Real-time Pressure Monitoring Research Articles

P.083 Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept

Background: Surgical resection of vestibular schwannoma (VS) is often curative if gross total resection is achieved, however, it is a delicate procedure with high risk to the facial nerve. With retrosigmoid approach for resection, the head is positioned to maximize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding. Methods: Here, we review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusions: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and potentially other neurosurgical procedures.

Use of jugular venous pressure to optimize outcomes of vestibular schwannoma resection: a review of the literature and proof of concept

Background: Surgical resection of vestibular schwannoma (VS) and other benign posterior fossa tumors is often curative if gross total resection is achieved, however, these lesions pose unique challenges due to their intricate location and proximity to critical structures. Approaches for resection often utilize lateral head rotation and neck flexion in order to optimize the surgical field. However, this may inadvertently occlude cerebral venous drainage, elevating intracranial pressure (ICP) and increasing intraoperative bleeding, potentially increasing the operative risk to patients. Methods: We review relevant literature regarding the effects of head rotation and neck flexion on internal jugular vein (IJV) occlusion and ICP, and highlight the notion that head rotation and flexion may occlude the ipsilateral IJV, increasing ICP. Subsequently, we propose a novel technique using continuous, real-time monitoring of jugular bulb pressure (JBP) to detect obstructions in jugular venous flow and guide optimal head positioning prior to VS resection. Results: As proof of concept, we present a single-patient case in which JBP monitoring was employed to optimize head positioning prior to a VS resection, which shows a significant reduction in JBP compared to traditional positioning. Conclusion: This innovative approach offers promise in enhancing the safety and efficacy of intracranial surgery for VS and other neurosurgical procedures.

Temperature Self-Compensating Intelligent Wireless Measuring Contact Lens for Quantitative Intraocular Pressure Monitoring.

Flexible bioelectronic devices that can perform real-time and accurate intraocular pressure (IOP) monitoring in both clinical and home settings hold significant implications for the diagnosis and treatment of glaucoma, yet they face challenges due to the open physiological environment of the ocular. Herein, we develop an intelligent wireless measuring contact lens (WMCL) incorporating a dual inductor-capacitor-resistor (LCR) resonant system to achieve temperature self-compensation for quantitative IOP monitoring in different application environments. The WMCL utilizes a compact circuitry design, which enables the integration of low-frequency and high-frequency resonators within a single layer of a sensing circuit without causing visual impairment. Mechanically guided microscale 3D encapsulation strategy combined with flexible circuit printing techniques achieves the surface-adaptive fabrication of the WMCL. The specific design of frequency separation imparts distinct temperature response characteristics to the dual resonators, and the linear combination of the dual resonators can eliminate the impact of temperature variations on measurement accuracy. The WMCL demonstrates outstanding sensitivity and linearity in monitoring the IOP of porcine eyes in vitro while maintaining satisfactory measurement accuracy even with internal temperature variations exceeding 10 °C. Overcoming the impact of temperature variations on IOP monitoring from the system level, the WMCL showcases immense potential as the next generation of all-weather IOP monitoring devices.

Preclinical validation of a customized circuit for ex situ uninterrupted cold-to-warm prolonged perfusion of the liver.

Clinical adoption of ex situ liver perfusion is growing. While hypothermic perfusion protects against ischemia-reperfusion injury in marginal grafts, normothermic perfusion enables organ viability assessment and therefore selection of borderline grafts. The combination of hypothermic and normothermic perfusion, known as "cold-to-warm," may be the optimal sequence for organ preservation, but is difficult to achieve with most commercial perfusion systems. We developed an adaptable customized circuit allowing uninterrupted "cold-to-warm" perfusion and conducted preclinical studies on healthy porcine livers and discarded human livers to demonstrate the circuit's efficacy. In collaboration with bioengineers, we developed a customized circuit that adapts to extracorporeal circulation consoles used in cardiovascular surgery and includes a proprietary reservoir enabling easy perfusate change without interrupting perfusion. This preclinical study was conducted on porcine and human livers. Perfusion parameters (pressures, flows, oxygenation) and organ viability were monitored. The customized circuit was adapted to a LivaNova S5® console, and the perfusions were flow-driven with real-time pressure monitoring. Ten porcine liver and 12 discarded human liver perfusions were performed during 14 to 18 h and 7 to 25 h, respectively. No hyperpressure was observed (porcine and human portal pressure 2-6 and 2-8 mm Hg; arterial pressure 10-65 and 20-65 mm Hg, respectively). No severe histological tissue injury was observed (Suzuki score ≤ 3 at the end of perfusion). Seven (70%) porcine livers and five (42%) human livers met the UK viability criteria. The customized circuit and system design enables smooth uninterrupted "cold-to-warm" perfusion not present in current commercial perfusion systems.

Flexible actuation with intrinsic sensing for ram extrusion 3D printing

Conventional actuation mechanisms used in liquid deposition modeling (LDM) technology limit the flow handling capability and the visibility of the printing materials’ properties. This work presents a flexible actuation system with intrinsic sensing for a ram extrusion printhead used in LDM technology. A mathematical model is used to design and simulate the printhead. The experimental results demonstrate the system’s ability to control the extrusion flow in two modes. The pressure control mode is favorable for the flow in a transient state such as flushing. The volumetric control mode provides a constant printed line width with less than 0.1-mm deviation between each tested material (biogel, chocolate fudge, and silicone sealant). A lower standard deviation for printed lines in the volumetric control mode indicates more precise line printing. The system also incorporates real-time monitoring of extrusion pressure and flow rate. The intrinsic capability to detect printing material properties is validated in both simulation and experiment. It provides valuable insights for further optimization of the printing process. The proposed system offers the advantage of improved pressure and flow control as well as the ability to monitor and respond to the properties of printing material.

Application of PZT Nanofiber Flexible MEMS Technology in Human Resource Employment Pressure Management

The advancement of society has led to increasing pressure on employment in human resources. Effectively managing and alleviating this pressure has emerged as an urgent problem to be addressed. This study presents a novel pressure sensor utilizing microelectromechanical systems technology, with the aim of offering a fresh solution for managing employment pressure in the human resource sector. Firstly, this study presents the preparation and characterization of lead zirconate titanate nanofibers, followed by the development of a flexible pressure sensor using microelectromechanical systems technology specifically designed for these fibers. Finally, this study evaluates the performance of the developed pressure sensor. The results revealed that the open circuit output voltage of the sensor peaked at a pressure frequency of 110 Hz, indicating the highest level of response. In addition, it was observed that the open circuit output voltage of the fabricated sensor exhibited fluctuations within the voltage range of –3.8 V to 5.0 V, confirming its ability to precisely respond to variations in external pressure at any given moment. The features of this developed pressure gauge render it an ideal tool for real-time monitoring and evaluation of pressure, thereby possessing wideranging application prospects.

PressureCap: An endoscopic sensor capsule for real-time gastrointestinal pressure monitoring

PressureCap: An endoscopic sensor capsule for real-time gastrointestinal pressure monitoring

Regulating the π–π interactions of copolymer gelators: Effective molecular design of highly stretchable and tough ionogels for wearable ionotronics

The emergence of stretchable ionic conductors has facilitated the development of wearable devices that can perceive changes in their surrounding environment and interpret external stimuli. An example of this is ionic skin, a form of artificial skin that is worn constantly for the real-time monitoring of temperature, pressure, and tension. However, ionic skins are vulnerable to physical damage and stress, which reduces their functionality, performance, and longevity. To obtain mechanically durable ionic skins, the toughness of their constituent ionogels must be improved by increasing their strength and/or stretchability. However, the molecular design and synthesis of these materials remain challenging due to the inherent trade-off between mechanical durability and ionic conductivity. In the present study, we introduced three styrene derivatives containing pendant groups of different sizes to copolymer gelators as ionic liquid (IL)-solvophobic components that form physically crosslinked domains and compared the mechanical and conductivity performance of the resulting ionogels. As the packing density of the styrene decreased, the IL-solvophobic domains became softer and more deformable due to the weaker physical crosslinking via π–π interactions. The optimal ionogel exhibited high stretchability (∼1200 %), excellent toughness (∼3.4 MJ·m−3), and high transparency (∼98 %). The successful use of the optimal ionogel in ionic skin sensors and deformable alternating-current electroluminescent displays demonstrated its broad range of practical applications.

Implementation of a novel thoracostomy tube trainer with real-time feedback

ObjectivesSimulation-based training leads to improved clinical performance but may be influenced by quality and frequency of training. Within simulation training, chest tube insertion remains a challenge as one of the...

Preparation of lignin-containing cellulose nanofibers from walnut shell using deep eutectic solvent for nanotube conductive film

A deep eutectic solvent (DES) was employed to purify cellulose by depolymerizing agricultural waste walnut shells (WS) at 90 ℃ from 1.5 to 3.0 h. The pretreatment achieved an 88.57% delignification rate and yielded 33.62% cellulose solids (CS), with 77.63% cellulose and 13.11% lignin contained in CS. The DES pretreatment exposed functional groups on the surface of cellulose and resulted in a 24.7% increase in crystallinity. Suspension with a homogeneous distribution of lignin-containing cellulose nanofibers (LCNF) was made by ultrasonic dispersing (650 W, 30 min), and the average length of 1406 nm, the ζ-potential of − 17.65 mV. Higher lignin content led to cross-linking effect which produced a heightened degree of entanglement of LCNF while increasing the UV-shielding property and thermal stability. Additionally, LCNF stabilized the dispersion of multi-walled carbon nanotubes (MWCNT) in water, and served as a carrier for MWCNT conductive networks, which showed a tensile strength of 63.86 MPa and a conductivity of 15.63 S/m. The composite film exhibited potential applications in real-time monitoring of pressure sensing.

Retracted: Real-Time Monitoring of Intraocular Pressure in Glaucoma Patients Using Wearable Mobile Medicine Devices.

[This retracts the article DOI: 10.1155/2022/2271937.].

High-porosity thin membrane for high-efficiency capture of rare cells

High efficiency capture of rare cells such as circulating tumor cells (CTCs) in the blood of cancer-patient is challenging for size-based separation methods, because of the heterogeneity of the cells, the presence of a huge number of background cells (red and white blood cells), and the overlap in size of the rare cells and some of the background cells. In this work, we developed a systematic study to evaluate the parametric dependence of rare cell capture efficiency by using model cells. High-porosity and thin membranes with supporting honeycomb microframe are fabricated by using a two-level lithography technique. They are then integrated into a microfluidic device for real-time monitoring of flow-induced transmembrane pressure with a solution with or without cells. Our results show both experimentally and theoretically a great importance of the pore number of the membrane and the flow rate. When more than 80% of pores are clogged by large background cells, the rare cell capture efficiency decreases significantly. Otherwise, a lossless capture is theoretically achievable with a high-porosity and large-area membrane under optimal flow conditions.

Research and Application of HSE Control System for High Consequence Area Water Injection Pipeline

In view of the fact that the safety management technology prevention and control capabilities are weak in the safety management technology such as long operating life, high pipeline operating pressure, large control area, difficulty in detecting abnormal phenomena, slow valve opening and closing speed, and difficulty in quickly handling emergencies in oilfields, the HSE control system of water injection pipelines in high consequence areas is developed and designed with the help of technical means such as Internet of Things and edge gateway computing, which realizes real-time monitoring of water injection pipeline pressure in high consequence areas, remote control of shut-off valves, timely elimination of hidden dangers, and timely control of dangerous situations. Purpose of expeditious disposal. This research project was tested in the field of a branch of a water injection line in a typical high-consequence area. The verification results show that the system has the functions of real-time monitoring of water injection pressure and remote control of shut-off valve, which is of great significance for improving the HSE technical defense system of oilfield and improving the ability of oilfield to deal with emergencies.

Pressure Monitoring in Medium-Voltage Vacuum Interrupters

Innovation in the economy is closely tied to energy development, encompassing the exploration of new energy sources, increased energy production efficiency, and the integration of diverse energy sources for safe and effective supply to industries and households. Outdated energy infrastructure disrupts electricity continuity and hampers economic innovation. Power interruptions lead to higher SAIDI and SAIFI reliability indices. Quality and reliability requirements have sparked interest in enclosed energy devices. Vacuum technology has been pivotal in electrical switchgear insulation and arc-quenching for over four decades. However, the lack of real-time pressure monitoring systems for vacuum equipment, especially enclosed disconnectors, limits their use as isolation connectors. Potential insulation failure poses risks to power line maintenance teams and can lead to unplanned shutdowns, further compromising energy supply quality. This article explores an innovative pressure monitoring system for vacuum interrupters, utilizing fiber optic Bragg grids as a measuring sensor, enabling pressure measurement within the vacuum chamber ranging from 2 × 101 Pa to 5 × 105 Pa.

MEMS Sensor-Glasses Pair for Real-Time Monitoring of Intraocular Pressure

We present a novel implantable MEMS sensor – readout glasses pair towards the real-time monitoring of intraocular pressure. The overall system comprises i) a diffraction grating interferometric MEMS sensor to be embedded in the cornea and ii) readout glasses embedded with a laser diode, miniaturized aspheric lenses, and a CMOS camera. Owing to the abundance of diffracted orders, the proposed intraocular pressure measuring system offers ±8 degrees of eye tilt tolerance during monitoring via the camera. Furthermore, the use of one or multiple reference gratings adjacent to the sensor mitigates the effects of altering optical power (due to eye motion or laser noise) on the sensor. The design of the proposed device is justified with the analytical modeling of diffracted orders from the pressure sensor and ray-tracing simulations of the readout glasses. Through in-vitro measurements, we demonstrated a measurement range of ΔP = 40 mmHg pressure, with an average deflection sensitivity of 4.06 nm/mmHg and a resolution of 2.5 mmHg. With further development, the proposed system can be used for personalized real-time glaucoma monitoring.

Monitoring blood pressure and cardiac function without positioning via a deep learning-assisted strain sensor array.

Continuous and reliable monitoring of blood pressure and cardiac function is of great importance for diagnosing and preventing cardiovascular diseases. However, existing cardiovascular monitoring approaches are bulky and costly, limiting their wide applications for early diagnosis. Here, we developed an intelligent blood pressure and cardiac function monitoring system based on a conformal and flexible strain sensor array and deep learning neural networks. The sensor has a variety of advantages, including high sensitivity, high linearity, fast response and recovery, and high isotropy. Experiments and simulation synergistically verified that the sensor array can acquire high-precise and feature-rich pulse waves from the wrist without precise positioning. By combining high-quality pulse waves with a well-trained deep learning model, we can monitor blood pressure and cardiac function parameters. As a proof of concept, we further constructed an intelligent wearable system for real-time and long-term monitoring of blood pressure and cardiac function, which may contribute to personalized health management, precise and early diagnosis, and remote treatment.

Research and Test on the Device of Downhole Near-Bit Temperature and Pressure Measurement While Drilling

The accurate acquisition of downhole engineering parameters, such as real-time pressure and temperature measurements, plays a crucial role in mitigating drilling risks and preventing accidents. In this study, we present the design of a real-time data acquisition and transmission system for drilling operations. The system utilizes a near-bit measurement method to simultaneously measure downhole parameters, including mud pressure and temperature. By analyzing the pressure and temperature frequencies obtained from a quartz crystal pressure gauge and compensating for temperature effects, accurate pressure values are obtained. The resistance value of a PT1000 sensor is measured, and a second-order fitting is performed using laboratory scale coefficients to determine the temperature values. The data acquisition system employs an advanced microcontroller as the main control chip, along with an A/D conversion chip. Additionally, signal amplification, data storage modules, data transmission modules, and relevant peripheral circuits are designed. The field tests were conducted in the 4605~4620 m well section of well Qing 2-76 in the Yumen Oilfield. The results demonstrate stable transmission signals and accurate decoding, enabling the real-time monitoring of pressure and temperature. The tests yielded favorable outcomes, providing a tangible means to analyze the actual operating conditions of the downhole drill string.

Smart glasses to monitor intraocular pressure using optical triangulation

We present a non-contact and non-invasive gadget towards monitoring intraocular pressure. The pressure-monitoring device is in the form of wearable glasses comprising a laser source, multiple miniaturized lenses and mirrors, a mask for structured illumination of the cornea, and a miniaturized camera. The pressure level is deduced through observing the radius of curvature of the grid pattern on the cornea. We justify our design with analytical modeling, ray tracing and finite element simulations, and experiments on an elastic eye phantom at different tilt angles. The results reveal a pressure measurement resolution of 2.4 mmHg between 0 – 55 mmHg pressure range. The proposed device was further tested on an ex-vivo ovine eye in regards to laser visibility by the camera, at laser safe power levels. With further in-vivo experimentation and development, the proposed gadget could potentially be used in personalized real-time intraocular pressure monitoring during the daytime.

Experimental assessment of cardiovascular physiology in the chick embryo.

High resolution assessment of cardiac functional parameters is crucial in translational animal research. The chick embryo is a historically well-used in vivo model for cardiovascular research due to its many practical advantages, and the conserved form and function of the chick and human cardiogenesis programs. This review aims to provide an overview of several different technical approaches for chick embryo cardiac assessment. Doppler echocardiography, optical coherence tomography, micromagnetic resonance imaging, microparticle image velocimetry, real-time pressure monitoring, and associated issues with the techniques will be discussed. Alongside this discussion, we also highlight recent advances in cardiac function measurements in chick embryos.

Real-Time Continuous Monitoring of Oral Soft Tissue Pressure with a Wireless Mouthguard Device for Assessing Tongue Thrusting Habits.

In orthodontics, understanding the pressure of oral soft tissues on teeth is important to elucidate the cause and establish treatment methods. We developed a small wireless mouthguard (MG)-type device that continuously and unrestrainedly measures pressure, which had previously been unachieved, and evaluated its feasibility in human subjects. First, the optimal device components were considered. Next, the devices were compared with wired-type systems. Subsequently, the devices were fabricated for human testing to measure tongue pressure during swallowing. The highest sensitivity (51-510 g/cm2) with minimum error (CV < 5%) was obtained using an MG device with polyethylene terephthalate glycol and ethylene vinyl acetate for the lower and upper layers, respectively, and with a 4 mm PMMA plate. A high correlation coefficient (0.969) was observed between the wired and wireless devices. In the measurements of tongue pressure on teeth during swallowing, 132.14 ± 21.37 g/cm2 for normal and 201.17 ± 38.12 g/cm2 for simulated tongue thrust were found to be significantly different using a t-test (n = 50, p = 6.2 × 10-19), which is consistent with the results of a previous study. This device can contribute to assessing tongue thrusting habits. In the future, this device is expected to measure changes in the pressure exerted on teeth during daily life.