Wireless, Self-Powered Sensors for Continuous and Long-term Monitoring of Spinal Fusion Process

用于连续长期监测脊柱融合过程的无线自供电传感器

• 批准号: 10001440
• 负责人: Amir Alavi
• 金额: $ 17.27万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2021-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10001440
• 关键词: Acute; Animals; Benchmarking; Biomechanics; Cadaver; Chemicals; Cost Measures; Data; Data Storage and Retrieval; Detection; Devices; Diagnostic Procedure; Diagnostic radiologic examination; Ensure; Evolution; Excision; Exposure to; Face; Future; Goals; Harvest; Human; Image; Imaging Techniques; Imaging technology; Implant; In Vitro; Life; Measures; Mechanics; Medical; Methods; Modality; Modeling; Monitor; Morphologic artifacts; Motion; Nature; Operative Surgical Procedures; Outcome; Outcome Study; Output; Patients; Performance; Postoperative Complications; Procedures; Process; Radiation; Recording of previous events; Rehabilitation therapy; Research; Research Activity; Rest; Risk; Rod; Schedule; Silicon; Solid; Spinal; Spinal Fusion; System; Techniques; Technology; Telemetry; Testing; Time; Tissues; Transducers; Ultrasonics; Ultrasonography; United States; Variant; Vertebral column; Weight-Bearing state; Wireless Technology; Work; X-Ray Computed Tomography; base; bone; bone healing; clinically relevant; cost; design; empowered; experience; experimental study; healing; implantable device; instrumentation; mechanical load; millimeter; miniaturize; next generation; operation; portability; prototype; radio frequency; research study; sample fixation; sensor; stem; success; surgery outcome; temporal measurement; tool; wireless communication

PROJECT SUMMARY Achieving better surgical outcomes and research studies involving lumbar spinal fusion requires reliable determination and degree of fusion. Current imaging technologies are not suitable to accurately and reliably determine different degrees of spinal fusion. These modalities are costly and expose the patient to significant radiation. In addition, nearly all of the previously developed implantable telemetry systems comprise on-board energy storage devices (batteries and super-capacitors) for sensing, computation, storage, and wireless communication. The use of batteries in biomedical implants is not suitable due to their limited life time, large size, and chemical risks. The rest of these spinal implants use radio-frequency identification (RFID) technology or other inductive methods to interrogate the sensor, which faces severe limitations inside the tissue. Similar to the imaging techniques, the current spinal implants evaluate the fusion condition at a given instant and present only a “snapshot at the time” where the measurements are taken. In this research study, we propose to investigate the feasibility of a wireless, self-powered piezo-floating-gate (PFG) sensor capable of monitoring the spinal fusion progress by continuously recording the mechanical usage of the spinal fixation device during the entire time course of fusion. The uniqueness of the proposed sensor is that the operation is completely self-powered by the micro-motion of the spine without the need for any implanted batteries or any external powering. Data collected by the sensor will be wirelessly retrieved using a portable ultrasound-scanner and the resulting output will be time-evolution curves, which will be correlated with the changes of functional spinal unit (FSU) stiffness. These evolution curves would enable clinicians to differentiate between conditions of osseous union, assess the effective fusion period, and schedule for more accurate implant removal in several types of spinal fusion procedures. Our first objective for this research will be to design a fully integrated spinal fusion implant with self-powered monitoring and wireless data retrieval capabilities. The research activity will involve designing and prototyping the ultrasonic energy harvesting and telemetry circuits in silicon and subsequently validating the functionality of the fabricated modules using a cadaver model. The challenge will be to achieve high energy efficiency of the telemetry circuit modules given the limited amount of energy that can be delivered by the ultrasound scanner to a millimeter-scale sensor. Our second objective will be bench-top testing to evaluate the performance of the PFG sensor and the ultrasonic telemetry interface for the monitoring of simulated posterior lumbar spinal fusion in human cadaver spines. Prior to testing on cadaver spines, the PFG spinal implants will be tested using a corpectomy model. Upon successful completion of this study, we will have demonstrated acute in-vitro monitoring of clinically relevant dynamics underlying the process of spinal fusion. Such a powerful tool would enable design of the next-generation, smart fixation-devices with self-monitoring capabilities.

项目摘要 实现更好的手术结果和研究研究涉及腰椎融合需要可靠的 融合度和融合度。当前的成像技术不适合于准确和可靠地进行成像。 决定不同程度的脊柱融合。这些模式是昂贵的，并且使患者暴露于显著的风险。 辐射此外，几乎所有先前开发的植入式遥测系统都包括机载遥测系统。 用于传感、计算、存储和无线通信的能量存储设备（电池和超级电容器） 通信在生物医学植入物中使用电池是不合适的，因为它们的寿命有限， 尺寸和化学风险。其余这些脊柱植入物使用射频识别（RFID）技术 或其它感应方法来询问传感器，这在组织内面临严重的限制。类似于 成像技术、当前的脊柱植入物评估给定时刻和当前的融合状况 只有进行测量的“当时的快照”。 在这项研究中，我们建议调查的可行性，无线，自供电的压电浮栅 (PFG)能够通过连续记录机械使用来监测脊柱融合进展的传感器 脊柱固定装置在整个融合过程中的作用。所提出的传感器的独特性是 手术完全是由脊柱的微运动提供动力， 电池或任何外部电源。传感器收集的数据将使用便携式无线检索 超声扫描仪和所得到的输出将是时间演变曲线，这将与 功能性脊柱单位（FSU）刚度的变化。这些演变曲线将使临床医生能够区分 在骨愈合条件之间，评估有效融合期，并安排更准确的植入物 在几种类型的脊柱融合手术中移除。 我们这项研究的第一个目标是设计一个完全集成的脊柱融合植入物， 监控和无线数据检索能力。研究活动将涉及设计和原型制作 超声波能量收集和遥测电路在硅和随后验证的功能 使用尸体模型制造模块。所面临的挑战将是实现高能源效率的 遥测电路模块给出了可以由超声扫描器递送的有限量的能量， 毫米级传感器我们的第二个目标将是台式测试，以评估PFG的性能 传感器和超声遥测接口，用于监测模拟腰椎后路融合术， 人类尸体的脊柱在对尸体脊柱进行测试之前，将使用 椎体切除模型成功完成本研究后，我们将证明急性体外 监测脊柱融合过程中的临床相关动力学。如此强大的工具 能够设计出具有自我监控功能的下一代智能固定设备。