Continuous Photoacoustic Monitoring of Neonatal Stroke in Intensive Care Unit

项目概要/摘要 新生儿脑病可由分娩时胎儿缺氧缺血、慢性子宫胎盘炎、 炎症和主要由胎盘血栓移位引起的大脑动脉栓塞。 由于重叠的临床表现，鉴别诊断往往被推迟，直到癫痫发作的发展， MRI可以安全地进行，此时大多数神经保护剂无效。而体温过低 批准在出生后6小时内用于缺氧缺血，尚未批准用于围产期 动脉缺血性卒中，因为临床试验分层需要明确诊断， 出生估计发病率为每100，000例活产17 - 93例，围产期中风发病率 与成人中风发病率（17 - 23/100，000）相当。因此，一种可以快速可靠地 在出生后不久确定一个局灶性脑缺血区域将产生重大影响， 在早期的治疗时间窗口，神经保护剂将最大限度地提高疗效。Brimrose技术 公司与约翰霍普金斯大学合作，提出了一种光声头盔（PAH）设备， 安全地部署在新生儿重症监护病房的床边，以1）连续监测和快速监测 在新生儿出生后不久就识别出高危新生儿，迅速将其分类治疗; 2）监测进展情况 3）为有终身脑损伤风险的新生儿父母提供预后信息。的 PA成像机制是一种纯混合机制，提供了组织氧合物的丰富的光吸收对比度。 和脱氧血红蛋白的混合物检测组织减少的概念验证 用标准实验室PA激光已经证明了在1cm诱导的实验性中风中的氧合血红蛋白 光源和临床超声探测器。我们的目标是采用更安全的发光二极管（LED）， 在新生儿头盔中配置更灵敏的超声检测器，以定位低密度皮质区域， 新生儿的氧合。在拟议的第一阶段STTR中，我们将开发基本硬件和软件 有效整合的组成部分。目标1-用于高对比度分辨率下安全PAH成像的软件，包括 深度神经网络和最佳光谱分解技术，以实现安全和高速的LED PAH 系统目标2-模块化PAH系统的硬件，包括光纤耦合Brimrose超灵敏多功能 用于高时空谱下PAH成像的反射激光麦克风和最佳模块化单元设计 通过完整的头皮和头骨的分辨率。目标3-模块化PAH系统集成框架， PAH系统中的模块化单元与使用光学跟踪的刚体标签配准的鲁棒集成， 其可以适应不同的新生儿头部形状和对不同成像规格的需要。的 第一阶段的里程碑是在<10 mm的半高全宽处检测到全血氧饱和度范围， 横向平面和5 mm传感深度通过离体新生仔猪颅骨+头皮样品， 一套硬件和软件包，允许在第二阶段进行临床前验证研究。

PROJECT SUMMARY/ABSTRACT Neonatal encephalopathy can arise from fetal hypoxia-ischemia during labor, chronic uteroplacental inflammation, and large cerebral artery embolization primarily arising from dislodgement of a placental thrombus. Because of overlapping clinical presentation, differential diagnosis is often delayed until seizures develop and MRI can be safely performed, a time at which most neuroprotectants are ineffective. Whereas hypothermia is approved for use within 6 hours of birth for hypoxia-ischemia, no treatments have been approved for perinatal arterial ischemic stroke because of the difficulty of definitive diagnosis required for clinical trial stratification at birth. With an estimated incidence of 17-93 per 100,000 live births, the incidence of stroke in the perinatal period rivals the incidence of stroke in adults (17-23 per 100,000). Therefore, a device that could rapidly and reliably identify an area of focal cerebral ischemia soon after birth would have a major impact by enabling the testing of neuroprotectants at an early therapeutic time window that would maximize efficacy. The Brimrose Technology Corporation, partnering with Johns Hopkins University, propose a photoacoustic helmet (PAH) device that can be safely deployed at the bedside in the neonatal intensive care unit to 1) continuously monitor and rapidly identify at-risk neonates, shortly after birth, rapidly allowing them to be triaged to therapy; 2) monitor the progress of therapy; and 3) provide prognostic information to the parents of newborns at risk for life-long brain injury. The PA imaging mechanism is a purely hybrid mechanism, providing rich optical absorbance contrast of tissue oxy- and deoxyhemoglobin through intact scalp and skull. A proof-of-concept of detecting decreased tissue oxyhemoglobin in a 1 cm-induced experimental stroke has been demonstrated with standard laboratory PA laser light source and clinical ultrasound detector. Our goal is to incorporate safer light-emitting diodes (LEDs) and more sensitive ultrasound detectors configured in a neonatal helmet to localize cortical regions of low oxygenation in the newborn. In the proposed Phase-I STTR, we will develop fundamental hardware and software components for effective integration. Aim 1 - Software for safe PAH imaging at high contrast resolution, including deep neural network and optimal spectral unmixing techniques to enable a safe and high-speed LED-based PAH system. Aim 2 - Hardware for modular PAH system, including a fiber-coupled Brimrose ultra-sensitive multi- bounce laser microphone and optimal modular unit design for a PAH imaging at high spatial-temporal-spectral resolution through intact scalp and skull. Aim 3 - Framework for modular PAH system integration, enabling a robust integration of modular units in a PAH system with rigid-body tag registration using optical tracking, in which different neonatal head shapes and need for different imaging specifications can be accommodated. The Phase-I milestone is detection of the full blood O2 saturation range at <10 mm full-width-half-maximum in the transverse plane and 5 mm sensing depth through ex vivo neonatal piglet skull + scalp sample with an integrated set of hardware and software packages, allowing preclinical validation studies to proceed in Phase II.