Original Article
Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Nov 7, 2009; 15(41): 5157-5164
Published online Nov 7, 2009. doi: 10.3748/wjg.15.5157
Voxel-based analyses of magnetization transfer imaging of the brain in hepatic encephalopathy
Falk R Miese, Hans-Jörg Wittsack, Gerald Kircheis, Arne Holstein, Christian Mathys, Ulrich Mödder, Mathias Cohnen
Falk R Miese, Hans-Jörg Wittsack, Arne Holstein, Christian Mathys, Ulrich Mödder, Mathias Cohnen, Institute of Radiology, University Hospital Düsseldorf, MNR Clinic, Moorenstrasse 5, Düsseldorf 40225, Germany
Gerald Kircheis, Department of Internal Medicine, Division of Gastroenterology, Hepatology and Infectious Diseases, University Hospital Düsseldorf, Moorenstrasse 5, Düsseldorf 40225, Germany
Author contributions: Miese FR, Wittsack HJ, Kircheis G, Holstein A, Mödder U and Cohnen M designed the research; Miese FR, Wittsack HJ, Kircheis G and Mathys C performed the research; Miese FR, Wittsack HJ and Holstein A analyzed the data; Miese FR wrote the paper.
Correspondence to: Dr. Falk R Miese, Institute of Radiology, University Hospital Düsseldorf, MNR Clinic, Moorenstrasse 5, Düsseldorf 40225, Germany. dr.miese@gmx.de
Telephone: +49-211-8117752 Fax: +49-211-8116145
Received: May 27, 2009
Revised: August 3, 2009
Accepted: August 10, 2009
Published online: November 7, 2009
Abstract

AIM: To evaluate the spatial distribution of cerebral abnormalities in cirrhotic subjects with and without hepatic encephalopathy (HE) found with magnetization transfer imaging (MTI).

METHODS: Nineteen cirrhotic patients graded from neurologically normal to HE grade 2 and 18 healthy control subjects underwent magnetic resonance imaging. They gave institutional-review-board-approved written consent. Magnetization transfer ratio (MTR) maps were generated from MTI. We tested for significant differences compared to the control group using statistical non-parametric mapping (SnPM) for a voxel-based evaluation.

RESULTS: The MTR of grey and white matter was lower in subjects with more severe HE. Changes were found in patients with cirrhosis without neurological deficits in the basal ganglia and bilateral white matter. The loss in magnetization transfer increased in severity and spatial extent in patients with overt HE. Patients with HE grade 2 showed an MTR decrease in white and grey matter: the maximum loss of magnetization transfer effect was located in the basal ganglia [SnPM (pseudo-)t = 17.98, P = 0.0001].

CONCLUSION: The distribution of MTR changes in HE points to an early involvement of basal ganglia and white matter in HE.

Keywords: Brain, Hepatic encephalopathy, Magnetic resonance imaging, Liver cirrhosis, Magnetization transfer imaging