High-intensity focused ultrasound for thyroid nodule ablation: the evidence to date

Abstract

Thyroid nodules are common in occurrence and most of them are benign in nature. Some of these nodules are to be treated as they continue to grow or cause undesirable symptoms. Recently, several minimally invasive thermal ablation techniques have been introduced to overcome the complications of traditional methods such as surgery. High-intensity focused ultrasound (HIFU) is the latest advance in treatment modalities, which is a noninvasive procedure that permits localized target destruction without affecting the surrounding tissues. HIFU is currently used in the treatment of various solid malignant and benign tumors. The purpose of this review is to provide an introduction to the literature, principles, and advances of HIFU therapy of benign thyroid nodules, as well as to provide a discussion on its efficacy, complications, and future.

High-intensity focused ablation (HIFU) of single benign thyroid nodule rarely alters underlying thyroid function

“…HIFU ablation has been shown to be a safe and less-invasive treatment for symptomatic benign thyroid nodules and our reported 6 months efficacy appeared to be consistent with that of the literature [19]. However, despite being a focused treatment with thermal damage confining mostly to the target itself, it is known that the energy in the beam could damage the normal parenchyma on its way to the target area.…”

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

“…Since the recurrent laryngeal nerve runs at the back of the thyroid lobe before entering the larynx, vocal cord palsy (VCP) is a potential complication after HIFU ablation. Indeed, VCP occurred not uncommonly following HIFU treatment in earlier series [ 32 , 33 ]. In a recent series of 103 patients who completed single-session HIFU ablation on one side of the thyroid gland, four patients (3.9%) complained of an immediate voice change after treatment (i.e., on day 0 following treatment) and all were later confirmed to have a completely paralyzed vocal cord by laryngoscopy [ 30 ].…”

Die Echotherapie als nichtinvasives Therapieverfahren von Schilddrüsenveränderungen

“…Beobachtete unerwünschte Ereignisse begrenzen sich bei der Echotherapie auf milde Vorkommnisse und sind in ihrer Natur durchgehend transient [7]. So beobachtete das Team um Lang et al in wenigen Fällen (3 Fälle, 2,8 %) eine transiente, einseitige Stimmbandlähmung, welche sich jedoch innerhalb der ersten 3 Monate nach der Behandlung in allen Fällen vollständig regenerierte [10].…”

“…Umfassend betrachtet zeigten Echotherapie-behandelte Patienten verglichen mit operativen und anderen nicht operativen Methoden damit ein deutlich positiveres Risiken-und Nebenwirkungsprofil [7].…”

“…Dabei werden hochenergetische Ultraschallwellen auf einen Punkt im Gewebe fokussiert, wodurch die Temperatur im Fokuspunkt bis auf 85°C ansteigt und dadurch eine lokale Gewebsnekrose verursacht [2,6]. Nachfolgend kommt es zum Gewebsabbau im Zielgewebe und zu einer Verringerung des behandelten Knotenvolumens [7].…”