Idiopathic communicating hydrocephalus: the prognostic significane of ventricular size after shunting.

A description is given of the dramatic, sustained recovery of 3 demented and neurologically disable patients with idiopathic communicating hydrocephalus after they underwent ventriculo-atrial shunting. In those patients there was no significant change in ventricular size after the ventriculo-atrial shunting. 1 of the patients also had cortical atrophy. Hypertensive vasculopathy and multiple infarcts may be the explanation in 2 of the patients. Reveiw of the literature results in the following conclusions: 1) the CAT scan alone, perhaps combined with intrathecal "Amipaque' cisternography, provides the maximum information with the last trauma and may assist in the selection of patients for shunting. 2) Test removal of 20 to 30ml of CSF may be as satisfactory as pressure monitoring and infusion techniques in the prediction of successful shunting. The following do not have a reliable predictive value: a) The presence of cortical atrophy (shunting may sometimes be effective in mild to moderate cortical atrophy) b) The period of onset of symptoms c) The ventricular size before shunting and its alteration after shunting.