Papers Published

1. Dahl, J.J. and McAleavey, S.A. and Pinton, G.F. and Soo, M.S. and Trahey, G.E., Adaptive imaging on a diagnostic ultrasound scanner at quasi real-time rates, IEEE Trans. Ultrason. Ferroelectr. Freq. Control (USA), vol. 53 no. 10 (2006), pp. 1832 - 43 .
   (last updated on 2007/04/16)

   Abstract:
   Constructing an ultrasonic imaging system capable of compensating for phase errors in real-time is a significant challenge in adaptive imaging. We present a versatile adaptive imaging system capable of updating arrival time profiles at frame rates of approximately 2 frames per second (fps) with 1-D arrays and up to 0.81 fps for 1.75-D arrays, depending on the desired near-field phase correction algorithm. A novel feature included in this system is the ability to update the aberration profile at multiple beam locations for 1-D arrays. The features of this real-time adaptive imaging system are illustrated in tissue-mimicking phantoms with physical near-field phase screens and evaluated in clinical breast tissue with a 1.75-D array. The contrast-to-noise ratio (CNR) of anechoic cysts was shown to improve dramatically in the tissue-mimicking phantoms. In breast tissue, the width of point-like targets showed significant improvement: a reduction of 26.2% on average. Brightness of these targets, however, marginally decreased by 3.9%. For larger structures such as cysts, little improvement in features and CNR were observed, which is likely a result of the system assuming an infinite isoplariatic patch size for the 1.75-D arrays. The necessary requirements for constructing a real-time adaptive imaging system are also discussed

   Keywords:
   biological organs;biological tissues;biomedical ultrasonics;brightness;gynaecology;phantoms;