Ultrasound Ablation on Bone Cancer Under CT Fluoroscopy

描述（由申请人提供）：转移性骨癌和多发性骨髓瘤在美国每年影响超过60万人，并导致进行性骨破坏，导致严重疼痛、骨折和无法行走。患者通常表现为继发于骨质受累的失能性疼痛，伴有或不伴有椎体塌陷，以及脊髓和/或神经根压迫，通常导致截瘫和四肢瘫痪。常规治疗包括卧床休息、支具、抗炎或麻醉性镇痛药物和放射治疗。这些保守治疗（放射治疗除外）与治疗骨质疏松性压缩性骨折没有什么不同，并且与相同类型的并发症有关，即，肺不张和肺炎、深静脉血栓形成和肺栓塞。并非所有患者都可以选择手术，但在适应症下，手术包括重度干预，如椎体次全切除术或椎间融合器置入，术后恢复期较长，预期寿命有限的患者发病率和死亡率较高。此外，多灶性椎体病变是常见的，可能禁忌手术。椎体成形术会影响疼痛症状，并非用于治疗癌症。目前转移性脊柱癌的局部治疗选择不足。假设是，采用与肿瘤大小和形状特异性匹配的高强度组织间超声（HIIU）进行热消融治疗转移性脊柱癌是安全有效的。我们建议开发一种在联合计算机断层扫描（CT）和CT荧光透视（CTF）引导下进行微创适形超声消融的机制。我们的工作表明，这种方法可以提供一个一致的，可靠的，安全的治疗选择，在一个简单的和具有成本效益的方式。我们的方法的独特之处在于能够用单针破坏不对称的靶体积，而不需要将单针放置在病变的中心。在CT/CTF图像引导下，我们插入消融器，相对于靶区定位消融器，然后电子成形能量输出以符合靶区。因此，适度的放置错误可以简单地电子校正。我们还可以烧蚀位于敏感结构附近的困难形状。临床上迫切需要提供一种方法，以集中和安全的方式在这个敏感区域杀死肿瘤，保护脊髓，肿瘤可能已经在脊髓周围造成显著的骨破坏。使能量符合具有清晰限定的边缘场的肿瘤形状的能力是关键的，并且将增加非常显著的临床价值。该项目将开发一个集成的仪器-消融治疗输送系统，在实时定量CT/CTF引导下建立安全准确的经皮HIIU针放置和肿瘤消融，开发适当的临床工作流程，并证明在临床应用中的使用。

DESCRIPTION (provided by applicant): Metastatic bone cancer and multiple myeloma affects over 600,000 people every year in the United States and cause progressive bone destruction that results in severe pain, fractures, and the inability to walk. Patients usually present with incapacitating pain secondary to osseous involvement, with or without vertebral collapse, and to spinal cord and/or nerve roots compression, commonly leading to paraplegia and quadriplegia. Conventional therapy consists of bed rest, bracing, anti-inflammatory, or narcotic analgesic medications, and radiation therapy. These conservative options (except radiation therapy) are not dissimilar from the management of osteoporotic compression fractures and are associated with the same type of complications, i.e., atelectasis and pneumonia, deep venous thrombosis and pulmonary embolism. Surgical options are not possible for all patients, but when indicated, they consist of heavy interventions such as corpectomy or cage placement, with significant postprocedural recovery periods and high morbidity and mortality rates in patients who often have limited life expectancies. In addition, multifocal vertebral lesions are common and may contraindicate surgery. Vertebroplasty affects the pain symptom and was not designed to treat cancer. Current options for local treatment of metastatic spine cancer are insufficient. The hypothesis is that thermal ablation with high intensity interstitial ultrasound (HIIU) specifically matched to the tumor size and shape can be safe and efficacious in the management of metastatic spine cancer. We propose to develop a mechanism to perform minimally invasive conformal ultrasound ablation under combined computer tomography (CT) and CT fluoroscopy (CTF) guidance. Our work indicates that this method may provide a consistent, reliable, and safe treatment option in a simple and cost-efficient manner. The unique aspect of our approach is the ability to destruct an asymmetric target volume with a single needle that does not need to be placed in the center of the lesion. Under CT/CTF image guidance, we insert the ablator, localize the ablator with respect to the target zone, and then electronically shape the energy output to conform the target. Thus moderate placement errors can be simply corrected electronically. We also can ablate difficult shapes located nearby sensitive structures. There is a strong clinical need to deliver a means to kill the tumor in a focused and safe way in this sensitive area, protecting the spinal cord, around which the tumor is likely to have caused significant bone destruction already. The ability to conform the energy to the shape of the tumor with a sharply defined fringe field is critical and would add very significant clinical value. This program will develop an integrated instrumentation - ablative treatment delivery system, establish safe and accurate percutaneous HIIU needle placement and tumor ablation under real-time quantitative CT/CTF guidance, develop appropriate clinical workflow, and demonstrate use in clinical application.