Optimizing Spectral Doppler
LOGIQ 7 Online Help 5-89
Direction 2392536-100 Rev. 1
Optimizing Spectral Doppler
Intended Use
Doppler is intended to provide measurement data concerning
the velocity of moving tissues and fluids. PW Doppler lets you
examine blood flow data selectively from a small region called
the sample volume.
Typical Use - PW Doppler
In Pulsed Wave Doppler (PW) Mode, energy is transmitted from
the ultrasound probe into the patient, as in B-Mode. However,
the received echoes are processed to extract the difference in
frequency between the transmitted and received signals.
Differences in frequencies can be caused by moving objects in
the path of the ultrasound signal, such as moving blood cells.
The resultant signals are presented audibly through the system
speakers and graphically on the system display. The X axis of
the graph represents time while the Y axis represents the shift in
frequency. The Y axis can also be calibrated to represent
velocity in either a forward or reverse direction.
PW Doppler is typically used for displaying the speed, direction,
and spectral content of blood flow at selected anatomical sites.
PW Doppler operates in two different modes: conventional PW
and High Pulse Repetition Frequency (HPRF).
PW Doppler can be combined with B-Mode for rapidly selecting
the anatomical site for PW Doppler examination. The site where
PW Doppler data is derived appears graphically on the B-Mode
image (Sample Volume Gate). The sample volume gate can be
moved anywhere within the B-Mode image.
To Next Page
Loading...
Need help?
General
