Physics Mod 3

Question 1

Scanned vs non-scanned modalities

Answer 1

1) Scanned acquire over plane/volume; nonscanned acquire along a line
2) temporal resolution degraded with scanned modalities
3) non-scanned modalities has higher risk of thermal bioeffects

Question 2

Time it takes for an individual beam to image soft tissue through 1 cm of imaging depth

Answer 2

13 micro seconds

Question 3

Formats of transducers

Answer 3

1) sector
2) linear (unsteered)
3) linear (steered)
4) linear (trapezoidal)
5) curved linear

Question 4

Calculating pulse repetition period

Answer 4

Depth (cm) x 13 micro seconds/cm

Question 5

Calculating pulse repetition frequency

Answer 5

Reciprocal of PRP

Typical range +/- 10 kHz

Question 6

Frame time calculation

Answer 6

Time it takes to create a single frame or scan

Frame time = time/line x lines/frame = 13 microsec/cm x depth/line x line/frame

Question 7

Modality with worst temporal resolution

Answer 7

color doppler