Surgical Treatment of Chronic Subdural Hematoma: Systematic Review and Meta-Analysis of the Literature

Abstract

Background There are many controversies in the literature on the treatment of chronic subdural hematoma (CSDH). Objective To assess the effects of different surgical techniques and postoperative care on recurrence of CSDH. Methods Systematic review through Medline search of articles published between January 1990 and July 2011. Controlled observational and randomized clinical trials (RCT) regarding surgical approach, irrigation, drainage, and postoperative patient position in patients with CSDH were included. The outcome was recurrence requiring reoperation. Independent extraction of articles was conducted by 2 authors using predefined data fields, including study risk of bias indicators. Results 35 publications met inclusion criteria. Pooled analyses did not demonstrate difference in recurrence rates when compared burr-hole craniostomy (BHC) x twist-drill craniostomy (TDC) (OR: 0.99; CI95%: 0.53-1.84; p = 0.97), BHC x craniotomy (OR: 1.23; CI95%: 0.78-1.95; p = 0.36), nor TDC x craniotomy (OR: 16.11; CI95%: 0.85-306.88; p = 0.06). In patients receiving BHC, pooled analysis showed a lower recurrence rate in patients receiving 2BHC compared with 1BHC (OR: 0.58; CI95%: 0.37-0.88; p = 0.01). The use of drainage system after evacuation of CSDH by BHC reduces the recurrence (OR: 0.41; CI95%: 0.23-0.74; p = 0.003).There is not enough evidence to support either a specific location of the tip of drain, nor the postoperative patient position as factors influencing on recurrence. Conclusion Well-designed studies are urgently needed to verify the effectiveness of most neurosurgical procedures routinely performed for CSDH.