Magnetic resonance quantification of water and metabolites in the brain of cirrhotics following induced hyperammonaemia

Multimodality MR Imaging Findings of Low-Grade Brain Edema in Hepatic Encephalopathy

“…Hyperammonia can account for the MR spectroscopy findings in patients with cirrhosis. One recent study 32 of induced hyperammonemia in patients with cirrhosis…”

“…This reversibility of 1 H-MR spectroscopy abnormalities precedes the disappearance of pallidal hyperintensity after liver transplantation and correlates with improvements in the neurologic manifestations of HE. 32,35 However, 1 H-MR spectroscopy abnormalities can also be detected in patients with abnormal liver function after liver transplantation.…”

Identification of Minimal Hepatic Encephalopathy in Patients with Cirrhosis Based on White Matter Imaging and Bayesian Data Mining

“…WM edema, which could be extracellular and/or cytotoxic in origin, [8][9][10] is considered closely associated with a metabolic disorder of ammonia in the brain tissue of patients with MHE. 7,8,10,30 Although the neuropathologic mechanism of decreased FA is not well-understood in the setting of cirrhosis, one possible explanation is demyelination. Osmotic demyelination (due to inappropriate correction of hyponatremia 31 ) has been noted in cirrhosis.…”

Ammonia and cerebral water. Importance of structural analysis of the brain in hepatic encephalopathy

“…To the Editor: We thank McPhail et al [1] for their comments regarding our paper [2] in which we reported that induced hyperammonaemia in patients with hepatic encephalopathy (HE) leads to a transient increase in brain water apparent diffusion coefficient (ADC) reported from diffusion tensor imaging (DTI), accompanied by a decrease in frontal white matter myo-inositol (mI) measured by proton magnetic resonance spectroscopy (MRS). McPhail et al…”

“…We read with interest the article by Mardini and colleagues [1], who induced hyperammonaemia experimentally in patients with cirrhosis. They show an increase in apparent diffusion coefficient (ADC) reported on diffusion tensor MR imaging (DTI) of the brain and a decrease in frontal white matter (FWM) myo-inositol (mI) demonstrated on concurrent 1 H MR spectroscopy (MRS).…”