1Gulsah Yildirim, 1Hakkı Muammer Karakas

1University of Health Sciences, Istanbul Fatih Sultan Mehmet Training and Research Hospital, Department of Radiology1, Istanbul, Turkey


Treatment of benign thyroid nodules may be performed due to compressive symptoms, cosmetic problems, malignant transformation risk, and/or anxiety. In recent years, minimally invasive percutaneous ablation methods are increasingly used instead of surgical treatment. Microwave ablation (MWA) is the new approach for thermal ablation of thyroid nodules, though data on uncooled MWA is rather limited. This study aims to investigate the safety and short-term effectiveness of percutaneous uncooled MWA in the treatment of benign thyroid nodules.

Material(s) and Method(s):

The largest diameter, volume, and composition of the nodules were evaluated before the procedure and at 3-month follow up. Uncooled MWA system with 18G probe was used for the procedure. Thyroid function monitorization and antibody tests, clinical compressive symptoms and cosmetic scores were evaluated before the procedure and at 3-month follow up. Volume reduction rates were also evaluated at 3-month follow-up.


A total of 12 nodules, consisting of 8 solid and 4 mostly solid nodules were treated. Major, minor complications were not observed. The mean largest diameter was 41.64±11.41 mm and mean volume was 20.93±14.82 cm3 before the procedure, while the mean largest diameter was 28.6±5.97 mm and mean volume was 8.19±3.30 cm3 at 3-month follow-up. There was a statistically significant difference between diameter (p=0.011) and volumes (p=0.015) before and after the procedure. The volume reduction rate at 3 months was 50.20±39.58%. Before the procedure, median cosmetic score was 4 and symptom score was 6; at 3-month follow-up these scores were 2 and 1, respectively (Figure 1, 2). There was no significant change in thyroid function tests and antibody levels at follow-up (Table 1).


In conclusion, uncooled MWA system using 18G probe was found to be a safe and effective method in the treatment of benign thyroid nodules. With its advantages of rapidly improving clinical symptomatology and cosmetic complaints without requiring hospitalization, it has the potential to be more preferred than surgery by patients