Abstract: Objective: To explore the correlation between abnormal CT perfusion( CTP) in the early period of cerebral infarction in patients with transient ischemic attack( TIA) and angiostenosis,and analyse the change of permeability surface( PS). Methods: The CTP and CT angiography( CTA) in 56 patients with TIA were implemented using 128 layers spiral CT machine when cerebral hemorrhage and acute cerebral infarction were ruled out by CT and MRI scanning. The patients with abnormal CT P were divided into stage Ⅰand Ⅱ according to perfusion stage,and mild and moderately severe angiostenosis group according to CTA. Results: Amony 56 patients with abnormal cerebral perfusion,stage Ⅰ in 39 cases and stage Ⅱ in 11 cases were found. According to CTA,mild angiostenosis in 11 cases and moderately severe angiostenosis in 26 cases were found. The difference of perfusion stage between mild and moderately severe angiostenosis group was statistically significant( P 0. 01). The value of PS in lesion side was longer than that in contralateral side in patients with stage Ⅰand Ⅱ( P 0. 01),there was not significant difference between lesions and contralateral side of brain PS in patients with stage Ⅰand Ⅱ( P 0. 05). Conclusions: Abnormal cerebral perfusion in patients with TIA is related with the degree of angiostenosis. The patient prognosis can be evaluated by CTP,CTA combined with clinical sign,which can guide the preventive treatmen.