Factors for predicting recurrence after burr hole drainage for chronic subdural hematoma: a retrospective study.

Chronic subdural hematoma (SDH) is a common disease in the neurosurgical field, and hematoma drainage through burr hole trephination has been widely considered the optimal treatment for SDH. Despite numerous investigations aimed at predicting recurrence rates and associated factors, studies have demonstrated inconsistent results. In this study, we aimed to comprehensively determine the predictive factors of chronic SDH recurrence in surgically treated patients. We retrospectively evaluated 578 consecutive patients who underwent single burr hole surgery for chronic SDH at our institute between January 2008 and December 2021. Various clinical and radiological factors in patients with and without recurrence were compared using univariate and multivariate logistic regression analyses. A total of 438 patients (531 hemispheres) were analyzed. Fifty-four (10.17%) of the 531 hemispheres had recurrence of chronic SDH within 6 months. Male sex (adjusted odds ratio (aOR) = 3.48; 95% confidence interval (CI), 1.42-8.49), bilateral hematomas (aOR = 2.14; 95% CI, 1.05-4.35), laminar hematoma type (aOR = 2.87; 95% CI, 1.23-6.71), > 30-cm volume of postoperative residual hematoma (aOR = 2.99; 95% CI, 1.01-8.83), and preoperative blood glucose level of ≥ 150 mg/dL (aOR = 2.11; 95% CI, 1.10-4.05) were identified as independent factors associated with recurrence in multivariate logistic regression analysis. The present study revealed that male patients and those who had bilateral hematomas, laminar hematoma type, a large volume of hematoma after surgery, and a high preoperative blood glucose level had a higher probability of experiencing recurrent chronic SDH. We recommend close monitoring of patients 6 months postoperatively to detect subsequent chronic SDH recurrence.