VASCULAR BUBBLE GENERATION FOR DIAGNOSIS AND THERAPY

从预期更安全的、非常短的、高振幅的声脉冲中成功产生可成像的微泡，增加了诊断的可能性，以及这里讨论的血管内气泡产生的治疗用途。此外，该项目在动脉血液中产生具有所需特性的微泡的声学方法的基础研究以及与广泛的医学超声应用相关的潜在生物效应的研究中占有重要的组成部分。这种基础与应用相结合的方法与我们作为大型学术和临床医学中心的基础与临床医学超声科学研究小组的优势是一致的。将研究来自环境气体（袋）的气泡血液中的声学产生以及全氟碳液滴的汽化，同时注意控制相变、大小和溶解的物理因素。实验研究将评估灌注和梗死的大小，气泡的数量和它们的寿命范围内相关的应用。大脑和视网膜被选为主要的生物效应研究部位，因为它们是最敏感的部位，具有诊断和治疗的潜力。除了目前正在解决的短时间、选择性造影剂生产之外，将通过在颈动脉中引入和产生的气泡，在大脑中评估使用气泡作为点目标来纠正超声束畸变。成功将提供非常高分辨率的超声成像的可能性，经颅和其他区域可获得超声。然后，血流阻断治疗将被开发和评估。几厘米组织区域的梗死将通过治疗体积中的气泡产生和可识别的供应血管闭塞来完成。与传统的血管造影和手术以及类似的CT和MR技术相比，预计这种治疗将更快、更便宜和/或侵入性更小。

Successful generation of imageable microbubbles from what are expected to be much safer, very short, high amplitude acoustic pulses has increased the possibility of diagnostic, as well as therapeutic uses intravascular bubble generation addressed here. In addition, this project maintains a strong component of basic studies of methods of acoustic generation of microbubbles of desired properties in arterial blood, as well as studies of potential bioeffects relevant to a wide range of applications of medical ultrasound. This combined basic and applied approach is consistent with our strengths as a combined basic and clinical medical ultrasound science research group in a large academic and clinical medical center. Acoustic production in the blood of Bubbles from Ambient Gases (BAGs) and by vaporization of perfluorocarbon droplets will be pursued, with attention to physical factors controlling phase transition, size and dissolution. Experimental studies will evaluate the perfusion and infarction effects of size, number of bubbles and their longevity over ranges relevant to the proposed applications. The brain, and retina are chosen as the primary bioeffects study sites because those are among the most sensitive sites and offer diagnostic and therapeutic potential. Moving beyond the short, selective contrast bolus production being addressed at present, use of bubbles as point targets for correction of ultrasound beam distortions will be evaluated in the brain from bubbles introduced and generated in the carotid artery. Success will offer the possibility of very high resolution ultrasound imaging transcranially and in other areas accessible to ultrasound. Then flow occlusion for therapy will be developed and evaluated. Infarction of several centimeter tissue regions will be accomplished by bubble generation both in the treated volume and by occlusion of identifiable supply vessels. It is expected that this treatment will be faster, less expensive and/or less invasive than conventional angiography and surgery and comparable CT and MR techniques.