title: Single-element ultrasound transducer for combined vessel localization and ablation.
abstract: This report describes a system that utilizes a single high-intensity focused ultrasound (HIFU) transducer for both the localization and ablation of arteries with internal diameters of 0.5 and 1.3 mm. In vitro and in vivo tests were performed to demonstrate both the imaging and ablation functionalities of this system. For imaging mode, pulsed acoustic waves (3 cycles for in vitro and 10 cycles for in vivo tests, 2 MPa peak pressure) were emitted from the 2-MHz HIFU transducer, and the backscattered ultrasonic signal was collected by the same transducer to calculate Doppler shifts in the target region. The maximum signal amplitude of the Doppler shift was used to determine the location of the target vessel. The operation mode was then switched to the therapeutic mode and vessel occlusion was successfully produced by high-intensity continuous HIFU waves (12 MPa) for 60 s. The system was then switched back to imaging mode for residual flow to determine the need for a second ablation treatment. The new system might be used to target and occlude unwanted vessels such as vasculature around tumors, and to help with tumor destruction.
authors.affiliation: Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Wen-Shiang
authors.initials: WS
authors.lastname: Chen
authors.forename: Che-Chou
authors.initials: CC
authors.lastname: Shen
authors.forename: Jen-Chieh
authors.initials: JC
authors.lastname: Wang
authors.forename: Chung-Ting
authors.initials: CT
authors.lastname: Ko
authors.forename: Hao-Li
authors.initials: HL
authors.lastname: Liu
authors.forename: Ming-Chih
authors.initials: MC
authors.lastname: Ho
authors.forename: Chiung-Nien
authors.initials: CN
authors.lastname: Chen
authors.forename: Chih-Kuang
authors.initials: CK
authors.lastname: Yeh
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000000981:diagnostic imaging*; D054459:Elasticity Imaging Techniques / Q000295:instrumentation; D004867:Equipment Design; D057086:High-Intensity Focused Ultrasound Ablation / Q000379:methods*; D011817:Rabbits; D051381:Rats; D014159:Transducers; D014464:Ultrasonic Therapy / Q000295:instrumentation* / Q000379:methods; D014465:Ultrasonics / Q000295:instrumentation*; D014656:Vascular Surgical Procedures / Q000295:instrumentation*