Table 2

Grading of electroencephalographic changes in hepatic encephalopathy

AGeneralised suppression of alpha rhythm
BUnstable alpha rhythm with paroxysmal waves at 5 to 7 per second; occasional underlying fast activity
CRuns of medium voltage 5 to 6 per second waves bilaterally over frontal and temporal lobes; alpha rhythm seen occasionally
DConstant 5 to 6 per second waves in all areas
EBilaterally synchronous, 2 to 3 per second waves, predominating over frontal lobes and spreading backward to occipital lobes; occasional short-lived appearance of faster rhythms (5 to 6 per second)
  • From Parsons-Smith et al. 22