Title :
Ultrasonic microheaters using piezo-ceramics for cauterization and other applications
Author :
Visvanathan, Karthik ; Gianchandani, Yogesh B.
Author_Institution :
Dept. of Mech. Eng., Univ. of Michigan, Ann Arbor, MI, USA
Abstract :
This paper presents the use of piezoelectric ultrasonic microheaters for cauterization of biological tissues for tumor ablation and hemostasis. Ultrasonic heaters using PZT-5A ceramic of 3.2 mm diameter and 191 mum thickness were used in the experiments. A finite element model was developed to predict the heat generated by these microheaters. The ultrasonic heaters attained maximum temperature and thermal efficiency at frequency corresponding to maximum conductance and maximum impedance respectively. The thermal efficiency at each resonance frequency (0.5-3 MHz) was proportional to effective coupling factor (0.25-0.5) at that mode. The thermal efficiency is 930degC/W for biological tissue. Stacked heaters provide about three times higher efficiency. Branding of porcine tissue using the proposed device is also discussed.
Keywords :
biological tissues; finite element analysis; lead compounds; micromechanical devices; piezoceramics; ultrasonic devices; PZT; PZT-5A ceramic; biological tissues; cauterization; finite element model; frequency 0.5 MHz to 3 MHz; hemostasis; piezo-ceramics; piezoelectric ultrasonic microheaters; porcine tissue branding; size 191 mum; size 3.2 nm; stacked heaters; thermal efficiency; tumor ablation; Biological system modeling; Biological tissues; Ceramics; Finite element methods; Frequency; Impedance; Neoplasms; Predictive models; Temperature; Thermal conductivity; Ultrasonic heating; biological tissue; piezoelectric actuation; thermal elements;
Conference_Titel :
Solid-State Sensors, Actuators and Microsystems Conference, 2009. TRANSDUCERS 2009. International
Conference_Location :
Denver, CO
Print_ISBN :
978-1-4244-4190-7
Electronic_ISBN :
978-1-4244-4193-8
DOI :
10.1109/SENSOR.2009.5285433
