Risk-assessment in chronic subdural hematoma evaluated in 148 patients - A score for predicting recurrence

•Simple risk-score assessment for predicting recurrence of subdural hematoma.•We provide a tool simple to use to assess risk in this difficult to treat patient collective.•Preoperative hematoma thickness >30 mm, thrombocytopenia, midline shift >6 mm, hematoma volume >80 mL and overall hematoma density >45 Hounsfield Units (HU), were significantly more frequent in the recurrence group.•Multivariate assessment, preoperative hematoma thickness, postoperative midline shift and hematoma density were independent risk factors and included in the risk assessment tool.•Tool allows to classify patients in low-, intermediate- and high-risk patients. Chronic subdural hematoma (CSDH) is a frequent disease in neurosurgical practice. However, a considerable recurrence rate keeps this condition challenging to treat. We aimed to provide a simple tool for risk assessment in these patients. We conducted a retrospective analysis of surgically treated patients with chronic subdural hematomas. In addition to patients’ demographics, radiological assessment included volume, thickness, midline shift and density of hematomas. Statistically significant variables in univariate analysis were further analyzed in a multivariate logistic regression model to create a risk score for recurrence of CSDH. A total of 148 patients were identified and included for analysis. 50.7 % (n = 75) were older than 76 years of age. The overall hematoma recurrence rate requiring surgery was 23.6 % (n = 35). Preoperative thrombocytopenia, postoperative midline shift >6 mm, hematoma volume >80 mL and overall hematoma density >45 Hounsfield Units (HU), were significantly more frequent in the recurrence group. Furthermore, after multivariate assessment, postoperative hematoma density and volume were independent risk factors and included in the risk assessment tool. Patients were divided into 3 risk groups corresponding to the total scores. We provide a risk-score assessment for predicting recurrence of subdural hematoma. The risk-score comprises postoperative hematoma volume and density. This tool could ease decision making in follow-up evaluation and indication for recurrence surgery. Yet, further prospective evaluation is required to assess the clinical value of this tool.