title: Local thyroid tissue ablation by high-intensity focused ultrasound: effects on thyroid function and first human feasibility study with hot and cold thyroid nodules.
abstract: OBJECTIVE
  The aim of this study was to assess whether high-intensity focused ultrasound (HIFU), a new and promising method for the treatment of benign hot and cold thyroid nodules using thermal ablation, has an impact on thyroid function, and to evaluate its feasibility in outpatient settings. Additionally, a possible difference in the treatment of solid and complex thyroid nodules was evaluated.
  
  
  METHODS
  Ten patients with one thyroid nodule each (six cold and four hot nodules) underwent HIFU in January 2014. Four nodules were solid and six nodules were complex. Serum levels of triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH), thyroglobulin (hTg) and additionally antibodies against hTg (TAK), TSH receptors (TRAK) and thyroid peroxidase (TPO) were measured at enrolment and 24 h after the HIFU treatment. The pre- and post-thyroglobulin reduction was measured to evaluate the scale of ablation. In addition, patients' pain was recorded on a numeric rating scale from 0 to 10.
  
  
  RESULTS
  The HIFU treatment did not affect thyroid function, since hormone levels stayed stable (p < 0.05). No serious immune reaction was induced. Thyroglobulin serum levels increased significantly (p < 0.05) and were correlated to the total energy emitted by HIFU (p < 0.1). The results of complex thyroid nodules did not differ from solid thyroid nodules. Similarly, the results of hot thyroid nodules did not differ from cold thyroid nodules. All patients tolerated the whole treatment and no severe complications were observed.
  
  
  CONCLUSIONS
  HIFU is a safe and effective method to treat benign, solid, complex, hot and cold thyroid nodules preserving thyroid function. Further developments of the system are needed to gain suitability for daily use.
authors.affiliation: Department of Nuclear Medicine, University Hospital Frankfurt , Frankfurt am Main , Germany.
authors.forename: Hüdayi
authors.initials: H
authors.lastname: Korkusuz
authors.forename: Michael
authors.initials: M
authors.lastname: Sennert
authors.forename: Niklas
authors.initials: N
authors.lastname: Fehre
authors.forename: Christian
authors.initials: C
authors.lastname: Happel
authors.forename: Frank
authors.initials: F
authors.lastname: Grünwald
mesh_terms: D005240:Feasibility Studies; D006801:Humans; D013959:Thyroid Diseases / Q000000981:diagnostic imaging*; D013961:Thyroid Gland / Q000000981:diagnostic imaging*; D014463:Ultrasonography
keywords: High-intensity focused ultrasound; thermal ablation; thyroglobulin; thyroid function; thyroid hormones; thyroid nodule