Magnetic resonance elastography is superior to acoustic radiation force impulse for the Diagnosis of fibrosis in patients with biopsy‐proven nonalcoholic fatty liver disease: A prospective study

Abstract

Magnetic resonance elastography (MRE), an advanced MR-based imaging technique, and acoustic radiation force impulse (ARFI), an ultrasound-based imaging technique, have been shown to be accurate for diagnosing nonalcoholic fatty liver disease (NAFLD) fibrosis. However, no head-to-head comparisons between MRE and ARFI for diagnosing NAFLD fibrosis have been performed. We aimed to compare MRE versus ARFI head-to-head for diagnosing fibrosis in well-characterized patients with biopsy-proven NAFLD. Methods This cross-sectional analysis of a prospective cohort involved 125 patients (54.4% female) who underwent MRE, ARFI, and contemporaneous liver biopsies scored using the Nonalcoholic Steatohepatitis Clinical Research Network histological scoring system. MRE versus ARFI’s performances for diagnosing fibrosis were evaluated using area under receiver operating characteristic curves (AUROCs). Results The mean (±SD) age and BMI were 48.9 (±15.4) years and 31.8 (±7.0) kg/m2, respectively. For diagnosing any fibrosis (≥ stage 1), MRE’s AUROC was 0.799 (95% CI, 0.723–0.875), significantly (p=0.012) higher than ARFI’s AUROC of 0.664 (95% CI, 0.568–0.760). In stratified analysis by presence/absence of obesity, MRE was superior to ARFI for diagnosing any fibrosis in obese patients (p<0.001) but not in non-obese patients (p=0.722). MRE’s AUROCs for diagnosing ≥ stages 2, 3, and 4 fibrosis were 0.885 (95% CI, 0.816–0.953), 0.934 (95% CI, 0.863–1.000), and 0.882 (95% CI, 0.729–1.000), and ARFI’s AUROCs were 0.848 (95% CI, 0.776–0.921), 0.896 (95% CI, 0.824–0.968), and 0.862 (95% CI, 0.721–1.000). MRE had higher AUROCs than ARFI for discriminating dichotomized fibrosis stages at all dichotomization cut-points, but the AUROC differences decreased as the cut-points (fibrosis stages) increased. Conclusions MRE is more accurate than ARFI for diagnosing any fibrosis in all NAFLD patients and obese NAFLD patients, although not in non-obese NAFLD patients.

Imaging-Based Assessment of Steatosis, Inflammation and Fibrosis in NAFLD

“…Overall, SSI performed best for the detection of significant fibrosis, advanced fibrosis and cirrhosis (AUROCs 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) [45••]. The results are similar to prior individual studies [39,55]. It appears that none of the three imaging methods could accurately predict < F2 fibrosis, so further optimization of ultrasound techniques is needed [45••].…”

Nonalcoholic fatty liver disease with cirrhosis increases familial risk for advanced fibrosis

“…Participants were considered to have NAFLD-related cirrhosis if they had NAFLD according to the definition above and had biopsy-proven cirrhosis (histology fibrosis stage 4). We have previously validated that a liver stiffness cut point greater than 3.63 kPa on MRE provides an accuracy of 0.92 for the detection of advanced fibrosis, and it is the most accurate noninvasive test for the diagnosis of advanced fibrosis (29,(37)(38)(39). Advanced fibrosis among first-degree relatives was determined by either imaging evidence of nodularity and presence of intraabdominal varices or other imaging evidence of portal hypertension or liver stiffness assessment with MRE threshold ≥3.63 kPa (28,29,34).…”

Elastography in Chronic Liver Disease: Modalities, Techniques, Limitations, and Future Directions

“…The high accuracy is probably related to the large volume of parenchymal sampling, with the potential to assess the stiffness of nearly the entire liver parenchyma. The technique also has high technical success, providing reliable examinations even in obese patients and in those with hepatic steatosis (59,63,64). After the required hardware has been set up, MR elastography may be added to any routine MR imaging protocol with only a few minutes of additional imaging time.…”