To increase the frame rate while performing an obstetrical sonogram to evaluate the fetal heart, which adjustment is recommended?

To increase the frame rate while performing an obstetrical sonogram to evaluate the fetal heart, which adjustment is recommended?

• A. Increase Focal Zones
• B. Increase Scan Line Density
• C. Decrease Sector Width
• D. Decrease PRF

Answer: (C)

The key idea is temporal resolution in fetal heart imaging: you want as many frames per second as possible to follow rapid cardiac motion. Frame rate in ultrasound is driven by how much of the sector you sweep each frame. Narrowing the sector width reduces the angular sweep, so fewer scan lines are needed per frame. That speeds up data acquisition and increases frame rate, which helps you visualize the beating heart more clearly. Other adjustments trade off frame rate for resolution or Doppler performance. Increasing the number of focal zones or scan line density requires more processing time, lowering the frame rate. Adjusting PRF mainly affects Doppler sampling and velocity measurement, not the base B-mode frame rate. Therefore, decreasing sector width is the best way to boost frame rate for evaluating the fetal heart.

The key idea is temporal resolution in fetal heart imaging: you want as many frames per second as possible to follow rapid cardiac motion. Frame rate in ultrasound is driven by how much of the sector you sweep each frame. Narrowing the sector width reduces the angular sweep, so fewer scan lines are needed per frame. That speeds up data acquisition and increases frame rate, which helps you visualize the beating heart more clearly.

Other adjustments trade off frame rate for resolution or Doppler performance. Increasing the number of focal zones or scan line density requires more processing time, lowering the frame rate. Adjusting PRF mainly affects Doppler sampling and velocity measurement, not the base B-mode frame rate. Therefore, decreasing sector width is the best way to boost frame rate for evaluating the fetal heart.