MON-465 - Periprocedural Efficiency of 7-Mm Versus 10-Mm Active Tips in Thyroid RFA

Radiofrequency ablation (RFA) is an effective treatment for benign thyroid nodules. The procedure utilizes an internally cooled electrode with varying active tip lengths to deliver thermal energy, resulting in coagulative necrosis. Our previous study demonstrated superior volume reduction rates with 7-mm tips compared to 10-mm tips; however, concerns were raised regarding a potential increase in procedure duration with the former. This study evaluates procedural efficiency by comparing the total procedure duration of 7-mm versus 10-mm tips.
We conducted a retrospective chart review of adult patients who underwent RFA by a single endocrinologist at a US-based academic institution from December 2021 to September 2025. We identified 50 patients with confirmed benign thyroid nodules, 88% female, with a mean age of 50.8±16.2 years. Patients were stratified by initial nodule volume ( < 10mL: n=18, 36%; ≥10mL: n=32, 64%) and by tip length used during the procedure (7mm: n=37, 74%; 10mm: n=13, 26%). Using nursing documentation, we analyzed pre-procedure, procedure, and post-procedure durations. Pre-procedure time included patient preparation; procedure time encompassed lidocaine administration, needle positioning, and ablation; post-procedure time measured recovery before discharge.
Procedure duration was found to be significantly longer for ≥10mL nodules regardless of tip size (p < 0.001). For nodules < 10mL, no significant differences were noted between 7-mm and 10-mm tips in pre-procedure (41.5 vs 40.0 minutes, p=0.514), procedure (33.5 vs 37.5 minutes, p=0.545), or post-procedure (41.0 vs 36.5 minutes, p=0.367) durations. Similarly, for nodules ≥10mL, pre-procedure (43.8 vs 48.3 minutes, p=0.373) and procedure (51.8 vs 55.1 minutes, p=0.607) durations were comparable between the two tip sizes. However, 10-mm tips demonstrated a significantly longer post-procedure duration (35.8 vs 46.7 minutes, p=0.013) in larger nodules.
Our findings demonstrate that 7-mm active tips do not increase procedural time compared to 10-mm active tips. We theorize that substantial procedural time is devoted to needle positioning, local anesthesia, and hydrodissection, as needed. Once the needle is correctly placed, ablation proceeds efficiently with either tip length. In fact, the significantly prolonged post-procedure recovery time with 10-mm tips in larger nodules may reflect increased thermal energy delivery during the procedure, causing greater discomfort. Combined with our previous findings of superior volume-reduction rate and lower energy requirements, these results support 7-mm tips as the preferred option for RFA of benign thyroid nodules across all size categories, without compromising procedural efficiency.

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