Optical Fiber Sensing System Monitors Post TBI Complications

After a traumatic brain injury, such as a concussion, secondary damage from brain swelling can occur. While biomarkers in blood or spinal fluid provide valuable insights into brain health, many current methods face challenges in simultaneously monitoring multiple biomarkers. Researchers have now developed an optical fiber sensing system that could enable medical professionals to track complications following a traumatic brain injury. This technology allows for the continuous, automatic monitoring of six biomarkers simultaneously, offering critical information on brain health during lab tests.

Fiber optics, known for their ability to transmit information at extremely high speeds, have applications beyond just internet connections. Researchers from Imperial College London (London, UK) set out to design an optical fiber system capable of simultaneously monitoring six vital biomarkers of brain health: temperature, pH, and concentrations of dissolved oxygen, glucose, sodium ions, and calcium ions. Optical fibers, similar to those used in underground cabling, are ideal for medical purposes due to their small size and ability to interact with light-absorbing biomarkers or tissues in detectable patterns. The researchers equipped six optical fibers with fluorescent tips specific to each biomarker. A multi-wavelength laser was directed through the fibers to monitor the analytes. When a target analyte interacted with a fluorescent tip, the resulting change in brightness was captured by a computer.

The researchers integrated these six fibers, along with an additional fiber to enhance the calcium signal, into a 2.5-millimeter-thick catheter to create a cerebrospinal fluid sensing system. Machine-learning algorithms were employed to separate the fluorescence signals, making it easy to interpret each biomarker's readout. In animal experiments simulating the conditions of a human brain after a traumatic injury, the catheter successfully detected the six biomarkers. The system was then tested on cerebrospinal fluid samples from healthy human participants, which were spiked with the relevant brain health biomarkers. The sensing system accurately measured pH, temperature, and dissolved oxygen levels and identified changes in ion and glucose concentrations. According to the researchers, this work, published in ACS Sensors, demonstrates that their optical fiber system can identify potential secondary injuries and help monitor complications in patients recovering from traumatic brain injuries.