nov 7

Question 1

Not only must the transducer emit ultrasound pulses and receive echoes, but it must also send the pulses through the many anatomic paths required to generate an image. This sometimes is called

Answer 1

scanning, sweeping, or steering the beam

Question 2

Scanning is done rapidly and automatically so that many images, called ___, can be acquired and presented in rapid sequence within a second

Answer 2

frames

Question 3

Presenting images in a rapid sequential format, similar to a movie, is called

Answer 3

real-time sonography

Question 4

Arrays are operated in two ways, called

Answer 4

sequencing and phasing

Question 5

A more complete name for what is commonly called a linear array is

Answer 5

linear sequenced array

Question 6

size of the group of elements energized to produce each pulse.

Answer 6

aperture

Question 7

also called a curved array, is constructed as a curved line of elements rather than a straight one

Answer 7

convex array

Question 8

operates similarly to the linear array but produces a sector image.

Answer 8

convex array

Question 9

• contains a compact straight line of elements, each about one quarter of a wavelength wide
• operated by applying voltage pulses to most or all elements (not a small group) in the assembly but with small time differences

Answer 9

linear phased array

Question 10

with small (less than 1 μs) time differences (called

Answer 10

phasing

Question 11

phased array is sometimes called an

Answer 11

electronic sector transducer

Question 12

This array contains a straight line of rectangular elements, each approximately one wavelength wide, and is operated by applying voltage pulses to groups of elements in succession.

Answer 12

linear array

Question 13

width of the entire image is approximately ____ to the length of the array

Answer 13

equal

Question 14

pulsing sequence described (____elements, pulsed in groups of ___) yields only ___ scan lines to make up the image. This would certainly be a limited image

Answer 14

8 elementgs, groups of 4, only 5 scan lines

Question 15

A 128-element array pulsed in groups of four would yield a

Answer 15

125-line display.

Question 16

echoes can be generated from a specific anatomic location with several viewing angles. The echo information from these multiple views is processed to present an image of improved quality. This is a form of electronic _____ of an image.

Answer 16

“compounding”