title: Computed diffusion-weighted imaging using 3-T magnetic resonance imaging for prostate cancer diagnosis.
abstract: OBJECTIVE
  To assess the efficacy of computed diffusion-weighted images (cDWIs) of b = 2000 s/mm(2) (cDWI2000) generated from DWIs of b = 0 and 1000 for prostate cancer (PCa) diagnosis in comparison with that of measured original DWIs of b = 1000 (mDWI1000) and b = 2000(mDWI2000) using 3-T MRI.
  
  
  METHODS
  Eighty patients who underwent a preoperative MRI examination, including T2WI and DWI (b = 0, 1000, 2000 s/mm(2)), were enrolled in this study. Four combinations of images, protocol A (T2WI alone), B (T2WI + mDWI1000), C (T2WI + mDWI2000) and D (T2WI + cDWI2000), were assessed for their diagnostic capability. Areas under the receiver operating characteristic curve (Az) and diagnostic performance were evaluated, as well as contrast ratios (CR) between cancerous and non-cancerous lesions for each DWI.
  
  
  RESULTS
  The highest CR was obtained with cDWI2000 (0.29 ± 0.16). Sensitivity, specificity, accuracy, and Az of the protocols were: A: 66.3 %, 59.4 %, 63.0 %, 0.67; B: 82.6 %, 62.0 %, 72.5 %, 0.80; C: 84.1 %, 66.5 %, 75.5 %, 0.86; D: 83.2 %, 70.0 %, 76.6 %, and 0.84, respectively The specificities and accuracies of protocol C and D were significantly higher than those of protocol B (P < 0.05).
  
  
  CONCLUSIONS
  cDWI2000 appears to be more effective than mDWI1000, and at least as effective as mDWI2000 for PCa diagnosis.
authors.affiliation: Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan, yonu0121@yahoo.co.jp.
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ueno
authors.forename: Satoru
authors.initials: S
authors.lastname: Takahashi
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kitajima
authors.forename: Tokunori
authors.initials: T
authors.lastname: Kimura
authors.forename: Ikuo
authors.initials: I
authors.lastname: Aoki
authors.forename: Fumi
authors.initials: F
authors.lastname: Kawakami
authors.forename: Hideaki
authors.initials: H
authors.lastname: Miyake
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Ohno
authors.forename: Kazuro
authors.initials: K
authors.lastname: Sugimura
mesh_terms: D000368:Aged; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005069:Evaluation Studies as Topic; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity