Ultrasound elastography for fibrosis surveillance is cost effective in patients with chronic hepatitis C virus in the UK

Intestinal Elastography in the Diagnostics of Ulcerative Colitis: A Narrative Review

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) that mainly affects developed countries, but the number of cases in developing countries is increasing. We conducted a narrative review on the potential application of ultrasound elastography in the diagnosis and monitoring of UC, as this newly emerging method has promising results in other gut diseases. This review fulfilled the PRISMA Statement criteria with a time cut-off of June 2022. At the end of the review, of the 1334 identified studies, only five fulfilled all the inclusion criteria. Due to the small number of studies in this field, a reliable assessment of the usefulness of ultrasound elastography is difficult. We can only conclude that the transabdominal elastography examination did not significantly differ from the standard gastrointestinal ultrasonography examination and that measurements of the frontal intestinal wall should be made in the longitudinal section. The reports suggest that it is impossible to estimate the clinical scales used in disease assessment solely on the basis of elastographic measurements. Due to the different inclusion criteria, measurement methodologies, and elastographic techniques used in the analysed studies, a reliable comparative evaluation was impossible. Further work is required to assess the validity of expanding gastrointestinal ultrasonography with elastography in the diagnosis and monitoring of UC.

Discovery, validation and sequencing of urinary peptides for diagnosis of liver fibrosis-A multicentre study

Background

Liver fibrosis is a consequence of chronic inflammation and is associated with protein changes within the hepatocytes structure. In this study, we aimed to investigate if this is reflected by the urinary proteome and can be explored to diagnose liver fibrosis in patients with chronic liver disease.

Methods

In a multicentre combined cross-sectional and prospective diagnostic test validation study, 129 patients with varying degrees of liver fibrosis and 223 controls without liver fibrosis were recruited. Additionally, 41 patients with no liver, but kidney fibrosis were included to evaluate interference with expressions of kidney fibrosis. Urinary low molecular weight proteome was analysed by capillary electrophoresis coupled to mass spectrometry (CE-MS) and a support vector machine marker model was established by integration of peptide markers for liver fibrosis.

Findings

CE-MS enabled identification of 50 urinary peptides associated with liver fibrosis. When combined into a classifier, LivFib-50, it separated patients with liver fibrosis (N = 31) from non-liver disease controls (N = 123) in cross-sectional diagnostic phase II evaluation with an area under the curve (AUC) of 0.94 (95% confidence intervals (CI): 0.89–0.97, p<0.0001). When adjusted for age, LivFib-50 demonstrated an AUC of 0.94 (95% CI: 0.89–0.97, p<0.0001) in chronic liver disease patients with (N = 19) or without (N = 17) liver fibrosis progression. In this prospective diagnostic phase III validation set, age-adjusted LivFib-50 showed 84.2% sensitivity (95% CI: 60.4–96.6) and 82.4% specificity (95% CI: 56.6–96.2) for detection of liver fibrosis. The sequence-identified peptides are mainly fragments of collagen chains, uromodulin and Na/K-transporting ATPase subunit γ. We also identified ten putative proteolytic cleavage sites, eight were specific for matrix metallopeptidases and two for cathepsins.

Interpretation

In liver fibrosis, urinary peptides profiling offers potential diagnostic markers and leads to discovery of proteolytic sites that could be targets for developing anti-fibrotic therapy.

Correlation between Serum Ferritin Levels and Liver Stiffness measured by Fibroscan in patients with Chronic Hepatitis C

Objective

To determine correlation between transient elastography values with serum ferritin and duration of infection in patients of hepatitis C.

Methods

A cross-sectional study was conducted at medical units of Civil Hospital, Karachi. The study protocol was approved by the Research Evaluation Unit of College of Physician and Surgeon Pakistan (CPSP). Patients fulfilling inclusion criteria were included after taking informed consent. Serum ferritin levels were tested by standard laboratory procedures and transient elastography by fibroscan. Regression analysis was done to see correlation of ferritin with transient elastography and duration of HCV.

Results

Over all 120 patients fulfilling the selection criteria were selected after informed consent. These included 68 (56.7%) male & 52 (43.3%) female. Significant differences in ferritin levels by Fibrosis stages were observed by ANOVA (df = 3; F =12.768; p = <0.001). Serum ferritin showed linear pattern across Fibrosis stages (F = 33.948; p = <0.001). Regression analysis of ferritin and duration of HCV showed significant impact on TE scores (r² = 0.317).

Conclusions

There is significant correlation between serum ferritin and duration of HCV with TE scores.

Cost-effectiveness of diagnostic and therapeutic interventions for chronic hepatitis C: a systematic review of model-based analyses

BACKGROUND

Decisions about which subgroup of chronic hepatitis C (CHC) patients should be treated with direct acting anti-viral agents (DAAs) have economic importance due to high drug prices. Treat-all DAA strategies for CHC have gained acceptance despite high drug acquisition costs. However, there are also costs associated with the surveillance of CHC to determine a subgroup of patients with significant impairment. The aim of this systematic review was to describe the modelling methods used and summarise results in cost-effectiveness analyses (CEAs) of both CHC treatment with DAAs and surveillance of liver disease.

METHODS

Electronic databases including Embase and Medline were searched from inception to May 2015. Eligible studies included models predicting costs and/or outcomes for interventions, surveillance, or management of people with CHC. Narrative and quantitative synthesis were conducted. Quality appraisal was conducted using validated checklists. The review was conducted following principles published by NHS Centre for Research and Dissemination.

RESULTS

Forty-one CEAs met the eligibility criteria for the review; 37 evaluated an intervention and four evaluated surveillance strategies for targeting DAA treatment to those likely to gain most benefit. Included studies were of variable quality mostly due to reporting omissions. Of the 37 CEAs, eight models that enabled comparative analysis were fully appraised and synthesized. These models provided non-unique cost-effectiveness estimates in a specific DAA comparison in a specific population defined in terms of genotype, prior treatment status, and presence or absence of cirrhosis. Marked heterogeneity in cost-effectiveness estimates was observed despite this stratification. Approximately half of the estimates suggested that DAAs were cost-effective considering a threshold of US$30,000 and 73% with threshold of US$50,000. Two models evaluating surveillance strategies suggested that treating all CHC patients regardless of the staging of liver disease could be cost-effective.

CONCLUSIONS

CEAs of CHC treatments need to better account for variability in their estimates. This analysis suggested that there are still circumstances where DAAs are not cost-effective. Surveillance in place of a treat-all strategy may still need to be considered as an option for deploying DAAs, particularly where acquisition cost is at the limit of affordability for a given health system.

Individualized risk estimation for postoperative morbidity after hepatectomy: the Humanitas score

BACKGROUND

Estimation of postoperative morbidity after hepatectomy remains challenging. The aim of this prospective study was to develop a surgical score to predict an individual risk of post-hepatectomy complications.

METHODS

All consecutive patients scheduled for hepatectomy from February 2012 to September 2015 were included and randomly assigned into a derivation or validation cohort. We developed a score based on preoperative variables, and we tested them using multivariate analyses. Odds-ratio (OR) values were used to build the score.

RESULTS

340 patients were included, 240 in the derivation and 100 in the validation cohort. Multivariate analysis showed that major hepatectomy (OR = 1.62; 95% CI 1.39-3.51), liver stiffness ≥9.7 kPa (OR = 2.46; 95% CI 1.16-5.28), BILCHE score (combination of serum bilirubin and cholinesterase) ≥2 (OR = 2.76; 95% CI 0.82-4.28) and esophageal varices (OR = 1.59; 95% CI 1.51-3.61) were independent complications predictors. A 10-point scoring system was introduced. Patients with a score ≤4 did not experience complications, whereas patients with ≥7 points experienced up to 54% of complications (P < 0.001).

CONCLUSIONS

A new, easy and clinically reliable surgical score based on the liver stiffness, BILCHE score, type of hepatectomy, and presence of varices may be used to predict post-hepatectomy morbidity.

CLINICAL TRIAL NUMBER

NCT02454686 (https://www.clinicaltrials.gov/).

Transient elastography for the diagnosis of liver fibrosis: a systematic review of economic evaluations

BACKGROUND

Liver biopsy remains the gold standard for the diagnosis of liver fibrosis, but its use as a diagnostic tool is limited by its invasive nature and high cost.

OBJECTIVE

The aim of this study was to systematically review the cost-effectiveness of transient elastography (TE) with and without controlled attenuation parameter (CAP) for the diagnosis of liver fibrosis or steatosis in patients with hepatitis B, hepatitis C, alcoholic liver disease and non-alcoholic fatty liver disease.

METHODS

An economic literature search was performed. Eligibility criteria included systematic reviews, health technology assessments or economic evaluations of TE compared to liver biopsy and other non-invasive tests. After abstract screening, full-text reports of potentially relevant articles were assessed in duplicate. The methodological quality of the included studies was also appraised.

RESULTS

The database search yielded 253 records; four cost-effectiveness and four cost-utility studies were included. The methodological quality of the included studies varies. High-quality cost-effectiveness studies not only suggested that TE is less costly but also less accurate than liver biopsy. The incremental cost-effectiveness ratio (ICER) of TE improves with a greater level of diagnostic accuracy and a higher degree of liver fibrosis. High-quality cost-utility studies indicated that TE is a cost-effective alternative to biopsy with ICER between $9000 and $14 000 per QALY for patients with hepatitis C. We did not find studies that assessed the cost-effectiveness of TE with CAP for the diagnosis of liver steatosis.

CONCLUSIONS

Transient elastography is an economically attractive alternative to liver biopsy and other non-invasive diagnostic tests especially for patients with a higher degree of liver fibrosis.

Enhanced liver fibrosis test using ELISA assay accurately discriminates advanced stage of liver fibrosis as determined by transient elastography fibroscan in treatment naïve chronic HCV patients

Evaluation of liver fibrosis stage is crucial in the assessment of chronic HCV patients, regarding decision to start treatment and during follow-up. Our aim was to assess the validity of the enhanced liver fibrosis (ELF) score in discrimination of advanced stage of liver fibrosis in naïve chronic HCV patients. We prospectively evaluated liver fibrosis stage in one hundred eighty-one naïve chronic HCV Egyptian patients by transient elastography (TE)-FibroScan. Patients were categorized into mild to moderate fibrosis (≤F2) group and advanced fibrosis (≥F3) group. The ELF score components, hyaluronic acid (HA), amino-terminal propeptide of type-III-procollagen (PIIINP) and tissue inhibitor of metalloproteinase type-1 (TIMP-1), were done using ELISA test. The mean values of ELF and its individual components significantly correlated with the hepatic fibrosis stage as measured by TE-FibroScan (P value 0.001). ELF cutoff value of 9.8 generated a sensitivity of 77.8%, specificity of 67.1%, area under the receiver operator characteristic curve (AUROC) of 0.76 with 95% confidence interval [CI] (0.68-0.83) for detecting advanced fibrosis (F ≥ 3). ELF panel is a good, reliable noninvasive test and showed comparable results to TE-FibroScan in detecting liver fibrosis stage in treatment naïve chronic HCV patients.

Cost-effectiveness of enhanced liver fibrosis test to assess liver fibrosis in chronic hepatitis C virus and alcoholic liver disease patients

AIM

To assess liver fibrosis (LF) in hepatitis C virus (HCV) and alcoholic liver disease (ALD), estimate health outcomes and costs of new noninvasive testing strategies

METHODS

A Markov model was developed to simulate LF progression in HCV and ALD for a cohort of 40-year-old men with abnormal levels of transaminases. Three different testing alternatives were studied: a single liver biopsy; annual Enhanced liver fibrosis (ELF™) followed by liver stiffness measurement (LSM) imaging as a confirmation test if the ELF test is positive; and annual ELF test without LSM. The analysis was performed from the perspective of a university hospital in Spain. Clinical data were obtained from published literature. Costs were sourced from administrative databases of the hospital. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

In HCV patients, annual sequential ELF test/LSM and annual ELF test alone prevented respectively 12.9 and 13.3 liver fibrosis-related deaths per 100 persons tested, compared to biopsy. The incremental cost-effectiveness ratios (ICERs) were respectively €13400 and €11500 per quality-adjusted life year (QALY). In ALD, fibrosis-related deaths decreased by 11.7 and 22.1 per 100 persons tested respectively with sequential ELF test/LSM and annual ELF test alone. ICERs were €280 and €190 per QALY, respectively.

CONCLUSION

The use of the ELF test with or without a confirmation LSM are cost-effective options compared to a single liver biopsy for testing liver fibrosis in HCV and ALD patients in Spain.

Real-World Data for the Evaluation of Transarterial Radioembolization versus Sorafenib in Hepatocellular Carcinoma: A Cost-Effectiveness Analysis

OBJECTIVES

To perform a cost-effectiveness analysis comparing the use of transarterial radioembolization (TARE) with that of sorafenib in the treatment of patients with intermediate or advanced hepatocellular carcinoma (HCC) according to the Barcelona Clinic Liver Cancer staging system.

METHODS

Patient-level data were consecutively recorded and collected at three oncology centers in Italy. A propensity score matching was performed to compare patients with similar clinical characteristics who underwent TARE or sorafenib treatment. Clinical data from the matched cohorts were used to populate a Markov model to project, on a lifetime horizon, life years, quality-adjusted life years, and economic outcomes associated with TARE and sorafenib for both intermediate and advanced HCC stages.

RESULTS

Starting from data covering 389 and 241 patients who underwent TARE and sorafenib treatment, respectively, the propensity score matching yielded a total of 308 matched patients. For intermediate-stage patients, the model estimated for TARE versus sorafenib an incremental cost-utility ratio of €3,302/QALY (incremental cost-effectiveness ratio of €1,865 per life year gained), whereas for patients in advanced stage TARE dominated (lower costs and greater health improvements) compared with sorafenib.

CONCLUSIONS

From an Italian health care service perspective, TARE could be a cost-effective strategy in comparison with sorafenib for patients with intermediate or advanced HCC. The results from forthcoming randomized controlled trials comparing TARE with sorafenib will be able to confirm or reject the validity of this preliminary evaluation. In the meantime, decision makers can use these results to control and coordinate the diffusion of the technology.

Asian-Pacific Association for the Study of the Liver (APASL) consensus guidelines on invasive and non-invasive assessment of hepatic fibrosis: a 2016 update

Hepatic fibrosis is a common pathway leading to liver cirrhosis, which is the end result of any injury to the liver. Accurate assessment of the degree of fibrosis is important clinically, especially when treatments aimed at reversing fibrosis are being evolved. Despite the fact that liver biopsy (LB) has been considered the "gold standard" of assessment of hepatic fibrosis, LB is not favored by patients or physicians owing to its invasiveness, limitations, sampling errors, etc. Therefore, many alternative approaches to assess liver fibrosis are gaining more popularity and have assumed great importance, and many data on such approaches are being generated. The Asian Pacific Association for the Study of the Liver (APASL) set up a working party on liver fibrosis in 2007, with a mandate to develop consensus guidelines on various aspects of liver fibrosis relevant to disease patterns and clinical practice in the Asia-Pacific region. The first consensus guidelines of the APASL recommendations on hepatic fibrosis were published in 2009. Due to advances in the field, we present herein the APASL 2016 updated version on invasive and non-invasive assessment of hepatic fibrosis. The process for the development of these consensus guidelines involved review of all available published literature by a core group of experts who subsequently proposed consensus statements followed by discussion of the contentious issues and unanimous approval of the consensus statements. The Oxford System of the evidence-based approach was adopted for developing the consensus statements using the level of evidence from one (highest) to five (lowest) and grade of recommendation from A (strongest) to D (weakest). The topics covered in the guidelines include invasive methods (LB and hepatic venous pressure gradient measurements), blood tests, conventional radiological methods, elastography techniques and cost-effectiveness of hepatic fibrosis assessment methods, in addition to fibrosis assessment in special and rare situations.

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.

Ultrasound elastography: liver

Ultrasound elastography, also termed sonoelastography, is being used increasingly in clinical practice to aid the diagnosis and management of diffuse liver disease. Elastography has been shown to be capable of differentiating advanced and early-stage liver fibrosis, and consequently a major application in clinical liver care includes progression to cirrhosis risk stratification through (1) assessment of liver fibrosis stage in HCV and HBV patients, (2) distinguishing non-alcoholic steatohepatitis from simple steatosis in non-alcoholic fatty liver disease patients, and (3) prognostic evaluation of liver disease is autoimmune liver disease. In addition, elastographic characterization of focal liver lesions and evaluation of clinically significant portal hypertension have the potential to be clinically useful and are areas of active clinical research.

Impact of Hepatitis C Virus Infection on Hepatocellular Carcinoma

Hepatitis C virus (HCV)-associated hepatocellular carcinoma (HCC) incidence in the United States is increasing, partly because of risk factors such as diabetes, fatty liver, hepatitis B virus, and human immunodeficiency virus coinfection. Achieving sustained virologic response (SVR) is the most significant factor in reducing HCV-associated HCC incidence. Improved SVR with the next generation of direct-acting antivirals brings hope for decreased HCC mortality. Nevertheless, surveillance for HCC remains important because HCC can still occur despite SVR, especially in cirrhotics. Individualized risk stratification through increased understanding of HCC pathogenesis and improved surveillance holds the promise for future reduction of HCC incidence.

Transient Elastography and Controlled Attenuation Parameter for Diagnosing Liver Fibrosis and Steatosis in Ontario: An Economic Analysis

BACKGROUND

Liver fibrosis is characterized by a buildup of connective tissue due to chronic liver damage. Steatosis is the collection of excessive amounts of fat inside liver cells. Liver biopsy remains the gold standard for the diagnosis of liver fibrosis and steatosis, but its use as a diagnostic tool is limited by its invasive nature and high cost.

OBJECTIVES

To evaluate the cost-effectiveness and budget impact of transient elastography (TE) with and without controlled attenuation parameter (CAP) for the diagnosis of liver fibrosis or steatosis in patients with hepatitis B, hepatitis C, alcoholic liver disease, and nonalcoholic fatty liver disease.

DATA SOURCES

An economic literature search was performed using computerized databases. For primary economic and budget impact analyses, we obtained data from various sources, such as the Health Quality Ontario evidence-based analysis, published literature, and the Institute for Clinical Evaluative Sciences.

REVIEW METHODS

A systematic review of existing TE cost-effectiveness studies was conducted, and a primary economic evaluation was undertaken from the perspective of the Ontario Ministry of Health and Long-Term Care. Decision analytic models were used to compare short-term costs and outcomes of TE compared to liver biopsy. Outcomes were expressed as incremental cost per correctly diagnosed cases gained. A budget impact analysis was also conducted.

RESULTS

We included 10 relevant studies that evaluated the cost-effectiveness of TE compared to other noninvasive tests and to liver biopsy; no cost-effectiveness studies of TE with CAP were identified. All studies showed that TE was less expensive but associated with a decrease in the number of correctly diagnosed cases. TE also improved quality-adjusted life-years in patients with hepatitis B and hepatitis C. Our primary economic analysis suggested that TE led to cost savings but was less effective than liver biopsy in the diagnosis of liver fibrosis. TE became more economically attractive with a higher degree of liver fibrosis. TE with CAP was also less expensive and less accurate than liver biopsy.

LIMITATIONS

The model did not take into account long-term costs and consequences associated with TE and liver biopsy and did not include costs to patients and their families, or patient preferences related to diagnostic information.

CONCLUSIONS

TE showed potential cost savings compared to liver biopsy. Further investigation is needed to determine the long-term impacts of TE on morbidity and mortality in Canada and the optimal diagnostic modality for liver fibrosis and steatosis.

Cost-Effective Evaluation of Nonalcoholic Fatty Liver Disease With NAFLD Fibrosis Score and Vibration Controlled Transient Elastography

OBJECTIVES

The risk of advanced fibrosis in nonalcoholic fatty liver disease (NAFLD) is traditionally assessed with a liver biopsy, which is both costly and associated with adverse events.

METHODS

We sought to compare the cost-effectiveness of four different strategies to assess fibrosis risk in patients with NAFLD: vibration controlled transient elastography (VCTE), the NAFLD fibrosis score (NFS), combination testing with NFS and VCTE, and liver biopsy (usual care). We developed a probabilistic decision analytical microsimulation state-transition model wherein we simulated a cohort of 10,000 50-year-old Americans with NAFLD undergoing evaluation by a gastroenterologist. VCTE performance was obtained from a prospective cohort of 144 patients with NAFLD.

RESULTS

Both the NFS alone and the NFS/VCTE strategies were cost effective at $5,795 and $5,768 per quality-adjusted life years (QALY), respectively. In the microsimulation, the NFS alone and NFS/VCTE strategies were the most cost-effective (dominant) in 66.8 and 33.2% of samples given a willingness-to-pay threshold of $100,000 per QALY. In a sensitivity analysis, the minimum cost per liver biopsy at which the NFS is cost saving is $339 and the maximum cost per VCTE exam at which the NFS/VCTE strategy remains cost saving is $1,593. The expected value of further research on this topic is $526 million.

CONCLUSIONS

Non-invasive risk stratification with both the NFS alone and the NFS/VCTE are cost-effective strategies for the evaluation and management of patients with NAFLD presenting to a gastroenterologist. Further research is needed to better define the natural history of NAFLD and the effect of novel treatments on decision making.

Economic evaluation of screening programs for hepatitis C virus infection: evidence from literature

BACKGROUND

Hepatitis C is a liver infection caused by hepatitis C virus. Its main complications are cirrhosis and liver cancer. According to the World Health Organization (WHO), more than 185 million people worldwide are infected with hepatitis C virus and, of these, 350,000 die every year. Due to the high disease prevalence and the existence of effective (and expensive) medical treatments able to dramatically change the prognosis, early detection programs can potentially prevent the development of serious chronic conditions, improve health, and save resources.

OBJECTIVE

To summarize the available evidence on the cost-effectiveness of screening programs for hepatitis C.

METHODS

A literature search was performed on PubMed and Scopus search engines. Trip database was queried to identify reports produced by the major Health Technology Assessment (HTA) agencies. Three reviewers dealt with study selection and data extraction blindly.

RESULTS

Ten papers eventually met the inclusion criteria. In studies focusing on asymptomatic cohorts of individuals at general risk the cost/quality adjusted life year of screening programs ranged between US $4,200 and $50,000/quality adjusted life year gained, while in those focusing on specific risk factors the incremental cost-effectiveness ratio ranged between $848 and $128,424/quality adjusted life year gained. Age of the target population and disease prevalence were the main cost-effectiveness drivers.

CONCLUSION

Our results suggest that, especially in the long run, screening programs represent a cost-effective strategy for the management of hepatitis C.

Combination of blood tests for significant fibrosis and cirrhosis improves the assessment of liver-prognosis in chronic hepatitis C

BACKGROUND

Recent longitudinal studies have emphasised the prognostic value of noninvasive tests of liver fibrosis and cross-sectional studies have shown their combination significantly improves diagnostic accuracy.

AIM

To compare the prognostic accuracy of six blood fibrosis tests and liver biopsy, and evaluate if test combination improves the liver-prognosis assessment in chronic hepatitis C (CHC).

METHODS

A total of 373 patients with compensated CHC, liver biopsy (Metavir F) and blood tests targeting fibrosis (APRI, FIB4, Fibrotest, Hepascore, FibroMeter) or cirrhosis (CirrhoMeter) were included. Significant liver-related events (SLRE) and liver-related deaths were recorded during follow-up (started the day of biopsy).

RESULTS

During the median follow-up of 9.5 years (3508 person-years), 47 patients had a SLRE and 23 patients died from liver-related causes. For the prediction of first SLRE, most blood tests allowed higher prognostication than Metavir F [Harrell C-index: 0.811 (95% CI: 0.751-0.868)] with a significant increase for FIB4: 0.879 [0.832-0.919] (P = 0.002), FibroMeter: 0.870 [0.812-0.922] (P = 0.005) and APRI: 0.861 [0.813-0.902] (P = 0.039). Multivariate analysis identified FibroMeter, CirrhoMeter and sustained viral response as independent predictors of first SLRE. CirrhoMeter was the only independent predictor of liver-related death. The combination of FibroMeter and CirrhoMeter classifications into a new FM/CM classification improved the liver-prognosis assessment compared to Metavir F staging or single tests by identifying five subgroups of patients with significantly different prognoses.

CONCLUSIONS

Some blood fibrosis tests are more accurate than liver biopsy for determining liver prognosis in CHC. A new combination of two complementary blood tests, one targeted for fibrosis and the other for cirrhosis, optimises assessment of liver-prognosis.

The clinical utility of FibroScan(®) as a noninvasive diagnostic test for liver disease

An important aspect of managing chronic liver disease is assessing for evidence of fibrosis. Historically, this has been accomplished using liver biopsy, which is an invasive procedure associated with risk for complications and significant sampling and observer error, limiting the accuracy for determination of fibrosis stage. Hence, several serum biomarkers and imaging methods for noninvasive assessment of liver fibrosis have been developed. In this article, we review the current literature on an important noninvasive imaging modality to measure tissue elastography (FibroScan^®). This ultrasound-based technique is now increasingly available in many countries and has been shown to be a reliable and safe noninvasive means of assessing disease severity in chronic liver disease of varying etiology.

Health services and policy research in hepatology

PURPOSE OF REVIEW

This article examines recent health services and policy research studies in hepatology and liver transplantation.

RECENT FINDINGS

Critical issues include access to medical care, timeliness of referral and consultation, resource utilization in clinical practice, comparative effectiveness research, and the evaluation of care delivery models. Despite policymaking efforts, there continues to be unwarranted variation in access to subspecialty care and liver transplantation services based on race and geographic location. Variations in primary care and specialist awareness of practice guidelines for liver disease contribute to disparities in appropriateness and timeliness of treatments. Defining the cost-effectiveness of increased resource utilization for novel antiviral therapies and liver transplantation continues to stimulate controversy. Few comparative effectiveness studies in hepatology exist to date, yet a growing number of analyses using national datasets will help inform policy in this arena. Identifying care delivery models that demonstrate high value for populations with chronic liver disease is critical in the context of recent healthcare reform efforts.

SUMMARY

Health services and policy research is a growing field of investigation in hepatology and liver transplantation. Further emphasis on research training and workforce development in this area will be critical for understanding and improving patient-centered outcomes for this population.

Spatially heterogeneous corneal mechanical responses before and after riboflavin-ultraviolet-A crosslinking

PURPOSE

To determine the heterogeneous through-thickness strains in the cornea at physiologic intraocular pressures before and after corneal collagen crosslinking (CXL) using noninvasive ultrasound.

SETTING

Department of Biomedical Engineering, Ohio State University, Columbus, Ohio, USA.

DESIGN

Experimental study.

METHODS

Sixteen paired canine corneoscleral shells were divided into 2 groups. The CXL group completed a standard CXL protocol using riboflavin-ultraviolet-A (UVA) irradiation. The control group was given an identical treatment except UVA irradiation. Ultrasound scans (at 55 MHz) of the cornea were obtained before and after treatment as the corneoscleral shell was inflated from 5 mm Hg to 45 mm Hg to calculate the distributive through-thickness strains in the cornea. The mean radial and tangential strains of the whole cornea layer, as well as those of the anterior, middle, and posterior thirds of the cornea, were compared before and after treatment in the control group and CXL group using linear mixed models with repeated measures.

RESULTS

Significant reductions in tangential and radial strains occurred in the CXL group (P=.003 and P=.0025, respectively) but not the control group (P=.08 and P=.63, respectively). The anterior third had the smallest strains in all pretreated corneas (P<.001) and posttreated corneas (CXL group, P=.023; control group, P=.01).

CONCLUSIONS

Ultrasound speckle tracking showed heterogeneous strain distributions through the cornea and confirmed that CXL results in a stiffer corneal response (ie, smaller strains during physiologic loadings). This technique may provide a clinical tool to quantify the biomechanical effects of CXL.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Non-invasive diagnosis of liver fibrosis in chronic hepatitis C

Assessment of liver fibrosis in chronic hepatitis C virus (HCV) infection is considered a relevant part of patient care and key for decision making. Although liver biopsy has been considered the gold standard for staging liver fibrosis, it is an invasive technique and subject to sampling errors and significant intra- and inter-observer variability. Over the last decade, several noninvasive markers were proposed for liver fibrosis diagnosis in chronic HCV infection, with variable performance. Besides the clear advantage of being noninvasive, a more objective interpretation of test results may overcome the mentioned intra- and inter-observer variability of liver biopsy. In addition, these tests can theoretically offer a more accurate view of fibrogenic events occurring in the entire liver with the advantage of providing frequent fibrosis evaluation without additional risk. However, in general, these tests show low accuracy in discriminating between intermediate stages of fibrosis and may be influenced by several hepatic and extra-hepatic conditions. These methods are either serum markers (usually combined in a mathematical model) or imaging modalities that can be used separately or combined in algorithms to improve accuracy. In this review we will discuss the different noninvasive methods that are currently available for the evaluation of liver fibrosis in chronic hepatitis C, their advantages, limitations and application in clinical practice.