The efficacy and safety of high-intensity focused ultrasound ablation of benign thyroid nodules

Abstract

High-intensity focused ultrasound (HIFU) is a promising form of thermal ablation of benign thyroid nodules, but evidence supporting its use is scarce. The present review evaluated the efficacy and safety of single-session HIFU treatment of benign thyroid nodules. As reported in the literature, the extent of nodule shrinkage following treatment ranged from 48.8% to 68.8%. Like other forms of ablation, the shrinkage rate was greatest in the first 3-6 months, and the best responders were patients with small (≤10 mL) nodules. Complications were uncommon, but temporary vocal cord palsy occurred in 3%-4% of patients, and was related to the distance between the HIFU beam and the recurrent laryngeal nerve. Despite being safe and efficacious, a larger-scale prospective trial is required.

Keywords: Ablation techniques; Goiter, nodular; High-intensity focused ultrasound ablation; Hyperthermia, induced; Ultrasonography, interventional.

Fig. 1.. A treatment image captured immediately after an 8-second treatment pulse.

The central panel represents the bird-eye view reconstruction of the nodule. The empty circles represent the non-ablated subunits, while the filled circles represent the ablated subunits. The presence of hyperechoic marks (microbubbles) at the focal point of the high-intensity focused ultrasound beams in the treatment screen should also be noted.

Fig. 2.. A 37-year-old woman complaining of a growing right thyroid swelling.

A-C. Sagittal ultrasonography of a right solid thyroid nodule obtained before treatment (A) and 3 months (B) and 6 months (C) after high-intensity focused ultrasound treatment are shown. The extent of nodule shrinkage and the echogenic change (from isoechoic to hypoechoic) after treatment should be noted.