Methods for measuring acoustic power of an ultrasonic neurosurgical device

Scientific paper - Original scientific paper

• Title (croatian): Metode za mjerenje akustičke snage izvora ultrazvuka u neurokirurgiji
• Author: Antonio Petošić
• Author: Bojan Ivančević
• Author: Dragoljub Svilar
• Author: Tihomir Štimac
• Author: Josip Paladino
• Author: Darko Orešković
• Author: Ivana Jurjević
• Author: Marijan Klarica
• Author's institution: University of Zagreb; School of Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences

Abstract (english)

Measurement of the acoustic power in high-energy ultrasonic devices is complex due to occurence of the strong cavitation in front of the sonotrode tip. In our research we used three methods for characterization of our new ultrasonic probe for neuroendoscopic procedures. The first method is based on the electromechanical characterization of the device measuring the displacement of the sonotrode tip and input electrical impedance around excitation frequency with different amounts of the applied electrical power. The second method is based on measuring the spatial pressure magnitude distribution of an ultrasound surgical device produced in an anechoic tank. The acoustic reciprocity principle is used to determinate the derived acoustic power of equivalent ultrasound sources at frequency components present in the spectrum of radiated ultrasonic waves. The third method is based on measuring the total absorbed acoustic power in the restricted volume of water using the calorimetric method. In the electromechanical characterization, calculated electroacoustic efficiency factor from equivalent electrical circuits is between 40–60%, the same as one obtained measuring the derived acoustic power in an anechoic tank when there is no cavitation. When cavitation activity is present in the front of the sonotrode tip the bubble cloud has a significant influence on the derived acoustic power and decreases electroacoustic efficiency. The measured output acoustic power using calorimetric method is greater then derived acoustic power, due to a large amount of heat energy released in the cavitation process.

Abstract (croatian)

Mjerenje akustičke snage visoko-energetskih ultrazvučnih izvora je složeno zbog pojave kavitacije ispred vrha sonotrode. Uobičajeno je koristiti samo jednu metodu za mjerenje izlazne akustičke snage, međutim u ovome istraživanju su primjenjene i uspoređene sve tri preporučene metode vrednovanja ultrazvučnog izvora. Prva metoda se temelji na karakterizaciji pretvarača i sastoji se od mjerenja pomaka sonotrode i ulazne električne impedancije oko pobudne frekvencije s različitim razinama privedene električne snage. Druga metoda se temelji na mjerenju prostorne raspodjele magnitude tlaka ultrazvučnog izvora u »gluhom« bazenu. Princip akustičkog reciprociteta se koristi za određivanje isijane akustičke snage ekvivalentnih izvora na frekvencijskim komponentama prisutnim u spektru ultrazvučnih valova. Treća metoda se temelji na kalorimetrijskom mjerenju apsorbirane akustičke snage u vodi. Elektromehaničkom karakterizacijom sonotrode dobivena je vrijednost elektroakustičkog koeficijenta iskorištenja od 40% do 60% što je približno jednako vrijednosti dobivenoj mjerenjem isijane akustičke snage u »gluhom« bazenu u linearnom načinu rada sonotrode kada nema kavitacije. Kada je prisutna kavitacijska aktivnost ispred vrha sonotrode, nastali oblak mjehurića značajano smanjuje isijanu akustičku snagu. Izlazna akustička snaga dobivena kalorimetrijskom metodom je veća od isijane akustičke snage izmjerene ostalim metodama. U budućim istraživanjima mjereni akustički parametri će se povezati s biološkim učincima u neuralnom i drugim tkivima.

• Keywords (english): Equipment Design; Neurosurgical Procedures / instrumentation; Ultrasonography / instrumentation; Ultrasonography / standards
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Collegium Antropologicum
• Numbering: vol. 35, no. S. 1, pp. 107-113
• p-ISSN: 0350-6134
• URN:NBN: urn:nbn:hr:105:336228
• Publication: 2011-01
• Document URL: https://hrcak.srce.hr/64051
• Type of resource: Text
• Access conditions: Open access
• Created on: 2024-03-28 12:02:33