Monitoring of Breast Neoadjuvant Therapy by Thermo- and Photo- Acoustic Tomograph

描述（由申请人提供）：我们建议采用临床超声成像系统开发高分辨率微波诱导热声断层扫描（TAT）和激光诱导光声断层扫描（PAT）。这三种兼容的成像模式共享相同的超声检测系统，并提供互补的对比。长期目标是为乳腺新辅助治疗（化疗或激素治疗）的早期功能监测提供临床工具。许多乳腺癌患者接受新辅助治疗以减小肿瘤大小并使保乳治疗成为可能。一种灵敏的检测治疗反应的方法可能允许治疗的早期调整，从而产生更好的结果。此外，如果药物选择没有产生反应，及时和早期改变药物方案将减轻患者在等待治疗反应期间遭受的一些不必要的发病率。TAT/PAT是基于将短脉冲电磁能量安全沉积到乳房中产生热声/光声波。每一个微波/激光脉冲都会使温度迅速上升10毫度。利用超声换能器阵列检测热弹性膨胀引起的超声发射，然后重建图像。TAT和PAT旨在克服纯微波和纯光学成像的空间分辨率差，同时保持高对比度。在空间分辨率上，纯微波成像由于微波波长较长，有较强的衍射，而纯光学成像在组织中有较强的光散射。超声波可以在组织中传播，散射相对较低，因此可以提供良好的空间分辨率。申请人已经展示了高分辨率（低至0.5毫米）的无斑点图像。我们假设TAT和PAT的联合对比以及超声检查可以准确预测乳房新辅助治疗的反应。TAT主要测量水/钠对比，而PAT测量血容量和血氧对比。具体目的如下：1。TAT/PAT乳腺成像系统的开发。2. 飞利浦临床超声成像系统的改造。3. 幻影研究：用组织幻影验证所提出的成像系统。4. 体内研究：首先，对少量人体乳房进行成像，微调成像系统。其次，对人体乳房进行成像并进行回顾性统计分析。第三，对人体乳房进行成像，并对成像系统进行前瞻性验证。公共卫生相关性：成像技术使生物医学领域的许多发现成为可能，并提供了疾病的早期诊断。功能成像不仅可以检测组织结构，还可以检测组织功能，这将在生物医学领域产生更大的影响。提出的热声和光声成像技术可以潜在地为乳房新辅助治疗（化疗或激素治疗）的早期功能监测提供临床工具。

DESCRIPTION (provided by applicant): We propose to develop high-resolution microwave-induced thermoacoustic tomography (TAT) and laser-induced photoacoustic tomography (PAT) by adapting a clinical ultrasound imaging system. These three compatible imaging modalities share the same ultrasound detection system and provide complementary contrasts. The long-term goal is to provide a clinical tool for the early functional monitoring of breast neoadjuvant therapy (chemo- or hormone therapy). Many breast cancer patients receive neoadjuvant treatment to reduce tumor size and enable breast conserving therapy that would otherwise have not been possible. A sensitive method of detecting response to therapy might allow earlier adjustments in treatment, and thus, result in better outcomes. Furthermore, if drug choices are not resulting in response, prompt and early changes in drug regimens will alleviate some of the unnecessary morbidity that patients suffer during treatment while awaiting response to therapy. TAT/PAT is based on the generation of thermoacoustic/photoacoustic waves by the safe deposition of short-pulsed electromagnetic energy into the breast. Each microwave/laser pulse causes a rapid temperature rise on the order of 10 millidegrees. The ultrasonic emission due to thermoelastic expansion is detected with an array of ultrasonic transducers and then used to reconstruct an image. TAT and PAT are designed to overcome the poor spatial resolution of pure microwave and pure optical imaging yet to retain the high contrasts. In terms of spatial resolution, pure microwave imaging suffers from strong diffraction due to long microwave wavelength, whereas pure optical imaging suffers from strong optical scattering in tissue. Ultrasonic waves can propagate in tissue with relatively low scattering and can therefore provide good spatial resolution. The applicants have demonstrated speckle-free images at high resolution (as low as 0.5 mm). We hypothesize that the combined contrasts from TAT and PAT as well as ultrasonography can accurately predict breast neoadjuvant therapeutic response. TAT measures dominantly water/sodium contrast, whereas PAT measures blood volume and blood oxygenation contrasts. The specific aims are as follows: 1. Development of the TAT/PAT breast imaging system. 2. Adaptation of a Philips clinical ultrasound imaging system. 3. Phantom study: Validate the proposed imaging system with tissue phantoms. 4. In vivo study: First, image a small number of human breasts to fine tune the imaging system. Second, image human breasts and perform statistical analysis retrospectively. Third, image human breasts and validate the imaging system prospectively. PUBLIC HEALTH RELEVANCE: Imaging technologies have enabled numerous discoveries in biomedicine and provided early diagnosis of disease. Functional imaging that detects not only tissue structure but also tissue function will make even greater impact in biomedicine. The proposed thermoacoustic and photoacoustic imaging technologies can potentially provide a clinical tool for the early functional monitoring of breast neoadjuvant therapy (chemo- or hormone therapy).