Percutaneous microwave ablatin of benign thyroid nodules Functional imaging in comparison to nodular volume reduction at a 3-month follow-up

摘要

Aim: Thyroid nodules represent a common clinical issue. Amongst other minimally invasive procedures, percutaneous microwave ablation (MWA) poses a promising new approach. The goal of this retrospective study is to find out if there is a correlation between volume reduction after 3 months and Tc-99m-uptake reduction of treated thyroid nodules. Patients, methods: 14 patients with 18 nodules were treated with MWA. Pre-ablative assessment included sonographical and functional imaging of the thyroid with Tc-99m-pertechnetate and Tc-99m-MIBI. Additionally, patients underwent thyroid scintigraphy 24 hours after ablation in order to evaluate the impact of the treatment on a functional level and to ensure sufficient ablation of the targeted area. At a 3-month follow-up, ultrasound examination was performed to assess nodular volume reduction. Results: Mean relative nodular volume reduction after three months was 55.4 +/- 17.9% (p < 0.05). Tc-99m-uptake 24 hours after treatment was 45.2 +/- 31.9% (Tc-99m-MIBI) and 35.7 +/- 20.3% (Tc-99m-pertechnetate) lower than prior to ablation (p < 0.05). Correlating reduction of volume and Tc-99m-uptake, Pearson's r was 0.41 (p < 0.05) for nodules imaged with Tc-99m-MIBI and -0.98 (p < 0.05) for Tc-99m-pertechnetate. According to scintigraphy 99.6 +/- 22.6% of the determined target area could be successfully ablated. Conclusions: MWA can be considered as an efficient, low-risk and convenient new approach to the treatment of benign thyroid nodules. Furthermore, scintigraphy seems to serve as a potential prognostic tool for the later morphological outcome, allowing rapid evaluation of the targeted area in post-ablative examination.