title: Localized Thyroid Tissue Ablation by High Intensity Focused Ultrasound: Volume Reduction, Effects on Thyroid Function and Immune Response.
abstract: OBJECTIVE
  The aim of this study was to assess the effectiveness of high intensity focused ultrasound (HIFU) in reducing thyroid nodule volume while preserving thyroid function as measured by immunological response.
  
  
  METHODS
  12 patients (9 females) whose average age was 56.9 years (37 - 81) were treated with HIFU in an ambulatory setting. All patients had a single benign thyroid nodule treated in one HIFU session. The median nodular outline volume (NOV) was 3.4  ml (range 0.6 - 5.0  ml). The therapeutic ultrasound probe (Echopulse(®) THC900 888-H) used works with a frequency of 3  MHz, reaching temperatures of 80 - 90° C and a mean output between 87.6 and 192.8  W. To assess possible effects of HIFU on thyroid function, serum levels of triiodothyronine (T3), thyroxine (T4), thyrotropin (TSH), thyroglobulin (hTg) and antibodies against thyroglobulin (TAbs), thyrotropin receptors (TRAbs) and thyroid peroxidase (TPOAbs) were measured at enrollment, 24-hours post-HIFU treatment and at 3-month follow-up.Pre- post thyroglobulin reduction was measured to evaluate the success of ablation and the nodular outline volume (NOV) was evaluated at baseline and the 3-month follow-up to assess effectiveness.
  
  
  RESULTS
  All measured hormone levels were within normal ranges and remained stable (p > 0.05). No clinically meaningful immune reaction was induced (p > 0.05). Thyroglobulin serum levels increased significantly at 24 hours after ablation (p < 0.05) and decreased significantly at the 3-month follow-up (p < 0.05), returning to pre-ablative levels. The median reduction in nodular outline volume (NOV) was 55 % (p < 0.05).
  
  
  CONCLUSIONS
  HIFU is a safe and effective alternative for treating benign thyroid nodules, while preserving thyroid function. Further investigations with multiple treatments should be conducted to evaluate whether additional treatments can achieve greater volume reduction.
authors.affiliation: German Center for Thermoablation of Thyroid Nodules, University Hospital, Frankfurt am Main, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Korkusuz
authors.affiliation: Department of Nuclear Medicine, University Hospital, Frankfurt am Main, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Sennert
authors.affiliation: Department of Nuclear Medicine, University Hospital, Frankfurt am Main, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Fehre
authors.affiliation: German Center for Thermoablation of Thyroid Nodules, University Hospital, Frankfurt am Main, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Happel
authors.affiliation: German Center for Thermoablation of Thyroid Nodules, University Hospital, Frankfurt am Main, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Grünwald
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care / Q000379:methods*; D001323:Autoantibodies / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D057086:High-Intensity Focused Ultrasound Ablation / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011989:Receptors, Thyrotropin / Q000276:immunology; D013954:Thyroglobulin / Q000097:blood; D013960:Thyroid Function Tests; D013963:Thyroid Hormones / Q000097:blood*; D016606:Thyroid Nodule / Q000097:blood* / Q000628:therapy*
chemical_list: D001323:Autoantibodies; D011989:Receptors, Thyrotropin; D013963:Thyroid Hormones; C006606:anti-thyroglobulin; C056626:thyroid microsomal antibodies; D013954:Thyroglobulin