Conformable Skin-Mounted Device for Subdermal Fluid Flow Measurement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing diagnostics for ventricular shunt malfunction in hydrocephalus are invasive, costly, and inaccurate, leading to unnecessary procedures and high failure rates, with a need for a noninvasive, wireless, and conformable monitoring solution.
Innovation Solution
A soft, wireless, noninvasive, skin-mounted device using thermal transport to measure cerebrospinal fluid flow in shunts, composed of silicone rubber, with upstream and downstream temperature sensors, and a microprocessor for continuous monitoring, transmitting data via Bluetooth.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If invasive diagnostic methods are used to detect shunt malfunction, then measurement accuracy is improved, but patient harm and procedural complexity increase
Solution Approach 1:
The patent replaces invasive mechanical diagnostic procedures with a noninvasive thermal sensing system. Temperature sensors detect thermal changes in the skin caused by cerebrospinal fluid flow through the shunt, eliminating the need for invasive procedures while maintaining diagnostic accuracy.
Solution Approach 2:
The patent uses thermal energy as an intermediary to detect shunt function. Instead of directly measuring fluid flow or pressure invasively, the system measures thermal changes in the skin that are caused by the flow of cerebrospinal fluid through the shunt, providing indirect but accurate measurement.
2Reliability
If continuous monitoring is implemented to capture occult malfunction, then diagnostic reliability is improved, but device complexity and power requirements increase
Solution Approach 1:
The patent implements periodic thermal sensing measurements rather than continuous monitoring. The system periodically activates the thermal sensor to measure temperature changes, which reduces power consumption and device complexity while still capturing occult malfunctions that occur intermittently.
Solution Approach 2:
The patent uses the body's own thermal energy and natural heat transfer processes to perform the monitoring function. The system leverages the temperature differential created by cerebrospinal fluid flow itself, eliminating the need for complex active heating or cooling mechanisms.
3Ease of operation
If wireless operation is achieved without hard-wire connections, then patient comfort and ease of operation are improved, but power supply and data transmission reliability may worsen
Solution Approach 1:
The patent uses a flexible, thin-film substrate to mount the thermal sensors and electronic components. This allows the device to be conformally attached to the skin in a wireless configuration, maintaining patient comfort and mobility while enabling reliable thermal measurements through direct skin contact.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Provides accurate, continuous, and painless monitoring of shunt function, capturing occult malfunctions, and facilitating long-term patient comfort with reduced clinical impact.
Implementation Method 1
The epidermal device exploits the precise measurement of thermal transport to characterize CSF flow in underlaid shunts
Implementation Method 2
upstream temperature sensor and downstream temperature sensor to measure temperature differential induced by fluid flow
Data Source
Figure 1A~1B
Figure 1C~1D
Figure 1E~2B
AI summary
Provided are conformable devices to measure subdermal fluid flow and related methods. A soft, stretchable and flexible substrate supports a thermal actuator and various specially positioned temperature sensors. A microprocessor in electronic communication with sensors calculates subdermal fluid flow from the measured upstream and downstream temperatures, as well as various application-dependent parameters. Devices and methods provided herein are particularly useful for measuring cerebral spinal fluid in a ventricular shunt placed for treatment of hydrocephalus.