Clinical Application On Evaluate The Effection Of Carotid Artery Stenting By Using Cerebral CT Perfusion Imaging

Research objective:With the rapid development in recent years, Carotid Artery Stenting (CAS) has become the effective treatment for carotid artery stenosis as well as Carotid Endarterectomy(CEA), so the safety assessment received widespread attention. This clinical study is to evaluate the cerebral blood perfusion before and after CAS by using the whole brain CT perfusion (CTP) for the patients with symptomatic atherosclerotic carotid artery stenosis.So we can analysis the effection of CAS, and prevent complications such as hyperperfusion syndrome (HS)Method:During Jul.2013 to Jun.2014, Twenty-six Symptomatic Patients with unilateral moderate or severe internal carotid artery atherosclerotic stenosis (defined by the North American Symptomatic Carotid Endarterectomy Trial criteria) (≥50% stenosis on one side and ≤20% stenosis on the other side in all patients, without the other intracranial vascular lesions, or other intracranial diseases), which was confirmed by DSA or CTA, were divided into two groups:TIA group (n=15) and CI (Cerebral Infarction) group (n=11).For all into the group of patients were given the carotid artery stenting (CAS),a total of 26 stents were implanted. All patients were taken the Whole brain CT Perfusion (CTP) 3 days before CAS and 3 days after stenting by GE 64 rows of 128 slice spiral CT. The cerebral perfusion data before and after CAS including relative cerebral blood flow (rCBF), relative cerebral blood volume(rCBV), relative mean transit time(rMTT), and relative time to peak(rTTP) in both groups were compared. The effection of CAS in both groups was compared.Results:1. Comparison among the 2 groups:The numerical changes of rCBF(0.93± 0.01TIA; 0.91±0.02CI), rMTT(1.16±0.08TIA; 1.18±0.05CI), rTTP(1.35±0.15TIA; 1.36±0.13CI) before CAS were statistically significant in 2 groups (P<0.05); rCBV(1.07+0.12TIA; 1.05±0.29CI) numerical difference,2 cases of rCBV were significantly lower,13 cases of mild reduction; 11 cases of mild elevation; The data of rCBF、rMTT、rCBV after CAS in 2 groups were no significant differences, and rTTP was statistical significance changes (P<0.01).2. Comparison before and after CAS in one group:In TIA group, rMTT(1.16 ±0.08Pre; 1.05±0.05Post) and rTTP(1.35±0.15Pre; 1.11±0.05Post) ruduced compared to those before CAS, and rCBF (0.93±0.01Pre; 0.95±0.03Post)increased (P<0.05), and rCBV(1.07±0.12Pre; 1.03±0.06Post) did not change significantly; In CI group, rMTT(1.18±0.05Pre; 1.07±0.06Post) and rTTP(1.36±0.13Pre; 1.12 ±0.06Post) ruduced compared to those before CAS, and rCBF (0.91±0.02Pre; 0.96 ±0.03Post)increased (P<0.05), and rCBV(1.05±0.09Pre; 1.05±0.07Post) did not change significantly, as the same as TIA group.After CAS the rTTP index was still statistical significance changes (P<0.01).Conclusion:The whole brain CT Perfusion is a acceptable and practical technique for the assessment of the hemodynamic modifications in patients with carotid artery stenosis. To evaluate the early ischemia and compensatory capacity of collateral circulation, rTTP is also a sensitive index, which can help to prevent Hyperperfusion Syndrome (HS).So CTP is recommended to be an evaluation tool for high-risk patients with carotid artery stenosis before and after CAS.