title: Evaluation of MRI-TRUS fusion versus cognitive registration accuracy for MRI-targeted, TRUS-guided prostate biopsy.
abstract: OBJECTIVE
  The purpose of this article is to compare transrectal ultrasound (TRUS) biopsy accuracies of operators with different levels of prostate MRI experience using cognitive registration versus MRI-TRUS fusion to assess the preferred method of TRUS prostate biopsy for MRI-identified lesions. SUBJECTS AND METHODS; One hundred patients from a prospective prostate MRI-TRUS fusion biopsy study were reviewed to identify all patients with clinically significant prostate adenocarcinoma (PCA) detected on MRI-targeted biopsy. Twenty-five PCA tumors were incorporated into a validated TRUS prostate biopsy simulator. Three prostate biopsy experts, each with different levels of experience in prostate MRI and MRI-TRUS fusion biopsy, performed a total of 225 simulated targeted biopsies on the MRI lesions as well as regional biopsy targets. Simulated biopsies performed using cognitive registration with 2D TRUS and 3D TRUS were compared with biopsies performed under MRI-TRUS fusion.
  
  
  RESULTS
  Two-dimensional and 3D TRUS sampled only 48% and 45% of clinically significant PCA MRI lesions, respectively, compared with 100% with MRI-TRUS fusion. Lesion sampling accuracy did not statistically significantly vary according to operator experience or tumor volume. MRI-TRUS fusion-naïve operators showed consistent errors in targeting of the apex, midgland, and anterior targets, suggesting that there is biased error in cognitive registration. The MRI-TRUS fusion expert correctly targeted the prostate apex; however, his midgland and anterior mistargeting was similar to that of the less-experienced operators.
  
  
  CONCLUSIONS
  MRI-targeted TRUS-guided prostate biopsy using cognitive registration appears to be inferior to MRI-TRUS fusion, with fewer than 50% of clinically significant PCA lesions successfully sampled. No statistically significant difference in biopsy accuracy was seen according to operator experience with prostate MRI or MRI-TRUS fusion.
authors.affiliation: 1 Department of Medical Imaging, Robarts Research Institute, University of Western Ontario, London, ON, Canada.
authors.forename: Derek W
authors.initials: DW
authors.lastname: Cool
authors.forename: Xuli
authors.initials: X
authors.lastname: Zhang
authors.forename: Cesare
authors.initials: C
authors.lastname: Romagnoli
authors.forename: Jonathan I
authors.initials: JI
authors.lastname: Izawa
authors.forename: Walter M
authors.initials: WM
authors.lastname: Romano
authors.forename: Aaron
authors.initials: A
authors.lastname: Fenster
mesh_terms: D002983:Clinical Competence / Q000706:statistics & numerical data*; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000706:statistics & numerical data*; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D011471:Prostatic Neoplasms / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique / Q000706:statistics & numerical data*; D013647:Task Performance and Analysis
keywords: 3D transrectal ultrasound; MRI fusion biopsy; MRI–transrectal ultrasound fusion; prostate MRI; prostate biopsy