Lecture Notes: Ultrasound Display Modes

Introduction

Graph Basics:
- Y-axis: vertical line
- X-axis: horizontal line
- Z-axis: depth line (3D world)
Ultrasound Display Modes:
- Interpret and display ultrasound info
- Each mode has a distinct purpose
- Three main types: Amplitude mode (A-mode), Brightness mode (B-mode), Motion mode (M-mode)

Definition: Displays a graph with a spiked appearance representing the amplitude (strength) of returning echo.
Interpretation:
- Tall spikes: strong reflectors
- Short spikes: weak reflectors
- No spikes: no reflector (anechoic)
Visualization:
- Dot travels across screen, jumps for strong echoes
- Flat for no echoes
- Bright white: strong reflectors, Gray: weak reflectors, Black: non-reflectors
Common Usage: Used in ophthalmology for eye examinations
Graph Resemblance: City skyline; x-axis shows time of flight (depth), y-axis shows amplitude

Definition: Gray scale mode, used for diagnostic images
Structure:
- Image made up of scan lines (tiny dots = pixels)
- Original B-mode: Pixels on (white) or off (black)
- Current B-mode: Variety of blacks, whites, grays
Graph Representation:
- X-axis: Depth from the transducer
- Z-axis: Brightness displayed, amplitude shown on oscilloscope
Memorization: X is depth, Z is brightness

Definition: Graphs motion of anatomy over time, useful in cardiac applications
Usage: Used in cardiac, obstetrics for fetal heart, emergency medicine for lung motion
Functionality:
- Uses one scan line
- Motion mapped over time (sample rate = PRF)
Interpretation:
- Horizontal squiggly line: Motion
- Horizontal straight line: No motion
- Top of graph: Shallow echoes, Bottom: Deeper structures
Correlation:
- B-mode image often accompanies M-mode for structure correlation

A-Mode:
- Y-axis: Amplitude, X-axis: Depth
B-Mode:
- X-axis: Depth, Z-axis: Brightness/Amplitude
M-Mode:
- Y-axis: Depth, X-axis: Time
Practice: Go through workbook activities and open-ended questions for self-assessment.