GE Vivid S60N, Базовое руководство по обслуживанию

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D
IRECTION
FR091521, R
EVISION
1 V
IVID
S60N/V
IVID
S70N B
ASIC
S
ERVICE
M
ANUAL
Chapter 4 - General Procedures and Functional Checks 4-31
P R E L I M I N A R Y
• Use Quick angle and Angle correction to steer the ultrasound beam to the blood flow to be
measured (Not typically required during cardiac studies).
• Adjust LPRF (PW Doppler mode only) to toggle between high and low Pulse Repetition Frequency
(PRF). When the Doppler PRF is raised beyond a certain limit, more than one Doppler gate is
displayed on the screen.
• Press Auto on the Control panel to activate Automatic Spectrum Optimization (ASO). ASO is used
to automatically adjust baseline and scale of the PW/CW spectrum to optimize the spectral display.
It will avoid the display of a folded spectrum and stretch the spectrum vertically as large as possible.
ASO optimization is not continuous but performed instantaneously each time
Auto is pressed.
4-3-7 Tissue Velocity Imaging (TVI) Checks
4-3-7-1 Introduction
TVI calculates and color codes the velocities in tissue. The tissue velocity information is acquired by
sampling of tissue Doppler velocity values at discrete points. The information is stored in a combined
format with grey-scale imaging during one or several cardiac cycles with high temporal resolution.
4-3-7-2 TVI Overview
Figure 4-22 TVI Mode Screen
1. TVI color bar
2. Parameter
window