title: High-intensity focused ultrasound to treat primary hyperparathyroidism: a feasibility study in four patients.
abstract: OBJECTIVE
  Many patients with primary hyperparathyroidism either decline or are not candidates for surgical parathyroidectomy. There are drawbacks to medical therapy as well as percutaneous ethanol injection as alternative therapies for primary hyperparathyroidism. Therefore, in this pilot study, our aim was to test the feasibility, safety, and efficacy of a newly developed noninvasive high-intensity focused ultrasound (HIFU) technique for the nonsurgical management of primary hyperparathyroidism.
  
  
  METHODS
  We treated four menopausal women with biochemical, sonographic, and cytologic evidence of benign primary hyperparathyroidism. HIFU treatment was performed in two sessions using TH-One under sonographic guidance and with the patient under conscious sedation. Parathyroid volume and function were evaluated at baseline and repeatedly until 12 months after the second HIFU session.
  
  
  RESULTS
  Serum parathyroid hormone levels decreased in all four patients and normalized 1 and 8 months after the second HIFU session in two patients. Serum calcium levels decreased in all patients and normalized in three patients. Three of four parathyroid tumors had decreased in size by 11%, 43%, and 79%, respectively, 12 months after the second HIFU session. All adverse events related to HIFU were transient: mild subcutaneous edema in three patients and impaired vocal cord mobility in one patient that resolved 40 days later.
  
  
  CONCLUSIONS
  HIFU is a promising procedure for patients with primary hyperparathyroidism that may become an alternative to established options, especially in elderly patients with comorbidities, or in patients who decline surgery. Large-scale long-term studies including patients with secondary and tertiary hyperparathyroidism are warranted.
authors.affiliation: Department of Thyroid and Bone Mineral Diseases, Clinical Center of Endocrinology, Sofia Medical University, 1431 Sofia, Bulgaria. roussanka_kov@yahoo.com
authors.forename: Roussanka D
authors.initials: RD
authors.lastname: Kovatcheva
authors.forename: Jordan D
authors.initials: JD
authors.lastname: Vlahov
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Shinkov
authors.forename: Anna-Maria
authors.initials: AM
authors.lastname: Borissova
authors.forename: Joo Ha
authors.initials: JH
authors.lastname: Hwang
authors.forename: Françoise
authors.initials: F
authors.lastname: Arnaud
authors.forename: Laszlo
authors.initials: L
authors.lastname: Hegedüs
mesh_terms: D000368:Aged; D005240:Feasibility Studies; D005260:Female; D057086:High-Intensity Focused Ultrasound Ablation / Q000009:adverse effects; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000628:therapy*; D008875:Middle Aged; D010865:Pilot Projects