RESUMO
<p><b>OBJECTIVE</b>To probe into the incidence, mechanism and clinical characteristics of chronic subdural hematoma (CSDH) evolving from traumatic subdural effusion (TSE).</p><p><b>METHODS</b>The clinical materials of 32 patients with CSDH evolving from TSH were analyzed retrospectively and the correlative literature was reviewed.</p><p><b>RESULTS</b>16.7% of the patients with TSH evolved into CSDH. The time of evolution was 22 - 100 days after head injury. All patients were cured with hematoma drainage.</p><p><b>CONCLUSIONS</b>TSE is one of the origins of CSDH. The clinical characteristics of TSE evolving into CSDH include polarization of patient age, and chronic small effusion. The patients are usually injured deceleratedly and accompanied with mild cerebral damage.</p>