HIGH INTENSITY ULTRASOUND FOR NON-INVASIVE SURGERY

用于非侵入性手术的高强度超声波

• 批准号: 6639874
• 负责人: Charles Alan Cain
• 金额: $ 28.88万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-04-01 至 2005-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6639874
• 关键词: surgery; surgery material /equipment; technology /technique development; ultrasound therapy

DESCRIPTION (Adapted from Applicant's Abstract): Check thisWays to make acoustic cavitation predictable, and thus practical as a mechanism for noninvasive surgery, will be explored in this research. Novel ways to accurately place therapy beams and verifying that surgical lesions have been formed will also be explored. With the use of large aperture phased array systems, and aberration correction techniques, it is possible to form high quality ultrasound beams around and through obstructions like ribs, or the skull, with the attractive possibility of noninvasive brain surgery or cardiac ablation for treatment of life threatening arrhythmias. With the loss of energy in propagating around and through such obstructions, thermal ablation, without heating the complex intervening tissue, is a difficult proposition. However, cavitation, particularly from arrays operating at lower ultrasound frequencies, becomes an exciting tissue ablation mechanism for further study. Of particular interest is the potential use of stabilized microbubbles, often used as ultrasound imaging contrast agents, to act as cavitation nuclei lowering cavitation thresholds and making spatial localization predictable. Cavitation has been intentionally avoided in the past because reproducible localization of ablation zones (or surgical lesions) has been difficult mostly due to large unpredictable spatial variations in cavitation thresholds in living tissues. Preliminary experiments with phased array systems suggest that surgical lesion size and shape become more predictable with prior administration of contrast agents. The applicants proposed to systematically explore the role of contrast agents on cavitation thresholds, surgical lesion size and histology, predictability of shape and spatial localization of necrotic zones, and role of contrast agent concentration. Such systems will allow highly predictable beams to be formed non-invasively, for example, around the ribs onto a moving target, e.g. the heart. Contrast agents will also be explored as means for targeting therapy beams and as a way to verify that surgical lesions have been formed in the desired treatment volume. This application is based on their experimental observation that microbubbles can be "collapsed" by low intensity ultrasound causing "darker" areas in the image, thus allowing sub-lesion forming intensities to be used for beam localization prior to application of surgical intensities. Since cavitationally induced lesions will likely destroy the local vasculature, a surgically necrosed volume will not re-perfuse with contrast agent indicating lesion extent. The applicants will explore use of contrast agents as means to guide, enhance, and verify surgical lesion formation with high intensity ultrasound.

描述（改编自申请人摘要）：检查此方法 声空化是可预测的，因此作为一种机制是实用的， 非侵入性手术，将在这项研究中进行探索。新颖的方式来 准确地放置治疗光束，并验证手术损伤已经 也将进行探索。利用大口径相控阵 系统和像差校正技术，有可能形成高的 高质量的超声波束围绕并穿过肋骨等障碍物， 头骨，具有吸引人的可能性，非侵入性脑外科手术或心脏 用于治疗危及生命的心律失常的消融术。随着能量的流失 在围绕和穿过这些障碍物的传播中，热烧蚀， 加热复杂的介入组织是一个困难的问题。然而，在这方面， 空化，特别是来自在较低超声频率下操作的阵列， 成为一种值得进一步研究的令人兴奋的组织消融机制。特别 感兴趣的是稳定的微泡的潜在用途，通常用作 超声成像造影剂，用作降低空化核 空化阈值和使空间定位可预测。空化 在过去一直有意避免，因为 消融区域（或手术损伤）已经很困难，主要是由于大的 活组织中空化阈值的不可预测的空间变化。 相控阵系统的初步实验表明， 尺寸和形状变得更可预测 剂.申请人建议系统地探讨对比的作用 药物对空化阈值、手术损伤大小和组织学的影响， 坏死区的形状和空间定位的可预测性，以及 造影剂浓度。这样的系统将允许高度可预测的光束 为了非侵入性地形成，例如，在移动目标上的肋骨周围， 例如心脏。还将探索造影剂作为靶向手段 治疗光束，并作为一种方式，以验证手术损伤已形成， 所需的治疗体积。这个应用程序是基于他们的实验 观察到微泡可以通过低强度超声"塌陷" 导致图像中的"较暗"区域，从而允许形成亚损伤 在应用外科手术前用于光束定位的强度 强度。由于空化引起的损伤可能会破坏局部 血管系统，手术坏死体积不会用造影剂重新灌注 指示病变程度的药剂。申请人将探索使用对比 作为引导、增强和验证手术损伤形成的手段的试剂， 高强度超声波