Chronic bilateral sub-dural 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 out come of bilateral chronic subdural hematomas consecutively managed from 199 0 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 p atients (17.4 %). A good outcome was obtained in 97.5 % of the cases and mo rbidity was 14.6 %. The differences significantly observed between unilater al and bilateral subdural hematomas were duration of the prediagnostic peri od, pneumatoceles and recurrence rates (12%). Recurrences were all observed during the first postoperative month and treated with the same initial sta ndardized procedure. The rate of infection or epileptic seizures was low. Conclusions: There are few Limited differences between uni- and bilateral c hronic subdural hematomas. In the latter, a possible correlation between th e duration of prediagnostic period and an increased rate of recurence could be explained by poorer cerebral reexpansion. The overall prognosis of bila teral hematomas is comparable with that observed in unilateral forms. A sim ple and routinely used burr hole procedure either under local or general an esthesia associated with closed drainage is a safe surgical procedure for e ither bilateral or unilateral forms and can be performed in all the cases i ncluding recurrences. Systematic antiepileptic drugs or antibiotherapy are unnecessary in the medical management of chronic subdural hematomas. One la te delayed postoperative clinical control seems to be sufficient.