Abstract
The objective of this study is to demonstrate the cavitation-enhanced heating via combining low-frequency ultrasound during an ultrasound thermal treatment. Two ultrasound transducers were used: A 566-kHz spherical transducer was used to generate the thermal lesion while another 40-kHz planar transducer was positioned orthogonally with its axis across the focus of the high-frequency one. The emission and backscattered signals from the bubble activity were also recorded during the heating process by a needle hydrophone. Compared to the lesion formed by exposure to the focused transducer only, its size increased up to 200% and 140% in the axial direction and cross section, respectively. The enlarged lesion, rather than being in tadpole shape, symmetrically in the focal direction, which implied that the cavitation-enhanced lesions could be generated without losing its penetration ability. This study demonstrates an easy and effective approach to enlarge the final size of a thermal lesion by applying low frequency ultrasound simultaneously, and would be important if a large-volume and deep-sited thermal lesion by ultrasound ablation was necessary.
| Original language | English |
|---|---|
| Pages (from-to) | 1477-1480 |
| Number of pages | 4 |
| Journal | Proceedings - IEEE Ultrasonics Symposium |
| Volume | 2 |
| State | Published - 2004 |
| Externally published | Yes |
| Event | 2004 IEEE Ultrasonics Symposium - Montreal, Que., Canada Duration: 23 08 2004 → 27 08 2004 |