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PubMed · 1510885

Non-invasive thermometry with multi-frequency microwave radiometry.

S Mizushina·T Shimizu·T Sugiura
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Abstract

The present status of the development of a non-invasive thermometer based on microwave radiometry at our laboratory is reported. We have developed a model fitting technique combined with a Monte Carlo technique to retrieve temperature-depth profiles from multi (4-6)-frequency-band microwave radiometric data along with confidence intervals (2-sigma) of tissue temperatures as a function of depth. In order to make the radiometric technique compatible with the heating, brightness temperatures are measured through a 1 cm thick water bolus. Results of phantom experiments are presented to demonstrate the above capabilities of the method. Numerical simulation studies have shown that 2-sigma intervals would be 1.0 K or less over a 0-4 cm range and 1.4 K at 5 cm from the surface with using a six-band, 1-5 GHz radiometer having brightness temperature resolution of 0.03 K (3 s integration time). The six-band instrument is currently being assembled at our laboratory.

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Body TemperatureBreast NeoplasmsFemaleHumansHyperthermia, InducedMathematicsMicrowavesModels, BiologicalMonitoring, PhysiologicMonte Carlo MethodThermometersJournal Article

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S Mizushina, T Shimizu, T Sugiura. 1992. Non-invasive thermometry with multi-frequency microwave radiometry.. https://pubmed.ncbi.nlm.nih.gov/1510885/

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