Muscle belly ratio is the most suitable estimate of the activity of the torn supraspinatus muscle.

Background: A torn rotator cuff muscle deteriorates over time leading with an increase in muscle atrophy and fatty infiltration. There are several clinical assessments for evaluating the atrophy of the torn supraspinatus muscle. However, it is unclear which approach can more accurately estimate the activity of the torn supraspinatus muscle. The purpose of this study was to determine which magnetic resonance imaging-based muscle atrophy imaging assessment currently implemented in the clinical setting accurately estimates the activity of the torn supraspinatus muscle. Methods: Forty patients who were diagnosed with a rotator cuff tear and were candidates for repairs were selected for this study. Cross-sectional area, occupation ratio, and tangent sign were analyzed on T1-weighted oblique sagittal plane magnetic resonance images in which the scapular spine leads to the Y-section. Muscle belly ratio of the supraspinatus muscle was analyzed by calculating the ratio of the width of the muscle belly to the distance from the greater tubercle to the proximal end of the muscle on T1-weighted coronal plane magnetic resonance imaging images. Fatty infiltration was evaluated using the Goutallier classification system. Tear size was obtained intraoperatively by measuring the width and length of the tear and classified based on the Cofield's classification. To assess activity of the torn supraspinatus muscle, participants were first instructed to sit on a chair with the affected arm resting on a table and the shoulder abducted to 60° in the scapular plane with neutral rotation. Elasticity of the supraspinatus muscle belly was then obtained at rest and during isometric contraction using with real-time tissue elastography. Muscle activity, a surrogate for contractility, was defined as the difference between the elasticities measured at rest and during isometric contraction. A stepwise multiple regression analysis was used to investigate independent factors, such as sex, tear width, cross-sectional area, occupation ratio, tangent sign, and muscle belly ratio, related to muscle activity. Results: Stepwise multiple regression analysis (R2 = 0.522, P < .001) revealed that supraspinatus muscle activity was significantly correlated with muscle belly ratio (ß = 0.306, P = .044) and Goutallier stage (ß = -0.490, P = .002). Conclusion: Estimations of muscle belly ratio are most suitable for assessing the activity of a torn supraspinatus muscle compared to other clinical measurements.

A Review about C-TIRADS, ACR-TIRADS, and K-TIRADS Combined with Real-Time Tissue Elastography to Diagnose Thyroid Nodules.

PURPOSE: This study aimed to evaluate the diagnostic efficiency of the Chinese version of thyroid imaging reporting and data system (C-TIRADS), American College of Radiology (ACR)-TIRADS, and Korean (K)-TIRADS combined with real-time tissue elastography to diagnose thyroid nodules. METHODS: A total of 574 thyroid nodule ultrasonographic images were retrospectively analyzed and classified based on the three TIRADS methods. The MedCale statistical software was used to construct the receiver operating characteristic (ROC) curve based on the pathological results of surgery. The diagnostic efficiency before and after assessing elastographies from the three TIRADS was compared between C-TIRADS, ACR-TIRADS, and K-TIRADS groups and within before and after TIRADS combined with elastic imaging. Furthermore, the unnecessary biopsy rates were also compared. Comparing area under ROC curve (AUC) with MEDCALC software (20.0.15, MedCalc Software Ltd., Ostend, Belgium), Delong test was used. The sensitivity and specificity were compared by STATA software (15.1, StataCorp LP, College Station, TX, USA) and Chi-square test. The rate of unnecessary biopsy was compared by SPSS software (23.0, IBM, Armonk, NY, USA) and Chi-square test. RESULTS: C-TIRADS, ACR-TIRADS, K-TIRADS cut-off values, and real-time tissue elastography (RTE) were 4b, 5, 5, and 3, respectively, and the areas under the ROC curve were 0.932, 0.914, 0.904, and 0.883, respectively. C-TIRADS had the highest AUC (p < 0.05) and sensitivity (p < 0.001), while ACR-TIRADS had the highest specificity (p < 0.001). After conducting a combined elastography with the three TIRADS, AUC showed increases of different degrees. Comparing TIRADS with TIRADS+RTE, the difference of C-TIRADS had statistical significance (p < 0.001), but the difference of ACR-TIRADS and K-TIRADS had no statistical significance (p > 0.05). The unnecessary biopsy rate showed decreases of different degrees. Differences between C-TIRADS and K-TIRADS were significant (p < 0.05), but in the case of ACR-TIRADS were not significant (p > 0.05). CONCLUSIONS: C-TIRADS, ACR-TIRADS, K-TIRA and RTE showed high diagnostic efficiency, with C-TIRADS having the highest. Real-time tissue elastography can improve TIRADS diagnostic efficiency and reduce its unnecessary biopsy rate. In this case C-TIRADS showed again the highest efficiency.

Determination of the reference range for semi-quantified elasticity of healthy supraspinatus muscles using real-time tissue elastography and its clinical use in patients after rotator cuff repair.

BACKGROUND: The quantitative assessment of healthy supraspinatus muscle elasticity may provide clinically useful preliminary information after rotator cuff repairs. We aimed to determine the reference range for supraspinatus muscle semi-quantified elasticity and describe how it can be used clinically after rotator cuff repair. METHODS: The elasticity of healthy bilateral supraspinatus muscles in 43 participants aged between 24 and 75 years (categorized into two subgroups: <50 and ≥ 50 years) was measured as a strain ratio at 0° and 60° of shoulder abduction using real-time tissue elastography. The reference and modified reference ranges calculated by excluding outliers for elasticity were determined using normal distribution methods for logarithmically transformed data. The modified reference range was applied to eight cases of rotator cuff repair. FINDINGS: Strain ratios under and over 50 years of age were 1.63 vs. 2.21 at 0° of shoulder abduction (P = 0.028) and 0.92 vs. 1.29 at 60° of shoulder abduction (P = 0.002), respectively. Modified reference ranges for under and over 50 years of age were 0.72-4.17 and 0.98-4.50 at 0° of shoulder abduction and 0.38-1.95 and 0.56-2.76 at 60° of shoulder abduction, respectively. Among eight cases, two showed strain ratios above the reference range at 1 month postoperatively, and rehabilitation protocols were adjusted. INTERPRETATION: A strain ratio above the reference range, especially above the upper limit at 0° of shoulder abduction, may indicate increased passive stiffness of the musculotendinous unit. Clinically, the reference range has the potential to be used as a baseline after rotator cuff repairs.

Comparative Study of Muscle Hardness during Water-Walking and Land-Walking Using Ultrasound Real-Time Tissue Elastography in Healthy Young People.

Compared with land-walking, water-walking is considered to be beneficial as a whole-body exercise because of the characteristics of water (buoyancy, viscosity, hydrostatic pressure, and water temperature). However, there are few reports on the effects of exercise in water on muscles, and there is no standard qualitative assessment method for muscle flexibility. Therefore, we used ultrasound real-time tissue elastography (RTE) to compare muscle hardness after water-walking and land-walking. Participants were 15 healthy young adult males (24.8 ± 2.3 years). The method consisted of land-walking and water-walking for 20 min on separate days. The strain ratio of the rectus femoris (RF) and medial head of gastrocnemius (MHGM) muscles were measured before and immediately after walking using RTE to evaluate muscle hardness. In water-walking, the strain ratio significantly decreased immediately after water-walking, with p < 0.01 for RF and p < 0.05 for MHGM, indicating a significant decrease in muscle hardness after water-walking. On the other hand, land-walking did not produce significant differences in RF and MHGM. Muscle hardness after aerobic exercise, as assessed by RTE, was not changed by land walking but was significantly decreased by water walking. The decrease in muscle hardness induced by water-walking was thought to be caused by the edema reduction effect produced by buoyancy and hydrostatic pressure.

Artificial Intelligence in Hepatology- Ready for the Primetime.

Artificial Intelligence (AI) is a mathematical process of computer mediating designing of algorithms to support human intelligence. AI in hepatology has shown tremendous promise to plan appropriate management and hence improve treatment outcomes. The field of AI is in a very early phase with limited clinical use. AI tools such as machine learning, deep learning, and 'big data' are in a continuous phase of evolution, presently being applied for clinical and basic research. In this review, we have summarized various AI applications in hepatology, the pitfalls and AI's future implications. Different AI models and algorithms are under study using clinical, laboratory, endoscopic and imaging parameters to diagnose and manage liver diseases and mass lesions. AI has helped to reduce human errors and improve treatment protocols. Further research and validation are required for future use of AI in hepatology.

Providing safe and effective rehabilitation by assessing supraspinatus muscle elasticity using ultrasound real-time tissue elastography after rotator cuff repair: A case series.

INTRODUCTION: Although surgical techniques have advanced to avoid a postoperative re-tear after rotator cuff surgery, it remains unclear how to directly evaluate the risk of a re-tear. OBJECTIVE: To describe how muscle elasticity with real-time tissue elastography could be used to avoid re-tear in individual cases after rotator cuff repair. CASE DESCRIPTION: This case series included four patients, two per tear size (small and large/massive), with contrasting changes in muscle elasticity of the supraspinatus muscle. All patients underwent primary arthroscopic or open rotator cuff repair. The elasticity of the supraspinatus muscle was evaluated at relaxed and elongated positions of 0° and 60° shoulder abduction angles, respectively. The change in muscle elasticity at 1 month after surgery was characteristically different, and we predicted that a greater elasticity in the elongated position indicated a higher risk of re-tear. The cases with high risk underwent careful rehabilitation to avoid re-tear, and no re-tears were recorded in this report. CONCLUSION: Our findings suggested that evaluation of muscle elasticity using real-time tissue elastography, which provides an indication of the risk of re-tear, in the clinical setting might be useful for therapists, who could adjust the intensity of rehabilitation, and for patients.

Evaluation of pelvic floor muscle elasticity in patients with overactive bladder syndrome using real-time tissue elastography.

INTRODUCTION AND HYPOTHESIS: The purpose of this study was to compare the muscle elasticity of the striated urethral sphincter (SUS) using real-time tissue elastography (RTE) as an evaluation of pelvic floor muscle (PFM) function between overactive bladder (OAB) patients and healthy women. METHODS: The subjects were 8 healthy middle-aged women (healthy group; age range 57-65 years) and 9 female OAB patients (OAB group; age range 42-80 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The OAB group completed OAB symptom and quality of life questionnaires. The SUS SR was compared between the groups. The SUS SR at rest and during PFM contraction was compared within groups using the t-test and Wilcoxon's test. The relationship between the questionnaire results and the SUS SR was evaluated by correlation analysis. RESULTS: Intergroup comparisons between the healthy and OAB groups showed no significant differences in SUS SR at rest and during PFM contraction. On intragroup comparisons, the SUS SR was significantly higher during PFM contraction than at rest in the healthy group (p = 0.011); in the OAB group, there was no significant difference in the SUS SR between rest and PFM contraction. The SUS SR was not significantly correlated with questionnaire results for OAB symptoms. CONCLUSION: This study shows the potential to non-invasively confirm the inability of OAB patients to correctly perform PFM contraction using RTE.

Combinational elastography for assessment of liver fibrosis in patients with liver injury.

OBJECTIVE: We investigated the utility of combinational elastography with point shear wave elastography (pSWE) and real-time tissue elastography (RTE) for evaluating liver fibrosis in patients with liver injury. METHODS: In this prospective single-institution study, patients scheduled for a liver biopsy to determine the presence of liver disease were enrolled. Liver fibrosis in each patient was evaluated using both shear wave velocity (Vs) shown by pSWE and the liver fibrosis index (LFI) shown by RTE, while a liver biopsy sample was obtained from the same area that was subjected to an elastography examination. Results of the latter were compared with those obtained in a histological examination. RESULTS: Multivariate analysis showed that Vs and LFI were significantly correlated with the liver fibrosis stage in all of the enrolled patients. Sub-analysis findings compared patients with and without non-alcoholic fatty liver disease (NAFLD) and demonstrated that Vs was significantly correlated with the liver fibrosis stage in both groups, whereas LFI was correlated with that only in the non-NAFLD patients. However, a multivariate analysis demonstrated a significant correlation between steatosis grade and LFI in the NAFLD patients. CONCLUSIONS: RTE is less useful than pSWE for assessing liver fibrosis in patients with NAFLD.

Examination of pelvic floor muscle elasticity in patients with interstitial cystitis/bladder pain syndrome using real-time tissue elastography.

INTRODUCTION AND HYPOTHESIS: The aim was to compare pelvic floor muscle (PFM) elasticity between interstitial cystitis/bladder pain syndrome (IC/BPS) patients and healthy women using real-time tissue elastography. METHODS: The subjects were 17 IC/BPS female patients (IC/BPS group; age 34-84 years), 10 healthy middle-aged women (middle-aged group; 50-80 years), and 17 healthy young adult women (young group; 23-37 years). The target sites of elastography were the striated urethral sphincter (SUS) and adipose tissue as the reference site; muscle elasticity was calculated as the strain ratio (SR) of the SUS to the reference site. Evaluations were performed at rest and during PFM contraction. The IC/BPS group completed lower urinary tract symptom and pain questionnaires. SUS SR was compared among the three groups. SUS SR at rest and during PFM contraction was compared among the three groups with the t-test and the Wilcoxon test. Associations between questionnaire results and SUS SR were evaluated by correlation analysis. RESULTS: There was no significant difference in age between the IC/BPS and middle-aged groups, but the young group was significantly younger than the other groups (p < 0.001). SUS SR at rest was significantly higher in the IC/BPS group than in the middle-aged (p = 0.014) and young groups (p = 0.002). Furthermore, in the IC/BPS group, there was no significant difference in SUS SR between at rest and during PFM contraction. SUS SR was not significantly correlated with questionnaire results for lower urinary tract symptoms. CONCLUSIONS: SUS SR at rest was significantly higher in the IC/BPS group than in the young and middle-aged groups.

Influence of fat infiltration, tear size, and post-operative tendon integrity on muscle contractility of repaired supraspinatus muscle.

BACKGROUND: The purpose of this study was to evaluate the effect of fat infiltration, tear size, and post-operative tendon integrity, on post-operative contractility. METHODS: Thirty-five patients who underwent rotator cuff repair were included. The fat infiltration, tear size, and post-operative tendon integrity were evaluated by Goutallier stage, Cofield classification, and Sugaya classification, respectively. The muscle elasticity at rest and at contraction was assessed by real-time tissue elastography pre- and one-year post-operatively. We defined the difference in elasticity between at rest and at contraction as the activity value which reflects muscle contractility. RESULTS: The activity value in patients with Sugaya Type I tended to increase regardless of Cofield classification, whereas those with Sugaya Type III and IV tended to decrease. While the activity value in the patients classified as stage 1 and Type I tended to increase, patients classified as stage 2 showed decreased or constant in contractility even in those subjects classified as Type I. Stepwise multiple regression analysis showed both pre- (p = 0.004, r = -0.47) and post-operative activity values (p = 0.022, r = -0.39) to be significantly correlated only with the Goutallier stage. CONCLUSION: Multiple regression analysis indicated only the Goutallier stage was a significant independent factor for contractility of the supraspinatus muscle. Supraspinatus muscle contractility in patients classified as Types III and IV based on the Sugaya classification tended to decrease post-operatively, while patients whose contractility increased post-operatively were characterized by having a Type I tendon integrity.

The association between renal elasticity evaluated by Real-time tissue elastography and renal fibrosis.

BACKGROUND: The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the severity of renal fibrosis. Real-time tissue elastography (RTE), which measures heartbeat-induced tissue displacement, can assess the elasticity of organs. Here, we aimed to investigate the correlation between renal elasticity and the extent of fibrosis in renal biopsy samples. METHODS: We investigated 29 consecutive patients who underwent a renal biopsy at Ehime University Hospital from February 2018 to August 2019. Renal fibrosis was categorized into three grades, mild (< 25%), moderate (25-50%), and severe (> 50%), based on the total affected area within the biopsy sample. The association between renal elasticity assessed by RTE and the grade of renal fibrosis was evaluated, and a receiver operating characteristic curve was used to distinguish the severity of renal fibrosis. RESULTS: The mean age and estimated glomerular filtration rate (eGFR) were 58.8 years and 55.2 mL/min/1.73 m2, respectively. The median urine protein-to-creatinine ratio was 1.24 g/gCr. The mean renal elasticity of mild, moderate, and severe renal fibrosis was 3.40, 3.98, and 4.77, respectively. Renal elasticity of native kidneys was significantly positively correlated with the grade of renal fibrosis (ρ = 0.529, P = 0.003). At the cutoff point of 3.81, the area under the curve, sensitivity, and specificity were 0.778, 68.4%, and 81.8%, respectively. CONCLUSION: Real-time tissue elastography is a promising, non-invasive method for assessing renal fibrosis in patients with CKD.

Establishing a novel method for assessing elasticity of internal anal sphincter using ultrasonic real-time tissue elastography.

BACKGROUND: Evaluating anorectal function using real-time tissue elastography (RTE) has not been reported. A previous study reported that in the internal anal sphincter (IAS) of surgical specimens of patients with rectal cancer who underwent abdominoperineal resection, there was an increased fibrosis trend in those who underwent pre-operative chemoradiotherapy (CRT) compared with non-CRT. We speculated that CRT might have induced sclerosis of the IAS because of fibrosis. Therefore, we aimed to establish a method of quantitating the degree of IAS hardness using RTE on endoanal ultrasonography. METHODS: RTE was performed with freehand manual compression under a defined pressure at the middle anal canal. Using the most compressive point in the strain graph, we traced the region of interest in the IAS. The strain histogram showed a frequency distribution of colours according to the degree of strain (numeric scan ranging from 0 to 255; smaller number indicated harder tissue). We defined the mean of the strain histogram as 'elasticity'. Ten patients with locally advanced rectal cancer who underwent pre-operative CRT were prospectively enrolled. We statistically evaluated the correlation between IAS elasticity and maximum resting pressure (MRP) values both at pre- and post-CRT. MRP was examined concurrently with the examination of IAS elasticity. RESULTS: Representativity of elasticity measurements was demonstrated. It revealed a trend: IAS elasticity had a moderate inverse correlation with MRP (r = 0.41, P = 0.07), regardless of whether measurements were made before or after CRT. CONCLUSION: We established a completely novel method for the assessment of elasticity of the IAS, using RTE on endoanal ultrasonography.

Noninvasive ultrasound technique for assessment of liver fibrosis and cardiac function in Fontan-associated liver disease: diagnosis based on elastography and hepatic vein waveform type.

PURPOSE: Patients with a Fontan circulation tend to develop liver fibrosis, liver cirrhosis and even hepatocellular carcinoma. A noninvasive ultrasound technique for liver fibrosis and cardiac function assessment in Fontan-associated liver disease (FALD) is needed to evaluate disease progression in real time. This study aimed to evaluate whether hepatic vein (HV) waveform analysis and elastography could be alternative markers to cardiac index (CI) in patients with FALD and assess factors influencing elastography measurements in FALD cases. METHODS: All patients underwent cardiac catheterization, B-mode ultrasound and ultrasound elastography measurement. Moreover, we measured serum markers related to fibrosis and examined HV blood flow using duplex Doppler ultrasonography. RESULTS: Forty-three patients (median age, 17 years; interquartile range, 12-25 years; 29 men, 6 with liver biopsy) were enrolled. The real-time tissue elastography (RTE) value was significantly higher in patients who underwent surgery > 7 years prior, suggesting that this value probably reflects the liver fibrosis due to FALD from the early fibrosis stage. The ultrasound elastography did not significantly correlate with hemodynamic parameters. The area under the receiver operating curve for the diagnosis of CI < 2.2 L/min/m2 using HV waveform was superior to the results from elastography and calculated fibrosis indices. CONCLUSION: HV waveform can be used as a noninvasive measurable surrogate marker for CI. The RTE value increased overtime after the operation and would reflect liver fibrosis. The combination of RTE and HV waveform type could be useful noninvasive tools to evaluate clinical conditions in FALD patients in real time.

Determination of the Relationships Between intra- and Extraoral Tongue Hardness, Thickness, and Pressure Using Ultrasonic Elastography.

Involved with various bodily functions, including ingestion and swallowing, the tongue is an important organ. We measured resting tongue hardness using real-time tissue elastography (RTE) to establish a simple tongue evaluation for patients who may have limited capacities to follow commands. Relationships between tongue hardness, thickness, and pressure were investigated, using both intra- and extraoral probes. Assessments were performed for a total of 27 healthy adults (11 male, 16 female, average age 26.4 ± 1.8 years). Measurements of tongue hardness and thickness were made using strain ratios (SR), and averaged across nine images. Maximum tongue pressure was determined using a tongue pressure device. A negative correlation was observed between intraorally measured tongue hardness and maximum tongue pressure (r = -0.76, p < 0.01). A positive correlation between extraorally measured tongue thickness and maximum tongue pressure was observed (r = 0.59, p < 0.01). Additionally, significant differences were observed between males and females with regards to intraorally measured tongue hardness (p = 0.02), maximum tongue pressure (p = 0.02), and extraorally measured tongue thickness (p < 0.01). The results of this study demonstrated the clinical applicability of RTE-based tongue hardness measurements, and suggest the feasibility of predicting tongue strength based on extraoral tongue thickness measurements.

Liver fibrosis index-based nomograms for identifying esophageal varices in patients with chronic hepatitis B related cirrhosis.

BACKGROUND: Esophageal varices (EV) are the most fatal complication of chronic hepatitis B (CHB) related cirrhosis. The prognosis is poor, especially after the first upper gastrointestinal hemorrhage. AIM: To construct nomograms to predict the risk and severity of EV in patients with CHB related cirrhosis. METHODS: Between 2016 and 2018, the patients with CHB related cirrhosis were recruited and divided into a training or validation cohort at The First Affiliated Hospital of Wenzhou Medical University. Clinical and ultrasonic parameters that were closely related to EV risk and severity were screened out by univariate and multivariate logistic regression analyses, and integrated into two nomograms, respectively. Both nomograms were internally and externally validated by calibration, concordance index (C-index), receiver operating characteristic curve, and decision curve analyses (DCA). RESULTS: A total of 307 patients with CHB related cirrhosis were recruited. The independent risk factors for EV included Child-Pugh class [odds ratio (OR) = 7.705, 95% confidence interval (CI) = 2.169-27.370, P = 0.002], platelet count (OR = 0.992, 95%CI = 0.984-1.000, P = 0.044), splenic portal index (SPI) (OR = 3.895, 95%CI = 1.630-9.308, P = 0.002), and liver fibrosis index (LFI) (OR = 3.603, 95%CI = 1.336-9.719, P = 0.011); those of EV severity included Child-Pugh class (OR = 5.436, 95%CI = 2.112-13.990, P < 0.001), mean portal vein velocity (OR = 1.479, 95%CI = 1.043-2.098, P = 0.028), portal vein diameter (OR = 1.397, 95%CI = 1.021-1.912, P = 0.037), SPI (OR = 1.463, 95%CI = 1.030-2.079, P = 0.034), and LFI (OR = 3.089, 95%CI = 1.442-6.617, P = 0.004). Two nomograms (predicting EV risk and severity, respectively) were well-calibrated and had a favorable discriminative ability, with C-indexes of 0.916 and 0.846 in the training cohort, respectively, higher than those of other predictive indexes, like LFI (C-indexes = 0.781 and 0.738), SPI (C-indexes = 0.805 and 0.714), ratio of platelet count to spleen diameter (PSR) (C-indexes = 0.822 and 0.726), King's score (C-indexes = 0.694 and 0.609), and Lok index (C-indexes = 0.788 and 0.700). The areas under the curves (AUCs) of the two nomograms were 0.916 and 0.846 in the training cohort, respectively, higher than those of LFI (AUCs = 0.781 and 0.738), SPI (AUCs = 0.805 and 0.714), PSR (AUCs = 0.822 and 0.726), King's score (AUCs = 0.694 and 0.609), and Lok index (AUCs = 0.788 and 0.700). Better net benefits were shown in the DCA. The results were validated in the validation cohort. CONCLUSION: Nomograms incorporating clinical and ultrasonic variables are efficient in noninvasively predicting the risk and severity of EV.

Advances in ultrasound elastography for nonalcoholic fatty liver disease.

The prevalence of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) has increased rapidly worldwide, making NAFLD/NASH an important global health problem from both a medical and socioeconomic standpoint. NAFLD is also regarded as a liver component of metabolic syndrome and is reported to be associated with the risk factors for metabolic syndrome. It has been suggested that NAFLD/NASH be recognized both as a liver-specific disease and as an early mediator of systemic diseases. Liver biopsy is recommended as the gold standard method for the diagnosis of NASH and for the staging of liver fibrosis in patients with NAFLD. However, because of its high cost, high risk, and high weightage as a healthcare resource, invasive liver biopsy is a poorly suited diagnostic test for such a highly prevalent condition. Therefore, the development of reliable noninvasive methods for the assessment of liver fibrosis has been sought to estimate the risk of progression of NASH to cirrhosis, estimate the risk of cardiovascular events, aid in the surveillance for HCC, and guide therapy in patients with NAFLD/NASH. In this review, we highlight the principles and recent advances in ultrasound elastography techniques (Real-time Tissue Elastography®, vibration-controlled transient elastography, point shear wave elastography, and two-dimensional shear wave elastography) used to evaluate the liver fibrosis stage and steatosis grade in patients with NAFLD.

Comparison of median nerve stiffness with and without rheumatoid arthritis by ultrasound real-time tissue elastography: A propensity score matching study.

Objectives: This study aimed to compare median nerve stiffness measured by ultrasound real-time tissue elastography in patients with and without rheumatoid arthritis (RA and non-RA groups, respectively).Methods: Altogether, 402 hands of 201 RA group and 222 hands of 111 non-RA group were included in the study. Ultrasonography was performed to evaluate the circumference, cross-sectional area (CSA) and strain ratio as an elasticity of the median nerve at the inlet level of the carpal tunnel and the proximal portion of the carpal tunnel inlet. Using propensity score matching, the difference between RA and non-RA group were analyzed.Results: After propensity score matching, 135 hands in 104 RA group and 70 non-RA group were finally analyzed. There were no significant differences in the circumference and CSA of the median nerve between the two groups. The strain ratio of the median nerve was significantly higher in RA group than in non-RA group only at the inlet of the carpal tunnel level.Conclusions: The nerve stiffness in patients with RA measured by ultrasound real-time tissue elastography was higher than without RA. Inflammatory condition of the flexor tendon and wrist joint in patients with RA may generate fibrotic changes in the median nerve.Trial registration: University Hospital Medical Information Network Clinical Trials Registry: UMIN000015314.

Evaluation of the activities of the medial and lateral heads of quadratus plantae in flexion movements of the lateral four toes using ultrasound real-time tissue elastography.

Quadratus plantae (QP), one of the plantar intrinsic foot muscles, assist plantarflexion of the lesser toes. QP has medial and lateral muscle heads with different anatomical structures. The two heads of this muscle may have different roles in foot function. Ultrasound real-time tissue elastography (RTE) measurements have allowed quantitative assessment of deep-layer muscle elasticity. The purpose of this study was to determine the activity of the QP in flexion movements of the lateral four toes using RTE. Thirteen healthy subjects performed maximal voluntary contractions using a hand-held dynamometer with external belt fixation for each toe flexion movement. The elasticity of the muscles were measured using RTE during rest and flexion of each toe. The strain ratio of the muscle to that in an acoustic coupler was calculated as an index of muscle elasticity. Higher strain ratio values imply lower elasticity. The strain ratio of the medial head of QP for second toe flexion (0.10±0.11) was significantly stiffer than at rest (0.34±0.33). The strain ratios of the lateral head of QP for flexion of the second (0.32±0.19), third (0.41±0.37), fourth (0.33±0.26), and fifth (0.45±0.39) toes were significantly stiffer than at rest (1.02±0.68). These results suggest that the medial head of QP has a role in assisting second-toe flexion, and the lateral head has a role in assisting flexion of all four lateral toes.

Contractile property measurement of the torn supraspinatus muscle using real-time tissue elastography.

HYPOTHESIS: In the restoration of shoulder abduction, decreased contractility of the torn rotator cuff muscle may be a cause of a poor result. The aim of this study was to investigate the relationship between the contractile property of the torn supraspinatus muscle measured by real-time tissue elastography and the Goutallier stage as modified by Fuchs et al. METHODS: The muscular hardness of the torn supraspinatus muscle was measured in 32 patients at rest and during isometric contraction with the shoulder abducted to 60° in the scapular plane. The muscular hardness was calculated as the strain ratio. Fatty degeneration was assessed according to the modified Goutallier stage. Because the activity value (defined as the difference between the strain ratio at rest and the strain ratio during isometric contraction) estimated the contractile property of the muscle, stepwise multiple regression analysis was used to compare the activity value with age, sex, side, time from injury onset to obtaining the measurements, and modified Goutallier stage. RESULTS: The mean activity value was 0.26 ± 0.16. Fatty degeneration of the supraspinatus muscle was grade 0 in 5 patients, grade 1 in 16, grade 2 in 10, and grade 3 in 1. The activity value was significantly correlated only with the modified Goutallier stage (r = -0.78, P < .001). CONCLUSION: The contractile property of the supraspinatus muscles decreased with an increase in the modified Goutallier stage. Real-time tissue elastography can measure the contractile property of the muscles before surgery and thus may be a predictor for the resulting restoration of lost muscle function.

EUS elastography: How to do it?

Strain elastography as used in EUS (EUS-real-time tissue elastography [RTE]) is a qualitative technique and provides information on the relative stiffness between one tissue and another. This article reviews the principles, technique, and interpretation of EUS-RTE in various organs. It includes information on how to optimize the technique as well as a discussion on pitfalls and artifacts. We also refer to the article describing RTE using conventional ultrasound transducers.