title: MR measurement of luminal water in prostate gland: Quantitative correlation between MRI and histology.
abstract: To determine the relationship between parameters measured from luminal water imaging (LWI), a new magnetic resonance imaging (MRI) T2mapping technique, and the corresponding tissue composition in prostate.
  
  
  
  In all, 17 patients with prostate cancer were examined with a 3D multiecho spin echo sequence at 3T prior to undergoing radical prostatectomy. Maps of seven MR parameters, called N, T2-short, T2-long, Ashort, Along, geometric mean T2time (gmT2), and luminal water fraction (LWF), were generated using nonnegative least squares (NNLS) analysis of the T2decay curves. MR parametric maps were correlated to digitized whole-mount histology sections. Percentage area of tissue components, including luminal space, nuclei, and cytoplasm plus stroma, was measured on the histology sections by using color-based image segmentation. Spearman's rank correlation test was used to evaluate the correlation between MR parameters and the corresponding tissue components, with particular attention paid to the correlation between LWF and percentage area of luminal space.
  
  
  
  N, T2-short, Along, gmT2, and LWF showed significant correlation (P < 0.05) with percentage area of luminal space and stroma plus cytoplasm. T2-shortand gmT2also showed significant correlation (P < 0.05) with percentage area of nuclei. Overall, the strongest correlation was observed between LWF and luminal space (Spearman's coefficient of rank correlation = 0.75, P < 0.001).
  
  
  
  Results of this study show that LWF measured with MRI is strongly correlated with the fractional amount of luminal space in prostatic tissue. This result suggests that LWI can potentially be applied for evaluation of prostatic diseases in which the extent of luminal space differs between normal and abnormal tissues.
  
  
  
  1 Technical Efficacy: Stage 1 J. MAGN. RESON. IMAGING 2017;46:861-869.
authors.affiliation: Department of Physics and Astronomy, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Shirin
authors.initials: S
authors.lastname: Sabouri
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Ladan
authors.initials: L
authors.lastname: Fazli
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.|Department of Radiology, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Silvia D
authors.initials: SD
authors.lastname: Chang
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Richard
authors.initials: R
authors.lastname: Savdie
authors.affiliation: Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: Edward C
authors.initials: EC
authors.lastname: Jones
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: S Larry
authors.initials: SL
authors.lastname: Goldenberg
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Black
authors.affiliation: Department of Urologic Sciences, University of British Columbia, Vancouver, BC, Canada.|Vancouver Prostate Centre, Vancouver, BC, Canada.|Department of Radiology, University of British Columbia, Vancouver, BC, Canada.|UBC MRI Research Center, Vancouver, BC, Canada.
authors.forename: Piotr
authors.initials: P
authors.lastname: Kozlowski
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001834:Body Water / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011467:Prostate / Q000000981:diagnostic imaging*; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging*
keywords: MR T2 mapping; prostate; prostatic luminal space