Affiliations: [a] Section of Neuroradiology, Department of Radiology, Geneva University Hospital, Geneva, Switzerland | [b] Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan | Department of Bioengineering and Robotics, Graduate School of Engineering, Tohoku University, 6-1-1 Aoba, Aramaki, Aoba, Sendai 980-8579, Japan
Correspondence:
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Address for correspondence: Makoto Ohta, Section of Neuroradiology, Department of Radiology and Medical Informatics, Geneva University Hospital, 24 rue Micheli-du-Crest, CH-1211 Geneva 14, Switzerland. Tel.: +41 22 372 70 30; Fax: +41 22 372 70 72; E-mail: ota@fmail.ifs.tohoku.ac.jp.
Abstract: This paper describes the development of a Polyvinyl alcohol hydrogel (PVA-H) model for calibration and measurement of temperature using image contrast on MRI using DMSO/H2O as a solvent to alter the freezing and melting points of PVA-H. Tissues exposed to temperature changes above 41°C or below 0°C exhibit increasingly extensive and irreversible damage, depending on the exposure duration. MR images can provide a map of temperature if there is sufficient tissue signal. To evaluate treatment principles using temperature changes (hyperthermia, cryotherapy), a model simulating tissue may be useful to provide a reproducible test environment. PVA-H is water soluble and can be seen on MRI. It can be used to construct complicated shapes such as vascular structure, soft tissues, and so on. Therefore, PVA-H can be useful to measure temperatures and assume the distribution of temperature under treatment. In this paper, we applied PVA-H as a temperature detector and calibrated temperature from image contrast. The results exhibit good capability as a temperature detector not only of high temperature (around 41°C), but also of low temperature (as low as −23°C).
