title: Benign prostatic hyperplasia: value of MR imaging for determining histologic type.
abstract: OBJECTIVE
  To assess the value of magnetic resonance (MR) imaging for determining the histologic type of benign prostatic hyperplasia (BPH).
  
  
  METHODS
  Unenhanced T1- and T2-weighted images and gadolinium-enhanced T1-weighted images were obtained in the transverse plane at 1.5 T in 33 patients with BPH. Hyperphasia was classified as stromal or nonstromal. Nonstromal hyperplasia was diagnosed if (a) the nodules in the inner gland had heterogeneous high signal intensity on T2-weighted images and peripheral enhancement on gadolinium-enhanced images, (b) a surgical capsule was present, or (c) the inner gland volume to total volume ratio was greater than 0.75.
  
  
  RESULTS
  A correct diagnosis was made with MR imaging in 23 of 24 patients with nonstromal hyperplasia and eight of nine with stromal hyperplasia (94% accuracy). In nonstromal hyperplasia, nodular lesions were seen in 20 patients and a surgical capsule was seen in 19. Eighteen patients had a transition zone ratio greater than 0.75.
  
  
  CONCLUSIONS
  MR imaging appears to be useful for choosing the type of pharmacotherapy performed because accurate histologic assessment is possible.
authors.affiliation: Department of Radiology, Shimane Medical University, Enya Izumo, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Ishida
authors.forename: K
authors.initials: K
authors.lastname: Sugimura
authors.forename: H
authors.initials: H
authors.lastname: Okizuka
authors.forename: Y
authors.initials: Y
authors.lastname: Kaji
authors.forename: M
authors.initials: M
authors.lastname: Moriyama
authors.forename: S
authors.initials: S
authors.lastname: Nagaoka
authors.forename: M
authors.initials: M
authors.lastname: Mizutani
authors.forename: T
authors.initials: T
authors.lastname: Ishida
mesh_terms: D000368:Aged; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011470:Prostatic Hyperplasia / Q000175:diagnosis* / Q000473:pathology