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: 6394752
• 负责人: Charles Alan Cain
• 金额: $ 27.85万
• 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/6394752
• 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（改编自申请人的摘要）：勾选此方法 声空化是可预测的，因此作为一种实用的机制 本研究将探讨无创手术。新颖的方法 准确放置治疗光束并验证手术病灶已被清除 也将进行探索。随着大孔径相控阵的使用 系统和像差校正技术，有可能形成高 优质超声波束围绕并穿过肋骨等障碍物，或 颅骨，具有有吸引力的无创脑部手术或心脏手术的可能性 消融治疗危及生命的心律失常。随着能量的流失 在围绕这些障碍物传播并穿过这些障碍物时，热烧蚀，无需 加热复杂的介入组织是一个困难的提议。然而， 空化，特别是在较低超声频率下运行的阵列， 成为一种令人兴奋的组织消融机制，有待进一步研究。特别是 人们感兴趣的是稳定微泡的潜在用途，通常用作 超声成像造影剂，起到降低空化核的作用 空化阈值并使空间定位可预测。空化现象 过去已被有意避免，因为可重复本地化 消融区域（或手术损伤）一直很困难，主要是由于大 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，手术损伤 通过预先使用造影剂，尺寸和形状变得更加可预测 代理。申请人建议系统地探索对比的作用 影响空化阈值、手术病灶大小和组织学的药物， 坏死区形状和空间定位的可预测性，以及坏死区的作用 造影剂浓度。这样的系统将允许高度可预测的光束 以非侵入方式形成，例如，在肋骨周围形成移动目标， 例如心脏。造影剂也将被探索作为靶向手段 治疗光束并作为验证手术损伤已形成的方法 所需的治疗量。这个应用程序是基于他们的实验 观察到微泡可以被低强度超声波“塌陷” 造成图像中的“较暗”区域，从而形成子病变 在应用手术之前用于光束定位的强度 强度。由于空化引起的病变可能会破坏局部 血管系统，手术坏死的体积不会用造影剂重新灌注 指示病变程度的试剂。申请人将探索对比的使用 代理作为指导、增强和验证手术病变形成的手段 高强度超声波。