Advance Knobology for B-Mode Imaging - Frequency - Bandwidth
Frequency - Bandwidth
Bandwidth:
the RANGE of frequencies a probe is capable of emitting which you can indirectly control via:
- Pulse length: resolution
- Attenuation: improve echo return
To appreciate what happens to an image when the frequencies are changed, the images below show two sets of images: cervical vessels and right upper quadrant. Each region is scanned by PEN, GEN, and RES.
See any differences? Not much really, but sometimes, the differences can be quite stark.
How about this set of images taken at PEN, GEN, and RES settings with a linear probe? Notice any difference?
There appears a be much differences comparing the PEN vs RES mode. In RES, the structures are better defined relative to PEN which is more grainy.
Take Home Messages:
- Each probe has a range of frequency - bandwidth - that you may select from
- As acquire images through the range of frequencies offered by a transducer, the final image produced on screen may alter significantly or not so
- View the image from different parts of the bandwidth to see what offers you the optimal image