Evaluation of hepatic fibrosis: a review from the society of abdominal radiology disease focus panel

Abstract

Hepatic fibrosis is potentially reversible; however early diagnosis is necessary for treatment in order to halt progression to cirrhosis and development of complications including portal hypertension and hepatocellular carcinoma. Morphologic signs of cirrhosis on ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) alone are unreliable and are seen with more advanced disease. Newer imaging techniques to diagnose liver fibrosis are reliable and accurate, and include magnetic resonance elastography and US elastography (one-dimensional transient elastography and point shear wave elastography or acoustic radiation force impulse imaging). Research is ongoing with multiple other techniques for the noninvasive diagnosis of hepatic fibrosis, including MRI with diffusion-weighted imaging, hepatobiliary contrast enhancement, and perfusion; CT using perfusion, fractional extracellular space techniques, and dual-energy, contrast-enhanced US, texture analysis in multiple modalities, quantitative mapping, and direct molecular imaging probes. Efforts to advance the noninvasive imaging assessment of hepatic fibrosis will facilitate earlier diagnosis and improve patient monitoring with the goal of preventing the progression to cirrhosis and its complications.

Keywords: Chronic liver disease; Elastography; Fibrosis; Magnetic resonance imaging; Perfusion; Sonography.

Fig. 1

a–f Morphologic imaging features of cirrhosis in 6 patients. A) Ultrasound shows a nodular surface (arrow) and coarsened echotexture (*). MRI images of cirrhotic livers show B) a nodular surface contour, hypertrophy of lateral left lobe (*), and expanded hilar periportal space (arrow) on post contrast T1 FS sequence, C) atrophic right hepatic lobe (arrow) on axial T2 Half Fourier Acquisition Single Shot Turbo Spin Echo (HASTE) sequence, D) hypertrophy of caudate lobe on post contrast T1 FS sequence (arrow), E) expanded gallbladder fossa and atrophic medial segment left lobe on post contrast T1 FS sequence (arrow). F) Postcontrast CT in the portal venous phase shows a right hepatic posterior “notch” (arrow)

Fig. 2

a–b Ultrasound of a 61-year-old woman with HIV and hepatitis C presenting for fibrosis screening shows potentially treatable liver fibrosis on ARFI prior to morphologic changes on grayscale ultrasound. A) Grayscale ultrasound of the right hepatic lobe shows a normal smooth echotexture. B) ARFI shows a shear wave velocity of 1.79 m/s (F3)

Fig. 3

a–b Bands of linear hepatic fibrosis on MRI are A) T2 hyperintense on T2 FS sequence and B) show delayed enhancement

Fig. 4

a–d 57-year-old man with fatty liver disease. Hepatic steatosis is seen with signal loss on the opposed phase imaging relative to the in phase images (A and B), but with normal liver morphology on T1 and T2-weighted imaging (A–C). D) MR elastography shows unsuspected cirrhosis (stiffness 7.5 kPa), making biopsy unnecessary

Fig. 5

a–b ADC maps from MRI with DWI show lower ADC in a cirrhotic patient (A) compared with a patient without chronic liver disease (B)

Fig. 6

a–b MRI using hepatobiliary contrast shows that on the hepatocyte phase, there is decreased liver enhancement of a cirrhotic liver (A) compared with a noncirrhotic liver (B)