Wireless Pressure Sensor Research Articles

Single center experience of internal jugular vein as alternative access for implantation of a wireless pulmonary artery pressure sensor

Abstract This single-center study delves into the novel use of the internal jugular vein (IJ) as an alternative access pathway for the implantation of the CardioMEMS device, a wireless pulmonary artery pressure sensor. This approach is compared to the conventional femoral vein access in terms of procedural times, contrast volume, and patient outcomes. The study spans five years, from 2018 to 2023, evaluating the efficacy and safety of IJ access for CardioMEMS implantation. The analysis revealed a tendency towards shorter procedural times and reduced contrast volume with IJ access, although statistical significance was not reached due to the small sample size. Notably, IJ access provided a quicker needle-to-door time, suggesting benefits such as improved patient throughput and potentially shorter hospital stays, which are pivotal in a healthcare landscape that prioritizes efficiency and cost-effectiveness. In conclusion, this investigation offers initial evidence that IJ vein access is a feasible and potentially superior alternative for CardioMEMS device implantation. While the findings are preliminary due to the study's limited scale, they pave the way for future larger-scale, multicenter studies. Such research could confirm the benefits of IJ access and possibly influence clinical practices, enhancing the management of heart failure patients.

A wireless multiparameter cryogenic monitoring method using passive backscatter sensors

In this paper, we proposed the first wireless multiparameter monitoring method for cryogenic environments (−196 ℃). Present-day cryogenic industries implement a large array of wired sensors to monitor key parameters in fabrication processes. The wirings for a large sensor array greatly complicate the monitoring system. We presented the first wireless multiparameter monitoring method for cryogenic environments by making two efforts. First, a novel wireless passive vibration and pressure sensor is developed. We transfer vibrations and pressures to a relative displacement between a magnet and a tunnel magnetoresistor (TMR). This affects the magnetic field at the TMR and changes the TMR’s resistance. By integrating the TMR on a backscattering antenna, the antenna’s wireless return loss is modulated by both vibrations and pressures. We proposed a decoupling method for simultaneously monitoring vibration and pressure by a single sensor. Second, we demonstrated and evaluated the first wireless multiparameter cryogenic monitoring system. A wireless passive temperature sensor is developed by integrating a resistance temperature detector (RTD) on a backscattering antenna. The developed vibration and pressure sensor and temperature sensor are tuned to separate frequency bands, embedded in cryogenic environments, and calibrated in situ. Vibrations, pressures, and temperatures in cryogenic environments are synchronously obtained by our wireless cryogenic monitoring system, with an accuracy of 80∼90 %. This research provides a wireless option in large-scale automated cryogenic monitoring, thus it is desirable in implementing the Internet of Things in cryogenic industries.

The PolyCraft Polymer–Metal Hybrid Smart Stent System: The Future of Cardiovascular Blood Pressure Management

AbstractTo address the complication of in‐stent restenosis that occurs with traditional stent treatments, this study proposes an innovative hybrid smart stent‐based medical system. This approach allows to overcome the limitations of existing bare metal or polymer‐based smart stents, which interfere with radio frequency signals, less deformability, or do not provide adequate radial support, respectively. The proposed hybrid stent, which uses a Co/Cr–polycaprolactone (PCL)–Co/Cr configuration connected by a unique dual inverted Y‐type connector for metal–polymer integration is integrated with a LC wireless pressure sensor fabricated through a semiconductor process. The fabricated hybrid stent made by laser machining and custom‐made 3D printing, offers excellent properties such as radial strength (0.125 N/mm) and flexibility (2 N mm2) and provides intravascular information to the outside through the integrated sensor without signal degradation. After basic experiments using a phantom, animal experiments are conducted by combining the fabricated sensor with artificial blood vessel, and the results measured by the external antenna system are consistent with the results of a commercial reference sensor. The proposed wireless sensor‐based smart stents and artificial blood vessels aim to gather diverse patient health data for integration with artificial intelligence, laying the groundwork for next‐generation medical innovation.

Wireless and Catheter-Free Bladder Pressure and Volume Sensor.

Continuous monitoring of bladder activity during normal daily activities would improve clinical diagnostics and understanding of the mechanisms underlying bladder function, or help validate how differing neuromodulation strategies affect the bladder. This work describes a urological monitor of conscious activity (UroMOCA). The UroMOCA included a pressure sensor, urine impedance-sensing electrodes, and wireless battery recharge and data transmission circuitry. Components were assembled on a circuit board and encapsulated with an epoxy/silicone molded package that allowed Pt-Ir electrode feedthrough for urine contact. Packaged UroMOCAs measured 12 × 18 × 6 mm. UroMOCAs continuously transmitted data from all onboard sensors at 10 Hz at 30 cm range, and ran for up to 44 hours between wireless recharges. After in vitro calibration, implantations were performed in 11 animals. Animals carried the device for 28 days, enabling many observations of bladder behavior during natural, conscious behavior. In vivo testing confirmed the UroMOCA did not impact bladder function after a two-week healing period. Pressure data in vivo were highly correlated to a reference catheter used during an anesthetized follow-up. Static volume sensor data were less accurate, but demonstrated reliable detection of bladder volume decreases, and distinguished between voiding and non-voiding bladder events.

Wireless Bioelectronics for In Vivo Pressure Monitoring with Mechanically-Compliant Hydrogel Biointerfaces.

Recent electronics-tissues biointefacing technology has offered unprecedented opportunities for long-term disease diagnosis and treatment. It remains a grand challenge to robustly anchor the pressure sensing bioelectronics onto specific organs, since the periodically-varying stress generated by normal biological processes may pose high risk of interfacial failures. Here, a general yet reliable approach is reported to achieve the robust hydrogel interface between wireless pressure sensor and biological tissues/organs, featuring highly desirable mechanical compliance and swelling resistance, despite the direct contact with biofluids and dynamic conditions. The sensor is operated wirelessly through inductive coupling, characterizing minimal hysteresis, fast response times, excellent stability, and robustness, thus allowing for easy handling and eliminating the necessity for surgical extraction after a functional period. The operation of the wireless sensor has been demonstrated with a custom-made pressure sensing model and in vivo intracranial pressure monitoring in rats. This technology may be advantageous in real-time post-operative monitoring of various biological inner pressures after the reconstructive surgery, thus guaranteeing the timely treatment of lethaldiseases.

A Flexible Wireless Pressure Sensor Based on UHF RFID Technology

A Flexible Wireless Pressure Sensor Based on UHF RFID Technology

Soft, Long-Lived, Bioresorbable Electronic Surgical Mesh with Wireless Pressure Monitor and On-Demand Drug Delivery.

Current research in the area of surgical mesh implants is somewhat limited to traditional designs and synthesis of various mesh materials, whereas meshes with multiple functions may be an effective approach to address long-standing challenges including postoperative complications. Herein, a bioresorbable electronic surgical mesh is presented that offers high mechanical strength over extended timeframes, wireless post-operative pressure monitoring, and on-demand drug delivery for the restoration of tissue structure and function. The study of materials and mesh layouts provides a wide range of tunability of mechanical and biochemical properties. Dissolvable dielectric composite with porous structure in a pyramidal shape enhances sensitivity of a wireless capacitive pressure sensor, and resistive microheaters integrated with inductive coils provide thermo-responsive drug delivery system for an antibacterial agent. In vivo evaluations demonstrate reliable, long-lived operation, and effective treatment for abdominal hernia defects, by clear evidence of suppressed complications such as adhesion formation and infections.

Immobilizing Polyiodides with Expanded Zn2+ Channels for High‐Rate Practical Zinc‐Iodine Battery

AbstractAqueous zinc‐iodine battery (AZIB) has the advantage of low cost and high specific capacity but suffer from the soluble polyiodides shuttling and sluggish redox kinetics. Herein, these two limitations are addressed by employing a cathode additive (zirconium hydrogen phosphate, denoted as EI‐ZrP) which provides dual functions: an agent for polyiodide confinement, and abundant channels for zinc ion transport. An enlarged crystalline interlayer (from typical 7.5 to 18.3 Å) of the EI‐ZrP significantly enhances the ionic conductivity and simultaneously immobilizes polyiodides, leading to an accelerated conversion process. AZIB with EI‐ZrP in the iodine cathode exhibits a high capacity retention over 10,000 cycles (with a 0.02‰ decay rate per cycle). Quasi‐solid‐state Zn‐I2 pouch cell has been constructed using hydrogel‐paper as separator and EI‐ZrP additive, which delivers a high areal capacity under repeated bending. As a proof‐of‐concept demonstration, the paper battery is integrated to power a wireless flexible pressure sensor system (WFPSS). This strategy may shed light on the rational design of conversion‐type cathode materials for both energy storage and flexible portable electronics.

Design and Research of SIW Wireless Passive High-Temperature and Pressure Sensor

Design and Research of SIW Wireless Passive High-Temperature and Pressure Sensor

Wireless Human Motion Monitoring by a Wearable 3D Spiral Liquid Metal Sensor with a Spinning Top‐Shaped Structure

AbstractFlexible wireless pressure sensors based on the LC resonance principle have emerged for critical applications in wearable devices. However, the challenge remains to promote the sensing performance while maintaining good wearability of the devices. Herein, a 3D spiral liquid metal sensor (3D‐SLMS) is reported with a spinning top‐shaped structure for wireless human motion detection. The device is composed of only liquid metals embedded in Ecoflex elastomer, thus being highly flexible. The study develops a unique method to fabricate 3D‐SLMS by integration of mask‐assisted spraying of liquid metals and virtual molding tuned by vacuum. Under an external load, the deformation of the spinning top‐shaped structure leads to changes in both inductance and capacitance, offering a detectable shift in the resonant frequency of the sensor. The 3D‐SLMS technology allows for a high sensitivity of −0.502 MHz N−1, a limit of detection as low as 0.71 mN, fast response time of 0.6 s, and stretchability up to 158% without device failure. As a proof‐of‐concept, the wireless pressure detection of various human motions such as arm bending, fisting, boxing, coughing, and flatfoot diagnosis is successfully implemented, thus promising translation of wearable electronics for sport monitoring and medical rehabilitation.

Photothermal Lithography for Realizing a Stretchable Multilayer Electronic Circuit Using a Laser.

Photolithography is a well-established fabrication method for realizing multilayer electronic circuits. However, it is challenging to adopt photolithography to fabricate intrinsically stretchable multilayer electronic circuits fully composed of an elastomeric matrix, due to the opacity of thick stretchable nanocomposite conductors. Here, we present photothermal lithography that can pattern elastomeric conductors and via holes using pulsed lasers. The photothermal-patterned stretchable nanocomposite conductor exhibits 3 times higher conductivity (5940 S cm-1) and 5 orders of magnitude lower resistance change (R/R0 = 40) under a 30% strained 5000th cyclic stretch, compared to those of a screen-printed conductor, based on the percolation network formed by spatial heating of the laser. In addition, a 50 μm sized stretchable via holes can be patterned on the passivation without material ablation and electrical degradation of the bottom conductor. By repeatedly patterning the conductor and via holes, highly conductive and durable multilayer circuits can be stacked with layer-by-layer material integration. Finally, a stretchable wireless pressure sensor and passive matrix LED array are demonstrated, thus showing the potential for a stretchable multilayer electronic circuit with durability, high density, and multifunctionality.

Continuous monitoring of cardiovascular function with a smart stent incorporating a flexible and stretchable wireless pressure sensor

The development of smart stents, capable of monitoring cardiovascular diseases and communicating vascular abnormalities to medical doctors, has garnered significant attention in the field of biomedical engineering. Various ex-situ fabrication strategies have been proposed to concurrently manufacture the smart stent and pressure sensor, thereby reducing the risk of sensor detachment caused by blood flow. However, the practical utility of these devices is still limited due to the rigidity of the wireless pressure sensor. In this study, we propose a flexible and stretchable smart self-reporting stent that incorporates a wireless pressure sensor. The fabrication process has been optimized to create a serpentine-shaped wireless pressure sensor that matches the shape and flexibility of the polymer stent struts. We thoroughly investigated the structural integrity, resonance frequency, stretchability, flexibility, and radial force of the manufactured smart self-reporting stent under different conditions. The wireless pressure sensor demonstrated a sensitivity of 0.15 MHz mmHg−1, as determined through experimental analysis. To demonstrate the feasibility of the proposed smart stent, we implanted it into the arteries of a three-dimensional phantom system. The obtained results, combined with the flexible and stretchable nature of the proposed smart self-reporting stent, highlight its potential for effective monitoring of the heart’s functional dynamics and detection of in-stent restenosis.

First in Human Subjects Testing of the UroMonitor: A Catheter-free Wireless Ambulatory Bladder Pressure Monitor.

Urodynamics is the standard method of diagnosing bladder dysfunction, but involves catheters and retrograde bladder filling. With these artificial conditions, urodynamics cannot always reproduce patient complaints. We have developed a wireless, catheter-free intravesical pressure sensor, the UroMonitor, which enables catheter-free telemetric ambulatory bladder monitoring. The purpose of this study was twofold: to evaluate accuracy of UroMonitor pressure data, and assess safety and feasibility of use in humans. Eleven adult female patients undergoing urodynamics for overactive bladder symptoms were enrolled. After baseline urodynamics, the UroMonitor was transurethrally inserted into the bladder and position was confirmed cystoscopically. A second urodynamics was then performed with the UroMonitor simultaneously transmitting bladder pressure. Following removal of urodynamics catheters, the UroMonitor transmitted bladder pressure during ambulation and voiding in private. Visual analogue pain scales (0-5) were used to assess patient discomfort. The UroMonitor did not significantly alter capacity, sensation, or flow during urodynamics. The UroMonitor was also easily inserted and removed in all subjects. The UroMonitor reproduced bladder pressure, capturing 98% (85/87) of voiding and nonvoiding urodynamic events. All subjects voided with only the UroMonitor in place with low post-void residual volume. Median ambulatory pain score with the UroMonitor was rated 0 (0-2). There were no post-procedural infections or changes to voiding behavior. The UroMonitor is the first device to enable catheter-free telemetric ambulatory bladder pressure monitoring in humans. The UroMonitor appears safe and well tolerated, does not impede lower urinary tract function, and can reliably identify bladder events compared to urodynamics.

A novel real-time wireless sensor integration for enhancing positive pressure system operation in single limb passive vented circuit

Non-invasive ventilation has become increasingly popular with recent technological advancements, and with the adaption of turbine-based respiratory support, NIV devices are becoming more accessible. Non-Invasive ventilation consists of a single limb or a dual limb circuit, with the dual limb being the most sophisticated. However, single limb vented circuit being the most widely adopted. The use of proximal to mask flow, pressure, and external physiological sensors are still not widely adapted to the single limb vented circuit, restricting the quality of ventilation support, primarily in-home care scenarios. We present a novel study that implements a real-time wireless pressure and flow sensor control system to a bi-level ventilator for a modular approach towards non-invasive ventilatory support. Tidal Volume, Inspiratory trigger delay, time to minimum pressure, and flow and pressure curves examined present a proximal to patient wireless system that can enhance the performance of a single limb passive vented circuit.

Hemodynamic-Guided Heart Failure Management in Patients With Either Prior HF Hospitalization or Elevated Natriuretic Peptides

BackgroundIn patients with symptomatic heart failure (HF) and previous heart failure hospitalization (HFH), hemodynamic-guided HF management using a wireless pulmonary artery pressure (PAP) sensor reduces HFH, but it is unclear whether these benefits extend to patients who have not been recently hospitalized but remain at risk because of elevated natriuretic peptides (NPs). ObjectivesThis study assessed the efficacy and safety of hemodynamic-guided HF management in patients with elevated NPs but no recent HFH. MethodsIn the GUIDE-HF (Hemodynamic-Guided Management of Heart Failure) trial, 1,000 patients with New York Heart Association (NYHA) functional class II to IV HF and either previous HFH or elevated NP levels were randomly assigned to hemodynamic-guided HF management or usual care. The authors evaluated the primary study composite of all-cause mortality and total HF events at 12 months according to treatment assignment and enrollment stratum (HFH vs elevated NPs) by using Cox proportional hazards models. ResultsOf 999 evaluable patients, 557 were enrolled on the basis of a previous HFH and 442 on the basis of elevated NPs alone. Those patients enrolled by NP criteria were older and more commonly White persons with lower body mass index, lower NYHA class, less diabetes, more atrial fibrillation, and lower baseline PAP. Event rates were lower among those patients in the NP group for both the full follow-up (40.9 per 100 patient-years vs 82.0 per 100 patient-years) and the pre–COVID-19 analysis (43.6 per 100 patient-years vs 88.0 per 100 patient-years). The effects of hemodynamic monitoring were consistent across enrollment strata for the primary endpoint over the full study duration (interaction P = 0.71) and the pre–COVID-19 analysis (interaction P = 0.58). ConclusionsConsistent effects of hemodynamic-guided HF management across enrollment strata in GUIDE-HF support consideration of hemodynamic monitoring in the expanded group of patients with chronic HF and elevated NPs without recent HFH. (Hemodynamic-Guided Management of Heart Failure [GUIDE-HF]; NCT03387813)

Wireless Mid-height Pore Water Pressure Sensor

Abstract The triaxial apparatus is one of the most widespread testing devices used by geotechnical laboratories for identifying parameters characterizing soil strength and stiffness behavior. In order to do so, the triaxial apparatus has the ability to measure a number of key parameters, among which the measurement of axial force, axial strain, and pore water pressure in the soil play a key role. By default, the measurement of the latter parameter is carried out at the bottom of the sample or, in its more advanced form, at the mid-height of the sample. The second approach, however, introduces the requirement to break the continuity of the membrane surrounding the soil specimen, which can lead to water penetration from the cell into the sample. Nevertheless, this inconvenience can be avoided by using a novel sensor that measures water pressure in the soil pores wirelessly. In addition, as the membrane does not need to be perforated, sample preparation time can be reduced. This article presents the integration of the novel sensor into a triaxial apparatus and its validation in the form of a series of tests performed on several soil types to demonstrate the effectiveness and performance of the wireless water pressure sensor.

Fall Risk Prediction Using Wireless Sensor Insoles With Machine Learning

Accidental fall is a significant health risk among the elderly. However, most of the fall detection systems give notification only after a fall occurs. Therefore, medical attention has shifted to fall preventive measures to reduce risks of fall and prevent any damage entirely. As most fall prediction data in previous literature are obtained from inertial sensors or static pressure sensors, in this study, wireless pressure sensors embedded insoles are used to train machine learning (ML) models to predict the risk of fall of an individual. The novelty of this paper is that dynamic walking data is obtained by wearing smart pressure insoles from 1101 subjects. We applied six different ML models, i.e., support vector machine (SVM), random forest (RF), logistic regression (LR), naive bayes (NB), decision tree (DT), and k-nearest neighbor (kNN). Results show that LR model with oversampling techniques achieved the highest area under curve (AUC) of 0.82, whereas the RF model with oversampling achieved the highest accuracy of 0.81 and specificity of 0.88. The results show that such models combined with pressure embedded wireless sensor insoles are capable for fall risk prediction.

Battery-Free, Wireless, Ionic Liquid Sensor Arrays to Monitor Pressure and Temperature of Patients in Bed and Wheelchair.

Repositioning is a common guideline for the prevention of pressure injuries of bedridden or wheelchair patients. However, frequent repositioning could deteriorate the quality of patient's life and induce secondary injuries. This paper introduces a method for continuous multi-site monitoring of pressure and temperature distribution from strategically deployed sensor arrays at skin interfaces via battery-free, wireless ionic liquid pressure sensors. The wirelessly delivered power enables stable operation of the ionic liquid pressure sensor, which shows enhanced sensitivity, negligible hysteresis, high linearity and cyclic stability over relevant pressure range. The experimental investigations of the wireless devices, verified by numerical simulation of the key responses, support capabilities for real-time, continuous, long-term monitoring of the pressure and temperature distribution from multiple sensor arrays. Clinical trials on two hemiplegic patients confined on bed or wheelchair integrated with the system demonstrate the feasibility of sensor arrays for a decrease in pressure and temperature distribution under minimal repositioning.

A Wireless Transient Attenuated-Exponential Overpressure Beamforming With for Far-Field Blast Source Localization

Time-domain beamforming is more suitable for blast wave transient signal than frequency-domain beamformer because wideband spectrum of noise makes the beamforming image less clear. To avoid the gust effects and enable the location of blast source accurately, this article proposes a new 1-D far-field delay-and-sum (DAS) beamforming method with an attenuate exponential function model for wireless overpressure transient signal. In addition, we design wireless overpressure peak and root-mean-square (rms) directional estimators to assess the performance of the proposed new DAS beamforming method. Furthermore, the effects of the wireless pressure sensor node (WPSN) spacing, the number of WPSNs, and sidelobe level brought from noise on the beamwidth are investigated in the two estimators. The proposed formula is verified by a uniformly spaced linear sensing array, and the results verify the feasibility of the proposed method in blast source localization. This article is conducted to provide new insight into blast source localization algorithm and further open a door for transient blast overpressure source localization scenarios in future.

3D designed battery-free wireless origami pressure sensor

A pressure monitoring structure is a very useful element for a wearable device for health monitoring and sports biomechanics. While pressure sensors have been studied extensively, battery-free functions working in wireless detection have not been studied much. Here, we report a 3D-structured origami-based architecture sensor for wireless pressure monitoring. We developed an architectured platform for wireless pressure sensing through inductor-capacitor (LC) sensors and a monopole antenna. A personalized smart insole with Miura-ori origami designs has been 3D printed together with conductive 3D printed sensors seamlessly. Wireless monitoring of resonant frequency and intensity changes of LC sensors have been demonstrated to monitor foot pressure for different postures. The sensitivity of the wireless pressure sensor is tunable from 15.7 to 2.1 MHz/kPa in the pressure ranges from 0 to 9 kPa and from 10 to 40 kPa, respectively. The proposed wireless pressure-sensing platform can be utilized for various applications such as orthotics, prosthetics, and sports gear.