Surgical Oncology, Urology Division, University Health Network, University of Toronto, Toronto, Ontario, Canada.
J Urol. 2010 Jul;184(1):352-7. doi: 10.1016/j.juro.2010.03.001. Epub 2010 May 20.
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.
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.
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.
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.
激光的焦点治疗作为前列腺癌治疗的替代策略正在出现。然而，据我们所知，目前还没有可用于测试成像和消融技术的解剖学正确模型。动物模型存在伦理、解剖和成本方面的挑战。我们设计并验证了一种廉价但解剖结构正确的前列腺模型，该模型包含肿瘤、直肠和尿道，可用于模拟和实验性磁共振引导的焦点干预。我们的次要目的是使用其他成像方式评估该模型。
该模型由弹道凝胶制成，包括带有尿道、肿瘤、会阴和直肠的 80 克前列腺。加入钆使凝胶在磁共振成像中可见。为了模拟肿瘤，将形状不规则的 5 立方厘米凝固凝胶插入前列腺模型中。使用磁共振、计算机断层扫描和经直肠超声对模型进行评估。通过间质放置激光光纤进行热消融。进行磁共振测温以记录热消融过程中的实时组织温度。
在测试的所有模式下，该模型模拟了人体前列腺解剖结构。可凝固凝胶肿瘤使我们能够产生焦点热损伤。该模型具有与体内特性相当的磁共振成像特性，允许准确评估消融区域并进行磁共振测温。
该模型是一种有用的工具，可用于使用多种成像方式测试前列腺癌热焦点消融的不同方面，特别是磁共振成像。它价格低廉，易于构建，可被视为一种有价值的模型，可用于培训和教授焦点治疗。
