Neurologic Deficits and Recovery in Chronic Subdural Hematoma

Chronic subdural hematoma (cSDH) is one of the most common problems treated by neurosurgeons, particularly as the population ages. While often dismissed as a benign problem, it has become clear that cSDH is associated with worse long term functional and cognitive outcomes compared to matched controls. Though surgical techniques for treatment of cSDH are becoming more effective and safe, a persisting problem of fluctuating, stroke-like neurological deficits has re-emerged. Such deficits are not always directly related to hematoma mass effect and not always relieved with surgical decompression, but can result in prolonged hospital course, additional workup, and sometimes even additional invasive treatments. While the cause of such events is unknown, we recently documented for the first time that massive waves of spreading depolarization can occur in these patients and were closely linked to such neurologic deficits in some patients. In the current study, we plan to expand on these preliminary findings with rigorous, standardized application of post operative subdural electrocorticography monitoring, pioneered at our institution to detect SD. We also plan to build on our large retrospective analysis estimating the overall incidence of such deficits in cSDH patients by assessing multiple proposed risk factors for SD. In addition, for the first time, we will assess the short- and long-term consequences of cSDH and SD with detailed functional, cognitive, and headache related outcome measurement. These assessments are based on several remarkable cases we have observed with time-locked neurologic deterioration associated with recurrent SD. This study qualifies as a mechanistic clinical trial in that we will be prospectively assigning patients to the intervention of SD monitoring and assessing outcomes related to the occurrence of SD. This constitutes the application of a novel measure of brain signaling and assessing biomarkers of these physiologic processes of SD. These studies will provide critically needed information on this novel mechanism for neurologic deficits and worse outcomes after cSDH evacuation. Upon successful completion, we would identify a targetable mechanism for poor outcomes that occur commonly in patients with cSDH. This overall strategy offers the opportunity to radically improve the care of patients with cSDH by focusing on clinical trials of pharmacologic therapies for neurologic deficits in patients with cSDH.