title: Dynamic contrast-enhanced magnetic resonance imaging predicts immediate therapeutic response of magnetic resonance-guided high-intensity focused ultrasound ablation of symptomatic uterine fibroids.
abstract: OBJECTIVE
  : To evaluate dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters in the prediction of the immediate therapeutic response of MR-guided high-intensity focused ultrasound (HIFU) therapy in the treatment of symptomatic uterine fibroids
  
  
  METHODS
  : Institutional review board approved this study, and informed consent was obtained from all participants. A total of 10 symptomatic uterine fibroids (diameter: mean, 8.9 cm; range, 4.7-12 cm) in 10 female patients (mean age, 42.2 years) were treated with MR-HIFU therapy using the volumetric ablation technique. DCE-MRI and conventional contrast-enhanced MRI were obtained as a baseline and as an immediate follow-up study, respectively. After regions of interest of each treatment cell were properly registered to both MRI studies, DCE-MRI parameters (K, ve, vp) and operator-controllable therapy parameters (power, treatment cell size, sonication depth) were investigated on a cell-by-cell basis to reflect tissue inhomogeneity. Two types of ablation efficacy indices (volume of 240 equivalent minutes at 43°C/treatment-cell volume, nonperfused volume/treatment-cell volume) were then correlated with those parameters using multiple linear regression analysis to determine which factors were significant predictors for ablation efficacy.
  
  
  RESULTS
  : We used 293 treatment cells (4 mm, n = 12; 8 mm, n = 115; 12 mm, n = 149; 16 mm, n = 17), and all of them were analyzable. Ablation efficacies were 1.06 ± 0.58 and 0.67 ± 0.39. K (B = -12.035, P < 0.001 and B = -11.516, P < 0.001, respectively) among DCE-MRI parameters and acoustic power (B = 0.008, P < 0.001; B = 0.010, P < 0.001, respectively) among therapy parameters were revealed to be independently significant predictors for both types of ablation efficacy.
  
  
  CONCLUSIONS
  : A higher K value at baseline DCE-MRI suggested a poor ablation efficacy of MR-HIFU therapy for symptomatic uterine fibroids.
authors.affiliation: Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Young-Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Hyo K
authors.initials: HK
authors.lastname: Lim
authors.forename: Jae-Hun
authors.initials: JH
authors.lastname: Kim
authors.forename: Hyunchul
authors.initials: H
authors.lastname: Rhim
authors.forename: Byung Kwan
authors.initials: BK
authors.lastname: Park
authors.forename: Bilgin
authors.initials: B
authors.lastname: Keserci
authors.forename: Max O
authors.initials: MO
authors.lastname: Köhler
authors.forename: Duk-Soo
authors.initials: DS
authors.lastname: Bae
authors.forename: Byoung-Gie
authors.initials: BG
authors.lastname: Kim
authors.forename: Jeong-Won
authors.initials: JW
authors.lastname: Lee
authors.forename: Tae-Joong
authors.initials: TJ
authors.lastname: Kim
authors.forename: Shunmugavelu
authors.initials: S
authors.lastname: Sokka
authors.forename: Jung Hee
authors.initials: JH
authors.lastname: Lee
mesh_terms: D000328:Adult; D003287:Contrast Media; D005260:Female; D006571:Heterocyclic Compounds; D057086:High-Intensity Focused Ultrasound Ablation; D006801:Humans; D016018:Least-Squares Analysis; D007889:Leiomyoma / Q000473:pathology / Q000628:therapy*; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000379:methods*; D053783:Magnetic Resonance Imaging, Interventional / Q000379:methods*; D008875:Middle Aged; D009942:Organometallic Compounds; D011237:Predictive Value of Tests; D011446:Prospective Studies; D016896:Treatment Outcome; D014594:Uterine Neoplasms / Q000473:pathology / Q000628:therapy*
chemical_list: D003287:Contrast Media; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C050823:gadolinium 1,4,7,10-tetraazacyclododecane-N,N',N'',N'''-tetraacetate