• 1
    Adams RD, Foley MF. The neurological disorder associated with liver disease. In: MerrittHH, HareCC, eds. Metabolic and Toxic Diseases of the Nervous System. Baltimore: Williams & Wilkins, 1953: 198237.
  • 2
    Gilberstadt SJ, Gilberstadt H, Zieve L, Buegel B, Collier RO, Mc Clain J. Psychomotor performance defects in cirrhotic patients without overt encephalopathy. Arch Intern Med 1980; 140: 519521.
  • 3
    Tarter RE, Hegedus AM, Van Thiel DH, Schade RR, Gavaler JS, Starzl TE. Nonalcoholic cirrhosis associated with neuropsychological dysfunction in the absence of overt evidence of hepatic encephalopathy. Gastroenterology 1984; 86: 14211427.
  • 4
    Weissenborn K, Burchert W, Bokemeyer M, Ehrenheim C, Kolbe H, Manns MP, et al. Regional differences of cerebral glucose metabolism in patients with liver cirrhosis depending on the grade of portosystemic encephalopathy (PSE). In: RecordC, Al MardiniH, eds. Advances in Hepatic Encephalopathy and Metabolism in Liver Disease. Newcastle upon Tyne, England: Medical Faculty University Newcastle upon Tyne, 1997: 359363.
  • 5
    Lockwood AH, Murphy BW, Donnelly KZ, Mahl TC, Perini S. Positron-emission tomographic localization of abnormalities of brain metabolism in patients with minimal hepatic encephalopathy. HEPATOLOGY 1993; 18: 10611068.
  • 6
    Lockwood AH, Weissenborn K, Bokemeyer M, Tietge U, Burchert W. Correlations between cerebral glucose metabolism and neuropsychological test performance in non-alcoholic cirrhotics. Metab Brain Dis 2002; 17: 2940.
  • 7
    Butterworth RF. Alterations of neurotransmitter-related gene expression in human and experimental portal-systemic encephalopathy. Metab Brain Dis 1998; 13: 337349.
  • 8
    Jones EA, Basile AS. Does ammonia contribute to increased GABA-ergic neurotransmission in liver failure? Metab Brain Dis 1998; 13: 351360.
  • 9
    Norenberg MD. Astroglial dysfunction in hepatic encephalopathy. Metab Brain Dis 1998; 13: 319335.
  • 10
    Ahl B, Fischer-Wasels D, van den Hoff J, Burchert W, Weissenborn K. Cerebral ammonia-, H2O- and Glucose-PET in cirrhotics with minimal hepatic encephalopathy (HE) [Abstract]. J Hepatol 2000; 32(Suppl2): 146.
  • 11
    Pugh RN, Murray-Lyon IM, Dawson JL, Pietroni MC, Will R. Transection of the oesophagus for bleeding oesophageal varices. Brit J Surg 1973; 60: 646649.
  • 12
    Weissenborn K, Ennen J, Ruckert N, Schomerus H, Dengler R, Manns MP, et al. The PSE-test: an attempt to standardize neuropsychological assessment of latent portosystemic encephalopathy (PSE). In: RecordC, Al MardiniH, eds. Advances in Hepatic Encephalopathy and Metabolism in Liver Disease. Newcastle upon Tyne, England: Medical Faculty University Newcastle upon Tyne, 1997: 489494.
  • 13
    Schomerus H, Weissenborn K, Hamster W, Rueckert N, Hecker H. PSE-Syndrom-Test. Psychodiagnostisches Verfahren zur quantitativen Erfassung der (minimalen) portosystemischen Enzephalopathie. Frankfurt: Swets Test Services; 1999.
  • 14
    Ferenci P, Lockwood AH, Mullen K, Tarter R, Weissenborn K, Blei AT. Hepatic encephalopathy—definition, nomenclature, diagnosis, and quantification: final report of the working party at the 11th World Congress of Gastroenterology, Vienna 1998. HEPATOLOGY 2002; 35: 716721.
  • 15
    Conn HO, Lieberthal MM. The Hepatic Coma Syndromes and Lactulose. Baltimore: Williams & Wilkins; 1979.
  • 16
    van den Hoff J, Burchert W, Muller-Schauenburg W, Meyer GJ, Hundeshagen H. Accurate local blood flow measurements with dynamic PET: fast determination of input function delay and dispersion by multilinear minimization. J Nucl Med 1993; 34: 17701777.
  • 17
    Hutchins GD, Schwaiger M, Rosenspire KC, Krivokapich J, Schelbert H, Kuhl DE. Noninvasive quantification of regional blood flow in the human heart using N-13-ammonia and dynamic positron emission tomographic imaging. J Am Coll Cardiol 1990; 15: 10321042.
  • 18
    Lockwood AH, McDonald JM, Reiman RE, Gelbard AS, Laughlin JS, Duffy TE, et al. The dynamics of ammonia metabolism in man: effects of liver disease and hyperammonia. J Clin Invest 1979; 63: 449460.
  • 19
    Lockwood AH, Bolomey L, Napoleon F. Blood-brain barrier to ammonia in humans. J Cereb Blood Flow Metab 1984; 4: 516522.
  • 20
    Blomqvist G. On the construction of functional maps in positron emission tomography. J Cereb Blood Flow Metab 1984; 4: 629632.
  • 21
    Rosenspire KC, Schwaiger M, Manger TJ, Hutchins GD, Sutorik A, Kuhl DE. Metabolic fate of [13N] ammonia in human and canine blood. J Nucl Med 1990; 31: 163167.
  • 22
    Patlak C, Blasberg RG, Fenstermacher JD. Graphical evaluation of blood-to-brain transfer constants from multiple-time uptake data. J Cereb Blood Flow Metab 1983; 3: 17.
  • 23
    Talairach J, Tournoux P. Co-planar Stereotaxic Atla of the Human Brain. 2nd ed. Stuttgart: Thieme Verlag; 1988.
  • 24
    Holm S. A simple sequentially rejective multiple test procedure. Scand J Statist 1979; 6: 6570.
  • 25
    Lockwood AH, Yap EWH, Wong WH. Cerebral ammonia metabolism in patients with severe liver disease and minimal hepatic encephalopathy. J Cereb Blood Flow Metab 1991; 11: 337341.
  • 26
    Lockwood AH. Hepatic Encephalopathy. Stoneham, UK: Butterworth-Heinemann; 1992.
  • 27
    Lockwood AH, Yap EW, Rhoades HM, Wong WH. Altered cerebral blood flow and glucose metabolism in patients with liver disease and minimal encephalopathy. J Cereb Blood Flow Metab 1991; 11: 331336.
  • 28
    Norenberg MD. A light and electron microscopic study of experimental portal-systemic (ammonia) encephalopathy. Lab Invest 1977; 36: 618627.
  • 29
    Haussinger D, Laubenberger J, vom Dahl S, Ernst T, Bayer S, Langer M, et al. Proton magnetic resonance spectroscopy studies on human brain myo-inositol in hypo-osmolarity and hepatic encephalopathy. Gastroenterology 1994; 107: 14751480.
  • 30
    Martin H, Voss K, Hufnagl P, Wack R, Wassilew G. Morphometric and densitometric investigations of protoplasmic astrocytes and neurons in human hepatic encephalopathy. Exp Pathol 1987; 32: 241250.
  • 31
    Lockwood AH, Finn RD, Campbell JA, Richman TB. Factors that affect the uptake of ammonia by the brain: the blood-brain pH gradient. Brain Res 1980; 181: 259266.
  • 32
    Butterworth RF. Pathogenesis of hepatic encephalopathy: new insights from neuroimaging and molecular studies. J Hepatol 2003; 39: 278285.
  • 33
    Weissenborn K, Kolbe H. The basal ganglia and portal-systemic encephalopathy. Metab Brain Dis 1998; 13: 261272.
  • 34
    Weissenborn K, Heidenreich S, Ennen J, Ruckert N, Hecker H. Attention deficits in minimal hepatic encephalopathy. Metab Brain Dis 2001; 16: 1320.
  • 35
    Jobges EM, Heidemann M, Hecker H, Ennen JC, Weissenborn K. Bradykinesia in minimal hepatic encephalopathy (HE) is due to disturbances in movement initiation. J Hepatol 2003; 38: 273280.
  • 36
    Butterworth RF. Pathophysiology of hepatic encephalopathy: a new look at ammonia. Metab Brain Dis 2002; 17: 221227.
  • 37
    Dejong CH, Kampmann MT, Deutz NE, Soeters PB. Cerebral cortex ammonia and glutamine metabolism during liver insufficiency-induced hyperammonemia in the rat. J Neurochem 1992; 59: 10711079.
  • 38
    Cooper AJ, Plum F. Biochemistry and physiology of brain ammonia. Physiol Rev 1987; 67: 440519.
  • 39
    Lavoie J, Giguere JF, Layrargues GP, Butterworth RF. Amino acid changes in autopsied brain tissue from cirrhotic patients with hepatic encephalopathy. J Neurochem 1987; 49: 692697.