Ultrasound-Guided Robotic Needle Steering for Ablation of Liver Cancer

描述（由申请人提供）：2014年美国预计将诊断出33190例原发性肝癌新病例和更多的肝脏转移性癌症新病例。根除这些肿瘤可以提高病人的存活率。经皮射频消融术（RFA）通过热损伤杀死肿瘤，是一种微创治疗，适用于许多不适合手术切除的患者，特别是那些具有特定肿瘤类型、位置或大小的患者；肝功能差；或者其他合并症。然而，技术限制阻碍了RFA作为消除肝脏肿瘤的手段的广泛采用。肝脏某些部位的肿瘤无法进入，因为目前RFA电极采用的直线路径将穿过脉管系统、肺或其他敏感结构。大肿瘤需要多次电极插入；在患有晚期肝病或严重合并症的患者中，每次穿刺肝包膜的出血风险都会增加。这项工作的长期目标是使用机器人辅助的针导向，显著提高经皮肝脏RFA手术的可及性、准确性和精度。以下具体目标将促进该技术的发展并证明其可行性，作为临床应用的途径：具体目标1：优化基于超声的高弯曲针头定位和机器人针头转向的闭环控制。具体目标2：开发交互式用户控制界面，实现远程操作针转向干预。具体目标3：设计一种用于经皮肝脏射频消融的临床机器人辅助针控系统，并在离体肝脏模型中进行验证。具体目标4：验证超声引导下的猪肝针导向系统。针导向技术可以使高度灵活的针或导丝沿着受控的、弯曲的、3D的路径穿过组织。因此，针头可以被主动引导，以获取无法通过直线路径到达的肿瘤，并且随着针头向肿瘤推进，可以纠正与期望路径的意外偏差。适合体内实验的功能性针导向系统必须兼容广泛可用的医学成像（这里，超声成像），具有提供治疗的能力（这里，通过使用可操纵针电极的RFA），以及适当的用户界面，包括可视化和人在环远程操作。这项技术可以将RFA的生存优势扩展到那些可能没有良好治疗选择的患者，并且从长远来看，可用于准确放置诊断设备和治疗其他器官的疾病。

DESCRIPTION (provided by applicant): An estimated 33,190 new cases of primary liver cancer and an even larger number of new cases of metastatic cancer to the liver will be diagnosed in the United States in 2014. Eradicating those tumors improves patient survival. Percutaneous radiofrequency ablation (RFA), which kills tumors via thermal damage, is a minimally invasive treatment appropriate for the many patients who are not eligible for surgical resection, particularly those with certain tumor type, location, or size; poor liver function; or oher comorbidities. However, technical limitations have precluded broader adoption of RFA as a means of eliminating liver tumors. Tumors in some portions of the liver cannot be accessed because the straight paths currently taken by RFA electrodes would traverse vasculature, lung, or other sensitive structures. Large tumors require multiple electrode insertions; the increased bleeding risk with each puncture through the liver capsule can be too great in patients with advanced liver disease or severe comorbidities. The long-term goal of this work is to significantly improve access, accuracy, and precision during percutaneous liver RFA procedures using robot-assisted needle steering. The following specific aims will enable the development of this technology and demonstrate feasibility, as a path to clinical adoption: Specific Aim 1: Optimize ultrasound-based localization of highly curved needles and closed-loop control of robotic needle steering. Specific Aim 2: Develop an interactive user control interface and enable teleoperated needle steering intervention. Specific Aim 3: Design a clinical robot-assisted needle steering system for percutaneous liver RFA, validated in an ex vivo liver model. Specific Aim 4: Validate the ultrasound-guided needle steering system in vivo in porcine liver. Needle steering enables the insertion of highly flexible needles or guidewires along controlled, curved, 3D paths through tissue. Thus, the needle can be actively steered to acquire tumors not accessible by a straight- line path, and unexpected deviations from the desired path can be corrected as the needle advances toward the tumor. A functional needle steering system appropriate for in vivo experimentation must be compatible with widely available medical imaging (here, ultrasound imaging), have the ability to deliver treatment (here, RFA through the use of a steerable needle electrode), and an appropriate user interface including visualization and human-in-the-loop teleoperation. This technology could extend the survival advantages of RFA to patients who may otherwise not have good treatment options, and in the long term, be used for accurate placement of diagnostic devices and treatment of diseases in other organs.