Bradykinesia in cirrhotic patients with early hepatic encephalopathy is related to a decreased glucose uptake of frontomesial cortical areas relevant for movement initiation.

BACKGROUND/AIMS: Bradykinesia is one of the first symptoms of hepatic encephalopathy (HE). Recently it has been suggested that bradykinesia in HE is due to disturbances in movement initiation. Areas involved in self-initiated movement are the motor- and premotor cortex, the supplementary motor cortex, the motor areas of the cingulate gyrus, and part of the frontomesial- and parietal cortex. The present study aimed to test the hypothesis that bradykinesia in HE is due to a functional disturbance of these areas. METHODS: Fourteen cirrhotics with grade 0-I HE were examined. Patients with alcoholic cirrhosis or concomitant cerebral disorder were excluded. Patients underwent a 3-dimensional computer-assisted movement analysis for forearm pronation and supination, hand tapping and finger tapping and a (18)F-fluorodesoxy-glucose-PET-examination during rest, analysed with statistical parametric mapping (SPM99). RESULTS: The frequency of finger- and hand tapping was significantly correlated to the glucose metabolism of the motor area of the cingulate gyrus and frontomedial, frontodorsal and parietal cortical areas known to be activated with self-initiated movements. A decrease of movement frequency was associated with a reduction of glucose metabolism within these areas. CONCLUSIONS: These data support the hypothesis that bradykinesia in cirrhotics with HE is caused by an alteration of movement initiation.

Hepatitis C virus infection affects the brain-evidence from psychometric studies and magnetic resonance spectroscopy.

BACKGROUND/AIMS: Up to 50% of patients infected with the hepatitis C virus (HCV) complain of chronic fatigue and difficulties in concentration and memory. The aim of the present study was to seek evidence for the presence of central nervous system involvement in HCV infected patients with only mild liver disease. METHODS: Thirty HCV infected patients with normal liver function, 15 of whom were identified as having mild and 15 moderate to severe fatigue using the fatigue impact scale, underwent neurological and neuropsychological examination, electroencephalography (EEG) and cerebral proton magnetic resonance imaging (MRI) and spectroscopy (MRS). Fifteen healthy volunteers, matched for age and educational attainment, served as controls. RESULTS: In comparison to the healthy controls the patients with HCV infection showed evidence of cognitive impairment, primarily attention and higher executive functions, higher levels of anxiety and depression and impairment of quality of life. In addition they showed a significant decrease of the N-acetyl-aspartate/creatine ratio in the cerebral cortex on 1H MRS while the EEG was slowed in 25%. In general the deficits were more marked in the patients with moderate rather than mild fatigue. CONCLUSIONS: The data provide evidence of central nervous system involvement in patients with HCV infection.

Bradykinesia in minimal hepatic encephalopathy is due to disturbances in movement initiation.

BACKGROUND: One of the predominant symptoms of early stages of hepatic encephalopathy (HE) is bradykinesia. AIMS: To further analyze the pathophysiology of bradykinesia in HE. METHODS: A three-dimensional computer-assisted movement analysis was performed in 36 cirrhotics with grade 0-I HE compared to 18 controls selected with regard to sex and age and 16 patients with Parkinson's disease (PD). Four types of movement were studied: finger tapping, hand tapping, pronation/supination of the forearm and flexion/extension in the hip joint. RESULTS: The patients with PD presented with a decrease of the maximal movement velocity (VMAX) and a prolongation of the time needed to reach VMAX (VTIME). In patients with minimal or grade I HE, the VMAX of all movements was unchanged compared to controls while the VTIME was significantly prolonged. This was caused by a delay before the beginning of each new part of the diadochokinetic movement cycle. CONCLUSIONS: The data suggest an impairment of movement initiation as main cause of bradykinesia in early HE.