Echo Instrumentation

Question 1

Amplification

Answer 1

Also known as receiver gain or overall gain, which increases amplification at all depths

Question 2

Analog

Answer 2

describes a device or system that represents changing values as continuously variable physical quantities

Question 3

Analog-to-Digital Converter

Answer 3

convert the analog radio frequency (RF) signal to a digital RF signal sampled at a predetermined rate (typical ranges are from 20MHz to 160MHz) and at a predetermined number of bits (typical ranges are from 10 bits to 16 bits)

Question 4

Beam Former

Answer 4

The part of an instrument that accomplishes electric beam scanning, Apodization, steering, focusing, and aperture with arrays

Question 5

Bistable

Answer 5

Having two possible states

Question 6

Bit

Answer 6

Binary digit

Question 7

Cathode-ray tube

Answer 7

A display device that produces an image by scanning an electron beam over a phosphor-coated screen

Question 8

Coded Excitation

Answer 8

extends the bounds of this tradeoff by increasing signal-to-noise ratio (SNR) through appropriate coding on transmit and decoding on receive

Question 9

Compensation

Answer 9

Also known as TGC used to increase amplification at varying depths

Question 10

Compression

Answer 10

Compression decreases the difference between the largest and the smallest voltages or echo amplitudes

Question 11

Contrast Resolution

Answer 11

Ability of a gray scale display to distinguish between echoes of slightly different amplitudes or intensities

Question 12

Demodulation

Answer 12

Conversion of echo voltages from radio frequency (RF) to video form; Also known as detection

Question 13

Depth Gain Compensation

Answer 13

Same as compensation; also called TGC

Question 14

Digital-to-analog converter

Answer 14

(DAC) A device that converts a digital number to a proportional voltage amplitude

Question 15

Dynamic Range

Answer 15

Ratio of the largest to the smallest amplitude or power that a system can handle

Question 16

Frame Rate

Answer 16

the number of sonographic images stored into memory per second

Question 17

Gain

Answer 17

Ratio of amplifier output to input electric power

Question 18

Gray Scale

Answer 18

Range of brightness between white and black

Question 19

Image Memory

Answer 19

After echo data is acquired and converted to proper video format image frames are stored in image memory

Question 20

Image Processor

Answer 20

An electronic device that reformats echo data into image form

Question 21

Persistence

Answer 21

Frame Averaging

Question 22

PACS

Answer 22

Picture archiving and communications systems

Question 23

Pixel

Answer 23

Picture element; the unit into which imaging information is divided for storage and display in a digital instrument

Question 24

Postprocessing

Answer 24

Signal processing done after data emerge from scan converter memory and before display

Question 25

Preprocessing

Answer 25

Image processing done before echo data are stored in image memory

Question 26

Real-time

Answer 26

Imaging with a rapid-frame-sequence display

Question 27

Real-time Display

Answer 27

With a sufficient frame rate, a display that appears to image moving structures or a changing scan plane continuously

Question 28

Scan Converter

Answer 28

Temporarily stores images during scanning, for viewing and recording

Question 29

Signal Processor

Answer 29

picks up amplified signals from the receiver and carries out operations such as filtering, amplitude detection, and signal compression

Question 30

Spatial Compounding

Answer 30

This form of image compounding reduces image noise and speckle, and increases tissue plane definition

Question 31

Temporal resolution

Answer 31

the ability to distinguish closely timed events as separate events; and to correctly display rapidly moving structures

Question 32

Time Gain Compensation

Answer 32

Same as compensation; Also known as DGC