title: Feasibility of Real-Time Intraprocedural Temperature Control during Bone Metastasis Thermal Microwave Ablation: A Bicentric Retrospective Study.
abstract: OBJECTIVE
  To evaluate feasibility of using a thermocouple for temperature monitoring during microwave (MW) ablation of metastatic bone disease.
  
  
  METHODS
  This retrospective study comprised 16 patients (8 men with mean age 63 y and 8 women with mean age 59 y) with 18 bone metastases treated with MW ablation using a thermocouple between March 2012 and October 2015. The mean maximum tumor size was 29.5 mm. MW ablation power was set between 15 W and 40 W and applied for 1-6 minutes. Thermocouple placements were as follows: epidural space (n = 7 cases), nerve roots (n = 9 cases), pleura (n = 1), and pericardium (n = 1). The procedure was considered technically successful when the MW and the thermocouple probes were accurately placed and thermoablation was initiated. Clinical success was defined as a 50% visual analog scale score decrease at 1 month as assessed by the operators.
  
  
  RESULTS
  Mean MW ablation time was 4.3 minutes with a mean energy of 30 W. Procedural success was 100%. In 16 cases with neural structure monitoring, temperature did not increase > 43°C. In 8 cases, MW ablation had to be discontinued because of temperature reaching 42°C. Efficacy of the procedure in regard to pain was achieved in 17 of 18 ablation sessions at 1 month.
  
  
  CONCLUSIONS
  Use of a thermocouple during bone MW ablation is a feasible technique and may be a potentially useful tool to help avoid nontarget ablation surrounding tumors.
authors.affiliation: Neuroradiology and MRI Unit, Service CLUNI, University Hospital, Boulevard du Gresivaudan, Grenoble 38000, France. Electronic address: adriankastler@gmail.com.
authors.forename: Adrian
authors.initials: A
authors.lastname: Kastler
authors.affiliation: Neuroradiology and MRI Unit, Service CLUNI, University Hospital, Boulevard du Gresivaudan, Grenoble 38000, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Krainik
authors.affiliation: Thoracic Oncology Department, University Hospital, Boulevard du Gresivaudan, Grenoble 38000, France.
authors.forename: Linda
authors.initials: L
authors.lastname: Sakhri
authors.affiliation: Oncology Department, University Hospital, Boulevard du Gresivaudan, Grenoble 38000, France.
authors.forename: Mireille
authors.initials: M
authors.lastname: Mousseau
authors.affiliation: Adult Radiology Department, Necker University Hospital, Paris Descartes University, Paris, France.
authors.forename: Bruno
authors.initials: B
authors.lastname: Kastler
mesh_terms: D055011:Ablation Techniques / Q000009:adverse effects; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001831:Body Temperature; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary / Q000601:surgery*; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D005602:France; D006801:Humans; D008297:Male; D008872:Microwaves / Q000009:adverse effects / Q000627:therapeutic use*; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000295:instrumentation / Q000379:methods*; D012189:Retrospective Studies; D012272:Ribs / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013125:Spinal Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary / Q000601:surgery*; D013249:Sternum / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013817:Thermography / Q000295:instrumentation; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014159:Transducers; D016896:Treatment Outcome