title: Feasibility of Computed Diffusion Weighted Imaging and Optimization of b-value in Cervical Cancer.
abstract: OBJECTIVE
  To evaluate the feasibility of computed diffusion weighted imaging (DWI) in cervical cancer and investigate the optimal b-value using computed DWI.
  
  
  METHODS
  The present retrospective study involved 85 patients with cervical cancer in the International Federation of Gynecology and Obstetrics (FIGO) stage IB, IIA or IIB. DWI was obtained with b-values of 0, 100, 500 and 1000 s/mm2. Computed DWI with b-values of 800, 1000, 1300, 1600 and 2000 s/mm2(cDWI800, cDWI1000, cDWI1300, cDWI1600, cDWI2000) were generated from all measured DWI (mDWI) data. Qualitatively, computed DWI was evaluated in terms of tumor conspicuity, signal suppression of the fat in the imaged area and total image quality by two radiologists independently with reference to mDWI with b-value of 1000 s/mm2. The b-value at which the signal of the endocervical canal was suppressed was recorded. Quantitatively, the signal intensities of tumor, myometrium, endocervical canal, endometrium, and gluteal subcutaneous fat were measured and represented as contrast ratios (CR).
  
  
  RESULTS
  Regarding tumor conspicuity and total image quality, significantly higher scores were obtained at cDWI1300and cDWI1600compared to the others (post-hoc comparison, P < 0.001), except for the total image quality between cDWI1000and cDWI1600in one reader. Signal suppression of the fat was the worst at cDWI2000. The signal intensity of the endocervical canal was suppressed in 24/27 cases on cDWI1600and in 26/27 cases on cDWI2000. The CRs of tumor to myometrium, cervix, and endometrium increased with higher b-values, while the CRs of tumor to fat decreased and were statistically significant (post-hoc comparison, P < 0.001).
  
  
  CONCLUSIONS
  Computed DWI with the b-values of 1300 and 1600 would be suitable for the evaluation of cervical cancer due to good tumor conspicuity.
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University.
authors.forename: Yusaku
authors.initials: Y
authors.lastname: Moribata
authors.forename: Aki
authors.initials: A
authors.lastname: Kido
authors.forename: Koji
authors.initials: K
authors.lastname: Fujimoto
authors.forename: Yuki
authors.initials: Y
authors.lastname: Himoto
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Kurata
authors.forename: Fuki
authors.initials: F
authors.lastname: Shitano
authors.forename: Kayo
authors.initials: K
authors.lastname: Kiguchi
authors.forename: Ikuo
authors.initials: I
authors.lastname: Konishi
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002584:Cervix Uteri / Q000000981:diagnostic imaging / Q000473:pathology; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008875:Middle Aged; D015203:Reproducibility of Results; D012189:Retrospective Studies; D002583:Uterine Cervical Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology