Advance Knobology for B-Mode Imaging - Time Gain Compensation
Time Gain Compensation
Time Gain Compensation:
The processor increases the amplitude of echoes in accordance to depth (time for the pulse to return) to compensate for attenuation. With TGC, you can control both signal amplification and attenuation from a specific depth.
Think of it like the “Gain”, but with fine control.
Here are two sets of pictures taken with different TGC settings. On the far left are neutral images. In the middle column, the TGC is increased for the center portion of the image (the dial is slided all the way to the right -- max), therefore the center portion of the image appears brighter than the top and bottom 1/3 of the image. The most adjacent set of images shows the TGC for the top 1/3 of the screen has been minimized so the structures look darker where as the bottom 1/3 are amplified to look brighter.
Think of it like the “Gain”, but with fine control.
Here are two sets of pictures taken with different TGC settings. On the far left are neutral images. In the middle column, the TGC is increased for the center portion of the image (the dial is slided all the way to the right -- max), therefore the center portion of the image appears brighter than the top and bottom 1/3 of the image. The most adjacent set of images shows the TGC for the top 1/3 of the screen has been minimized so the structures look darker where as the bottom 1/3 are amplified to look brighter.
Take Home Messages:
- TGC is like Gain but finer control for specific depths