Biomechanical Modeling for Steerable Needles

描述(由申请人提供)： 这项工作的长期目标是利用斜面针尖弯曲的效果，为经皮疗法提供准确、灵活的靶向。针和组织建模方面的新成果，与机器人运动建模相结合，将促进在软组织内操纵柔性针的新模型、硬件、控制和规划技术。利用机器人领域的路径规划、控制和运动学结果，我们计划演示适当设计的针可以引导组织到达指定的3-D目标。更令人信服的是，我们提出的方法将允许针被引导到以前无法接触到的身体位置，从而实现新的微创手术。 针控制的第一步是获得一个准确的模型。因此，这一探索性/发展性应用的具体目标是了解和模拟针运动的生物力学。这是一项高风险的活动，因为之前还没有成功地模拟软组织中柔性针的3-D路径的工作。这项工作具有很高的影响力，因为精确的3-D针建模可以用于(1)改进靶向，从而增强许多经皮疗法和诊断方法的性能，(2)规划绕过障碍物的针路径，以及(3)开发用于医生培训和患者特定规划的逼真模拟器。研究人员将与医生合作者密切合作，研究与提高医疗保健质量相关的针头插入情景。 具体目标如下：(1)建立并验证未变形组织穿刺针的确定性生物力学模型。所需尖端的弯曲将是组织属性、针属性和输入参数的函数。在体模组织上改进和测试该模型。选择便于转向的针头设计参数。(2)进一步细化Aim 1的模型，考虑约束和输入不确定性的影响，建立未变形组织穿针的随机生物力学模型。计算一组给定输入的可能针尖位置的空间，并确定获取特定目标的概率。(3)进一步改进AIMS 1和AIMS 2的模型，以同时考虑组织变形和非均匀组织特性的影响。一个特别的挑战是开发同时处理针和组织变形的新建模技术。

DESCRIPTION (provided by applicant): The long term goal of this work is to harness the effect of bevel tip needle bending to provide accurate, dexterous targeting for percutaneous therapies. New results in needle and tissue modeling, combined with robot motion modeling, will facilitate new models, hardware, control, and planning techniques for steering flexible needles inside soft tissue. Using path planning, control, and kinematics results from the field of robotics, we plan to demonstrate that an appropriately designed needle can be steered through tissue to reach a specified 3-D target. Even more compelling is that the methods we propose will allow needles to be steered to previously inaccessible locations in the body, enabling new minimally invasive procedures. The first step in needle control is to obtain an accurate model. Thus, the specific goals of this exploratory/developmental application are to under stand and model the biomechanics of needle motion. This is a high-risk activity because there has been no previous work to successfully model the 3-D path of flexible needles through soft tissue. The work is high impact because accurate 3-D needle modeling can be used to (1) improve targeting, thus enhancing the performance of many percutaneous therapies and diagnostic methods, (2) plan needle paths that steer around obstacles, and (3) develop realistic simulators for physician training and patient-specific planning. Working closely with physician collaborators, the investigators will study needle insertion scenarios that are relevant to improving the quality of health care. The specific aims are as follows: (1) Develop and validate a deterministic biomechanical model of needle insertion through un deformed tissue. The bending of the need le tip will be a function of tissue properties, needle properties and input parameters. Refine and test the model on phantom tissues. Select needle design parameters that facilitate steering. (2) Further refine the model of Aim 1 to include the effects of constraint and input uncertainties, generating a stochastic biomechanical model of needle insertion through undeformed tissue. Compute the space of possible needle tip positions for a given set of inputs and determine the probability of acquiring specific targets. (3) Further refine the models of Aims 1 and 2 to include the effects of both tissue deformation and inhomogeneous tissue properties. A particular challenge is the development of new modeling techniques that simultaneously handle needle and tissue deformation.