Low clopidogrel response has been reported in about 5-44% of the total population, which is associated with an increase in thromboembolism.

Recently prasugrel drug widely accepted as a good option for these patients. The purpose of this study is to compare the safety and usefulness of prasugrel versus clopidogrel in patients who are scheduled to undergo stent or diverter treatment for non-ruptured cerebral aneurysms.

Unruptured intracranial aneurysm (UIA) is a relatively common disease with a prevalence of about 1% of the total population. Widely accepted techniques of neuro-interventional therapy are coil embolization with or without stent deployment and flow diverter insertion. However, these two techniques inevitably had the risk of thromboembolism. For prevention and decrease, dual antiplatelet therapy is commonly used in the clinical field. However, clopidogrel does not produce normal metabolites due to various internal and external factors in the metabolic process in the liver and eventually fails to perform its original role of platelet activity suppression in many situations, called "clopidogrel hyporesponsive". Low clopidogrel response has been reported in about 5-44% of the total population, which is associated with an increase in thromboembolism.

Recently prasugrel drug widely accepted as a good option for these patients. The purpose of this study is to compare the safety and usefulness of prasugrel versus clopidogrel in patients who are scheduled to undergo stent or diverter treatment for non-ruptured cerebral aneurysms.

Inclusion Criteria:

• UIAs without any evidence of rupture in intracranial imaging study within the last 6 months
• Planned treatment with coil embolization with stent insertion or flow diverter insertion
• If the patient himself/herself consented to this study

Exclusion Criteria:

• ∙ History of acute ischemic stroke or transient ischemic attack

  • Any intracranial hemorrhage except subarachnoid hemorrhage due to aneurysm rupture within the last 3 months
  • Concurrent treatment other than endovascular procedure (e.g. open craniotomy and microsurgical clipping)
  • Contraindications to iodine contrast agents
  • Already taking antiplatelet drugs or antithrombotic drugs other than aspirin
  • Hypersensitivity to aspirin, prasugrel or clopidogrel
  • Cardiac arrhythmia that should be needed to take anticoagulants
  • Pregnancy or lactating
  • Chronic kidney disease (< GFR 60)
  • Patients with chronic liver disease who have at least over 100 IU/L of either AST/ALT in the liver function test
  • Patients with pathological active bleeding, such as peptic ulcer
  • Patients with genetic problems, such as galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption because they contain lactose
  • Patients continuously taking non-steroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase-2 inhibitors
  • Patients requiring concomitant administration of methotrexate 15 mg or more for one week
  • If it is judged difficult to follow up after treatment