Novel approaches to angular scatter imaging using the translating apertures algorithm
A new method of acquiring and processing angular scatter data in ultrasonic imaging is presented. This method, based on the translating apertures algorithm, eliminates system-dependent changes in the received point spread function (psf) that are associated with more conventional methods of angular scatter measurement. This ensures that changes in the received echo are dominated by changes in the angular scattering behavior of insonified targets, and allows for the development of a variety of new imaging methods. Comparison of received echoes acquired at multiple interrogation angles serves to enhance the contrast of targets exhibiting variations in angular scattering behavior relative to the surrounding medium. Emphasis is placed on the improved ability to highlight biological targets that exhibit significant variations in compressibility or density relative to background tissue (e.g. breast microcalcifications, calcified atherosclerotic plaques). Simulation indicates the enhancement of breast microcalcification contrast by 10-30 dB over standard b-mode acquisition at 10 MHz. More sophisticated imaging methods involving the frequency dependence of angular scatter and angular speckle coherence are also discussed. Practical implementation and evaluation of this method on a modern imaging system is discussed, and expectations for the performance and utility of this algorithm in clinical diagnosis are investigated.