[Chronic bilateral subdural hematomas].

BACKGROUND AND PURPOSE

Are chronic bilateral subdural hematomas different from unilateral forms in terms of delay of diagnosis, clinical presentation and post-operative recovery or recurrence?

METHODS

Etiological, clinical, and radiological aspects and management outcome of bilateral chronic subdural hematomas consecutively managed from 1990 to 1995 were retrospectively analyzed and compared with unilateral forms managed in the same neurosurgical unit during the same period of time.

RESULTS

There were 236 cases. Bilateral subdural hematomas occurred in 41 patients (17.4%). A good outcome was obtained in 97.5% of the cases and morbidity was 14.6%. The differences significantly observed between unilateral and bilateral subdural hematomas were duration of the prediagnostic period, pneumatoceles and recurrence rates (12%). Recurrences were all observed during the first postoperative month and treated with the same initial standardized procedure. The rate of infection or epileptic seizures was low.

CONCLUSIONS

There are few limited differences between uni- and bilateral chronic subdural hematomas. In the latter, a possible correlation between the duration of prediagnostic period and an increased rate of recurrence could be explained by poorer cerebral reexpansion. The overall prognosis of bilateral hematomas is comparable with that observed in unilateral forms. A simple and routinely used burr hole procedure either under local or general anesthesia associated with closed drainage is a safe surgical procedure for either bilateral or unilateral forms and can be performed in all the cases including recurrences. Systematic antiepileptic drugs or antibiotherapy are unnecessary in the medical management of chronic subdural hematomas. One late delayed postoperative clinical control seems to be sufficient.