Shear Wave Elastography Imaging Research Articles

Properties of the iliotibial band and their relationships with gait parameters among patients with knee osteoarthritis.

This study aimed to determine the thickness and stiffness of the iliotibial band(ITB) in patients with knee osteoarthritis (KOA) and to identify the gait parameters that are associated with ITB properties. Eighteen female patients with radiographically diagnosed medial KOA and knee pain (age: 69.7 ± 5.9 years, body mass index: 23.0 ± 3.1 kg/m2 ) and 22 age-matched female individuals without knee pain (age: 69.1 ± 7.0 years, body mass index: 21.6 ± 3.6 kg/m2 ) were included. Shear wave elastography images were obtained at the height of the proximal pole of the patella with the participants in the supine position, and the ITB thickness and shear wave velocity, which is a surrogate measure of stiffness, were calculated. In patients with KOA, the knee and hip joint angles and moments during walking were calculated using a motion analysis system. The shear wave velocity was significantly higher in patients with KOA than in asymptomatic adults (11.3 ± 1.0 vs. 10.0 ± 1.8 m/s, respectively; p = 0.010); however, the thickness did not differ between them (2.1 ± 0.3 vs. 2.0 ± 0.3 mm, respectively; p = 0.705). The time-integral value of the knee adduction moment (β = 0.507, p = 0.032) and maximum value of the hip flexion moment (β = 0.498, p = 0.036) were associated with the shear wave velocity. Meanwhile, no parameters were associated with the thickness. The ITB was stiffer in patients with KOA than in asymptomatic adults; such a stiffer ITB was associated with greater knee adduction and hip flexion moments during walking. Clinical Significance: Greater mechanical loading was associated with a stifferITBin patients with KOA.

Comparison of non-invasive imaging methods and laboratory findings on non-alcoholic fatty liver disease (NAFLD) in childhood

Aim: Diagnosis and follow-up of non-alcoholic fatty liver disease in children with practical and non-invasive methods have been researched for many years. Ultrasonography (USG), Shear wave elastography (SWE), and Magnetic Resonance (MR) are thought to help demonstrate the impairment which is also displayed in liver function tests. This study aims to identify the most effective imaging method among liver scanning methods in exhibiting the fatty condition of the liver and laboratory tests.
 Material and Method: This study was carried out on a population of 84 children who applied to the clinic. The relationship between the diagnostic performances of three different noninvasive methods [USG, MR, and SWE] and liver function tests in children with suspected NAFLD was analyzed. Age, BMI (body mass index), waist circumference, gender, liver function tests, total cholesterol, triglyceride, and Homeostasis Model Assesment-Insulin Rezistance (HOMA-IR) parameters of NAFLD and control group were put into comparison and their relationship with USG, MR, and SWE imaging methods were also analyzed.
 Results: There is no statistically significant relationship between hepatosteatosis grade and the mean SWE (p>0.05) while there is a positive and statistically significant relationship between waist circumference and liver long axis values at 33.3% level (p: 0.036; p0.05).
 Conclusion: Abdominal USG, SWE, and dynamic MR examinations are very essential to demonstrate liver functions and liver pathology in children with non-invasive methods. It is also useful in patient follow-up. In this study, no difference was detected between SWE and MR findings, and we think that the SWE examination will be more suitable in estimating liver functions in follow-up as opposed to costly MR examination.

Diagnostic performance of C-TIRADS combined with SWE for the diagnosis of thyroid nodules.

ObjectiveTo explore the value of the optimal parameters of shear wave elastography (SWE) to enhance the identification of benign and malignant thyroid nodules by C-TIRADS.MethodsThe two-dimensional ultrasonography images and SWE images of 515 patients with a total of 586 thyroid nodules were retrospectively analyzed. The nodules were divided into the D ≤10 mm and D >10 mm groups according to size and were graded by C-TIRADS. With the pathological results as the gold standard, the receiver operating characteristic (ROC) curves were drawn, and the area under the curve (AUC) was calculated to compare the diagnostic performances of C-TIRADS, SWE, and the combination of the two on the benign and malignant thyroid nodules.ResultsThe ROC showed that the AUC of the maximum elastic modulus (0.875) was higher than that of the mean elastic modulus (0.798) and elasticity ratio (0.772), with an optimal cutoff point of 51 kPa, which was the optimal parameter to distinguish the malignant from the benign nodules (P < 0.001). In the D ≤10 mm group, the AUC of TIRADS combined with SWE (0.955) was elevated by 0.172 compared with the application of C-TIRADS alone (0.783), and the difference was statistically significant (P < 0.05). In the D >10 mm group, the AUC of TIRADS combined with SWE (0.904) was elevated by 0.076 compared with the application of C-TIRADS alone (0.828), and the difference was statistically significant (P < 0.05). Among all nodules, the application of C-TIRADS alone had a sensitivity of 88.14%, a specificity of 74.56%, and an accuracy of 85.50% in diagnosing benign and malignant thyroid nodules, while the sensitivity, specificity, and accuracy were 93.22%, 90.35%, and 92.66%, respectively, in combination with SWE.ConclusionThe diagnostic performance of SWE in combination with TIRADS was better than that of SWE or C-TIRADS alone. Here, SWE enhanced the diagnostic performance of C-TIRADS for the benign and malignant thyroid nodules, most significantly for nodules with D ≤10 mm.

Evaluating different combination methods to analyse ultrasound and shear wave elastography images automatically through discriminative convolutional neural network in breast cancer imaging

PurposeUltrasound (US) and Shear Wave Elastography (SWE) imaging are non-invasive methods used for breast lesion characterization. While US and SWE images provide both morphological information, SWE visualizes in addition the elasticity of tissue. In this study a Discriminative Convolutional Neural Network (DCNN) model is applied to US and SWE images and their combination to classify the breast lesions into malignant or benign cases. Furthermore, it is identified whether analysing only the region of the elastogram or including the surrounding B-mode image gives a superior performance.MethodsThe dataset used in this study consists of 746 images obtained from 207 patients comprising 486 malignant and 260 benign breast lesions. From each image the US and SWE image was extracted, once including only the region of the elastogram and once including also the surrounding B-mode image. These four datasets were applied individually to a DCNN to determine their predictive capability. Each the best US and SWE dataset were used to examine different combination methods with DCNN. The results were compared to the manual assessment by an expert radiologist.ResultsThe combination of US and SWE images with the surrounding B-mode image using two ensembled DCNN models achieved best results with an accuracy of 93.53 %, sensitivity of 94.42 %, specificity of 90.75 % and area under the curve (AUC) of 96.55 %.ConclusionThis study showed that using the whole US and SWE images through DCNN was superior to methods, in which only the region of elastogram was used. Combining breast cancer US and SWE images with two ensembled DCNN models in parallel improved the results. The accuracy, sensitivity and AUC of the best combination method were significantly superior to the results of using a single dataset through DCNN and to the results of the expert radiologist.

Convolutional Neural Network for Predicting Thyroid Cancer Based on Ultrasound Elastography Image of Perinodular Region.

We aimed to develop deep learning models based on perinodular regions' shear-wave elastography (SWE) images and ultrasound (US) images of thyroid nodules (TNs) and determine their performances in predicting thyroid cancer. A total of 1747 American College of Radiology Thyroid Imaging Reporting & Data System 4 (TR4) thyroid nodules (TNs) in 1582 patients were included in this retrospective study. US images, SWE images, and 2 quantitative SWE parameters (maximum elasticity of TNs; 5-point average maximum elasticity of TNs) were obtained. Based on US and SWE images of TNs and perinodular tissue, respectively, 7 single-image convolutional neural networks (CNN) models [US, internal SWE, 0.5 mm SWE, 1.0 mm SWE, 1.5 mm SWE, 2.0 mm SWE of perinodular tissue, and whole SWE region of interest (ROI) image] and another 6 fusional-image CNN models (US + internal SWE, US + 0.5 mm SWE, US + 1.0 mm SWE, US + 1.5 mm SWE, US + 2.0 mm SWE, US + ROI SWE) were established using RestNet18. All of the CNN models and quantitative SWE parameters were built on a training cohort (1247 TNs) and evaluated on a validation cohort (500 TNs). In predicting thyroid cancer, US + 2.0 mm SWE image CNN model obtained the highest area under the curve in 10 mm < TNs ≤ 20 mm (0.95 for training; 0.92 for validation) and TNs > 20 mm (0.95 for training; 0.92 for validation), while US + 1.0 mm SWE image CNN model obtained the highest area under the curve in TNs ≤ 10 mm (0.95 for training; 0.92 for validation). The CNN models based on the fusion of SWE segmentation images and US images improve the radiological diagnostic accuracy of thyroid cancer.

Comparison of preoperative penile elastographic ultrasound findings and pathological tissue results of patients implemented with penile prosthesis.

Histopathological analysis of the relationship between penile elastography and erectile dysfunction. 12 patients who applied to our clinic for erectile dysfunction in the last 1year and accepted this study were included. Preoperative two-dimensional shear wave elastography imaging was performed in 12 patients and recorded in the Pascal (kPa) unit. Approximately 0.5 × 0.5 × 0.5cm tissue samples were taken from the right and left cavernous tissue during penile prosthesis implantation operation. Tissue samples were sent to the pathology department. The percentage of the area covered by muscle fibers and elastic fibers in the corpus cavernosum was noted semi-quantitatively (ratio of muscle fibers and cavernous body elastic fiber score). All data obtained were compared with each other. Cavernous body elastic fiber score data(Grouped Score 1, 2 and 3) and percentage of cavernous body muscle fibers data (Grouped %10, %20, %30… %100) were compared with Shear wave elastography data (kPa). The results were not statistically significant according to the Kruskal Wallis Test. Cavernous body elastic fiber score and the percentage of cavernous body muscle fibers were also compared, it was not statistically significant according to the Kruskal Wallis test and Spearman's correlation test. Penile shear wave elastography can be used clinically to quantitatively assess the amount of smooth muscle cells and elastic fibers in the penis, but it deserves to be studied with a larger number of patients and a more specific interpretation of the pathology preparation.

Ultrasound shear wave elastography in pediatric stricturing small bowel Crohn disease: correlation with histology and second harmonic imaging microscopy.

Preclinical animal as well as small exploratory ex vivo and in vivo human studies have suggested that bowel wall shear wave speed (SWS) measurements may be a noninvasive biomarker of intestinal damage. To evaluate the relationships between bowel wall stiffness, measured using ultrasound shear wave elastography (SWE), and intestinal fibrosis and smooth muscle hypertrophy as determined by (1) histology and (2) second harmonic imaging microscopy (SHIM) in surgically resected ileal strictures from pediatric Crohn disease patients. Nineteen pediatric Crohn disease patients with symptomatic ileal strictures underwent research ultrasound examinations before surgical resection between December 2017 and September 2020. Two-dimensional SWE was performed through the area of the most severe stenosis, with measurements obtained from the bowel wall at the 9:00, 12:00 and 3:00 o'clock locations with 0%, 10% and 20% abdominal strain. Overall right lower quadrant stiffness also was documented. Median bowel wall and overall right lower quadrant SWS measurements were correlated with bowel wall histological scores of inflammation, fibrosis and smooth muscle proliferation as well as SHIM collagen signal. Diagnostic ultrasound SWE imaging was obtained from 18 participants. The median age was 16.8 years. There were negative correlations between histological mucosal active inflammation and both bowel wall SWS with 10% abdominal strain (r=-0.50, P = 0.04) and overall right lower quadrant SWS with 20% abdominal strain (r=-0.69, P = 0.002). There were positive correlations between histological muscularis propria inner layer smooth muscle hypertrophy and both median bowel wall SWS with 10% abdominal strain (r = 0.72, P = 0.002) and overall right lower quadrant SWS with 20% abdominal strain (r = 0.71, P = 0.002). There were no associations between ultrasound stiffness metrics and bowel wall SHIM collagen measurements. Bowel wall and overall right lower quadrant ultrasound stiffness measurements correlate with mucosal active inflammation and muscularis propria smooth muscle hypertrophy in pediatric stricturing ileal Crohn disease, but not with intestinal fibrosis.

Influence of the Field of View on Shear Wave Velocity Estimation

Abstract Tissue elasticity contains important information for physicians in diagnosis and treatment, and, e.g., can help in tumor detection because tumors are stiffer than healthy tissue. Ultrasound shear wave elastography imaging (US-SWEI) can be used to estimate tissue stiffness by measuring the velocity of induced shear waves. Commonly, a linear US probe is used to track shear waves at a high imaging frequency in 2D. Realtime US-SWEI is limited by the required time for data processing. Hence, reducing the imaging field of view (FOV) is beneficial as it decreases the size of the acquired data and thereby the acquisition, transfer and processing time. However, a decrease in the FOV has the disadvantage that shear waves are tracked over a smaller distance and thus, also fewer sampling points are available for velocity estimation. This trade-off between a smaller FOV and thus, a smaller data size, and the accuracy of shear wave velocity estimation is investigated in this work. For this purpose, shear waves were tracked with a linear US probe in gelatin phantoms with four different stiffness values. During data processing, we reduced the FOV virtually from 38.1mm to 2.1mm. It was found that a reduction of the FOV to 4.5mm leads to an overestimation of up to five times larger shear wave velocities but still allows to distinguish between phantoms of different stiffness. However, not all estimated velocity values could be clearly assigned to the correct stiffness value. The smallest studied FOV of 2.1mm was not sufficient for distinguishing between the phantoms anymore.

Differential Diagnosis Value of Shear-Wave Elastography for Superficial Enlarged Lymph Nodes.

ObjectivesTo evaluate the diagnostic efficiency and diagnostic threshold of conventional US and shear-wave elastography (SWE) in superficial enlarged lymph nodes (LNs).MethodsA total of 204 patients with superficial enlarged LNs were enrolled in this retrospective study aged 46.0 ± 15.2 years from March 2020 to March 2021. LNs with a long axis larger than 0.7 cm were considered as superficial enlarged. Before the histological biopsy, LNs that were considered suspicious according to both conventional US and SWE were included, while LNs with no or unclear pathological results, or with no satisfactory SWE images, were excluded. The conventional and 2-D SWE examinations were performed with Aplio i800 and Acuson sequoia equipped with i18LX5 linear-array transducer (5-18 MHz) and 10L4 linear-array transducer (4-10 MHz), respectively. Both E Median and Vs Median parameters were investigated by two senior ultrasound physicians. The pathological results were performed as the gold standard.ResultsVariables including transverse axis size, lymphatic hilum, L/T ratio, echogenicity, and color Doppler pattern were considered significant. The mean E Median value in benign, metastatic LNs, and lymphoma were 28.26 ± 8.87 kPa, 77.46 ± 22.85 kPa, and 50.37 ± 5.41 kPa (p <0.001), while Vs Median values were 3.02 ± 0.50 m/s, 4.87 ± 0.90 m/s, and 4.09 ± 0.22 m/s, respectively (p < 0.001). The diagnostic performance indicated the high sensitivity, specificity, PPV, NPV, and overall accuracy of conventional US combined with SWE. The optimal cutoff values of E Median and Vs Median for predicting malignant LNs were 42.90 kPa and 3.73 m/s, respectively. As AUC value, sensitivity, specificity, accuracy, PPV, and NPV revealed, the indexes of E Median were 0.976, 0.927, 0.975, 0.946, 0.983, and 0.897, respectively, while Vs Median were 0.970, 0.927, 0.963, 0.941, 0.975, and 0.895, respectively (p <0.001). The ROC curves of both E Median (AUC=0.976) Vs Median (AUC=0.970) suggested the remarkable diagnostic efficiency in distinguishing benignity between suspected malignant LNs.ConclusionsAbove results indicated that conventional US together with 2-D SWE could elevate the diagnostic performance. Meanwhile, the parameters of 2-D SWE including E Median and Vs Median could effectively assess malignant LNs, which provide valuable differentiating information in superficial enlarged LNs.

Shear wave elastography imaging in a porcine tendinopathy model.

To quantify the effect of structural damage in an ex vivo animal tendinopathy model using shear wave elastography (SWE). Sixteen porcine flexor tendons were injected with a 0.05mL bolus of 1.5% collagenase solution to induce focal structural damage without surfacing tears. Control tendons were injected with saline (n = 16). Eight tendons from each group were incubated at 37°C for 3.5h while the remaining 8 from each group were incubated for 7h. Tendons were mechanically stretched to 0% and 1% strain. Simultaneously, SWE was acquired proximal to, at, and distal to the injection site using a clinical ultrasound scanner. There were significant differences in SWS (saline > collagenase) at 1% strain and 7-h incubation for all three locations (PROX p = 0.0031, ROI p = 0.001, DIST p = 0.0043). There were also significant differences at 0% strain and 7h, but only at (p = 0.0005), and distal to (p = 0.0035), the injection site. No statistically significant differences were observed for 3.5-h incubation, at 0% or 1% strain. Collagenase-mediated structural damage does appear to convey decreased tissue elasticity on SWE when ex vivo tendons are incubated for 7h. These findings suggest that SWE may be a useful tool for predicting ultimate tissue strength in tendinopathic tissues. Pull-to-failure testing should be performed in the future and are expected to show that tendons with decreased SWS, and, therefore, decreased elasticity, rupture at lower pulls forces.

A paired comparison of nerve dimensions using B-Mode ultrasound and shear wave elastography during regional anaesthesia.

Shear wave elastography (SWE) presents nerves in colour, but the dimensions of its colour maps have not been validated with paired B-Mode nerve images. Our primary objective was to define the bias and limits of agreement of SWE with B-Mode nerve diameter. Our secondary objectives were to compare nerve area and shape, and provide a clinical standard for future application of new colour imaging technologies such as artificial intelligence. Eleven combined ultrasound-guided regional nerve blocks were conducted using a dual-mode transducer. Two raters outlined nerve margins on 110 paired B-Mode and SWE images every second for 20 s before and during injection. Bias and limits of agreement were plotted on Bland-Altman plots. We hypothesized that the bias of nerve diameter would be <2.5% and that the percent limits of agreement would lie ±0.67% (2 SD) of the bias. There was no difference in the bias (95% confidence interval (CI) limits of agreement) of nerve diameter measurement, 0.01 (-0.14 to 0.16) cm, P = 0.85, equivalent to a 1.4% (-56.6% to 59.5) % difference. The bias and limits of agreement were 0.03 (-0.08 to 0.15) cm2, P = 0.54 for cross-sectional nerve area; and 0.02 (-0.03 to 0.07), P = 0.45 for shape. Reliability (ICC) between raters was 0.96 (0.94-0.98) for B-Mode nerve area and 0.91 (0.83-0.95) for SWE nerve area. Nerve diameter measurement from B-Mode and SWE images fell within a priori measures of bias and limits of agreement.

Comparison of diagnostic value of SWE, FNA and BRAF gene detection in ACR TI-RADS 4 and 5 thyroid nodules.

To compare the diagnostic value of shear wave elastography (SWE), fine needle aspiration (FNA) and BRAF gene detection (BRAFV600E gene mutation detection) in ACR TI-RADS 4 and 5 thyroid nodules. SWE images, FNA cytological results and BRAF detection results of ACR TI-RADS 4 and 5 thyroid nodules confirmed by pathology were analyzed retrospectively. The receiver operating characteristic (ROC) curve was drawn to determine the best cutoff value of SWE Emax. In the combined diagnosis of SWE, FNA and BRAF, firstly, the nodules with BRAF gene mutation were included in the positive ones, secondly, the nodules with benign and malignant FNA were included in the FNA + SWE or FNA + SWE + BRAF negative and positive ones respectively, finally, for FNA uncertain nodules: those whose SWE Emax were less than or equal to the cutoff value were included in FNA + SWE or FNA + SWE + BRAF negative ones, and those whose SWE Emax were greater than the cutoff value were included in positive ones. The diagnostic efficacy of SWE, FNA, SWE + FNA, FNA + BRAF and their combination in ACR TI-RADS 4 and 5 thyroid nodules were compared. The ROC curve showed that the best cutoff value of SWE Emax was 40.9 kpa, and the area under ROC curve (AUC) was 0.842 (0.800∼0.885). The sensitivity, specificity and accuracy of SWE were 76.3% (270/354), 75.5% (80/106) and 76.1% (350/460), respectively. The sensitivity, specificity and accuracy of FNA were 58.2% (206/354), 88.7% (94/106) and 65.2(300/460), respectively. The sensitivity, specificity and accuracy of FNA + BRAF were 95.5% (338/354), 88.7% (94/106) and 93.9% (432/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA were 85.9% (304/354), 98.1% (104/106) and 88.7% (408/460), respectively. The sensitivity, specificity and accuracy of SWE + FNA + BRAF were 98.3% (348/354), 98.1% (104/106) and 98.3% (452/460), respectively. For the diagnostic accuracy, SWE + FNA + BRAF > FNA + BRAF > FNA + SWE > SWE > FNA, the difference was statistically significant (all P > 0.05). For ACR TI-RADS 4 and 5 thyroid nodules, SWE and FNA have high diagnostic efficiency. For the diagnostic accuracy, FNA + BRAF is better than FNA + SWE. FNA combination with BRAF gene detection further improves the diagnostic sensitivity and accuracy of FNA. The combined application of the three is the best.

The Value of High-Resolution Ultrasound Combined with Shear-Wave Elastography under Artificial Intelligence Algorithm in Quantitative Evaluation of Skin Thickness in Localized Scleroderma.

The aim of this study was to explore the value of high-resolution ultrasound combined with shear-wave elastography (SWE) in measuring skin thickness in patients with localized scleroderma (LS). Fifty patients with LS diagnosed by pathology in the hospital were selected as the research object, with a total of 96 lesions. Healthy people (50 cases) in the same period were selected as the control group. The skin thickness of the abdomen, chest, and left finger of the two groups was compared. The traditional nonlocal means (NLM) algorithm was improved by changing the Euclidean distance and introducing a cosine function, which was applied to the ultrasonic imaging intelligent diagnosis of patients with localized scleroderma. SWE imaging was evaluated, and the results demonstrated that LS lesion edema stage accounted for 7.29%, hardening stage occupied 43.75%, and the proportion of atrophy stage reached 48.96%. When the size of shell was 1 mm, maximum elastic modulus (Emax) was 0.984, mean of elastic modulus (Emean) was 0.926, and electro-static discharge (Esd) was 0.965. When the size of shell was 2 mm, the elastic moduli around lesions were as follows: Emax was 0.998, Emean was 0.968, and Esd was 0.997. By comparing the skin thickness of the abdomen, chest, and left finger, it was found that there was a significant difference between the LS group and the control group (P < 0.05). When the shell was 2 mm, the effect of sensitivity specificity on SWE imaging was better than that when the shell was 1 mm. In summary, the improved NLM algorithm showed excellent denoising effects on the ultrasonic images of LS patients. Besides, it could assist clinicians in ultrasonic imaging diagnosis for LS patients and effectively improve the diagnostic accuracy of diseases.

Deep learning based sarcopenia prediction from shear-wave ultrasonographic elastography and gray scale ultrasonography of rectus femoris muscle

We aim to evaluate the performance of a deep convolutional neural network (DCNN) in predicting the presence or absence of sarcopenia using shear-wave elastography (SWE) and gray-scale ultrasonography (GSU) of rectus femoris muscle as an imaging biomarker. This retrospective study included 160 pair sets of GSU and SWE images (n = 160) from December 2018 and July 2019. Two radiologists scored the echogenicity of muscle on GSU (4-point score). Among them, 141 patients underwent CT and their L3 skeletal muscle index (SMI) were measured to categorize the presence or absence of sarcopenia. For DCNN, we used three CNN architectures (VGG19, ResNet-50, DenseNet 121). The accuracies of DCNNs for sarcopenia classification were 70.0–80.0% (based on SWE) and 65.0–75.0% (based on GSU). The DCNN application to SWE images highlights the utility of deep-learning base SWE for sarcopenia prediction. DCNN application to SWE images might be a potentially useful biomarker to predict sarcopenic status.

Feasibility Trial to Evaluate Tendon Stiffness Obtained from Shear Wave Elastography Imaging as a Biomarker of Aromatase Inhibitor-Induced Arthralgias

Aromatase inhibitor-induced arthralgia (AIA) comprises significant, activity-limiting musculoskeletal symptoms, including joint pain, myalgia, and joint stiffness. We conducted a prospective feasibility study in postmenopausal women diagnosed with early-stage (0–3) hormone receptor positive (HR+) breast cancer who were candidates for treatment with adjuvant AI therapy (n = 16). Tendons of the hands and wrists and the median nerve were imaged using gray-scale and power Doppler ultrasound (US) and US SWE. Arthralgia symptoms were evaluated using the Breast Cancer Prevention Trial (BCPT) Symptom Checklist musculoskeletal subscale (MS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and stiffness subscales. At baseline, there were significant differences in the SW velocities of tendons between dominant and nondominant hands. Increased velocity in 2 of 6 tendons and the median nerve was associated with greater pain at baseline, whereas slower velocity of the extensor digitorum tendon (suggesting decreased stiffness) was associated with a higher WOMAC stiffness score. Increased SW velocity (suggestive of increased stiffness) at baseline in the abductor pollicis longus tendon was associated with a worsening of all three pain and stiffness measures by 6 months. Future studies should evaluate SWE scores related to AIA outcomes in a larger sample size.

Fusion of B‐mode and shear wave elastography ultrasound features for automated detection of axillary lymph node metastasis in breast carcinoma

AbstractIn this study, we evaluate and compare the diagnostic performance of ultrasound for non‐invasive axillary lymph node (ALN) metastasis detection. The study was based on fusing shear wave elastography (SWE) and B‐mode ultrasonography (USG) images. These images were subjected to pre‐processing and feature extraction, based on bi‐dimensional empirical mode decomposition and higher order spectra methods. The resulting nonlinear features were ranked according to their p‐value, which was established with Student's t‐test. The ranked features were used to train and test six classification algorithms with 10‐fold cross‐validation. Initially, we considered B‐mode USG images in isolation. A probabilistic neural network (PNN) classifier was able to discriminate positive from negative cases with an accuracy of 74.77% using 15 features. Subsequently, only SWE images were used and as before, the PNN classifier delivered the best result with an accuracy of 87.85% based on 47 features. Finally, we combined SWE and B‐mode USG images. Again, the PNN classifier delivered the best result with an accuracy of 89.72% based on 71 features. These three tests indicate that SWE images contain more diagnostically relevant information when compared with B‐mode USG. Furthermore, there is scope in fusing SWE and B‐mode USG to improve non‐invasive ALN metastasis detection.

Shear wave elastography and shear wave dispersion imaging in primary biliary cholangitis-a pilot study.

Primary biliary cholangitis (PBC) is a chronic liver disease that can lead to liver fibrosis and cirrhosis. Two-dimensional shear wave elastography (2D-SWE) is a modern technique for fibrosis assessment. However, data regarding its performance in PBC is sparse. We aimed to characterize severity of liver disease in PBC patients using non-invasive 2D-SWE and the new methods of attenuation imaging (ATI) and shear wave dispersion imaging (SWD). Twenty two PBC patients were examined with 2D-SWE, SWD and ATI, alongside established non-invasive fibrosis and steatosis assessment methods as well as liver function tests. Median 2D-SWE values were 1.48 m/s (range, 1.14-2.13 m/s) and 6.7 kPa (range, 3.8-14.7 kPa), respectively. Median SWD, ATI, transient elastography (TE) and controlled attenuation parameter (CAP) values were 13.9 m/s/kHz (range, 11.6-21 m/s/kHz), 0.57 dB/cm/MHz (range, 0.5-0.68 dB/cm/MHz), 7 kPa (range, 3.7-14.6 kPa), and 208 dB/m (range, 107-276 dB/m), respectively. 2D-SWE displayed a significant correlation with spleen length, platelet count, non-invasive fibrosis scores (FIB-4, APRI) and with TE. SWD correlated with alkaline phosphatase (ALP) levels, which is a prognostic marker in PBC. Our findings add further evidence that 2D-SWE is a reliable method for fibrosis assessment in PBC. Even though the cohort size was small, the correlation of SWD with the prognostic marker ALP suggests a potentially valuable role of this new non-invasive method in evaluating liver disease activity in PBC.

Cost-Effectiveness of Prostate Cancer Detection in Biopsy-Naïve Men: Ultrasound Shear Wave Elastography vs. Multiparametric Diagnostic Magnetic Resonance Imaging.

This exploratory study investigates the cost-effectiveness of ultrasound shear wave elastography (SWE) imaging in comparison to pre-biopsy multiparametric magnetic resonance imaging (mpMRI) in men with suspected prostate cancer. This research is motivated by the early evidence of the good performance of SWE in distinguishing cancerous from benign prostate tissues. We used a decision analysis model representing the care-pathways of men referred with a high prostate specific antigen (PSA) and/or abnormal digital rectal examination (DRE) in a UK setting from the payer’s perspective with results reported in 2016 GBP. We then appraised the cost-effectiveness of a novel approach based on SWE compared to the more conventional and widely practiced mpMRI-based approaches using data reported in the literature. Deterministic and probabilistic sensitivity analyses were used to address uncertainty regarding the parameter values utilised. Our exploratory results implied that SWE approach yielded an additional quality-adjusted life year (QALY) at the cost of GBP 10,048 compared to the standard mpMRI-based approach in the UK. This is lower than the official willingness to pay threshold of GBP 20,000 (the UK healthcare system guidelines) and is therefore a suitable replacement for the current practice. Sensitivity analyses confirmed the robustness of our results.

Feasibility of Shear Wave Elastography Imaging for Evaluating the Biological Behavior of Breast Cancer.

ObjectiveTo explore the feasibility of shear wave elastography (SWE) parameters for assessing the biological behavior of breast cancer.Materials and MethodsIn this prospective study, 224 breast cancer lesions in 216 female patients were examined by B-mode ultrasound and shear wave elastography in sequence. The maximum size (Smax) of the lesion was measured by B-mode ultrasound, and then shear wave elastography was performed on this section to obtain relevant parameters, including maximum elasticity (Emax), mean elasticity (Emean), standard deviation of elasticity (SD), and the area ratio of shear wave elastography to B-mode ultrasound (AR). The relationship between SWE parameters and pathological type, histopathological classification, histological grade, lymphovascular invasion status (LVI), axillary lymph node status (ALN), and immunohistochemistry of breast cancer lesions was performed according to postoperative pathology.ResultsIn the univariate analysis, the pathological type and histopathological classification of breast cancer were not significantly associated with SWE parameters; with an increase in the histological grade of invasive ductal carcinoma (IDC), SD (p = 0.016) and Smax (p = 0.000) values increased. In the ALN-positive group, Smax (p = 0.004) was significantly greater than in the ALN-negative group; Smax (p = 0.003), Emax (p = 0.034), and SD (p = 0.045) were significantly higher in the LVI-positive group than in the LVI-negative group; SD (p = 0.043, p = 0.047) and Smax (p = 0.000, p = 0.000) were significantly lower in the ER+ and PR+ groups than in the ER- and PR- groups, respectively; AR (p = 0.032) was significantly higher in the ER+ groups than in the ER- groups, and Smax (p = 0.002) of the HER2+ group showed higher values than that of the HER2- group; Smax (p = 0.000), SD (p = 0.006), and Emax (p = 0.004) of the Ki-67 high-expression group showed significantly higher values than those of the Ki-67 low-expression group. In the multivariate analysis, Ki-67 was an independent factor of Smax (p = 0.005), Emax (p = 0.004), and SD (p = 0.006); ER was an independent influencing factor of Smax (p = 0.000) and AR (p = 0.032). LVI independently influences Smax (p = 0.006).ConclusionsThe SWE parameters Emax, SD, and AR can be used to evaluate the biological behavior of breast cancer.

Ultrasound shear wave elastography imaging of common carotid arteries in patients with Spontaneous Coronary Artery Dissection (SCAD)

BackgroundShear wave elastography (SWE) is emerging as a valuable clinical tool for a variety of conditions. The aim of this pilot study was to assess the potential of SWE imaging of the common carotid arteries (CCA) in patients with spontaneous coronary artery dissection (SCAD), a rare but potentially life-threatening condition, hypothesized to be linked to changes in vessel wall elasticity.MethodsUltrasound shear wave elastography (SWE) estimates of artery wall elasticity were obtained from the left and right CCAs of 89 confirmed SCAD patients and 38 non-dissection controls. SWE images obtained over multiple cardiac cycles were analysed by a blinded observer to estimate elasticity in the form of a Young’s Modulus (YM) value, across regions of interest (ROI) located within the anterior and posterior CCA walls.ResultsYM estimates ranged from 17 to 133 kPa in SCAD patients compared to 34 to 87 kPa in non-dissection controls. The mean YM of 55 [standard deviation (SD): 21] kPa in SCAD patients was not significantly different to the mean of 57 [SD: 12] kPa in controls, p = 0.32. The difference between groups was 2 kPa [95% Confidence Interval − 11, 4].ConclusionsSWE imaging of CCAs in SCAD patients is feasible although the clinical benefit is limited by relatively high variability of YM values which may have contributed to our finding of no significant difference between SCAD patients and non-dissection controls.