Criteria to Determine Reliability of Noninvasive Assessment of Liver Fibrosis With Virtual Touch Quantification.

BACKGROUND & AIMS: Virtual Touch Quantification (VTQ) evaluates liver fibrosis in patients with chronic liver diseases by measuring shear wave speed in the liver. We aimed to determine the reliability criteria of VTQ examination. METHODS: We performed a prospective study of 1094 patients with chronic liver disease from November 2009 through October 2016 at Angers University Hospital, and between April 2010 and May 2015 at Bordeaux University Hospital, in France. All patients underwent liver biopsy analysis (reference standard), and VTQ examination was made by experienced operators on the same day, or no more than 3 months before or afterward. Advanced liver fibrosis was defined as fibrosis stage F ≥ 3 according to the scoring system of the Nonalcoholic Steatohepatitis Clinical Research Network, or fibrosis stage F ≥ 2 according to the Metavir scoring system. The diagnostic accuracy of VTQ in detection of advanced fibrosis or cirrhosis was assessed using the area under the receiver operating characteristic (AUROC) and the rate of correctly classified patients. Reliability criteria were defined from the intrinsic characteristics of VTQ examination, which were shown to influence the diagnostic accuracy. RESULTS: VTQ identified patients with advanced fibrosis with an AUROC of 0.773 ± 0.014 and correctly classified 72.0% of patients using a diagnostic cut-off value of 1.37 m/s. VTQ identified patients with cirrhosis with an AUROC value of 0.839 ± 0.014 and correctly classified 78.4% of patients using a cut-off value of 1.87 m/s. The reliability of VTQ decreased with an increasing ratio of interquartile range/median (IQR/M) in patients with intermediate-high VTQ results. We defined 3 reliability categories for VTQ: unreliable (IQR/M ≥0.35 with VTQ result ≥1.37 m/s), reliable (IQR/M ≥0.35 with VTQ result <1.37 m/s or IQR/M 0.15-0.34), and very reliable (IQR/M <0.15). For advanced fibrosis, VTQ correctly classified 57.8% of patients in the unreliable group, 73.7% of patients in the reliable group, and 80.9% of patients in the very reliable group (P < .001); for cirrhosis, these values were 50.0%, 83.4%, and 92.6%, respectively (P < .001). Of the VTQ examinations made, 21.4% were unreliable, 55.0% were reliable, and 23.6% were very reliable. The skin-liver capsule distance was independently associated with an unreliable VTQ examination, which occurred in 52.7% of patients with a distance of 30 mm or more. CONCLUSIONS: In a study to determine the reliability of VTQ findings, compared with results from biopsy analysis, we assigned VTQ examinations to 3 categories (unreliable, reliable, and very reliable). VTQ examinations with IQR/M ≥0.35 and ≥1.37 m/s had very low diagnostic accuracy. Our reliability criteria for liver fibrosis assessment with VTQ will help physicians to accurately evaluate the severity of chronic liver diseases and monitor their progression.

Liver stiffness in nonalcoholic fatty liver disease: A comparison of supersonic shear imaging, FibroScan, and ARFI with liver biopsy.

UNLABELLED: Nonalcoholic fatty liver disease (NAFLD) has become a major public health issue. The goal of this study was to assess the clinical use of liver stiffness measurement (LSM) evaluated by supersonic shear imaging (SSI), FibroScan, and acoustic radiation force impulse (ARFI) in a cohort of NAFLD patients who underwent liver biopsy. A total of 291 NAFLD patients were prospectively enrolled from November 2011 to February 2015 at 2 French university hospitals. LSM was assessed by SSI, FibroScan (M probe), and ARFI within two weeks prior to liver biopsy. Calculations of the area under the receiver operating curve (AUROC) were performed and compared for the staging of liver fibrosis. AUROC for SSI, FibroScan, and ARFI were 0.86, 0.82, and 0.77 for diagnoses of ≥F2; 0.89, 0.86, and 0.84 for ≥F3; and 0.88, 0.87, and 0.84 for F4, respectively. SSI had a higher accuracy than ARFI for diagnoses of significant fibrosis (≥F2) (P = 0.004). Clinical factors related to obesity such as body mass index ≥ 30 kg/m(2) , waist circumference ≥102 cm or increased parietal wall thickness were associated with LSM failures when using SSI or FibroScan and with unreliable results when using ARFI. In univariate analysis, FibroScan values were slightly correlated with NAFLD activity score and steatosis (R = 0.28 and 0.22, respectively), whereas SSI and ARFI were not; however, these components of NAFLD did not affect LSM results in multivariate analysis. The cutoff values for SSI and FibroScan for staging fibrosis with a sensitivity ≥90% were very close: 6.3/6.2 kPa for ≥F2, 8.3/8.2 kPa for ≥F3, and 10.5/9.5 kPa for F4. CONCLUSION: Although obesity is associated with an increase in LSM failure, the studied techniques and especially SSI provide high value for the diagnosis of liver fibrosis in NAFLD patients. (Hepatology 2016;63:1817-1827).

Age, atrial fibrillation, and structural heart disease are the main determinants of left atrial fibrosis detected by delayed-enhanced magnetic resonance imaging in a general cardiology population.

INTRODUCTION: We studied the extent and distribution of left atrial (LA) fibrosis on delayed-enhanced (DE) MRI in a general cardiology population. METHODS AND RESULTS: One hundred ninety consecutive patients referred for cardiac MRI underwent DE imaging using a free breathing method. The population comprised 60 AF patients and 130 patients without AF, including 75 with structural heart disease (SHD). DE was quantified using histogram thresholding, expressed in % of the wall. Regression analysis was performed to identify predictors of DE. Additionally, DE was registered on a template to study its distribution in subpopulations. In the total population, age, AF, and SHD were independently associated with DE. DE was increasingly observed from 11.1 ± 4.7% in patients with no SHD nor AF, 18.8 ± 7.8% in SHD and no AF history, 22.9 ± 7.8% in paroxysmal AF, to 27.8 ± 7.7% in persistent AF. Among non-AF patients, age and SHD were independently associated with DE. Among AF patients, female gender and AF persistence were independently associated with DE. DE was variably distributed but more frequently detected in the posterior wall. CONCLUSION: Age, history of AF, and SHD are the most powerful predictors of atrial fibrosis, as detected by MRI, in a general cardiology population. Atrial fibrosis predominates in the posterior LA wall.

Non-invasive assessment of liver fibrosis with impulse elastography: comparison of Supersonic Shear Imaging with ARFI and FibroScan®.

BACKGROUND & AIMS: Non-invasive assessment of liver fibrosis by elastography is a rapidly developing field with frequent technological innovations. The aim of this study was to assess the diagnostic performances of Supersonic Shear Imaging (SSI) for the diagnosis of liver fibrosis in chronic liver disease. METHODS: A total of 349 consecutive patients with chronic liver diseases who underwent liver biopsy from November 2011 to October 2013 were prospectively enrolled. For each patient, liver stiffness was assessed by SSI, ARFI, FibroScan® (M probe for patients with BMI <30 kg/m(2), and XL probe for patients with BMI ⩾30 kg/m(2)), performed within two weeks of liver biopsy. Areas under the receiver operating curves (AUROCs) were performed and compared for each degree of liver fibrosis. RESULTS: SSI, FibroScan®, and ARFI correlated significantly with histological fibrosis score (r=0.79, p<0.00001; r=0.70, p<0.00001; r=0.64, p<0.00001, respectively). AUROCs of SSI, FibroScan®, and ARFI were 0.89, 0.86, and 0.84 for the diagnosis of mild fibrosis; 0.88, 0.84, and 0.81 for the diagnosis of significant fibrosis; 0.93, 0.87, and 0.89, for the diagnosis of severe fibrosis; 0.93, 0.90, and 0.90 for the diagnosis of cirrhosis, respectively. SSI had a higher accuracy than FibroScan® for the diagnosis of severe fibrosis (⩾F3) (p=0.0016), and a higher accuracy than ARFI for the diagnosis of significant fibrosis (⩾F2) (p=0.0003). No significant difference was observed for the diagnosis of mild fibrosis and cirrhosis. CONCLUSIONS: SSI is an efficient method for the assessment of liver fibrosis in chronic liver diseases, comparing favourably to FibroScan® and ARFI.

Locally advanced pancreatic adenocarcinoma: reassessment of response with CT after neoadjuvant chemotherapy and radiation therapy.

PURPOSE: To prospectively evaluate the utility of computed tomography (CT) for determination of tumor response and prediction of resectability after neoadjuvant combined chemotherapy and radiation therapy (CRT) in patients with nonmetastatic locally advanced pancreatic cancer. MATERIALS AND METHODS: This study received institutional review board approval, and all participants provided written informed consent. Consecutive patients with cephalic locally advanced pancreatic cancer who underwent surgical exploration and/or resection following neoadjuvant CRT were prospectively enrolled from June 2009 to May 2013. Two radiologists independently analyzed the baseline and post-CRT CT scans for the size, attenuation, and circumferential vascular contacts of the tumor. Associations between the postoperative histologic grade of the tumor response (pTNM) and the clinical, biologic, and CT criteria were assessed by using Spearman correlation coefficients. CT criteria related to the presence of complete (ie, R0) resection were assessed by using logistic regression. RESULTS: Forty-seven patients were included, 33 with an R0 resection and 14 with positive margins (ie, R1) or no resection. Variables demonstrating a significant correlation with the histologic tumor classification of tumor response were post-CRT carbohydrate antigen 19-9 level (r = 0.46), post-CRT largest tumor axis (r = 0.44), post-CRT sum of the largest and smallest tumor axes (r = 0.46), change in the largest axis (r = -0.31), change in the sum of the largest and smallest axes (r = -0.39), change in superior mesenteric vein (SMV) and/or portal vein (hereafter, SMV/portal vein) contact (r = -0.38), and post-CRT superior mesenteric artery contact (r = 0.34). Partial regression of tumor contact with the SMV/portal vein was associated in all cases with R0 resection (10 of 10 patients, positive predictive value = 100%), and partial regression of tumor contact with any peripancreatic vascular axis was associated with R0 resection in 91% of cases (20 of 22 patients, positive predictive value = 91%). Persistence of SMV/portal vein stenosis after CRT was not predictive of R1 resection. CONCLUSION: Partial regression of tumor-vessel contact indicates suitability for surgical exploration, irrespective of the degree of decrease in tumor size or the degree of residual vascular involvement.

MR relaxometry in chronic liver diseases: Comparison of T1 mapping, T2 mapping, and diffusion-weighted imaging for assessing cirrhosis diagnosis and severity.

BACKGROUND: MR relaxometry has been extensively studied in the field of cardiac diseases, but its contribution to liver imaging is unclear. We aimed to compare liver and spleen T1 mapping, T2 mapping, and diffusion-weighted MR imaging (DWI) for assessing the diagnosis and severity of cirrhosis. METHODS: We prospectively included 129 patients with normal (n=40) and cirrhotic livers (n=89) from May to September 2014. Non-enhanced liver T1 mapping, splenic T2 mapping, and liver and splenic DWI were measured and compared for assessing cirrhosis severity using Child-Pugh score, MELD score, and presence or not of large esophageal varices (EVs) and liver stiffness measurements using Fibroscan(®) as reference. RESULTS: Liver T1 mapping was the only variable demonstrating significant differences between normal patients (500±79ms), Child-Pugh A patients (574±84ms) and Child-Pugh B/C patients (690±147ms; all p-values <0.00001). Liver T1 mapping had a significant correlation with Child-Pugh score (Pearson's correlation coefficient of 0.46), MEDL score (0.30), and liver stiffness measurement (0.52). Areas under the receiver operating characteristic curves of liver T1 mapping for the diagnosis of cirrhosis (O.85; 95% confidence intervals (CI), 0.77-0.91), Child-Pugh B/C cirrhosis (0.87; 95%CI, 0.76-0.93), and large EVs (0.75; 95%CI, 0.63-0.83) were greater than that of spleen T2 mapping, liver and spleen DWI (all p-values<0.01). CONCLUSION: Liver T1 mapping is a promising new diagnostic tool for assessing cirrhosis diagnosis and severity, showing higher diagnostic accuracy than liver and spleen DWI, while T2 mapping is not reliable.

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.