Current and future applications of magnetic resonance imaging and spectroscopy of the brain in hepatic encepha-lopathy

作     者：VP Bob Graver M Alex Dresner Daniel M Forton Serena Counsell David J Larkman Nayna Patel Howard C Thomas Simon D Taylor-Robinson 

作者机构：Hepatology Section Division of Medicine ASt Mary's CampusFaculty of MedicineImperial College LondonSouth Wharf StreetLondon W2 1NYUnited Kingdom Imaging Sciences DepartmentClinical Sciences DivisionFaculty of MedicineImperial College LondonHammersmith HospitalDu Cane RoadLondon W12 0HSUnited Kingdom Imaging Sciences Department Clinical Sciences DivisionFaculty of MedicineImperial College LondonHammersmith HospitalDu Cane RoadLondon W12 0HSUnited Kingdom Hepatology Section Division of Medicine ASt Mary's CampusFaculty of MedicineImperial College LondonSouth Wharf StreetLondon W2 1NYUnited Kingdom 

出 版 物：《World Journal of Gastroenterology》 (世界胃肠病学杂志（英文版）)

年 卷 期：2006年第12卷第19期

页      面：2969-2978页

核心收录：

学科分类：1002[医学-临床医学] 100204[医学-神经病学] 10[医学] 

基　　金：Supported by grants from BUPA  the Royal College of Physicians of London and Paddington Charitable Trust  St Mary's London. The European Association for the Study of the Liver  the British Medical Research Council (G9900178)Philips Medical Systems (Cleveland  Ohio  USA) and the United Kingdom Department of Health provided support for some of the studies outlined 

主　　题：Hepatic encephalopathy Magnetic resonance imaging Magnetic resonance spectroscopy Diffusion weighted imaging Arterial spin labeling Functional MRI 

摘      要：Hepatic encephalopathy （HE） is a common neuropsychiatric abnormality, which complicates the course of patients with liver disease and results from hepatocellular failure and/or portosystemic shunting. The manifestations of HE are widely variable and involve a spectrum from mild subclinical disturbance to deep coma. Research interest has focused on the role of circulating gut-derived toxins, particularly ammonia, the development of brain swelling and changes in cerebral neurotransmitter systems that lead to global CNS depression and disordered function. Until recently the direct investigation of cerebral function has been difficult in man. However, new magnetic resonance imaging （MRI） techniques provide a non-invasive means of assessment of changes in brain volume （coregistered MRI） and impaired brain function （fMRI）, while proton magnetic resonance spectroscopy （^1H MRS） detects changes in brain biochemistry, including direct measurement of cerebral osmolytes, such as myoinositol, glutamate and glutamine which govern processes intrinsic to cellular homeostasis, including the accumulation of intracellular water. The concentrations of these intracellular osmolytes alter with hyperammonaemia. MRS-detected metabolite abnormalities correlate with the severity of neuropsychiatric impairment and since MR spectra return towards normal after treatment, the technique may be of use in objective patient monitoring and in assessing the effectiveness of various treatment regimens.