Digitally Encoded Ultrasound with Application to Tissue Harmonic Imaging

One of the fundamental challenges in ultrasound imaging is tissue attenuation, which often limits image resolution and/or penetration, and causes waveform distortion. In state-of-the-art scanners, transmit pulses are usually designed to achieve good image uniformity that strikes a balance between resolution and penetration. These image quality limits have now been pushed to new levels through a GE-proprietary Digitally Encoded Ultrasound (DEU) technology on the LOGIQ 700 leadership systems.

DEU encompasses digital encoding/decoding techniques which represent new dimensions in digital waveform design and signal processing that can significantly improve imaging of a highly attenuating medium like body tissue.

The Digitally Encoded Ultrasound Platform

A digital ultrasound system refers to one which employs a digital transmitter and receiver to form the transmit and receive ultrasound beams, respectively (as shown in the figure below). The rest of the image processing is also done digitally.

Summary

• Digitally Encoded Ultrasound (DEU) is a revolutionary digital beamforming technology that harnesses advanced digital encoding and decoding techniques on transmit and receive respectively.

• The use of coded pulse sequences provides two general benefits : increased sensitivity to weak echoes, and suppression of unwanted echo components; these are key to such advanced applications as Coded Excitation, B-Flow, Coded Harmonics and Coded Harmonic Angio (contrast agent imaging).

• In Coded Harmonics, a receive decoder, rather than frequently filter, is used to suppress unwanted fundamental frequency components, thereby provide high frequency and wideband tissue harmonic imaging.

• The advanced DEU platform of LOGIQ 700 EXPERT Series system comprises a highly programmable encoder/ decoder which can generate and decipher long, coded pulse sequences.