Hepatic Encephalopathy: Diagnostic Tests

Obligatory medical device diagnostics.

  • Abdominal ultrasonography (ultrasound examination of the abdominal organs) – for basic diagnosis.
  • Computed psychometry – gold standard; very time consuming compared to flicker frequency.
  • Flicker frequency analysis
    • Very accurate form of diagnosis with high sensitivity
    • There is a correlation between the critical flicker frequency and the severity of hepatic encephalopathy: the human eye can perceive flicker only below a frequency of approximately 39 Hz. In the context of hepatic encephalopathy, the critical flicker frequency (CFF/critical flicker frequency) is decreased.

Optional medical device diagnostics – depending on the results of the history, physical examination and obligatory laboratory parameters – for differential diagnostic clarification.

  • Computed tomography of the skull (cranial CT, cranial CT or cCT) – to exclude apoplexy (stroke) in comatose patients.
  • Encephalogram (EEG; recording of brain electrical activity) [triphasic waves (stages II and III of hepatic encephalopathy) or delta activity (stage IV)]