Portal hypertension correlates with splenic stiffness as measured with MR elastography

Abstract

Purpose To investigate the correlation between MRE assessed spleen stiffness and direct portal vein pressure gradient (D-HVPG) measurements in a large animal model of portal hypertension. Materials and Methods Cholestatic liver disease was established in adult canines by common bile duct ligation. A spin echo based EPI MRE sequence was used to acquire 3-D/3-axis abdominal MRE data at baseline, four weeks, and eight weeks. Liver biopsies, blood samples, and D-HVPG measurements were obtained simultaneously. Results Animals developed portal hypertension (D-HVPG: 11.0±5.1 mmHg) with only F1 fibrosis after four weeks. F3 fibrosis was confirmed after eight weeks despite no further rise in portal hypertension (D-HVPG: 11.3±3.2 mmHg). Mean stiffnesses of the spleen increased over two-fold from baseline (1.72±0.33 kPa) to four weeks (3.54±0.31 kPa), and stabilized at eight weeks (3.38±0.06 kPa) in a pattern consistent with changes in portal pressure. A positive correlation was observed between spleen stiffness and D-HVPG (r2 = 0.86, p<0.01). Conclusion These findings indicate a temporal relationship between portal hypertension and the development of liver fibrosis in a large animal model of cholestatic liver disease. The observed direct correlation between spleen stiffness and D-HVPG suggest a non-invasive MRE approach to diagnose and screen for portal hypertension.

Patient-Activated Three-Dimensional Multifrequency Magnetic Resonance Elastography for High-Resolution Mechanical Imaging of the Liver and Spleen

“…Similar statistically significant differences were found for φ, which was higher in the spleen (0.607 ± 0.152) than in the liver (0.407 ± 0.044, p = 0.0008), again with a higher intrasplenic heterogeneity (SD = 0.204 ± 0.034 [liver] vs. 0.282 ± 0.076 [spleen], p = 0.0084). Similar to previous studies [24,33], we found a significant correlation between |G * | of the liver and spleen (p = 0.046), while φ was not correlated in the two organs, as has been reported in [14].…”

“…We use this enhanced elastodynamic information to produce mechanical parameter maps which display details of the abdomen including the liver and the spleen with fewer artifacts than previous methods. This methodological improvement is intended to provide the methodological background for a precise mechanical characterization of abdominal tissue in different clinical applications such as the assessment of lesions, staging of heterogeneous hepatic fibrosis, or detection of a vascular pressure imbalance, which may influence the elasticity ratio between the liver and spleen [24].…”

MR Elastography for the Assessment of Hepatic Fibrosis in Patients with Chronic Hepatitis B Infection: Does Histologic Necroinflammation Influence the Measurement of Hepatic Stiffness?

“…MR elastography is increasingly being used clinically as a noninvasive method to stage hepatic fibrosis (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25). However, MR elastography studies in patients with homogeneous HBV infection or direct comparative studies between HBV and HCV are rare (26)(27)(28)(29).…”

Diagnostic imaging modalities

“…It is more frequently observed in patients with viral cirrhosis and PBC than in patients with alcoholic cirrhosis. The usefulness of splenic stiffness measurements obtained using MR elastography for detecting significant portal hypertension has recently been tested [85]. Along with splenomegaly, Gamna-Gandy bodies are usually found in the spleen of cirrhotic patients on gradient-echo MRI.…”