Nevertheless, only in those patients with chronic hepatic dysfunction, a bilateral magnetic resonance alteration on Globos Pallidus is observed,[35] probably because this type of patients selectively shows higher cerebral membrane permeability. Imbalance between aromatic and branched chain aminoacids (Fischer index), traditionally involved in HE genesis,[36][37][38] can be normalized following a MARS treatment. The effects are noticeable even after 3 hours of treatment and this reduction in the Fisher index is accompanied with an improvement in the HE.[39]