Encephalographic Changes following Subarachnoid Haemorrhage

A review of 22 encephalograms on patients after subarachnoid bleeding revealed that in 11 there was hydrocephalus together with arachnoiditic changes within the basal cisterns. These changes were invariably accompanied by characteristic psychic symptoms. The condition was treated by some form of shunt operation and clinical details of these patients are being reported separately elsewhere; but since the improvement was often dramatic the characteristic radiological picture is described here so that it may be recognised at once. It consists of ventricular dilatation accompanied by obstruction of gas in basal cisterns which are also dilated, sometimes to a very considerable degree.