Thermoablationsverfahren an der Schilddrüse — Vergleich der Laserinduzierten Thermotherapie (LITT) und der Radiofrequenzinduzierten Thermotherapie (RFITT) als neue Therapiesysteme zur lokalen Behandlung von nodulären Schilddrüsenveränderungen

Abstract

Introduction: Because of their minimal invasive access and low complication rate, thermoablative thechniques, increasingly used for the treatment of tumors in parenchymatous organs, are also interesting for patients bearing thyroid gland lesions necessitating surgery. Aim of this study was to evaluate and compare the dose-effect-relations of Laserinduced Thermotherapy (LITT) and Radiofrequencyinduced Thermotherapy (RFITT) in thyroid tissue to demonstrate the necessary parameters for a safe clinical use for the first time and to lay the foundations for a reasoned choice of procedure. Materials and methods: In porcine thyroid glands thermoablation was performed either by LITT or RFITT using power settings between 10 W and 20 W. Temperature spread during application was documented in 5 mm and 10 mm distance of the applicator. Postinterventional lesion diameters were measured and lesion sizes calculated. Results: Lesion volumes ranged between 0,4 ccm and 3 ccm and showed different characteristics in their spread for both techniques. A lesion volume plateau was observed in both techniques. Endtemperatures ranged between 75 °C and 117 °C in 5 mm distance and 52°C and 85°C in 10 mm distance of the applicator. Conclusion: Both techniques allow definitive and reproducible induction of clinical relevant lesions in thyroid tissue. Both methods differ in their respective complexity. Optimal energy doses and application times for a safe ablation in the clinical application of both techniques were documented for the first time.