Measurement of spleen stiffness by acoustic radiation force impulse imaging identifies cirrhotic patients with esophageal varices

Shear wave elastography of the spleen: evaluation of spleen stiffness in healthy volunteers

Purpose

The aim of this study was to assess the mean value of spleen stiffness measured by Shear wave elastography in healthy patients and its dependence on age, sex, and spleen dimensions, and to evaluate the repeatability of this method.

Methods

The final study group included 59 healthy volunteers without any clinical evidence of liver disease, portal hypertension, hematological disorders, and without any pathological ultrasonographic spleen findings. Each patient underwent abdominal ultrasound examination and elastography of the liver and the spleen.

Results

The mean value of spleen stiffness was 16.6 ± 2.5 kPa. In the group of men (N = 25), it was 17.3 ± 2.7 kPa, and in the group of women (N = 34), it was 16.1 ± 2.2 kPa. The study confirmed no correlation between spleen stiffness and sex, age of patients, and spleen size. Coefficient of repeatability and correlation coefficient between the results of the first and the second measurement showed good but not ideal repeatability of the measurement results.

Conclusion

Our outcomes may be a reference point for evaluating spleen stiffness in research on patients with various illnesses.

Validation of the Baveno VI criteria to identify low risk cirrhotic patients not requiring endoscopic surveillance for varices

BACKGROUND & AIMS

The Baveno VI guidelines propose that cirrhotic patients with a liver stiffness measurement (LSM) <20kPa and a platelet count >150,000/μl can avoid screening endoscopy as their combination is highly specific for excluding clinically significant varices. The aim of the study was to validate these criteria.

METHODS

Transient elastography data was collected from two institutions from 2006-2015. Inclusion criteria were a LSM ⩾10kPa and an upper gastrointestinal endoscopy within 12months, with a diagnosis of compensated chronic liver disease. Exclusion criteria were porto-mesenteric-splenic vein thrombosis and non-cirrhotic portal hypertension. Varices were graded as low risk (grade <2) or high risk (grade ⩾2).

RESULTS

The study included 310 patients (169 (55%) hepatitis C, and 275 (89%) Child-Pugh A). Varices were present in 23% cases, with 5% prevalence of high risk varices. Overall 102/310 (33%) met the Baveno VI criteria. Within this group 11% had varices and 2% had high risk varices, representing 2/15 (13%) of all high risk varices. The Baveno VI criteria gave a sensitivity 0.87, specificity 0.34, positive predictive value 0.06, negative predictive value 0.98, positive likelihood ratio 1.31 and negative likelihood ratio 0.39. The AUROC for LSM and platelet count combined was 0.746.

CONCLUSIONS

The Baveno VI criteria performed well correctly identifying 98% of patients who could safely avoid endoscopy.

LAY SUMMARY

This study examines the effectives of a recent set of guidelines published by the Baveno VI conference, which states that patients with chronic liver disease and a low liver stiffness (<20kPa) and high platelet count (>150) are at low risk of having varices and do not need a screening endoscopy. Varices are a complication of cirrhosis, confer a risk of serious bleeding, and can be diagnosed and treated by endoscopy. Our study reviewed the clinical records of patients who have had liver stiffness scans and endoscopy over a 9-year period at two hospitals. The results show that only about 2% of patients who meet the Baveno VI criteria will be miss-classified as not having varices.

Liver and Spleen Stiffness Measurements by Point Shear Wave Elastography via Acoustic Radiation Force Impulse: Intraobserver and Interobserver Variability and Predictors of Variability in a US Population

OBJECTIVES

Measurements of liver stiffness and spleen stiffness are useful noninvasive ways to assess fibrosis and portal hypertension in patients with chronic liver disease. One method for assessing stiffness is by point shear wave elastography via acoustic radiation force impulse imaging (ARFI). Its advantage is that sites where stiffness is measured are visualized sonographically. However, its reliability has not been well established, and all studies done to date evaluating the use of ARFI in chronic liver disease have been performed outside the United States. We aimed to characterize the intraobserver and interobserver variability of ARFI-measured liver and spleen stiffness.

METHODS

Two hepatologists evaluated unselected hepatology outpatients with ARFI. Exclusions were hepatocellular carcinoma, ascites, a surgical shunt or transjugular intrahepatic portosystemic shunt, portal thrombosis, and cholestatic disease. Each operator obtained 20 measurements from the right liver lobe and spleen. Intraclass correlation coefficients (ICC) were calculated.

RESULTS

A total of 177 patients were included: median age, 61 years; 85% male; and 43% obese. Intraobserver ICCs were the same for both observers for liver stiffness (0.89; 95% confidence interval [CI], 0.85-0.92) and spleen stiffness (0.72; 95% CI, 0.61-0.80). Interobserver agreement was excellent for liver stiffness (ICC, 0.85; 95% CI, 0.76-0.90) but not as good for spleen stiffness (ICC, 0.73; 95% CI, 0.60-0.83). A body mass index of 30 kg/m² or greater, waist circumference of greater than 105 cm, and skin-to-capsule distance of 2 cm or greater negatively affected the ICC for liver stiffness; small spleen size negatively affected the ICC for spleen stiffness.

CONCLUSIONS

To our knowledge, this article is the first report of ARFI findings in a US population with chronic liver disease. Liver stiffness reproducibility was excellent, particularly in nonobese patients. Spleen stiffness reproducibility was excellent in those with larger spleens and therefore may be most useful in patients with cirrhosis and portal hypertension.

Role of spleen elastography in patients with chronic liver diseases

The development of liver cirrhosis and portal hypertension (PH), one of its major complications, are structural and functional alterations of the liver, occurring in many patients with chronic liver diseases (CLD). Actually the progressive deposition of hepatic fibrosis has a key role in the prognosis of CLD patients. The subsequent development of PH leads to its major complications, such as ascites, hepatic encephalopathy, variceal bleeding and decompensation. Liver biopsy is still considered the reference standard for the assessment of hepatic fibrosis, whereas the measurement of hepatic vein pressure gradient is the standard to ascertain the presence of PH and upper endoscopy is the method of choice to detect the presence of oesophageal varices. However, several non-invasive tests, including elastographic techniques, are currently used to evaluate the severity of liver disease and predict its prognosis. More recently, the measurement of the spleen stiffness has become particularly attractive to assess, considering the relevant role accomplished by the spleen in splanchnic circulation in the course of liver cirrhosis and in the PH. Moreover, spleen stiffness as compared with liver stiffness better represents the dynamic changes occurring in the advanced stages of cirrhosis and shows higher diagnostic performance in detecting esophageal varices. The aim of this review is to provide an exhaustive overview of the actual role of spleen stiffness measurement as assessed by several elastographic techniques in evaluating both liver disease severity and the development of cirrhosis complications, such as PH and to highlight its potential and possible limitations.

Ultrasound and Point Shear Wave Elastography in Livers of Patients with Primary Sclerosing Cholangitis

Point shear wave elastography (pSWE) is an ultrasound-based method for non-invasive quantification of liver fibrosis. The objective of this study was to explore liver pSWE in patients with primary sclerosing cholangitis (PSC) for assessment of fibrosis. Fifty-five non-transplant patients with PSC (38 males, 17 females; mean age: 46.4 y) were included and compared with 24 matched controls. Median (range) PSC duration was 8.1 (0-33) y. Ultrasonographic scanning followed by liver stiffness measurement by pSWE was performed using a conventional ultrasound system (Philips iU22). Signs of liver fibrosis on B-mode were identified in 21 patients (38%). Splenomegaly was found in 19 patients (35%) and ascites in two patients (4%). Successful pSWE measurements were achieved in the right liver lobe of all individuals and in the left liver lobe of 36 patients (65.5%). PSC patients had significantly higher median shear wave velocity (SWV) than controls in the right liver (median [range] SWV 1.26 [0.73-2.57] m/s vs. 1.09 [0.88-1.25] m/s, p < 0.001). SWV measured in the left liver lobe and spleen did not differ between PSC patients and controls. Our findings indicate that PSC patients have increased median SWV, indicating more fibrosis compared with controls; however, a wide range of SWV values were obtained among PSC patients, possibly reflecting the various stages in disease development.

Transient Elastography for Spleen Stiffness Measurement in Patients With Cirrhosis: Role in Degree of Thrombocytopenia

OBJECTIVES

The purpose of our study was to evaluate the relationship between spleen stiffness measured by transient elastography and the degree of thrombocytopenia in patients with liver cirrhosis.

METHODS

A total of 67 patients with liver cirrhosis were prospectively enrolled in the study. All patients underwent single-day hematologic and biochemical tests, sonography, and transient elastography of the liver and spleen. Thrombocytopenia was categorized as mild (platelet count, 75,000-150,000/μL), moderate (50,000-75,000/μL), and severe (<50,000/μL).

RESULTS

The degree of thrombocytopenia was significantly correlated with spleen stiffness (P = .001) and spleen size (P = .002) but not with liver stiffness (P = .086). In patients without splenomegaly, spleen stiffness values were significantly higher in patients with thrombocytopenia than in those without thrombocytopenia (P = .035). In patients with splenomegaly, spleen stiffness values were significantly higher in patients with moderate to severe thrombocytopenia than in those with a normal platelet count or mild thrombocytopenia (P = .007). Compared to liver stiffness, spleen stiffness showed a better and statistically significant correlation with platelet count and spleen size in patients with cirrhosis.

CONCLUSIONS

The degree of thrombocytopenia was directly correlated with spleen stiffness, irrespective of the presence of splenomegaly. The clinical phenomenon of unexpected thrombocytopenia may be explained by a subtle or irreversible change in spleen stiffness.

Measuring spleen stiffness to predict varices in chronic hepatitis B cirrhotic patients with or without receiving non-selective beta-blockers

OBJECTIVES

we aimed to investigate the accuracy of liver (LSM) spleen stiffness measurement (SSM) with transient elastography (TE) to predict varices in the presence of non-selective beta-blockers (NSBB).

METHODS

In this cross-sectional study of consecutive patients with chronic hepatitis B (CHB) and cirrhosis, all patients underwent TE and upper endoscopic examinations. LSM and SSM in predicting varices in patients receiving and not receiving NSBB were evaluated.

RESULTS

Altogether 144 CHB patients (29 receiving NSBB; 35 with any varices, 31 and 11 with esophageal and gastric varices, respectively) were recruited. Their mean LSM and SSM were 13.3 ± 9.0 kPa and 32.8 ± 19.2 kPa, respectively. The correlation between LSM and SSM was better in the NSBB subgroup (r = 0.525, P = 0.003) than its counterpart (r = 0.329, P  < 0.001). The area under receiver operating characteristic curve (AUROC) of LSM and SSM for any varices was 0.675 and 0.685 (P = 0.002 and 0.001), respectively. SSM of 18.9 kPa had a negative predictive value of 92.1% and negative likelihood ratio of 0.27 for ruling out any varices; and SSM of 54.9 kPa had a positive predictive value of 56.5% and a positive likelihood ratio of 4.05 to rule in varices. The AUROC of LSM for varices was 0.742 and 0.549 in patients with or without NSBB, respectively; the corresponding AUROC of SSM was 0.572 and 0.603, respectively.

CONCLUSIONS

SSM only has modest accuracy to predict varices independent of NSBB use. An SSM cutoff value of 18.9 kPa may be adopted to achieve a high negative predictive value to rule out varices.

Critical comparison of elastography methods to assess chronic liver disease

Staging of liver fibrosis and diagnosis, or exclusion, of early compensated liver cirrhosis are important in the treatment decisions and surveillance of patients with chronic liver disease. Good diagnostic accuracy, increased availability and the possibility to perform follow-up examinations led to the implementation of noninvasive methods into clinical practice. Noninvasive tests are increasingly included in national and international guidelines, leaving liver biopsy reserved for patients with unexplained discordance or suspected additional aetiologies of liver disease. In addition to staging of liver fibrosis, data on the prognostic value of these methods have increased in the past few years and are of great importance for patient care. This Review focuses on elastography methods for noninvasive assessment of liver fibrosis, disease severity and prognosis. Although liver elastography started with transient elastography, at present all large ultrasonography companies offer an elastography technique integrated in their machines. The goal of this Review is to summarize the methodological problems of noninvasive tests in general, in addition to providing an overview on currently available techniques and latest developments in liver elastography.

Non-invasive Markers of Liver Fibrosis: Adjuncts or Alternatives to Liver Biopsy?

Liver fibrosis reflects sustained liver injury often from multiple, simultaneous factors. Whilst the presence of mild fibrosis on biopsy can be a reassuring finding, the identification of advanced fibrosis is critical to the management of patients with chronic liver disease. This necessity has lead to a reliance on liver biopsy which itself is an imperfect test and poorly accepted by patients. The development of robust tools to non-invasively assess liver fibrosis has dramatically enhanced clinical decision making in patients with chronic liver disease, allowing a rapid and informed judgment of disease stage and prognosis. Should a liver biopsy be required, the appropriateness is clearer and the diagnostic yield is greater with the use of these adjuncts. While a number of non-invasive liver fibrosis markers are now used in routine practice, a steady stream of innovative approaches exists. With improvement in the reliability, reproducibility and feasibility of these markers, their potential role in disease management is increasing. Moreover, their adoption into clinical trials as outcome measures reflects their validity and dynamic nature. This review will summarize and appraise the current and novel non-invasive markers of liver fibrosis, both blood and imaging based, and look at their prospective application in everyday clinical care.

Shear Wave Elastography of the Spleen for Monitoring Transjugular Intrahepatic Portosystemic Shunt Function: A Pilot Study

OBJECTIVES

To assess the feasibility of splenic shear wave elastography in monitoring transjugular intrahepatic portosystemic shunt (TIPS) function.

METHODS

We measured splenic shear wave velocity (SWV), main portal vein velocity (PVV), and splenic vein velocity (SVV) in 33 patients 1 day before and 3 days to 12 months after TIPS placement. We also measured PVV, SVV, and SWV in 10 of 33 patients with TIPS dysfunction 1 day before and 3 to 6 days after TIPS revision. Analyses included differences in portosystemic pressure gradient (PPG), PVV, SVV, and mean SWV before and after TIPS procedures; comparison of median SWV before and after TIPS procedures; differences in PVV, SVV, and SWV before and at different times up to 12 months after TIPS placement; accuracy of PVV, SVV, and SWV in determining TIPS dysfunction; and correlation between PPG and SWV.

RESULTS

During 12 months of follow-up, 23 of 33 patients had functioning TIPS, and 10 had TIPS dysfunction. The median SWV was significantly different before and after primary TIPS placement (3.60 versus 3.05 m/s; P = .005), as well as before and after revision (3.73 versus 3.06 m/s; P = .003). The PPG, PVV, and SVV were also significantly different before and after TIPS placement and revision (P < .001). The PPG and SWV decreased, whereas PVV and SVV increased, after successful TIPS procedures. A positive correlation was observed between PPG and SWV (r = 0.70; P < .001), and a negative correlation was observed between PPG and PVV and SVV (r = -0.65; P < .001). The areas under the receiver operating characteristic curve for PVV, SVV, and SWV in determining TIPS dysfunction were 0.82, 0.84, and 0.81, respectively.

CONCLUSIONS

Splenic SWV is compatible with splenoportal venous velocity in quantitatively monitoring TIPS function and determining TIPS dysfunction.

Liver stiffness plus platelet count can be used to exclude high-risk oesophageal varices

BACKGROUND/AIMS

Endoscopic screening for high-risk gastro-oesophageal varices (GOV) is recommended for compensated cirrhotic patients with transient elastography identifying increasing numbers of patients with cirrhosis without portal hypertension. Using liver stiffness measurement (LSM) ± platelet count, the aim was to develop a simple clinical rule to exclude the presence of high-risk GOV in patients with Child-Pugh A cirrhosis.

METHODS

A retrospective analysis of 71 patients with Child-Pugh A cirrhosis diagnosed by transient elastography (LSM >13.6 kPa) who underwent screening gastroscopy was conducted. A predictive model using LSM ± platelet count was assessed to exclude the presence of high-risk GOV (diameter >5 mm and/or the presence of high-risk stigmata) and validated using a second cohort of 200 patients from two independent centres.

RESULTS

High-risk GOV were present in 10 (15%) and 16 (8%) of the training and validation cohorts, respectively, which was associated with LSM and Pl count (P < 0.05). A combined model based on LSM and Pl count was more accurate for excluding the presence of high-risk GOV than either alone (training cohort AUROC: 0.87 [0.77-0.96] vs. 0.78 [0.65-0.92] for LSM and 0.71 [0.52-0.90] for platelets) with the combination of LSM ≤25 kPa and Pl ≥100 having a NPV of 100% in both the training and validation cohorts. A total of 107 (39%) patients meet this criterion.

CONCLUSION

The combination of LSM ≤25 kPa and Pl ≥100 can be used in clinical practice to exclude the presence of high-risk GOV in patients with Child-Pugh A cirrhosis.

Facility- and Patient-Level Factors Associated with Esophageal Variceal Screening in the USA

BACKGROUND AND AIM

The American Association for the Study of Liver Disease (AASLD) recommends screening for esophageal varices (EV) by esophagoduodenoscopy (EGD) in patients with cirrhosis to guide decisions regarding primary prophylaxis for EV hemorrhage. We aimed to identify patient and facility factors associated with EV screening in veterans with hepatitis C (HCV)-associated cirrhosis.

METHODS

This was a population-based cohort study. Veterans with HCV and newly diagnosed cirrhosis between 1/1/2004 and 12/31/2005 and followed until 12/31/2011 were included. The primary outcome was receipt of EGD within 1 year of cirrhosis diagnosis. Patient- and facility-level factors associated with EV screening were determined.

RESULTS

A total of 4230 patients with HCV cirrhosis were identified. During median follow-up of 6.1 years (IQR: 4.0-8.0), 21.5 % developed a decompensating event, and 38.3 % died. Fifty-four percent received an EGD, and 33.8 % had an EGD within guidelines. Median time from cirrhosis diagnosis to EGD was 72 days (IQR: 12-176). Factors independently associated with receipt of EV screening were a decompensation event (OR 1.16, CI 1.01-1.32) and gastroenterology/hepatology clinic access (OR 2.1, CI 1.73-2.46), whereas cardiovascular (OR 0.81, CI 0.69-0.95), mental health (OR 0.79, CI 0.68-0.91), and respiratory (OR 0.85, CI 0.72-0.99) comorbidities were associated with reduced likelihood of EV screening.

CONCLUSION

EV screening per AASLD guidelines occurs in only one-third of patients. This missed opportunity was strongly associated with access to gastroenterology/hepatology specialty care. Additionally, providers may be relying on clinical cues (i.e., decompensation) to prompt referral for endoscopy suggesting education to improve compliance with guidelines is needed.

Simultaneous measurement of hepatic and splenic stiffness using MR elastography: preliminary experience

PURPOSE

To compare MR elastography (MRE) using a single and a dual driver excitation for the quantification of hepatic and splenic stiffness (HS and SS), and to investigate the performance of HS and SS measured with single or dual driver excitation for the detection of liver cirrhosis in subjects with liver disease.

PATIENTS AND METHODS

This prospective HIPAA compliant and IRB approved study involved 49 subjects who underwent MRE at 3.0T, comparing three different acquisition methods (single driver on the liver, single driver on the spleen and dual driver acoustic excitation). A Mann-Whitney test was used to assess changes in stiffness values. Bland-Altman analysis was used to compare single and dual driver configurations for each organ. Performance for detection of liver cirrhosis was assessed using ROC analysis. Pearson correlation was used to estimate the dependence of HS and SS on spleen size.

RESULTS

There were 40 noncirrhotic and 9 cirrhotic patients. There was good agreement between stiffness values measured with a single or a dual driver (Bland-Altman limits of agreement -14.3 % to 18.9 % and -18.1 % to 29.7 %, CV 6.4 % and 9.4 %, for HS and SS. respectively). HS and SS were higher in subjects with liver cirrhosis (p < 0.001), with excellent detection performance (AUROC range 0.87-0.93). SS correlated strongly with spleen size (r = 0.69, p < 0.001), while HS showed weak correlation (r = 0.38, p = 0.006).

CONCLUSION

Using a dual acoustic driver configuration, hepatic and splenic stiffness can be simultaneously estimated with good concordance with single driver measurement.

Portal Hypertension in Patients with Liver Cirrhosis: Diagnostic Accuracy of Spleen Stiffness

PURPOSE

To evaluate the accuracy of spleen stiffness (SS) and liver stiffness (LS) measured by using acoustic radiation force impulse imaging in the diagnosis of portal hypertension in patients with liver cirrhosis, with the hepatic venous pressure gradient (HVPG) as a reference standard.

MATERIALS AND METHODS

Institutional review board approval and informed consent were obtained for this prospective single-center study. From February 2012 to August 2013, 60 patients with liver cirrhosis (mean age, 70.8 years; age range, 34-88 years; 34 men, 26 women) with HVPG, LS, and SS measurements and gastrointestinal endoscopy and laboratory data were included if they met the following criteria: no recent episodes of gastrointestinal bleeding, no history of splenectomy, no history of partial splenic embolization, no history of β-blocker therapy, and absence of portal thrombosis. The efficacy of the parameters for the evaluation of portal hypertension was analyzed by using the Spearman rank-order correlation coefficient and receiver operating characteristic (ROC) curve analysis.

RESULTS

The correlation coefficient between SS and HVPG (r = 0.876) was significantly better than that between LS and HVPG (r = 0.609, P < .0001). The areas under the ROC curve of SS for the identification of clinically important portal hypertension (HVPG ≥ 10 mm Hg), severe portal hypertension (HVPG ≥ 12 mm Hg), esophageal varices (EVs), and high-risk EVs were significantly higher (0.943, 0.963, 0.937, and 0.955, respectively) than those of LS, spleen diameter, platelet count, and platelet count to spleen diameter ratio (P < .05 for all). SS could be used to accurately rule out the presence of clinically important portal hypertension, severe portal hypertension, EVs, and high-risk EVs (negative likelihood ratios, 0.051, 0.056, 0.054, and 0.074, respectively).

CONCLUSION

SS is reliable and has better diagnostic performance than LS for identifying portal hypertension in liver cirrhosis.

Interplatform reproducibility of liver and spleen stiffness measured with MR elastography

PURPOSE

To assess interplatform reproducibility of liver stiffness (LS) and spleen stiffness (SS) measured with magnetic resonance elastography (MRE) based on a 2D gradient echo (GRE) sequence.

MATERIALS AND METHODS

This prospective Health Insurance Portability and Accountability Act (HIPAA)-compliant and Institutional Review Board (IRB)-approved study involved 12 subjects (five healthy volunteers and seven patients with liver disease). A multislice 2D-GRE-based MRE sequence was performed using two systems from different vendors (3.0T GE and 1.5T Siemens) on the same day. Two independent observers measured LS and SS on confidence maps. Bland-Altman analysis (with coefficient of reproducibility, CR), coefficient of variability (CV), and intraclass correlation (ICC) were used to analyze interplatform, intra- and interobserver variability. Human data were validated using a gelatin-based phantom.

RESULTS

There was excellent reproducibility of phantom stiffness measurement (CV 4.4%). Mean LS values were 3.44-3.48 kPa and 3.62-3.63 kPa, and mean SS values were 7.54-7.91 kPa and 8.40-8.85 kPa at 3.0T and 1.5T for observers 1 and 2, respectively. The mean CVs between platforms were 9.2%-11.5% and 13.1%-14.4% for LS and SS, respectively, for observers 1 and 2. There was excellent interplatform reproducibility (ICC >0.88 and CR <36.2%) for both LS and SS, and excellent intra- and interobserver reproducibility (intraobserver: ICC >0.99, CV <2.1%, CR <6.6%; interobserver: ICC >0.97, CV and CR <16%).

CONCLUSION

This study demonstrates that 2D-GRE MRE provides platform- and observer-independent LS and SS measurements.

Personalized management of cirrhosis by non-invasive tests of liver fibrosis

Owing to the high prevalence of various chronic liver diseases, cirrhosis is one of the leading causes of morbidity and mortality worldwide. In recent years, the development of non-invasive tests of fibrosis allows accurate diagnosis of cirrhosis and reduces the need for liver biopsy. In this review, we discuss the application of these non-invasive tests beyond the diagnosis of cirrhosis. In particular, their role in the selection of patients for hepatocellular carcinoma surveillance and varices screening is highlighted.

Liver Cirrhosis: Evaluation, Nutritional Status, and Prognosis

The liver is the major organ for the metabolism of three major nutrients: protein, fat, and carbohydrate. Chronic hepatitis C virus infection is the major cause of chronic liver disease. Liver cirrhosis (LC) results from different mechanisms of liver injury that lead to necroinflammation and fibrosis. LC has been seen to be not a single disease entity but one that can be graded into distinct clinical stages related to clinical outcome. Several noninvasive methods have been developed for assessing liver fibrosis and these methods have been used for predicting prognosis in patients with LC. On the other hand, subjects with LC often have protein-energy malnutrition (PEM) and poor physical activity. These conditions often result in sarcopenia, which is the loss of skeletal muscle volume and increased muscle weakness. Recent studies have demonstrated that PEM and sarcopenia are predictive factors for poorer survival in patients with LC. Based on these backgrounds, several methods for evaluating nutritional status in patients with chronic liver disease have been developed and they have been preferably used in the clinical field practice. In this review, we will summarize the current knowledge in the field of LC from the viewpoints of diagnostic method, nutritional status, and clinical outcomes.

Liver and spleen transient elastography and Acoustic Radiation Force Impulse Measurements. Performance and comparison of measurements in the same area concurrently assessed for liver fibrosis by biopsy

PURPOSE

The estimation of the degree of liver fibrosis is important for prognosis, surveillance, and treatment of chronic liver disease. Although liver biopsy is the gold standard for diagnosis, it is subject to sampling error, while ultrasound-based techniques, such as Acoustic Radiation Force Impulse (ARFI) and transient elastography, have gained popularity. However, no previous comparative study has performed these ultrasound techniques at the time of biopsy. The aim of this study was to compare the reliability of these techniques to define the severity of liver fibrosis in viral hepatitis patients.

PATIENTS AND METHODS

We compared liver transient elastography and Acoustic Radiation Force Impulse measurements, performed along the intended biopsy track, with liver biopsy results in 46 viral hepatitis patients, all measured on the same morning. Fibrosis was measured by histology using the Ishak fibrosis staging.

RESULTS

The relative sensitivity and specificity of different incremental cut-off values for both techniques, and the predictive ability of pairwise comparison of the 3 tests (including APRI) and of their combined use with more severe grades of histology-measured liver fibrosis, show that the single variable with greatest sensitivity and specificity is TE with a cut-off of >10.0.

CONCLUSION

Transient elastography has a better performance than ARFI, which has a lower sensitivity, in the diagnosis of severe stages of fibrosis. Also ARFI of the spleen is correlated with Ishak fibrosis staging, and could be a possible additional tool for the diagnosis of liver fibrosis.

Liver and spleen stiffness and other noninvasive methods to assess portal hypertension in cirrhotic patients: a review of the literature

Portal hypertension (PH) is one of the most important causes of morbidity and mortality in patients with chronic liver disease. PH measurement is crucial to stage and predict the clinical outcome of liver cirrhosis. Measurement of hepatic vein pressure gradient is considered the gold standard for assessment of the degree of PH; however, it is an invasive method and has not been used widely. Thus, noninvasive methods have been proposed recently. We critically evaluated serum markers, abdominal ultrasonography, and particularly liver and spleen stiffness measurement, which represent the more promising methods to stage PH degree and to assess the presence/absence of esophageal varices (EV). A literature search was carried out on MEDLINE, EMBASE, Web of Science, and Scopus for articles and abstracts. The search terms used included 'liver cirrhosis', 'portal hypertension', 'liver stiffness', 'spleen stiffness', 'ultrasonography', and 'portal hypertension serum biomarker'. The articles cited were selected on the basis of their relevance to the objective of the review. The results of available studies indicate that individually, these methods have a mild accuracy in predicting the presence of EV, and thus they cannot substitute endoscopy to predict EV. When these tests were used in combination, their accuracy increased. In addition to the PH staging, several serum markers and spleen stiffness measurement can predict the clinical outcome of liver cirrhosis with a good accuracy, comparable to that of hepatic vein pressure gradient. In the future, noninvasive methods could be used to select patients requiring further investigations to identify the best tailored clinical management.

Liver and spleen elastography using supersonic shear imaging for the non-invasive diagnosis of cirrhosis severity and oesophageal varices

BACKGROUND

Elastography is a promising non-invasive approach for assessing liver fibrosis. We assessed diagnostic performances of liver and spleen stiffness using supersonic shear imaging for diagnosing cirrhosis severity and oesophageal varices.

METHODS

401 consecutive cirrhotic patients were prospectively enrolled from November 2012 to March 2014. All patients underwent liver and spleen stiffness measurement with supersonic shear imaging and Fibroscan.

RESULTS

Failures of measurement were 6.2% and 29.2% for liver and spleen stiffness (supersonic shear imaging), and 18.4% for liver stiffness (Fibroscan). Liver and spleen stiffness were correlated with severity of cirrhosis, with values increasing according to Child-Pugh subclasses and presence of complications. With a negative predictive value ≥90%, liver stiffness cut-offs for high-risk oesophageal varices, history of ascites, Child-Pugh B/C, variceal bleeding and clinical decompensation were 12.8, 19, 21.4, 30.5, and 39.4 kPa, respectively. Areas under the curve of spleen and liver stiffness (supersonic shear imaging), and liver stiffness (Fibroscan) were 0.80, 0.77 and 0.73 respectively for detection of oesophageal varices.

CONCLUSION

Liver stiffness using supersonic shear imaging is a relevant diagnostic tool for assessing cirrhosis severity and its complications. Spleen stiffness shows promising results for the detection of oesophageal varices but is not yet sufficiently robust for clinical practice owing to high failure rates.

Elastography Assessment of Liver Fibrosis: Society of Radiologists in Ultrasound Consensus Conference Statement

The Society of Radiologists in Ultrasound convened a panel of specialists from radiology, hepatology, pathology, and basic science and physics to arrive at a consensus regarding the use of elastography in the assessment of liver fibrosis in chronic liver disease. The panel met in Denver, Colo, on October 21-22, 2014, and drafted this consensus statement. The recommendations in this statement are based on analysis of current literature and common practice strategies and are thought to represent a reasonable approach to the noninvasive assessment of diffuse liver fibrosis.

The Role of Spleen Stiffness in Determining the Severity and Bleeding Risk of Esophageal Varices in Cirrhotic Patients

Esophageal varix and its hemorrhage are serious complications of liver cirrhosis. Recent studies have focused on noninvasive prediction of esophageal varices. We attempted to evaluate the association of liver and spleen stiffness (LS and SS) as measured by acoustic radiation force impulse imaging, with the presence and severity of esophageal varices and variceal hemorrhage in cirrhotic patients. We measured LS and SS, along with endoscopic examination of esophageal varices for a total of 125 cirrhotic patients at a single referral hospital in this prospective observational study. The diagnostic utility of noninvasive methods for identifying varices and their bleeding risk was compared, including LS, SS, spleen length, Child-Pugh score, and various serum fibrosis indices. Esophageal varices were present in 77 patients (61.6%). SS was significantly higher in patients with varices than in those without varices (3.58 ± 0.47 vs 3.02 ± 0.49; P < 0.001). A tendency toward increasing SS levels was observed with increasing severity of varices (no varix, 3.02 ± 0.49; F1, 3.39 ± 0.51; F2, 3.60 ± 0.42; F3, 3.85 ± 0.37; P < 0.001). SS was significantly higher in patients who experienced variceal hemorrhage than in those who did not (3.80 ± 0.36 vs 3.20 ± 0.51; P = 0.002). An optimal cut-off value of SS for high-risk varices (≥ F2) or variceal hemorrhage was 3.40 m/s. SS was significantly correlated with the presence, severity, and bleeding risk of esophageal varices. Prompt endoscopic evaluation of variceal status and prophylactic measures based on the SS may be warranted for cirrhotic patients.

WFUMB guidelines and recommendations for clinical use of ultrasound elastography: Part 3: liver

The World Federation for Ultrasound in Medicine and Biology (WFUMB) has produced these guidelines for the use of elastography techniques in liver disease. For each available technique, the reproducibility, results, and limitations are analyzed, and recommendations are given. Finally, recommendations based on the international literature and the findings of the WFUMB expert group are established as answers to common questions. The document has a clinical perspective and is aimed at assessing the usefulness of elastography in the management of liver diseases.

Liver and spleen stiffness and their ratio assessed by real-time two dimensional-shear wave elastography in patients with liver fibrosis and cirrhosis due to chronic viral hepatitis

OBJECTIVES

To investigate the performance of real-time 2D shear wave elastography (RT 2D-SWE) for non-invasive staging of liver disease in patients with chronic viral hepatitis (CVH).

MATERIALS AND METHODS

Naive CVH patients underwent liver (LS) and spleen stiffness (SS) measurements by an intercostal approach. Patients with ALT >3× upper limit of normal, cholestasis as revealed by dilated intrahepatic biliary tree, and liver congestion were excluded. Results were expressed in kPa and compared to histological stage (Ishak) of liver fibrosis (LF). Patients with decompensated liver cirrhosis (LC) were diagnosed using standard clinical, ultrasound, and endoscopic criteria.

RESULTS

Of 123 patients, LS was successfully measured in 79.7% and SS in 53.7%. LS accurately differentiated between liver disease stages, with cut-off values of 8.1 (AUC 0.991) for F ≥ 3, 10.8 kPa (AUC 0.954) for F ≥ 5, and 27 kPa (AUC 0.961) for decompensated LC. SS was significantly different between non-cirrhotic stages (F0-4) and LC (cut-off 24 kPa; AUC 0.821). While both LS and SS increased with liver disease progression, the difference between them decreased, as reflected by the stiffness ratio index.

CONCLUSIONS

RT 2D-SWE can accurately differentiate between the stages of LF, and can distinguish LF from LC and compensated from decompensated LC.

KEY POINTS

• RT 2D-SWE is an accurate method for assessment of liver fibrosis. • RT 2D-SWE is applicable in 80% of patients with chronic viral hepatitis. • RT 2D-SWE accurately differentiates compensated from decompensated liver cirrhosis. • Both liver and spleen stiffness increase with progression of liver fibrosis. • In cirrhosis, the difference between liver and spleen stiffness decreases.

The degree of spleen stiffness measured on acoustic radiation force impulse elastography predicts the severity of portal hypertension in patients with biliary atresia after portoenterostomy

BACKGROUND/PURPOSE

Acoustic radiation focus impulse (ARFI) elastography is a new method for assessing the degree of tissue stiffness. We herein evaluated the degree of spleen stiffness (SS) using ARFI elastography in patients with biliary atresia (BA) after Kasai portoenterostomy (KPE).

METHODS

We retrospectively collected the liver stiffness (LS) and SS values on ARFI elastography from 43 patients undergoing KPE between September 2010 and November 2013. We analyzed the correlations between these values and variables related to the severity of liver dysfunction and portal hypertension (PHT). The data were expressed as the standard deviation score (z-score) relative to the previously reported normal values for the patient's age.

RESULTS

The SS value was significantly associated with the spleen diameter and development of collateral vessels, in comparison to the LS value. Interestingly, there was a significant correlation between SS value and the portal vein (PV) diameter. Thirty patients (69.8%) consequently underwent LT; these patients showed higher SS values and smaller PV diameters than the patients monitored without LT.

CONCLUSIONS

The degree of SS measured on ARFI elastography can be used to predict the severity of PHT in BA patients after KPE.

A novel model to predict esophageal varices in patients with compensated cirrhosis using acoustic radiation force impulse elastography

Background & Aims

Few noninvasive methods can accurately identify esophageal varices (EVs) in patients with compensated cirrhosis. We developed and validated a novel, acoustic radiation force impulse (ARFI) elastography-based prediction model for high-risk EVs (HEVs) in patients with compensated cirrhosis.

Methods

A total of 143 patients with compensated cirrhosis between February, 2010 and February, 2013 (training set) and 148 between June, 2010 and May, 2013 (validation set) who underwent ARFI elastography and endoscopy were prospectively recruited. Independent predictors of HEVs were used to construct a prediction model.

Results

Based on multivariate analysis, we developed two new statistical models, a varices risk score and ARFI-spleen diameter-to-platelet ratio score (ASPS), the latter of which was calculated as ARFI velocity × spleen diameter/platelet count. The area under receiver operating characteristic curve (AUROC) of the varices risk score and ASPS to predict HEVs were 0.935 (95% confidence interval [CI] 0.882–0.970) and 0.946 (95% CI 0.895–0.977), respectively. When ASPS, a simpler model with a higher AUROC, was applied in the validation set, acceptable diagnostic accuracy for HEVs was observed (AUROC = 0.814 [95% CI 0.743–0.885]). To detect HEVs, a negative predictive value of 98.3% was achieved at ASPS <2.83, whereas a positive predictive value of 100% was achieved at ASPS >5.28.

Conclusions

ASPS, a novel noninvasive ARFI-based prediction model, can accurately identify HEVs in patients with compensated cirrhosis. ASPS <2.83 may safely rule out the presence of HEVs, whereas patients with ASPS >5.28 should be considered for endoscopic examinations or appropriate prophylactic treatment.

Severe liver fibrosis caused by Schistosoma mansoni: management and treatment with a transjugular intrahepatic portosystemic shunt

Liver diseases are common in inhabitants and migrants of tropical countries, where the liver can be exposed not only to toxins but also to many viral, bacterial, fungal, and parasitic infections. Schistosomiasis--a common parasitic infection that affects at least 240 million people worldwide, mostly in Africa--is regarded as the most frequent cause of liver fibrosis worldwide. We present a case of a 19-year-old male refugee from Guinea with recurrent oesophageal variceal bleeding due to schistosomal liver fibrosis refractory to endoscopic therapy. This case was an indication for portosystemic surgery, which is a highly invasive non-reversible intervention. An alternative, less invasive, reversible radiological procedure, used in liver cirrhosis, is the placement of a transjugular intrahepatic portosystemic shunt (TIPS). After thorough considerations of all therapeutic options we placed a TIPS in our patient. In more than 3 years of observation, he is clinically well apart from one episode of hepatic encephalopathy related to an acute episode of viral gastroenteritis. Bleeding from oesophageal varices has not recurred. In this Grand Round, we review the diagnostic approaches and treatment options for portal hypertension due to schistosomal liver fibrosis.

New imaging techniques for liver diseases

Newly developed or advanced methods of ultrasonography and MR imaging provide combined anatomical and quantitative functional information about diffuse and focal liver diseases. Ultrasound elastography has a central role for staging liver fibrosis and an increasing role in grading portal hypertension; dynamic contrast-enhanced ultrasonography may improve tumor characterization. In clinical practice, MR imaging examinations currently include diffusion-weighted and dynamic MR imaging, enhanced with extracellular or hepatobiliary contrast agents. Moreover, quantitative parameters obtained with diffusion-weighted MR imaging, dynamic contrast-enhanced MR imaging and MR elastography have the potential to characterize further diffuse and focal liver diseases, by adding information about tissue cellularity, perfusion, hepatocyte transport function and visco-elasticity. The multiparametric capability of ultrasonography and more markedly of MR imaging gives the opportunity for high diagnostic performance by combining imaging biomarkers. However, image acquisition and post-processing methods should be further standardized and validated in multicenter trials.

Spleen stiffness can non-invasively assess resolution of portal hypertension after liver transplantation

BACKGROUND & AIMS

Spleen stiffness can be measured by transient elastography. Recent studies have shown that spleen stiffness correlates with hepatic venous pressure gradient and can predict oesophageal varices. Elevated spleen stiffness in cirrhosis has been attributed to splenic tissue hyperplasia and fibrosis, portal hypertension and its consequent hyperdynamic circulation. The aim of this study was to investigate changes to spleen stiffness after orthotopic liver transplantation (OLT) when portal hypertension resolves.

METHODS

Twenty-one patients awaiting OLT were studied prospectively, while 11 post-transplant patients were recruited as controls. Spleen and liver stiffness were measured with Fibroscan before and at 2-8 weeks after OLT. Criteria applied for spleen stiffness measurement were similar to liver stiffness (≥10 measurements; ≥60% success rate; interquartile range, IQR <30% of median).

RESULTS

Spleen stiffness was significantly higher before OLT compared to post-transplant patients [75.0 (63.9-75.0) kPa vs. 28.4 (22.0-37.5) kPa; P < 0.0001]. For patients awaiting OLT, 90% (19/21) had oesophageal varices (endoscopically or radiologically). In patients who underwent liver transplantation, spleen stiffness decreased significantly from a median of 75.0 (62.0-75.0) kPa before OLT, to 41.9 (27.0-47.4) kPa at 2 weeks after transplant and 32.9 (29.1-38.0) kPa in the subsequent 4-8 weeks after OLT (P < 0.0001). As expected, liver stiffness measurements reduced from 39.3 (24.9-75.0) kPa to 8.6 (6.8-11.8) kPa in patients receiving OLT (P = 0.0004).

CONCLUSIONS

Spleen stiffness can non-invasively assess changes in portal pressure after liver transplantation and decreases significantly when portal hypertension resolves.

Factors that influence kidney shear wave speed assessed by acoustic radiation force impulse elastography in patients without kidney pathology

Our aim was to assess kidney shear wave speed by means of acoustic radiation force impulse (ARFI) elastography in patients without kidney pathology ("normal" patients) and to identify the factors that influence it. We analyzed 91 "normal" patients in whom kidney shear wave speed was assessed by means of ARFI elastography. Five valid ARFI elastographic measurements were obtained in all "normal" patients in both kidneys. In univariate analysis, age (r = -0.370, p = 0.003), gender (female vs. male, r = -0.305, p = 0.003) and measurement depth (r = -0.285, p = 0.01) were significantly correlated with kidney shear wave speed values assessed by ARFI elastography, whereas body mass index, kidney length and renal parenchyma thickness were not correlated. In multivariate analysis, only age (p = 0.006) and gender (p = 0.03) were significantly correlated with kidney shear wave speed values. In conclusion, kidney shear wave speed values assessed by ARFI elastography in "normal" patients are influenced mainly by age and gender and less by measurement depth.

Serum Liver Fibrosis Markers for Predicting the Presence of Gastroesophageal Varices in Liver Cirrhosis: A Retrospective Cross-Sectional Study

Background and Aims. A retrospective cross-sectional study was conducted to evaluate the role of hyaluronic acid (HA), laminin (LN), amino-terminal propeptide of type III procollagen (PIIINP), and collagen IV (CIV) in predicting the presence of gastroesophageal varices (GEVs) in patients with liver cirrhosis. Methods. We enrolled 118 patients with liver cirrhosis who underwent the tests for the four serum liver fibrosis markers and upper gastrointestinal endoscopy at the same admissions. The predictive values of the four serum liver fibrosis markers were evaluated by the areas under the receiving operator characteristics curves (AUROCs) with 95% confidence intervals (CIs). Results. The prevalence of GEVs was 88% (104/118). The AUROCs for HA, LN, PIIINP, and CIV levels in predicting the presence of GEVs were 0.553 (95% CI: 0.458 to 0.644, P = 0.5668), 0.490 (95% CI: 0.397 to 0.584, P = 0.9065), 0.622 (95% CI: 0.528 to 0.710, P = 0.1099), and 0.560 (95% CI: 0.466 to 0.652, P = 0.4909). The PIIINP level at a cut-off value of 31.25 had a sensitivity of 73.1% and a specificity of 57.1%. Conclusions. The present study did not recommend HA, LN, PIIINP, and CIV levels to evaluate the presence of GEVs in liver cirrhosis.

Epidemiology, diagnosis and early patient management of esophagogastric hemorrhage

Acute variceal bleeding (AVB) is a potentially life-threatening complication of cirrhosis and portal hypertension. Combination therapy with vasoactive drugs and endoscopic variceal ligation is the first-line treatment in the management of AVB after adequate hemodynamic resuscitation. Short-term antibiotic prophylaxis, early resuscitation, early use of lactulose for prevention of hepatic encephalopathy, targeting of conservative goals for blood transfusion, and application of early transjugular intrahepatic portosystemic shunts in patients with AVB have further improved the prognosis of AVB. This article discusses the epidemiology, diagnosis, and nonendoscopic management of AVB.

Prospective comparison of spleen and liver stiffness by using shear-wave and transient elastography for detection of portal hypertension in cirrhosis

PURPOSE

To prospectively compare the technical success rate and accuracy of shear-wave elastography (SWE) and transient elastography (TE) for the detection of clinically significant portal hypertension (PH) in patients with advanced cirrhosis who are undergoing hepatic vein pressure gradient (HVPG) measurements.

MATERIALS AND METHODS

The institutional ethics committee approved the study, and written informed consent was obtained. Seventy-nine consecutive patients with cirrhosis who were undergoing SWE and TE at the time of HVPG measurement were studied. The technical success rate of SWE and TE was compared with the diagnostic value of liver stiffness (LS) and spleen stiffness (SS) measurements and composite scores (LS spleen-diameter-to-platelet-ratio score [LSPS] and PH risk score) by using SWE and TE to detect clinically significant PH (HVPG ≥ 10 mm Hg) and esophageal varices at high risk of bleeding. Areas under the receiver operating characteristic curve and the DeLong test were used.

RESULTS

The technical success rate of SWE was significantly better than that of TE for both LS and SS (97% and 97% vs 44% and 42%, respectively; P < .001). LS of more than 24.6 kPa with SWE had a sensitivity, specificity, and accuracy for clinically significant PH of 81%, 88%, and 82%, respectively. Diagnostic performance of LS by using SWE was significantly better than that for SS for the diagnosis of clinically significant PH (area under the receiver operating characteristic curve of 0.87 vs 0.64, P = .003). LS, SS, LSPS, and PH risk score (according to SWE or TE) did not differ between patients with and those without high-risk esophageal varices (P = .09-.42).

CONCLUSION

In patients with advanced cirrhosis who are undergoing HVPG measurements, LS measurements obtained by using SWE have a higher technical success rate and a better diagnostic value than TE for clinically significant PH.

Evaluation of Liver Stiffness After Radioembolization by Real-Time ShearWave™ Elastography: Preliminary Study

PURPOSE

To evaluate the effect of ShearWave(™) elastography (SWE) for the assessment of liver fibrosis after radioembolization (RE) in patients with liver malignancies.

MATERIALS AND METHODS

We prospectively examined the effects of SWE before and after RE in 17 adult patients, from June 2012 to September 2013. All patients underwent SWE within 1 month before and 3 months (96.3 ± 22.9 days) after RE. Measurements were taken in segments III, IV, V, and VI (lateral/medial left lobe and anterior/posterior right lobe, respectively). Liver stiffness was studied in the 39 treated segments.

RESULTS

The mean stiffness of liver tissue according to the pre-RE SWE measurements was not different from the post-RE SWE measurements in the segments that did not undergo RE. Conversely, segments treated with RE were significantly stiffer according to the post-RE SWE measurements (mean SWE 17.4 kPa) than according to the baseline measurements (7.0 kPa) (p < 0.001). Patients with hepatocellular carcinoma and preexisting infection with hepatitis B and C viruses had higher pre-embolization stiffness, and the post-embolization stiffness of the treated segments in these patients was higher than that in the remainder of the study population.

CONCLUSION

These data suggest that SWE measurements of liver stiffness increase as early as the third month after RE. SWE could be used as a noninvasive complementary imaging method for preliminary assessment of liver fibrosis before and after RE.

Non-invasive assessment of liver fibrosis in chronic hepatitis B

The goal of this review is to provide a comprehensive picture of the role, clinical applications and future perspectives of the most widely used non-invasive techniques for the evaluation of hepatitis B virus (HBV) infection. During the past decade many non-invasive methods have been developed to reduce the need for liver biopsy in staging fibrosis and to overcome whenever possible its limitations, mainly: invasiveness, costs, low reproducibility, poor acceptance by patients. Elastographic techniques conceived to assess liver stiffness, in particular transient elastography, and the most commonly used biological markers will be assessed against their respective role and limitations in staging hepatic fibrosis. Recent evidence highlights that both liver stiffness and some bio-chemical markers correlate with survival and major clinical end-points such as liver decompensation, development of hepatocellular carcinoma and portal hypertension. Thus the non-invasive techniques here discussed can play a major role in the management of patients with chronic HBV-related hepatitis. Given their prognostic value, transient elastography and some bio-chemical markers can be used to better categorize patients with advanced fibrosis and cirrhosis and assign them to different classes of risk for clinically relevant outcomes. Very recent data indicates that the combined measurements of liver and spleen stiffness enable the reliable prediction of portal hypertension and esophageal varices development.

Spleen stiffness measurement by transient elastography to diagnose portal hypertension in children

BACKGROUND

The development of esophageal varices is a late complication of chronic liver disease (LD) in children. The diagnosis is presently limited to invasive procedures such as endoscopy. Noninvasive tools to diagnose the presence and degree of esophageal varices would alter management decisions and support indications for invasive procedures in affected children. The aim of the study was to test the feasibility of spleen stiffness measurement (SSM) by transient elastography (TE; FibroScan) in children and compare data on its diagnostic use with established markers of liver fibrosis and parameters of portal hypertension.

METHODS

A total of 99 children (62 with chronic LD, 6 after liver transplantation, 31 controls) underwent SSM by TE. Fibrotest was determined in 37 children, 45 children had an additional liver stiffness measurement, and 19 underwent upper endoscopy.

RESULTS

SSM by FibroScan is feasible. Spleen size significantly determined success rate (90.5% in patients with splenomegaly vs 70.2% in patients without, P = 0.02). Spleen stiffness was significantly higher in patients with splenomegaly (62.96 vs 18.4 kPa, P < 0.001), in patients with varices (75 vs 24 kPa, P < 0.01), and in patients with a history of variceal hemorrhage (75 vs 50.25 kPa, P < 0.05). Variceal hemorrhage did not occur in patients with SSM results <60 kPa. Spleen stiffness decreased after liver transplantation, but remained elevated compared with controls (27.5 vs 16.3 kPa). Liver stiffness measurements and Fibrotest did not reflect the presence or degree of esophageal varices.

CONCLUSIONS

SSM by TE is feasible in children and the results reflect the degree and occurrence of complications. A prospective follow-up study with larger patient numbers and performance of screening endoscopies appears justified and desirable.

Treatment of abdominal pain in irritable bowel syndrome

Functional abdominal pain in the context of irritable bowel syndrome (IBS) is a challenging problem for primary care physicians, gastroenterologists and pain specialists. We review the evidence for the current and future non-pharmacological and pharmacological treatment options targeting the central nervous system and the gastrointestinal tract. Cognitive interventions such as cognitive behavioral therapy and hypnotherapy have demonstrated excellent results in IBS patients, but the limited availability and labor-intensive nature limit their routine use in daily practice. In patients who are refractory to first-line therapy, tricyclic antidepressants (TCA) and selective serotonin reuptake inhibitors are both effective to obtain symptomatic relief, but only TCAs have been shown to improve abdominal pain in meta-analyses. A diet low in fermentable carbohydrates and polyols (FODMAP) seems effective in subgroups of patients to reduce abdominal pain, bloating, and to improve the stool pattern. The evidence for fiber is limited and only isphagula may be somewhat beneficial. The efficacy of probiotics is difficult to interpret since several strains in different quantities have been used across studies. Antispasmodics, including peppermint oil, are still considered the first-line treatment for abdominal pain in IBS. Second-line therapies for diarrhea-predominant IBS include the non-absorbable antibiotic rifaximin and the 5HT3 antagonists alosetron and ramosetron, although the use of the former is restricted because of the rare risk of ischemic colitis. In laxative-resistant, constipation-predominant IBS, the chloride-secretion stimulating drugs lubiprostone and linaclotide, a guanylate cyclase C agonist that also has direct analgesic effects, reduce abdominal pain and improve the stool pattern.

Liver stiffness measurement by acoustic radiation force impulse is useful in predicting the presence of esophageal varices or high-risk esophageal varices among patients with HCV-related cirrhosis

BACKGROUND

Screening and periodic surveillance for esophageal varices (EVs) by esophagogastroduodenoscopy (EGD) are recommended for cirrhotic patients. We investigated non-invasive liver stiffness measurement using acoustic radiation force impulse (ARFI) for the diagnosis of EV presence and high-risk EVs among patients with HCV-related cirrhosis.

METHODS

Among 181 consecutive patients with HCV-related cirrhosis, we studied 135 patients who had received EGD and ARFI. Serum fibrosis markers [platelet count, FIB-4, and aspartate aminotransferase-to-platelet ratio index (APRI)] were measured in a training set of 92 patients and compared with ARFI in the diagnostic performance for EV presence and high-risk EVs. Furthermore, the obtained optimal cutoff values of ARFI were prospectively examined in a validation set of 43 patients.

RESULTS

In the training set, the ARFI value increased with the EV grade (p < 0.001). The ARFI value for high-risk EVs was significantly higher than that for low-risk EVs (p < 0.001). AUROC values for diagnosis of EV presence and high-risk EVs by ARFI were 0.890 and 0.868, which had the highest diagnostic performance among factors including serum fibrosis markers. The optimal cutoff value of ARFI for EV presence was 2.05 m/s with good sensitivity (83%), specificity (76%), PPV (78%), and NPV (81%), and that for high-risk EVs was 2.39 m/s with good sensitivity (81%), specificity (82%), PPV (69%), and NPV (89%). These cutoff values obtained in the training cohort also showed excellent performance in the validation set.

CONCLUSIONS

Liver stiffness measurement by ARFI is useful in predicting EV presence or high-risk EVs among patients with HCV-related cirrhosis.

Considering angle selection when using ultrasound electrode displacement elastography to evaluate radiofrequency ablation of tissues

Percutaneous radiofrequency ablation (RFA) is a minimally invasive treatment to thermally destroy tumors. Ultrasound-based electrode-displacement elastography is an emerging technique for evaluating the region of RFA-induced lesions. The angle between the imaging probe and the RFA electrode can influence electrode-displacement elastography when visualizing the ablation zone. We explored the angle effect on electrode-displacement elastography to measure the ablation zone. Phantoms embedded with meatballs were fabricated and then ablated using an RFA system to simulate RFA-induced lesions. For each phantom, a commercial ultrasound scanner with a 7.5 MHz linear probe was used to acquire raw image data at different angles, ranging from 30° to 90° at increments of 10°, to construct electrode-displacement images and facilitate comparisons with tissue section images. The results revealed that the ablation regions detected using electrode-displacement elastography were highly correlated with those from tissue section images when the angle was between 30° and 60°. However, the boundaries of lesions were difficult to distinguish, when the angle was larger than 60°. The experimental findings suggest that angle selection should be considered to achieve reliable electrode-displacement elastography to describe ablation zones.

Accuracy of spleen stiffness measurement in detection of esophageal varices in patients with chronic liver disease: systematic review and meta-analysis

BACKGROUND & AIMS

Spleen stiffness measurement (SSM) is a promising noninvasive alternative to esophagogastroduodenoscopy (EGD) that could be used in the diagnosis of esophageal varices (EV) in patients with cirrhosis. However, its overall diagnostic accuracy in various clinical settings is unknown. We conducted a systematic review and meta-analysis of studies that compared the accuracy of SSM with that of EGD in detecting EV in patients with chronic liver disease.

METHODS

Through a systematic search of bibliographic databases and conference proceedings, and contact with authors, we identified 12 studies that reported the accuracy of SSM, compared with EGD, in the diagnosis of any and/or clinically significant EV in adults with chronic liver disease. In a meta-analysis, we combined measures of test performance of individual studies.

RESULTS

Based on pooled estimates, SSM detected the presence of any EV with 78% sensitivity (95% confidence interval [CI], 75%-81%), 76% specificity (95% CI, 72%-79%), a positive likelihood ratio (LR) of 3.4 (95% CI, 2.3-4.9), a negative LR of 0.2 (95% CI, 0.1-0.4), and a diagnostic odds ratio of 19.3 (95% CI, 7.5-49.8). In a meta-analysis of 9 studies, SSM detected the presence of clinically significant EV with 81% sensitivity (95% CI, 76%-86%), 66% specificity (95% CI, 61%-69%), a positive LR of 2.5 (95% CI, 1.7-3.9), a negative LR of 0.2 (95% CI, 0.1-0.5), and a diagnostic odds ratio of 12.6 (95% CI, 5.5-28.7). There was significant heterogeneity among studies owing to differences in elastography techniques and study locations. The included studies that were at risk for spectrum bias, review bias, and disease progression bias.

CONCLUSIONS

Based on a meta-analysis, current techniques for measuring spleen stiffness are limited in their accuracy of EV diagnosis; these limitations preclude widespread use in clinical practice at this time.

Acoustic radiation force impulse elastography of the kidneys: is shear wave velocity affected by tissue fibrosis or renal blood flow?

OBJECTIVES

The aim of this study was to identify the main influencing factor of the shear wave velocity (SWV) of the kidneys measured by acoustic radiation force impulse elastography.

METHODS

The SWV was measured in the kidneys of 14 healthy volunteers and 319 patients with chronic kidney disease. The estimated glomerular filtration rate was calculated by the serum creatinine concentration and age. As an indicator of arteriosclerosis of large vessels, the brachial-ankle pulse wave velocity was measured in 183 patients.

RESULTS

Compared to the degree of interobserver and intraobserver deviation, a large variance of SWV values was observed in the kidneys of the patients with chronic kidney disease. Shear wave velocity values in the right and left kidneys of each patient correlated well, with high correlation coefficients (r = 0.580-0.732). The SWV decreased concurrently with a decline in the estimated glomerular filtration rate. A low SWV was obtained in patients with a high brachial-ankle pulse wave velocity. Despite progression of renal fibrosis in the advanced stages of chronic kidney disease, these results were in contrast to findings for chronic liver disease, in which progression of hepatic fibrosis results in an increase in the SWV. Considering that a high brachial-ankle pulse wave velocity represents the progression of arteriosclerosis in the large vessels, the reduction of elasticity succeeding diminution of blood flow was suspected to be the main influencing factor of the SWV in the kidneys.

CONCLUSIONS

This study indicates that diminution of blood flow may affect SWV values in the kidneys more than the progression of tissue fibrosis. Future studies for reducing data variance are needed for effective use of acoustic radiation force impulse elastography in patients with chronic kidney disease.

Pathophysiology of portal hypertension

Portal hypertension is a major complication of liver disease that results from a variety of pathologic conditions that increase the resistance to the portal blood flow into the liver. As portal hypertension develops, the formation of collateral vessels and arterial vasodilation progresses, which results in increased blood flow to the portal circulation. Hyperdynamic circulatory syndrome develops, leading to esophageal varices or ascites. This article summarizes the factors that increase (1) intrahepatic vascular resistance and (2) the blood flow in the splanchnic and systemic circulations in liver cirrhosis. In addition, the future directions of basic/clinical research in portal hypertension are discussed.

Invasive and noninvasive methods to diagnose portal hypertension and esophageal varices

Assessing the presence of clinically significant portal hypertension and esophageal varices is clinically important in cirrhosis. The reference standard techniques to assess the presence of portal hypertension and varices are the measurement of the hepatic vein pressure gradient and esophagogastroduodenoscopy, respectively. Some newer methods have shown a good performance, but none has been proven precise enough to replace hepatic vein pressure gradient measurement or esophagogastroduodenoscopy for the diagnosis of portal hypertension or the presence and grade of esophageal varices.