Non-invasive assessment of hepatic steatosis in patients with NAFLD using controlled attenuation parameter and 1H-MR spectroscopy

• Published in: PloS one 2014, Vol.9 (3), p.e91987-e91987
• Main Authors: Karlas, Thomas, Petroff, David, Garnov, Nikita, Böhm, Stephan, Tenckhoff, Hannelore, Wittekind, Christian, Wiese, Manfred, Schiefke, Ingolf, Linder, Nicolas, Schaudinn, Alexander, Busse, Harald, Kahn, Thomas, Mössner, Joachim, Berg, Thomas, Tröltzsch, Michael, Keim, Volker, Wiegand, Johannes
• Format: Article
• Language: English
• Subjects: Adult; Aged; Anthropometry; Attenuation; Biopsy; Case-Control Studies; Comorbidity; Correlation; Dermatology; Diabetes; Diagnostic systems; Disease control; Elasticity Imaging Techniques; Fatty liver; Female; Fibrosis; Gastroenterology; Hepatitis; Hepatocytes; Hepatology; Histopathology; Hospitals; Humans; Laboratories; Liver; Liver - metabolism; Liver - pathology; Liver Cirrhosis - pathology; Liver diseases; Magnetic resonance; Magnetic resonance spectroscopy; Magnetic Resonance Spectroscopy - methods; Male; Medical imaging; Medicine; Medicine and Health Sciences; Methods; Middle Aged; Neurology; NMR; Non-alcoholic Fatty Liver Disease - diagnosis; Nuclear magnetic resonance; Patients; Physical Sciences; Quality; Reproducibility of Results; Rheumatology; Sensitivity and Specificity; Spectroscopy; Spectrum analysis; Steatosis; Strapping; Studies; Ultrasonic imaging; Ultrasound
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0091987

Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). 1H-Magnetic resonance spectroscopy (1H-MRS) and the ultrasound-based controlled attenuation parameter (CAP) correlate with biopsy proven steatosis, but have not been correlated with each other so far. We therefore performed a head-to-head comparison between both methods. Fifty patients with biopsy-proven NAFLD and 15 healthy volunteers were evaluated with 1H-MRS and transient elastography (TE) including CAP. Steatosis was defined according to the percentage of affected hepatocytes: S1 5-33%, S2 34-66%, S3 ≥67%. Steatosis grade in patients with NAFLD was S1 36%, S2 40% and S3 24%. CAP and 1H-MRS significantly correlated with histopathology and showed comparable accuracy for the detection of hepatic steatosis: areas under the receiver-operating characteristics curves were 0.93 vs. 0.88 for steatosis ≥S1 and 0.94 vs. 0.88 for ≥S2, respectively. Boot-strapping analysis revealed a CAP cut-off of 300 dB/m for detection of S2-3 steatosis, while retaining the lower cut-off of 215 dB/m for the definition of healthy individuals. Direct comparison between CAP and 1H-MRS revealed only modest correlation (total cohort: r = 0.63 [0.44, 0.76]; NAFLD cases: r = 0.56 [0.32, 0.74]). For detection of F2-4 fibrosis TE had sensitivity and specificity of 100% and 98.1% at a cut-off value of 8.85 kPa. Our data suggest a comparable diagnostic value of CAP and 1H-MRS for hepatic steatosis quantification. Combined with the simultaneous TE fibrosis assessment, CAP represents an efficient method for non-invasive characterization of NAFLD. Limited correlation between CAP and 1H-MRS may be explained by different technical aspects, anthropometry, and presence of advanced liver fibrosis.