A MEMS intracranial pressure device for monitoring brain injuries and disorders

用于监测脑损伤和疾病的 MEMS 颅内压装置

• 批准号: 7920138
• 负责人: Nikolaos Chronis
• 金额: $ 20.8万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7920138
• 关键词: Address; Architecture; Bathing; Blood; Brain; Brain Injuries; Catheters; Cerebrospinal Fluid; Cerebrospinal Fluid Pressure; Cessation of life; Clinical Trials; Code; Collection; Color; Development; Devices; Diagnostic; Disease; Electronics; Fluorescence; Future; Goals; Hydrocephalus; Imaging technology; Implant; In Vitro; Infection; Injury; Intracranial Hypertension; Intracranial Pressure; Length; Lesion; Light; Liquid substance; Magnetic Resonance Imaging; Microfabrication; Monitor; Operative Surgical Procedures; Optics; Patient Monitoring; Patients; Pentobarbital; Performance; Pharmaceutical Preparations; Physiology; Probability; Process; Quantum Dots; Reaction Time; Recovery; Research; Resolution; Risk; Signal Transduction; Silicon; Skin Absorption; Structure; Surface; System; TBI Patients; Technology; Temperature; Testing; Thick; Time; Tissues; Traumatic Brain Injury; Work; base; design; gastrointestinal pressure; implantation; in vivo; miniaturize; monitoring device; mortality; novel; operation; pressure; prototype; public health relevance; ratiometric; sensor; tool

DESCRIPTION (provided by applicant): Intracranial pressure (ICP) monitoring is an essential diagnostic tool for the efficient treatment of patients with brain injuries (e.g. traumatic brain injuries (TBIs)) and cerebrospinal fluid outflow disorders (e.g. hydrocephalus). Clinical trials have shown that ICP monitoring decreases the mortality rate and minimizes secondary injuries. Various ICP monitoring systems have been successful so far in accurately monitoring ICP, but: (a) they have high probability of infection (up to 15%), (b) they do not allow long-term ICP monitoring and (c) they are not MRI (Magnetic Resonance Imaging) compatible. Taking advantage of recent developments in the MicroElectroMechanical Systems (MEMS) field, we propose an 'Intracranial Pressure Micro Stick' (IP<S) technology that overcomes the aforementioned limitations. The technology is based on a fully implantable (cable-free), optical, MEMS device that 'color' codes ICP changes: ICP is converted to a ratiometric optical signal in the near infrared (NIR) wavelength. The device consists of a tunable microlens that focuses light into a quantum-dot bilayer. Each of the two layers contains NIR quantum dots of a unique wavelength. The focal length of the microlens is altered when the ICP changes, resulting in a change in the ratiometric intensity of the two wavelengths. A non-implantable, portable optical unit is used to excite the microlens/quantum dot assembly and collect the emitted NIR spectrum. The electronic- free (and thus power-free) IP<S device enables prolonged ICP monitoring, eliminates the risk of infection, allows patient's comfort and mobility and it is MRI compatible. We propose a research plan with the following specific aims: (a) Optimization of the tunable microlens/quantum dot bilayer assembly: the tunable microlens/quantum dot bilayer assembly will be optimized with respect to the microlens collection efficiency, internal microlens pressure resolution, dynamic range, and quantum dot bilayer thickness; (b) Microfabrication and testing of the integrated IP<S device: an IP<S prototype will be microfabricated and its specifications will be established (ICP range, resolution, time response); (c) In-vitro Studies: We will perform in vitro studies by immersing the integrated device in a bath containing cerebrospinal fluid (CSF). The pressure of the CSF will be externally adjusted to represent a real ICP monitoring scenario and the long term durability and zero drift of the device will be determined. The proposed technology will help in efficiently managing and treating brain injuries and CSF outflow disorders, and it will inaugurate the development of implantable and power-free, miniaturized devices that can be used in a variety of pressure monitoring biomedical applications. PUBLIC HEALTH RELEVANCE: Intracranial pressure (ICP) monitoring is an important diagnostic tool for accessing the pathological condition of patients with traumatic brain injury (TBI), congenital or acquired hydrocephalus or mass lesions. This work aims to develop a new class of implantable ICP monitoring devices that will provide better management and efficient treatment of patients with elevated ICP.

描述(申请人提供)：颅内压监测是有效治疗脑损伤(如创伤性脑损伤)和脑脊液流出障碍(如脑积水)患者的基本诊断工具。临床试验表明，颅内压监测降低了死亡率，并最大限度地减少了二次损伤。到目前为止，各种颅内压监测系统在准确监测颅内压方面取得了成功，但：(A)它们感染的可能性很高(高达15%)，(B)它们不能进行长期的颅内压监测，以及(C)它们与磁共振成像(MRI)不兼容。利用微电子机械系统(MEMS)领域的最新发展，我们提出了一种“颅内压力微棒”(IP&lt；S)技术，它克服了上述限制。这项技术是基于一种完全可植入(无电缆)的光学MEMS设备，该设备可以用颜色编码ICP的变化：将ICP转换为近红外(NIR)波长下的比率光学信号。该装置由一个可调谐的微透镜组成，它将光聚焦到量子点双层中。这两层中的每一层都包含唯一波长的近红外量子点。微透镜的焦距会随着ICP的变化而改变，从而导致两个波长的比值强度发生变化。使用不可植入的便携式光学单元来激励微透镜/量子点组件并收集发射的近红外光谱。无电子(因此无电源)的IP&lt；S设备能够实现长时间的颅内压监测，消除感染风险，使患者舒适和移动，并且它与磁共振兼容。我们提出了一项具有以下具体目标的研究计划：(A)可调谐微透镜/量子点双层组件的优化：可调谐微透镜/量子点双层组件将从微透镜的收集效率、内部微透镜的压力分辨率、动态范围和量子点双层膜厚度方面进行优化；(B)集成IP&lt；S器件的微加工和测试：将对IP&lt；S原型进行微加工，并建立其性能指标(ICP值范围、分辨率、时间响应)；(C)体外研究：我们将通过将集成设备浸入含有脑脊液的浴缸中进行体外研究。脑脊液的压力将从外部进行调整，以代表真实的颅内压监测场景，并将确定设备的长期耐用性和零漂移。这项拟议的技术将有助于有效地管理和治疗脑损伤和脑脊液流出障碍，并将开启可植入且无动力的微型设备的开发，这些设备可用于各种压力监测生物医学应用。 公共卫生相关性：颅内压监测是评估创伤性脑损伤(TBI)、先天性或获得性脑积水或肿块病变患者病理状况的重要诊断工具。这项工作旨在开发一种新型植入式颅内压监测装置，为颅内压升高的患者提供更好的管理和有效的治疗。