The practical use of thermocouples for temperature measurement in clinical hyperthermia.

The use of thermocouples as invasive thermometers in clinical hyperthermia is comprehensively and critically reviewed. The ability to construct thermocouple probes as small-bore, multiple junction assemblies is a major reason for their popularity and full constructional details are given. The potential sources of measurement error when using thermocouples both in temperature gradients and in electromagnetic or ultrasonic heating fields are discussed. Emphasis is placed upon simple practical solutions to these problems and a combination of good measurement practice and electrical filtering can reduce errors to an insignificant level. Techniques are suggested for the assessment of thermocouple performance during clinical measurement. With careful use, thermocouples can be reliable and convenient thermometers.