Physics Evaluation and Quality Control of Hyperthermia Equipment
A typical configuration of modern hyperthermia equipment used in clinics for localized cancer treatment is shown in Fig. 3.1. It can be described as a closed loop system in that the energy deposited into tissues is controlled by a feedback mechanism depending on the temperature of one or more reference probes. The applicator in this system is designed to deposit electromagnetic or ultrasonic energy into tissues which, when absorbed, is converted into heat and raises the temperature of the tumor. The overall goal is to elevate the temperature of the entire tumor to above 42°C while maintaining the hot spots in normal tissues at below 46°C for periods of up to 1 h. Two to ten treatment sessions over a period of 6 weeks may be required for complete therapy. Clinical experience to date has shown that even this seemingly modest goal is difficult to achieve in a reliable and reproducible manner. The reasons for this are manifold. First, there is a lack of standard equipment to deposit energy in a controlled manner and generate optimum heating patterns in specific tumor sites.
KeywordsCoupling Efficiency Physic Evaluation Specific Absorption Rate Heating Pattern Hyperthermia Treatment
Unable to display preview. Download preview PDF.
- Christensen DA (1983) Thermometry and thermography. In: Storm FK (ed) Hyperthermia in cancer therapy. Hall Medical, Boston, pp 223–232Google Scholar
- Curley MG, Lele PP (1984) Some potential errors in measurement of temperatures in vivo during hyperthermia by ultrasound and electromagnetic energy. In: Overgaard J (ed) Hyperthermia oncology 1984, vol 1. Summary papers, proceedings of the 4th int symposium on hyperthermia oncology, Aarhus, Denmark, 2–6 July 1984. Taylor and Francis, London, pp 561–654Google Scholar
- Fessenden P, Lee ER, Samulski TV (1984) Direct temperature measurements. Cancer Res 4 (Suppl): 4799–4804Google Scholar
- Lee ER, Fessenden P (1984) Evaluation of parylene insulated, flexible multiple junction thermocouple temperature probes for ultrasound hyperthermia. Proceedings of the 5th annual meeting, North American Hyperthermia Group, OrlandoGoogle Scholar
- Saylor TK, Shrivastava PN, Paliwal BR (1984) Performance and QA tests for thermometers used in hyperthermia (abstract). Radiation Research Society Abstracts, 16. Academic, San DiegoGoogle Scholar
- Saylor TK, Matloubieh AY, Shrivastava PN (1988) Quality assurance for thermometry. In: Paliwal B, Hetzel F, Dewirst M (eds) Biological, physical and clinical aspects of hyperthermia. AAPM Monograph 16. American Institute of Physics, New York NY, pp 380–395Google Scholar