Compression

9

The ability of the imaging system to differentiate between body tissues and display them as different shades of gray.

Contrast Resolution

10

Retains the actual amplitudes of echo voltages

Demodulation

11

To allow for greater amplification of the weaker echoes returning from deeper within the body

Depth-Gain Compensation

12

And electronic device for converting digital signals to analog form

Digital to analog converter

13

This allows the range of echoes or shades of gray displayed on the screen to be decreased. This will remove low-level echoes from the display and result in an image with more contrast.

Dynamic Range

14

______ = PRF / Lines per Frame. Depends on the PRF and the number of scan lines per image.

Frame Rate

15

The degree of amplification of the returning echo is called this. Echo or signal amplification is necessary because the returning echoes are too weak to be displayed in visualized. Echoes can be strengthened by increasing the intensity of the transmitted signal or by increasing the amplification of the returning signal.

Gain

16

Allows each echo of varying degrees of amplitude to be displayed within the same image.

Gray scale

17

Stores a number of sequentially acquired and processed static image frames every second which are rapidly sent to the display to provide dynamic real-time ultrasound

Image Memory

18

This formats the many scanline data into form.

Image Processor

19

This is an averaging of sequential frames together to get a smoother image.

Persistence

20

Picture Archiving and Communications System

PACS

21

A minute area of illumination on a display screen; one of many from which an image is composed.

Pixel

22

After the scan converter memory.

Post-Processing

23

Image processing done before echo data is stored in image memory.

Preprocessing.

24

Enable the visualization of moving structures but also helps speed up the examination time.

Real-Time

25

Several images can be presented per second.

Real-Time Display

26

Temporarily stores images during scanning, for viewing and recording. Performs scan conversion, enabling the image data to be viewed on video monitors.

Scan Converter

27

After the images pass through this processor they are fed into the image processor.

Signal Processor

28

Using sonographic info from several different imaging angles to produce a single image and is only available in phased array transducers

Spatial Compounding

29

The ability to accurately portray movement occurring within the field of view during real-time imaging.

Temporal Resolution

30

This is required in order to compensate for the fact that signals returning from deeper reflectors will be weaker than signals returning from more shallow reflectors, because of attenuation. Increasing this amplifies signals more from deeper structures than it does from shallow structures.

Tine-Gain Compensation (TGC)