gms | German Medical Science

Objective: Chronic subdural hematomas (CSDH), a common condition in the elderly, present a therapeutic challenge. Despite general agreement about the indication for operation, the optimal technique and extent of surgery is still controversial. We conducted a volumetric analysis to assess the efficacy of three commonly used surgical methods.

Method: We retrospectively reviewed radiographic and clinical data of 230 CSDHs in 197 consecutive patients, who underwent evacuation of the hematoma through a single burr hole, two burr holes or a mini-craniotomy. Volumetric- and image-based analysis (iPlan, BrainLab, Germany) was used to measure the preoperative volume of the CSDH and the postoperative residual hematoma as well as the trapped air volume, as seen on CT scans 24-72 h after surgery. The mean hematoma density measured in Hounsfield units was also calculated. Analysis of covariance and ordinal regression analysis was used for statistical analysis.

Results: All three methods were equally effective (expressed as percentage drained) in draining a symptomatic CSDH (72 vs 73,4 vs 74,1%, p>.05) irrespective of the radiographic density of the hematoma. There was also no difference in postoperative air volume captured in the subdural space (p>.05). There was also no difference in recurrence rates between the three methods, while patients, who were treated with one or two burr holes were more likely to have a better Glasgow Outcome Score (GOS) than patients treated with a mini-craniotomy.

Conclusions: All three methods are equally effective in draining a CSDH, while less invasive procedures – such as the one – or two burr hole techniques- have a better clinical outcome.