Electrophysiological alterations in hepatic encephalopathy detected by brain mapping.

Analogical electroencephalogram has been used to study electric alterations in the brain during liver encephalopathy. We adopted digital technique brain mapping to study the electric background activity in the brain and to evaluate the diagnostic and prognosis usefulness of this technique compared with the methods routinely used in this disease. We studied 18 patients with liver cirrhosis and varying degrees of liver encephalopathy and 7 healthy control subjects to assess correlation between the severity of encephalopathy and abnormal electric activity in the brain, and to detect the main differences between the brain mapping findings obtained in the two groups. The findings revealed an overall reduction in the rhythm, increased amplitude and anomalous distribution of the waveforms in the cirrhotic patients. Although similar results have already been reported, brain mapping furnished prompt and more easily visualised findings. Moreover, brain mapping facilitated detailed analysis of wave amplitude, frequency and topographic location indicating that this technique is a valid tool in diagnosing brain disorders.