What is the relationship between overall gain and image brightness?

What is the relationship between overall gain and image brightness?
A . The higher the overall gain, the brighter the image
B . The lower the overall gain, the brighter the image
C . The higher the overall gain, the darker the image
D . There is no relationship between overall gain and image brightness

View Answer

Answer: A

Explanation:

Overall gain in ultrasound refers to the amplification of all the received echo signals. Increasing the overall gain amplifies the signals, making the entire image brighter. Conversely, decreasing the overall gain reduces the signal amplification, resulting in a darker image. Overall gain adjustment affects the entire image uniformly, unlike time gain compensation (TGC), which adjusts the gain at different depths independently.

Reference: ARDMS Sonography Principles and Instrumentation (SPI) Exam Study Guide "Diagnostic Ultrasound: Principles and Instruments" by Frederick W. Kremkau