Chapter 4 Flashcards
A- Mode
Mode of operation in which the display presents echo amplitude versus depth
Amplification
The process by which small voltages are increased to larger ones
Amplifier
A device that accomplishes amplification
Analog
Related to a procedure or system in which data are represented in proportional continuously variable physical quantities
Analog to Digital Converter
A device that converts voltage amplitude to a number
B-Mode
Mode of operation in which the display presents a spot of appropriate brightness for each echo received by the transducer
B Scan
A B-mode image that represents an anatomic cross section through the scanning plane
Bandpass filter
An electronic device or circuit that allows signals between two specific frequencies to pass, but that discriminates against signals at other frequencies
Beam Former
The part of an instrument that accomplishes electronic beam scanning, apodization, steering, focusing and aperture with arrays
Bistable
Having 2 possible states
Bit
Binary digit
Channel
A single 1 or 2 way path for transmitting electric signals, in distinction of other parallel paths.
Cine Loop
Sequential display of all the frames stored in memory at a controllable frame rate
Coded Excitation
A sophisticated form of transmission in which the driving voltage pulses have intrapulse variations in amplitude, frequency, and or phase
Compensation
Equalization of received echo amplitude differences caused by different attenuations for different reflector depths
Compression
Reduction indifference in small and large amplitudes
Contrast Resolution
Ability of a gray scale display to distinguish between echoes of slightly different intensities
Demodulation
Detection
Depth Gain Compensation
See Compensation
Detection
Conversion of voltage pulses from radio frequency to to video form
Digital
Procedure or system in which data are represented in numeric value
Digital to Analog Converter
A device that converts a number to a proportional voltage amplitude
Display
A device that presents a visual image derived from voltages received from an image processor
Dynamic Range
Ratio of largest to smallest power that a system can handle
Elastography
Imaging tissue stiffness by tracking movement under mechanical stress
Flat Panel Display
A back-lighted rectangular matrix of thousands of crystal display elements
Frame
A single image produced by 1 complete scan of the sound beam
Frame Rate
of frames of echo info stored each second
Freeze Frame
Constant display of one of the frames in memory
Gain
Ratio of amplifier output to input electric power
Gray Scale
Range of brightness between white and black
Image Memory
The part of the image processor where echo information is stored in image format
Image Processor
An electronic device that manipulates and prepares images for visual presentation
Lateral Gain Control
Gain controls that enable different gain values to be applied laterally across an image to compensate for different attenuation values in anatomic regions
M-Mode
A B-mode presentation of changing reflector position versus time
Panoramic Imaging
The extension of the field of view beyond the normal limits of a transducer scan plane
Persistence
Averaging sequential frames together
PACS
The system provides means or electronically communicating images and associated information to work stations and devices external to the ultrasound instrument.
Pixel
Picture element
Post Processing
Image processing done after storage in the memory
Pre Processing
Signal and image processing accomplished before storage in memory
Radio Frequency
Voltages representing echoes in cyclic form
Real Time
Imaging with a rapid frame sequence display
Real Time Display
A display that appears to image moving structures or a changing scan plane continuously
Refresh Rate
The number of times each second that info is sent from the image memory to the display
Scan Line
A line produced on a display that represents ultrasonic echoes returning from the body
Scanning
The sweeping of a sound beam through the anatomy to produce an image
