[Evaluation of brain evoked potentials in the detection of subclinical hepatic encephalopathy in cirrhotics]. 
Brainstem auditory evoked potentials (BAEP), visual evoked potentials (VEP) and short latency somatosensory evoked potentials (SSEP) were examined in 30 nonalcoholic liver cirrhotics without clinically detectable hepatic encephalopathy and 30 healthy controls.  In the cirrhotics, all peak latencies of the three kinds of evoked potentials, the interpeak latencies (IPLs) I-V, III-V of BAEP and the IPLs N13-N20, N13-P25 of SSEP were significantly prolonged compared with the controls, respectively.  The amplitudes of P100, N125 of VEP were significantly lowered in the cirrhotics than those of the controls.  Abnormal BAEP test and abnormal SSEP test results were found in both 60% of the cirrhotics, while VEP tests showed abnormalities in only 36.7%.  In total, abnormal evoked potential test of one or more kinds were found in 90% of the cirrhotics.  It is concluded that in cirrhotic patients, before the appearance of clinically encephalopathy, there were already brain evoked potential abnormalities or brain function changes.  Our results argue in favor of the three kinds of evoked potential as the combined investigation for the sensitive and objective diagnosis of subclinical hepatic encephalopathy in patients with nonalcoholic cirrhosis.