Abstract:
:A thermal model for predicting time-dependent temperature distributions during ultrasound heating was tested quantitatively. The relevant thermal processes incorporated in the model are heat conduction and ultrasound power absorption, and the required input parameters include the absolute ultrasound power, the shape and frequency of the ultrasound transducer, and the thermal and acoustical properties of the medium. Testing was done by heating an ultrasonically tissue-mimicking phantom with a 525 kHz, single element, focused source. The phantom has muscle-like acoustical properties and contains an array of copper-constantan thermocouples. Time-dependent temperature changes predicted with the thermal model were in very good agreement with those measured in the phantom, verifying the validity of the model for use in optimizing an ultrasound applicator design for a specific treatment situation.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Chin RB,Zagzebski JA,Madsen ELdoi
10.1088/0031-9155/36/9/001subject
Has Abstractpub_date
1991-09-01 00:00:00pages
1153-64issue
9eissn
0031-9155issn
1361-6560journal_volume
36pub_type
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