By utilizing Computed Tomography (CT) perfusion technology, we analyzed hemodynamic characteristics before and after intracranial and extracranial vascular anastomosis for ischemic cerebrovascular disease and evaluated therapeutic efficacy. Fifty-seven patients with ischemic cerebrovascular disease underwent intracranial and extracranial vascular anastomoses. CT perfusion was evaluated before and after anastomosis. The preoperative diagnoses included Transient Ischemic Attack (TIA), Reversible Ischemic Neurological Deficit (RIND), and atypical symptoms of cerebral ischemia. Evaluation of middle cerebral artery distribution and cerebral watershed area indicated obvious delay in CT perfusion. Regional cerebral blood flow was slightly reduced or normal, and perfusion in the cerebral watershed area after anastomosis recovered to normal. The area of perfusion delay was obviously reduced after anastomosis. CT perfusion indicated improvement of 84.2%. CT perfusion technology can accurately evaluate the hemodynamic status of unilateral anterior circulation arterial stenosis, and surgical treatment can improve this hemodynamic barrier. The curative effect was objectively and accurately evaluated using CT perfusion technology.