Abstract:
:A number of heating sources are available for minimally invasive thermal therapy of tumours. The purpose of this work was to compare, theoretically, the heating characteristics of interstitial microwave, laser and ultrasound sources in three tissue sites: breast, brain and liver. Using a numerical method, the heating patterns, temperature profiles and expected volumes of thermal damage were calculated during standard treatment times with the condition that tissue temperatures were not permitted to rise above 100 degrees C (to ensure tissue vaporization did not occur). Ideal spherical and cylindrical applicators (200 microm and 800 microm radii respectively) were modelled for each energy source to demonstrate the relative importance of geometry and energy attenuation in determining heating and thermal damage profiles. The theoretical model included the effects of the collapse of perfusion due to heating. Heating patterns were less dependent on the energy source when small spherical applicators were modelled than for larger cylindrical applicators due to the very rapid geometrical decrease in energy with distance for the spherical applicators. For larger cylindrical applicators, the energy source was of greater importance. In this case, the energy source with the lowest attenuation coefficient was predicted to produce the largest volume of thermally coagulated tissue, in each tissue site.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Skinner MG,Iizuka MN,Kolios MC,Sherar MDdoi
10.1088/0031-9155/43/12/011subject
Has Abstractpub_date
1998-12-01 00:00:00pages
3535-47issue
12eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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