User's Manual

Acclarix AX3 Series Diagnostic Ultrasound System User Manual Measurements and Reports
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5. Move the caliper to the ED point.
Presses of the <Update> key will toggle between active calipers, allowing you to re-position
the PS point or ED point.
6. Press the <Set> key to fix the ED point and complete RI measurement.
TEI: The TEI index measurement is useful for the assessment of ventricular systolic and diastolic
function. Higher TEI index indicates decreased ventricular function.
To use the TEI measurement:
1. Invoke the Measure Function on a Doppler strip.
2. Select TEI from the touch screen.
3. Measure Time A (Mitral Valve Close-Open Duration ) by caliper pairs.
4. Measure Time B (Ventricular Ejection Time) by caliper pairs.
5. The system calculates the TEI index automatically. The illustration is shown below:
dp/dt: The left ventricular dp/dt measurement is a useful index for evaluating myocardial contractility.
To use the dp/dt measurement:
1. Invoke the Measure Function on a Doppler strip.
2. Select dp/dt from the touch screen.
3. Move the caliper to the position at the 100 cm/s scale on one of the cardiac cycles and press
the <Set> key.
4. Move the caliper to the position at 300 cm/s scale on the same cardiac cycle and press the
<Set> key. The time difference " dt " between the two positions come out .
5. The system calculates dp/dt based on the "dt " value . Formula:
dp/dt = 32/dt (mmHg/s)