

Type of Document Master's Thesis Author Smith, Sandra Kay Author's Email Address sasmith1@vt.edu URN etd-05142004-110908 Title Theoretical Feasibility Study of Preferential Hyperthermia Using Silicon Carbide Inserts Degree Master of Science Department Mechanical Engineering Advisory Committee
Advisor Name Title Scott, Elaine P. Committee Chair Clark, David E. Committee Member Thomas, James R. Jr. Committee Member Keywords
- thermal dose
- hyperthemia modeling
- preferential hyperthermia
Date of Defense 2004-04-30 Availability unrestricted Abstract Recently, hyperthermia has been investigated as an alternate therapy for thetreatment of tumors. The present project explored the feasibility of preferential
hyperthermia as a method of treating deep seated tumors. The overall goal of this
research was to determine theoretically if preferential heating could be used to attain the
desired thermal dose (DTD) for a two cm diameter tumor.
The simulations in this work show that, when using a single silicon carbide insert,
the model cannot provide enough energy for an entire 2 cm diameter tumor to receive the
DTD. However, when using an enhanced design model with multiple (4) silicon carbide
inserts, the DTD could be attained in a tumor up to 3.5 cm in diameter.
This study involved using the commercially available software package ANSYS
7.0 program to model a spherical 2 cm tumor, assuming the tumor is located in deep
tissue with a constant perfusion rate and no major blood vessels nearby. This tumor was
placed in the center of a cube of healthy tissue. To achieve the preferential heating of the
tumor, a silicon carbide insert was placed in the center of the tumor and microwave
energy was applied to the insert (in the form of volumetric heating). The thermal
modeling of this system was based on the Pennes Bioheat equation with a maximum
temperature limitation of 80 ºC. The Thermal Dose Analyzer software program was used
to evaluate the results of the thermal simulations (from ANSYS) to determine if the DTD
had been attained.
Additional enhanced design models were also examined. These models include 2
cm and 4 cm tumors with four silicon carbide inserts symmetrically placed about the
tumor and a 4 cm tumor model using a single silicon carbide insert with antennae
attached to the insert to increase energy distribution to the tumor. The simulations show
that only the enhanced design cases with four silicon carbide inserts can achieve the DTD
for an entire 2 cm tumor.
Files
Filename Size Approximate Download Time (Hours:Minutes:Seconds)
28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access Thesis.pdf 2.26 Mb 00:10:28 00:05:23 00:04:42 00:02:21 00:00:12
If you have questions or technical problems, please Contact DLA.