BACKGROUND: Hepatic fibrosis is a dynamic, reversible process which can result in liver failure. Diagnosis and monitoring of hepatic fibrosis are clinically important.
PURPOSE: To compare the diagnostic performance of diffusion kurtosis imaging (DKI), intravoxel incoherent motion (IVIM), and monoexponential diffusion-weighted imaging (DWI) to detect clinically significant fibrosis (≥ F2).
MATERIAL AND METHODS: This retrospective study was approved by Institutional Review Board and the requirement of informed consent was waived. One hundred and six patients were included who underwent liver multiple b-value DWI (10 b-values at 0-1000 s/mm2) at 1.5 T and were histologically diagnosed with hepatic fibrosis. Apparent diffusion coefficient (ADC), DKI-derived apparent kurtosis ( Kapp) and diffusivity ( Dapp), and IVIM-derived true diffusion ( Dt), pseudodiffusion ( D*), and perfusion fraction ( f) were compared between no or early fibrosis (F0-1, n = 19) and clinically significant fibrosis (≥ F2, n = 87). Diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis.
RESULTS: F2-4 had a significantly lower D* (59.9±16.3 vs. 86.2±21.0 [×10-3 mm2/s]) and Dapp (3.46±0.79 vs. 4.07 ± 0.76 [×10-3 mm2/s]) but higher Kapp (1.10±0.18 vs. 0.98±0.12) than F0-1 ( P < 0.01). ADC, Dt, and f did not show significant difference between two groups ( P > 0.05). The area under the ROC curve for diagnosis of clinically significant fibrosis (≥ F2) was significantly larger in D* (0.89; 95% CI = 0.81-0.94) than Dapp (0.73; 95% CI = 0.63-0.81) and Kapp (0.75; 95% CI = 0.65-0.83) ( P = 0.017 and 0.012, respectively).
CONCLUSION: IVIM-DWI might be more suitable for detecting hepatic fibrosis than the monoexponential and kurtosis model, and D* showed a better diagnostic performance to detect clinically significant fibrosis than other parameters.