Bioimpedance-based Intracranial Mapping for Monitoring Evolving TBI

摘要 每年约有300万人遭受创伤性脑损伤，预计将超过5万人 因受伤而死亡。在这些最严重的病例中，患者通常被送往重症监护室。 重症监护室(ICU)，持续监测和治疗他们的伤害。标准监测包括植入 颅内压传感器、动脉血压监测和偶尔成像 研究(通常是CT检查)。这些监测策略的目标是检测正在演变的病理 及时为这些患者提供治疗，以防他们的伤害升级到 哪种治疗方法变得无效。不幸的是，这些策略在检测能力方面是有限的 不断恶化的条件。ICP值的飙升代表了恶化状况的全球衡量标准，但它并没有提供 本地化信息，通常达到关注水平(&gt；20毫米汞柱)比临床上希望的要晚得多。 ABP传感与ICP结合代表了脑灌流压力的替代测量，但很难 准确测量。偶尔的影像检查可以提供精致的颅内细节，但很难管理。 在重症监护病房的患者中，只有偶尔才会获得，通常在受伤开始后 进步。我们建议通过开发一种小型表格来克服当前监测策略的局限性- 因素，实时连续监测，能够对演变中的颅内创伤进行空间映射。具体来说，我们 为此，建议使用一种经过修改的阻抗频谱分析方法。我们的新方法 利用头皮和颅内电极绘制相关的动态颅内阻抗变化图 创伤引起的体液和组织改变。我们已经在一项动物实验中证明了这一点 一种类型的模式能够检测到由于肿块效应、血肿和脑死亡引起的颅内变化。 在这项计划中，我们将迈出重要的一步，将这项技术用于商业部署 并在动物模型中使用术中CT扫描来证明其可行性。因为这件事 正在设计系统，以最小限度地增强现有的临床方案(设计为与 ICU中的重型仪器患者)，相对便宜(10000英镑的电阻抗采集 系统)，并且潜在地能够在当前临床接受之前检测到演变中的颅内损伤 技术，这项技术有可能很容易被翻译成临床并被临床接受 持续监测颅脑损伤后患者的益处。我们预计到这个节目结束时，我们将 能够提交第二阶段申请，重点是优化我们的技术并进行 更大样本量的动物模型试验，以证明我们的颅内阻抗映射技术的有效性。

ABSTRACT Approximately 3 million individuals suffer from traumatic brain injury (TBI) annually, with over 50,000 expected to die as a result of their injury. In these most severe cases, patients are typically admitted to the intensive care unit (ICU) for continuous monitoring and treatment of their injury. Standard monitoring includes implantation of an intracranial pressure (ICP) sensor, arterial blood pressure (ABP) monitoring, and occasional imaging studies (typically with CT). The objective of these monitoring strategies is to detect evolving pathology in a timely manner so that treatment can be provided to these patients prior to their injury escalating to a point at which treatment becomes ineffective. Unfortunately, these strategies are limited in their ability to detect worsening conditions. Spiking ICP represents a global measure of worsening status, however it provides no localizing information and typically reaches levels of concern (>20 mmHg) much later than is clinically desired. ABP sensing coupled with ICP represents a surrogate measure of cerebral perfusion pressure, but is difficult to accurately gauge. Occasional image studies provide exquisite intracranial details, but are difficult to administer in heavily instrumented ICU patients and are only acquired occasionally, often after injury has begun to progress. We propose to overcome the limitations of current monitoring strategies by developing a small form- factor, real-time continuous monitor, able to spatially map evolving intracranial trauma. Specifically, we propose to use an adapted form of electrical impedance spectroscopy for this purpose. Our novel approach leverages both scalp and intracranial electrodes to map dynamic intracranial impedance changes associated with fluid and tissue alterations resulting from trauma. We have demonstrated in a pilot animal study that this type of modality is capable of detecting intracranial changes due to mass effect, hematoma, and brain death. During this program we will take the significant step of developing this technology for commercial deployment and demonstrating proof of feasibility in an animal model using intraoperative CT scanning. Because this system is being designed to minimally augment an already existing clinical protocol (designed to interface with a heavily instrument patient in the ICU), is relatively inexpensive (<$10k for an electrical impedance acquisition system), and is potentially able to detect evolving intracranial injury prior to current clinically-accepted technologies, this technology has the potential of being easily translated to and accepted by the clinic for the benefit of continuously monitoring patients following TBI. We expect that by the end of this program we will be in a position to submit a Phase II application that will focus on optimizing our technology and conducting a larger sample size animal model trial to demonstrate efficacy of our intracranial impedance mapping technique.