Ultrasound Basics Step 5 Step 5 (1 hour) Complete the Self Learning Pre-Tests Modes & Probes - Dopler Self Test 1. What is Doppler ultrasound used for? Measure cardiac dimensions over time Addition to 2D echo by filtering artifacts Addition to 2D echo by harmonic Detect presence, speed, and direction of blood flow Based on Doppler principle, when a sound source moves away from an observer, the frequency will: Decrease Increase Stay the same Cannot be determined A positive Doppler shift means: Red blood cells are moving towards probe Red blood cells are moving away from probe Red blood cells are not moving Doppler information is most accurate when angle of ultrasound beam and moving object is: Perpendicular Parallel Any angle T or F: On color flow, arterial blood is always red and venous is always blue. True False