Clinical Report: Outcomes of Subdural vs Subgaleal Drains in Chronic Subdural Hematoma

Overview

This retrospective study compared clinical outcomes of subdural and subgaleal drain placements following burr-hole drainage in chronic subdural hematoma (CSDH) patients. It found no significant difference in recurrence rates or morbidity between the two drain locations, suggesting both methods are viable options.

Background

Chronic subdural hematoma is a common neurosurgical condition characterized by blood accumulation between the dura and arachnoid mater, with increased incidence in the elderly and those on anticoagulant or antithrombotic therapy. Burr-hole craniostomy with drain placement is the gold standard treatment to reduce recurrence risk. However, the optimal drain location—subdural versus subgaleal—remains controversial due to differing risks and efficacy profiles. This study investigates whether drain location affects clinical outcomes after burr-hole drainage for CSDH.

Data Highlights

The study included adult patients undergoing burr-hole drainage for de novo CSDH between 2017 and 2022 at a single academic center. Baseline characteristics such as age, sex, bleeding risk factors, and anticoagulant use were recorded. Primary outcome was recurrence rate within six months, defined by symptomatic ipsilateral hematoma reaccumulation on CT. Secondary outcomes included morbidity assessed by modified Rankin Scale and postoperative complications within six weeks. Drain placement was pseudo-randomized based on surgeon preference, with either subdural or subgaleal drains used.

Key Findings

• No statistically significant difference in recurrence rates of CSDH was observed between subdural and subgaleal drain groups within six months post-surgery.
• Morbidity, measured by modified Rankin Scale scores at six weeks, was comparable between the two drain placement methods.
• Complication rates, including bleeding, infection, convulsions, and wound issues, did not differ significantly between subdural and subgaleal drain groups.
• Subdural drains carry theoretical risks of brain injury and seizures, but this study did not demonstrate increased adverse events compared to subgaleal drains.
• Practice variation based on surgeon preference did not impact overall patient outcomes, supporting flexibility in drain placement choice.

Clinical Implications

Clinicians can consider either subdural or subgaleal drain placement following burr-hole drainage for CSDH without compromising patient outcomes. The choice may be guided by surgeon experience and patient-specific factors rather than concerns over differential recurrence or complication rates. This flexibility may facilitate individualized surgical planning and resource utilization.

Conclusion

This study supports that both subdural and subgaleal drains are effective and safe for managing chronic subdural hematoma after burr-hole evacuation, with no significant differences in recurrence or morbidity. Further prospective studies could reinforce these findings and guide standardized protocols.

References

1. Utrecht University Medical Center Study 2017-2022 -- Comparative Analysis of Clinical Outcomes for Subdural and Subgaleal Drains Following Burr-Hole Drainage in Chronic Subdural Hematoma Cases