title: Transabdominal high-intensity focused ultrasound therapy of the prostate and determination of the protective effect of rectal cooling: an experimental study using canine prostates.
abstract: OBJECTIVE
  The purpose of this study was to report our initial experience with transabdominal high-intensity focused ultrasound (HIFU) therapy of the canine prostate and to determine the protective effect of rectal cooling during HIFU therapy.
  
  
  METHODS
  Fifteen male dogs underwent transabdominal HIFU therapy of the prostate. Transabdominal HIFU was performed on 9 dogs without using a rectal cooling device, and the remaining 6 dogs underwent transabdominal HIFU with introduction of the rectal cooling device. Magnetic resonance imaging (MRI) was performed before, immediately after, and 1 week after the HIFU procedure. Rectal changes on MRI were classified into 4 grades (grades 0-3), and a comparison of the rectal change grades on MRI between the two groups was performed with the Mann-Whitney U test.
  
  
  RESULTS
  The procedure failed for the first dog because of inadequate skin preparation. Of the remaining 14 dogs (8 without rectal cooling and 6 with rectal cooling), 4 showed focal signal changes in the prostate. The average rectal change grades on immediate postprocedural MRI were 2.63 for the non-rectal cooling group and 1.17 for the rectal cooling group (P = .0216). On 1-week follow-up MRI, the average grades were 1.20 for the non-rectal cooling group and 0.33 for the rectal cooling group (P = .1956).
  
  
  CONCLUSIONS
  Transabdominal HIFU of the canine prostate was technically feasible, but the effect was limited because of anatomic and physiologic factors of the canine prostate. The rectal cooling device seems to have a protective effect on the rectum during the transabdominal HIFU procedure.
authors.affiliation: Department of Radiology, Seoul National University Hospital, Seoul 110-744, Korea.
authors.forename: Dong Hyun
authors.initials: DH
authors.lastname: Yoo
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Cho
authors.forename: Cheol
authors.initials: C
authors.lastname: Kwak
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Kyung Chul
authors.initials: KC
authors.lastname: Moon
authors.forename: Seung Hyup
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000818:Animals; D001831:Body Temperature; D002056:Burns / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control*; D004285:Dogs; D057086:High-Intensity Focused Ultrasound Ablation / Q000009:adverse effects*; D007036:Hypothermia, Induced / Q000379:methods*; D008297:Male; D058958:Organs at Risk / Q000503:physiopathology / Q000528:radiation effects; D011467:Prostate / Q000601:surgery*; D011468:Prostatectomy / Q000009:adverse effects / Q000379:methods; D012007:Rectum / Q000293:injuries* / Q000503:physiopathology* / Q000528:radiation effects; D016896:Treatment Outcome
keywords: cold temperature; dog; high-intensity focused ultrasound; prostate; rectum; transabdominal