A COMPARISON OF ACOUSTIC CAVITATION DETECTION THRESHOLDS MEASURED WITH PIEZO-ELECTRIC AND FIBER-OPTIC HYDROPHONE SENSORS

作者：Bull Victoria^*; Civale John; Rivens Ian; ter Haar Gail

来源：Ultrasound in Medicine and Biology, 2013, 39(12): 2406-2421.

DOI：10.1016/j.ultrasmedbio.2013.06.010

• Passive cavitation detection
• High-intensity focused ultrasound
• Focused ultrasound surgery
• Fiber-optic hydrophone
• Cavitation thresholds

A Fabry-Perot interferometer fiber-optic hydrophone (FOH) was investigated for use as an acoustic cavitation detector and compared with a piezo-ceramic passive cavitation detector (PCD). Both detectors were used to measure negative pressure thresholds for broadband emissions in 3% agar and ex vivo bovine liver simultaneously. FOH-detected half-and fourth-harmonic emissions were also studied. Three thresholds were defined and investigated: (i) onset of cavitation; (ii) 100% probability of cavitation; and (iii) a time-integrated threshold where broadband signals integrated over a 3-s exposure duration, averaged over 5-10 repeat exposures, become statistically significantly greater than noise. The statistical sensitiviy of FOH broadband detection was low compared with that of the PCD (0.43/0.31 in agar/liver). FOH-detected fourth-harmonic data agreed best with PCD broadband (sensitivity: 0.95/0.94, specificity: 0.89/0.76 in agar/liver). The FOH has potential as a cavitation detector, particularly in applications where space is limited or during magnetic resonance-guided studies. (E-mail: victoriabull1@googlemail.

• 出版日期2013-12