Value of image enhancement of endoscopic ultrasound for diagnosis of gastrointestinal subepithelial lesions.

Objectives: Among subepithelial lesions (SELs), gastrointestinal stromal tumors (GISTs) should be identified and surgically treated at an early stage. However, it is difficult to diagnose SELs smaller than 20 mm. In recent years, endoscopic ultrasound (EUS) elastography (EUS-EG) and contrast-enhanced harmonic EUS (CH-EUS) have been reported to be useful for the diagnosis of SELs, although the diagnostic accuracy of a combination of EUS techniques with image enhancement is unknown. Methods: Patients with SELs who underwent EUS-guided tissue acquisition, EUS shear-wave elastography (EUS-SWE), EUS strain elastography (EUS-SE), and CH-EUS from January 2019 to June 2023 were enrolled. To assess the diagnostic accuracy for differentiating GISTs from other SELs, shear-wave velocity on EUS-SWE, the strain ratio on EUS-SE, and vascularity on CH-EUS were determined and their diagnostic accuracies were compared. Results: Forty-three patients were enrolled. When the cut-off value was set at 3.27 m/s, the sensitivity, specificity, and diagnostic accuracy of shear-wave velocity were 28.6%, 86.2%, and 34.9%, respectively. When the cut-off value was set at 3.79, the sensitivity, specificity, and diagnostic accuracy of the strain ratio were 93.1%, 64.3%, and 83.7%, respectively. The sensitivity, specificity, and diagnostic accuracy of CH-EUS were 79.3%, 92.3%, and 83.7%, respectively. When EUS-SE was combined with CH-EUS, the sensitivity and diagnostic accuracy were the highest among binary combinations of image enhancement modalities. Conclusions: EUS-SE and CH-EUS are useful for differentiating GISTs from other SELs. Furthermore, the use of both modalities may further improve the identification of GISTs.

Diagnostic accuracy of endoscopic ultrasonographic shear wave elastography for assessing early chronic pancreatitis using the Japanese diagnostic criteria 2019.

Background and Aim: Endoscopic ultrasound shear wave elastography (EUS-SWE) can facilitate an objective evaluation of pancreatic fibrosis. Although it is primarily applied in evaluating chronic pancreatitis, its efficacy in assessing early chronic pancreatitis (ECP) remains underinvestigated. This study evaluated the diagnostic accuracy of EUS-SWE for assessing ECP diagnosed using the Japanese diagnostic criteria 2019. Methods: In total, 657 patients underwent EUS-SWE. Propensity score matching was used, and the participants were classified into the ECP and normal groups. ECP was diagnosed using the Japanese diagnostic criteria 2019. Pancreatic stiffness was assessed based on velocity (Vs) on EUS-SWE, and the optimal Vs cutoff value for ECP diagnosis was determined. A practical shear wave Vs value of ≥50% was considered significant. Results: Each group included 22 patients. The ECP group had higher pancreatic stiffness than the normal group (2.31 ± 0.67 m/s vs. 1.59 ± 0.40 m/s, p < 0.001). The Vs cutoff value for the diagnostic accuracy of ECP, as determined using the receiver operating characteristic curve, was 2.24m/s, with an area under the curve of 0.82 (95% confidence interval: 0.69-0.94). A high Vs was strongly correlated with the number of EUS findings (rs = 0.626, p < 0.001). Multiple regression analysis revealed that a history of acute pancreatitis and ≥2 EUS findings were independent predictors of a high Vs. Conclusions: There is a strong correlation between EUS-SWE findings and the Japanese diagnostic criteria 2019 for ECP. Hence, EUS-SWE can be an objective and invaluable diagnostic tool for ECP diagnosis.

Improving the diagnostic strategy for thyroid nodules: a combination of artificial intelligence-based computer-aided diagnosis system and shear wave elastography.

PURPOSE: Thyroid nodules are highly prevalent in the general population, posing a clinical challenge in accurately distinguishing between benign and malignant cases. This study aimed to investigate the diagnostic performance of different strategies, utilizing a combination of a computer-aided diagnosis system (AmCAD) and shear wave elastography (SWE) imaging, to effectively differentiate benign and malignant thyroid nodules in ultrasonography. METHODS: A total of 126 thyroid nodules with pathological confirmation were prospectively included in this study. The AmCAD was utilized to analyze the ultrasound imaging characteristics of the nodules, while the SWE was employed to measure their stiffness in both transverse and longitudinal thyroid scans. Twelve diagnostic patterns were formed by combining AmCAD diagnosis and SWE values, including isolation, series, parallel, and integration. The diagnostic performance was assessed using the receiver operating characteristic curve and area under the curve (AUC). Sensitivity, specificity, accuracy, missed malignancy rate, and unnecessary biopsy rate were also determined. RESULTS: Various diagnostic schemes have shown specific advantages in terms of diagnostic performance. Overall, integrating AmCAD with SWE imaging in the transverse scan yielded the most favorable diagnostic performance, achieving an AUC of 72.2% (95% confidence interval (CI): 63.0-81.5%), outperforming other diagnostic schemes. Furthermore, in the subgroup analysis of nodules measuring <2 cm or 2-4 cm, the integrated scheme consistently exhibited promising diagnostic performance, with AUCs of 74.2% (95% CI: 61.9-86.4%) and 77.4% (95% CI: 59.4-95.3%) respectively, surpassing other diagnostic schemes. The integrated scheme also effectively addressed thyroid nodule management by reducing the missed malignancy rate to 9.5% and unnecessary biopsy rate to 22.2%. CONCLUSION: The integration of AmCAD and SWE imaging in the transverse thyroid scan significantly enhances the diagnostic performance for distinguishing benign and malignant thyroid nodules. This strategy offers clinicians the advantage of obtaining more accurate clinical diagnoses and making well-informed decisions regarding patient management.

Doppler ultrasound imaging and shear wave elastography for evaluation of interstitial fibrosis/tubular atrophy in IgA nephropathy.

PURPOSE: The purpose of this study was to explore the value of Doppler ultrasound imaging and shear wave elastography (SWE) in evaluating renal interstitial fibrosis/tubular atrophy (IFTA). METHODS: During April 2019 and November 2023, biopsy-proven IgA nephropathy (IgAN) patients were enrolled in our study. Conventional ultrasound, Doppler ultrasound imaging and SWE measurements were performed, and related parameters were collected. According to the Oxford classification of IgAN, interstitial fibrosis/tubular atrophy (T) lesions were grouped into T0, T1 and T2 group. Receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic accuracy of SWE in identifying IFTA. RESULTS: A total of 100 IgAN patients were enrolled in the final cohort. 67 patients were in the T0 group, and 33 patients were in the T1/T2 group. The average SWE values were 42.17 ± 9.11 kPa in the T0 group and 36.83 ± 10.32 kPa in the T1/T2 group (p = 0.01). Multivariate logistic regression revealed that the SWE value and end diastolic velocity (EDV) of the interlobar artery were found to be independent risk factors for IFTA. For the diagnosis of IFTA, the area under the ROC curve (AUC) of SWE alone was 0.652, whereas the AUC of SWE in combination with the EDV was 0.807 (p = 0.008). CONCLUSION: The combination of Doppler ultrasound imaging and SWE measurements could improve the diagnostic performance of quantitative assessment of IFTA in IgAN patients.

Assessing Placental Shear Wave Elastography as a Tool for Evaluating Preeclampsia.

Background Hypertensive disorders of pregnancy, especially its dreaded complication preeclampsia, remain a major cause of morbidity and mortality for both the mother and the fetus. Existing tools for the prediction of preeclampsia remain inadequate in their sensitivity and specificity. Hence, there is an urgent need for a reliable, economically feasible, and objective marker for its diagnosis/early prediction. In this regard, shear wave elastography has shown great promise. Shear wave elastography is a novel method to quantify tissue stiffness, which is objective and has significantly lower inter-observer variability. Objectives We aim to quantify the tissue elasticity using point shear wave elastography (pSWE) in the placentas of diagnosed cases of preeclampsia and to compare them with the placentas of healthy controls in order to evaluate if there is a significant statistical difference between the two. Materials and methods This comparative study was conducted at the Department of Radiodiagnosis, Dr. D. Y. Patil Medical College, Hospital and Research Centre, Pune, India, from August 2022 to July 2024. The study included 60 participants, divided into two groups: 30 patients with preeclampsia and 30 healthy pregnancies. Placental stiffness was measured using a Samsung HS70A ultrasound machine (Samsung Electronics Pvt. Ltd., Seoul, South Korea), and pSWE was performed with a curvilinear probe. Data was analyzed using IBM SPSS Statistics for Windows, Version 21 (Released 2012; IBM Corp., Armonk, New York, United States), and the significance of differences between the two groups was assessed using an independent t-test with a p-value of <0.05, considered statistically significant. Results The mean placental stiffness, measured in kilopascals (kPa), was significantly higher in the preeclampsia group (11.71 ± 1.52 kPa) in comparison to the healthy group (3.36 ± 0.66 kPa) (p = 0.001). Patients suffering from preeclampsia were found to have significantly higher levels of placental stiffness. Conclusion Early diagnosis remains key to managing preeclampsia so that adequate monitoring and treatment could be provided to the patients. Our study showed that there is a significant statistical difference in the placental stiffness in patients with preeclampsia in comparison to a healthy placenta. Hence, shear wave elastography can be used as a supplementary tool to aid in the diagnosis/prediction of preeclampsia.

The diagnostic value and clinical relevance of high frequency ultrasound and shear wave elastography in systemic sclerosis: an observational monocentric study.

To unravel the features of skin involvement in patients with systemic sclerosis (SSc) by high frequency ultrasound (HFU) and shear wave elastography (SWE). To assess the ultrasound capabilities to distinguish SSc patients from healthy controls (HCs). We recruited a cohort of SSc patients in this cross-sectional study. HFU and SWE were used to quantify skin thickness and skin stiffness. Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic capabilities of ultrasound in SSc. The correlation analysis was used to evaluate the clinical relevance of ultrasound measurements in SSc. 20 consecutive SSc patients and 20 age-, gender- and body mass index-matched HCs were included. The skin thickness and stiffness were significantly greater in SSc patients compared with HCs. Patients with high disease activity had higher skin thickness and stiffness compared with patients with low disease activity. The area under the ROC curve (AUC) of the dorsum of middle fingers assessed by HFU was 0.847 (95% CI, 0.761-0.933). The AUC of the forearms and dorsum of hands assessed by SWE were 0.909 (95% CI, 0.829-0.989) and 0.879 (95% CI, 0.807-0.951). Further, the combined HFU and SWE tests displayed the best diagnostic performance with an AUC of 0.980 (95% CI, 0.939-1.000). A significant positive correlation between the ultrasound measurements and the modified Rodnan skin score (mRSS) was observed. The application of ultrasound can assist with disease diagnosis, it is necessary to develop a standard operating protocol to help with future implementation of ultrasound in SSc.

Effects of High-intensity Continuous Ultrasound on Infrapatellar Fat Pad Stiffness and Gliding in Healthy Participants: A Randomized, Single-blind, Placebo-controlled Crossover Trial.

OBJECTIVE: Ultrasound therapy effectively treats a joint range of motion limitation and pain originating from soft tissue in knee osteoarthritis (OA). Few interventional studies have focused on the infrapatellar fat pad (IFP), and the effects of high-intensity continuous ultrasound (HICUS) on IFP stiffness and gliding have not been investigated. Therefore, we aimed to determine the effects of HICUS on IFP stiffness and gliding. METHODS: This single-blind, randomized, controlled crossover study involved 24 healthy participants. The HICUS and placebo conditions were applied to the knee joint on 2 different days. HICUS was performed (1 MHz, 2.5 W/cm², duty cycle 100%, 5 min) using an ultrasound machine equipped with an applicator and adsorption-type fixed automatic rotation irradiation function. The main outcomes were IFP stiffness and gliding measured at 10 degrees and 120 degrees knee flexion. Gliding was measured as the difference between the patellar-tendon tibial angles at 10 degrees and 120 degrees knee flexion. Measurements were performed before (T1), immediately after (T2), and 15 min after (T3) treatment. RESULTS: Two-way repeated measures analysis of variance showed a significant interaction of IFP stiffness at 10 degrees knee flexion; post-test results showed that HICUS decreased stiffness at T2 and T3. There was no significant difference at 120 degrees. A significant interaction of gliding was observed under the HICUS condition. Post-tests showed that HICUS significantly improved gliding at T2 and T3. CONCLUSION: HICUS is a simple, safe intervention for improving IFP stiffness and gliding in healthy participants, with sustained effects. Further studies are needed to evaluate its efficacy in patients.

Attenuation Measuring Ultrasound Shearwave Elastography (AMUSE) as Noninvasive Imaging Biomarker for Liver Acute Cellular Rejection.

OBJECTIVE: There are over 9000 liver transplants in the United States per year, with acute cellular rejection (ACR) being a prevalent early post-transplant complication (20%-40%) treated using corticosteroids. Ischemia-reperfusion injury (IRI), another early post-transplant pathology, has similar laboratory results but typically resolves without therapy. ACR confirmation requires invasive liver biopsy, bearing risks like hemorrhage and pneumothorax. Attenuation Measuring Ultrasound Shearwave Elastography (AMUSE) assesses shear wave velocity (c) and attenuation (α) without rheological models and have shown potential for noninvasive tissue characterization. METHODS: We analyzed 58 transplanted livers suspected for ACR by comparing AMUSE measurements to biopsy findings. Thirteen patients underwent longitudinal tracking from ACR diagnosis on day 7 to therapy initiation and repeat biopsy on day 14. Statistical methods and support vector machine (SVM) were used for performance analysis. RESULTS: AMUSE measurements at 100, 200, and 300 Hz showed statistical significance (p < 0.001) for ACR presence, with 200 Hz exhibiting the highest Spearman correlation coefficients for c and α (0.68 and -0.83). High c (> 2.2 m/s) and low α (< 130 Np/m) at 200 Hz correlated with ACR diagnostic, while low c and high α indicated no ACR. Combining c and α into a single biomarker α/c improved patient differentiation, yielding an F1-score of 0.97. SVM was used to evaluate AMUSE ACR staging capabilities using all available frequencies, reaching 0.95 F1-score for categorical classification, with an AUROC of 0.99. When evaluating the presence of ACR the SVM reached 0.99 F1-score, with 1.00 sensitivity/recall. CONCLUSION: These findings support the use of AMUSE potential for detection and staging of liver ACR.

Comparison of Two-Dimensional Shear Wave Elastography Between Two Different Instruments for Hepatocellular Carcinoma Patients.

OBJECTIVES: This study aimed to investigate and compare 2-dimensional shear wave elastography (2D-SWE) measurements and influencing factors among 2 different devices and to evaluate the ability and influencing factors of these measurements to assess liver fibrosis. METHODS: From October 2022 to September 2023, 290 hepatocellular carcinoma (HCC) patients and 30 healthy volunteers were prospectively included. The 2D-SWE measurements were performed using AixPlorer V (SEmean) and APLIO i900 (CEmean). This study compared 2D-SWE measurements between instruments for evaluating the liver fibrosis stage and analyzed the potential influencing factors. RESULTS: The 2D-SWE measurements obtained by the 2 instruments were significantly different (P < .001), but the differences were significant only for patients with stage F4 liver fibrosis (P < .001) and not for volunteers or patients with stage F0-F3 liver fibrosis (all P > .050). Multivariate linear regression analysis revealed that the factors independently influencing the SEmean were alanine aminotransferase (ALT) (P = .034) and liver fibrosis stage (P < .001), while fibrosis stage (P = .028) was the only factor influencing the CEmean. CONCLUSIONS: Although 2D-SWE from the 2 different instruments was capable of detecting liver fibrosis, it yielded varying results in HCC patients. These discrepancies were predominantly observed in patients with F4 liver fibrosis but not in healthy adults or patients with F0-F3 liver fibrosis. One potential contributing factor to the differences between instruments could be ALT levels.

The Impact of Fu's Subcutaneous Needling on Lower Limb Muscle Stiffness in Knee Osteoarthritis Patients: Study Protocol for a Pilot Randomized Controlled Trial.

Background: Knee osteoarthritis (OA) is a leading cause of disability worldwide, with clinicians often observing increased muscle stiffness associated with joint pain and dysfunction. This study examines the impact of Fu's Subcutaneous Needling (FSN), a non-pharmacological technique, on muscle stiffness in the lower limbs of individuals with knee OA. Materials and Methods: This study protocol is a pilot, single-center, randomized controlled trial. Sixty knee OA patients will be allocated equally for FSN or electroacupuncture (EA) treatments. Interventions will be applied thrice weekly for the first two weeks and twice weekly for the subsequent two weeks for a total of ten sessions. Assessments will be conducted at baseline, post-initial session, after four weeks of intervention, and at the end of a four-week follow-up. The primary outcome will be the muscle stiffness in the lower extremities, as measured by shear wave elastography (SWE). Secondary outcomes include response rate, a reduction in the mean pain intensity on the Numerical Rating Scale (NRS) by at least two points and on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function subscale by six points at week four compared with baseline. Weekly monitoring of the NRS and WOMAC scores will determine the rapidity of pain alleviation and functional improvement, along with 12-item short-form (SF-12) score changes from baseline to week four. Results: This is the first standardized protocol examining the effects of FSN on lower limb muscle stiffness in patients with knee OA by SWE. We hypothesize that FSN could outperform EA in alleviating lower limb stiffness associated with knee OA. Findings will contribute to the body of knowledge regarding the efficacy of acupuncture-derived interventions in managing muscle stiffness and may guide future research directions. Study Registration: The trial has been registered on the Chinese Clinical Trial Registry (Registered number: ChiCTR2300073615). Registered 17 July 2023.

Comparison of US elastography and chemical shift magnetic resonance imaging in multifidus muscle fatty degeneration.

OBJECTIVE: The purpose of this study was to investigate the feasibility of the use of shear wave elastography (SWE) in comparison to chemical shift encoding (CSE) magnetic resonance imaging (MRI) for the evaluation of multifidus muscle fatty degeneration in patients with chronic low back pain. METHOD: Multifidus muscles were evaluated with the CSE-MRI and SWE examinations in control and patient groups. With the in-phase and out-phase sequences in CSE-MRI, signal intensity index (SII), and signal intensity suppression ratio (SISR) values; with the SWE method, shear wave velocity values were determined. Differences in the mean values of these parameters per level and study group were analyzed by Student's t-test. RESULTS: SWE revealed significantly lower stiffness at the L2-3 level, consistent with the signal index values (SII-SISR) showing increased fatty infiltration on MRI in the patient group. No such relationship was found at the L4-5 level or in control group. CONCLUSIONS: SWE may be a promising method to show muscle fatty infiltration at L2-3 level in patients with chronic low back pain.

OBJETIVO: Investigar la viabilidad del uso de la elastografía de ondas de corte en comparación con la resonancia magnética con codificación de desplazamiento químico (RM-CDQ) para la evaluación de la degeneración grasa del músculo multífido en pacientes con dolor lumbar crónico. MÉTODO: Los músculos multífidos se evaluaron con RM-CDQ y elastografía de ondas de corte en los grupos de control y de pacientes. Se consideraron las secuencias en fase y fuera de fase en RM-CDQ, y los valores del índice de intensidad de señal y del índice de supresión de intensidad de señal; con el método de elastografía de ondas de corte se determinaron los valores de velocidad de onda de corte. Las diferencias en los valores medios de estos parámetros por nivel y por grupo de estudio se analizaron mediante la prueba t de Student. RESULTADOS: La elastografía de ondas de corte reveló una rigidez significativamente menor en el nivel L2-3, consistente con los valores de los índices de señal que muestran una mayor infiltración grasa en la RM en el grupo de pacientes. No se encontró tal relación en el nivel L4-5 ni en el grupo de control. CONCLUSIONES: La elastografía de ondas de corte puede ser un método prometedor para mostrar la infiltración grasa muscular a nivel L2-3 en pacientes con dolor lumbar crónico.

The effect of tongue-to-palate on deep neck flexor activity.

Deep neck flexor (DNF) muscles contribute to cervical stability and proprioception. Reduced muscle strength and endurance lead to faulty movement patterns, muscle imbalances, and dysfunction. Potentially, the orofacial muscles contribute to cervical strength by providing stability through muscular connections. This study examined effects of tongue muscle activity on cervical spine muscular stiffness. Twenty-three healthy subjects assumed three supine positions [at rest (AR), chin tuck (CT), and head lift (HL)] with and without tongue-to-palate pressure. The DNF stiffness was measured using shear wave elastography. Without tongue-to-palate, stiffness increased with CT and HL compared to AR (p <0.001) but not between CT and HL (p = 0.22). Tongue-to-palate increased stiffness AR (p <0.001) but not during CT (p = 0.95) or HL (p = 0.67). Stiffness levels between the AR and HL conditions during tongue-to-palate performance did not differ (p = 0.734), but CT stiffness was significantly greater than AR (p = 0.029) with tongue-to-palate. Tongue-to-palate AR increases DNF stiffness to a similar level as HL with or without tongue-to-palate, while CT with or without tongue-to-palate resulted in the highest stiffness levels. Tongue-to-palate pressure AR or with CT performance may be alternatives to HL strengthening in healthy necks. This may be a useful strategy to increase cervical stability during loads on the cervical spine.

Assessment of the liver with two-dimensional shear wave elastography following COVID-19 infection: A pilot study.

Introduction/Purpose: The coronavirus disease (COVID-19) is a widely spread viral infectious disease, which can impact multiple organs, including the liver. Elevated liver enzymes have been reported in COVID-19 patients; however, potential changes in liver stiffness following the viral infection remain uncertain. The main aim of this pilot study was to determine if there is a significant difference in liver stiffness between individuals who have never been infected with COVID-19 and those who had been infected with COVID-19 <6 months, experiencing only mild symptoms. The secondary aim was to compare the liver stiffness between participants infected with COVID-19 depending on the elapsed time since infection. Methods: Two-dimensional shear wave elastography (2D-SWE) was performed prospectively on 68 participants. Thirty-four participants had been infected with COVID-19 (all for <6 months) (COVID-19 group), and another 34 had never been infected with COVID-19 (control group). The mean 2D-SWE measurements of both the COVID-19 group and the control group were compared using an independent t-test. The mean 2D-SWE measurements of the COVID-19 subgroups A (<2 months), B (2 to <4 months) and C (4 to <6 months) were compared using a one-way ANOVA test (P < 0.05). Results: The (mean ± standard deviation) liver stiffness (kPa) of the COVID-19 group (5.26 ± 1.63 kPa) was significantly higher than the control group (4.30 ± 0.96 kPa) (P = 0.005). There was no significant difference in liver stiffness among subgroups A (5.20 ± 1.79 kPa), B (4.70 ± 1.53 kPa) and C (5.96 ± 1.48 kPa) (P = 0.143) respectively. Discussion: The mean liver stiffness of 4.30 ± 0.96k Pa in the control group showed a high probability of being normal as per guidelines. Conversely, the mean liver stiffness of 5.26 ± 1.63 kPa in the COVID-19 group exhibited a statistically significant increase compared to the control group. However, compensated advanced chronic liver disease was ruled out without other known clinical signs, as per guidelines. Conclusion: A statistically significant increase in liver stiffness value was observed in the post-COVID-19 infection group compared to the group who had never been infected. This highlights the potential for short-term impact on liver stiffness associated with COVID-19 infection. However, it is unclear if these changes in liver stiffness are associated with liver injury. Further study is warranted to investigate the effects of COVID-19 infection and its long-term impact on the liver.

Spleen shear wave elastography measurements do not correlate with histological grading of liver fibrosis in Fontan physiology: a preliminary investigation.

BACKGROUND: Elevated spleen stiffness may be seen in patients with portal hypertension due to cirrhosis. In patients with Fontan physiology, elevated liver stiffness has been shown to correlate poorly with liver fibrosis. It is unknown whether spleen stiffness may instead serve as a surrogate marker of liver fibrosis in these patients. OBJECTIVE: To compare spleen stiffness determined by shear wave elastography (SWE) with histological findings of an ultrasound-guided liver biopsy in patients who had undergone Fontan palliation as a potential surrogate for Fontan-associated liver disease. MATERIALS AND METHODS: This was an IRB-approved single-center, retrospective study. Patients with Fontan palliation who had undergone both a spleen SWE study and a percutaneous liver biopsy between 2016 and 2020 were included. Biopsy, performed during cardiac catheterization, within 3 months of the SWE was required for inclusion. Using Kruskal-Wallis tests, spleen stiffness was compared with three liver biopsy scoring methods: Ishak, METAVIR, and congestive hepatic fibrosis score (CHFS). When available, Pearson's correlation was also used to compare collagen deposition determined using Sirius Red stain (%SR) with SWE values. A P-value < 0.05 was considered statistically significant. RESULTS: Twenty-two patients (15 males) were included in the study, with a median age of 17 years (IQR is 14.8-20.5 years; age range: 7 years to 30.2 years). The median spleen stiffness was 2.94 m/s (IQR: 2.57-3.61 m/s; range: 1.48-4.27 m/s). The median Fontan pressure was 11 mm Hg (IQR: 10-13.3 mm Hg; range: 7-19 mm Hg) obtained within a median of 10 days (IQR: 1-41 days) of SWE. Splenic stiffness did not correlate with the extent of fibrosis determined by histology (all P > 0.05). There was also no statistically significant correlation between the %SR staining and SWE-determined spleen stiffness (Pearson's correlation of 0.165, P = 0.59, n = 13). CONCLUSIONS: In this preliminary study, SWE spleen stiffness values did not correlate with biopsy-determined scoring of liver fibrosis in patients with Fontan physiology.

Study on the correlation between shear wave elastography and MRI grading of meniscal degeneration.

BACKGROUND: Shear Wave Elastography (SWE) offers quantitative insights into the hardness and elasticity characteristics of tissues. The objective of this study is to investigate the correlation between SWE of the menisci and MRI-assessed degenerative changes in the menisci, with the aim of providing novel reference source for improving non-invasive evaluation of meniscal degenerative alterations. METHODS: The participants in this study were selected from patients who underwent knee joint MRI scans at our hospital from February 2023 to February 2024. The anterior horns of both the medial and lateral menisci were evaluated using SWE technique. The differences in elastic values of meniscus among different MRI grades were compared. The correlation between elastic values and MRI grades, as well as various parameters, was analyzed. Using MRI Grade 3 as the gold standard, the optimal cutoff value for meniscal tear was determined. The intraclass correlation coefficient (ICC) was employed to evaluate the reliability of repeated measurements performed by the same observer. RESULTS: A total of 104 female participants were enrolled in this study, with 152 lateral menisci (LM) and 144 medial menisci (MM) assessed. For the male group, 83 individuals were included, with 147 LM and 145 MM evaluated. The results demonstrated statistically significant differences in the elasticity values of the menisci at the same anatomical sites across different MRI grades (P < 0.001). Within the same grade, the MM had higher elasticity values than the LM, showing a statistically significant difference (P < 0.001). The elasticity values of the menisci were higher in males compared to females. There were statistically significant positive correlations between the elasticity values of the menisci and age, BMI, and MRI grade. The ICC for repeated measurements within the observer demonstrated good reliability (> 0.79). CONCLUSIONS: The meniscal elasticity values measured by SWE exhibit a significant positive correlation with the grades of degeneration assessed by MRI. Furthermore, the elasticity values of the meniscus are found to increase with advancing age and elevated BMI.

Quantifying Active and Passive Stiffness in Plantar Flexor Muscles Following Intermittent Maximal Isometric Contractions Using Shear Wave Elastography.

OBJECTIVE: This study aimed: (i) to investigate the impact of fatigue, triggered by maximal isometric contraction exercises, on the active and passive stiffness of plantar flexors (PF), and (ii) to examine the relationship between changes in mechanical parameters and neuromuscular alterations after fatigue. METHODS: A healthy cohort (n = 12; age = 27.3 ± 5.5 y; BMI = 24.4 ± 2.35 kg/m²) was instructed to perform 60 isometric contractions, each lasting 4 s with a 1-s rest interval, using an ergometer. Several measures were taken before and after the fatigue protocol. First, the stiffness of the PF-tendon complex (PFC) was quantified during passive ankle mobilization both during and after the fatigue protocol using the ergometer. Additionally, from shear wave elastography, the active and passive stiffness of the gastrocnemius medialis (GM) were measured during passive ankle mobilization and isometric maximal voluntary contraction (MVC), respectively. Finally, the peak torque and the rate of torque development (RFD) of PF were assessed during the MVC using the ergometer. Ankle muscle activities (surface electromyograph [SEMG]) were recorded during all evaluations using electromyography. RESULTS: After the fatigue protocol, the results revealed a decline in active stiffness, peak torque of PF, RFD and SEMG activity of the GM (p < 0.001). Furthermore, significant correlation was identified between the decrease of the peak torque of PF and the active stiffness of the GM (r = 0.6; p < 0.05). A decrease in the PFC stiffness (p < 0.001) and a decrease in the shear modulus of the GM at 20° (p < 0.001) were also observed. CONCLUSION: Isometric fatiguing exercises modify the mechanical properties of both the contractile and elastic components. Notably, decreases in both passive and active stiffness may be critical for athletes, as these changes could potentially increase the risk of injury.

The effects of a 12-week combined motor control exercise and isolated lumbar extension intervention on lumbar multifidus muscle stiffness in individuals with chronic low back pain.

Introduction: Exercise therapy is the primary endorsed form of conservative treatment for chronic low back pain (LBP). However, there is still conflicting evidence on which exercise intervention is best. While motor control exercise can lead to morphological and functional improvements of lumbar multifidus muscle in individuals with chronic LBP, the effects of exercise prescription on multifidus stiffness assessed via shear wave elastography are still unknown. The primary aim of this study is to determine the effects of a combined motor control and isolated lumbar extension (MC + ILEX) intervention on lumbar multifidus muscle stiffness. Methods: A total of 25 participants aged 18 to 65 were recruited from local orthopedic clinics and the university community with moderate to severe non-specific chronic LBP. Participants performed a 12-week MC + ILEX intervention program. Stiffness of the lumbar multifidus muscle (primary outcome) at L4 and L5 was obtained at baseline, 6-week, and 12-week using shear wave elastography. Changes in stiffness ratio (e.g., ratio of lumbar multifidus muscle stiffness from rest to contracted) were also assessed at both time points. Pre to post-intervention changes in lumbar multifidus muscle stiffness were assessed using a one-way repeated measure ANOVA. Results: Following the 12-week intervention, there were no statistically significant changes in lumbar multifidus muscle stiffness at rest on the right side at L4 (p = 0.628) and the left side at L4 and L5 (p = 0.093, p = 0.203), but a statistically significant decrease was observed on the right side at L5 (p = 0.036). There was no change in lumbar multifidus muscle stiffness ratio. Conclusion: This study provides preliminary evidence to suggest that a 12-week MC + ILEX intervention had minimal effect on lumbar multifidus muscle stiffness in individuals with chronic LBP. Further investigations are needed to confirm our findings and clarify the relationship between muscle stiffness and functional outcomes.

Diagnostic potential of Shear wave elastography for central precocious puberty with breast development.

PURPOSE: The aim of this study was to assess the accuracy and diagnostic use of shear wave elastography (SWE) in differentiating central precocious puberty (CPP) with breast development and to analyze the correlations between sex hormone levels and SWE parameters. METHODS: A total of 227 participants were included in this retrospective case-control study, including 113 girls with genuine precocious puberty breast development (the CPP group) and 114 with non-genuine precocious puberty breast development (the non-CPP group). The participants underwent clinical assessment, hormonal assays, and SWE using advanced ultrasound equipment. Statistical analyses, including t-tests, correlation analysis, logistic regression, and receiver operating characteristic (ROC) analysis, were performed to evaluate the diagnostic value of SWE and sex hormone levels in differentiating CPP with breast development. RESULTS: There were no significant differences in clinical characteristics between the two groups. The sex hormone levels of estradiol, testosterone, luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin in the CPP group were significantly higher than those in the non-CPP group. Shear wave velocity (SWV) Maximum (Max), SWV Minimum (Min), SWV Mean, SWV standard deviation (SD), and SWV coefficient of variation in the CPP group were significantly higher than in the non-CPP group. Correlation analysis demonstrated significant positive correlations between LH, FSH, estradiol, and testosterone levels with various SWE parameters, indicating their clinical relevance. Logistic regression analysis identified substantial predictive potential of sex hormone levels and SWE parameters for genuine precocious puberty breast development. Additionally, the ROC analysis highlighted a high predictive value of the combined model of SWE parameters, with an area under the curve (AUC) of 0.903. CONCLUSION: The study underscores the correlations between sex hormone levels and SWE parameters. The superior predictive performance of the combined model of SWE parameters emphasizes the value of integrated SWE assessments for improving the accuracy of diagnosing genuine precocious puberty breast development.

Inversion method of NHV based on novel model parameter space acquisition strategy and its application in the Tonghai basin site in Yunnan, China.

The imaging of subsurface soil velocity structures from ambient noise inversion is a difficult problem. Few recording points and a simplified 1-D layered profile lead to important non-uniqueness. From our point of view, improving the reliability of processing methods of the observed data to obtain noise horizontal-to-vertical spectral ratio (NHV) curves and setting a complete model parameter space are important tasks to reduce the non-uniqueness of inversion. In this study, using a local site near the border of the Tonghai Basin, China, as a case study, we first demonstrate how to identify and mitigate the influence of industrial sources using surface observations to obtain more reliable NHV curves. Then, a new strategy to determine model parameter space is proposed, that is, stratifying soil layers based on the number of NHV peaks and determining the shear wave velocities, thicknesses, and their ranges based on the empirical relationship between sedimentary thickness and resonant frequency (h-f r). Subsequently, combining the model parameter space acquisition strategy with the NHV inversion, a novel NHV inversion approach is developed and applied to obtain the 2-D V S profile of the investigated Tonghai site. The inverted 2-D V S profile aligns favorably with the frequency-depth conversion results of the measured NHV curves (NHV-profiling) and the measured borehole profiles, affirming the reliability of the proposed NHV inversion method. Finally, by comparing the empirical transfer functions from the strong-motion recordings, we validated the applicability of the inverted models for characterizing site effects. The model parameter space acquisition strategy proposed in this paper and the analysis procedure of the observed data are also applicable to other study areas, which can provide a referable approach to quickly and effectively acquire the soil layer velocity structure of the site.

Predicting clinically significant prostate cancer in elderly patients: A nomogram approach with shear wave elastography.

PURPOSE: This study was to construct a nomogram utilizing shear wave elastography and assess its efficacy in detecting clinically significant prostate cancer (csPCa). METHODS: 290 elderly people with suspected PCa who received prostate biopsy and shear wave elastography (SWE) imaging were respectively registered from April 2022 to December 2023. The elderly participants were stratified into two groups: those with csPCa and those without csPCa, which encompassed cases of clinically insignificant prostate cancer (cisPCa) and non-prostate cancer tissue, as determined by pathology findings. The LASSO algorithm, known as the least absolute shrinkage and selection operator, was utilized to identify features. Logistic regression analysis was utilized to establish models. Receiver operating characteristic (ROC) and calibration curves were utilized to evaluate the discriminatory ability of the nomogram. Bootstrap (1000 bootstrap iterations) was employed for internal validation and comparison with two models. A decision curve and a clinical impact curve were employed to assess the clinical usefulness. RESULTS: Our nomogram, which contained Emean, ΔEmean, prostate volume, prostate-specific antigen density (PSAD), and transrectal ultrasound (TRUS), showed better discrimination (AUC = 0.89; 95% CI: 0.83-0.94), compared to the clinical model without SWE parameters (p = 0.0007). Its accuracy, sensitivity and specificity were 0.83, 0.89 and 0.78, respectively. Based on the analysis of decision curve, the thresholds ranged from 5% to 90%. According to our nomogram, biopsying patients at a 20% probability threshold resulted in a 25% reduction in biopsies without missing any csPCa. The clinical impact curve demonstrated that the nomogram's predicted outcome is closer to the observed outcome when the probability threshold reaches 20% or greater. CONCLUSION: Our nomogram demonstrates efficacy in identifying elderly individuals with clinically significant prostate cancer, thereby facilitating informed clinical decision-making based on diagnostic outcomes and potential clinical benefits.