A prototype 2-D cylindrical section phased array, as part of an adaptive hyperthermia system, was used to examine the role of implantable acoustic sensors for phase aberration correction and motion compensation in ultrasound hyperthermia. After phase aberration correction and motion compensation, enhanced focal patterns were achieved even in the presence of significant aberration and motion. The limited number of acoustic sensors implanted inside a tumor in the clinic necessitate phase aberrations measured at one point to be extrapolated to other neighboring focal points. According to the results obtained here, significantly improved focal patterns can be obtained if phase aberrations and beam shifts are mainly caused by aberrators close to the array surface and extrapolated focal points are close to measured points.
|Original language||English (US)|
|Title of host publication||1992 Ultrasonics Symposium Proceedings|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|Number of pages||4|
|State||Published - 1992|
|Event||1992 Ultrasonics Symposium - Tucson, United States|
Duration: Oct 20 1992 → Oct 23 1992
|Name||Proceedings - IEEE Ultrasonics Symposium|
|Conference||1992 Ultrasonics Symposium|
|Period||10/20/92 → 10/23/92|
Bibliographical noteFunding Information:
Phase extrapolation is more helpful if the prime distortion is caused by a steering structure (i.e., a wedge or a tilted layer). A simple steering error is common to all foci, making extrapolation nearly ideal. As shown in Fig. 3b, phase extrapolation greatly improved proper relocation of foci steered away by the aberrator. Acknowledgment This work was funded in part by grant CA44124 from the National Institutes of Health and an award from Hitachi Central Research Laboratory, Hitachi, LTD, Tokyo, Japan.
© 1992 IEEE.