Risk factors associated with recurrence after burr-hole evacuation for chronic subdural hematoma

Abstract

Chronic subdural hematoma is one of the most common diseases encountered in neurosurgical practice. Although the treatment method is well established, the factors associated with recurrence are not understood.To identify the risk factors for recurrence, we compared the clinical features of two groups of patients: patients with recurrence (recurrence) and those without recurrence (non-recurrence).The study included 662 adult patients (769 operation cases) who had undergone a burr-hole surgery between January 2000 and December 2010. The recurrence factors were retrospectively analyzed, and the primary endpoint was defined as the time at which recurrence warranted re- drainage.The recurrence factors were age (more than 70 years),days from trauma to operation (more than 70 days), bilateral hematoma, bilateral operation, density on preoperative computed tomography scans (niveau), volume of preoperative hematoma (more than 80 ml),and hematoma cavity reduction ratio.We concluded that the re-expansion of the brain postoperatively was the factor that was most closely associated with recurrence. Our results indicate that neurosurgeons may need to wash out hematomas and prevent air invasion of the subdural space during operation to reduce the possibility of recurrence.