URR SPI section

Question 1

do sound waves carry matter or particles along the waveform? what do they carry?

Answer 1

no matter or particles are carried; they carry energy from one point to another

Question 2

amplitude of reflected wave is proportional to these two things

Answer 2

incident angle and acoustic impedance mismatch

Question 3

different transducers: single element requires electronic or mechanical 1) focusing 2) steering

Answer 3

requires mechanical focusing and mechanical steering

Question 4

transducer frequency is inversely proportional to

Answer 4

penetration - high frequency probes have reduced penetration and improved spatial and contrast resolution

Question 5

scatter increases or decreases with increasing frequency

Answer 5

increases… directly proportional

Question 6

what three things are inversely proportional to transmitted frequency?

Answer 6

beam width, spatial pulse length, and pulse duration… increase the transmit frequency and these parameters decrease

Question 7

whats the average transducer frequencies

Answer 7

2.5 - 4 MHz

Question 8

A thin easy to image patient would be what frequency transdx

Answer 8

5 MHz

Question 9

A large patient or a patient with lung dz/COPD would use what frequency transdx

Answer 9

2MHz

Question 10

different transducers: sector phased array requires electronic or mechanical 1) focusing 2) steering

Answer 10

electronic both… used for echo, abdominal, pelvic, vascular, transcranial, neonatal brain imaging

greater field of view in far field the linear image… most limited field of view in near field compared to all transdx types

PIE SHAPE

Question 11

Vector array what shape, used for, and electronic or mechanical focusing/steering

Answer 11

trapezoidal; both electronic steering and focusing… can be used for echo, abdominal, pelvic, vascular, transcranial, neonatal brain imaging too