Application of Extended Reality (XR)-Assisted Computed Tomography (CT)-Guided Localization in Extracranial-intracranial (EC-IC) Bypass Surgery

Inclusion Criteria: * Adult patients diagnosed with ischemic moyamoya disease, moyamoya syndrome, or chronic intracranial internal carotid artery stenosis or occlusion (chronic ICA stenosis/occlusion). * Patients scheduled to undergo extracranial-intracranial bypass surgery (EC-IC bypass), including superficial temporal artery-middle cerebral artery bypass (STA-MCA bypass), superficial temporal artery trunk-interposition graft-middle cerebral artery bypass (STA trunk-graft-MCA bypass), or other cerebral revascularization procedures using the superficial temporal artery or another branch of the external carotid artery system (STA/ECA system) as the donor blood supply. Exclusion Criteria: * Presence of a contraindication to computed tomography (CT) scanning. * Presence of a severe systemic illness that would prevent participation in subsequent study assessments, such as poorly controlled diabetes mellitus, active malignancy, or severe cardiac disease. * The need for emergency surgery without sufficient time to complete image-based modeling and registration. * Presence of scalp lesions, wounds, or anatomical deformities that prevent reliable surface registration. * The XR registration result is considered unreliable by the research team and may potentially compromise surgical safety.