Abstract

Abstract Objective Chronic subdural hematoma (CSDH) is a common neurological condition and is typically treated with burr hole craniostomy. Nevertheless, conservative treatment may lead to spontaneous hematoma resolution in some patients. This study aims to describe the characteristics of patients who were treated conservatively without the eventual need for additional treatment. Methods Data were retrospectively collected from patients who were primarily treated conservatively in three hospitals in the Netherlands from 2008 to 2018. The Primary outcome was the nonnecessity of additional treatment within 3 months after the initial CSDH diagnosis. We used univariable and multivariable logistic regression analyses to identify factors associated with not receiving additional treatment. Results In this study, 83 patients were included and 61 patients (73%) did not receive additional treatment within 3 months. Upon first presentation, the patients had a Markwalder Grading Scale score (MGS) of 0 ( n = 5, 6%), 1 ( n = 43, 52%), and 2 ( n = 35, 42%). Additional treatment was less often received by patients with smaller hematoma volumes (adjusted odds ratio [aOR] 0.78 per 10 mL; 95% confidence interval [CI] 0.64–0.92). Patients using antithrombotic medication also received less additional treatment, but this association was not significant (aOR 2.02; 95% CI 0.61–6.69). Conclusions Three quarters of the initially conservatively treated CSDH patients do not receive additional management. Typically, these patients have smaller hematoma volumes. Further, prospective research is needed to distinguish which patients require surgical intervention and in whom primary conservative treatment suffices.