Abstract: The quality of an ultrasound image is limited by the distortions of the signal transmitted through the body. Ideally the ultrasonic pulse would pass undistorted through the body down until it hits the organ to be imaged. The beam should be reflected by this organ, and then pass undistorted through the body back to the transducer. Sadly this is not possible.
The signal received at the transducer is distorted by multiple reflections, and arrival time and amplitude fluctuations caused by variable tissue parameters. The former is known as reverberations, and the latter phase and amplitude aberrations. The resolution of an ultrasound image is thus limited by these factors. Experimental studies indicate that this aberration significantly reduces the image resolution.
In an effort to gain greater insight into the mechanisms which dominate phase and amplitude aberrations, a simulation program has been developed. This talk will give a brief introduction to the wave equation governing the ultrasound propagation. Simplifications made in order to get an efficient numerical solution based on operator splitting will be discussed. Some numerical experiments will also be presented.