title: Intravoxel Incoherent Motion Diffusion-Weighted Magnetic Resonance Imaging of Cervical Cancer With Different b-Values.
abstract: OBJECTIVE
  The aims of this study were to evaluate the dependence of diffusion parameters on the b values adopted for intravoxel incoherent motion diffusion-weighted magnetic resonance imaging and to investigate the application value of multiple diffusion parameters obtained from monoexponential and biexponential models in subjects with a normal cervix and in cervical cancer patients.
  
  
  METHODS
  A total of 120 female patients with cervical cancer and 21 female control subjects with a normal cervix underwent diffusion-weighted magnetic resonance imaging with 13 b values (0-2000 s/mm) at 3 T. The standard apparent diffusion coefficient (Dst), diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) were calculated by fitting with monoexponential and biexponential models at 2 different ranges of b values: 0 to 1000 and 0 to 2000 s/mm. A univariate analysis was performed to identify factors that could distinguish cervical carcinoma from normal cervical tissue. Parameters that correlated with the pathological grade and stage of cervical cancer were also evaluated. Receiver operating characteristic curves were used to evaluate the diagnostic efficiency of every parameter.
  
  
  RESULTS
  All the tested parameters, except the D* of the 2 different ranges of b value groups, significantly differed between the patients with cervical carcinoma and control subjects (P < 0.01). D2000, Dst2000, and D1000 showed comparable diagnostic value, with an area under the curve of 0.923, 0.909, and 0.907, respectively. Dst2000, D2000, Dst1000, and D1000 differed significantly among the 3 degrees of cervical stromal infiltration depth (P < 0.05).
  
  
  CONCLUSIONS
  D2000 and Dst2000 tended to outperform D1000 in terms of diagnostic efficiency, but there was no significant difference in their ability to differentiate cervical carcinoma from normal cervix. Cervical cancers with lower Dst and D values tended to have greater infiltration depth.
authors.affiliation: From the *Radiological Department, †Pathological Department, ‡Obstetrics and Gynaecological Department, and §Radiotherapeutical Department, Henan Provincial People's Hospital and the People's Hospital of Zhengzhou University, Zhengzhou, Henan, China.
authors.forename: Qingxia
authors.initials: Q
authors.lastname: Wu
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Ligang
authors.initials: L
authors.lastname: Shi
authors.forename: Li
authors.initials: L
authors.lastname: Dong
authors.forename: Mingbo
authors.initials: M
authors.lastname: Liu
authors.forename: Shewei
authors.initials: S
authors.lastname: Dou
authors.forename: Shaocheng
authors.initials: S
authors.lastname: Zhu
authors.forename: Meiyun
authors.initials: M
authors.lastname: Wang
authors.forename: Dapeng
authors.initials: D
authors.lastname: Shi
mesh_terms: D000328:Adult; D000368:Aged; D002584:Cervix Uteri / Q000000981:diagnostic imaging; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008875:Middle Aged; D009038:Motion; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging*