Pre-processing occurs at which stage in ultrasound image formation?

Pre-processing occurs at which stage in ultrasound image formation?

• A. when the patient is scanned
• B. when images are transferred to the VCR
• C. after the images are on the tape
• D. when the image exits the scan converter

Answer: (A)

Pre-processing happens during data acquisition, as the echoes are being received while the patient is scanned. At this stage the system applies receiver gain and depth-based compensation (time-gain compensation), filtering, and other corrections to the raw signals so they’re ready to form an image. This occurs before the data is converted into an image by the scan converter and long before any storage or post-processing steps. Transferring images to a VCR, recording on tape, or processing after the scan converter are all later stages and not pre-processing.

Pre-processing happens during data acquisition, as the echoes are being received while the patient is scanned. At this stage the system applies receiver gain and depth-based compensation (time-gain compensation), filtering, and other corrections to the raw signals so they’re ready to form an image. This occurs before the data is converted into an image by the scan converter and long before any storage or post-processing steps. Transferring images to a VCR, recording on tape, or processing after the scan converter are all later stages and not pre-processing.