A METHOD FOR ESTIMATING AN OVERLYING LAYER CORRECTION IN QUANTITATIVEULTRASOUND IMAGING

A new method is tested to compensate for attenuation losses through th e intervening layers in quantitative ultrasound imaging. The method su btracts the echo signal power spectrum acquired from a uniform region beneath the overlying layers from the signal power spectrum obtained f rom a reference phantom using the same instrumentation system settings . Changes in spectral components with frequency are then used to estim ate the attenuation of the overlying layers. Several phantoms were use d to test the method, among which was a phantom having three windows, one with no overlying layers and the other two with fat and muscle mim icking layers of different degrees of irregularity. Attenuation losses through the windows were compensated for using the technique, produci ng backscatter estimator images of a simulated tumor inside the phanto m. After applying the method, consistent results for the backscatter e stimator of the tumor, as well as the backscatter coefficient of the b ackground material, were obtained from the various windows. (C) 1995 A cademic Press, Inc.