SSI-6000/SSI-5800/SSI-5500/SSI-5500BW
Digital Color Doppler Ultrasound System
5.3.5
Focal Zones
The focal zone determines the depth range for optimizing the concentration of the
ultrasound beam.
Multiple focal zones are possible. The marker ( ) for focal zone is indicated at the
depth scale.
FOCAL NUMBER
To change the number of focal zones:
• go to the B mode menu (
Section 5.3.1
), highlight
FOCAL NUMBER
.
• use the
LEFT/RIGHT
keys to decrease/increase the focal zone numbers.
The focal depth is adjustable during the real time scan regardless
of the imaging mode (B, CDI, PW/CW, . . . ) and display format
(single, dual, quad).
If multiple focal zones are present, they are shifted with the same amount
of depth. To change the depth position(s) of the focal zone(s):
• flip the
FOCUS
switch downwards to shift the focal zones to deeper locations.
• flip the
FOCUS
switch upwards to shift the focal zones to shallower locations.
Remarks:
• The maximum number of focal zones depends on the probe in use.
• Increasing the focal number decreases the frame rate and increases the acous-
tic power indices.
• Increasing the focal zone depth increases the acoustic power indices.
5.3.6
Tissue Acoustic Characteristics
TISSUE ACOUSTIC
The speed of ultrasound depends on the tissue it is passing through. Tissue acous-
tic characteristics specifies the ultrasound speed used for measurements and cal-
culations. Adjust this parameter to fine tune the focusing.
To change the Tissue acoustic characteristics,
• go to the B mode menu (
Section 5.3.1
), highlight
TISSUE ACOUSTIC
.
• use the
LEFT/RIGHT
keys to decrease/increase the tissue acoustic value.
Remarks:
• The calculations that depends on the ultrasound velocity varies with the value
of
TISSUE ACOUSTIC
.
• For your reference, Table 5.1 provides the sound speeds in miscellaneous tis-
sues/organs/materials.
P/N: 4701-0061-01B
5-5
