Study objective: The three-dimensional shape of the ultrasound beam produces a thicker scan plane than most users assume. Viewed longitudinally, a needle placed lateral to a vessel just outside the central scanning plane can be displayed incorrectly in the ultrasound image as if placed intravascularly. This phenomenon is called the beam width artefact, also known as the elevation or slice thickness artefact. The goal of this study was to demonstrate the potential negative effect of the beam width artefact on the performance of in-plane ultrasound- guided vascular access procedures, and to provide a solution. Design: Randomized, double-blinded study Setting: Department of anaesthesiology and intensive care of a teaching hospital Participants: 31 experienced (anesthesiologists and intensivists) and 36 inexperienced (anesthetic nurses) ultrasound users Interventions: We developed an acoustic lens that narrows the scan plane to reduce the beam width artefact. The lens was tested in a simulated vascular access study. Measurements: The primary endpoint was first pass success. Secondary endpoints were the number of punctures and needle withdrawals, procedure time, needle visibility and operator satisfaction. Main results: First pass success was highly enhanced using the acoustic lens, with a success rate of 92.5% versus 68.7% without the lens (difference 23.8, 95% confidence interval 11.0–35.3, p <0.001). The total number of punctures needed to obtain intravenous access was also reduced using the lens (1.10 versus 1.38, difference 0.27, 95% CI 0.11–0.43, p =0.002). Procedure time, needle withdrawals, needle visibility and satisfaction were similar. Both inexperienced and experienced users benefited from the acoustic lens. Conclusions: The beam width artefact has a significant effect on the performance of ultrasound-guided needle- based procedures. The efficacy of in-plane superficial vascular access procedures can be enhanced by narrowing the imaging plane using an acoustic lens.
MULTIFILE
Echo intensity determined by muscle ultrasound has been proposed as an efficient method for the assessment of muscle quality. The influence of changing ultrasound parameter settings on echo intensity values was assessed using a standardized approach. In this repeated measures cross-sectional study, sixteen repeated scans of rectus femoris, gracilis, and rectus abdominis were taken in 21 middle-aged persons with a portable Mindray M7 premium ultrasound machine equipped with a linear 5.0–10.0 MHz transducer. The settings of three parameters were fixed: gain, depth, and frequency. The settings of the following adjustable parameters were changed over their entire range: dynamic range, gray map, line density, persistence, and IClear. Repeated measures analyses were performed to evaluate the effect of changing the settings on echo intensity values. In all three muscles, dynamic range, gray map, and IClear correlated significantly (rrm-values ranging between −0.86 and 0.45) with echo intensity. In all three muscles, the echo intensity values differed significantly across the dynamic range (p < 0.013), gray map (p < 0.003), and IClear (p < 0.003). In middle-aged subjects, echo intensity values of lower limb and trunk muscles are significantly related to ultrasound parameters and significantly differ across their respective setting range. For the assessment of muscle quality through ultrasound, it is suggested to fix parameter settings within their midrange in order to minimize the effect of setting-dependent factors on EI values.
This review evaluates the reliability and validity of ultrasound to quantify muscles in older adults. The databases PubMed, Cochrane, and Cumulative Index to Nursing and Allied Health Literature were systematically searched for studies. In 17 studies, the reliability (n = 13) and validity (n = 8) of ultrasound to quantify muscles in community-dwelling older adults (≥60 years) or a clinical population were evaluated. Four out of 13 reliability studies investigated both intra-rater and inter-rater reliability. Intraclass correlation coefficient (ICC) scores for reliability ranged from -0.26 to 1.00. The highest ICC scores were found for the vastus lateralis, rectus femoris, upper arm anterior, and the trunk (ICC = 0.72 to 1.000). All included validity studies found ICC scores ranging from 0.92 to 0.999. Two studies describing the validity of ultrasound to predict lean body mass showed good validity as compared with dual-energy X-ray absorptiometry (r(2) = 0.92 to 0.96). This systematic review shows that ultrasound is a reliable and valid tool for the assessment of muscle size in older adults. More high-quality research is required to confirm these findings in both clinical and healthy populations. Furthermore, ultrasound assessment of small muscles needs further evaluation. Ultrasound to predict lean body mass is feasible; however, future research is required to validate prediction equations in older adults with varying function and health.
MSEs have encountered limitations while pushing the limits of catheter tip sensors performance. The limitations summarized: - sensors are not immune to electrical signal noise, cross talk, and EM fields; - sensors are not immune to high magnetic fields, i.e. not suitable for MR imaging; - extending the amount of sensors on the catheter tip is limited due to cluttering of wires. A fundamentally different approach using integrated optics is chosen for developing a new generation catheter sensors. The complexity of the design and production problems represents a knowledge gap, that can be bridged in the proposed consortium. This project consists of four work packages, total duration two years, subdivided into four phases. A crucial deliverable of the project is presented at the end of phase IV (WP4), namely a demonstrator integrating pressure and temperature sensors (obtained from WP1) with a newly designed readout system. This system is modularly extendable for future catheter tip sensors. In WP1, pressure- and temperature sensors are developed using two design approaches. In WP2 the influence of downscaling an ultrasound MZI device is explored and the microfabrication process parameters are studied. An additional goal of WP2 is to find the most suitable method for measuring lactate concentration. Among the deliverables five manuscripts: manuscript 1 includes simulations and measurements of the developed pressure and temperature sensors, manuscript 2 answers the question: can a grated fiber be used for measuring pressure and temperature on a tip? Manuscript 3 answers the question: which method is most suitable for measuring lactate concentration on a tip? Manuscript 4 answers the question: does a US intensity detector fit on a catheter tip while obeying the LoR? Manuscript 5 describes the performance of the demonstrator (Phase IV), i.e. integration of T/P sensing with a modular read out system.
The application of sensors in water technology is a crucial step to provide broader, more efficient and circular systems. Among the different technologies used in this field, ultrasound-based systems are widely used, basically to generate energy peaks for cell lysis and particle separation. In this work, we propose the adaptation of an ultrasound system to monitor the concentration of solid particles in wastewater treatment plants settlers as well as to indicate sludge level (real time). A similar sensor was developed and tested in another project which operated successfully at solids concentration up to 1% in UASB reactors. Such measurements are nowadays obtained via time-consuming physical (solids) analysis, which can compromise the efficiency of the settlers and the quality of the effluent. The present project proposes an improved version of the sensor, which will combine solids concentration monitoring and sludge level detection. The defined targets have the intention to make a sensor with a much broader range of applications, been suitable not only for UASB reactors but also to settler and aerobic tanks. The project is a cooperation between the Water Technology lectoraat of NHL Stenden University of Applied Sciences, two SME’s - YNOVIO B.V. and Lamp-ion B.V. - and the INCT group (Brazil). If proven feasible, the concept can generate a big business market to the involved Dutch partners as well as favor the automation of WWTP in the Netherlands, Brazil and around the world.
The ongoing debate over the use of fossil fuels, particularly diesel, in engines due to concerns about global climate change has prompted the exploration of alternative propulsion methods and fuels. Despite various proposed alternatives, diesel engines continue to play a vital role in the global market [1]. This discussion has spurred innovations aimed at enhancing the performance and sustainability of diesel engines, including the utilization of biodiesel mixtures, synthetic fuels, and water-in-diesel emulsions (W/D emulsions) [2-5]. Scientific evidence indicates that the presence of water in water-diesel emulsions can improve engine performance and reduce emissions, such as particulate matter and NOx [6,7]. This performance enhancement is attributed to the phenomenon of micro-explosion, or secondary atomization, caused by the differing boiling points of water and diesel [8]. The rapid temperature increase during fuel injection leads to the explosive vaporization of dispersed water droplets, breaking up the diesel emulsion into smaller droplets and resulting in a shorter combustion time. Various processes, including membrane emulsification, ultrasound emulsification, and high shear stirring, are employed to create these emulsions, often necessitating the use of surfactants for stability [9]. This research proposes a two-fold approach: firstly, the use of Electrohydrodynamic Atomization (EHDA, or electrospray) to create stable water-diesel emulsions. Secondly, the employment of magnetic fields in treating both diesel and water-diesel emulsions. EHDA is already used in several applications, such as drug encapsulation, bioencapsulation, thin film coatings and is also known for its ability to form stable emulsions. [10-13]. For the second approach, it has been shown that nanobubbles can be formed [17] and stabilized due to the electric charging action of magnetic fields [18]. We hypothesize that the charged bubbles can further stabilize the diesel-water emulsion and also enhance the explosive evaporation due to the additional Coulomb forces in play.
