LAUSR

OBJECTIVE The randomized controlled chronic subdural hematoma (cSDH)-Drain-trial showed comparable recurrence rates after placing a subperiosteal drain (SPD) or a subdural drain (SDD) for surgically drained cSDH, while SDD was associated with higher rates of infection and iatrogenic brain injury. This subanalysis examines the time to recurrence and possible risk factors for recurrence after burr-hole drainage of cSDH and placement of a SPD compared to a SDD. METHODS We included 220 patients from the preceding cSDH-Drain-trial. Time to recurrence was compared within the two groups using a univariate cox-proportional hazards model. Apart from intraoperative brain expansion (iBE), defined by residual hematoma-cavity on computer tomography (CT) 24 hours after surgery, other possible pre-, intra- and postoperative risk factors for recurrence were assessed through univariate and multivariate analysis. RESULTS Median time to recurrence was 22.5 days (IQR 9.25 - 52 days, range 0-81) showing no difference between the two groups. Less iBE (p=0.019), lower GOS at discharge (p=0.007) and lower GCS at 24 hours (p=0.037) were strongly associated with recurrence on univariate analysis. After multivariate logistic analysis, less iBE (OR 1.10, CI: 1.01; 1.21; p=0.03) remained the only significant risk factor associated with recurrence. When comparing the risk factors within the two groups, less iBE and lower GOS at release were associated with recurrence, only in the SDD-group. CONCLUSION The inserted drain type after burr-hole drainage of cSDH does not seem to influence time to recurrence. SPD may be warranted in routine clinical practice, independent of individual patient, surgical, or hematoma characteristics.