Prefusion is the principal determinant of temperature distribution of tissue by the cooling effect of blood flow on hyperthermia. So, the effect of tissue perfusion on hyperthermia may be one of the most important factor in the response of
tumors.
In this study, to evaluate the cooling effect of tissue perfusion, dynamic phantom was heated with 915 MHz microwave and the temperature distrbution was observed.
1) The temperature decreased slowly upto the depth of 1.5 cm from the phantom surface, but beyond that, it decreased rapidly. And beyond 3.5 cm, temperature of 42.5℃for effective hyperthermia conld never be achieved with any power and any flow
rate.
2) Under a constant microwave power, temperature rise was inversely proportional to the flow rate, but when the flow rate was extremely slow or fast, the relation could not hold.
3) Under a constant flow rate, temperature rise was proportional to the microwave power, and inversely proportional to the flow rate.
4) From the results, we could estimate the microwave power required for effective hyperthermia along the flow rate and depth.
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