Ultrasound Measurements Research Articles

Application of prophylactic flow restriction in brachiocephalic arteriovenous fistulas

To investigate the effects of prophylactic flow restriction for brachiocephalic arteriovenous fistula on postoperative high-flow-related complications and patency rate in patients undergoing hemodialysis. Clinical data of patients with end-stage renal disease who underwent brachiocephalic arteriovenous fistula surgery for hemodialysis from February 2017 to May 2022 in Department of Nephrology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine were retrospectively analyzed. During surgery, a 4-5 mm vascular suture loop was placed around the vein near the anastomosis as a flow restriction device in 43 patients (flow restriction group), while 42 patients did not receive the prophylactic flow restriction ring (control group). All patients were followed up for 1 to 5 years. The incidence rates of complications related to the hemodialysis access pathway, including distal ischemia syndrome, the formation of arteriovenous fistula aneurysms, thrombus, high-flow congestive heart failure, anastomosis of the vein within 1 cm of the anastomosis and cephalic arch stenosis, were compared between the two groups. The natural blood flow rate of the arteriovenous fistula, anastomosis size, the internal diameter of the vein near the anastomosis, primary patency rate, assisted primary patency rate, and secondary patency rate of the arteriovenous fistula, were also evaluated and compared between the two groups. Logistic regression analysis was used to investigate the factors affecting arteriovenous fistula patency rates, as well as the impact of the flow-restricting ring on postoperative factors. Ultrasound measurements showed that the internal diameter of the vein at the site of the flow restriction ring in the flow restriction group was (3.7±0.6) mm at three months postoperatively, which was significantly smaller than the internal diameter of the narrowest part of the vein near the anastomosis in the control group [(4.1±1.0) mm, t=－2.416, P<0.01]. The postoperative anastomotic diameter and natural blood flow rate of the arteriovenous fistula in the flow restriction group were both significantly lower than those in the control group (both P<0.05). Furthermore, the incidence rates of various complications in the flow restriction group were significantly lower than those in the control group (all P<0.05). At 6, 12, and 24 months postoperatively, the primary patency rate and assisted primary patency rate in the flow restriction group were significantly higher than those in the control group (both P<0.05), while there was no significant difference in secondary patency rates between the two groups (P>0.05). Binary logistic regression analysis indicated that age, diabetes, and natural blood flow rate of the arteriovenous fistula at 3 months postoperatively were independent risk factors for primary patency rate, while the flow restriction for brachiocephalic arteriovenous fistula was an independent protective factor for primary patency rate (P<0.01 or P<0.05). The application of flow restriction was negatively correlated with anastomotic diameter at 6 and 12 months, natural arteriovenous fistula blood flow, and the incidence rates of cephalic arch stenosis and aneurysm formation (all P<0.05). The prophylactic constriction during brachiocephalic arteriovenous fistula surgery in patients undergoing hemodialysis can limit the size of the anastomosis and postoperative arteriovenous fistula blood flow, reducing complications such as cephalic arch stenosis and high-flow heart failure, and increasing primary patency rates of arteriovenous fistula and delay the reintervention of the fistula.

Clinical utility of extracorporeal shock wave therapy in restoring hand function of patients with nerve injury and hypertrophic scars due to burns: A prospective, randomized, double-blinded study.

Joint contractures and nerve injuries are common after hand burns. Extracorporeal shock wave therapy (ESWT) is effective not only for the regeneration of various tissues, including scar tissues, but also for reducing pain and pruritus in patients with burns. Researchers have attempted to explore the effects of ESWT on hand dysfunction caused by nerve injury following burns. We evaluated the effects of ESWT (compared to sham stimulation) on hands with nerve injury and hypertrophic scars and thereby on hand function. The current study was a double-blind randomized controlled trial involving 120 patients. The ESWT parameters were as follows: energy flux density, 0.05-0.30mJ/mm2; frequency, 4Hz; 1000 to 3000 impulses per treatment; and 12 treatments, one/week for 12 weeks. Outcome measures were as follows: 10-point visual analog scale for pain, Jebsen-Taylor hand function test, grip strength, Purdue Pegboard test, ultrasound measurement of scar thickness, and skin characteristics before and immediately after 12 weeks of treatment. No significant inter-group difference was noted after the initial evaluation (P>0.05). More significant improvements were found in the ESWT group than in the sham group in terms of the VAS score (P=0.004), extension ROMs of hand joints (P=0.02), the JTT scores (writing, small, and light) (P<0.001, P<0.001, and P=0.002), and skin characteristics (melanin, skin distensibility, and biologic skin elasticity) (P=0.004, P<0.001, and P<0.001). Other measured outcomes did not differ between the two groups after the treatment. We identified the clinically beneficial effects of ESWT in promoting hand function, improving scarring, and alleviating scarring-related pain, thereby highlighting its advantages in improving hand function that has been impaired due to nerve injury and hypertrophic scars after burns.

Predictive Value of Diaphragm Muscle Ultrasound for Ventilator Weaning Outcomes After Cervical Spinal Cord Injury: A Retrospective Case Series.

Neuromuscular respiratory failure after cervical spinal cord injury (cSCI) can lead to dependence on an invasive mechanical ventilator. Ventilator-free breathing after cSCI is associated with improved morbidity, mortality, and quality of life. We investigated the use of diaphragm muscle ultrasound to predict ventilator weaning outcomes after cSCI. This is a retrospective case series conducted at a university-affiliated freestanding inpatient rehabilitation facility. We identified patients with cSCI who had a tracheostomy and were dependent on an invasive mechanical ventilator at the time of admission to inpatient rehabilitation. A diaphragm muscle ultrasound was performed, which included measurements of the thickness of the diaphragm and a calculation of the thickening ratio (TR), which reflects diaphragm muscle contraction. The primary outcome measure was the need for mechanical ventilation at time of discharge from the inpatient rehabilitation facility. Successful ventilator weaning was defined as either daytime or full 24-hour ventilator-free breathing. Of the 21 patients enrolled, 11 (52%) were able to wean successfully (partially or fully) from the ventilator. Of the ultrasound measurements that were taken, the TR was the optimal predictor for ventilator weaning outcomes. A threshold of TR ≥ 1.2 as the maximum hemidiaphragm measurement had a sensitivity of 1.0 and specificity of 0.90 for predicting ventilator weaning. Normal diaphragm contractility (TR ≥ 1.2) as determined by diaphragm muscle ultrasound is a strong positive predictor for successful ventilator weaning in patients with cSCI. Utilizing diaphragm ultrasound, rehabilitation physicians can set precision rehabilitation goals regarding ventilator weaning for inpatients with respiratory failure after cSCI, potentially improving both outcomes and quality of life.

Role of Inflammatory Markers and Doppler Parameters in Late-Onset Fetal Growth Restriction: A Machine-Learning Approach.

This study evaluates the association of novel inflammatory markers and Doppler parameters in late-onset FGR (fetal growth restriction), utilizing a machine-learning approach to enhance predictive accuracy. A retrospective case-control study was conducted at the Department of Perinatology, Ministry of Health Etlik City Hospital, Ankara, from 2023 to 2024. The study included 240 patients between 32 and 37 weeks of gestation, divided equally between patients diagnosed with late-onset FGR and a control group. We focused on novel inflammatory markers-systemic immune-inflammation index (SII), systemic inflammatory response index (SIRI), and neutrophil-percentage-to-albumin ratio (NPAR)-and their correlation with Doppler parameters of umbilical and uterine arteries. Machine-learning algorithms were employed to analyze the data collected, including demographic, neonatal, and clinical parameters, to develop a predictive model for FGR. The machine-learning model, specifically the Random Forest algorithm, effectively integrated the inflammatory markers with Doppler parameters to predict FGR. NPAR showed a significant correlation with FGR presence, providing a robust tool in the predictive model (Accuracy 77%, area under the curve [AUC] 0.851). In contrast, SII and SIRI, while useful, did not achieve the same level of predictive accuracy (Accuracy 75% AUC 0.818 and Accuracy 73% AUC 0.793, respectively). The model highlighted the potential of combining ultrasound measurements with inflammatory markers to improve diagnostic accuracy for late-onset FGR. This study illustrates the efficacy of integrating machines with traditional diagnostic methods to enhance the prediction of late-onset FGR. Further research with a larger cohort is recommended to validate these findings and refine the predictive model, which could lead to improved clinical outcomes for affected pregnancies. ClinicalTrials.gov identifier: NCT06372938.

Comparative Evaluation of UAB and NKF-KDOQI Criteria for Predicting Unassisted Arteriovenous Fistula Maturation Using Postoperative Ultrasound Measurements

Comparative Evaluation of UAB and NKF-KDOQI Criteria for Predicting Unassisted Arteriovenous Fistula Maturation Using Postoperative Ultrasound Measurements

Penile curvature severity in patients with Peyronie's disease does not correlate with dynamic color doppler duplex ultrasound parameters: findings from a real-life cross-sectional study.

There is inconsistent data regarding the possible inaccuracies in dynamic penile color Doppler duplex ultrasound (CDDU) measurements in men with penile curvature because of Peyronie's disease (PD). We sought to explore the relationship between the degree of penile curvature and CDDU parameters in men with PD. Comprehensive data from 154 consecutive men presenting with PD as their primary complaint at a single academic center were prospectively collected and analyzed. All men underwent CDDU. Penile curvature was measured using a goniometer at time of maximum erection during CDDU. Patients were grouped based on CDDU parameters into-normal (average peak systolic velocity [PSV] ≥ 35cm/s and resistance index [RI] ≥ 0.85) and pathological CDDU (average PSV<35cm/s and/or RI<0.85). Descriptive statistics was used to compare the two subcohorts. Linear regression models were fitted to explore the association between the degree of penile curvature and dynamic CDDU parameters. Overall, the median interquartile range (IQR) age was 56 (48-63) years. The median (IQR) PSV and degree of penile curvature were 48.8cm/s (37.9-58.5) and 40 degrees (30-60), respectively. At CDDU, the degrees of penile curvature were as follows: 10-30 degrees in 63 (40.9%) men, 30-70 degrees in 70 (45.5%) men, and 70-90 degrees in 21 (13.6%) men, respectively. Of all, 116 (75.3%) patients showed a PSV>35cm/s and RI ≥ 0.85. Patients with pathologic vs. normal CDDU parameters did not differ in median (IQR) curvature (32.5° [30°-58.7°] vs. 40° [30°-65°], p=0.5) or in the distribution across curvature range groups. Linear regression analysis revealed that the degree of penile curvature did not significantly correlate with PSV at CDDU (coefficient: 0.06, p=0.3). Our study confirms the lack of a significant correlation between the severity of penile curvature and CDDU parameters in men presenting with PD. These findings emerge to be relevant in terms of a more accurate management work-up for PD patients and hold insightful medicolegal implications and in the real-life setting.

Development of an ultrasound-based metric of muscle functional capacity for use in patients with neuromuscular disease.

Spinal muscular atrophy (SMA) and Duchenne muscular dystrophy (DMD) are progressive neuromuscular disorders characterized by severe muscle weakness and functional decline (Pillen et al., Muscle Nerve 2008; 37(6):679-693). With new therapeutics, objective methods with increased sensitivity are needed to assess muscle function. Ultrasound imaging is a promising approach for assessing muscle fat and fibrosis in neuromuscular disorders. This study builds on prior work by combining ultrasound-based measurements of muscle size, shape, and quality, relating these measures to muscle strength, and proposing a multivariable image-based estimate of muscle function. Maximum voluntary elbow flexion torque of 36 participants (SMA, DMD, and healthy controls) was measured by hand-held dynamometry and elbow flexor muscles were imaged using ultrasound. Muscle size (cross-sectional area, maximum Feret diameter or width, and thickness), quality (echogenicity, texture anisotropy index), and cross-sectional shape (diameter ratio) were measured. Multivariable regression was used to select ultrasound measurements that predict elbow flexion torque. Significant differences were observed in muscle size (decreased), shape (thinned), and quality (decreased) with increased disease severity and compared to healthy participants. CSA (brachioradialis R2 = 0.51), maximum Feret diameter (biceps R2 = 0.49, brachioradialis R2 = 0.58) and echogenicity (brachioradialis R2 = 0.61) were most correlated with torque production. Multivariable regression models identified that muscle size (CSA, maximum Feret diameter) and quality (echogenicity) were both essential to predict elbow flexion torque (R2 = 0.65). A multivariable approach combining muscle size and quality improves strength predictions over single variable approaches. These methods present a promising avenue for the development of sensitive and functionally relevant biomarkers of neuromuscular disease.

Reliability and Validity of Ultrasound in Identifying Anatomical Landmarks for Diagnosing A2 Pulley Ruptures: A Cadaveric Study.

Background/Objectives: Rock climbing is becoming more popular, leading to an increased focus on diagnosing and treating related injuries. Finger pulley and flexor tendon injuries are common among climbers, with the A2 pulley being the most frequently affected. High-resolution ultrasound (US) is the preferred method for detecting pulley injuries. This study aimed to determine the reliability and validity of US in identifying anatomical landmarks for diagnosing A2 pulley ruptures. Methods: This study was cross-sectional, involving 36 fingers from 4 cadaver arms. A Canon Aplio i800 US machine was used to measure two anatomical landmarks: the midpoint of the proximal phalanx and the distal edge of the A2 pulley. For the first anatomical landmark, the length of the proximal phalanx (PP distance), and for the second landmark, the distance between the distal edges of the proximal phalanx and the A2 pulley ("A" distance), were measured. Measurements were performed by two sonographers and compared to a digital caliper measurement taken post-cadaver dissection. Observers were blinded during measurements to ensure unbiased results. Results: Overall PP distance measured by US (O1: 37.5 ± 5.3 mm, O2: 37.8 ± 5.4 mm) tended to be shorter than caliper measurements (O3: 39.5 ± 5.5 mm). The differences between sonographers were minimal, but larger when compared to caliper measurements. High reliability for PP distance measurement was observed, especially between sonographers, with an ICC average of 0.99 (0.98, 1.00). However, reliability was lower for the "A" distance, with significant differences between US and caliper measurements. Regarding validity, US measurements were valid when compared to caliper measurements for PP distance, but not as reliable for the "A" due to wider confidence intervals. While US can substitute caliper measurements for PP distance (LR, Y:O2, X:O3, -0.70 (-3.28-1.38), 0.98 (0.93 ± 1.04)), its validity for "A" distance is lower (LR, Y:O2, X:O3, -2.37 (-13.53-4.83), 1.02 (0.62-1.75)). Conclusions: US is a reliable and valid tool in identifying anatomical landmarks for diagnosing A2 pulley ruptures, particularly for detecting the midpoint of the proximal phalanx. This is important to differentiate between complete and partial A2 pulley tears. However, the measurement of the "A" distance requires further refinement. These findings support efforts to standardize US examination protocols and promote consensus in diagnostic methodology, though further research is needed to address the remaining challenges.

Non-Invasive Characterization of Different Saccharomyces Suspensions with Ultrasound.

In fermentation processes, changes in yeast cell count and substrate concentration are indicators of yeast performance. Therefore, monitoring the composition of the biological suspension, particularly the dispersed solid phase (i.e., yeast cells) and the continuous liquid phase (i.e., medium), is a prerequisite to ensure favorable process conditions. However, the available monitoring methods are often invasive or restricted by detection limits, sampling requirements, or susceptibility to masking effects from interfering signals. In contrast, ultrasound measurements are non-invasive and provide real-time data. In this study, the suitability to characterize the dispersed and the liquid phase of yeast suspensions with ultrasound was investigated. The ultrasound signals collected from three commercially available Saccharomyces yeast were evaluated and compared. For all three yeasts, the attenuation coefficient and speed of sound increased linearly with increasing yeast concentrations (0.0-1.0 wt%) and cell counts (R2 > 0.95). Further characterization of the dispersed phase revealed that cell diameter and volume density influence the attenuation of the ultrasound signal, whereas changes in the speed of sound were partially attributed to compositional variations in the liquid phase. This demonstrates the ability of ultrasound to monitor industrial fermentations and the feasibility of developing targeted control strategies.

Evaluation of masticatory muscles in patients with different sagittal direction skeletal anomalies by ultrasonography and ultrasonographic elastography.

The aim of this study was to evaluated the masseter, anterior digastric and geniohyoid muscles of individuals with similar growth and developmental periods but different sagittal skeletal malocclusions using ultrasonography and ultrasonographic elastography and to make interclass assessments. In this study, ultrasonography and ultrasonographic elastography records of 30 Class I individuals (17 females, 13 males), 30 Class II individuals (14 females, 16 males), and 27 Class III individuals (12 females, 15 males) in the normodivergent and growth development periodwere used. The masseter, anterior digastric, and geniohyoid muscles of individualswere examinedusing ultrasonography and ultrasonographic elastography, andcomparisons were madebetween the classes. Statistical analysis was accomplished by Mann Whitney U, One-way ANOVA, Kruskal Wallis H tests. Interclass differences were foundin ultrasonography and elastography measurements of the masseter muscle. However, no differences were observed in ultrasonography measurements of the auxiliary masticatory muscles, whereas differences were seen only in the geniohyoid muscle in elastography measurements among the classes (p<0.05). Individuals with different sagittal skeletal malocclusions during growth and development exhibited similar muscle sizes and elasticities, approximately close to each other.

Hepatic vein Doppler ultrasound to estimate central venous pressure in mechanically ventilated children.

Monitoring central venous pressure (CVP) is crucial for managing critically ill patients yet poses challenges in pediatric cases. This study aimed to correlate CVP with hepatic vein Doppler and IVC ultrasound variables in children. Mechanically ventilated children underwent simultaneous ultrasound and CVP measurements. Hepatic vein Doppler assessed peak velocities (A, S, V, D) and systolic filling fraction. IVC ultrasound included respiratory variability indices, IVC/aorta ratio, and IVC/body surface area ratio. Fifty-three children were included (median age of 8.3months and weight of 6.3kg). Significant correlations were found between CVP values and all hepatic vein Doppler-based variables. The strongest correlation was found between CVP and the sum of the absolute values of the A- and D-wave peak velocities (AD velocity), with a ρ = 0.61 (95% confidence interval [CI] of 0.40 to 0.75; p < 0.001). The AD velocity > 38.55cm/s was able to discriminate patients with CPV > 12mmHg with a sensitivity of 100%, specificity of 95.3%, positive predictive value of 83.3%, and negative predictive value of 100%. No correlations were observed between CVP and variables derived from IVC respiratory variability indices or the IVC/aorta ratio. Conclusion: Hepatic vein Doppler ultrasound provides variables that significantly correlate with CVP and may be useful for estimating cardiac preload in mechanically ventilated children. Indices derived from IVC ultrasound were not reliable for estimating CVP. What is known? • Increased central venous pressure (CVP) can cause interstitial edema and reduce vital organ perfusion, leading to organic dysfunctions, with encapsulated organs such as the kidneys and liver being at higher risk. • However, measuring CVP in children poses challenges due to the difficulties and risks of central venous catheterization, frequent partial or total luminal obstructions in venous catheters, and potential technical errors in measurements. What is new? • Variables obtained through hepatic vein Doppler ultrasonography outperformed those obtained by inferior vena cava ultrasound for estimating CVP in this population. • Hepatic vein Doppler ultrasonography holds potential as an accurate, safe, and non-invasive method for discriminating patients with increased cardiac preload.

Ultrafast Power Doppler Ultrasound Enables Longitudinal Tracking of Vascular Changes that Correlate with Immune Response After Radiotherapy.

While immunotherapy shows great promise in patients with triple negative breast cancer, many will not respond to treatment. Radiotherapy has the potential to prime the tumor-immune microenvironment for immunotherapy. However, predicting response is difficult due to tumor heterogeneity across patients, which necessitates personalized medicine strategies that incorporate tumor tracking into the therapeutic approach. Here, we investigated the use of ultrasound (US) imaging of the tumor vasculature to monitor the tumor response to treatment. We utilized ultrafast power doppler US to track the vascular response to radiotherapy over time. We used 4T1 (metastatic) and 67NR (non-metastatic) breast cancer models to determine if US measurements corroborate conventional immunostaining analysis of the tumor vasculature. To evaluate the effects of radiation, tumor volume and vascular index were calculated using US, and the correlation between vascular changes and immune cell infiltration was determined. US tumor measurements and the quantified vascular response to radiation were confirmed with caliper measurements and immunostaining, respectively, demonstrating a proof-of-principle method for non-invasive vascular monitoring. Additionally, we found significant infiltration of CD8 + T cells into irradiated tumors 10 days after radiation, which followed a sustained decline in vascular index and an increase in splenic CD8 + T cells that was first observed 1 day post-radiation. Our findings reveal that ultrafast power doppler US can evaluate changes in tumor vasculature that are indicative of shifts in the tumor-immune microenvironment. This work may lead to improved patient outcomes through observing and predicting response to therapy.

Evaluation of quadriceps muscle cross-sectional area using an ultrasonic diagnostic equipment with a wide field of view.

Skeletal muscle index measurement via dual-energy X-ray absorptiometry or bioelectrical impedance analysis is used to evaluate muscle mass when diagnosing sarcopenia. However, inherent challenges exist with these methods. We previously focused on muscle mass evaluation in the quadriceps femoris by using computed tomography (CT). In this observational study, we utilized a new ultrasound device with a wide field of view that can obtain CT-like images and investigated its usefulness. Reproducibility was investigated by calculating the intra- and inter-examiner intraclass correlation coefficient (ICC) by using three examiners and performing five measurements in 12 participants. In 123 participants (48 men, 75 women, mean age 78.2 ± 8.1 years), we investigated the correlation between the quadriceps cross-sectional area measured with supine ultrasound and CT images as well as between supine and sitting ultrasound images. Unadjusted, age-adjusted, and age-sex-adjusted correlations were calculated. Reproducibility was excellent (intra-examiner ICC[1,1]: 0.978, 0.987, and 0.994; inter-examiner ICC[2,1]: 0.993). The unadjusted, age-adjusted, and age-sex-adjusted correlations between the quadriceps cross-sectional area measured using supine ultrasound and CT were 0.949, 0.940, and 0.894, respectively. For sitting ultrasound, the corresponding values were 0.958, 0.953, and 0.912, respectively. Correlations between the supine and sitting ultrasound measurements were also good, with corresponding values of 0.952, 0.945, and 0.904, respectively. The tested ultrasound device showed excellent measurement reproducibility and had good correlations with CT images. Further studies with an increased numbers of clinical cases and additional evaluations should allow the device to become a screening tool for diagnosing sarcopenia.

Assessing Clinical Variables Associated With Femoral Muscle Decay as Measured by Point‐of‐Care Ultrasound in Critically Ill Children

ObjectivesSkeletal muscle wasting is a common occurrence in critical illness, often resulting in intensive care unit (ICU)‐acquired weakness. This study aims to identify clinical factors associated with muscle decay in mechanically ventilated critically ill children. Utilizing point‐of‐care ultrasound, a noninvasive and cost‐effective tool, we assess muscle decay through ultrasound of the quadriceps femoris.MethodsA prospective observational study was conducted in a single‐center quaternary‐care pediatric intensive care unit at a children's hospital. A convenience sample of 103 sedated and mechanically ventilated patients were enrolled in this study. Ultrasound measurements of quadriceps femoris muscle thickness were taken, and daily muscle decay rates were calculated. Demographic, clinical, and outcome data were analyzed for correlations with muscle decay.ResultsAmong the enrolled patients, 67 had repeat measurements. Muscle thickness change aligned with prior studies, with a mean daily change of −1.9% [IQR −0.8, −5.0]. Adequate cumulative caloric intake (&gt;60% of goal) correlated with less muscle decay compared with inadequate intake (−1.8 vs −2.4%, P &lt; .001). Average daily muscle change correlated with both ICU and hospital length of stay (LOS) (r = .328, P = .007 and r = .393, P = .001). No significant correlations emerged between muscle change and mortality, disease severity, fluid balance, early mobilization, steroid exposure, or sedative and paralytic use.ConclusionThis study demonstrates early and frequent muscle decay in critically ill children, as detected by point‐of‐care ultrasound. Average daily muscle decay was associated with longer ICU and hospital LOS. Adequate cumulative caloric intake is linked to reduced muscle decay. These findings contribute to understanding muscle wasting in critically ill pediatric patients.

Ultrasound of the spleen - an update on measurements, reference values, and influencing factors. A systematic review.

Reliable and reproducible measurement methods have been established, and reference values are used in almost all scientific disciplines. The knowledge of reference values is crucial to distinguish physiological from pathological processes and, therefore, subsequently, for the clinical management of patients. The image storage and documentation of measurements and normal findings should be part of quality assurance in imaging. This paper aims to review published literature and provide current knowledge of sonographic measurements of the spleen, examination techniques, and knowledge of normal values with their possible clinical implications. Moreover, the role of clinical influencing factors such as age, gender, or ethnicity is also analyzed.

Passive wall thickness monitoring using acoustic emission excitation

Erosion-corrosion is a problematic damage mechanism for the oil and gas industry. To manage the risk of erosion-corrosion networks of particle impact monitoring systems have been installed on pipelines in order to detect acoustic emission from abrasive sand particles impacting the inside surface of the pipe. It would be of value if the existing network of particle impact monitoring systems were not only capable of detecting particle impact, but also sizing the remaining wall thickness. Particle impact monitoring systems are passive and are not generally equipped for excitation. This paper explores the feasibility of using passive acoustic emission transducers for wall thickness measurement, utilizing the fact that active pulse-echo measurements can be approximated by autocorrelating diffuse acoustic waves, such as those generated by particle impact. Two measurement modalities are presented: a) time-of-flight measurements and b) resonant ultrasound spectroscopy measurements. The more usual time-of-flight based measurement is limited by the fact that acoustic emission transducers typically have sensitive bandwidths limited to <1 MHz. The relatively low frequency operation limits the use to thick wall components where the component thickness ≫ ultrasonic wavelength. In thinner walled components a resonant ultrasound spectroscopy approach is required. Experimental measurements are shown that are truly passive (with no purposeful excitation at all), and semi-passive, utilizing acoustic emission from sand impact or compressed air as the excitation source. Results show very good agreement with active measurements.

Lower limb nerve ultrasound: A four-way comparison of acquired and inherited axonopathy, inherited neuronopathy and healthy controls.

In a recent study, we showed that nerve ultrasound of the upper limbs could distinguish inherited sensory neuronopathy from inherited axonopathy; surprisingly, no differences were found in the lower limb nerves. In this study, we compared lower limb nerve ultrasound measurements in inherited neuronopathy, inherited axonopathy, and acquired axonopathy. Tibial and sural nerve ultrasound cross-sectional areas (CSAs) of 34 healthy controls were retrospectively compared with those of three patient groups: 17 with cerebellar ataxia with neuronopathy and vestibular areflexia syndrome (CANVAS), 18 with Charcot-Marie-Tooth type 2 (CMT2), and 18 with acquired length-dependent sensorimotor axonal neuropathy, using ANOVA with post-hoc Tukey honestly significance difference (HSD) (significance level set at p < .05). The nerve CSAs of CANVAS and CMT2 patients were not significantly different. Both the tibial and the sural nerve CSAs were significantly smaller in CANVAS and CMT2 compared with the acquired axonal neuropathy group. Tibial nerve CSAs of CANVAS and CMT2 were significantly smaller than controls. Tibial and sural nerve CSAs of the acquired axonal neuropathy group were also significantly larger than the controls'. Ultrasound of the lower limb nerves distinguished inherited from acquired axonopathy with the nerve size respectively reduced and increased in these two groups. This has potential implication for the differential diagnosis of these diseases in clinical practice.

Comparison of ultrasound assisted and intraoperative diameter measurement in acute appendicitis.

Detailed anamnesis and systematic physical examination are often relevant in the diagnostic routine of acute appendicitis. However, physicians are increasingly motivated to obtain radiological approval. Inherent limitations due to radiologists' experience and the presenting anatomy may result in contradictory outcomes between the described and intraoperative findings. In this study, a comparison of anthropometric measurements of the appendix vermiformis obtained by radiologists and surgeons in children with acute appendicitis is discussed. The external appendiceal diameter in 53 patients who underwent surgery between April 2022 and January 2024 was measured at three different anatomical locations during preoperative ultrasound and intraoperatively with the help of Vernier calipers. Appendectomy materials were classified into negative, acute, and complicated appendicitis subgroups on the basis of histopathological results. The widest median diameter, expressed in millimeters, was analyzed statistically in terms of diagnostic accuracy. Histopathological analysis revealed negative appendectomy in 15.1%, acute appendicitis in 66%, and complicated appendicitis in 18.8% of the patients. The median age at presentation was 11.4 years (4-17.3 years), and 45.3% of the patients were females. The average median appendiceal diameter was 7.8 ± 2.4 mm according to the caliper and 7.9 ± 2.7 mm according to ultrasound (p > 0.05). The evaluation by the caliper revealed a much smaller diameter in 19 patients than did ultrasound. The appendiceal diameter of eight documented negative appendectomy samples was 7 mm or greater. US failed to identify the presence of an appendicolith in 11 cases (20.8%), all of which were disclosed during histopathological evaluation. It is possible to conclude that ultrasound and intraoperative anthropometric measurements correlate according to our study. Diagnostic accuracy, however, which is individually based on ultrasound appendix diameter values greater than 6 mm, is controversial. It is clear that comparison and further reinterpretation of such anthropometric measurements in light of histopathological consequences may help diminish the frequency of negative and perforated appendectomies.

Intrarater and Interrater Reliability of Quantitative Ultrasound Speed of Sound by Trained Raters at the Distal Radius in Postmenopausal Women.

Quantitative ultrasound (QUS) performed at the distal radius shows potential as an effective tool for evaluating fracture risk, especially in postmenopausal women, but the reliability of this tool has not been reported in this patient population. This study investigated the within-day intrarater and interrater reliability of trained raters performing QUS measures at the distal radius of postmenopausal community-dwelling women. Eighteen women between the ages of 56 and 87years were recruited from senior centers in the Greenville area of South Carolina and consented to participate. A QUS bone sonometer was used in this study; the trained raters performed 3 repeated speed of sound (SOS) measures at the nondominant radius of each participant on the same day. Intraclass correlation coefficients (ICCs) were calculated (model 3,1 for intrarater and 2,3 for interrater reliability) to determine the reliability within and between raters. In addition, we calculated the standard error of measurement (SEM) and the minimal detectable change at 95% confidence interval (MDC 95 ). The within-day intrarater reliability was excellent for both physical therapist raters (ICC (3,1) ranging from 0.93 to 0.91). The SEM and MDC for the within-day intrarater reliability measures were small for both raters (SEM=36.79-38.75 or 0.92%-0.97% of the pooled mean; MDC 95 =101.99-107.40). The interrater reliability for SOS measurements using radial QUS was good with an ICC (2,3) of 0.77 (95% CI, 0.36-0.92) for 3 averaged measures. The SEM and MDC were larger for the interrater reliability measures (SEM=62.79 or 1.57% of the pooled mean; MDC 95 =174.05). Quantitative ultrasound SOS measurement at the distal radius showed excellent within-day intrarater and good interrater (when 3 measures were averaged) reliability in community-dwelling postmenopausal women. The SEM and MDC 95 were also low for interrater reliability when a mean of 3 trials was used. This study is the first to demonstrate that this particular QUS device at the radius may be a reliable fracture risk screening tool for postmenopausal women.

The LUSBI Protocol (Lung Ultrasound/BREST Score/Inferior Vena Cava)-Its Role in a Differential Diagnostic Approach to Dyspnea of Cardiogenic and Non-Cardiogenic Origin.

Background and Objectives: PoCUS ultrasound applications are widely used in everyday work, especially in the field of emergency medicine. The main goal of this research was to create a diagnostic and therapeutic protocol that will integrate ultrasound examination of the lungs, ultrasound measurements of the inferior vena cava (assessment of central venous pressure) and BREST scores (risk stratification for heart failure), with the aim of establishing a more effective differential diagnostic approach for dyspneic patients. Materials and Methods: A cross-sectional study was conducted in the emergency medicine department with the educational center of the community health center of Banja Luka. Eighty patients of both sexes were included and divided into experimental and control groups based on the presence or absence of dyspnea as a dominant subjective complaint. Based on the abovementioned variables, the LUSBI protocol (lung ultrasound/BREST score/inferior vena cava) was created, including profiles to determine the nature of the origin of complaints. The biochemical marker of heart failure NT pro-BNP served as a laboratory confirmation of the cardiac origin of the complaints. Results: The distribution of NT pro BNP values in the experimental group showed statistically significant differences between individual profiles of the LUSBI protocol (p < 0.001). Patients assigned to group B PLAPS 2 had significantly higher average values of NT pro-BNP (20159.00 ± 3114.02 pg/mL) compared to other LUSBI profiles. Patients from the experimental group who had a high risk of heart failure according to their BREST scores also had a significantly higher average maximum expiratory diameter compared to those without heart failure (p = 0.004). A statistically significant difference (p = 0.001) in LUSBI profiles was observed between the groups of patients divided according to CVP categories. Conclusion: The integration of the LUSBI protocol into the differential diagnosis of dyspnea has been shown to be very effective in confirming or excluding a cardiac cause of the disease in patients.