Steerable Catheters using Micro-fabricated Dielectric Elastomer Actuators

导管是广泛用于进入体腔、导管或血管的医疗设备。根据材料和制造方法的不同，导管有心血管、泌尿、胃肠道、神经血管和眼科的应用。特别是对于血管干预，将导管与导丝串联导航到所需位置是该过程中最耗时和最微妙的部分。根据干预的类型，将导管和导丝相互滑动并在患者体外重塑导丝尖端的过程可能需要几分钟或几个小时。治疗的任何延误都可能对患者的预后非常不利，特别是当介入医生的目的是进行血栓切除术（即从大脑阻塞的血管中取出血栓）时；到达血块的时间很关键。医学和工程研究人员通常采用相同的方法来减少导航时间：使导管或导丝可操纵。方法包括拉线机制，磁控制尖端，和智能材料，驱动弯曲尖端。这些系统的限制分为两类：不利的扩展或繁琐的实现。我们提出了一种新的微加工范例，以制造介电弹性体作为人造肌肉，可以附着在微导管上，使其能够在弯曲和狭窄的血管中转向。从根本上说，这个项目跨越了多个学科：利用制造和材料工程来创造机器人元件，为介入放射学的医疗设备提供动力。预计该技术将代表对用于心血管、泌尿、胃肠道、神经血管和眼科应用的可操纵导管/微导管的重要增强。市场评估的一个关键问题将是确认在所需规模和功能方面将从主题技术中获益最多的医疗设备/医疗程序。

Catheters are medical devices widely used to access body cavities, ducts, or vessels. Depending on the material and manufacturing method, catheters have cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic applications. Particularly for vascular interventions, the navigation of a catheter in tandem with a guidewire to the desired location is the most time consuming and delicate part of the process. The process of sliding catheters and guidewires past each other and reshaping the tip of the wire outside the patient's body can take minutes or up to hours, depending on the type of intervention. Any delays in treatment can be very detrimental to patient outcomes, especially where the interventionist aims to perform a thrombectomy (i.e., remove a clot from a blocked vessel in the brain); the time to reach the clot is critical. Medical and engineering researchers have generally taken the same approach to reduce navigation time: make the catheter or guide wire steerable. Approaches include pull wire mechanisms, magnetic controlled tips, and smart materials that actuate to bend the tip. The limitations of these systems fall into two categories: unfavorable scaling or cumbersome implementation. We propose a new microfabrication paradigm to create dielectric elastomers as artificial muscles that can be attached to micro-catheters to enable steering in tortuous and narrow vessels. Fundamentally the project spans disciplines: using manufacturing and materials engineering to create robotic elements to power medical devices for interventional radiology. It is anticipated that the technology will represent an important enhancement to steerable catheters/micro-catheters that are used for cardiovascular, urological, gastrointestinal, neurovascular, and ophthalmic applications. A key question for the market assessment will be to confirm the medical devices/medical procedures that would benefit the most from the subject technology in terms of desired scale and features.