Segmental liver hyperintensity in malignant biliary obstruction on diffusion weighted MRI: associated MRI findings and relationship with serum alanine aminotransferase levels

Abstract

Objectives: Segmental liver hyperintensity can be observed in malignant biliary obstruction on diffusion weighted MRI (DW-MRI). We describe MRI findings associated with this sign and evaluate whether DW-MRI segmental hyperintensity has any relationship with serum alanine aminotransferase (ALT) levels. Methods: The DW-MRI T 1 weighted, T 2 weighted and gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA)-enhanced T 1 weighted images obtained in 21 patients with hepatic malignancy, who demonstrated biliary obstruction and segmental hyperintensity on DW-MRI (b50-750 s mm -2 ), were retrospectively reviewed by 2 readers blinded to clinical results. DW-MRI hyperintense liver segments were recorded as hypointense, isointense or hyperintense relative to normal liver on T 1 /T 2 weighted imaging. It was also noted whether contrast enhancement was similar to that observed in normal liver or diminished in the hepatocellular phase. The mean apparent diffusion coefficient (ADC) value (610 23 s mm -2 ) of DW-MRI hyperintense segments, normal liver and tumour were compared using Student's t-test. The frequency of MRI findings was corroborated with serum ALT levels, which reflect hepatocyte injury. Results: DW-MRI hyperintense segments frequently showed T 1 hyperintensity (10/21), T 2 hyperintensity (19/21) and/or diminished contrast enhancement (15/21). Tumours showed significantly lower mean ADC values than liver (1.23¡0.08 vs 1.43¡0.05; p50.013). Segments showing concomitant T 1 hyperintensity had lower mean ADC values than liver (1.30¡0.05 vs 1.43¡0.05; p50.023). The patients (8/10) with concomitant T 1 and DW-MRI segmental hyperintensity showed elevated ALT levels (p50.030, Fisher's exact test). Conclusion: Concomitantly high T 1 weighted and DW-MRI signal in liver segments was associated with lower ADC values and abnormal liver function tests, which could reflect underlying cellular swelling and damage.

Assessing liver function in patients with HBV-related HCC: a comparison of T1 mapping on Gd-EOB-DTPA-enhanced MR imaging with DWI

“…They reported that ADC values were not predictive of postoperative insufficiency in liver function, including persistent hyperbilirubinemia (total bilirubin level >5 mg/dl for more than five days after surgery) and postoperative death, in the absence of other causes in patients with HBV-related HCC. However, Tam et al [6] showed that lower segmental ADC values may be associated with abnormal liver function in patients with malignant biliary obstruction. This may have been largely due to the fact that the patients in their study suffered severe segmental liver dysfunction which was already depicted on high-B-value DW (segmental hyperintensity) and T 2 -weighted images (dilatation of the bile duct).…”

“…Diffusion-weighted imaging (DWI) and magnetic resonance imaging (MRI) using gadoxetic acid (Gd-EOB-DTPA) have recently shown promise for the evaluation of segmental liver functional reserve [6][7][8][9][10][11]. DWI is based on the random Brownian motion of water molecules within the voxel.…”

“…Changes in hepatic diffusion are indicative of tissue changes on a cellular level, and may be used to assess liver function through the use of apparent diffusion coefficient (ADC) mapping. A previous study showed that ADC values could reflect underlying cellular swelling and damage, which may be useful for identifying patients at risk of hepatocellular impairment from biliary obstruction [6]. However, Kim et al [12] reported that DWI-ADC was not suitable for predicting postoperative hepatic insufficiency, advanced liver fibrosis, or cirrhosis in patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC).…”

Assessment of Hepatic Function with Gd-EOB-DTPA-Enhanced Hepatic MRI

“…For instance, regional variations in hepatic parenchymal tissue composition and nodularity can be readily depicted on hepatic magnetic resonance (MR) images [12,13]. In addition, studies have reported the appropriate characterization of hepatic parenchymal properties using functional MR techniques including MR spectroscopy [14,15], MR elastography [16], diffusion-weighted imaging [17], MR relaxometry [18], and Gd-EOB-DTPA-enhanced MRI [19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43]. In this article, we will review and discuss recently published studies that used Gd-EOB-DTPA-enhanced hepatic MRI to evaluate hepatic function.…”

Pitfalls in Gd‐EOB‐DTPA–Enhanced Liver Magnetic Resonance Imaging With an Emphasis on Nontumorous Lesions

“…). The corresponding area appears hyperintense on both T 1 ‐ and T 2 ‐weighted images because of the accumulation of paramagnetic materials (e.g., iron, copper, and manganese ions) . Arterial enhancement can be accompanied in the corresponding area of bile duct obstruction.…”