Patent ID: 8790263

Claim:
A method of locating moving tissue, the method comprising: transmitting a first and second ultrasound pulse at a first sample volume within an object; receiving a first echo signal of the first ultrasound pulse from the first sample volume and a second echo signal of the second ultrasound pulse from the first sample volume; computing by a computing device an estimate of position displacement of the first sample volume from the first and second echo signals, the position displacement being a measure of change of position over time; comparing by the computing device a characteristic of the estimated position displacement to a predetermined position displacement characteristic indicative of an amount of physical position displacement of moving tissue, the amount of physical position displacement of moving tissue being greater than zero, the predetermined position displacement characteristic comprising position displacement corresponding to a vein or position displacement corresponding to an artery; determining by the computing device, based on the comparison, whether the first sample volume corresponds to moving tissue; repeating said transmitting, receiving, computing and determining for a second sample volume, the repeating initiated by the computing device based on the determination for the first sample volume; and identifying by the computing device the moving tissue as being a specific one of the vein or the artery, the identifying distinguishing a vein as opposed to an artery or the artery as opposed to the vein based on the characteristic of the estimated position displacement over time relative to pulsatility.