Radiological Features and Post-Operative Drainage Amount Independently Predict Recurrence of Chronic Subdural Hematoma after Burr-holeCraniostomy

Background: Chronic subdural hematoma (CSDH) is a common neurologic disease in elderly. It is not always a benign condition because high recurrence rate had been reported. Independent risk factors for CSDH recurrence, especially the surgical and post-operative factors, had not been sufficiently investigated. Methods: We retrospectively collected and analyzed data for 125 CSDH patients treated by burr-hole craniostomy in a regional hospital in Taiwan. Results: Of these CSDH patients, the mean age was 70.2 ± 13.2 years and 96 (76.8%) were males. The CSDH recurrence rate after burr-hole craniostomy was 8.8% in our hospital. The recurrence group had thicker hematoma (24 mm vs. 18.5mm, P=0.024) and more often had laminar type CSDH (27.3% vs. 6.1%, P=0.044) than the non-recurrence group. Multivariate analysis found that thicker hematoma (P=0.033; OR=1.121; 95% CI 1.01-1.25), laminar type CSDH (P=0.010; OR=13.461; 95% CI 1.87-97.14) and larger total post-operative drainage amount (P=0.021; OR=1.002; 95% CI 1.000−1.004) were independently associated with recurrence of CSDH after burr-hole craniostomy. We didn’t find an association between burr hole numbers and recurrence rate. Conclusion: We found thicker hematoma,laminar type CSDH and larger post-operative drainage amounts independently predict recurrence of CSDH after burr-hole craniostomy. The patients with these risk factors may need closer surveillance post-operatively. Further studies are needed for surgical method modification to achieve lower recurrence rate.