Chapter 1 Kremkau Flashcards
uses a computer to change sound waves into different colors. These colors show the speed and direction of blood flow in real time
color doppler display
an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other. The effect causes the sudden change in pitch noticeable.
doppler effect
a two-dimensional image in which the organs and tissues of interest are depicted as points of variable brightness
gray-scale image
high-frequency sound waves to view inside the body. Reproduction, representation, or imitation of the physical form of a person or object.
image
(linear scan); referring to the linear array transducer that is used to produce it
linear image
positional information is determined by knowledge of the direction of the pulse when it enters the patient and by measurement of the time it takes for each echo to return to the transducer. The proper location to present the echo can then be determined from a starting point on the display (usually at the top). With knowledge of the sound, the instrument uses the echo arrival time to determine the depth of the structure that produced that echo.
Operating Principle 1
sends several pulses of ultrasound through the cross-section of anatomy to be imaged but does not produce a one-for-one correspondence of pulse and displayed scan line, instead, all the echo information from throughout the anatomic cross-section is collected, and then massive computation processes determine the location and strength of each echo produced at each location in the anatomy.
operating principle 2
pulses of ultrasound generated by a transducer are sent into the patient where they produce echoes at organ boundaries and within biological tissues. These echoes return to the transducer, where they are detected and presented on the display of a sonographic instrument.
pulse-echo technique
one line of echo information, specifically an echo line, data line, or ____ line.
scan line
sector scan, has a shape similar to a slice of pie
sector image
the use of ultrasound in medical anatomic and flow imaging
sonography
quantatative analysis. includes anatomic imaging to determine the location(s) from which the spectral information is acquired
spectral-doppler display
(also called a probe), an instrument (also called a system)
transducer
sound or other vibrations having an ultrasonic frequency. Uses sound waves to create an image
ultrasound
requires scanning the ultrasound through many adjacent 2D tissue cross-sections to form a 3D volume of echo information
Volume Imaging
Sonography is accomplished with a ________ technique.
pulse-echo
sonographic images are composed of many ______.
scan lines
The ________ is a change in frequency caused by moving objects.
Doppler effect
Doppler information is presented in _______, __________, and _________ forms.
audible
color-Doppler
spectral-Doppler
Doppler ultrasound uses
detection
quantatization
evaluation of tissue motion
blood flow by using the Doppler effect
the visible counterpart of an invisible object, produced in an electronic instrument by interaction with the object
ultrasound image
The echoes from one pulse appears as ______.
one scan line
rectangular display
linear image
shape similar to a slice of pie
sector image
A 2d sonographic scan format is commonly limited to three types:
linear
sector
combination
The diagnostic ultrasound imaging (sonography) method has two parts:
Send ______ of ______ into the body, and using ______ received from the anatomy to produce a(n) ______ of that anatomy.
pulses
ultrasound
echoes
image
Ultrasound gray-scale scans are _______-________ images of tissues cross-sections and volumes
pulse-echo
The brightness of an echo, as presented on the display, represents the ______ of the echo.
strength
A linear scan is composed of many _______, ________ scan lines.
vertical, parallel
A sector scan is composed of many scan lines with a common ______.
origin
A sector scan can have a(n) _______ or a _______ at the top.
pointed
curved
Transducers generate ultrasound _______ and receive returning ______.
pulses
echoes
Echo information in 3D is presented on _____ displays.
2D
The Doppler effect is a change in echo _____.
frequency
The motion that produces the Doppler effect is that of the _______.
reflector
Color-Doppler displays can present Doppler - _______ and Doppler - ________ information in color.
shift
power
Diagnostic ultrasound transducers generate a _____ of sound into the body.
pulse
The location of each dot corresponds to the ______ of the echo to return.
time
The method by which each pulse originate from the same starting point is called a ______ image.
sector
Echoes produced by ______ objects have different _______ than pulses sent into the body.
moving
frequencies
