Abstract:
:Temperature distributions resulting from hyperthermia treatments on isolated perfused bovine tongues were compared with simulations by a treatment planning system. The aim was to test whether the discrete vessel model used for the treatment planning is able to predict correct generic temperature distributions. Tongues were heated with the multielectrode current source interstitial hyperthermia treatment (MECS IHT) system, while the steady-state temperature distribution was mapped by scanning 10 thermocouples along paths perpendicular to the interstitial implant. For simulations a tongue was defined with generic discrete vasculature and an electrode implant analogue to the experiments. To model vascular generations not described discretely, a local heatsink was implemented at the end of each terminating branch. The discretely modelled vasculature showed itself on the temperature distributions in two ways. Individual vessels caused very local, sharp wells in the tracked temperature profiles. In the presence of large vessels a collective behaviour was also seen, i.e. a regional lowering of temperature. Both phenomena can be recognized in the experimentally obtained temperature distributions too. Predicting correct generic temperature distributions is feasible with the discrete vessel model used.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Raaymakers BW,Crezee J,Lagendijk JJdoi
10.1088/0031-9155/43/5/011subject
Has Abstractpub_date
1998-05-01 00:00:00pages
1199-214issue
5eissn
0031-9155issn
1361-6560journal_volume
43pub_type
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