Thursday, March 13, 1997
4:30-5:30 pm
1003 EECS
Abstract -
The inability of diagnostic ultrasound to detect low contrast lesions
deep inside the body has limited its success in cancer diagnosis. One
of the major problems limiting contrast resolution is sound velocity
inhomogenieties within the body. For example, in abdominal imaging,
differences in index of refraction between
tissue and subcutaneous fatty layers can distort propagating wavefronts,
resulting in reduced contrast in the image. As a result, low-contrast
objects
cannot be visualized. In addition, artifacts may be introduced into the
image. To correct for these aberrations and restore image
contrast, we have developed the Parallel Adaptive Receive Compensation
Algorithm (PARCA). PARCA models the effects of aberrations as off-axis
scatterers insonified by an imperfect beam. Image artifacts created by
these
scatterers can then be estimated and compensated. Results from
controlled aberration models with tissue mimicking gelatin phantoms
as well as clinical abdominal images demonstrate that PARCA can
significantly
improve images degraded by aberrations.
Biosketch -
Please refer to Mr. Krishnan's homepage
found through the link shown above.