This study was designed to identify high platelet reactivity (HPR) who might have in-stent thrombosis in unruptured aneurysm with intracranial stent placement with light transmittance platelet aggregometry (LTA). For HPR patients, higher ischemic stroke rate maybe occurred, and we hypothesis that dose adjustment of aspirin and clopidogrel based on LTA monitoring maybe reduces the rate of ischemic stroke compared to a standard strategy after intracranial stent implantation at early periprocedural period and 1 month follow-up period.

For the patients of unruptured intracranial aneurysms with stent placement, standard antiplatelet therapy (100mg aspirin + 75mg clopidogrel) is considered to be the most effective antiplatelet regimen in reducing ischemic complications. However, despite the use of standard antiplatelet therapy, a number of patients continue to have ischemic events. A hypothesis is that high platelet reactivity (HPR) patients identified by platelet function test have higher ratio of the ischemic events, and dose adjustment of HPR patients reduces the rate of the ischemic complications at early periprocedural period and follow-up period.

Objectives: The study aim to evaluated the superiority of the strategy of platelet function test(Monitoring Arm) with the modified strategy in HPR patients compared to the standard strategy (Conventional Arm) whether reduce the primary endpoint after intracranial stent implantation at early periprocedural period (7 days) and 1 months follow-up period.

Inclusion Criteria:

1. Age 18 - 80, male or non-pregnant female;
2. patients have unruptured aneurysm who plan to undergo intracranial stent placement;
3. patients with less than 2 of modified Rankin scale score at the day of enrollment;
4. patients who is able to understand the objective of the trial, agrees and signs the written informed consent form.

Exclusion Criteria:

1. The complications related to operation or material quality, such as guidewire pierces out blood vessel, coil herniation, incompletely opened stent, etc;
2. Simultaneous treatment of other cerebrovascular diseases, such as intracranial arteriovenous malformation, Intracranial arteriovenous fistula, etc;
3. Patient with history of hypersensitivity of aspirin, clopidogrel, or ticagrelor;
4. Patients with preoperative prophylactic use of tirofiban;
5. Patients with a high possibility of active bleeding, such as symptomatic intracranial hemorrhage or active gastric ulcer; or patients with coagulopathy;
6. Patients with thrombocytopenia (platelet count <100,000/mm3 within three months before enrollment);
7. patient using anticoagulant;
8. Pregnant or lactating women;
9. Patients with malignant diseases, such as liver disease, kidney disease, congestive heart failure, malignant tumors, etc;
10. Poor compliance patients.