Which two controls are described as adjusting the brightness of the gray-scale area over which color Doppler writes?

Which two controls are described as adjusting the brightness of the gray-scale area over which color Doppler writes?

• A. Threshold and Priority control
• B. Gain and PRF
• C. Wall filter and Threshold
• D. Angle correct and Threshold

Answer: (A)

The two controls are threshold and priority. Threshold sets the minimum Doppler signal needed to display color, which determines how much of the image gets color overlaid. Lowering the threshold expands the colored area and can reduce the visible grayscale brightness there, while raising it narrows the color region and lets more grayscale show through. Priority controls which image dominates in overlap—if color takes priority, the grayscale background is more likely to be obscured where color is written, changing the perceived brightness of the gray-scale area under the color. Together, these two controls define how bright or visible the grayscale area remains where color Doppler is overlaid.

The two controls are threshold and priority. Threshold sets the minimum Doppler signal needed to display color, which determines how much of the image gets color overlaid. Lowering the threshold expands the colored area and can reduce the visible grayscale brightness there, while raising it narrows the color region and lets more grayscale show through. Priority controls which image dominates in overlap—if color takes priority, the grayscale background is more likely to be obscured where color is written, changing the perceived brightness of the gray-scale area under the color. Together, these two controls define how bright or visible the grayscale area remains where color Doppler is overlaid.