Which statement correctly describes the relationship between depth of view and PRP?

Which statement correctly describes the relationship between depth of view and PRP?

• A. PRP decreases with depth of view
• B. PRP increases with depth of view
• C. PRP is unaffected by depth of view
• D. PRP varies randomly with depth of view

Answer: (B)

PRP is the time between successive ultrasound pulses. It increases with depth of view because deeper imaging requires the sound wave to travel farther and back before the next pulse is emitted. The deeper the deepest point being imaged, the longer the round-trip travel time, so the system must extend the interval between pulses. A common way to think about it is PRP ≈ 2 × depth / speed of sound in tissue (about 1540 m/s). As depth grows, PRP grows, which also lowers frame rate since more time is spent waiting for echoes from greater depths. The other ideas—PRP decreasing, staying the same, or varying randomly with depth—don’t align with this straightforward travel-time relationship.

PRP is the time between successive ultrasound pulses. It increases with depth of view because deeper imaging requires the sound wave to travel farther and back before the next pulse is emitted. The deeper the deepest point being imaged, the longer the round-trip travel time, so the system must extend the interval between pulses. A common way to think about it is PRP ≈ 2 × depth / speed of sound in tissue (about 1540 m/s). As depth grows, PRP grows, which also lowers frame rate since more time is spent waiting for echoes from greater depths. The other ideas—PRP decreasing, staying the same, or varying randomly with depth—don’t align with this straightforward travel-time relationship.