Development and validation of high fidelity, patient specific, kidney phantoms for surgical rehearsals

多个中心已经应用3D打印来创建根据患者的 供治疗小组用于术前计划的成像。而目前的做法是 对于外科手术计划来说，现有的打印聚合物都不具备复制组织的能力 允许解剖、止血和缝合的特性。这项建议的重点是开发一种 真正身临其境的、逼真的外科医生模拟平台，从而增加了 技能从排练转移到现场案例。该项目将开发和验证技术 结合图像分割、3D打印和水凝胶成型技术，制作出逼真的、 功能和解剖学上准确的患者特定器官模型将被利用 作为肾癌手术的术前排练平台。我们的基本假设是 通过为外科医生提供高保真、特定于患者的模拟平台，他们可以在其中 视觉和物理交互，他们将能够计划并随后排练患者的程序 充分的浸入，以便执行实际的过程会感觉熟悉，并可以使用 自信和精确度。证明这一假设将集中在三个基本方面，包括1) 确定将复制实质物理特性的水凝胶聚合物规格 身体肾组织和肾血管。测试包括无侧限压缩， 压痕和单轴拉伸强度测试。基于逆有限元的双参数优化 单元模型(有限元分析)将能够确定杨氏模量(E)和泊松比(ν 每个单独的肾脏组件，2)确保所制造的肾脏的解剖准确性 通过比较患者特定肾脏水凝胶与患者原始水凝胶的解剖准确性来实现幻影 成像。扫描和分割模型将生成重复的计算机设计 患者的成像可以与患者的原始计算机设计重叠，该计算机设计是从他们的 医学成像以提供每个结构(实质、肿瘤、动脉、 静脉和泌尿系统)。在实现这头两个目标时，我们将有能力创造成本- 有效的特定于患者的肾脏模型，准确地代表了解剖、物理、功能 (出血)和每个患者的放射学特征。结合了重要的周围器官 将在一个身临其境的模拟平台内复制肾癌手术的所有元素。 最后，我们的第三个目标是评估针对患者的外科手术的可行性、现实性和有效性。 肾癌手术预演环境的研究--I)专家主观手术现实主义 泌尿科医生，以及ii)产生有效的手术性能指标的能力(失血量，缺血时间， 肿瘤大小和肿瘤边缘)，与同一患者的活体手术呈正相关。

Multiple centers have applied 3D printing to create physical models designed from patients' imaging to be utilized by the treating team for preoperative planning. While the current practice is adequate for surgical planning, none of the available printed polymers have the ability to reproduce tissue properties permitting dissection, hemostasis and suturing. The emphasis of this proposal is to develop a truly immersive, realistic simulation platform for practicing surgeons, thus increasing the likelihood of skills transfer from the rehearsal to the live case. This project will develop and validate the technique of combining image segmentation, 3D printing and hydrogel molding technologies to fabricate realistic, functional and anatomically accurate patient-specific organ phantoms from patients' imaging to be utilized as a preoperative surgical rehearsal platform for renal cancer surgeries. Our underlying hypothesis is that by providing surgeons with a high-fidelity, patient-specific, simulation platform in which they can visually and physically interact, they will be able to plan and then rehearse a patient's procedure with sufficient immersion so that performing the actual procedure will feel familiar and can be performed with confidence and precision. Proving this hypothesis will focus on three essential aspects including 1) determining hydrogel polymer specifications that would replicate the physical properties of parenchymal cadaveric kidney tissue as well as renal vasculature. Tests include an unconfined compression, indentation and uniaxial tensile strength testing. Dual parameter optimization using an inverse finite element model (FEA) will enable determination of both Young's modulus (E) and Poisson's ratio (ν) for each individual kidney component, 2) ensuring the anatomical accuracy of the fabricated kidney phantoms by comparing the anatomical accuracy of patient-specific kidney hydrogels to patients' original imaging. Scanning and segmentation of the models will generate a duplicate computer design of the patient's imaging that can be overlaid with the patient's original computer design generated from their medical imaging to provide a quantitative difference error for each structure (parenchyma, tumor, arterial, venous and urinary systems). In achieving these first two aims we will have the capability to create cost- effective patient-specific kidney phantoms that accurately represent the anatomical, physical, functional (bleeding) and radiological properties of each patient. Incorporating the essential surrounding organs would replicate all elements of kidney cancer surgery within a single immersive simulation platform. Finally, our third aim will be to assess the feasibility, realism and validity of our patient-specific surgical rehearsal environment for use in kidney cancer surgery by study of i) subjective surgical realism by expert urologists, and ii) ability to generate valid metrics of operative performance (blood loss, ischemia time, tumor size and tumor margins) that positively correlate to live surgery for the same patient .