Correction of phasefront aberrations and pulse reverberations in medical ultrasound imaging

A method for corrections of phasefront aberrations and pulse reverberations in medical ultrasound imaging, where

• ultrasound beams on transmit and/or receive are formed with an ultrasound transducer array that has a two-dimensional distribution of elements, a maximal linear dimension of the elements being smaller than a spatial correlation length of the phase amplitude seen across the array surface,
• a individual array element signals are filtered in a correction filter before standard beam forming is done, both for the transmit and/or the receive beams,
• the correction filters are estimated by
• introducing into a soft tissue image field one or more artificial ultrasound point scatterers,
• receiving backscatterd signal from the point scatterers with the transducer array,
• the point scatterers being spaced apart that the signals from the individual scatterers can clearly be discriminated from each other,
• the signals from the point scatterers having characteristics in amplitude or frequency content, or both, so that they are clearly separable from the tissue signal,
• the signals from the individual point scatterers being used to derive correction filters to correct for phase aberrations and pulse reverberations both in the receive and the transmit beams.