Combining high-intensity focused ultrasound (HIFU) ablation with percutaneous ethanol injection (PEI) in the treatment of benign thyroid nodules

Objective: Assessing the 6-month efficacy of combined high-intensity focused ultrasound (HIFU) ablation with percutaneous ethanol injection (PEI) in benign thyroid nodules by comparing it with HIFU ablation alone.

Methods: One hundred and eighty-one (55.2%) patients underwent HIFU alone (group I) while 147 (44.8%) underwent concomitant HIFU and PEI treatment for solid or predominantly solid nodules (group II). Intravenous sedation and analgesia were given before the start of treatment. Extent of nodule shrinkage (by volume reduction ratio (VRR)), pain scores (by 0-10 visual analogue scale) during and after ablation, and rate of vocal cord palsy (VCP), skin burn, and nausea/vomiting were compared between the two groups.

Results: The mean amount of ethanol injected in group II was 1.3 ± 0.7 ml. The 3- and 6-month VRR were significantly greater in group II (60.41 ± 20.49% vs. 50.13 ± 21.06%, p = 0.001; and 71.08 ± 21.25% vs. 61.37 ± 22.76%, p = 0.001, respectively), and "on-beam" treatment time was significantly shorter in group II (26.55 min vs. 30.26 min, p = 0.001). Group II patients reported significantly lower pain score during treatment (2.24 ± 3.07 vs. 4.97 ± 3.21, p < 0.001) and 2 h after treatment (2.23 ± 2.50 vs. 2.97 ± 4.39, p = 0.044). Rates of VCP, skin burn, and nausea or vomiting were not significantly different (p > 0.05).

Conclusions: The combined HIFU and PEI approach with improved administration of intravenous sedation and analgesia was associated with a significantly better 6-month efficacy than HIFU alone in benign thyroid nodules without compromising the safety and comfort of patients.

Key points: • Concomitant HIFU and PEI have a better treatment efficacy than HIFU alone. • Concomitant HIFU and PEI have a comparable safety profile as HIFU alone.

Keywords: Ablation techniques; High-intensity focused ultrasound ablation; Interventional ultrasonography; Nodular goiter; Ultrasonic imaging.