High frequency ultrasonic imaging based on a combination of synthetic aperture focusing and limited angle compounding: Small animals imaging results

An imaging system, using mechanically moved high frequency ultrasound (HFUS) transducers (20 MHz and 40MHz), has been realized, which utilizes the synthetic aperture concept for focused HFUS transducers and combines it with limited angle spatial compounding. This combination leads to a high and range independent spatial resolution as well as to speckle reduction and artifact suppression. The system can be applied to investigations which do not require real time operation, for example imaging of soft tissue areas like tumors. Post mortem imaging experiments on small animals (abdomen of young rats, subcutaneous tumors of nude mice) have been carried out.