Two Dimensional Imaging

Question 1

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

These transducers steer the beam with a motor and focus the beam with an acoustic lens or a curved PZT element.

Answer 1

c. mechanical transducer

Question 2

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

These transducer systems typically produce an image that, throughout its entire depth, is approximately as wide as the ultrasound transducer itself.

Answer 2

a. linear switched (also called linear sequential) array transducer

Question 3

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

Ultrasound systems using these transducers do not actually steer the ultrasound beams to create a two-dimensional image.

Answer 3

a. linear switched (also called linear sequential) array transducer

e. convex or curvilinear array transducer

Question 4

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

A special sector shape is produced when this transducer is used. It looks like a wedge or a slice of pie, but it doesn’t originate at a point. The sector has a blunted, curved shape at the top. The arc at the top of the image may be a few centimeters wide.

Answer 4

e. convex or curvilinear array transducer

Question 5

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

With these transducers, a sector (wedge-shaped or “slice of pie”) image is produced. At the top, the sector is very narrow and tapers to a point.

Answer 5

b. linear phased array transducer

c. mechanical transducer

d. annular phased array transducer

Question 6

Indicate which of the transducer types are appropriate answers (more than one answer may be correct).

a. linear switched (also called linear sequential) array transducer
b. linear phased array transducer
c. mechanical transducer
d. annular phased array transducer
e. convex or curvilinear array transducer
f. vector array transducer

With these transducers, a trapezoidal image shape is produced. The image is flat at the top and becomes progressively wider at increasing depths.

Answer 6

f. vector array transducer

Question 7

When looking at images produced by these transducer systems, which one can be distinguished from all the others?

a. linear phased array
b. linear switched array
c. annular phased array
d. mechanical transducer

Answer 7

b. linear switched array

Question 8

What is the advantage of using a 1 1/2 dimensional array transducer?

a. improved elevational resolution
b. improved lateral resolution
c. improved axial resolution
d. improved temporal resolution

Answer 8

a. improved elevational resolution

Question 9

Which transducer possesses the best slice thickness resolution?

a. linear phased arrays
b. 2-D arrays
c. 1 1/2 dimensional arrays
d. linear sequential arrays

Answer 9

c. 1 1/2 dimensional arrays

Question 10

What is the use of a greater number of channels to receive echoes from ever increasing depths called?

a. dynamic aperture
b. apodization
c. dynamic frequency tuning
d. subdicing

Answer 10

a. dynamic aperture

Question 11

The excitation of array elements with dissimilar voltages is called ______ and is used to ________.

a. dynamic aperture, reduce refraction
b. subdicing, eliminate lobes
c. apodization, remove flash artifact
d. apodization, reduce lobe artifact

Answer 11

d. apodization, reduce lobe artifact