Magnetic Resonance Image Guided Transurethral Ultrasound Prostate Ablation: A Preclinical Safety and Feasibility Study with 28-Day Followup

No AccessJournal of UrologyInvestigative Urology1 May 2015Magnetic Resonance Image Guided Transurethral Ultrasound Prostate Ablation: A Preclinical Safety and Feasibility Study with 28-Day Followup Mathieu Burtnyk, Tracy Hill, Heather Cadieux-Pitre, and Ian Welch Mathieu BurtnykMathieu Burtnyk , Tracy HillTracy Hill , Heather Cadieux-PitreHeather Cadieux-Pitre , and Ian WelchIan Welch View All Author Informationhttps://doi.org/10.1016/j.juro.2014.11.089AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: We determine the safety and feasibility of magnetic resonance image guided transurethral ultrasound prostate ablation using active temperature feedback control in a preclinical canine model with 28-day followup. Materials and Methods: After a long acclimatization period we performed ultrasound treatment in 8 subjects using the magnetic resonance image guided TULSA-PRO™ transurethral ultrasound prostate ablation system. Comprehensive examinations and observations were done before and throughout the 28-day followup, including assessment of clinically significant treatment related adverse events. In addition to gross pathology evaluation, extensive histopathological analysis was done to assess cell kill inside and outside the prostate. We evaluated prostate conformal heating by comparing the spatial difference between the treatment plan and the 55C isotherm measured on magnetic resonance imaging thermometry acquired during treatment. These findings were confirmed on contrast enhanced magnetic resonance imaging immediately after treatment and at 28 days. Results: Clinically there were no adverse events in any of the 8 subjects throughout the 28-day followup. All subjects had normal urinary and bowel function. Gross necropsy and histology confirmed that the intended thermal cell kill was confined to the prostate. No surrounding tissue was damaged, including the rectum and the external urinary sphincter. Conformal heating was achieved with an average −0.9 mm accuracy and 0.9 mm precision. Contrast enhanced magnetic resonance imaging and histological analysis confirmed tissue ablation in targeted areas of the prostate. Urethral tissue was spared from thermal damage. Conclusions: Magnetic resonance image guided transurethral ultrasound is a safe, feasible procedure for accurate and precise conformal thermal ablation of prostate tissue, as demonstrated in a preclinical model with 28-day followup. References 1 : Estimates of worldwide burden of cancer in 2008: GLOBOCAN 2008. Int J Cancer2010; 127: 2893. Google Scholar 2 : Five-year outcomes after prostatectomy or radiotherapy for prostate cancer: the prostate cancer outcomes study. 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Link, Google Scholar © 2015 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetailsCited byKlotz L, Pavlovich C, Chin J, Hatiboglu G, Koch M, Penson D, Raman S, Oto A, Fütterer J, Serrallach M, Relle J, Lotan Y, Heidenreich A, Bonekamp D, Haider M, Tirkes T, Arora S, Macura K, Costa D, Persigehl T, Pantuck A, Bomers J, Burtnyk M, Staruch R and Eggener S (2020) Magnetic Resonance Imaging-Guided Transurethral Ultrasound Ablation of Prostate CancerJournal of Urology, VOL. 205, NO. 3, (769-779), Online publication date: 1-Mar-2021.Ramsay E, Mougenot C, Staruch R, Boyes A, Kazem M, Bronskill M, Foster H, Sugar L, Haider M, Klotz L and Chopra R (2016) Evaluation of Focal Ablation of Magnetic Resonance Imaging Defined Prostate Cancer Using Magnetic Resonance Imaging Controlled Transurethral Ultrasound Therapy with Prostatectomy as the Reference StandardJournal of Urology, VOL. 197, NO. 1, (255-261), Online publication date: 1-Jan-2017. Volume 193Issue 5May 2015Page: 1669-1675 Advertisement Copyright & Permissions© 2015 by American Urological Association Education and Research, Inc.Keywordsinterventionalequipment and suppliesprostatic neoplasmsmagnetic resonance imagingdogshigh intensity focused ultrasound ablationMetricsAuthor Information Mathieu Burtnyk Financial interest and/or other relationship with Profound Medical. More articles by this author Tracy Hill More articles by this author Heather Cadieux-Pitre More articles by this author Ian Welch More articles by this author Expand All Advertisement PDF downloadLoading ...