Volume and Midline Shift as Preoperative Computed Tomography Imaging Predictors of Postoperative Chronic Subdural Hematoma Recurrence: Retrospective Review of 345 Patients With 412 Operative Subdural Sides

Abstract

Abstract INTRODUCTION The treatment and management of chronic subdural hematoma (cSDH) is highly variable, with recurrent surgery resulting in increased elderly morbidity, and economic burden to patients and the healthcare system. By conducting a retrospective review of patients with cSDH who underwent evacuation, we will provide a better understanding of predictive factors of recurrence, thereby optimizing a surgeon's management and treatment. METHODS We conducted a retrospective review of 345 patients with a total of 412 sides of cSDH, who received either burr-hole craniostomy or a craniotomy with closed system drainage. We reviewed the immediate preoperative and postoperative computed tomography (CT) scan, and defined recurrence as repeat surgical intervention on the side of initial evacuation. We performed a per-patient and per-side analysis of the collected data. RESULTS A total of 49 (11.9%) patients and 51 sides (12.4%) experienced a recurrent cSDH requiring re-evacuation. In the per-patient analysis, the preoperative hematoma volume [CI 1.082 (1.013-1.155)] and midline shift at the third ventricle [CI 1.118 (1.1028-1.215)] were predictors of recurrence. This was also observed in the per-side analysis at CI 1.088 (1.021-1.159) and CI 1.130 (1.045-1.222), respectively. On the per-patient side, comorbidities (diabetes, liver disease, alcohol abuse, antiplatelet/anticoagulant medication) and other demographic factors (gender, age) were not linked to recurrence. If a patient had a bilateral hematoma and both sides were operated on, it was found to be protective of recurrence with a CI of 0.111 (0.025-0.486). CONCLUSION Larger preoperative volumes and a greater midline shift significantly increased the risk of re-evacuation for cSDH, while other demographic and CT characteristics did not. Therefore, this may represent that a high-risk subgroup can be used as a target for preventative therapy.