Ultrasonic Elastography Research Articles

Preliminary Exploration on the Value of Shear Wave Elastography in Evaluating the Effectiveness of Microwave Ablation on Hepatic Malignancies.

Shear wave elastography (SWE) is a new type of ultrasonic elastography that can quantitatively assess the elasticity and stiffness of tissues. This study aimed to investigate the value of SWE in evaluating the effectiveness of microwave ablation in hepatic malignancies. A total of 24 patients (including 30 lesions) with liver malignancies receiving microwave ablation treatment at the Cancer Hospital of Guangzhou Medical University from April 2018 to January 2019 were enrolled. The elastography was performed within 1 week before and after ablation. The SWE values in the central zone, the marginal zone of the lesion, and peripheral liver parenchyma were collected and analyzed. Before ablation, the mean of SWE value was 65.80 ± 13.37 kPa for the central zone of the tumor and 39.93 ± 7.87 kPa for the marginal zone, both of which were significantly greater than that for the perinatal liver parenchyma (12.85 ± 2.67 kPa, both P < 0.05). In the central and marginal zone of the lesions, the SWE value was significantly elevated after ablation (both P < 0.001) but not in the peripheral liver parenchyma (P = 0.444). Receiver operating characteristic curve analysis showed that the cutoff value for ablation in the marginal zone was 53.87 kPa, suggesting that an SWE exceeding 53.87 kPa is an index guaranteeing the ablation effectiveness. These results suggested that SWE has the potential to be used in evaluating the effectiveness of microwave ablation in liver cancers.

Reliability of shear wave elastography for the assessment of gastrocnemius fascia elasticity in healthy individual

The mechanical properties of the deep fascia, particularly their stiffness, strongly affect the development of muscle pathologies (such as compartment syndrome) and the action of the muscles. However, the mechanical characteristics of the deep muscular fascia are still not clearly understood. The present study focuses on examining the reliability of ultrasonic shear wave elastography (USWE) devices in quantifying the shear modulus of the gastrocnemius fascia in healthy individuals, particularly their ability to measure the shear modulus of the deep fascia of the gastrocnemius during ankle dorsiflexion. Twenty-one healthy males (age: 21.48 ± 1.17 years) participated in the study. Using USWE, the shear moduli of the medial gastrocnemius fascia (MGF) and lateral gastrocnemius fascia (LGF) were quantified at different angles during passive lengthening. The two operators took turns measuring each subject’s MGF and LGF over a 1-h period, and operator B took an additional measurement 2 h later. For the intra-operator test, the same subjects were measured again at the same time of day 5 days later. Both the intrarater [intraclass correlation coefficient (ICC) = 0.846–0.965)] and interrater (ICC = 0.877–0.961) reliability values for measuring the shear moduli of the MGF and LGF were rated as excellent; the standard error of the mean (SEM) was 3.49 kPa, and the minimal detectable change (MDC) was 9.68 kPa. Regardless of the ankle angle, the shear moduli of the LGF were significantly greater than that of the MGF (p < 0.001). Significant increases in the shear moduli of both the MGF and the LGF were observed in the neutral position compared to the relaxed position. These results indicate that USWE is a reliable technique to assess the shear modulus of the gastrocnemius fascia and detect its dynamic changes during ankle dorsiflexion. USWE can be used for biomechanical studies and intervention experiments concerning the deep fascia.

The effect of a shoe lift on tensor fasciae latae length during standing with an artificial functional leg length discrepancy: An ultrasonic shear wave elastography study.

Shortening of tensor fasciae latae is one factor that causes a functional leg length discrepancy. A shoe lift has been used to correct the compensatory posture resulting from the discrepancy. Despite the potential therapeutic benefit of a shoe lift, the mechanism by which it exerts its effect is unclear. To investigate the effect of a shoe lift on tensor fasciae latae length during standing with an artificial functional leg length discrepancy using ultrasonic shear wave elastography. Twenty-two healthy individuals performed static standing under three conditions: drop of the pelvis and flexion of the leg resulting from fixing in the hip abduction position using a hip orthosis (functional leg length discrepancy condition); drop of the pelvis by the orthosis, but no flexion of the leg due to a shoe lift (shoe lift condition); and normal bilateral standing condition. The shear elastic modulus of tensor fasciae latae was calculated using ultrasonic shear wave elastography. The shear elastic modulus was significantly lower in the functional leg length discrepancy condition than in the shoe lift and normal conditions (p= 0.038). Using a shoe lift for the functional leg length discrepancy can result in a functional hip position that elongates tensor fasciae latae.

Proposing ultrasonic elastography as new evaluation method for erectile function

ABSTRACT Introduction For diagnosing vasculogenic erectile dysfunction (ED), the prostaglandin E1 intracavernous injection test (PGE1 test) is an established method. However, its evaluation is often influenced by the subjectivity of the evaluator. Objective We objectively evaluated the changes in the corpus cavernosum before and after injection using percutaneous ultrasonic elastography in patients undergoing the PGE1 test. Methods We measured and evaluated the shear wave velocity in the corpus cavernosum by ultrasonic elastography (Canon Medical Systems Co., Ltd. Aplio i800) before and after injection, by a single doctor, in 16 patients who underwent the PGE1 test at our hospital, between April 2020 and March 2021. Results The response score of PGE1 tests were "1" in 2 cases, "2" in 2 cases, "3" in 12 cases, while "0" and "4" were not observed. The average transmission velocity before injection was 2.21m/s, and the average transmission velocity at the time of maximum erection after injection was 1.57m/s. In 14 of 16 cases (87.5%), the transmission velocity decreased during erection. The rate of change in transmission velocity due to injection was minus 26.7% overall, and was significantly different between the poor erection group (response 1 and 2: minus 16.1%) and the good erection group (response 3: minus 30.2%). Conclusions To our knowledge, this is the first report of an attempt to evaluate erectile phenomenon by ultrasonic elastography. The rate of change in the shear wave transmission velocity due to PGE1 test in the penile corpus cavernosum was associated with the degree of erection. It was suggested that the rate of change in shear wave transmission velocity in the penile corpus cavernosum could be used as an objective index of erectile phenomenon. Ultrasonic elastography is a non-invasive test method; therefore, it will be useful for patients if this method becomes established for diagnosing ED, determining the therapeutic effect, and predicting the prognosis. Disclosure Work supported by industry: no.

CARDIOHEPATIC SYNDROME: INNOVATIVE DIAGNOSTICS BY ULTRASOUND ELASTOGRAPHY

The purpose of this work is to study the aspects of cardiohepatic syndrome at the present stage of medicine development, as well as the diagnostic opportunities of ultrasound elastography in its assessment. The methods of statistical analysis, generalization, comparison and systematization of data were used. The article describes in detail the current state of cardiohepatic syndrome problem. To date, the cardiohepatic syndrome, along with the well-studied cardiorenal one, is becoming more and more relevant, as it reflects the hepatotrophic effect of pathogenetic chronic heart failure factors on the liver tissue. The cardiohepatic syndrome in a broad sense is the presence of simultaneous liver and heart dysfunctions in the development of various nosologies. However, most often this symptom complex is described in the literature in a narrower sense – as a consequence of organ damage to the liver due to the development of acute and chronic heart failure. The main pathogenetic mechanism of cardiac hepatopathies is liver fibrosis. The prognosis of the disease and the life of patients depends on liver fibrosis advance. And early diagnosis of pre-existing fibrosis will make it possible to suspend the process of fibrotic scarring that has begun and its further transformation into cardiac liver cirrhosis. To date, the "gold standard" of fibrosis instrumental diagnosis is a liver biopsy, but due to restrictions and contraindications, the method is limited in its use. Ultrasound elastography is the main non-invasive method for diagnosing fibrosis. At the present stage of expanded diagnostic opportunities, several methods of ultrasonic elastography are described: strain elastography, point shear wave elastography (ARFI-elastometry), indirect transient elastography, two-dimensional shear wave elastography. The experience of using ultrasound elastography is described in the diagnosis of diffuse liver diseases – hepatitises, non-alcoholic fatty liver disease. As part of the cardiohepatic syndrome studying, the technique is innovative and requires further study.

Differential diagnosis of basal cell carcinoma by high-resolution ultrasound elastography.

The aim of this study was to assess the value of high-resolution ultrasonic quantitative parameters of shear wave elastography (SWE) in basal cell carcinoma (BCC). A total of 86 cases of BCC were enrolled as the case group, and 38 other similar skin pigmented lesions were randomly selected as the control group. Using pathological results as the gold standard, the diagnostic test method was used to evaluate the ability of high-frequency ultrasonic elastography to diagnose BCC, and the 2D ultrasonographic features, blood flow image characteristics, and SWE of BCC were summarized.

Ultrasonic Elastography of the Rectus Femoris, a Potential Tool to Predict Sarcopenia in Patients With Chronic Obstructive Pulmonary Disease.

Purpose: Skeletal muscle dysfunction is common in patients with chronic obstructive pulmonary disease (COPD) and is associated with a poor prognosis. Abnormal muscle quantity of the lower limbs is a manifestation of skeletal muscle dysfunction in patients with COPD. Shear wave ultrasound elastography (SWE) is a novel and possible tool to evaluate qualitative muscle parameters. This study explores the feasibility of SWE to measure the stiffness of the rectus femoris and evaluates its value in predicting sarcopenia in patients with COPD.Methods: Ultrasound examination of the rectus femoris was performed to determine the mean elasticity index (SWEmean), cross-sectional area (RFcsa), and thickness (RFthick) using grayscale ultrasonography (US) and SWE in 53 patients with COPD and 23 age-matched non-COPD healthy controls. The serum levels of circulating biomarkers (GDF15, resistin, and TNF-α) were measured using ELISA. The definition of sarcopenia followed the guidelines from the Asian Working Group for Sarcopenia. Receiver operating characteristic (ROC) curve analysis of the SWEmean, RFthick, and RFcsa was used to evaluate their predictive ability for sarcopenia.Results: The intraobserver and interobserver repeatability of SWE performance was excellent (all correlation coefficients > 0.95; p < 0.05). The SWEmean of the rectus femoris in patients with COPD (8.98 ± 3.12 kPa) was decreased compared with that in healthy controls (17.00 ± 5.14 kPa) and decreased with advanced global initiative for chronic obstructive lung disease (GOLD) stage. Furthermore, SWEmean was found to be independent of sex, height, and body mass, and a lower SWEmean in patients with COPD was positively associated with reduced pulmonary function, worse physical function, poor exercise tolerance, decreased muscle strength, and worse dyspnea index score. The correlation between physical function [five-repetition sit-to-stand test (5STST)], muscle function, and SWEmean was higher than those of RFthick and RFcsa. In addition, SWEmean was negatively correlated with serum GDF15 levels (r = −0.472, p < 0.001), serum resistin levels (r = −0.291, p = 0.035), and serum TNF-α levels (r = −0.433, p = 0.001). Finally, the predictive power of SWEmean [area under the curve (AUC): 0.863] in the diagnosis of sarcopenia was higher than that of RFthick (AUC: 0.802) and RFcsa (AUC: 0.816).Conclusion: Compared with grayscale US, SWE was not affected by the patient’s height, weight, or BMI and better represented skeletal muscle function and physical function. Furthermore, SWE is a promising potential tool to predict sarcopenia in patients with COPD.

Study on the Value of Ultrasound Elastography Combined with Plasma miRNA Expression in the Early Detection of Breast Cancer

Background: Breast cancer (BC) is the most common malignant tumor in women, and its morbidity and mortality are increasing each year, due to the lack of specific clinical symptoms in the early stage of BC, and the lack of diagnostic methods for early breast cancer. Therefore, identifying an effective diagnostic method for early BC has become urgent. Materials and Methods: Breast lesions with a histological diagnosis that were examined by ultrasonic elastography (UE) in our department from June 2020 to December 2021 were reviewed. qRT-PCR was performed to measure the expression levels of miR-144-5p and miR-26b-5p in the plasma of patients with BC. The receiver operating characteristics (ROC) curve and area under the curve (AUC) were used to investigate the potential diagnostic value of miR- 144-5p, miR-26b-5p and the elastographic score in BC. Results: The ultrasonic elastography score(UES) was found to be significantly upregulated in BC compared with that in benign breast lesions, and the AUC, sensitivity and specificity were 0.809, 0.717 and 0.806 for distinguishing BC from benign breast lesions, respectively. miR-144-5p and miR-26b- 5p were found to be upregulated in the plasma of BC patients, and miR-144-5p+miR-26b-5p had 0.781 sensitivity and 0.780 specificity for the diagnosis of BC. Furthermore, we found that the diagnostic performance of miR-144-5p and miR-26b-5p combined with UES for BC had 0.913 sensitivity and 0.890 specificity. Conclusions: The combination of plasma miR-144-5p, miR-26b-5p and UES has a very high clinical application value for the early detection of BC.

Ultrasonic elastography for nondestructive evaluation of dissimilar material joints

Dissimilar material joints or multilayered metals have become inevitable in the manufacturing industry due to the increasing demand for multifunctional materials with variable mechanical, thermal, or electrical characteristics in a single assembly. Lattice mismatch of materials at the interface of dissimilar materials leads to inferior mechanical characteristics. In particular, the mismatch in elastic properties indicated by a large initial elastic deformation is critical to determine the extent of variation in stress. However, nanoindentation, the most common and accepted technique to measure elastic modulus, is destructive, time-consuming, and can only examine mechanical properties within a limited area. A non-invasive elastographic mapping technique evaluates the mechanical properties using ultrasonic elastography to study incompressibility. The dissimilar joint between steel and copper was obtained via friction stir welding. The variation of the stress developed at the welded joint of the two different metals was evaluated from the dynamic bulk modulus map. A tensile test of the involved workpiece confirmed a good agreement with our analysis based on the dynamic bulk modulus elastographic mapping results. This study provides a rapid and non-invasive technique for the bulk metallurgic elastic modulus inspection to overcome the limitations of conventional methods.

Does ultrasonic elastography show high sensitivity in diagnosing benign and malignant thyroid nodules?

Does ultrasonic elastography show high sensitivity in diagnosing benign and malignant thyroid nodules?

The Value of Ultrasonic Elastography Combined With Serum ATF5 in Predicting the Efficacy of Neo-adjuvant Chemotherapy in Breast Cancer: Erratum.

The Value of Ultrasonic Elastography Combined With Serum ATF5 in Predicting the Efficacy of Neo-adjuvant Chemotherapy in Breast Cancer: Erratum.

Diagnostic Performance of Strain and Shear Wave Elastography for the Response to Neoadjuvant Chemotherapy in Breast Cancer Patients: Systematic Review and Meta-Analysis.

To investigate the diagnostic performance of strain and shear wave elastography for the response to neoadjuvant chemotherapy (NAC) in breast cancer patients. Relevant studies were searched in the databases of PubMed, Web of Science and Cochrane Library until October 2021. The diagnostic performance of ultrasonic elastography for the response to NAC were estimated by calculating the area under the curve (AUC) with sensitivity and specificity using Stata 14.0. A total of 15 studies that comprise 1147 breast cancer patients were included in this meta-analysis. The pooled AUC of strain elastography in diagnosing responses were 0.89 (95% CI=0.86-0.91) with 87% (95% CI=75-94%) of sensitivity and 80% (95% CI=72-84%) of specificity. The pooled AUC of shear wave elastography in diagnosing response were 0.82 (95% CI=0.78-0.85) with 79% (95% CI=72-84%) of sensitivity and 81% (95% CI=71-88%). No publication bias was observed across the studies using Deek's funnel plot. Based on current evidence, this meta-analysis confirmed that strain and shear wave elastography exhibited favorable performance for predicting responses to NAC. Strain and shear wave elastography may be a useful, noninvasive method for the assessment of response to NAC in breast cancer patients.

Ultrasonic Elastography Combined with Human Papilloma Virus Detection Based on Intelligent Denoising Algorithm in Diagnosis of Cervical Intraepithelial Neoplasia.

The aim of this research was to study the application of ultrasonic elastography combined with human papilloma virus (HPV) detection based on bilateral filter intelligent denoising algorithm in the diagnosis of cervical intraepithelial neoplasia (CIN) and provide a theoretical basis for clinical diagnosis and treatment of CIN. In this study, 100 patients with cervical lesions were selected as research objects and randomly divided into control group and experimental group, with 50 cases in each group. Patients in control group and experimental group were diagnosed by ultrasonic elastography combined with HPV detection. The experimental group used the optimized image map of bilateral filter intelligent denoising algorithm for denoising and optimization, while the control group did not use optimization, and the differences between them were analyzed and compared. The diagnostic effects of the two groups were compared. As a result, the three accuracy rates of the experimental group were 95%, 95%, and 98%, respectively; the three sensitivity rates were 96%, 92%, and 94%, respectively; and the three specificity rates were 99%, 97%, and 98%, respectively. In the control group, the three accuracy rates were 84%, 86%, and 84%, respectively; the three sensitivity rates were 88%, 84%, and 86%, respectively; and the three specificity rates were 81%, 83%, and 88%, respectively. The accuracy, sensitivity, and specificity of experiment group were significantly higher than those of control group, and the difference was statistically significant (P < 0.05). In summary, the bilateral filter intelligent denoising algorithm has a good denoising effect on the ultrasonic elastography. The ultrasonic image processed by the algorithm combined with HPV detection has a better diagnosis of CIN.

An Innovative Approach to Studying the State of the Uterine Scar after Cesarean Section on the Basis of a Comparative Study

Background. Today we have not really highly informative methods for assessing the state of the uterine scar. This fact does not allow us to formulate clear selection criteria for spontaneous delivery for patients who had cesarean section (CS). The result of the formulated problem is not only an increase in the frequency of repeated abdominal delivery, but also a fivefold increase in the risks of intraoperative and postoperative complications for women of reproductive age. Aims explore the property, structure and morphological features of the myometrial scar tissue by developing a physical model based on morphological predictors. Materials and methods. The study included 49 women who ahead a second caesarean section in the maternity hospital at the S.S. Yudin state medical center. The patients had scar tissue excised in the lower uterine segment and the resulting biopsies were divided into 2 fragments. The first fragment of biopsies was necessary for performing a morphological study, based on the results of which randomization was carried out into groups. The main group included 24 fragments, where the scar tissue was well-established, and the comparison group included 25 fragments, where according to morphological research, signs of its insolvency were revealed. Further assessment of the scar state was performed using the second fragment of biopsies by creating a physical model of the study, on the basis of which the dependence of elongation on the applied force was estimated. The study was conducted in the laboratory of scientific research on the development of bioprostheses of the CSSC A.N. Bakuleva. Results. Based on a morphological study, it was confirmed that the failure of the scar is based on the disorganization of connective tissue, indicating the possible presence of undifferentiated connective tissue dysplasia for the patient. The physical model of the study demonstrated that the presence of such a difficult-to-diagnose pathology leads to a decrease in the elasticity, and therefore-the strength and elasticity of the scar on the uterus. Conclusions. For this period of time, we need to improve methods for assessing the condition of the uterine scar in order to resolve the issue of the possibility of conducting natural childbirth for patients after undergoing CS surgery. It is possible that the created physical model will be able to evaluate the predictive ability of ultrasonic elastography within the framework of this problem. It is important to remember that scar formation is the final stage of regeneration, therefore, the maximum number of answers to a detailed study of morphological and immunohistochemical features of the myometrium, as it is the primary matrix on which will be the formation of scar tissue.

Efficacy of logistic regression model based on multiparametric ultrasound in assessment of cervical lymphadenopathy - a retrospective study.

To investigate whether a multiparametric ultrasound (MPUS) diagnostic model improves differential diagnosis of benign and malignant cervical lymph nodes. MPUS evaluation was performed on 87 lesions in 86 patients, and related characteristics and parameters of the patients and lesions were studied and logistic regression models based on the MPUS characteristics of cervical lymph nodes were built. A receiver operating characteristic curve and area under the curve (AUC) were built for the evaluation of diagnostic performances. Of the 87 lesions in 86 patients, there were 31 benign and 56 malignant lesions. Regression models for Duplex ultrasound and MPUS were established. The Duplex ultrasound regression model showed a sensitivity, specificity, positive predictive value and negative predictive value of 94.4, 61.3, 86.3 and 80.9%, respectively. The predictive accuracy was 82.4%, and the AUC was 0.861. The MPUS regression model showed a sensitivity, specificity, positive predictive value and negative predictive value of 98.1, 61.3, 81.5 and 95.0%, respectively. The predictive accuracy was 84.7%, and the AUC was 0.894. The differences in AUCs between the Duplex ultrasound model and MPUS model, ultrasound model and ultrasonic elastography (UE), and Duplex ultrasound and UE were not significant (all p > 0.05); the differences in AUCs between the MPUS model and Duplex ultrasound, Duplex ultrasound model and Duplex ultrasound, and MPUS model and UE were significant (all p < 0.05). The Duplex ultrasound and MPUS models achieve significantly higher diagnostic performance for differentiating between benign and malignant cervical lymph nodes.

Effects of hot pack application before high-intensity stretching on the quadriceps muscle

Background/aims High-intensity static stretching is assumed to increase the range of motion and/or decrease muscle stiffness; however, the effects of high-intensity static stretching on the quadriceps muscle have been debated. Hot pack application before high-intensity static stretching was assumed to decrease stretching pain, which is the main problem in high-intensity static stretching, and decrease quadriceps muscle stiffness. This study aimed to examine hot pack application before high-intensity static stretching on stretching pain, knee flexion range of motion, and quadriceps muscle stiffness. Methods In total, 21 healthy sedentary male participants randomly performed two interventions: high-intensity static stretching and hot pack application before stretching. Static stretching was performed at three 60-second stretching interventions with a 30-second interval. Then, a 20-minute hot pack was applied before high-intensity static stretching. The knee flexion range of motion and shear elastic modulus of the quadriceps muscle were measured by ultrasonic shear-wave elastography before and after the static stretching intervention. Results Stretching pain after hot pack application before stretching was lower than high-intensity static stretching alone. Significant increases were also found in knee flexion range of motion after both stretching interventions, but no significant difference was noted in the increase in the knee flexion range of motion with or without hot pack application. No significant change was found in quadriceps muscle stiffness in either intervention. Conclusions The results suggest that hot pack application before high-intensity static stretching could decrease stretching pain, but no significant difference in knee flexion range of motion increase was found.

Role of Ultrasonic Elastography in the Evaluation of Fibrosis in Children with Chronic Liver Disease in Comparison to Liver Biopsy

Background: Chronic liver illnesses can be caused by a variety of factors, including metabolic, genetic, drug-induced, inflammatory, structural, dietary, and immunological factors. Even with Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI), liver fibrosis makes diagnostic imaging difficult in chronic liver injury. Percutaneous liver biopsy is the gold standard for diagnosing, grading, and monitoring liver fibrosis in children, but it is painful, invasive, requires heavy sedation, and has numerous complications such as bleeding. Objectives: The aim of the current work was to assess and measure liver stiffness in children with chronic liver disease using real-time elastography (RTE), compare the results to histopathological findings obtained after performing a percutaneous liver biopsy, and investigate the availability of noninvasive safe liver elastography as a future replacement for this invasive tool in the evaluation and grading of liver fibrosis. Patients and methods: This hospital-based cross-sectional comparative study included a total of 30 individuals with chronic liver disease of various etiologies with age ranged from 4-16 years, attending at Department of Pediatric, Sohag University Hospitals. This study was conducted between January 2017 to December 2019. A control group of ten healthy people was also included in the investigation. Results: The degree of liver stiffness measured by the last ultrasonic elastography was greater in the patient group than in the control group, with a statistically significant difference between the two groups. Except for F0-F1 and F3-F4, there was a substantial relationship between fibrosis stage and liver stiffness assessment by sonoelastography, where the difference was significant between every two individual groups. There was a strong link between biopsy diagnosis and liver stiffness measurement. Conclusion: It could be concluded that in adults, ultrasonic elastography is a well-established approach for assessing liver fibrosis. The utility of elastography in the follow-up of children with chronic liver disease might be increased.

New radiation techniques in controlling bone regeneration in fractures

Objective: comparative study of the possibilities of radiation methods in control of bone regeneration in fractures.Materials and methods. A study of bone calluse formation was conducted in 116 patients with broken tubular bones of the upper and lower limbs from the first day of the fracture to the complete consolidation of the fractures. In X-rays and CT determined the mineral density of bone calluses, with ultrasonic elastography shear wave and compression elastography determined the rigidity of bone calluses in kPa.Results. X-ray bone corn was determined at the end of the second – the beginning of the third stage of bone calluse formation. On CT bone corn density (in the HU), its structure and the condition of bone breaks were determined in some patients in all stages of bone regenerate formation. In ultrasound examination in the multiparametric mode studied the rigidity, structure and vascularization of bone calluses, the correct comparison of bone breaks from the first day of the fracture to their complete fusion.Conclusions. Ultrasonic studies in multiparametric mode can be used to control bone regeneration in fractures. Ultrasonic elastography shear wave, in determining the rigidity of bone calluse, in sensitivity and specificity exceeds the indicators of ultrasonic compression elastography at all stages of bone regenerate formation.

Systematic review and meta-analysis of ultrasonic elastography in the diagnosis of benign and malignant thyroid nodules.

In recent years, ultrasound elastography (USE) has been the main diagnostic technique for benign and malignant thyroid nodules. However, it cannot display the blood flow signals of nodules with smaller diameters clearly, which decreases its diagnostic accuracy. Chinese and English databases were searched using "ultrasonic elastography", "benign and malignant thyroid nodules", and "diagnose" as the search terms. RevMan 5.3 software was used for meta-analysis. A total of 11 randomized controlled trials (RCTs) were included. Eight articles analyzed clinical symptoms, and the heterogeneity test results were Chi2 =7.46, df=7, I2=6%, and P=0.38; and Z=11.44, OR =14.58, 95% confidential interval (CI): 9.21-23.07, and P<0.01. The diagnostic efficacy of USE was analyzed in 8 articles, and the heterogeneity test results were Chi2 =3.03, df=7, I2=0%, and P=0.88; and Z=6.33, OR =7.47, 95% CI: 4.01-13.93, and P<0.01. The pathological diagnosis results of randomized controlled trials were analyzed in 10 literatures, and the heterogeneity test results were Tau2 =0.78, Chi2 =20.97, df=9, I2=57%, and P=0.01; and Z=7.27, OR =14.67, 95% CI: 7.11-30.27, and P<0.01. After meta-analysis, the combined sensitivity was 72.26% (95% CI: 0.625-0.764) and the combined specificity was 95.35% (95% CI: 0.815-0.943). The area under the receiver operating characteristic curve (AUC) was 0.857. This meta-analysis confirmed that USE shows high sensitivity and specificity in diagnosing benign and malignant thyroid nodules, which could reduce the false negative rate (FNR) and false positive rate (FPR), showing high clinical diagnostic value.

Machine Learning in Model-free Mechanical Property Imaging: Novel Integration of Physics With the Constrained Optimization Process

The Autoprogressive Method (AutoP) is a fundamentally different approach to solving the inverse problem in quasi-static ultrasonic elastography (QUSE). By exploiting the nonlinear adaptability of artificial neural networks and physical constraints imposed through finite element analysis, AutoP is able to build patient specific soft-computational material models from a relatively sparse set of force-displacement measurement data. Physics-guided, data-driven models offer a new path to the discovery of mechanical properties most effective for diagnostic imaging. AutoP was originally applied to modeling mechanical properties of materials in geotechnical and civil engineering applications. The method was later adapted to reconstructing maps of linear-elastic material properties for cancer imaging applications. Previous articles describing AutoP focused on high-level concepts to explain the mechanisms driving the training process. In this review, we focus on AutoP as applied to QUSE to present a more thorough explanation of the ways in which the method fundamentally differs from classic model-based and other machine learning approaches. We build intuition for the method through analogy to conventional optimization methods and explore how maps of stresses and strains are extracted from force-displacement measurements in a model-free way. In addition, we discuss a physics-based regularization term unique to AutoP that illuminates the comparison to typical optimization procedures. The insights gained from our hybrid inverse method will hopefully inspire others to explore combinations of rigorous mathematical techniques and conservation principles with the power of machine learning to solve difficult inverse problems.