[Dysconnection syndrome in a boy with tumorous lesion of corpus callosum].

We report on a 12-years-old boy with glioma of the septum pellucidum which invaded and infiltrated the adjacent structures including neocortical commissures. Neuropsychological evaluation revealed the loss of interhemispheric integration and hemisphere dysconnection syndrome. Our patient demonstrated left-sided ideo-motor apraxia to verbal commands and left-sided agrafia, being unable to copy, write to dictation and formulate his own sentences with the left hand. He partly failed in attempts to name or describe objects out of sight in the left hand and showing an unilateral tactile anomia. The patient performed the block-design-test better with the left hand than the right hand, and demonstrated a right-sided constructive apraxia. He had extinction of his left ear on dichotic listening, despite a normal audiogram in both ears. Because of progressive defects of visual function, a tachistoscoping testing was not performed. There was no evidence of the alien hand syndrome, reported earlier. The general dysconnection syndrome caused by lesion of the corpus callosum, was associated with cognitive dysfunctions. Attention, memory and speech disorders were attributed to the progressive extra-callosal cerebral neoplastic lesion. The neurosurgical treatment was performed by transcallosal anterior approach. On neuropsychological retesting, 4 months later symptoms of hemisphere dysconnection were stabilized.