Sonography-Guided Ethanol Ablation of a Remnant Solid Component after Radio-Frequency Ablation of Benign Solid Thyroid Nodules: A Preliminary Study

BACKGROUND AND PURPOSE: No study has previously examined the feasibility of using EA to remove any peripherally located, solid components remaining after treatment of benign solid thyroid nodules by RFA. The aim of this study was to assess the efficacy of EA in removing remnant solid components following the incomplete ablation of benign solid thyroid nodules by RFA.

MATERIALS AND METHODS: During a 1-year period, RFA was performed in 18 benign solid thyroid nodules in 17 patients. EA was subsequently performed on 8 of these nodules. The success rate of EA, size and vascularity of the remaining solid components, amount of injected ethanol, degree of intranodular echo staining just after ethanol injection, and number of EA sessions were assessed.

RESULTS: Of 18 post-RFA nodules, 8 nodules were subsequently treated with EA because of incomplete ablation, as defined by the presence of peripherally located vascularized solid components. On follow-up US, 2 nodules showed marked hypoechogenicity and no vascularity of the remaining solid components, while 3 nodules showed considerably decreased echogenicity and vascularity of the remaining solid components. Three nodules showed no significant decrease or mild decrease in the echogenicity and vascularity of the remaining solid components. No serious complications were observed during or after RFA or EA, with the exception of 1 patient who experienced diffuse glandular hemorrhage during these procedures.

CONCLUSIONS: EA was effectively used to remove incompletely ablated components of benign solid thyroid nodules remaining after RFA.