Our experiences with internal communicating hydrocephalus

: The authors report 51 cases of internal communicating hydrocephalus treated by ventriculo-atrial shunt with a medium Holter valve. According to the origin of the hydrocephalus the patients are divided into three groups: 1) one group with normal pressure hydrocephalus; 2) one group with high pressure hydrocephalus associated with tumors of the CNS, and 3) one group of patients presenting a high pressure hydrocephalus after a severe craniocerebral injury. Different tests have been employed; their results are presented and discussed. The post-operative evolution of these groups are analysed and some conclusions are drawn.