[Electrophysiologic diagnosis of 2 psycho-visual syndromes: Balint syndrome and cortical blindness. A propos of a case of Benson progressive posterior atrophy].

Cortical blindness and Balint's syndrome are two pathologies not well-known. It seems therefore interesting to report a typical patient case, suffering from Benson's posterior cortical atrophy, who presented successively both syndromes. The Balint's syndrome, which results from a bilateral parieto-occipital junction brain injury, and combines clinically a specified triad defects: a spatial disorder of attention, a psychic paralysis of gaze and an optic ataxia. The cortical blindness, which is caused by bilateral damage of the occipital lobes (Broadman area 17). Electrophysiologically, the abolition of short-latency components of visual evoked potentials and the presence of long-latency potentials are recorded. Visual strategy and visual evoked potentials are thus the only objective examinations allowing to diagnose and follow up these patient's evolution. In any case, an adequate visual rehabilitation has to be carried out in order to help the patient recovering his autonomy.