When the depth of view is set to 10 cm, PRP is?

When the depth of view is set to 10 cm, PRP is?

• A. 100 μs
• B. 130 μs
• C. 10 μs
• D. 1300 μs

Answer: (B)

PRP is the time between ultrasound pulses, set by the maximum imaging depth. The pulse must travel to the far edge of the depth and back, so the round-trip distance is 2 × depth. For a depth of view of 10 cm, the round-trip distance is 20 cm. Using the speed of sound in soft tissue (~1540 m/s), the travel time is 0.20 m / 1540 m/s ≈ 1.3 × 10^-4 s, which is about 130 μs. Therefore, the correct PRP is 130 μs. Shorter PRP would correspond to a shallower depth, while a much longer PRP would imply a deeper view.

PRP is the time between ultrasound pulses, set by the maximum imaging depth. The pulse must travel to the far edge of the depth and back, so the round-trip distance is 2 × depth. For a depth of view of 10 cm, the round-trip distance is 20 cm. Using the speed of sound in soft tissue (~1540 m/s), the travel time is 0.20 m / 1540 m/s ≈ 1.3 × 10^-4 s, which is about 130 μs. Therefore, the correct PRP is 130 μs. Shorter PRP would correspond to a shallower depth, while a much longer PRP would imply a deeper view.