In is very important to get an even temperature distribution through the target tissue for effective hyperthermia treatment. But many factors affect temperature distribution and some degree of temperature inhomogeneity is unavoidable in clinical
situation. One of the most important factors is cooling effect of blood flow in target tissue.
In this study, to evaluate the magnitude and extent of vascular cooling effect, phantoms with tubes of various diameters were designed with or without blood flow through the tube.
@ES The results are as follows.
@EN 1) The temperature was lowered significantly near the surface of the tubes by blood flow and this cooling effect decreased exponentially as the distance from the tube was increased.
2) As the diameter of tube increased, the magnitude and extent of cooling effect increased.
Temperature drop at tube surface and extent of vascular cooling were 2.8℃ and 3cm, 3.0℃ and 4cm, 3.2℃ and 4cm, and 4.0℃ and 4.5cm with tubes of inner diameter of 2.25mm, 4mm, 6mm, and 8mm, respectively.
3) Clinically significant cooling effect of more than 0.5℃ was present within 1.5cm, 2.0cm, 2.0cm, and 2.5cm, from the tubes with inner diameters of 2.25mm, 4mm, 6mm, and 8mm, respectively.
4) Flow rate affected the temperature decrease minimally.
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