ObjectiveTo meta-analyse the diagnostic accuracy of US, CT, MRI and 1H-MRS for the evaluation of hepatic steatosis.MethodsFrom a comprehensive literature search in MEDLINE, EMBASE, CINAHL and Cochrane (up to November 2009), articles were selected that investigated the diagnostic performance imaging techniques for evaluating hepatic steatosis with histopathology as the reference standard. Cut-off values for the presence of steatosis on liver biopsy were subdivided into four groups: (1) >0, >2 and >5% steatosis; (2) >10, >15 and >20%; (3) >25, >30 and >33%; (4) >50, >60 and >66%. Per group, summary estimates for sensitivity and specificity were calculated. The natural-logarithm of the diagnostic odds ratio (lnDOR) was used as a single indicator of test performance.Results46 articles were included. Mean sensitivity estimates for subgroups were 73.3–90.5% (US), 46.1–72.0% (CT), 82.0–97.4% (MRI) and 72.7–88.5% (1H-MRS). Mean specificity ranges were 69.6–85.2% (US), 88.1–94.6% (CT), 76.1–95.3% (MRI) and 92.0–95.7% (1H-MRS). Overall performance (lnDOR) of MRI and 1H-MRS was better than that for US and CT for all subgroups, with significant differences in groups 1 and 2.ConclusionMRI and 1H-MRS can be considered techniques of choice for accurate evaluation of hepatic steatosis.Electronic supplementary materialThe online version of this article (doi:10.1007/s00330-010-1905-5) contains supplementary material, which is available to authorized users.

Background & Aims Magnetic resonance elastography (MRE) is a non-invasive tool for staging liver fibrosis. We conducted a meta-analysis of individual participant data collected from published studies to assess the diagnostic accuracy of MRE and for staging liver fibrosis in patients with chronic liver diseases (CLD). Methods Through a systematic literature search of multiple databases (2003–2013), we identified studies on diagnostic performance of MRE for staging liver fibrosis in patients with CLD with native anatomy, using liver biopsy as the standard. We contacted study authors to collect data on each participant’s age, sex, body mass index (BMI), liver stiffness (measured by MRE), fibrosis stage, staging system used, degree of inflammation, etiology of CLD, and interval between MRE and biopsy. Through pooled analysis, we calculated the cluster-adjusted area under receiver-operating curve (AUROC), sensitivity, and specificity of MRE for any fibrosis (≥stage 1), significant fibrosis (≥stage 2), advanced fibrosis (≥stage 3), and cirrhosis (stage 4) Results We analyzed data from 12 retrospective studies, comprising 697 patients (mean age, 55±13 years; 59.4% male; mean BMI, 26.9±6.7 kg/m2; 92.1% with <1 year interval between MRE and biopsy; hepatitis C in 47.1%). Participants had fibrosis stages 0, 1, 2, 3, or 4 (19.5%, 19.4%, 15.5%, 15.9% and 29.7%, respectively). Mean AUROC values (and 95% confidence intervals) for diagnosis of any (≥stage 1), significant (≥stage 2), or advanced fibrosis (≥stage 3), and cirrhosis, were 0.84 (0.76–0.92), 0.88 (0.84–0.91), 0.93 (0.90–0.95), and 0.92 (0.90–0.94), respectively. Similar diagnostic performance was observed in stratified analysis based on sex, obesity, and etiology of CLD. The overall rate of failure of MRE was 4.3%. Conclusion Based on pooled analysis of data from individual participants, MRE has high accuracy for diagnosis of significant or advanced fibrosis and cirrhosis, independent of BMI and etiology of CLD. Prospective studies are warranted to better understand the diagnostic performance of MRE.

• Both ultrasound-based transient elastography and magnetic resonance elastography can assess hepatic fibrosis. • Both have comparable accuracy for detecting liver fibrosis in viral hepatitis. • The individual techniques reliably detect or exclude significant liver fibrosis in 66 %. • A conditional strategy for inconclusive findings increases the number of correct diagnoses.

Background:Accurate prediction scores for liver steatosis are demanded to enable clinicians to noninvasively screen for nonalcoholic fatty liver disease (NAFLD). Several prediction scores have been developed, however external validation is lacking.Objective:The aim was to determine the diagnostic accuracy of four existing prediction scores in severely obese children, to develop a new prediction score using novel biomarkers and to compare these results to the performance of ultrasonography.Design and Results:Liver steatosis was measured using proton magnetic resonance spectroscopy in 119 severely obese children (mean age 14.3 ± 2.1 years, BMI z‐score 3.35 ± 0.35). Prevalence of steatosis was 47%. The four existing predictions scores (“NAFLD liver fat score,” “fatty liver index,” “hepatic steatosis index,” and the pediatric prediction score) had only moderate diagnostic accuracy in this cohort (positive predictive value (PPV): 70, 61, 61, 69% and negative predictive value (NPV) 77, 69, 68, 75%, respectively). A new prediction score was built using anthropometry, routine biochemistry and novel biomarkers (leptin, adiponectin, TNF‐alpha, IL‐6, CK‐18, FGF‐21, and adiponutrin polymorphisms). The final model included ALT, HOMA, sex, and leptin. This equation (PPV 79% and NPV 80%) did not perform substantially better than the four other equations and did not outperform ultrasonography for excluding NAFLD (NPV 82%).Conclusion:The conclusion is in severely obese children and adolescents existing prediction scores and the tested novel biomarkers have insufficient diagnostic accuracy for diagnosing or excluding NAFLD.