title: Automated real-time needle-guide tracking for fast 3-T MR-guided transrectal prostate biopsy: a feasibility study.
abstract: OBJECTIVE
  To assess the feasibility of automatic needle-guide tracking by using a real-time phase-only cross correlation ( POCC phase-only cross correlation ) algorithm-based sequence for transrectal 3-T in-bore magnetic resonance (MR)-guided prostate biopsies.
  
  
  METHODS
  This study was approved by the ethics review board, and written informed consent was obtained from all patients. Eleven patients with a prostate-specific antigen level of at least 4 ng/mL (4 μg/L) and at least one transrectal ultrasonography-guided biopsy session with negative findings were enrolled. Regions suspicious for cancer were identified on 3-T multiparametric MR images. During a subsequent MR-guided biopsy, the regions suspicious for cancer were reidentified and targeted by using the POCC phase-only cross correlation -based tracking sequence. Besides testing a general technical feasibility of the biopsy procedure by using the POCC phase-only cross correlation -based tracking sequence, the procedure times were measured, and a pathologic analysis of the biopsy cores was performed.
  
  
  RESULTS
  Thirty-eight core samples were obtained from 25 regions suspicious for cancer. It was technically feasible to perform the POCC phase-only cross correlation -based biopsies in all regions suspicious for cancer in each patient, with adequate biopsy samples obtained with each biopsy attempt. The median size of the region suspicious for cancer was 8 mm (range, 4-13 mm). In each region suspicious for cancer (median number per patient, two; range, 1-4), a median of one core sample per region was obtained (range, 1-3). The median time for guidance per target was 1.5 minutes (range, 0.7-5 minutes). Nineteen of 38 core biopsy samples contained cancer.
  
  
  CONCLUSIONS
  This study shows that it is feasible to perform transrectal 3-T MR-guided biopsies by using a POCC phase-only cross correlation algorithm-based real-time tracking sequence.
authors: From the Department of Radiology, St Radboud University Nijmegen Medical Center, UMC St Radboud, Internal Post Code 766, Postbus 9101, Geert Grooteplein 10, 6500 HB Nijmegen, the Netherlands (P.Z., M.G.S., J.O.B., J.J.F.); Department of Radiological Sciences, St Jude Children's Research Hospital, Memphis, Tenn (A.J.K.); Department of Imaging Physics, University of Texas-MD Anderson Cancer Center, Houston, Tex (F.M.); Department of Radiology, German Cancer Research Center, Heidelberg, Germany (H.P.S.); Department of Radiology, Division of Medical Physics, University of Freiburg, Freiburg, Germany (M.B.); and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, the Netherlands (J.J.F.).
authors: Patrik
authors: P
authors: Zamecnik
authors: Martijn G
authors: MG
authors: Schouten
authors: Axel J
authors: AJ
authors: Krafft
authors: Florian
authors: F
authors: Maier
authors: Heinz-Peter
authors: HP
authors: Schlemmer
authors: Jelle O
authors: JO
authors: Barentsz
authors: Michael
authors: M
authors: Bock
authors: Jurgen J
authors: JJ
authors: Fütterer
mesh_terms: D000368:Aged; D000465:Algorithms; D001331:Automation; D001707:Biopsy, Needle; D003287:Contrast Media; D006801:Humans; D053783:Magnetic Resonance Imaging, Interventional; D008297:Male; D008536:Meglumine; D008875:Middle Aged; D009942:Organometallic Compounds; D011471:Prostatic Neoplasms / Q000473:pathology*; D012007:Rectum; D013997:Time Factors
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D008536:Meglumine; C072417:gadoterate meglumine