Gain
- Describes the degree of amplification of the reflected signal that is received
- If low gain is used, tissues that are poor reflectors will not be visualised
- If high gain is used noise is added to the image and it can become difficult to delineate different structures
Focus
- The beam possesses a focal point where resolution is highest, much like a camera lens
- This is usually set to an area 2/3rds of the total depth
- The structure of interest should be positioned within the area of greatest focus
Depth
- Optimum depth should always be selected to allow visualisation of the structures without additional areas
- Shallower depth allows for a faster frame rate
Dynamic Range
- Describes the range between the minimum low and maximum high signal intensity that is displayed
- This equates to the contrast that is viewed within the image upon the screen
- Generally a high dynamic range is used to improve the image quality although it may need to be reduced in the presence of "noise"
Sector Width
- Selecting a narrower sector width allows a faster frame rate and increased resolution but with reduced field of view
Frequency
- Can often be changed to increase the resolution depending upon the structures being imaged