Real-time elastography for noninvasive assessment of liver fibrosis in chronic viral hepatitis

Reliability assessment of CT enhancement rate and extracellular volume in liver fibrosis prediction

BACKGROUND

Reliable, non-invasive evaluation of liver fibrosis is essential for early disease management. Computed tomography (CT)-based extracellular volume (ECV) fraction and portal venous phase enhancement rate (VP-ER) have shown potential in quantifying mild-to-moderate fibrosis. This study investigates the diagnostic performance of ECV and VP-ER in differentiating non-significant (F0-F1) from significant (F2-F3) fibrosis in biopsy-confirmed patients.

METHODS

Ninety-three patients (20-72 years, 56.9% male) undergoing liver biopsy and multiphasic CT scans were retrospectively enrolled. Patients with METAVIR F4 cirrhosis or incomplete imaging/pathological data were excluded. Hematocrit levels were obtained on the day of CT. ECV was calculated from differences in liver and aortic attenuation between delayed and enhanced phases, adjusted for hematocrit. VP-ER was derived as the ratio of liver attenuation in venous to portal venous phases multiplied by 100. Spearman's correlation, receiver operating characteristic (ROC) curves, and DeLong tests evaluated their performance. Multiple logistic regression assessed independent contributions of ECV and VP-ER to fibrosis status.

RESULTS

Fifty-three patients had no significant fibrosis (F0-F1) and 40 had significant fibrosis (F2-F3). ECV demonstrated a moderate correlation with fibrosis grade (r = 0.531, p < 0.0001), while VP-ER showed a weaker yet statistically significant correlation (r = 0.363, p = 0.0003). ROC analyses yielded an area under the curve (AUC) of 0.698 for ECV (cut-off = 38%) and 0.763 for VP-ER (cut-off = 71%), with no significant difference between AUCs (p = 0.358). VP-ER accurately classified 70 patients, while ECV correctly predicted 65. Logistic regression revealed significant associations for both VP-ER (OR = 1.08; p = 0.007) and ECV (OR = 1.025; p = 0.0132), achieving 72.04% classification accuracy and an overall AUC of 0.756 (95% CI: 0.688-0.863).

CONCLUSION

ECV fraction and VP-ER demonstrated reliable, complementary capabilities for distinguishing non-significant fibrosis from significant fibrosis. Their combined use in routine multiphasic CT protocols may reduce dependence on invasive biopsy while offering robust sensitivity and specificity for early fibrosis assessment. Further studies including cirrhotic populations and larger cohorts are recommended.

Combi-Elastography versus Transient Elastography for Assessing the Histological Severity of Metabolic Dysfunction-Associated Steatotic Liver Disease

Background/Aims

Combi-elastography is a B-mode ultrasound-based method in which two elastography modalities are utilized simultaneously to assess metabolic dysfunction-associated steatotic liver disease (MASLD). However, the performance of combi-elastography for diagnosing metabolic dysfunction-associated steatohepatitis (MASH) and determining fibrosis severity is unclear. This study compared the diagnostic performances of combi-elastography and vibration-controlled transient elastography (VCTE) for identifying hepatic steatosis, fibrosis, and high-risk MASH.

Methods

Participants who underwent combi-elastography, VCTE, and liver biopsy were selected from a prospective cohort of patients with clinically suspected MASLD. Combi-elastography-related parameters were acquired, and their performances were evaluated using area under the receiver-operating characteristic curve (AUROC) analysis.

Results

A total of 212 participants were included. The diagnostic performance for hepatic steatosis of the attenuation coefficient adjusted by covariates from combi-elastography was comparable to that of the controlled attenuation parameter measured by VCTE (AUROC, 0.85 vs 0.85; p=0.925). The performance of the combi-elastography-derived fibrosis index adjusted by covariates for diagnosing significant fibrosis was comparable to that of liver stiffness measured by VCTE (AUROC, 0.77 vs 0.80; p=0.573). The activity index from combi-elastography adjusted by covariates was equivalent to the FibroScan-aspartate aminotransferase score in diagnosing high-risk MASH among participants with MASLD (AUROC, 0.72 vs 0.74; p=0.792).

Conclusions

The performance of combi-elastography is similar to that of VCTE when evaluating histology of MASLD.

Free-hand ultrasound strain elastography in evaluation of soft tissue tumors

OBJECTIVE

The purpose of this study is to evaluate elastography in a wide spectrum of soft tissue superficial lesions by correlating the elastographic characteristics of these lesions with the elastographic score (ES) system established by Asteria.

METHODS

Forty patients with different superficial lesions of the soft tissues were studied, including lipomas, schwannomas, neuromas, epidermal inclusion cysts, "in transit" melanoma metastasis, arterio-venous malformation, and giant-cell tumor. An ultrasound examination was performed combined with color-Doppler and elastographic module. The B-mode criteria were echogenicity, margins, and structural homogeneity of the lesion. The color-Doppler criterion was irregular and mainly intra-nodular vascularization. ES 1-4 was attributed, in relation with the increasing tissue stiffness, according to the classification of Asteria adapted for soft tissues. Subsequently, we added to each single B-mode and color-Doppler criterion the ES 3 and 4, thus crossing two parameters of malignancy. All the presumptive diagnoses formulated were confirmed with the clinical data or with the histopathological result.

RESULTS

The hypoechoic appearance had the best diagnostic performance. Sensitivity was 87%, specificity 71%, positive predictive value (PPV) 80%, negative predictive value (NPV) 80%, and diagnostic accuracy 80%. There was a good correlation with the clinical and biopsy data, the irregularity of margins the worst performance, the inhomogeneity an intermediate. Color-Doppler had sensitivity 74%, specificity 82%, PPV 85%, NPV 70% and diagnostic accuracy 77.5%. Elastography had sensitivity 87%, specificity 94%, PPV 95%, NPV 84%, and diagnostic accuracy 90%. The combination hypoechoic appearance + ES3/ES4 showed sensitivity 83%, specificity 100%, PPV 100%, NPV 81%,and diagnostic accuracy of 90%. The combination of irregularity of margins + ES3/ES4 showed sensitivity 43%, specificity 100%, PPV 100%, NPV 59%, and diagnostic accuracy of 67.5%. The combination of inhomogeneity of the lesion + ES3/ES4 showed sensitivity 65%, specificity 94%, PPV 94%, NPV 68%, and diagnostic accuracy of 78%. The combination of the color-Doppler with the ES3/ES4 showed sensitivity 69.5%, specificity 100%, PPV 100%, NPV 71%, and diagnostic accuracy of 82.5%.In the combined evaluation, there was a significant increase in specificity, allowing healthy subjects to be categorized as correctly negative, with a reduction in false positives which also translates into an increase in PPV.

CONCLUSIONS

Elastography alone is not sufficient for a correct diagnostic classification and must be considered as an additional parameter in the study of soft-tissue lesions. Although there was a good agreement between B-mode malignancy criteria and ES3/ES4, there is no significant improvement in sensitivity. Ultrasound assessment, especially of superficial lesions, cannot be separated from an integrated approach that foresees the additional and routine use of the elastographic examination.

Diagnostic role of transient elastography in patients with autoimmune liver diseases: A systematic review and meta-analysis

BACKGROUND

Noninvasive methods have been developed to detect fibrosis in many liver diseases due to the limits of liver biopsy. However, previous studies have focused primarily on chronic viral hepatitis and nonalcoholic fatty liver disease. The diagnostic value of transient elastography for autoimmune liver diseases (AILDs) is worth studying.

AIM

To compare the diagnostic accuracy of imaging techniques with serum biomarkers of fibrosis in AILD.

METHODS

The PubMed, Cochrane Library and EMBASE databases were searched. Studies evaluating the efficacy of noninvasive methods in the diagnosis of AILDs [autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC)] were included. The summary area under the receiver operating characteristic curve (AUROC), diagnostic odds ratio, sensitivity and specificity were used to assess the accuracy of these noninvasive methods for staging fibrosis.

RESULTS

A total of 60 articles were included in this study, and the number of patients with AIH, PBC and PSC was 1594, 3126 and 501, respectively. The summary AUROC of transient elastography in the diagnosis of significant fibrosis, advanced fibrosis and cirrhosis in patients with AIH were 0.84, 0.88 and 0.90, respectively, while those in patients with PBC were 0.93, 0.93 and 0.91, respectively. The AUROC of cirrhosis for patients with PSC was 0.95. However, other noninvasive indices (aspartate aminotransferase to platelet ratio index, aspartate aminotransferase/alanine aminotransferase ratio, fibrosis-4 index) had corresponding AUROCs less than 0.80.

CONCLUSION

Transient elastography exerts better diagnostic accuracy in AILD patients, especially in PBC patients. The appropriate cutoff values for staging advanced fibrosis and cirrhosis ranged from 9.6 to 10.7 and 14.4 to 16.9 KPa for PBC patients.

Artificial Intelligence (AI)-Enhanced Ultrasound Techniques Used in Non-Alcoholic Fatty Liver Disease: Are They Ready for Prime Time?

Non-alcoholic fatty liver disease (NAFLD) is the most prevalent cause of chronic liver disease, affecting approximately 2 billion individuals worldwide with a spectrum that can range from simple steatosis to cirrhosis. Typically, the diagnosis of NAFLD is based on imaging studies, but the gold standard remains liver biopsies. Hence, the use of artificial intelligence (AI) in this field, which has recently undergone rapid development in various aspects of medicine, has the potential to accurately diagnose NAFLD and steatohepatitis (NASH). This paper provides an overview of the latest research that employs AI for the diagnosis and staging of NAFLD, as well as applications for future developments in this field.

The severity of portal hypertension by a non-invasive assessment: acoustic structure quantification analysis of liver parenchyma

Background

Acoustic structure quantification (ASQ) has been applied to evaluate liver histologic changes by analyzing the speckle pattern seen on B-mode ultrasound. We aimed to assess the severity of portal hypertension (PHT) through hepatic ultrasonography.

Methods

Sixty patients diagnosed with PHT and underwent surgical treatment with portosystemic shunts were enrolled. Portal pressure (PP) was measured intraoperatively. Patients were divided into subgroups according to the severity of gastroesophageal varices and Child–Pugh class. Three difference ratio (C_m²) values on ASQ histogram mode were analyzed for their relationships with PP, degree of gastroesophageal varices and Child–Pugh liver function. Thirty healthy volunteers matched with the patients for gender and age were enrolled as controls. Comparisons among groups and correlation of the parameters with PP were analyzed. Area under the receive operating characteristic curve was used to evaluate the predicting value of ASQ parameters.

Results

In the patients, the ASQ parameters peak C_m² (C_m²_max), mean C_m² (C_m²_mean) and the highest occurred C_m² value of the obtained red curve (R_maxC_m²) were all greatly increased (P < 0.0001, P < 0.0001, P = 0.027). Multiple comparisons indicated that, regardless of Child–Pugh class and degree of gastroesophageal varices, the patients had significantly increased C_m²_max and C_m²_mean compared with the controls (all P < 0.0001). No differences among subgroups were observed. C_m²_max was significantly statistically correlated with PP (r = 0.3505, P < 0.01), degree of varices (r = 0.4998, P < 0.0001). Youden’s index for C_m²_max with a cut-off value of 140.3 for predicting the presence of PHT, gastroesophageal varices and liver function equal to or worse than Child–Pugh class B were 0.8, 0.91 and 0.84, respectively.

Conclusions

ASQ analysis of ultrasonographic images may have a role in the evaluation of the severity of PHT by detecting liver histologic changes in the speckle pattern caused by cirrhosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12880-022-00817-2.

Evaluation of liver fibrosis in chronic hepatitis B patients with 2D shear wave elastography with propagation map guidance: a single-centre study

Background

The aims of this study were to evaluate liver fibrosis with two-dimensional (2D) shear wave elastography (SWE) in patients with chronic hepatitis B (CHB), to compare 2D-SWE with histopathology and to determine the change in liver stiffness values after antiviral therapy.

Material and methods

A total of 253 patients with CHB were included in this prospective study. 2D-SWE with propagation map guidance to measure liver stiffness, fibrosis-4 index (FIB-4) and aspartate aminotransferase to platelet ratio index (APRI) scoring and additional liver biopsy were performed in patients with CHB. Liver stiffness was measured again at 24 and 48 weeks in all patients. The Spearman rank correlation test was used to analyse the correlation between variables, and receiver operating curve analysis was used to evaluate the diagnostic performance in terms of fibrosis.

Results

Liver stiffness measurements made with 2D-SWE demonstrated a significant positive correlation with the fibrosis stage and FIB-4 score (r_s = 0.774 and 0.337, respectively, p < 0.001 for both). The area under the curve value for kPa for the prediction of significant fibrosis was 0.956 (95% CI_s) (0.920–0.991), and the optimal cut-off value was 8.2 kPa (sensitivity: 92.7% and specificity: 78.9%); these values were 0.978 (95% CI_s, 0.945–1.000) and 10.1 kPa (sensitivity: 92.9% and specificity: 96.4%) for the prediction of severe fibrosis. After antiviral treatment, a decrease in liver stiffness values measured by 2D-SWE was detected (mean kPa values at 0 and 48 weeks; 9.24 and 7.36, respectively, p < 0.001).

Conclusion

In conclusion, the measurement of liver stiffness with 2D-SWE has high diagnostic performance in the determination of hepatic fibrosis and can be used to evaluate the response to treatment in patients receiving antiviral therapy.

Effects of Confounding Factors on Liver Stiffness in Two-Dimensional Shear Wave Elastography in Beagle Dogs

Background

Two-dimensional shear wave elastography (2D-SWE) is a powerful technique that can non-invasively measure liver stiffness to assess hepatic fibrosis.

Purpose

This study aimed to identify the effects of confounding factors, including anesthesia, breathing, and scanning approach, on liver stiffness when performing 2D-SWE in dogs.

Materials and Methods

Nine healthy Beagle dogs were included in this study. Hepatic 2D-SWE was performed, and liver stiffness was compared between conscious and anesthetized states, free-breathing and breath-holding conditions, and intercostal and subcostal approaches. For the anesthetized state, the breath-holding condition was subdivided into seven phases, which included forced-expiration (5 and 10 mL/kg), end-expiration (0 cm H₂O), and forced-inspiration (5, 10, 15, and 20 cm H₂O), and liver stiffness was compared among these phases. Changes in liver stiffness were compared between intercostal and subcostal approaches according to breathing phases.

Results

No significant difference was observed in liver stiffness between the conscious and anesthetized states or between the free-breathing and breath-holding conditions. No significant difference was noted in liver stiffness among the breathing phases, except for forced-inspiration with high airway pressure (15 and 20 cm H₂O in the intercostal approach and 10, 15, and 20 cm H₂O in the subcostal approach), which was associated with significantly higher liver stiffness (p < 0.05). Liver stiffness was significantly higher in the subcostal approach than in the intercostal approach (p < 0.05). Changes in liver stiffness were significantly higher in the subcostal approach than in the intercostal approach in all forced-inspiratory phases (p < 0.05).

Conclusion

In conclusion, when performing 2D-SWE in dogs, liver stiffness is unaffected by anesthesia and free-breathing. To avoid inadvertent increases in liver stiffness, the deep inspiratory phase and subcostal approach are not recommended. Thus, liver stiffness should be interpreted considering these confounding factors.

Uncertainty of Liver Cirrhosis Diagnosis and Use of Elastography

A case of severe jaundice in a patient with a long history of alcohol abuse led to a questionable diagnosis of liver cirrhosis. To determine its diagnostic utility in the setting of liver disease, elastography was utilized on our patient to confirm the clinically suspected diagnosis of cirrhosis.

A 59-year-old male presented to our emergency department (ED) with two days of progressive jaundice and right upper quadrant (RUQ) pain. The patient admitted to drinking > 500 mL of vodka daily for the last seven years, with his last drink on the morning of admission. Physical exam revealed a man in mild acute distress with severe jaundice and an abdomen diffusely tender to palpation. Two spider angiomas were present on the torso along with caput medusae and mild asterixis. Labs revealed aspartate aminotransferase (AST) 408, alanine aminotransferase (ALT) 69, prothrombin time (PT) 16.3, partial thromboplastin time (PTT) 36, total bilirubin 22.6, and direct bilirubin 19.9 mg/dL. While admitted, total bilirubin rose as high as 31.5 mg/dL. Examination showed a Model for End-Stage Liver Disease (MELD) score of 22 and a Maddrey score of 37. Ultrasound revealed moderate hepatosplenomegaly with no signs of pancreatitis.

Based on the patient’s history of alcohol abuse paired with physical exam findings and elevated laboratory markers, we were able to diagnose with a high level of suspicion that this patient was suffering from chronic alcoholic liver disease, exacerbated by an acute episode of alcoholic hepatitis, which led to hepatic encephalopathy. Based on these findings, a diagnosis of liver cirrhosis was suspected; however, this diagnosis required further confirmation. We utilized ultrasound elastography to measure the velocity of shear wave transmission in the liver of our patient. A literature review was conducted on the use of elastography for the diagnosis of liver disease, and a significant correlation between the velocity of shear wave transmission and hepatic histological findings was identified. Elastography revealed a mean velocity of shear wave transmission of 1.77 m/s in our patient. This finding is consistent with a Meta-analysis of Histological Data in Viral Hepatitis (METAVIR) score of F = 4, indicating significant fibrosis and confirming the suspected diagnosis of alcohol-induced liver cirrhosis.

As a non-invasive and inexpensive diagnostic tool, elastography demonstrates significant potential for clinical utility in patients with liver disease. Clinicians may benefit from the use of elastography in diagnosis, while patients may receive both therapeutic and prognostic benefits secondary to its use. In similar cases with clinical uncertainty, elastography can reliably identify the presence of fibrous tissue in the liver without tissue biopsy, thus aiding in clinical diagnoses and enabling the use of optimal therapeutic regimens for future patients.

The impact of body position and exercise on the measurement of liver Young's modulus by real-time shear wave elastography

BACKGROUND

In the past ten years, liver biopsies have been used as a method to accurately diagnose the stage of fibrosis.

OBJECTIVE

This study aimed to evaluate whether body position and exercise affect the measurement of liver Young's modulus of healthy volunteers by real-time shear wave elastography (RT-SWE).

METHODS

RT-SWE was used to measure liver Young's modulus in the supine and left lateral positions of 70 healthy volunteers at rest and measure the liver Young's modulus in the lying position before exercise, and at zero, five, and ten minutes of rest after exercise.

RESULTS

The liver Young's modulus in the left lateral position was significantly higher than in the supine position (P< 0.05), and the measured value in the supine position was more stable than the left lateral position. The liver Young's modulus measured at zero minutes after exercise was significantly higher than that measured before exercise (P< 0.05). The liver Young's modulus measured at five minutes after exercise was significantly higher than that measured at zero minutes after exercise (P<0.05) and was not statistically different from the measured value before exercise (P> 0.05). The liver Young's modulus measured at ten minutes after exercise was significantly higher from that measured at zero minutes after exercise (P< 0.05) and was not statistically different from the measured value at five minutes after exercise (P> 0.05).

CONCLUSION

Body position and exercise have a significant impact on the measurement of liver Young's modulus. It is recommended that the examinees take a supine position during the measurement, and measurement should be conducted at least ten minutes after exercise.

Causal contributors to tissue stiffness and clinical relevance in urology

Mechanomedicine is an emerging field focused on characterizing mechanical changes in cells and tissues coupled with a specific disease. Understanding the mechanical cues that drive disease progression, and whether tissue stiffening can precede disease development, is crucial in order to define new mechanical biomarkers to improve and develop diagnostic and prognostic tools. Classically known stromal regulators, such as fibroblasts, and more recently acknowledged factors such as the microbiome and extracellular vesicles, play a crucial role in modifications to the stroma and extracellular matrix (ECM). These modifications ultimately lead to an alteration of the mechanical properties (stiffness) of the tissue, contributing to disease onset and progression. We describe here classic and emerging mediators of ECM remodeling, and discuss state-of-the-art studies characterizing mechanical fingerprints of urological diseases, showing a general trend between increased tissue stiffness and severity of disease. Finally, we point to the clinical potential of tissue stiffness as a diagnostic and prognostic factor in the urological field, as well as a possible target for new innovative drugs.

Role of shear wave elastography in treatment follow-up of leprosy neuropathy

PURPOSE

Grayscale ultrasonography when complemented with shear wave elastography helps in better evaluation of treatment response of leprosy neuropathy and in guiding appropriate management of the patient. There is limited literature regarding the use of shear wave elastography in ulnar nerve neuropathy. Our purpose was to evaluate the role of shear wave elastography in assessing stiffness changes within the ulnar nerve during treatment of leprosy.

METHODS

This was a prospective study which included 30 patients diagnosed with leprosy neuropathy. Recruited patients were followed up, during the course of treatment, i.e. for 1 year. Serial ultrasonography of these patients was done at 0, 3, 6 and 12 months interval.

RESULTS

Significant (P < 0.05) decrease in elastography parameters was seen in transverse imaging plane between first and third, as well as first and fourth visits (mean stiffness and velocity pretreatment ~ 25.78 ± 18 kPa and 2.74 ± 0.98 m/s, mean stiffness and velocity post-treatment 15.67 ± 5.89 kPa and 2.24 ± 0.428 m/s). Although elastography parameters decreased during these visits in the long-axis imaging plane, they were not found to be statistically significant. However, gross morphology and cross-sectional area of the nerve did not change significantly across visits. Interestingly, elastography values were higher in patients with neuritis, though not statistically significant.

CONCLUSION

Shear wave elastography is a novel, upcoming modality in musculoskeletal imaging especially in the evaluation of peripheral neuropathy. It can act as an adjunct to grey-scale imaging, which can help in early diagnosis and in guiding treatment of leprosy neuropathy.

A Comparison Study of Conventional Ultrasound and Ultrasound Strain Elastography in the Evaluation of Myopathy

The aim of this study was to compare ultrasound strain elastography (USE) with conventional ultrasonography echogenicity (EL) in detecting muscle pathology. For conventional ultrasonography, biceps EL was obtained. For USE, elasticity index (EI) of biceps was represented as a range, from 0 (softest) to 6 (hardest). Muscle-to-fats elasticity ratio compared EI of muscle with that of surrounding fats. Color distribution of elastogram was analyzed using open-source ImageJ software showing % red, % green, and % blue within a region of interest. Increased biceps EL, decreased biceps EI, and elasticity ratio were observed in patients with myopathy. In the color elastogram, there is no significant difference in % green between healthy control and patient, but significance was observed in % red and % blue (P < 0.001). Utilization of USE parameters has increased sensitivity up to 100% compared with 63% with conventional US. It is a promising adjunct for the clinical diagnosis of myopathy.

Evaluation of Optic Nerve Head Biomechanical Properties in Pseudoexfoliation Glaucoma with Real-time Elastography

PURPOSE

To investigate the biomechanical properties of the optic nerve head in patients with Pseudoexfoliation (PEX) glaucoma using Real-time Elastography (RTE) and to compare these results with those of Primary Open Angle Glaucoma (POAG) patients and healthy subjects.

METHODS

Twenty eyes of 20 PEX glaucoma patients (PEX group), 20 eyes of 20 POAG patients (POAG group), and 20 eyes of 20 healthy subjects (control group) were enrolled in this prospective study. The strain Ratios of Orbital Fat to Optic Nerve head (ROFON) and lateral rectus muscle to optic nerve head (RLRON) were determined. Comparisons were performed using Chi-square, Kruskal Wallis, Mann-Whitney U, and One-way ANOVA tests.

RESULTS

The strain ratios of orbital fat to optic nerve head were 2.34, 6.85 and 1.76 in PEX glaucoma, POAG, and control groups, respectively (p<0.001). The strain ratios of the lateral rectus muscle to the optic nerve head were 0.51, 0.82, and 0.55 in PEX glaucoma, POAG, and control groups, respectively (p=0.256).

CONCLUSION

The strain ratios of orbital fat to optic nerve head were different in PEX glaucoma patients than in POAG and control groups. RTE can provide biomechanical assessment of the optic nerve head in a non-invasive, quick, easily accessible, and user-friendly manner.

Endogenous motion of liver correlates to the severity of portal hypertension

BACKGROUND

Degree of portal hypertension (PH) is the most important prognostic factor for the decompensation of liver cirrhosis and death, therefore adequate care for patients with liver cirrhosis requires timely detection and evaluation of the presence of clinically significant PH (CSPH) and severe PH (SPH). As the most accurate method for the assessment of PH is an invasive direct measurement of hepatic venous pressure gradient (HVPG), the search for non-invasive methods to diagnose these conditions is actively ongoing.

AIM

To evaluate the feasibility of parameters of endogenously induced displacements and strain of liver to assess degree of PH.

METHODS

Of 36 patients with liver cirrhosis and measured HVPG were included in the case-control study. Endogenous motion of the liver was characterized by derived parameters of region average tissue displacement signal (d_antero, d_retro, d_RMS) and results of endogenous tissue strain imaging using specific radiofrequency signal processing algorithm. Average endogenous strain µ and standard deviation σ of strain were assessed in the regions of interest (ROI) (1 cm × 1 cm and 2 cm × 2 cm in size) and different frequency subbands of endogenous motion (0-10 Hz and 10-20 Hz).

RESULTS

Four parameters showed statistically significant (P < 0.05) correlation with HVPG measurement. The strongest correlation was obtained for the standard deviation of strain (estimated at 0-10 Hz and 2 cm × 2 cm ROI size). Three parameters showed statistically significant differences between patient groups with CSPH, but only d_retro showed significant results in SPH analysis. According to ROC analysis area under the curve (AUC) of the σ_{ROI[0…10Hz, 2 cm × 2 cm]} parameter reached 0.71 (P = 0.036) for the diagnosis of CSPH; with a cut-off value of 1.28 μm/cm providing 73% sensitivity and 70% specificity. AUC for the diagnosis of CSPH for µ_{ROI[0…10Hz, 1 cm × 1 cm]} was 0.78 (P = 0.0024); with a cut-off value of 3.92 μm/cm providing 73% sensitivity and 80% specificity. D_retro parameter had an AUC of 0.86 (P = 0.0001) for the diagnosis of CSPH and 0.84 (P = 0.0001) for the diagnosis of SPH. A cut-off value of -132.34 μm yielded 100% sensitivity for both conditions, whereas specificity was 80% and 72% for CSPH and SPH respectively.

CONCLUSION

The parameters of endogenously induced displacements and strain of the liver correlated with HVPG and might be used for non-invasive diagnosis of PH.

Reliability of shoulder muscle stiffness measurement using strain ultrasound elastography and an acoustic coupler

PURPOSE

Abnormal increases in muscle tone can be caused by various musculoskeletal disorders. The objective of this study was to evaluate intratester and intertester reliabilities in measuring the stiffness of the shoulder muscles using strain ultrasound elastography (USE) and an acoustic coupler.

METHOD

Tissue stiffness was measured in the trapezius muscle and in the supraspinatus muscle of healthy young volunteers.

RESULTS

The mean strain ratios measured by two experienced shoulder surgeons were significantly higher in the trapezius muscle than in the supraspinatus muscle (P < 0.001). Intratester reliability was rated as moderate to substantial for the trapezius muscle and substantial for the supraspinatus muscle. Intertester reliability was substantial for both muscles, with an intraclass correlation coefficient (2,1) of 0.62 [95% confidence interval (CI) 0.28-0.82] for the trapezius muscle and 0.69 (95% CI 0.40-0.86) for the supraspinatus muscle.

CONCLUSIONS

We found substantial intratester and intertester reliabilities for the trapezius and supraspinatus muscles, suggesting that USE represents a promising modality for measuring the stiffness of shoulder muscles. However, the clinical application of this method will require the development of a device that can standardize the scanning technique to further increase the reliability.

The diagnostic value of two-dimensional shear wave elastography in gestational diabetes mellitus

OBJECTIVE

The aim of our study is to establish the reference range of Young's modulus values of placenta in normal pregnancies and to evaluate the diagnostic value of two-dimensional shear wave elastography (2D-SWE) in gestational diabetes mellitus (GDM).

METHODS

A total of 223 normal pregnant women, 22 pregnancies complicated by A1GDM (controlled by diet), and 14 pregnancies complicated by A2GDM (controlled by medication) were recruited for this study. The elasticity values of the central parts of the placentas were determined by 2D-SWE imaging. The mean value (E_mean), min value (E_min), and max value (E_max) of the placentas were recorded. Twenty placentas were randomly selected for reliability analysis.

RESULTS

(1) All values (E_mean, E_min, E_max) showed great repeatability and consistency. (2) The reference range of Young's modulus values of placentas in normal pregnancies were E_mean (4.12 ± 0.83), E_min (2.15 ± 0.83) and E_max (6.72 ± 1.43). No significant correlations were observed between elasticity values and gestational age (r < 0.3, p > 0.05) or between elasticity values and placental maturity (r < 0.3, p > 0.05). (3) The Young's modulus values in the A1 GDM and A2 GDM women were E_mean (6.39 ± 1.74), E_min (2.95 ± 1.05), E_max (10.78 ± 2.94) and E_mean (11.96 ± 7.29), E_min (6.79 ± 4.70a), E_max (18.94 ± 11.61) respectively. All values were significantly higher in GDM pregnancies than in normal pregnancies (p < 0.05). A2GDM pregnancies had higher values than A1GDM pregnancies (p < 0.05).

CONCLUSION

Placental elasticity is independent of gestational age and placental maturity. 2D-SWE can play an important role in diagnosing GDM by assessing placental hardness.

Utility of Ultrasound Strain Elastography to Differentiate Benign from Malignant Lesions of the Breast

Background

The purpose of this study was to determine the utility and diagnostic performance of strain elastography (SE) in differentiating benign from malignant lesions of the breast.

Methods

In this prospective study, 50 palpable breast masses in 50 patients were examined by mammography, B-mode ultrasound (US) and SE. Lesions were categorized using Breast Imaging Reporting and Data System (BIRADS) scoring based on mammographic and sonographic features. Elasticity scores were assessed on a five-point scale based on the distribution of strain, and the lesion size on SE imaging and B-mode (elasticity imaging/B mode [EI/B] ratio) was compared. Findings were correlated with the BIRADS assessment and diagnostic performance of sonoelastography was evaluated taking histopathology as reference standard.

Results

Histopathology revealed 29 (58%) malignant and 21 (42%) benign lesions. Infiltrative ductal carcinoma and fibroadenoma were the most common malignant and benign lesions, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of SE was 100%, 76.1%, 85.2%, 100%, and 90%, respectively. Higher elasticity score was significantly associated with malignant histopathology (P < 0.00001). The mean EI/B ratio for malignant lesions was 1.36 ± 0.24 while that of benign lesions was 1.03 ± 0.30 (P = 0.000).

Conclusion

Real-time SE of the breast, with its superior sensitivity and specificity, could provide improved characterization of benign and malignant breast masses compared with mammography and conventional US. Due to greater diagnostic accuracy, SE can be an effective adjunctive tool to B-mode US in predicting malignancy of breast, as well as in reducing the need for biopsies in benign breast lesions.

Utility of Ultrasound Elastography to Differentiate Benign from Malignant Cervical Lymph Nodes

Background:

The purpose of this study was to evaluate the usefulness of strain elastography and acoustic radiation force impulse (ARFI) imaging in the differentiation of benign and malignant cervical lymph nodes (LNs).

Materials and Methods:

In this prospective study, 50 enlarged cervical LNs (33 benign and 17 malignant) were examined by B-mode ultrasound (US), color Doppler, and strain elastography. Elastographic patterns (1–5) were categorized based on distribution of hard area within LN. The shear wave velocity (SWV) of LNs was evaluated by ARFI imaging. Diagnostic performance of sonoelastographic parameters was compared taking histopathology of LN as a reference standard. Optimal cutoff value of the mean SWV values for predicting malignancy was determined using receiver operating characteristic curve analysis.

Results:

Among US parameters, borders of LN had the highest diagnostic accuracy (80%), while echogenicity had the least (48%). Majority of benign LNs (n = 31) had elastography patterns 1 and 2, while majority of malignant LNs (n = 16) had patterns 3–5 (P = 0.000). The sensitivity, specificity, and accuracy of elastography were 94.1%, 93.9%, and 94%, respectively. The mean SWV of benign LNs (1.670 ± 0.367 m/s) differed significantly from malignant LNs (2.965 ± 0.826 m/s; P = 0.000). A cutoff value of 2.05 m/s predicted malignancy with 88.2% sensitivity and 84.8% specificity and gave an area under the curve of 0.949 (95% confidence interval: 0.70–1.20).

Conclusion:

Elastography has high diagnostic accuracy in differentiating benign and malignant cervical LNs and can be potentially useful in selecting the LN with high probability of malignancy, on which fine-needle aspiration cytology/biopsy can be performed.

CHD is Associated With Higher Grades of NAFLD Predicted by Liver Stiffness

BACKGROUND AND AIM

Accumulating clinical and epidemiologic evidence indicates that nonalcoholic fatty liver disease (NAFLD) is not only associated with liver-related morbidity and mortality, but also with a greater risk of coronary heart disease (CHD). However, there is currently no diagnostic parameter for NAFLD that has been determined to reliably indicate the presence of CHD as a co-morbidity. We evaluated the liver stiffness and visceral fat thickness of NAFLD patients ultrasonographically to explore the relationship between liver stiffness, visceral fat thickness, and CHD, aiming to find explore the relationship between the liver stiffness and CHD.

METHODS

We enrolled 120 consecutive patients who had been initially diagnosed with CHD on the basis of their symptoms. All patients underwent coronary angiography or computed tomography angiography, and were classified into a CHD group and a non-CHD group on the basis of the results. All patients underwent liver ultrasonography, shear-wave elastography, and visceral fat thickness measurement.

RESULTS

NAFLD and visceral fat thickness were significantly positively correlated with CHD and Gensini score (P<0.001). Multivariate regression showed that age, male, cholesterol, liver stiffness, and visceral fat thickness were determinants of CHD. Age, cholesterol, liver stiffness, and visceral fat thickness cut-off points for the prediction of CHD were above 50 years old [area under the curve (AUC): 0.678; sensitivity, 87%; specificity, 42.6%], >3.76 mmol/L (AUC: 0.687; sensitivity, 68.4%; specificity, 64.8%), >6.1 kPa (AUC: 0.798; sensitivity, 50%; specificity, 92.6%), and >7.41 cm (AUC: 0.694; sensitivity, 52.6%; specificity, 87%), respectively. Compared with the use of age, gender, and cholesterol (model 1), the addition of the liver stiffness cut-off to model 1 resulted in a stronger predictive value (P=0.005).

CONCLUSIONS

High-grade NAFLD is more present in symptomatic CHD. The higher degree of liver stiffness in patients with NAFLD, the higher risk of CHD in these NAFLD patients.

Diagnostic performance on multiple parameters of real-time ultrasound shear wave elastography for evaluating nonalcoholic fatty liver disease: A rabbit model

OBJECTIVE

To study the diagnostic value of real-time ultrasound shear wave elastography (US-SWE) in evaluating the histological stages of nonalcoholic fatty liver disease (NAFLD) in a rabbit model.

MATERIALS AND METHODS

Twenty-one 8-week-old rabbits were fed a high-fat, high-cholesterol diet (experimental groups), and seven rabbits were fed a standard diet (control group). All rabbits underwent real-time US-SWE at various time points to document the histological stages of NAFLD. We categorized the histological stages as normal, NAFL, borderline nonalcoholic steatohepatitis (NASH), and NASH. We measured the elastic modulus of the liver parenchyma and analyzed the diagnostic efficacy of real-time US-SWE using the area under receiver operating characteristic curve (AUC) for the four histological stages.

RESULTS

The mean, minimum, and maximum elastic modulus increase for NAFL, borderline NASH, and NASH. For the mean, minimum, and maximum elastic modulus, AUCs are 0.891 (95% confidence interval [CI]: 0.716-0.977), 0.867 (95% CI: 0.686-0.965), and 0.789 (95% CI:0.594-0.919) for differentiating normal liver from liver with NAFLD, respectively; AUCs are 0.846 (95% CI: 0.660-0.954), 0.818 (95% CI: 0.627-0.937), and 0.797 (95% CI:0.627-0.913) for differentiating normal liver or liver with NAFL from liver with borderline NASH or NASH, respectively; AUCs are 0.889 (95% CI: 0.713-0.976), 0.787 (95% CI: 0.591-0.918), and 0.895 (95% CI:0.720-0.978) for differentiating liver with NASH from liver with lower severity NAFLD or normal liver, respectively.

CONCLUSIONS

Real-time US-SWE is an accurate, noninvasive technique for evaluating the histological stages of NAFLD by measuring liver stiffness. We recommend using the mean elastic modulus to differentiate the histological stages, with the minimum and maximum elastic modulus as valuable complements.

Comparing point shear wave elastography (ElastPQ) and transient elastography for diagnosis of fibrosis stage in non-alcoholic fatty liver disease

BACKGROUND AND AIM

Transient elastography (TE) and point shear wave elastography (pSWE) are noninvasive methods to diagnose fibrosis stage in patients with chronic liver disease. The aim of this study is to compare the accuracy of the two methods to diagnose fibrosis stage in non-alcoholic fatty liver disease (NAFLD) and to study the intra-observer and inter-observer variability when the examinations were performed by healthcare personnel of different backgrounds.

METHODS

Consecutive NAFLD patients who underwent liver biopsy were enrolled in this study and had two sets each of pSWE and TE examinations by a nurse and a doctor on the same day of liver biopsy procedure. The medians of the four sets of pSWE and TE were used for evaluation of diagnostic accuracy using area under receiver operating characteristic curve (AUROC). Intra-observer and inter-observer variability was analyzed using intraclass correlation coefficients.

RESULTS

Data for 100 NAFLD patients (mean age 57.1 ± 10.2 years; male 46.0%) were analyzed. The AUROC of TE for diagnosis of fibrosis stage ≥ F1, ≥ F2, ≥ F3, and F4 was 0.89, 0.83, 0.83, and 0.89, respectively. The corresponding AUROC of pSWE was 0.80, 0.72, 0.69, and 0.79, respectively. TE was significantly better than pSWE for the diagnosis of fibrosis stages ≥ F2 and ≥ F3. The intra-observer and inter-observer variability of TE and pSWE measurements by the nurse and doctor was excellent with intraclass correlation coefficient > 0.96.

CONCLUSION

Transient elastography was significantly better than pSWE for the diagnosis of fibrosis stage ≥ F2 and ≥ F3. Both TE and pSWE had excellent intra-observer and inter-observer variability when performed by healthcare personnel of different backgrounds.

Strain elastography for noninvasive assessment of liver fibrosis: A prospective study with histological comparison

The aim of this study was to prospectively evaluate the diagnostic performance of strain elastography for the assessment of liver fibrosis in patients with chronic liver disease using Ishak (0-6) histology stage as a reference standard. Ninety-eight consecutive patients with suspected chronic liver disease scheduled for liver biopsy (n = 78) or histologically confirmed cirrhosis (n = 20) were enrolled. Liver fibrosis Index (LF Index) calculated by strain elastography, liver stiffness by transient elastography and serum fibrosis markers (aspartate aminotransferase-to-platelet ratio index and King's Score) were measured. Spearman's correlation coefficient between the LF Index, liver stiffness, serum fibrosis markers and fibrosis stage were calculated and compared using areas under the receiver-operating characteristics (AUROCs) curves. Among 73 patients who underwent strain elastography, there was weak correlation between fibrosis stage and the LF Index (Spearman's: ρ = 0.385 for Ishak score; P = 0.001). Among 52 patients who underwent strain elastography and transient elastography, the AUROC values using LF Index, transient elastography, aspartate aminotransferase-to-platelet ratio index and King's Score for diagnosing significant fibrosis (Ishak score ≥ 3) were 0.79, 0.87, 0.86 and 0.85, respectively (P < 0.0001) and for diagnosing severe fibrosis/cirrhosis (Ishak score ≥ 5) were 0.83, 0.94, 0.92 and 0.92, respectively (P < 0.0001). When comparing the diagnostic performance using LF Index, transient elastography, aspartate aminotransferase-to-platelet ratio index and King's Score, transient elastography shows a significantly higher AUROC value than LF Index in detecting severe fibrosis (P = 0.0149). The diagnostic performance of LF Index calculated by strain elastography was not statistically significantly different to the other noninvasive tests for the assessment of significant liver fibrosis but inferior to transient elastography for the assessment of severe fibrosis/cirrhosis.

Comparison of Diagnostic Performance of B-Mode Ultrasonography and Shear Wave Elastography in Cervical Lymph Nodes

The purpose of this study was to compare the diagnostic performance of B-mode ultrasonography (US) and shear wave elastography (SWE) for differentiating benign from malignant cervical lymph nodes (LNs). This study evaluated 130 cervical LNs in 127 patients. On conventional B-mode US, short-axis and long-axis diameters, long-to-short-axis ratio, cortical morphology, border, and presence of necrosis or calcification were evaluated. Maximum elasticity value (Emax) was collected for SWE. The area under the receiver operator characteristic curve (AUC), sensitivity, and specificity of B-mode US features and SWE were compared. Final histopathologic results showed 89 benign and 41 metastatic LNs. Among the B-mode US features, cortical morphology had the highest AUC (0.884). When 54 kPa of Emax was applied as a cutoff value, the SWE showed significantly lower AUC than cortical morphology (0.734, P = 0.02). Both sensitivity and specificity for cortical morphology on B-mode US were higher than for Emax (80.5% vs 65.9%, P = 0.212 and 89.9% vs 76.4%, P = 0.026, respectively). Conventional B-mode US resulted in higher diagnostic yield than SWE in evaluating cervical LNs in our study. However, further studies on potential factors that may affect the SWE velocity are needed to validate the diagnostic value of SWE.

A noninvasive indicator for the diagnosis of early hepatitis B virus-related liver fibrosis

BACKGROUND AND AIMS

Liver stiffness measurement (LSM) detected by FibroScan, combined with biochemical indexes, has shown potential values for assessment of liver fibrosis pathological degrees. Here we aimed to investigate a noninvasive method for hepatitis B virus-related liver fibrosis.

PATIENTS AND METHODS

In all, 307 patients who underwent liver biopsy and LSM measurement were included. Inflammation grades and fibrosis stages were evaluated according to METAVIR scoring system. Spearman's rank correlation analysis, logistic regression analysis, and receiver operating characteristic (ROC) curves analysis were performed to assess the factors' role in inflammation grades/fibrosis stages.

RESULTS

Spearman's rank correlation analysis showed that LSM, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and AST-to-platelet ratio index were positively correlated with inflammation grades and histologic fibrosis stages; platelets showed negative correlation, and AST-to-ALT ratio was not related. Logistic regression analysis indicated that LSM and APRI were risk factors for inflammation grades; LSM was the independent risk factor for fibrosis stages, P<0.0001, odds ratio>1. ROC curve analysis found LSM cutoff values and areas under the curve for the diagnosis of fibrosis scores: 6.95 and 0.804, respectively, for the diagnosis of significant fibrosis (F≥F2); 10.35 and 0.856, respectively, for severe fibrosis (F≥F3); 11.35 and 0.897, respectively, for cirrhosis (F=F4). Considering ALT as a confounding factor, ROC analysis was repeated in patients with normal and elevated ALT separately; the results indicated that when ALT was up to 40 U/l, LSM cutoff value and areas under the curve for the diagnosis of significant fibrosis (F≥F2) were 6.55 and 0.748, respectively.

CONCLUSION

This study provided a noninvasive treatment and prevention indicator for early hepatitis B virus-related liver fibrosis.

Evaluation of texture features at staging liver fibrosis based on phase contrast X-ray imaging

BACKGROUND

The purpose of this study is to explore the potential of phase contrast imaging to detect fibrotic progress in its early stage; to investigate the feasibility of texture features for quantified diagnosis of liver fibrosis; and to evaluate the performance of back propagation (BP) neural net classifier for characterization and classification of liver fibrosis.

METHODS

Fibrous mouse liver samples were imaged by X-ray phase contrast imaging, nine texture measures based on gray-level co-occurrence matrix were calculated and the feasibility of texture features in the characterization and discrimination of liver fibrosis at early stages was investigated. Furthermore, 36 or 18 features were applied to the input of BP classifier; the classification performance was evaluated using receiver operating characteristic curve.

RESULTS

The phase contrast images displayed a vary degree of texture pattern from normal to severe fibrosis stages. The BP classifier could distinguish liver fibrosis among normal, mild, moderate and severe stages; the average accuracy was 95.1% for 36 features, and 91.1% for 18 features.

CONCLUSION

The study shows that early stages of liver fibrosis can be discriminated by the morphological features on the phase contrast images. BP network model based on combination of texture features is demonstrated effective for staging liver fibrosis.

Ultrasound or MR elastography of liver: which one shall I use?

Liver stiffness is now a well-established noninvasive biomarker for assessing fibrosis in chronic liver disease. MRI-based and ultrasound-based dynamic elastography techniques have been introduced for assessment of liver stiffness and useful in clinical staging of hepatic fibrosis. Several different elastography techniques are now available with each method having inherent strengths and limitations. The published literature generally indicates that MR elastography has a higher diagnostic performance and fewer technical failures than ultrasound-based elastography techniques in assessing hepatic fibrosis. There is also significant potential to further develop elastography techniques to implement multiparametric methods that have promise for distinguishing between processes such as inflammation, fibrosis, venous congestion, and portal hypertension that can result in increased liver stiffness. In this commentary, we compare MR and ultrasound elastography methods and their utility in clinical practice.

Ultrasound Elastography can Detect Placental Tissue Abnormalities

Background

In this prospective cohort study, we examined the utility of elastography to evaluate the fetus and placenta.

Patients and methods

Pregnant women in their third trimester of pregnancy, by which time the placenta has formed, were included in this study. A total of 111 women underwent ultrasound examinations, including elastography. Elastographic evaluation was performed using two protocols. First, the placental index (PI) was measured, which quantitatively assesses the hardness of tissue. Second, regions of interest (ROI) were categorized into 3-step scores according to the frequency of the blue area (hardness of placental tissue score [HT score]), which is a qualitative method. After delivery, 40 of the 111 placentas were pathologically examined.

Results

The average PI was 44.3 (± 29.4) in the in utero SGA group, which was significantly higher than that in the normal group (8.8 (± 10.0); p < 0.01) during pregnancy. There was a significant correlation between the PI and z score for estimated fetal weight (EFW) (r = -0.55; p < 0.01). Moreover, a significant positive correlation was observed between the PI and the z score of birth weight (r = -0.39; p < 0.01). Pathological ischemia findings of the placenta were identified in 67% of the HT score 3 group, representing 6 of the 9 patients, and in 20% of the HT score 1 group, representing only 3 of the 15 patients.

Conclusions

Placental hardness, as determined by elastography, correlates with both lower estimated fetal body weight and birth weight. These results suggest that ultrasound elastography in the placenta may be an additional marker of intrauterine fetal well-being.

Adaptive mesh refinement for elastic modulus reconstruction in elastography

Meshes play a crucial role in determining the accuracy of the elastic modulus reconstruction in the elastography when the finite element method is employed. In this article, we propose an adaptive mesh refinement strategy which can ensure the coincidence of the meshes with the shape of the inclusions in the observed tissue. This strategy is based on the intensity distribution of the strain image where the variance of the strain distribution in each element of the meshes is used to measure the homogeneity of the element, that is, the larger the strain variance is the more inhomogeneous the element will be and hence more detailed information will be included in this element. For more accurate reconstruction of such detailed information, mesh refinement procedure is implemented in such elements. Besides, two refinement steps are employed for the reconstruction to improve the fitness of the reconstructed image and the observed tissue. Simulation results show that the two-stage adaptive mesh refinement algorithm performs well without needing any prior information about the internal geometric shape in tissue. Not only Young’s moduli of models but also shapes of the inclusions can be reconstructed perfectly and quickly with our proposed method.

A Modified 2D Multiresolution Hybrid Algorithm for Ultrasound Strain Imaging

Ultrasound elastography is an imaging modality to evaluate elastic properties of soft tissue. Recently, 1D quasi-static elastography method has been commercialized by some companies. However, its performance is still limited on high strain level. In order to improve the precision of estimation during high compression, some algorithms have been proposed to expand the 1D window to a 2D window for avoiding the side-slipping. But they are usually more computationally expensive. In this paper, we proposed a modified 2D multiresolution hybrid method for displacement estimation, which can offer an efficient strain imaging with stable and accurate results. A FEM phantom with a stiffer circular inclusion is simulated for testing the algorithm. The elastographic contrast-to-noise rate (CNRe) is calculated for quantitatively comparing the performance of the proposed algorithm with conventional 1D elastography using phase zero estimation and the 1D elastography using downsampled (d-s) baseband signals. Results show that the proposed method is robust and performs similarly as other algorithms in low strain but is superior when high level strain is applied. Particularly, the CNRe of our algorithm is 15 times higher than original method under 4% strain level. Furthermore, the execution time of our algorithm is five times faster than other algorithms.

Assessment of liver fibrosis in chronic hepatitis: comparison of shear wave elastography and transient elastography

PURPOSE

To evaluate the diagnostic accuracy of shear wave elastography (SWE) and transient elastography (TE) in the evaluation of liver fibrosis in chronic hepatitis B (CHB) and C (CHC) patients taking liver biopsy as gold standard.

METHODS

Ethics committee approved this prospective cross-sectional study. Between October 2012 and December 2014, consecutive CHB/CHC patients fulfilling the inclusion criteria were included-age more than 18 years, informed written consent, willing and suitable for liver biopsy. SWE, TE, and biopsy were performed the same day. Liver stiffness measurement (LSM) cut-offs for various stages of fibrosis were generated for SWE and TE. AUC, sensitivity, specificity, and positive/negative predictive values were estimated individually or in combination.

RESULTS

CH patients (n = 240, CHB 172, CHC 68), 176 males, 64 females, mean age 32.6 ± 11.6 years were enrolled. Mean LSM of patients with no histological fibrosis (F0) was 5.0 ± 0.7 and 5.1+1.4 kPa on SWE and TE, respectively. For differentiating F2 and F3-4 fibrosis on SWE, at 7.0 kPa cut-off, the sensitivity was 81.3% and specificity 77.6%. For TE, at 8.3 kPa cut-off, sensitivity was 81.8% and specificity 83.1%. For F3 vs. F4, SWE sensitivity was 83.3% and specificity 90.7%. At 14.8 kPa cut-off, TE showed similar sensitivity (83.3%) but specificity increased to 96.5%. Significant correlation between SWE and TE was observed (r = 0.33, p < 0.001). On combining SWE and TE, a drop in sensitivity with increased specificity for all stages of liver fibrosis occured.

CONCLUSION

SWE is an accurate technique for evaluating liver fibrosis. SWE compares favorably with TE especially for predicting advanced fibrosis/cirrhosis. Combining SWE and TE further improves specificity.

Real-time elastography (RTE): a valuable sonography-based non-invasive method for the assessment of liver fibrosis in chronic hepatitis B

PURPOSE

To investigate the diagnostic usefulness of real-time elastography (RTE) for liver fibrosis in chronic hepatitis B (CHB).

METHODS

89 CHB patients were enrolled in the cross-sectional study. Ultrasound-guided percutaneous liver biopsies, RTE, and blood testing were performed in all patients. Areas under receiver operating characteristic curves (AUROC) were used to examine the diagnostic performance of liver fibrosis index (LFI) for the assessment of liver fibrosis.

RESULTS

LFI differed significantly across histologic fibrosis stages (P < 0.05), except the comparison between S0 and S1 (P = 0.298). There was a strong positive correlation between LFI and histologic liver fibrosis stage (Spearman r = 0.831, P < 0.001). The cutoff LFI value of >2.74 indicated a sensitivity of 0.766 and a specificity of 0.872 for predicting significant liver fibrosis (S ≥ 2), and the cutoff LFI value of >3.61 indicated a sensitivity of 0.833 and a specificity of 0.878 for predicting early liver cirrhosis (S = 4). LFI showed higher AUROC for discriminating significant liver fibrosis (0.873 vs. 0.614) and early liver cirrhosis (0.923 vs. 0.769) than aspartate aminotransferase-to-platelet ratio index (APRI).

CONCLUSIONS

RTE is a valuable sonography-based non-invasive method for assessment of liver fibrosis and has better discrimination power for significant liver fibrosis and early liver cirrhosis than APRI in CHB.

Comparison of laboratory tests, ultrasound, or magnetic resonance elastography to detect fibrosis in patients with nonalcoholic fatty liver disease: A meta-analysis

Many noninvasive methods for diagnosing liver fibrosis (LF) have been proposed. To determine the best method for diagnosing LF in nonalcoholic fatty liver disease (NAFLD), we conducted a systemic review and meta-analysis to compare the performance of aspartate aminotransferase to platelets ratio index (APRI), fibrosis-4 index (FIB-4), BARD score, NAFLD fibrosis score (NFS), FibroScan, shear wave elastography (SWE), and magnetic resonance elastography (MRE) for diagnosing LF in NAFLD. We compared the sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiver operating characteristic curve (AUROC) of these noninvasive methods for detecting significant fibrosis (SF), advanced fibrosis (AF), and cirrhosis. Heterogeneity was explored using meta-regression. Sixty-four articles with a total of 13,046 NAFLD subjects were included. The overall mean prevalence of SF, AF, and cirrhosis was 45.0%, 24.0%, and 9.4% in NAFLD patients, respectively. With an APRI threshold of 1.0 and 1.5, the sensitivities and specificities were 50.0% and 84.0% and 18.3% and 96.1%, respectively, for AF. With a FIB-4 threshold of 2.67 and 3.25, the sensitivities and specificities were 26.6% and 96.5% and 31.8% and 96.0%, respectively, for AF. The summary sensitivities and specificities of BARD score (threshold of 2), NFS (threshold of -1.455), FibroScan M (threshold of 8.7-9), SWE, and MRE for detecting AF were 0.76 and 0.61, 0.72 and 0.70, 0.87 and 0.79, 0.90 and 0.93, and 0.84 and 0.90, respectively. The summary AUROC values using APRI, FIB-4, BARD score, NFS, FibroScan M probe, XL probe, SWE, and MRE for diagnosing AF were 0.77, 0.84, 0.76, 0.84, 0.88, 0.85, 0.95, and 0.96, respectively.

CONCLUSION

MRE and SWE may have the highest diagnostic accuracy for staging fibrosis in NAFLD patients. Among the four noninvasive simple indexes, NFS and FIB-4 probably offer the best diagnostic performance for detecting AF. (Hepatology 2017;66:1486-1501).

Real-Time Ultrasound Elastographic Features of Primary Open Angle Glaucoma

OBJECTIVE

To investigate the significance of ultrasound elastography for evaluating the optic nerve in patients with primary open angle glaucoma (POAG).

METHODS

This prospective, comparative case series included 40 eyes of 40 patients. Twenty eyes with POAG comprised the POAG group, and 20 eyes of 20 patients without glaucoma who admitted to general eye clinic for near vision glasses comprised the control group. All real-time sonographicelastographic examinations were performed by the same physician. The ratio of orbital fat to optic nerve head (ROFON) and lateral rectus to optic nerve head (RLRON) were determined. Statistical analyses were performed using Student t test, Kolmogorov-Smirnov test, and χ test.

RESULTS

The mean ages of the patients in the study and the control groups were 65.10 ± 7.88 years (range, 48-80 years), and 69.15 ± 7.92 years (range, 55-89 years), respectively (P = 0.113). Mean ROFONs were 1.85 and 6.42 (P < 0.05), and mean RLRONs were 0.65 and 1.07 (P < 0.05) in the control and POAG groups, respectively.

CONCLUSIONS

Real-time elastography showed increased ROFON and RLRON in POAG patients. This can help to understand optic nerve head biomechanics and clarify glaucoma damage in early glaucoma cases.

Liver fibrosis diagnosis by blood test and elastography in chronic hepatitis C: agreement or combination?

BACKGROUND

In chronic hepatitis C, the European Association for the Study of the Liver and the Asociacion Latinoamericana para el Estudio del Higado recommend performing transient elastography plus a blood test to diagnose significant fibrosis; test concordance confirms the diagnosis.

AIM

To validate this rule and improve it by combining a blood test, FibroMeter (virus second generation, Echosens, Paris, France) and transient elastography (constitutive tests) into a single combined test, as suggested by the American Association for the Study of Liver Diseases and the Infectious Diseases Society of America.

METHODS

A total of 1199 patients were included in an exploratory set (HCV, n = 679) or in two validation sets (HCV ± HIV, HBV, n = 520). Accuracy was mainly evaluated by correct diagnosis rate for severe fibrosis (pathological Metavir F ≥ 3, primary outcome) by classical test scores or a fibrosis classification, reflecting Metavir staging, as a function of test concordance.

RESULTS

Score accuracy: there were no significant differences between the blood test (75.7%), elastography (79.1%) and the combined test (79.4%) (P = 0.066); the score accuracy of each test was significantly (P < 0.001) decreased in discordant vs. concordant tests. Classification accuracy: combined test accuracy (91.7%) was significantly (P < 0.001) increased vs. the blood test (84.1%) and elastography (88.2%); accuracy of each constitutive test was significantly (P < 0.001) decreased in discordant vs. concordant tests but not with combined test: 89.0 vs. 92.7% (P = 0.118). Multivariate analysis for accuracy showed an interaction between concordance and fibrosis level: in the 1% of patients with full classification discordance and severe fibrosis, non-invasive tests were unreliable. The advantage of combined test classification was confirmed in the validation sets.

CONCLUSIONS

The concordance recommendation is validated. A combined test, expressed in classification instead of score, improves this rule and validates the recommendation of a combined test, avoiding 99% of biopsies, and offering precise staging.

Improvement of Lesion Detection by Complete Angular Compound Ultrasonic Elastography

Quasi-static ultrasound elastography is an emerging diagnostic imaging modality for determining the stiffness of pathologically changed soft tissues, which do not show significant differences in acoustic impedance for B-mode imaging. Although some methods were applied to improve the signal-to-noise ratio (SNRe) and contrast-to-noise ratio (CNRe) of the constructed elastogram, nonuniform strain distribution at the internal boundary of a hard inclusion, even with the uniform displacement on the surface, is an inherent mechanical effect and results in distortion at the detected lesion boundary. To overcome such stress concentrations, a new elastographic modality was proposed, where the elastograms from different angles throughout 360° were compounded. The strain field and subsequent ultrasound images were calculated using the finite element method (FEM) and Field II, respectively, from which the elastograms were constructed. The performance of complete angular compound elastography with varied interval angles, lesion sizes, and ratios of Young's moduli of the lesion to the background was simulated and compared with that of conventional axial strain elastography. It is found that viewing the lesion from only about 10 angles (interval of 36°) would significantly improve the image quality of elastogram (increasing SNRe by at least 13% and CNRe by at least 5.8 dB), reduce the lesion distortion in the lateral direction, and enhance the sensitivity, resolution, and accuracy of lesion detection. A preliminary phantom study showed similar improvements. Altogether, complete angular compound elastography improves the elastogram quality and reduces the mechanical effects in lesion detection.

Diagnostic Accuracy of Transient Elastography for Detecting Liver Fibrosis After Liver Trannsplantation: A Specific Cut-Off Value Is Really Needed?

INTRODUCTION

Liver transplant recipients often perform liver biopsy (LB), specially in the context of potentially recurring diseases, such as hepatitis C infection. However, the LB has risks of complications, despite being the gold standard. Transient elastography (TE) is a noninvasive method comparable to the LB to evaluate liver fibrosis in various settings, but its accuracy among transplant recipients is not fully understood.

OBJECTIVE

To determine the accuracy of TE in liver transplant recipients compared with LB to successfully predict liver fibrosis.

PATIENTS AND METHODS

Patients who underwent liver transplantation at Hospital Israelita Albert Einstein from 2010 to 2012 and presented with LB indication were also subjected to TE at the time of LB. The medium value of ten successful measurements was kept as a representative of the liver stiffness. The definition of cut-off points was made to ensure specificity of ≥90 % for all fibrosis stages (F0-F4).

RESULTS

LB was performed in 267 patients. TE was not analyzed in only 8 (3 %) due to an elevated body mass index. The optimal liver stiffness cut-off value and diagnostic performance were 8.1 kPa for F ≥ 1, 12.3 kPa for F ≥ 2, 15.1 for F ≥ 3, and 16.7 for F = 4 for all patients and were 8.1 kPa for F ≥ 1, 12.3 kPa for F ≥ 2, 16.5 for F ≥ 3, and 17.6 for F = 4 for patients with hepatitis C.

CONCLUSIONS

TE demonstrated good performance in defining cut-off points for fibrosis on liver histology observed in transplant recipients. The TE can be considered an alternative to LB in post-liver transplantation.

Non-invasive diagnosis of hepatitis B virus-related cirrhosis

Chronic hepatitis B (CHB)-related cirrhosis is a major threat to public health, and about 23% of patients with CHB progress naturally to liver cirrhosis. Worldwide, about 650000 people die each year from various complications caused by CHB. liver cirrhosis has become a global concern. Progressive hepatic fibrosis can lead to cirrhosis, and early diagnosis of liver fibrosis is fundamental. Staging fibrosis is critical for the prognosis evaluation and management of patients with liver diseases. Liver biopsy is the reference standard for assessment of liver fibrosis. However, this method is invasive, and is associated with pain and complications that can be fatal, which leads to the progress of non-invasive assessment based on serological and imaging techniques. These non-invasive assessments have been shown to be effective in the diagnosis of liver fibrosis. This article mainly introduces the principle, clinical application, diagnostic efficacy, and limitations of non-invasive assessments for hepatitis B virus-related fibrosis.

Changes in liver stiffness on real-time tissue elastography before and after occlusion of spontaneous portosystemic shunts

PURPOSE

This study was conducted to evaluate changes in liver stiffness, volume, and function before and after occlusion of spontaneous portosystemic shunt.

MATERIALS & METHODS

Twenty-four patients (13 men and 11 women) with a mean age of 68.2 years±10.1 (SD) (age range, 49-82 years) underwent percutaneous occlusion of spontaneous portosystemic shunt because of gastric varices (n=17) or hepatic encephalopathy (n=7) from March 2011 to June 2013. The liver fibrosis index indicating liver stiffness was calculated by using ultrasound elastography before and after shunt occlusion. Liver volume and liver profile were also evaluated.

RESULTS

Spontaneous portosystemic shunt occlusion was uneventfully performed in all patients. The mean liver fibrosis index was significantly decreased from 2.7±1.0 before shunt occlusion to 2.0±0.9 (P<0.001) at 1 month, 2.2±1.0 at 3 months (P=0.004), and 1.6±0.7 at 6 months (P=0.001) afterwards. A significant increase in the liver volume was observed from 1035.3±340.1mL before shunt occlusion to 1116.8±298.4mL (P=0.006) at 1 month and 1174.2±354.1mL (P<0.001) at 3 months afterwards. Significant improvement in the Child-Pugh score was also found at 1 month (6.2±1.4, P<0.001), 3 months (6.5±1.1, P=0.022), and 6 months (6.0±0.9, P=0.004) after shunt occlusion as compared with that (7.2±1.9) before.

CONCLUSION

The liver stiffness decreases along with an increase in liver volume and improvement in liver function after spontaneous portosystemic shunt occlusion.

Diagnostic value of optimised real-time sonoelastography in the assessment of liver fibrosis in chronic hepatitis B and C

Aim

To optimise the method of real-time elastography (RTE) in the assessment of liver fibrosis using an in-house prepared method for elastogram analysis, as well as a semiquantitative analysis based on newly introduced parameters.

Material and methods

Sonoelastography was performed in 94 patients with various degrees of liver fibrosis and also in 25 healthy volunteers. As a reference method for diagnostic efficacy of sonoelastography-based parameters used for the assessment of fibrosis degree in patients with chronic B and C hepatitis, a liver biopsy was used. Patient’s elastograms were analysed using in-house prepared software, Pixel Count, calculating two semiquantitative parameters: mean stiffness fraction (MSF%) and intrinsic stiffness ratio (ISR).

Results

Statistically significant differences between distributions of the above presented parameters for different degrees of liver fibrosis were revealed. Indices of diagnostic efficacy for detection of significant liver fibrosis (F ≥ 2) using MSF% amounted to: sensitivity – 76%, specificity – 87% and ISR: 81% and 87%, respectively. Sensitivity of both parameters in detection of cirrhosis (F = 4) was equal to 88% and specificity amounted to: for MSF% – 84% and ISR – 86%. Interobserver reproducibility determined for both of the above parameters was high, intraclass correlation coefficients (ICC) were 0.91 for MSF% and 0.93 for ISR.

Conclusions

Real-time elastography applied in this study, using in-house prepared Pixel Count software, provided good reproducibility and diagnostic efficacy, especially specificity, in the assessment of liver fibrosis degree.