Cerebral revascularization: extracranial-intracranial bypass

Area of Science:

• Neurosurgery
• Vascular Surgery
• Cerebrovascular Medicine

Background:

• Extracranial-intracranial (EC-IC) bypass is a key revascularization strategy for complex cerebrovascular conditions.
• Endovascular techniques have evolved, yet EC-IC bypass remains relevant for specific neurosurgical applications.
• Current data suggests limited utility for flow augmentation in cerebral ischemia, but it's crucial for selected athero-occlusive disease and symptomatic moyamoya disease.

Purpose of the Study:

• To highlight the enduring role of EC-IC bypass in managing complex cerebrovascular disease.
• To emphasize its relevance in flow replacement for complex/fusiform aneurysms and flow augmentation for specific ischemic conditions.
• To advocate for an objective, flow-based approach to optimize EC-IC bypass decision-making and outcomes.

Main Methods:

• Review of current clinical data and established indications for EC-IC bypass.
• Discussion of EC-IC bypass applications in aneurysm treatment, cerebral ischemia, and moyamoya disease.
• Proposal of a flow-based methodology for enhancing EC-IC bypass management.

Main Results:

• EC-IC bypass is essential for flow replacement before planned vessel sacrifice in complex and fusiform aneurysms.
• Its role in flow augmentation for cerebral ischemia is currently limited but remains viable for select athero-occlusive disease cases.
• EC-IC bypass is a primary treatment for symptomatic moyamoya disease.

Conclusions:

• EC-IC bypass continues to be a critical revascularization technique for specific cerebrovascular pathologies.
• An objective, flow-based approach can significantly improve patient selection, intraoperative assessment, and postoperative management of EC-IC bypass.
• This methodology enhances the overall efficacy and safety of EC-IC bypass surgery.