Delayed remote venous epidural hematoma: direct radiographic identification of a superficial cortical venous source and a review of the literature

PURPOSE: Delayed remote epidural hematoma (EDH) is an exceptionally rare complication of non-traumatic neurosurgical procedures. Although venous bleeding related to abrupt intracranial pressure or volume redistribution has been proposed, the bleeding source is usually inferred rather than directly visualized. We report a delayed contralateral remote EDH after supratentorial tumor resection with direct radiographic evidence of a superficial cortical venous source and provide a review of the literature. METHODS: A comprehensive literature search was performed across PubMed/MEDLINE, Scopus, Web of Science, and the Cochrane Library without temporal restriction. Studies were eligible if they reported individual patient-level data on delayed postoperative epidural hematoma located remote from the operative field after a non-traumatic neurosurgical procedure. Reports of traumatic, intraoperative, immediate, operative-site, or contiguous epidural hematomas were excluded. Two reviewers (E.A.U., O.B.) independently screened records, assessed eligibility, and extracted demographic, clinical, radiological, management, and outcome data for descriptive synthesis. The illustrative case was analyzed with emphasis on clinical and radiographic findings, venous anatomy, and hematoma evolution. RESULTS: The structured review identified 14 previously reported patients with delayed remote postoperative EDH; with the present case, 15 patient-level observations were analyzed. Hydrocephalus was documented in 11 patients (73.3%), and CSF diversion or outflow alteration in 8 (53.3%). Altered mental status was the most common presentation at EDH recognition, occurring in 8 patients (53.3%). Surgical evacuation was performed in 14 patients (93.3%) and the present case was the only patient managed entirely without operative evacuation. Overall, 12 patients (80.0%) had favorable outcomes, 3 (20.0%) had residual neurological deficit or functional decline, and no deaths were reported. CONCLUSIONS: Delayed remote EDH after large-volume supratentorial tumor resection may arise from a superficial cortical venous source. Postoperative sequential imaging in high-risk resections, with preoperative hydrocephalus, superficial venous anomaly, or CSF diversion, may identify remote EDH before neurological deterioration. In selected neurologically intact patients with stable or decreasing hematoma volume, conservative management under close neurosurgical surveillance may be a reasonable approach.