Search

A freehand three-dimensional (3D) ultrasound system is a method of acquiring images using a 3D ultrasound probe or conventional two-dimensional (2D) ultrasound probe to give a 3D visualization of an object inside the body. Ultrasounds are used extensively in clinical applications since they are advantageous in that they do not bring dangerous radiation effects and have a low cost. However, a probe calibration method is needed to transform the coordinate position into a 3D visualization display, especially for image-guided intervention. The current ultrasound probe calibration system usually uses the numerical regression method for the N-wire phantom, which has problems in accuracy and reliability due to nonlinear point scattered ultrasound image data. Hence, a method for ultrasound probe positional calibration of single-wire phantom using the Levenberg-Marquardt algorithm (LMA) was proposed to overcome this weakness. This experiment consisted of an optical tracking system setup, a 2D ultrasound probe with marker, an ultrasound machine, and a single-wire object in a water container equipped with a marker. The position and orientation of the marker in a 2D ultrasound probe and the marker in the water container were tracked using the optical tracking system. A 2D ultrasound probe was equipped with a marker connected wirelessly using an optical tracking system to capture the single-wire object. The resulting sequences of 2D ultrasound images were reconstructed and visualized into 3D ultrasound images using three transformations, ultrasound beam to ultrasound probe’s marker, single-wire phantom position to container’s marker, and the 3D visualization transformation. The LMA was used to determine the best optimization parameters for determining the exact position and representing that 3D visualization. The experiment result showed that the lowest mean square error (MSE), rotation error, and translation error were 0.45 mm, 0.25°, and 0.3828 mm, respectively.

The aim of the present study was to determine the reliability and differences between three fascicle length (FL) estimation methods when utilizing a 10-cm ultrasound (US) probe. Thirteen males (24.1 ± 3.8 years, 79.3 ± 14 kg, 179 ± 6.6 cm) participated. Bicep femoris long head (BFLH) US images were collected on two separate occasions. Three previously established extrapolation methods were utilized. Near-perfect reliability was observed for all methods. Criterion estimation resulted in a significant, trivial (p = 0.016,g = 0.17) increase in FL compared to the basic trigonometry equation with non-significant, trivial increase (p = 0.081,g = 0.10) between the criterion and partial measure method. The partial measure method was not significantly or meaningfully greater than the basic trigonometry method (p = 0.286,g = 0.08). Both alternative methods demonstrated unacceptable LOA (>5%), with heteroscedasticity. All methods of extrapolation are reliable and could be used over time. However, as methods are not comparable, there could be a rationale to utilize underestimated results to ensure a degree of cushioning.

Abstract Objectives To observe change in economy of 9 ultrasound probe movement metrics among internal medicine trainees during a 5-day training course in cardiac point of care ultrasound (POCUS). Methods We used a novel probe tracking device to record nine features of ultrasound probe movement, while trainees and experts optimized ultrasound clips on the same volunteer patients. These features included translational movements, gyroscopic movements (titling, rocking, and rotation), smoothness, total path length, and scanning time. We determined the adjusted difference between each trainee’s movements and the mean value of the experts’ movements for each patient. We then used a mixed effects model to trend average the adjusted differences between trainees and experts throughout the 5 days of the course. Results Fifteen trainees were enrolled. Three echocardiographer technicians and the course director served as experts. Across 16 unique patients, 294 ultrasound clips were acquired. For all 9 movements, the adjusted difference between trainees and experts narrowed day-to-day (p value

Abstract Medical imaging-based triage is a critical tool for emergency medicine in both civilian and military settings. Ultrasound imaging can be used to rapidly identify free fluid in abdominal and thoracic cavities which could necessitate immediate surgical intervention. However, proper ultrasound image capture requires a skilled ultrasonography technician who is likely unavailable at the point of injury where resources are limited. Instead, robotics and computer vision technology can simplify image acquisition. As a first step towards this larger goal, here, we focus on the development of prototypes for ultrasound probe securement using a robotics platform. The ability of four probe adapter technologies to precisely capture images at anatomical locations, repeatedly, and with different ultrasound transducer types were evaluated across more than five scoring criteria. Testing demonstrated two of the adapters outperformed the traditional robot gripper and manual image capture, with a compact, rotating design compatible with wireless imaging technology being most suitable for use at the point of injury. Next steps will integrate the robotic platform with computer vision and deep learning image interpretation models to automate image capture and diagnosis. This will lower the skill threshold needed for medical imaging-based triage, enabling this procedure to be available at or near the point of injury.

This article introduced the design and application of the ultrasound probe holder for ultrasound-guided venipuncture. The ultrasound probe holder has been designed to hold a variety of probes in different angles, and to provide more comfort with less fatigue for the operator. The components of the probe holder can be dismantled for cleaning or sterilization. (本文介绍一种用于超声引导静脉穿刺的超声探头固定装置的设计与应用。该装置操作简便, 能够灵活调整并固定超声探头, 提高操作者舒适度, 且可拆卸进行清洗或消毒。)

Objectives: This study aimed to develop an ultrasound-guided high-intensity-focused ultrasound (USgHIFU) probe for arterial sonication and to evaluate vascular contraction., Methods: The USgHIFU probe comprised two confocal spherical transducers for sonication and a US color Doppler flow imaging probe for guidance. A vessel-mimicking phantom was sonicated in two directions. In the vascular radial direction, an isolated rabbit aorta embedded in ex vivo pork liver was sonicated at different acoustic powers (245 and 519 W), flow rates (25, 30, and 50 mL/minute), and sonication energies (519, 980, and 1038 J). Changes in the postsonication vessels were evaluated using US imaging, microscopic observation, and histopathological analysis., Results: Beam focusing along the vascular radial direction caused significant deformation of both tube walls (n = 4), whereas focusing along the axial direction only affected the contraction of the anterior wall (n = 4). The contraction index (D c ) of the vessel sonicated at 245 W and 980 J was 56.2 ± 9.7% (n = 12) with 25 mL/minute. The D c of the vessel sonicated at 519 W and 1038 J was 56.5 ± 7.8% (n = 17). The D c of the vessel sonicated at 519 J total energy was 18.3 ± 5.1% (n = 12)., Conclusion: The developed USgHIFU probe induced greater vascular contractions by covering a larger area of the vessel wall in the radial direction. Sonication energy affects vascular contraction through temperature elevation of the vessel wall. When the acoustic power was high, an increase in acoustic power, even with comparable sonication energy, did not result in greater vessel contraction., (© 2024 American Institute of Ultrasound in Medicine.)

The need for continuous monitoring of cardiorespiratory activity, blood pressure, bladder, muscle motion analysis, and more, is pushing for research and development of wearable ultrasound devices. In this context, there is a critical need for highly configurable, energy-efficient wearable ultrasound systems with wireless access to raw data and long battery life. Previous exploratory works have primarily relied on bulky commercial research systems or custom-built prototypes with limited and narrowly-focused field applicability. This paper presents TINYPROBE, a novel multi-modal wearable ultrasound platform. TINYPROBE integrates a 32-channel ultrasound RX/TX frontend, including TX beamforming (64 V pp excitations, 16 delay profiles) and analog-to-digital conversion (up to 30 Msps, 10 bit), with a WiFi link (21.6 Mbps, UDP), for wireless raw data access, all in a compact (57 × 35 × 20 mm) and lightweight (35 g) design. Employing advanced power-saving techniques and optimized electronics design, TINYPROBE achieves a power consumption of < 1W for imaging modes (32 ch., 33 Hz) and < 1.3W for high-PRF Doppler mode (2 ch., 1400 Hz). This results in a state-of-the-art power efficiency of 44.9 mW/Mbps for wireless US systems, ensuring multi-hour operation with a compact 500 mAh Li-Po battery. We validate TINYPROBE as a versatile, general-purpose wearable platform in multiple in-vivo imaging scenarios, including muscle and bladder imaging, and blood flow velocity measurements.

Ultrasound probe quality assurance is an underserved and underregulated area in medical imaging. While several testing methods exist, their availability and adoption remains varied, and the frequency of testing is often insufficient. Here we aimed to conduct a user-driven simple and rapid probe quality testing approach and to evaluate its rationale.Testing was based on physical examination of probe integrity (all probes) and in-air reverberation check (for curvilinear and linear array probes), findings, as well as probe age were registered. Prior to assessment, probes were divided into a high-risk vs. a low-risk category, based on the perceived risk of probe damage as a result of the typical application (e.g., non-invasive vs. interventional, inpatient vs. point-of-care).17.4% of the low-risk and 31.4% of high-risk probes demonstrated physical wear or damage. Reverberation artifacts were significantly more frequent (68%) in the high-risk category vs. the low-risk one (29.4%). Probes with either physical or reverberation faults were significantly older on average.The simple, rapid investigational technique uncovered an alarming percentage of probe damage or faults. It also identified immediately solvable technical issues (e.g., poor cable contact mimicking dropout). High-risk probe usage resulted in an increased rate of reverberation errors and physical damage. Risk-based, frequent rapid observational testing of ultrasound probes could substantially improve both diagnostic quality and patient safety., Competing Interests: The author of the manuscript declares relationships with the following companies at the time of manuscript submission: Samsung Medison Co Ltd (invited speaker of past events - unrelated to the topic of the present study). Radiopaedia.org (editor, pro bono commitment with no financial compensation)., (Thieme. All rights reserved.)

This paper presents a quantitative index introduced, ‘clarity,’ which can address both the ultrasound probe's brightness and full contact states to indicate ultrasound image quality for the robotic ultrasound system. Furthermore, it evaluates its performance through an experiment, a comparative analysis, and a questionnaire. The index is calculated based on pixel statistics within the predefined region of interest. Experimental validation is conducted by implementing a robotic ultrasound system and performing experiments using two phantoms. Notably, the Results demonstrate the distinction of the visible difference in ultrasound images but also show that it is hard to classify the tiny difference. Additionally, a questionnaire was carried out to ask about the recognition of good image quality. The opinions are the same trends and patterns. The 53.4 clarity value was determined from the answers as the boundary between good and bad-quality images. The experiment results, and questionnaire findings suggest that the proposed clarity index could be a reliable tool for evaluating ultrasound image quality in robotic systems, offering insights for improving diagnostic accuracy and efficiency. This research provides a clear framework for assessing ultrasound image quality in robotic applications, paving the way for advancements in the efficacy and precision of ultrasound imaging techniques. [ABSTRACT FROM AUTHOR]

Ultrasound imaging is extensively used by both practitioners and researchers in assessing muscle thickness (MT); however, its use in the field is constrained by the transportability of stationary devices. New portable ultrasound probes pose as a cost-effective and transportable alternative for field-based assessments. This study evaluated the concurrent validity of a portable probe (Lumify) against a laboratory-based device (Vivid S5) in measuring MT. Eighteen participants (nine males and nine females) visited the laboratory and their MT measurements were collected using each device at five different sites (anterior and posterior arm, anterior and posterior thigh, and posterior lower leg). Bland-Altman plots (systematic and proportional bias, random error, and 95% limits of agreement), Pearson's product-moment correlation coefficient (r), and paired samples t-tests with Cohen's d effect sizes (ES) were used to assess the concurrent validity of the Lumify device. Systematic bias was low at all sites ( ≤ 0.11 cm) while proportional bias was detected only at the posterior lower leg (r 2  = 0.217 [r = 0.466]). The difference in MT between devices was significant only at the anterior thigh (p < 0.05); however, ES for all sites were considered trivial (ES ≤ 0.131). Linear associations were found between the devices at each site of measurement (r ≥ 0.95). These results highlight that the Lumify probe can be used interchangeably with the Vivid S5 for MT measurements, providing practitioners and researchers with a more cost-effective and portable alternative for field-based assessments., (© 2024 The Author(s). Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd on behalf of Scandinavian Society of Clinical Physiology and Nuclear Medicine.)