In B-mode, what does a darker dot indicate compared with a brighter dot?

In B-mode, what does a darker dot indicate compared with a brighter dot?

• A. Darker indicates weaker reflections; brighter indicates stronger
• B. Darker indicates stronger; brighter weaker
• C. Darker indicates depth; brightness indicates speed
• D. Darker indicates noise; brightness indicates nothing

Answer: (A)

In B-mode ultrasound, the brightness of each dot on the screen represents how strong the reflected echo is from a tissue interface. A stronger echo, which comes from interfaces with a larger impedance difference, appears as a brighter dot. A weaker echo appears as a darker dot. Depth is shown by how far the dot is from the top, not by its brightness, and the brightness is not about speed or motion. So a darker dot indicates a weaker reflection, while a brighter dot indicates a stronger reflection.

In B-mode ultrasound, the brightness of each dot on the screen represents how strong the reflected echo is from a tissue interface. A stronger echo, which comes from interfaces with a larger impedance difference, appears as a brighter dot. A weaker echo appears as a darker dot. Depth is shown by how far the dot is from the top, not by its brightness, and the brightness is not about speed or motion. So a darker dot indicates a weaker reflection, while a brighter dot indicates a stronger reflection.