Exploration of Ultrasound-Activated Bubbles as a Switchable MRI Contrast Agent

微气泡和纳米气泡已被用于超声成像，以突出病变组织，特别是 肿瘤，以帮助医生发现疾病。这些气泡还可以填充治疗药物，以及 当它们位于所需位置时，使用超声波能量弹出。虽然这些基于气泡的对比 药物使肿瘤更容易在超声图像上看到，但识别解剖结构仍然是一项挑战 超声图像中的结构，这是由于这种方式的软组织对比度相对较差。超音波 成像在成像所需的较高频率上的穿透深度也受到限制，这可能会使 包括身体成像在内的一些应用程序具有挑战性。另一方面，磁共振成像(MRI) 能够以精致的对比度和完整的覆盖范围对肝脏等大型器官进行成像。的缺点是 MRI的低敏感性使微小癌变的检测具有挑战性，而治疗 磁共振成像不能非侵袭性地启动肿瘤。 该项目的目标是探索使用超声波激活的纳米气泡作为可切换的磁共振成像对比剂。 能够快速有效地检测和治疗转移性疾病的试剂。在这里， MRI上存在微气泡和/或纳米气泡，无论是否施加超声能量 信号将被测试。我们假设，仅仅是小气泡的存在对磁共振成像的影响不大。 信号，但通过施加超声能量，MRI信号可以在快速的时间尺度上显著改变 向泡沫致敬。将重新研究气泡的配方，以最大限度地提高它们改变周围环境的能力 磁场从而影响MRI信号，并将各种形式的MRI数据采集进行测试，以启用 气泡的快速定位。请注意，这种造影剂的可切换性质是真正独特的 MRI，将对如何收集MRI数据产生深远影响，为创新打开大门 获取数据和生成图像的策略。这一探索性项目将为测试 这种新的可切换的体内MRI造影剂用于可靠地检测和有效治疗小转移瘤 肿瘤。请注意，该团队包括一位超声造影剂纳米气泡设计的专家，一位核磁共振 以开发创新的数据收集和图像重建方法而闻名的物理学家，以及第二位 核磁共振物理学家，既有结合核磁共振/超声的经验，又能使用所需的工具 完成这项工作。

Micro- and nanobubbles have been used in ultrasound imaging to highlight diseased tissue, specifically tumors, to aid physicians in detecting disease. These bubbles can also be filled with therapeutic drugs, and popped using ultrasound energy when they are at the desired location. While these bubble-based contrast agents make tumors easier to see on ultrasound images, it can still be challenging to recognize anatomical structures in ultrasound images due to the relatively poor soft tissue contrast of this modality. Ultrasound imaging is also limited in penetration depth at the higher frequencies needed for imaging, which can make some applications including body imaging challenging. On the other hand, Magnetic Resonance Imaging (MRI) is able to image large organs such as the liver with exquisite contrast and complete coverage. The drawback of MRI is that its low sensitivity makes the detection of small cancerous lesions challenging, and treatment of the tumor cannot be initiated non-invasively with MRI. The goal of this project is to explore the use of ultrasound-activated nanobubbles as a switchable MRI contrast agent to enable the rapid and effective detection and treatment of metastatic disease. Here, the effect of the presence of micro- and/or nanobubbles, both with and without the application of ultrasound energy, on the MRI signal will be tested. We hypothesize that the mere presence of small bubbles will have little impact on the MRI signal, but that the MRI signal can be dramatically altered on a rapid timescale by applying ultrasound energy to the bubbles. The formulation of the bubbles will be revisited to maximize their ability to alter the surrounding magnetic field and thus affect the MRI signal, and various forms of MRI data collection will be tested to enable rapid localization of the bubbles. Note that the switchable nature of this contrast agent, which is truly unique in MRI, will have a profound impact on how the MRI data can be collected, opening the door for innovative strategies for acquiring data and generating images. This exploratory project will pave the way for testing of this novel switchable MRI contrast agent in vivo for robust detection and efficient treatment of small metastatic tumors. Note that the team includes an expert on nanobubble design for ultrasound contrast agents, an MRI physicist renowned for developing innovative data collection and image reconstruction methods, and a second MRI physicist who has both the experience in combined MRI/ultrasound and access to the tools needed to perform this work.