Continuous, noninvasive wireless monitoring of flow of cerebrospinal fluid through shunts in patients with hydrocephalus

Abstract

Hydrocephalus is a common disorder caused by the buildup of cerebrospinal fluid (CSF) in the brain. Treatment typically involves the surgical implantation of a pressure-regulated silicone tube assembly, known as a shunt. Unfortunately, shunts have extremely high failure rates and diagnosing shunt malfunction is challenging due to a combination of vague symptoms and a lack of a convenient means to monitor flow. Here, we introduce a wireless, wearable device that enables precise measurements of CSF flow, continuously or intermittently, in hospitals, laboratories or even in home settings. The technology exploits measurements of thermal transport through near-surface layers of skin to assess flow, with a soft, flexible, and skin-conformal device that can be constructed using commercially available components. Systematic benchtop studies and numerical simulations highlight all of the key considerations. Measurements on 7 patients establish high levels of functionality, with data that reveal time dependent changes in flow associated with positional and inertial effects on the body. Taken together, the results suggest a significant advance in monitoring capabilities for patients with shunted hydrocephalus, with potential for practical use across a range of settings and circumstances, and additional utility for research purposes in studies of CSF hydrodynamics.

Cohabiting Plant‐Wearable Sensor In Situ Monitors Water Transport in Plant

“…[38] Such methods are complicated and time-consuming or destructive; thus, continuous monitoring of the sap flow for a relatively long period for plants is not possible. [29,39] The recently reported flexible/wearable electronic flow sensors, based on analyzing the time/spatial thermal responses of tissues to the fluids, shed light on how to non-destructively measure flows in complex biointerfaces, such as blood flow, [40][41][42] cerebrospinal fluid, [43] sweat and interstitial fluid, [44] and airflow. [45][46][47] However, a plant-wearable sensor that can continuously monitor its sap flow and harmlessly cohabitate with a plant is still challenging.…”

Multimodal Sensing Capabilities for the Detection of Shunt Failure

“…We tested three different flow rates: 0.01, 0.1, and 0.3 mL/min. Here, a flow rate of 0.3 mL/min indicated a shunt was operating normally, 0.01 mL/min represented a shunt failure associated with obstructions in a catheter [ 23 , 24 , 32 ], and 0.1 mL/min was chosen as a mid-point to evaluate the changes in pressure and resistance. We monitored pressure and resistance over 30 min at various flow rates under two different conditions: dry and wet conditions.…”

“…A recent study proposed to determine whether a shunt is malfunctioning through a non-invasive device that can estimate the catheter flow rate as a function of temperature change. The existing non-invasive approach uses localized thermal actuation, but CSF flow rate calculation is heavily dependent on variable parameters, such as skin thickness and thermal properties that vary in individuals [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 ]. This indicates that a threshold for detection of shunt failure can vary in individuals, and that a setting for measurements of CSF flow rate must be customized to an individual.…”

United States Medicolegal Progress and Innovation in Telemedicine in the Age of COVID-19: A Primer for Neurosurgeons

“… 59 Next-generation devices in epilepsy and hydrocephalus that can be accessed and programmed remotely lend themselves to telemedicine. 59 , 60 Such devices can potentially monitor patients in real time with strategies to alert the provider and patients before a problem becomes clinically apparent.…”