The cyclic fluctuation of ultrasonic integrated backscatter(IB)of myocardium is regarded as an indicator of myocardial ischemia.It has the potential to be used for the clinical diagnosis of myocardial ischemia.Using high speed data acquisition equipment and commercial B mode ultrasonic equipment,a two dimension IB acquisition system is established.Based on the reconstructed B mode image,the image of myocardium is located and its IB is calculated.To validate the system,animal experiment has been carried ...