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Construction and Evaluation of an Anatomically Correct Multi-Image Modality Compatible Phantom for Prostate Cancer Focal Ablation

2010; Lippincott Williams & Wilkins; Volume: 184; Issue: 1 Linguagem: Inglês

10.1016/j.juro.2010.03.001

1527-3792

Uri Lindner, Nathan Lawrentschuk, Robert Weersink, Orit E. Raz, Eugen Hlasny, Marshall S. Sussman, Sean M. Davidson, Mark R. Gertner, John Trachtenberg,

Laser-induced spectroscopy and plasma

No AccessJournal of UrologyInvestigative Urology1 Jul 2010Construction and Evaluation of an Anatomically Correct Multi-Image Modality Compatible Phantom for Prostate Cancer Focal Ablation Uri Lindner, Nathan Lawrentschuk, Robert A. Weersink, Orit Raz, Eugen Hlasny, Marshall S. Sussman, Sean R. Davidson, Mark R. Gertner, and John Trachtenberg Uri LindnerUri Lindner Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada , Nathan LawrentschukNathan Lawrentschuk Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada , Robert A. WeersinkRobert A. Weersink Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada , Orit RazOrit Raz Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada , Eugen HlasnyEugen Hlasny Joint Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario, Canada , Marshall S. SussmanMarshall S. Sussman Joint Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario, Canada , Sean R. DavidsonSean R. Davidson Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada , Mark R. GertnerMark R. Gertner Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada , and John TrachtenbergJohn Trachtenberg Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada View All Author Informationhttps://doi.org/10.1016/j.juro.2010.03.001AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Focal therapy using lasers is emerging as an alternative strategy for prostate cancer treatment. However, to our knowledge no anatomically correct models are available to test imaging and ablation techniques. Animal models present ethical, anatomical and cost challenges. We designed and validated an inexpensive but anatomically correct prostate phantom incorporating tumor, rectum and urethra that can be used for simulated and experimental magnetic resonance guided focal intervention. Our secondary aim was to asses the phantom using other imaging modalities. Materials and Methods: The phantom, which was constructed of ballistic gel, includes an 80 gm prostate with urethra, tumor, perineum and rectum. Gadolinium was added to make the gel visible to magnetic resonance imaging. To recreate a tumor an irregularly shaped 5 cc volume of coagulable gel was inserted into the prostate phantom. The phantom was evaluated using magnetic resonance, computerized tomography and transrectal ultrasound. Thermal ablation was delivered via interstitial placement of laser fibers. Magnetic resonance thermometry was done to record real-time tissue temperatures during thermal ablation. Results: With all modalities tested the phantom emulated human prostate anatomy. The coagulable gel tumor allowed us to generate focal thermal lesions. The phantom had magnetic resonance imaging properties comparable to in vivo properties, allowing ablative zones to be accurately assessed and magnetic resonance thermometry to be done. Conclusions: The phantom is a useful tool to test different aspects of thermal focal ablation for prostate cancer using multiple imaging modalities, particularly magnetic resonance. It is inexpensive and easily constructed, and may be considered a valuable model to train on and teach focal therapy. References 1 : Cancer statistics, 2008. CA Cancer J Clin2008; 58: 71. Google Scholar 2 : Quality of life and satisfaction with outcome among prostate-cancer survivors. N Engl J Med2008; 358: 1250. Google Scholar 3 : What percentage of patients with newly diagnosed carcinoma of the prostate are candidates for surveillance?: An analysis of the CaPSURE database. J Urol2008; 180: 1330. Link, Google Scholar 4 : Feasibility study: watchful waiting for localized low to intermediate grade prostate carcinoma with selective delayed intervention based on prostate specific antigen, histological and/or clinical progression. J Urol2002; 167: 1664. Link, Google Scholar 5 : Radical prostatectomy findings in patients in whom active surveillance of prostate cancer fails. J Urol2009; 182: 2274. Link, Google Scholar 6 : Focal therapy for localized prostate cancer—choosing the middle ground. Can Urol Assoc J2009; 3: 333. Google Scholar 7 : Focal therapy for prostate cancer: analysis by an international panel. Urology2008; 72: S1. Google Scholar 8 : MR-guided laser thermal ablation of primary and secondary liver tumours. Clin Radiol2003; 58: 112. Google Scholar 9 : Real-time magnetic resonance-guided laser thermal therapy for focal metastatic brain tumors. Neurosurgery2008; 63. ONS21. Google Scholar 10 : Magnetic resonance imaging-guided laser thermal ablation of renal tumours. BJU Int2002; 90: 814. Google Scholar 11 : MR-guided laser-induced thermotherapy in recurrent extrahepatic abdominal tumors. Eur Radiol2001; 11: 2041. Google Scholar 12 : Rationale for a "male lumpectomy," a prostate cancer targeted approach using cryoablation: results in 21 patients with at least 2 years of follow-up. Cardiovasc Intervent Radiol2008; 31: 98. Google Scholar 13 : Focal therapy with high-intensity-focused ultrasound in the treatment of localized prostate cancer. Jpn J Clin Oncol2008; 38: 192. Google Scholar 14 : Image guided photothermal focal therapy for localized prostate cancer: phase I trial. J Urol2009; 182: 1371. Link, Google Scholar 15 : Alternatives to animal experimentation: the regulatory background. Toxicol Appl Pharmacol2005; 207: 388. Google Scholar 16 : The 3R principle and the use of non-human primates in the study of neurodegenerative diseases: the case of Parkinson's disease. Neurosci Biobehav Rev2009; 33: 33. Google Scholar 17 : Laser therapy in dogs and humans—is there a difference?. Br J Urol1997; 79: 385. Google Scholar 18 Leenstra JL, Davis BJ, Wilson TM et al: Prostate dimensions and volume in 700 patients undergoing primary surgical or radiotherapeutic management of localized adenocarcinoma: implications for design of minimally invasive prostate cancer devices. Presented at annual meeting of American Society for Therapeutic and Radiation Oncology, Los Angeles, California, October 28–November 1, 2007, abstract 2317. Google Scholar 19 : Preparing ballistic gelatine—review and proposal for a standard method. Forensic Sci Int2004; 141: 91. Google Scholar 20 : Consistency of alginate impression materials and their evaluation. J Oral Rehabil1999; 26: 203. Google Scholar 21 : In vitro studies and computer simulations to assess the use of a diode laser (850 nm) for laser-induced thermotherapy (LITT). Lasers Surg Med1996; 18: 22. Google Scholar 22 : Magnetic resonance thermometry for predicting thermal damage: an application of interstitial laser coagulation in an in vivo canine prostate model. Magn Reson Med2000; 44: 873. Google Scholar 23 : Ex vivo tissue-type independence in proton-resonance frequency shift MR thermometry. Magn Reson Med1998; 40: 454. Google Scholar 24 : Screening and prostate-cancer mortality in a randomized European study. N Engl J Med2009; 360: 1320. Google Scholar 25 : Radical prostatectomy versus watchful waiting in early prostate cancer. N Engl J Med2005; 352: 1977. Google Scholar 26 : Imaging prostate cancer. Radiol Clin North Am2000; 38: 59. Google Scholar 27 : Magnetic resonance imaging of thermal coagulation effects in a phantom for calibrating thermal therapy devices. Med Phys2000; 27: 1141. Google Scholar 28 : Low-cost phantom for stereotactic breast biopsy training. AJR Am J Roentgenol2006; 187: 972. Google Scholar 29 : CT-guided procedures: evaluation of a phantom system to teach accurate needle placement. Clin Radiol2007; 62: 166. Google Scholar 30 : A training simulator for sentinel node biopsy in breast cancer: a new standard. Eur J Surg Oncol2005; 31: 134. Google Scholar © 2010 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 184Issue 1July 2010Page: 352-357 Advertisement Copyright & Permissions© 2010 by American Urological Association Education and Research, Inc.Keywordsprostateanatomyprostatic neoplasmsphantoms, imagingAcknowledgmentsProf. Brian C. Wilson, Division of Biophysics and Imaging, Ontario Cancer Institute, University of Toronto provided assistance. Laser and laser fibers were provided by Visualase, Inc., Houston, Texas. Patent US 12/457,707 has been filed on the phantom (UL, RAW, MSS and JT).MetricsAuthor Information Uri Lindner Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Nathan Lawrentschuk Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Robert A. Weersink Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Orit Raz Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Eugen Hlasny Joint Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Marshall S. Sussman Joint Department of Medical Imaging, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Sean R. Davidson Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Mark R. Gertner Division of Biophysics and Bioimaging, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author John Trachtenberg Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada More articles by this author Expand All Advertisement PDF downloadLoading ...