Abstract:
:Ultrasound in the low megahertz frequency range is used by physiotherapists to treat a variety of conditions. The treatments reduce swelling, reduce pain and increase movement at joints. Ultrasound is now also beginning to be used to treat malignant tumours. The tumours are heated to temperatures between 42 degrees and 45 degrees C, producing cellular damage, the extent of which is determined by the duration and number of treatments and 'concurrent' treatments by chemo and x-ray therapy. In the light of the results of computer simulation, we discuss in this paper: (a) The properties of a five-element divergent transducer array to treat large superficial neoplastic tumours. The field distribution measured by the Sarvazyan method will be described and also compared with that of computer simulation. The benefits of frequency wobbling will also be discussed. (b) The possibility of employing a multiple field applicator for use by physiotherapists to obviate the need for continuous movement of a small transducer of area approximately 5 cm2 over the affected area.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Quan KM,Shiran M,Watmough DJdoi
10.1088/0031-9155/34/11/019subject
Has Abstractpub_date
1989-11-01 00:00:00pages
1719-31issue
11eissn
0031-9155issn
1361-6560journal_volume
34pub_type
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