Lecture 2 Flashcards
PW spectral doppler
- sends and receives with the same crystal
- listens at one gate
- produces a spectral waveform
- FFT
color doppler imaging
- Sends and receives with same crystals
- listens at many gates
- measures mean velocities and variance
auto correlation
pw measures
peak systolic
mean velocities
range of velocities
color doppler measures
mean velocities
variance
laminar flow velocities
mean and peak are close
turbulent velocities
mean different velocities are present
pulse train
burst of pulses
PRP
time from beginning of one pulse to the beginning of the next
PRF
number of pulses in one second
pulse packet
of pulse trains used to interrogate a color line of sight
the larger the packet size…
the better quality flow data that is obtained but the slower the frame rate
pulse packet time determines….
the length of time required for sampling
dwell time
the duration of sampling along each line of sight
you must limit the size of the of the
color box in order to obtain adequate color flow
temporal resolution
ability to visualize moving structures
what affects temporal resolution
frame rate
line dinesity
depth
spatial resolution
ability of scanner to depict small structures
is the vessel is dipping to the right…
steer the box to the right
