Non-linear ultrasound imaging

The recent introduction of non-linear imaging in ultrasound diagnosis could improve image quality by resolving some problems in technically difficult patients allowing a better conspicuity in identification of subtle lesions. Tissue harmonics are generated while the transmitted pulse propagates thro ugh tissue. The formation of image by utilising the harmonic signals implie s the suppression of fundamental frequency in the received signal. This is achieved by two major processes filtering and pulse inversion imaging. The non-linear properties of contrast agents reinforce the intensity of har monic signals which could be detected in precise conditions of acoustic pow er for a non-destructive or destructive imaging. The introduction of this n ew imaging modality opens new way in ultrasound imaging with precise protoc ols of acquisition or sequences and possibly in therapy in the near future.