Which technique would be most helpful in reducing grating lobes in your image?

• A. Beam steering
• B. Tissue harmonic imaging
• C. 3D imaging
• D. Compound imaging

Answer: (B)

Grating lobes are unwanted off-axis energy artifacts from the transducer array that show up as spurious echoes. Tissue harmonic imaging reduces these artifacts by transmitting at a fundamental frequency but listening at the tissue-generated harmonic frequency. The harmonic signal arises mainly in the focal region where pressures are highest, and the system effectively filters out the fundamental. This localization means energy from off-axis directions (where grating lobes would contribute) is greatly diminished, giving cleaner images with better contrast and resolution. Other techniques may influence artifacts or image quality in different ways, but harmonic imaging directly suppresses grating-lobe energy through selective reception of the tissue-generated harmonics.