Cavernosal nerve functionality evaluation after magnetic resonance imaging-guided transurethral ultrasound treatment of the prostate

• 作者: Ambereen Yousuf Ari Partanen Aria Razmaria Aytekin Oto Christina L Sammet Craig Wardrip Emily V Ward Gregory Karczmar Keyvan Farahani Marek Niekrasz Shunmugavelu Sokka Steffen Sammet Tatjana Antic
• 来源期刊: 世界放射学杂志：英文版（电子版）
• 学科: 医学
• 关键词: ULTRASOUND THERAPY Thermal tissue ablation PROSTATE Magnetic resonance imaging GUIDED THERAPY INTRA-OPERATIVE Histology Validation
• 年，卷（期）: sjfsxzzywbdzb_2015,（12）
• 页码范围: 521-530
• 页数: 10页
• 分类号: R737.25

摘要

AIM: To evaluate the feasibility of using therapeutic ultrasound as an alternative treatment option for organconfined prostate cancer. METHODS: In this study, a trans-urethral therapeutic ultrasound applicator in combination with 3T magnetic resonance imaging(MRI) guidance was used for realtime multi-planar MRI-based temperature monitoring and temperature feedback control of prostatic tissue thermal ablation in vivo. We evaluated the feasibility and safety of MRI-guided trans-urethral ultrasound to effectively and accurately ablate prostate tissue while minimizing the damage to surrounding tissues in eight canine prostates. MRI was used to plan sonications, monitor temperature changes during therapy, and to evaluate treatment outcome. Real-time temperature and thermal dose maps were calculated using the proton resonance frequency shift technique and were displayed as two-dimensional color-coded overlays on top of the anatomical images. After ultrasound treatment, an evaluation of the integrity of cavernosal nerves was performed during prostatectomy with a nerve stimulator that measured tumescence response quantitatively and indicated intact cavernous nerve functionality. Planned sonication volumes were visually correlated to MRI ablation volumes and corresponding histo-pathological sections after prostatectomy. RESULTS: A total of 16 sonications were performed in 8 canines. MR images acquired before ultrasound treatment were used to localize the prostate and to prescribe sonication targets in all canines. Temperature elevations corresponded within 1 degree of the targeted sonication angle, as well as with the width and length of the active transducer elements. The ultrasound treatment procedures were automatically interrupted when the temperature in the target zone reached 56 ℃. In all canines erectile responses were evaluated with a cavernous nerve stimulator post-treatment and showed a tumescence response after stimulation with an electric current. These results indicated intact cavernous nerve functionality.