Difference In Shear Wave Velocity Research Articles

Evaluating Skin Involvement in Systemic Sclerosis Using High-Frequency Ultrasound and Virtual Touch Tissue Imaging

ObjectiveThis study aimed to explore the diagnostic significance of high-frequency ultrasound combined with visual touch tissue imaging quantification (VTIQ) in the diagnosis and management of systemic sclerosis (SSc). MethodsPatients diagnosed with SSc and normal volunteers were recruited and divided into an experimental group and a control group, with 30 cases in each group, respectively. The skin thickness at six sites was assessed using high-frequency ultrasound, and the shear wave velocity (SWV) was determined using the VTIQ method. The differences in skin thickness and SWV between the experimental group and the control group were compared and a receiver operating characteristic (ROC) curve was plotted. The value of high-frequency ultrasound, VTIQ, and high-frequency ultrasound combined with VTIQ for evaluating skin involvement in SSc was determined. ResultsThe difference in SWV sum at six sites and the thickness sum was statistically significant (all p = 0.000 < 0.05) from that of the control group, and there was a strong association between the SWV sum, thickness sum, and Rodnan skin score at the six sites in the experimental group (p = 0.000, r = 0.726; p = 0.000, r = 0.679). Based on the ROC curve, the area under the curve (AUC) for high-frequency ultrasound examination was 0.789. The AUC for VTIQ examination was 0.893, while the AUC for high-frequency ultrasound combined with VTIQ examination was 0.923. The combined examination method showed the highest AUC, indicating the best diagnostic performance. ConclusionThe integration of high-frequency ultrasound and VTIQ provides a quantitative approach for assessing the extent of skin involvement in SSc patients, offering valuable insights for clinical diagnosis and treatment purposes.

Clinical Applicability of Ultrasound Shear Wave Elastography in Patients under Hypoglossal Nerve Stimulation Therapy

Relationship between stiffness of genioglossi (GG) and geniohyoidei (GH) muscles under electric hypoglossal nerve stimulation therapy (HNS) in relation to success of therapy was investigated with additional special focus on tongue movement. Patients and Methods: Clinical and sleep laboratory parameters of a cohort of 18 patients with known shear wave velocity (SWV) data of the ipsilateral and contralateral musculi GG and GH (sGG, sGH and nGG, nGH) before and under HNS therapy were analyzed. The SWV was already determined using the ultrasonic shear wave elastography (US-SWE) technique. Results: Median Epworth Sleepiness Scale (ESS) was 8 (IQR 12), median baseline Apnoe–Hypopnoe Index (AHI) 31.65 (IQR 25.1), median AHI under HNS therapy 16.3 (IQR 20.03). Therapy success: 9/18 patients (AHI during therapy &lt; 15/h). There was no significant difference in SWV (sGG, sGH, nGG and nGH) between therapy responders and non-responders during therapy. Also, no difference could be seen with respect to the difference and increase in SWV values without and with stimulation. Examination of SWV values (sGG, sGH, nGG, nGH during stimulation, difference of SWV values stimulation − no stimulation, increase factor of SWV) revealed a significant negative correlation between the AHI under therapy and the measured SWV of the musculus GH of the contralateral side during stimulation (−0.622, p = 0.006). Patients with bilateral protrusion of the tongue differed regarding to therapy success in increase in SWV in sGG (p = 0.032). Tongue protrusion to contralateral: A significant difference between patients with AHI during therapy &lt; 15/h in SWV values at sGG without stimulation (p = 0.021) was seen, with also a correlation to the current AHI under therapy (p = 0.047) and the change factor of the AHI (p = 0.015). Conclusion: Stiffness of the target muscle does not appear to be an isolated measure of the success of HNS therapy. This observation may have implications for future decision-making processes in the process of titrating electrical therapy parameters. But the technique of US-SWE may be useful for future research of the neurophysiology of the tongue and OSA phenotyping.

Spinal stiffness assessment by shear wave imaging in a genetic zebrafish scoliosis model treated with anti-inflammatory medication

Background: Idiopathic scoliosis (IS) is a disease characterized by an abnormal lateral curvature of the spine that affects up to 4% of the population. Recent models in zebrafish have elucidated genetic variants which contribute to scoliotic curvature through mechanisms of neuroinflammation, and oxidative stress. Additionally, in-vivo clinical studies have demonstrated that spinal structures stiffen in patients with IS. Shear wave elastography (SWE) is novel, non-invasive imaging technique used to quantitatively estimate tissue stiffness. Objective: Here, we investigated spinal stiffness using SWE in genetically mutant zebrafish with a heterozygous scoliosis variant ( dmh4/+) treated with N-acetylcysteine ethyl ester (NACET), a potent anti-oxidant and anti-inflammatory medication which has been demonstrated to reduce scoliosis curvature formation in zebrafish by up to 70%. Hypothesis: Compared to wildtype, spinal stiffness will increase in dmh4/+ zebrafish and there will be no difference in stiffness for NACET treated zebrafish. Methods: Wildtype (WT; n=20) and mutant ( dmh4/+; n=20) zebrafish aged 10 days post fertilization (dpf) (n=10 &amp; n=10 treated with 500 μM of NACET), 16 dpf (n=10), and 21 dpf (n=10) were sacrificed and submerged in a dish containing 2% low melt agarose gel. An 18.75 MHz linear ultrasound probe was clamped to the dish apparatus dorsal to the zebra fish. Spinal stiffness was assessed by SWE, where faster shear wave velocities (SWV) represent stiffer tissue. The SWV data was processed using a well-verified, custom SWE analysis program on MATLAB by a n operator blinded to the zebrafish genotypes. Results: The spinal curvature of dmh4/+ zebrafish aged 10 dpf were morphologically indistinguishable from WT zebrafish aged 10 dpf. SWV was significantly increased in dmh4/+ zebrafish aged 10 dpf compared to WT (p&lt;0.05). There was no difference in SWV between NACET treated dmh4/+ and NACET treated WT zebrafish aged 10 dpf (p&gt;0.05). Furthermore, NACET treated dmh4/+ and WT zebrafish aged 10 dpf exhibited no difference in SWV compared to untreated WT zebrafish aged 10 dpf (p&gt;0.05). Additionally, SWV was significantly increased in dmh4/+ zebrafish aged 16 and 21 dpf compared to WT (p&lt;0.05). Conclusion: Here we demonstrate that spinal stiffness increases in zebrafish with scoliosis before the curvature pheno type is present and this increase in stiffness is sustained throughout development in later ages. Additionally, spinal stiffness in scoliosis is reduced following treatment with NACET. Our results provide evidence to support clinical trials assessing stiffness as preclinical diagnostic criteria for IS in children. Biotalent Canada - public grant This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effectiveness of 2‐dimensional shear wave elastography for noninvasive and reliable estimation of right atrial pressure in dogs with induced volume overload

Two-dimensional shear wave elastography (2D-SWE) provides information on hepatic elastic modulus as shear wave velocity (SWV). To assess SWV using 2D-SWE in dogs with induced volume overload, investigate the relationship between this information and right atrial pressure (RAP) measured by invasive right heart catheterization, and also evaluate the difference in SWV before and after diuretic administration. Six healthy beagles. Prospective experimental study. Right heart catheterization and 2D-SWE were performed in 6 anesthetized beagles at baseline and after the induction of volume overload. Volume overload was induced by IV hydroxyethyl starch 70/0.5 infusion (100 mL/kg/h). Furosemide (4-6 mg/kg, IV) was administered, and the SWVs were measured. Shear wave velocity showed a significant gradual increase during acute volume overload compared to baseline. SWV was significantly positively correlated with RAP (P < .0001, ρ = 0.9729). The area under the curve of SWV to predict RAP at >10, >15, and >20 mm Hg was 0.9896 (95% confidence interval [95% CI], 0.9690-1.000), 0.9907 (95% CI, 0.9701-1.000), and 0.9722 (95% CI, 0.9280-1.000), respectively. The SWV after diuretic use decreased significantly. Two-dimensional shear wave elastography might be useful for noninvasive and reliable estimation of RAP in dogs with acute volume overload and has potential as a quantitative biomarker for evaluating therapeutic response in dogs with right sided congestive heart failure.

Shear wave elastography evaluation of cats with chronic kidney disease.

Chronic kidney disease (CKD) is a major health condition in cats that can lead to poor quality of life and financial implications for therapy. Currently staging and identification of CKD is limited by diagnostic testing such as creatinine and urine-specific gravity, which do not change until late in the disease course. Other methods to evaluate CKD would be valuable in the clinical setting. Shear wave elastography is one novel ultrasound method, which has shown promise in identifying increases in tissue stiffness and identifying CKD in people. As CKD is often histologically characterized by tubulointerstitial fibrosis, shear wave elastography has the potential to identify CKD and differentiate between stages of CKD in cats. This prospective observational case-control study with 78 cats found no difference in shear wave velocities between groups (P=0.33), a contradictory finding to one prior publication. There was no effect of weight (P=0.65), nor the presence of mineralization (P=0.31) or infarction (P=0.52) on cortical shear wave velocities. There was a significant effect of age on shear wave velocity (P=0.018) where velocities increased with age. The intraclass correlation coefficient was only moderate (0.62). Possible reasons for the difference in results between our work and that published prior, include differences in methodology and differences in instrumentation. Variability in measurements in our population may be due to the effects of respiratory motion or limitations in shear wave elastography software. As such, shear wave elastography is not currently recommended as a tool to evaluate CKD in cats and further work is necessary.

A Comparison of Shear Wave Elastography between Normal Myometrium, Uterine Fibroids, and Adenomyosis: A Cross-Sectional Study.

BackgroundThe differential diagnosis between uterine fibroid and adenomyosis is sometimes difficult; a precise diagnosis is required in women with infertility because of the different choice of treatments. Ultrasound elastography (UE) is a novel technique to evaluate the elasticity or the stiffness of the tissue of interest. The present study aims to compare UE shear wave velocity (SWV) among normal uterine myometrium, uterine fibroid, and adenomyosis, and assess the accuracy of shear wave elastography in the diagnosis of adenomyosis.Materials and MethodsThis cross-sectional study recruited 25 subjects for each group (control, adenomyosis, and fibroid) from April 2019 to April 2020. Transvaginal UE using an Aplio 500 (Toshiba Medical Systems, Japan) with ultrasound mapping for point of tissue biopsy was performed for all subjects. The diagnosis was confirmed by histology. Masson’s trichrome staining for collagen was performed and quantifiedResultsThe mean ± standard deviation (SD) for SWV was 3.44 ± 0.95 m/seconds (control group), 4.63 ± 1.45 m/seconds (adenomyosis group), and 4.53 ± 1.07 m/seconds (fibroid group). The mean SWV differed when comparing normal myometrium and adenomyosis after adjustments for age and endometrial pathology (P=0.019). The cut-off point of SWV at 3.465 m/seconds could differentiate adenomyosis from the normal uterus with an 80% sensitivity, 80% specificity, and an area under the curve (AUC) of 0.80 (95% confidence interval [CI]: 0.68-0.93) (P<0.001). No significant difference in SWV between the adenomyosis and fibroid groups was detected.ConclusionShear wave elastography could be an alternative tool to distinguish between normal myometrium and adenomyosis; however, it could not differentiate adenomyosis from uterine fibroid or uterine fibroid from normal myometrium.

Ultrasound Shear Wave Elastography of the Tongue during Selective Hypoglossal Nerve Stimulation in Patients with Obstructive Sleep Apnea Syndrome

Currently, there is no established technique to directly measure extrinsic tongue muscle activation during selective hypoglossal stimulation therapy (sHNS) in patients with obstructive sleep apnea syndrome (OSAS) in a simple, non-invasive clinical setting. Ultrasound shear-wave elastography (US-SWE) enables quantitative measurement of tissue stiffness. We investigated whether US-SWE is able to detect changes in muscle stiffness of the tongue during sHNS. Patients with OSAS treated with sHNS were prospectively enrolled. A standardized US-SWE protocol was used to selectively measure tissue stiffness of the geniohyoid muscle (GH) and genioglossus (GG) muscles on the side of stimulator implantation (sGH, sGG) and on the contralateral side (nGH, nGG) without and with sHNS. Eighteen patients were included (median age = 62 years, interquartile range: 56–65, 83.3% male). Median shear-wave velocity (SWV) increased during contraction with each patient's clinically prescribed therapeutic regimen in the sGH (+19%, p = 0.020) and sGG (+81%, p < 0.001) and decreased during contraction in the nGH (–8%, p = 0.107) and nGG (–8%, p = 0.396). Differences in SWV during contraction were significant only on the side of stimulation (sGG +81%, sGH +19%). SWE measurements had excellent reliability as reflected by a Cronbach α value ≥0.9 for all target muscles pre- and post-contraction and an item–total correlation ≥0.5. US-SWE allows reliable measurement of SWV as an indicator of muscle stiffness of extrinsic tongue muscles. This non-invasive method provides new possibilities to distinguish and characterize responders from non-responders in hypoglossal stimulation therapy. Compared with the regular visual assessment of tongue movement, US-SWE of individual muscle groups provides a new non-invasive imaging tool in patients with OSAS.

Noninvasive, objective evaluation of lower extremity lymphedema severity using shear wave elastography: A preliminary study

Increased skin and subcutaneous tissue stiffness in patients with early-stage lymphedema has been reported. The purpose of this study was to examine the use of shear wave elastography (SWE) for evaluating lower extremity lymphedema (LEL). For 10 lower extremities of normal controls and 72 limbs of patients with gynecological cancer whose lymphatic function was categorized into six stages based on the range of dermal backflow (DBF) observed in indocyanine green (ICG) lymphography, SWE was performed and shear wave velocity (SWV) of the dermis and three layers of subcutaneous tissue at the thigh and calf were recorded. Twenty-five patients underwent thigh tissue histological and dermal thickness examinations. The strongest correlation between the ICG DBF stage and SWV during SWE was observed on the dermal layer of the thigh (p < 0.01, R=0.67). There was a significant correlation between the dermal thickness of the thigh and the ICG DBF stage (p < 0.01, R=0.87) and also between the dermal thickness of the thigh and SWV (p < 0.01, R=0.73). Noninvasive, objective evaluation of LEL severity using SWE was well correlated with lymphatic function as determined by ICG lymphography. The DBF changes in the dermis of the thigh best reflected the changes in lymphatic function. Dermal thickness variations may partially account for differences in SWV.

Preliminary study on the influencing factors of shear wave elastography for peripheral nerves in healthy population

This study took shear wave elastography (SWE) technology to measure the shear wave velocity (SWV) of peripheral nerve in healthy population, which represents the stiffness of the peripheral nerves, and research whether these parameters (location, age, sex, body mass index (BMI), the thickness and cross-sectional area(CSA) of the nerve) would affect the stiffness of the peripheral nerves. 105 healthy volunteers were enrolled in this study. We recorded the genders and ages of these volunteers, measured height and weight, calculated BMI, measured nerve thickness and CSA using high-frequency ultrasound (HFUS), and then, we measured and compared the SWV of the right median nerve at the middle of the forearm and at the proximal entrance of the carpal tunnel. The SWV of the median nerve of the left side was measured to explore whether there exist differences of SWV in bilateral median nerve. Additionally, we also measured the SWV of the right tibial nerve at the ankle canal to test whether there is any difference in shear wave velocity between different peripheral nerves. This study found that there existed significant differences of SWV between different sites in one nerve and between different peripheral nerves. No significant difference was found in SWV between bilateral median nerves. Additionally, the SWV of peripheral nerves was associated with gender, while not associated with age or BMI. The mean SWV of the studied male volunteers in median nerve were significantly higher than those of female (p < 0.05). Peripheral nerve SWE measurement in healthy people is affected by different sites, different nerves and genders, and not associated with age, BMI, nerve thickness or CSA.

Local myocardial stiffness variations identified by high frame rate shear wave echocardiography

BackgroundShear waves are generated by the closure of the heart valves. Significant differences in shear wave velocity have been found recently between normal myocardium and disease models of diffusely increased muscle stiffness. In this study we correlate in vivo myocardial shear wave imaging (SWI) with presence of scarred tissue, as model for local increase of stiffness. Stiffness variation is hypothesized to appear as velocity variation.MethodsTen healthy volunteers (group 1), 10 hypertrophic cardiomyopathy (HCM) patients without any cardiac intervention (group 2), and 10 HCM patients with prior septal reduction therapy (group 3) underwent high frame rate tissue Doppler echocardiography. The SW in the interventricular septum after aortic valve closure was mapped along two M-mode lines, in the inner and outer layer.ResultsWe compared SWI to 3D echocardiography and strain imaging. In groups 1 and 2, no change in velocity was detected. In group 3, 8/10 patients showed a variation in SW velocity. All three patients having transmural scar showed a simultaneous velocity variation in both layers. Out of six patients with endocardial scar, five showed variations in the inner layer.ConclusionLocal variations in stiffness, with myocardial remodeling post septal reduction therapy as model, can be detected by a local variation in the propagation velocity of naturally occurring shear waves.

Evaluation of the possibilities of shear wave elastography for differentiation of lymphomatous and reactive changes of superficial lymph nodes

Objective: to evaluate the possibilities of ultrasound elastography for differentiation of reactive and lymphomatous superficial lymph nodes (LN).Materials and methods. The prospective study included 138 patients with enlarged superficial LN. Based on a previous histological examination, patients were divided into two groups: 1st group (n = 108) – patients with non-Hodgkin’s lymphomas and Hodgkin’s lymphoma; 2nd (n = 30) – patients with reactive (inflammatory) changes in superficial LN. All patients underwent ultrasound elastography of the enlarged LN using ARFI technology.Results. According to the results of ultrasound elastography, the average, minimum, and maximum shear wave velocities for enlarged LN in lymphoma (1st group) were 2.616 ± 0.684; 1.980 ± 0.557 and 3.351 ± 0.987 m / s, respectively; for LN with reactive changes (2nd group) – 1.704 ± 0.223; 1.414 ± 0.209 and 2.027 ± 0.261 m / s, respectively. Thus, the average, minimum, and maximum values of shear wave velocities significantly different between the groups (p ˂0.001). The cut off values of the average shear wave velocity in the differential diagnosis of lymphoma and hyperplasia are determined at the level of 2.05 m / s, with a sensitivity of 88.5 %, specificity of 100 %, and AUC of 0.942 (p ˂0.001).Conclusion. Ultrasound elastography demonstrated statistically significant differences in shear wave velocity in the enlarged superficial LN in lymphoma and in inflammatory processes that can be used as a preliminary non-invasive differential diagnosis of enlarged superficial LN in these conditions.

Acoustic radiation force impulse imaging of pancreas in patients with early onset idiopathic recurrent acute pancreatitis.

Patients with recurrent acute pancreatitis (RAP) may progress to chronic pancreatitis (CP). A critical step in this progression is the development of fibrosis. Elastography has been used to assess degree of fibrosis by measurement of shear wave velocity (SWV). The aim of this study was to measure the stiffness of pancreas as a surrogate for pancreatic fibrosis in patients with RAP and compare it with a group of individuals without any history of pancreatic disorders. Using acoustic radiation force impulse (ARFI) imaging SWV was calculated in 31 patients with idiopathic RAP having disease onset ≤30 years. A control group of 31 individuals with no history pancreatic disorder and no features of CP on endosonography was selected for comparison. ARFI imaging was done by a single radiologist who was blinded to the cases and controls RESULTS:: Mean age of patients with RAP was 24.8 (SD 9.86) years, disease duration was 3.45 (interquartile range 1-5) years, mean number of episodes 4.9 (SD 2.72). There was a significant difference in SWV between patients (1.27 ± 0.50 m/s) and controls (1.00 ± 0.17 m/s) (P = 0.001)). There was a positive correlation between SWV and number of pain episodes (P = 0.026) and negative correlation with BMI (P = 0.002). SWV was high in patients with RAP indicating a stiff pancreas. The stiffness increases with the number of episodes of pancreatitis.

Estimating Near-Surface Shear-Wave-Velocity Structures Via Multichannel Analysis of Rayleigh and Love Waves: An Experiment at the Boise Hydrogeophysical Research Site

Surface-wave analysis has been widely used for near-surface geophysical and geotechnical studies by using the dispersive characteristic of surface waves (Rayleigh or Love waves) to determine subsurface model parameters. Unlike Rayleigh waves, the dispersive nature of Love waves is independent of P-wave velocity in 1D models, which makes Love-wave dispersion curve interpretation simpler than Rayleigh waves. This reduces the degree of nonuniqueness leading to more stable inversion of Love-wave dispersion curves. To estimate the near-surface shear-wave velocities (Vs) using multichannel analysis of Rayleigh (MASW) and Love waves (MALW) for hydrologic characterization, we conducted an experiment at the Boise Hydrogeophysical Research Site (BHRS, an experimental well field located near Boise, Idaho, USA). We constructed the pseudo-3D velocity structures at the BHRS using both the MASW and MALW methods and compared the results to borehole measurements. We used the 3D Vs distribution to identify and resolve the extent of a relatively low-velocity anomaly caused by a sand channel. The Vs structure and anomaly boundaries were delineated at the meter scale and confirmed by the ground-penetrating radar surveys. The differences in shear-wave velocity determined by MASW, MALW and borehole measurements were discussed and interpreted to reflect the near-surface anisotropy associated with the hydrologic characteristics at the BHRS. Our results demonstrated that the combination of MALW and MASW can be a powerful tool for near-surface characterization.

Relationships between cardiovascular disease risk factors and Achilles tendon structural and mechanical properties in people with Type 2 Diabetes

Background. Patients with diabetes have 44% greater risk of tendon rupture requiring hospitalisation. Despite this, in vivo research of the associations of diabetes and other cardiovascular disease risk factors on structural and mechanical properties of the Achilles tendon are sparsely studied.Methods. Inactive individuals with type 2 diabetes (n=33) underwent ultrasound and shear wave elastography imaging of their Achilles tendons bilaterally to measure thickness and shear wave velocity (SWV), an index of tendon elastic modulus. In a separate session, participants underwent assessment of body composition, cardiorespiratory fitness and blood biomarkers. Seven inactive individuals without type 2 diabetes were recruited for comparison of tendon structural and mechanical properties.Results. In participants with diabetes, free tendon SWV displayed large negative correlations with hip circumference (r=-0.67, P <0.001), waist circumference (r=-0.59, P <0.001) and body mass index (r=-0.52, P <0001), and a moderate positive correlation with VO2 peak (r=0.34, P =0.006). SWV was lower in participants with diabetes taking statins compared to not taking statins (Free tendon: median difference 8%, P=0.004); insertion: 11%, P =0.001). Compared to the control group, the diabetes group had thicker Achilles free tendon (median difference 15%, P<0.001) and Achilles insertion (17%, P=0.006), but no differences in SWV (P=0.490 or 0.577 respectively).Conclusions. Achilles tendons from individuals with type 2 diabetes were thicker compared to inactive individuals without diabetes. Adiposity, statin use and low cardiorespiratory fitness were associated with inferior Achilles tendon mechanical properties in people with diabetes.

Muscle stiffness in rheumatoid arthritis is not altered or associated with muscle weakness: A shear wave elastography study

Objectives: To investigate muscle stiffness and strength in rheumatoid arthritis patients compared to healthy controls.Methods: A sample of 80 RA patients from three discrete groups: 1 – newly diagnosed treatment-naïve RA (n = 29), 2 – active RA for at least 1 year (n = 18) and 3 – in remission RA for at least 1 year (n = 33), was compared to 40 healthy controls. Shear wave velocity (SWV) was measured using shear wave elastography as a surrogate for tissue stiffness in multiple muscles. All participants performed isometric grip strength, timed get-up-and-go test, 30-s chair stand test and isokinetic knee extension/flexion (60°/s). The difference in SWV amongst the groups was tested using one-way ANOVA, and the correlation between SWV and muscle strength results were calculated using Pearson’s coefficients.Results: The mean age ± SD was 61.2 ± 12.8 for RA patients and 61.5 ± 10.5 years for controls. SWV was not significantly different amongst the groups on all muscles (p > .05). In comparison to controls, the new and active RA groups showed a significantly lower isokinetic strength by –29% (p = .013) and –28% (p = .040), fewer chair stands by –28% (p = .001) and –44% (p < .001), longer walking times by –25% (p = .025) and –30% (p = .001), respectively, and weaker grip strength by –45% for both (p < .001). The muscle strength in the remission RA groups was not significantly lower, except in the isokinetic knee strength (–21%; p = .027). The correlations between SWE and the muscle assessment results were weak and insignificant (r < 0.30; p > .05).Conclusion: Significant muscle weakness was demonstrated in patients with RA disease. However, muscle stiffness was normal and not associated with muscle strength.

Fully automated dynamic ultrasound skeletal muscle analysis during walking exercise

The plantar fascia is exposed to repetitive tensile stress induced by cyclic loads associated with daily activities, such as walking and running. Due to overuse or abnormal foot alignment, insertional and distal (i.e., mid-substance) regions within the plantar fascia may exhibit microtears, which leads to plantar fasciopathy. Ultrasound shear wave elastography is an imaging technique to measure shear wave velocity propagating through biological tissues, considered herein as an index of tensile stress. This study aimed to quantify the effect of toe dorsiflexion on the regional distribution of plantar fascia shear wave velocity.Shear wave velocity of the plantar fascia was measured in the insertional and distal regions using ultrasound shear wave elastography in sixteen healthy participants (7 males and 9 females). The measurements were performed while the toes were maintained in neutral or dorsiflexed positions.When considering the insertional region, there was no significant difference in shear wave velocity between neutral toe position [mean (SEM): 5.4 (0.6) m/s] and dorsiflexed toe position [5.5 (0.5) m/s] (P = 0.88; effect size = 0.05). When considering the distal region, there was a significant difference in shear wave velocity between the neutral position [7.8 (0.4) m/s] and dorsiflexed position [9.9 (0.3) m/s] (P = 0.002; effect size = 0.88). The difference in shear wave velocity between the insertional and distal regions showed a large effect size for either neutral (P = 0.010; effect size = 0.75) or dorsiflexed toe position (P = 0.003; effect size = 0.86).In contrast to clinical beliefs, these findings suggest that toe dorsiflexion induces non-homogeneous changes in tensile stress within the plantar fascia.

Ultrasound Shear Wave Elastography to Assess Osteopathic Manipulative Treatment on the Iliocostalis Lumborum Muscle: A Feasibility Study.

To investigate the feasibility of ultrasound shear wave elastography (SWE) in assessing iliocostalis lumborum muscle changes after osteopathic manipulative treatment (OMT). Using a linear array ultrasound transducer (4-9 MHz), we prospectively measured the shear wave velocity (SWV) of bilateral iliocostalis lumborum muscles in 20 patients with low back somatic dysfunction and in 9 age-matched healthy volunteers. The SWV was measured in muscle relaxation and contraction in all participants and immediately before and after OMT in patients. We developed a muscle SWV rate [SWVcontraction - SWVrelaxation )/SWVrelaxation ] and an SWV improvement index [(SWVpre-OMT - SWVpost-OMT )/SWVpre-OMT ] for quantifying muscle contractibility and changes in muscle stiffness after OMT. Statistical analyses included an unpaired t test to analyze the difference in the muscle SWV between muscle relaxation and contraction and between somatic dysfunction and nonsomatic dysfunction in patients and healthy volunteers, a paired t test to examine the difference in the SWV and SWV rate before and after OMT, the intraclass correlation coefficient to test intraobserver and interobserver reliability, and Spearman rank correlation to analyze the correlation of changes in the SWV with manual osteopathic assessments. The mean ages of the patients with low back somatic dysfunction and the healthy volunteers were 28 and 26 years, respectively. The muscle SWV significantly differed between somatic dysfunction and nonsomatic dysfunction in patients and healthy volunteers, between muscle relaxation and contraction, and before and after OMT (P < .001). The SWV improvement index moderately correlated with manual osteopathic assessments (r = 0.68). The interobserver and intraobserver reliability for performing SWE was good (intraclass correlation coefficient, >0.8). Our results suggest that SWE is feasible for quantifying the change in muscle stiffness and contractibility after OMT.

Ultrasound shear wave elastography in assessment of skeletal muscle stiffness in senior volunteers

Purpose: The aim of the study was to evaluate the reliability of ultrasound shear wave elastography (SWE) to assess biceps brachii muscle (BBM) and quadriceps muscle (QM) stiffness in senior volunteers.Methods: Using a linear array ultrasound transducer (7 MHz), we prospectively measured shear wave velocity (SWV) of BBM and QM in passive joints (elbow and knee) flexion (90°) and extension (180°) in 19 senior volunteers by two operators. We developed SWV rate (SWVelbow-extension – SWVelbow-flexion)/SWVelbow-flexion to assess BBM contractibility. Statistical analysis included unpaired t-test to examine the difference in SWV of muscle between left vs right limbs, men vs women, and athletes vs nonathletes; Intraclass correlation coefficient (ICC) and violin plots for analyzing intra- and inter-observer reliability in performing SWE in muscles.Results: There was no significant difference in SWV between left vs right (flexion or extension), male vs female (flexion or extension), for BBM and QM, and athlete vs nonathlete extension for QM (all p > 0.05). The difference in SWV of BBM in elbow extension and in SWV rate between athlete and nonathlete was significant (p < 0.05). The difference in muscle SWV between joint flexion and extension was also significant (p < 0.05). Reliability in performing SWE of BBM and QM was good (ICC > 0.75).Conclusions: Our results suggest that ultrasound SWE is feasible in estimating BBM and QM stiffness in seniors with good reproducibility. SWV rate and SWV of the extended BBM representing muscle contractibility in athlete were higher than in nonathlete.

Patchy echogenicity of the liver in patients with chronic hepatitis B does not indicate poorer elasticity.

PurposeThis study was conducted to investigate whether the presence of patchy echogenicity in the liver of patients with chronic hepatitis B (CHB) is predictive of liver stiffness.MethodsA total of 200 CHB patients with and without patchy echogenicity of the liver were assigned to two groups, with 100 patients in each group, and 32 of them underwent liver biopsy. Additionally, 80 healthy subjects, 100 inactive HBV carriers, and 100 patients with decompensated hepatic cirrhosis were assigned to the control groups. Laboratory tests and clinical data were collected, and shear wave velocity (SWV) of the liver was measured for all 480 subjects.ResultsThe median SWV in patients with a normal liver, inactive hepatitis B virus carriers, CHB patients with and without patchy echogenicity, and decompensated hepatic cirrhosis were 1.07 m/sec, 1.08 m/sec, 1.16 m/sec, 1.16 m/sec, and 2.02 m/sec, respectively; there was no significant difference in SWV values between CHB patients with patchy echogenicity and those without patchy echogenicity. Furthermore, among CHB patients with and without patchy echogenicity, no significant difference in SWV was found according to fibrosis stage.ConclusionThe presence of patchy echogenicity of the liver does not indicate a higher degree of liver stiffness.

Muscle material properties in passive and active stroke-impaired muscle

Stroke survivors routinely experience long-term motor and sensory impairments. In parallel with neurological changes, material properties of muscles in the impaired limbs, such as muscle stiffness, may also change progressively. However, these stiffness measures are routinely derived from individual joint stiffness, representing whole muscle groups. Here, we use shear wave (SW) ultrasound elastography to measure SW velocity, as a surrogate measure of stiffness, to quantify material properties in individual muscles. Accordingly, the purpose of this study was to compare muscle material properties of the bicep brachii in stroke survivors and in age-matched control subjects by measuring SW velocity at rest and different voluntary activation levels. Our main findings show that at rest, the SW velocity was on average 41% greater in the paretic muscle compared the contralateral non-paretic muscle. The mean passive SW velocity across all subjects were 2.34 ± 0.41 m/s for the non-paretic side, 3.30 ± 1.20 m/s for the paretic side, and 2.24 ± 0.18 for controls. SW velocity was significantly different in muscles of the paretic and non-paretic side (p < 0.001), but not between muscles of the non-paretic and controls (p = 0.47). As voluntary activation increased, SW velocity increased non-linearly, with an average power fit of r2 = 0.83 ± 0.09 for the non-paretic side, r2 = 0.61 ± 0.24 for the paretic side, and r2 = 0.24 ± 0.15 for the healthy age-matched controls. In active muscle (10, 25, 50, 75, 100% maximum voluntary contraction), there was no significant difference in SW velocity between the non-paretic, paretic, and control muscles.These findings suggest that stroke-impaired muscles have potentially altered muscle material properties, specifically stiffness, and that passive and active stiffness may contribute differently to total muscle stiffness.