Thyroid Microwave Ablation Study Based on Fiber Bragg Gratings Thermal Mapping

Thyroid nodules represent a widespread health concern and surgery is often adopted even if the incidence of frequent post-operative complications is not negligible. In recent years, this framework has fostered the growing spread of thermal ablation treatments, in particular microwave ablation (MWA). To date, despite its relevance, state-of-the-art regarding temperature monitoring in thyroid tissue during MWA is lacking. In this paper, the effects of MWA in thyroid by monitoring temperatures have been explored. By using several fiber Bragg gratings (FBGs) temperature sensors, the heat maps in the proximity of the MW antenna have been reconstructed for two different power values set at generator. An increase up to about 4.5 cm ³ in ablation volume and up to 24 °C in maximum temperature variation as power rises from 20 W to 30 W has been observed. In addition, the dependency of the temperature evolution on the involved power has been investigated, observing that, with increasing power, some FBGs recorded a ΔT slope increase until the maximum values, resulting in shorter ablation times, and others recorded a plateau phase until the end of the MWA treatment. Such a propensity could be relevant to adjust the clinical settings according to the desired treatment outcome.