Extracranial-intracranial bypass as hemodynamic rescue for inflammatory intracranial stenosis: A case series and literature review.

Introduction: Inflammatory intracranial stenosis is an uncommon cause of cerebral ischemia. Although medical therapy remains the first-line treatment, some patients continue to experience recurrent symptoms driven by hemodynamic failure. In this setting, the role of extracranial-intracranial bypass remains poorly defined. Research question: Can extracranial-intracranial bypass serve as an adjunctive hemodynamic rescue strategy in selected patients with refractory inflammatory intracranial stenosis? Material and methods: We retrospectively reviewed three patients who underwent surgical revascularization for inflammatory intracranial stenosis and performed a focused literature review of reported bypass cases for vasculitis-related intracranial steno-occlusive disease. Clinical presentation, imaging findings, perfusion assessment, operative strategy, graft patency, and outcomes were analyzed descriptively. Results: All patients had recurrent ischemic symptoms with progressive intracranial steno-occlusive disease and/or impaired cerebrovascular reserve. No bypass required direct anastomosis to a donor or recipient vessel known to show evidence of active inflammation. No intraoperative complications, early postoperative ischemic events, wound complications, or early graft failures occurred. During follow-up, subsequent ischemic events, when present, involved territories remote from the bypass-dependent cortex. Discussion and conclusion: Extracranial-intracranial bypass does not treat the inflammatory disease itself but may provide targeted hemodynamic support in highly selected patients with refractory ischemic symptoms and impaired cerebrovascular reserve. The present experience is exploratory, and further collaborative reporting is needed to clarify indications, timing, and durability.