Christopher M Brede1, Nicholas J Douville2, Stephen Jones1. 1. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, Ohio, USA. 2. Department of Biomedical Engineering, University of Michigan, Ann Arbor, Mich., USA.
Abstract
PURPOSE: Transperineal template prostate biopsy has been proposed to facilitate systematic biopsy in patients undergoing repeat biopsy who are at high risk for cancer. Advocates tout the reliability of the grid to define biopsy location compared to hand-held transrectal ultrasound guided biopsy. However, accuracy of the biopsy needle depends on bevel position, tissue deformity, and technique. Due to this potential for error, we sought to determine whether the use of transperineal template biopsy would assure reproducibly accurate needle placement. MATERIALS AND METHODS: A standard 0.5 cm brachytherapy grid was utilized for transperineal biopsy. A single grid hole was used to obtain biopsies. The bevel of the needle was rotated to a different position with each biopsy, and the angle of the needle was varied to test the ability of the grid to "map" the prostate. RESULTS: We observed wide variation of needle location through a single brachytherapy grid hole. We are able to show that at 5 cm depth, an area of 2.47 mm(2) is possible to biopsy and at a depth of 25 cm; approximately 7.56 mm(2) is possible to biopsy. This gives a precision of biopsy of at the most shallow depth 22% and at the deepest 7%. CONCLUSION: There is potential for technical and equipment associated error with transperineal template guided prostate biopsy. The grid alone can account for substantial sources of error, so technique remains critical if the grid coordinates are to be used to predict presence or extent of cancer.
PURPOSE: Transperineal template prostate biopsy has been proposed to facilitate systematic biopsy in patients undergoing repeat biopsy who are at high risk for cancer. Advocates tout the reliability of the grid to define biopsy location compared to hand-held transrectal ultrasound guided biopsy. However, accuracy of the biopsy needle depends on bevel position, tissue deformity, and technique. Due to this potential for error, we sought to determine whether the use of transperineal template biopsy would assure reproducibly accurate needle placement. MATERIALS AND METHODS: A standard 0.5 cm brachytherapy grid was utilized for transperineal biopsy. A single grid hole was used to obtain biopsies. The bevel of the needle was rotated to a different position with each biopsy, and the angle of the needle was varied to test the ability of the grid to "map" the prostate. RESULTS: We observed wide variation of needle location through a single brachytherapy grid hole. We are able to show that at 5 cm depth, an area of 2.47 mm(2) is possible to biopsy and at a depth of 25 cm; approximately 7.56 mm(2) is possible to biopsy. This gives a precision of biopsy of at the most shallow depth 22% and at the deepest 7%. CONCLUSION: There is potential for technical and equipment associated error with transperineal template guided prostate biopsy. The grid alone can account for substantial sources of error, so technique remains critical if the grid coordinates are to be used to predict presence or extent of cancer.
Authors: E David Crawford; Shandra S Wilson; Kathleen C Torkko; Daisaku Hirano; J Scott Stewart; Craig Brammell; R Storey Wilson; Nozomu Kawata; Holly Sullivan; M Scott Lucia; Priya N Werahera Journal: BJU Int Date: 2005-11 Impact factor: 5.588
Authors: David M Pinkstaff; Todd C Igel; Steven P Petrou; Gregory A Broderick; Michael J Wehle; Paul R Young Journal: Urology Date: 2005-04 Impact factor: 2.649
Authors: Gregory S Merrick; Sarah Gutman; Hugo Andreini; Walter Taubenslag; David L Lindert; Rodney Curtis; Edward Adamovich; Richard Anderson; Zachariah Allen; Wayne Butler; Kent Wallner Journal: Eur Urol Date: 2007-02-23 Impact factor: 20.096
Authors: M Remzi; B Djavan; R Wammack; M Momeni; C Seitz; B Erne; M Dobrovits; S Alavi; M Marberger Journal: Urology Date: 2003-01 Impact factor: 2.649