Repeatability of magnetic resonance elastography for quantification of hepatic stiffness

Abstract

Purpose: To determine the sources of variability of MRE hepatic stiffness measurements using healthy volunteers and patients and to calculate the minimum change required for statistical significance. Hepatic stiffness measured with magnetic resonance elastography (MRE) has demonstrated tremendous potential as a noninvasive surrogate of hepatic fibrosis, although the underlying repeatability of MRE for longitudinal tracking of liver disease has not been documented. Materials and Methods:MRE stiffness measurements from 20 healthy volunteers and 10 patients were obtained twice on the same day, and repeated 2-4 weeks later for volunteers in this institutional review board-approved study. A linear mixed effects model was used to estimate the component sources of variability in the data. Results:The standard deviation of MRE measurements of the same individual on different days is 11.9% (percent of the measured stiffness) using the same reader and 12.0% using different readers. The standard deviation of the difference between two measurements (i.e., longitudinal change in an individual) is 17.4%; the corresponding 95% confidence interval for zero change is (À27.0%, 37.0%).Conclusion: MRE is a repeatable method for quantifying liver stiffness. Using the described MRE technique, changes greater than 37.0% of the smaller measured stiffness value represent meaningful changes in longitudinal liver stiffness measurements.

Non-Invasive Diagnostic and Prognostic Evaluation of Liver Cirrhosis and Portal Hypertension

“…It has been tested in human subjects, and the preliminary results support its practicability in predicting the stage of fibrosis in patients with chronic liver disease [74]. MRE is repeatable and changes correlate well with changes in tissue fibrosis [75]. MRE has been successfully applied to measure spleen stiffness, which was highly correlated with hepatic stiffness and might have a closer correlation with portal pressure [76].…”

Magnetic Resonance Elastography for Staging Liver Fibrosis in Chronic Hepatitis C

“…8 Magnetic resonance (MR) elastography (MRE) was developed as a noninvasive method for measuring liver stiŠness and is currently used primarily for staging liverˆbrosis in the clinical setting. Though its su‹cient reproducibility [9][10][11] and high diagnostic ability for staging liverˆbrosis are reported, 12 previous studies of liver MRE have included cases of hepaticˆbrosis of various causes, including type B and C viral hepatitis and alcoholic hepa- 15 For example, pericellularˆbrosis is a distinguishing feature of alcoholic hepatitis,while periportal degeneration andˆbrosis is believed to be more prominant in type C viral hepatitis than alcoholic hepatitis. 16 Focal necrosis and in‰ammatory cell inˆltration are also believed to be more advanced in type B than type C viral hepatitis.…”

MR-based Measurements of Portal Vein Flow and Liver Stiffness for Predicting Gastroesophageal Varices

“…[11][12][13][14][15] MR elastography (MRE) is a state-ofthe-art tool for evaluating liver stiŠness that oŠers high reproducibility, repeatability, and validity. [16][17][18][19][20][21] MR examination of the liver can be shortened by performing both PC-MRI and MRE during the delay before equilibrium-or hepatocyte-phase after administration of a contrast agent. 22,23 Use of these examinations to predict GEV would signiˆcantly enhance the utility of MR imaging in managing patients with cirrhosis.…”