Ultrasound Modes

1. B-mode (Bright)

This is the standard mode that produces a 2D grayscale image
It displays structures based on their echogenicity

2. M-mode (Motion)

This displays motion over time along a selected line from the B-mode image. It appears as a waveform tracing of movement over time.
It is commonly used during lung assessments to evaluate heart valves, lung sliding, IVC

3. Colour Doppler

This overlays colour on B-mode to show the direction and velocity of blood flow. It detects motion by measuring frequency shifts in returning sound waves as they reflect off moving blood.
For best results, the probe should be angled less than 90° to the direction of flow (ideally lined up)
Recall BART (Blue Away, Red Toward)
- Red: flow toward probe
- Blue: flow away from the probe

4. Pulse Wave Doppler

This measures blood flow velocity at a specific point. For accurate readings, keep the angle of insonation (between probe and flow direction) as parallel as possible
On the Doppler tracing, flow toward the probe appears above the baseline; flow away appears below.
Tip: Use angle correction to align the Doppler cursor with the direction of flow.

5. Tissue Wave Doppler (TDI)

This is a type of pulse wave Doppler that measures the movement of tissue instead of blood flow. It's commonly used to assess heart muscle motion (e.g. in diastolic function assessment).

6. Continuous Wave Doppler

This measures high-velocity blood flow along the entire path of the ultrasound beam
It captures movement throughout the whole Doppler line, which means it’s less precise at pinpointing the exact location but it’s great for measuring very fast flow (i.e. aortic stenosis flow).