We examined a 41-year-old female with a subacute Budd-Chiari Syndrome (BCS) before and after implantation of a transjugular intrahepatic portosystemic stent shunt (TIPSS) by means of digital electroencephalography (EEG). After TIPSS implantation hepatic decompression had been achieved and the liver function as well as the clinical status improved daily. Simultaneously, the digital EEG showed a decrease in the power of the theta band and an increase in the physiological alpha frequency band. The theta/alpha ratio decreased after TIPSS, despite an elevated arterial ammonia level. The patient had a well-preserved liver parenchyma before the occurrence of the BCS. After portal decompression by TIPSS, the liver function normalized and the liver resumed efficient synthesis and parts of its detoxification task. This regeneration capacity was documented by a rise in cholinesterase after TIPSS. After temporary substitution of albumin the serum albumin concentration returned to normal. Thus, some neurotoxic substances with high albumin-binding capacity may not be absorbed by the central nervous system (CNS). Furthermore, it appears likely that the length of time the brain is exposed to neurotoxic substances plays a role in the clinical and electroencephalographic changes. Compared to the conventional EEG the theta/alpha ratio reflected better metabolically conditioned electroencephalographic changes after TIPSS.