title: Vibro-acoustography imaging of permanent prostate brachytherapy seeds in an excised human prostate--preliminary results and technical feasibility.
abstract: OBJECTIVE
  The objective in this work is to investigate the feasibility of using a new imaging tool called vibro-acoustography (VA) as a means of permanent prostate brachytherapy (PPB) seed localization to facilitate post-implant dosimetry (PID).
  
  
  METHODS
  Twelve OncoSeed (standard) and eleven EchoSeed (echogenic) dummy seeds were implanted in a human cadaver prostate. Seventeen seeds remained after radical retropubic prostatectomy. VA imaging was conducted on the prostate that was cast in a gel phantom and placed in a tank of degassed water. 2-D magnitude and phase VA image slices were obtained at different depths within the prostate showing location and orientation of the seeds.
  
  
  RESULTS
  VA demonstrates that twelve of seventeen (71%) seeds implanted were visible in the VA image, and the remainder were obscured by intra-prostatic calcifications. Moreover, it is shown here that VA is capable of imaging and locating PPB seeds within the prostate independent of seed orientation, and the resulting images are speckle free.
  
  
  CONCLUSIONS
  The results presented in this research show that VA allows seed detection within a human prostate regardless of their orientation, as well as imaging intra-prostatic calcifications.
authors.affiliation: Mayo Clinic College of Medicine, Department of Physiology and Biomedical Engineering, Ultrasound Research Laboratory, Rochester, MN 55905, USA. mitri.farid@mayo.edu
authors.forename: F G
authors.initials: FG
authors.lastname: Mitri
authors.forename: B J
authors.initials: BJ
authors.lastname: Davis
authors.forename: M W
authors.initials: MW
authors.lastname: Urban
authors.forename: A
authors.initials: A
authors.lastname: Alizad
authors.forename: J F
authors.initials: JF
authors.lastname: Greenleaf
authors.forename: G H
authors.initials: GH
authors.lastname: Lischer
authors.forename: T M
authors.initials: TM
authors.lastname: Wilson
authors.forename: M
authors.initials: M
authors.lastname: Fatemi
mesh_terms: D001918:Brachytherapy / Q000295:instrumentation*; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005240:Feasibility Studies; D006801:Humans; D008297:Male; D010865:Pilot Projects; D011467:Prostate / Q000000981:diagnostic imaging* / Q000601:surgery*; D019919:Prosthesis Implantation / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity