OPERATIONS AND REOPERATIONS FOR CHRONIC SUBDURAL HEMATOMAS DURING A 25-YEAR PERIOD IN A WELL-DEFINED POPULATION

In this retrospective study the hospital records of all patients being operated on for chronic subdural haematomas (CSD) at the Neurosurgica l clinic in Lund in the years 1969, 1979, 1989, and 1993 were examined . 218 patients were operated on, 25 of whom had bilateral haematomas. During the 25-year period the incidence of surgically heated CSD rose from 2 to 5.3 per 100 000 inhabitants per year. The mean age (70.5 pea rs) and the relationship males : females (2 : 1) did not significantly change. The clinical condition of the patients on admission steadily improved during the period. The relative proportion of patients with k nown chronic alcoholism decreased over the pears, but the proportion o f patients Suffering from other complicating diseases increased, as di d the proportion of patients treated with anticoagulants. There was no mortality directly related to surgery, but if defined as deaths withi n one month after surgery, the overall mortality rate was 3.2%. 84.2% of the patients improved following the first operation, in a majority of cases back to the premorbid state. The relative frequency of re-ope rations for CSD was 12.3% and did not significantly change during the period. No pre- or peri-operative variable could be identified which c ould predict who of the patients was at higher risk of re-operation. S urprisingly, the data suggest that the less experienced neurosurgeons bad better operative results compared with their older collegues.