title: Osteoid osteoma: percutaneous treatment with radiofrequency energy.
abstract: OBJECTIVE
  To report our experience with technical success, complications, and long-term clinical success of radiofrequency (RF) ablation of osteoid osteoma.
  
  
  METHODS
  After needle biopsy, computed tomography (CT)-guided percutaneous RF ablation was performed with general or spinal anesthesia. With an RF electrode, the lesion was heated to 90 degrees C for 6 minutes. Patient age and sex, lesion size and location, biopsy results, and complications were recorded. Clinical success was assessed at a minimum of 2 years after the procedure. Significance of patient age and sex and lesion location and size as a predictor of biopsy result was tested by means of chi2 analysis. In addition, effects of patient age and sex, lesion location and size, and biopsy results on clinical success were tested with the Fisher exact test.
  
  
  RESULTS
  During an 11-year period, 263 patients who were suspected of having osteoid osteoma underwent 271 ablation procedures. All procedures were technically successful. There were two anesthesia-related complications (aspiration, cardiac arrest) and two minor procedure-related complications (cellulitis, sympathetic dystrophy). Results at biopsy were positive in 73% (197 of 271 biopsies). Two-year follow-up data were available for 126 procedures. The other procedures had been performed more recently or the patients could not be contacted. There was complete relief of symptoms after 112 of the 126 procedures (89%). For procedures performed as the initial treatment, the success rate was 91% (107 of 117 procedures). Procedures for recurrent lesions had a significantly lower success rate (six of 10 procedures [60%], P <.001). Clinical outcome was not dependent on biopsy result, patient age or sex, or lesion size or location.
  
  
  CONCLUSIONS
  CT-guided percutaneous RF ablation of osteoid osteoma is a safe and effective technique.
authors.affiliation: Department of Radiology, Massachusetts General Hospital, Harvard Medical School, 199 Cambridge Street, Boston, MA 02114, USA. dirosenthal@partners.org
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Rosenthal
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Hornicek
authors.forename: Martin
authors.initials: M
authors.lastname: Torriani
authors.forename: Mark C
authors.initials: MC
authors.lastname: Gebhardt
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Mankin
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery*; D017115:Catheter Ablation; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000601:surgery; D010017:Osteoma, Osteoid / Q000000981:diagnostic imaging / Q000601:surgery*; D015641:Radiography, Interventional; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed