title: Prostate biopsies guided by three-dimensional real-time (4-D) transrectal ultrasonography on a phantom: comparative study versus two-dimensional transrectal ultrasound-guided biopsies.
abstract: OBJECTIVE
  This study evaluated the accuracy in localisation and distribution of real-time three-dimensional (4-D) ultrasound-guided biopsies on a prostate phantom.
  
  
  METHODS
  A prostate phantom was created. A three-dimensional real-time ultrasound system with a 5.9MHz probe was used, making it possible to see several reconstructed orthogonal viewing planes in real time. Fourteen operators performed biopsies first under 2-D then 4-D transurethral ultrasound (TRUS) guidance (336 biopsies). The biopsy path was modelled using segmentation in a 3-D ultrasonographic volume. Special software was used to visualise the biopsy paths in a reference prostate and assess the sampled area. A comparative study was performed to examine the accuracy of the entry points and target of the needle. Distribution was assessed by measuring the volume sampled and a redundancy ratio of the sampled prostate.
  
  
  RESULTS
  A significant increase in accuracy in hitting the target zone was identified using 4-D ultrasonography as compared to 2-D. There was no increase in the sampled volume or improvement in the biopsy distribution with 4-D ultrasonography as compared to 2-D.
  
  
  CONCLUSIONS
  The 4-D TRUS guidance appears to show, on a synthetic model, an improvement in location accuracy and in the ability to reproduce a protocol. The biopsy distribution does not seem improved.
authors.affiliation: Urological Surgery and Renal Transplantation Unit, Grenoble University Hospital Centre, Grenoble, France. JALong@chu-grenoble.fr
authors.forename: Jean-Alexandre
authors.initials: JA
authors.lastname: Long
authors.forename: Vincent
authors.initials: V
authors.lastname: Daanen
authors.forename: Alexandre
authors.initials: A
authors.lastname: Moreau-Gaudry
authors.forename: Jocelyne
authors.initials: J
authors.lastname: Troccaz
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Rambeaud
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Descotes
mesh_terms: D006801:Humans; D008297:Male; D019047:Phantoms, Imaging; D011467:Prostate / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000473:pathology*; D012007:Rectum; D014463:Ultrasonography / Q000379:methods*