[Recurrence following burr hole trephination of chronic subdural hematomas].

In a consecutive series of 100 patients suffering from Chronic subdural haematomas, which were treated by burr-hole evacuation and closed external drainage, in 23 patients repeated operations became necessary. The reasons for further operations were: true recurrences in 11 cases, superimposed haematomas in five cases and haematomas on the opposite side in seven cases. All these patients were treated again by burr-hole evacuation and closed external drainage. In contrast to the common opinion craniotomy and removal of the membranes was not necessary in any case.