[Neuropsychological study of mental troubles in normal pressure hydrocephaly and their short term evolution after spinal fluid derivation (author's transl)].

Starting with 8 neuropsychological detailed observations, the author has studied mental deterioration resulting from normal pressure hydrocephaly and the short term evolution of mental troubles after apinal fluid derivation. The presurgical mental troubles are characterized essentially by short term memory troubles, by behavioural troubles relating to the two poles of the frontal syndrome and by distrubances in writing and calculus. The modification of the state of consciousness, the visual constructive troubles, attention and concentration troubles, verbal language troubles and psychomotor retardation are also frequent. Aphasia and alexia are rare. Generally, postsurgical evolution is immediate and global; the troubles of consciousness, mental deterioration and behaviour disorders are parallely reduced. Globaly, three out of four troubles disappear. Memory troubles and difficulties in concentrating, although improving, are still maintained six month after ventricular drainage.