Which statement describes the purpose of using a spectral Doppler wall filter?

Which statement describes the purpose of using a spectral Doppler wall filter?
A . To widen the area in which the Doppler shift is sampled
B . To clean up the audio signals
C . To eliminate the higher velocity signals
D . To eliminate the lower velocity signals

View Answer

Answer: D

Explanation:

The purpose of using a spectral Doppler wall filter is to eliminate lower velocity signals. Wall filters are designed to remove low-frequency Doppler shifts caused by the motion of the vessel walls or surrounding tissues, which are generally of no diagnostic value. By eliminating these lower velocity signals, the wall filter helps to clean up the Doppler signal and reduce clutter, allowing for a clearer and more accurate display of blood flow velocities.

Reference: ARDMS Sonography Principles and Instrumentation (SPI) Exam Study Guide "Diagnostic Ultrasound: Principles and Instruments" by Frederick W. Kremkau