title: In-vitro and in-vivo histochemical and thermal studies using a thermal balloon endometrial ablation system for varying treatment times.
abstract: BACKGROUND
  To assess the immediate zone of thermal necrosis (ZTN) using an enzyme histochemical staining technique and serosal temperatures for the Cavaterm endometrial balloon ablation system for different treatment times.
  
  
  METHODS
  A thermal balloon ablation was performed initially post- (n = 6) and subsequently pre-hysterectomy (n = 15). Eight to 12 tissue blocks from each uterus were sectioned and stained using diaphorase respiratory enzyme techniques. Patients in the in-vivo group had temperature measurements taken from four serosal points, a myometrial gradient profile, the balloon surface and the endocervical canal.
  
  
  RESULTS
  The serosal temperature sensors did not demonstrate any rise in temperature above 44.1 degrees C. The mean temperature at the anterior wall, posterior wall, fundus and cornual areas was 37.1 (SD 1.3), 36.8 (SD 1.0), 37.4 (SD 1.8) and 36.7 degrees C (SD 1.0), respectively. The immediate mean maximum ZTN was greatest for the 15-min treatment time (3.1 mm, SD 1.5) compared to the 10- and 7-min treatment times (3.0 mm, SD 1.4 and 2.2 mm, SD 0.7, respectively). The maximum ZTN recorded was 5.6 mm. No full thickness injuries were demonstrated either histochemically or suggested by the temperature studies.
  
  
  CONCLUSIONS
  This study confirms that Cavaterm thermal balloon ablation produces a reproducible thermal injury without evidence of serosal heating. Results suggest that the treatment time could be reduced to 10-min with no detrimental effect on the clinical outcomes. This hypothesis is currently being evaluated by clinical trials.
authors.affiliation: Countess of Chester Hospital, Liverpool Road, Chester, UK.
authors.forename: Jeremy
authors.initials: J
authors.lastname: Hawe
authors.forename: Jason
authors.initials: J
authors.lastname: Abbott
authors.forename: Graham
authors.initials: G
authors.lastname: Phillips
authors.forename: Nafisa
authors.initials: N
authors.lastname: Wilkinson
authors.forename: Sean
authors.initials: S
authors.lastname: Duffy
authors.forename: Ray
authors.initials: R
authors.lastname: Garry
mesh_terms: D005260:Female; D006801:Humans; D006979:Hyperthermia, Induced / Q000379:methods*; D007044:Hysterectomy; D007124:Immunoenzyme Techniques; D010535:Laparoscopy; D009336:Necrosis; D014592:Uterine Hemorrhage / Q000628:therapy*