title: Shear wave elastography assessment in the prostate: an intraobserver reproducibility study.
abstract: OBJECTIVE
  To assess the intraobserver reproducibility of shear wave elastography (SWE) in the prostate.
  
  
  METHODS
  This study was institutional review board approved with waiver of informed consent. Eighty men (mean age, 66.2±9.2years) with suspected prostate cancer underwent SWE. Young modulus (kPa) was measured at 24 locations in the prostate (superficial and deep locations in paramedian and lateral aspects at the base, mid-gland, and apex levels). The intraobserver reproducibility of two repeated measurements was determined using intraclass correlation coefficients (ICC) and was compared among measurement location, prostate volume, age, and prostate-specific antigen level.
  
  
  RESULTS
  The overall intraobserver reproducibility was excellent (ICC=0.876). In addition, intraobserver reproducibility was excellent for all specified subgroups according to location, prostate volume, and clinical variables (ICC=0.826-0.917). With regard to location, SWE measurements showed substantially higher ICC values in the mid-gland than in the base and apex, in the paramedian prostate than in the lateral prostate, and in superficial locations than in deeper locations. No substantial differences in ICC values were observed according to the prostate volume and clinical variables.
  
  
  CONCLUSIONS
  Intraobserver reproducibility of SWE measurements in the prostate gland was excellent. There was variability in the intraobserver reproducibility according to location within the prostate, and the operator should be aware of this and take extra caution when performing SWE in these areas.
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea.
authors.forename: Sungmin
authors.initials: S
authors.lastname: Woo
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea. Electronic address: iwishluv@empas.com.
authors.forename: Sang Youn
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea.
authors.forename: Myoung Seok
authors.initials: MS
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea; Institute of Radiation Medicine and Kidney Research Institute, Seoul National University Medical Research Center, Seoul 110-744, Korea.
authors.forename: Jeong Yeon
authors.initials: JY
authors.lastname: Cho
authors.affiliation: Department of Radiology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Korea; Institute of Radiation Medicine and Kidney Research Institute, Seoul National University Medical Research Center, Seoul 110-744, Korea.
authors.forename: Seung Hyup
authors.initials: SH
authors.lastname: Kim
mesh_terms: D000368:Aged; D055119:Elastic Modulus; D054459:Elasticity Imaging Techniques; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009929:Organ Size; D011467:Prostate / Q000000981:diagnostic imaging* / Q000473:pathology; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D017430:Prostate-Specific Antigen
keywords: Intraobserver reproducibility; Prostate; Shear wave elastography; Young modulus