Safety Study of the PulseRider® in Patients Undergoing Treatment for Bifurcation Intracranial Aneurysms

Primary Endpoints:

Safety: Death or stroke in downstream territory to 180-days post-procedure Technical Success: Device placement success and ability to retain coils within the aneurysm (as judged by the treating physician at the time of the procedure. Core lab will review images at a later time) Rate of aneurysm occlusion at Day zero (0) and 180-days

Additional Evaluations to 180-days and at 365-day follow up Rate of aneurysm occlusion at 365 days Device movement or migration defined as any relative change in the position of the device with respect to the parent and/or daughter vessels that is greater than 2mm by conventional catheter angiography, CTA or MRA (180 days) and (365 days) Stenosis defined as >50% at implant site by conventional catheter angiography, MRA or CTA at 180 days and at 365 days Rate of incidence of new neurological deficits Complication rate (neurological and non-neurological)

Inclusion criteria

• Patient who presents with an MRA, CTA or angiographically confirmed, wide neck (> 4 mm or dome to neck ratio < 2) intracranial aneurysms located at a bifurcation
• The target aneurysm is in a vessel with a diameter of 2.7 mm to 4.5mm.
• The patient is 18 years or older at the time of consent
• The patient has signed the IRB/EC approved informed consent form
• In the opinion of the physician, placement of the PulseRider is technically feasible and clinically indicated
• Subject has mental capacity and is willing and able to comply with protocol requirements and follow-up

Exclusion criteria

• Unstable neurological deficit (condition worsening within the last 90 days)
• Subarachnoid Hemorrhage (SAH) within the last 60 days
• Irreversible bleeding disorder
• mRS score ≥3
• Patient has another aneurysm which, in the Investigator's opinion, will require treatment within the follow up period (365 days)
• Platelet count < 100 x 103 cells/mm3or known platelet dysfunction
• Inability to tolerate, adverse reaction or contraindication to taking aspirin or clopidogrel
• A history of contrast allergy that cannot be medically controlled
• Known allergy to nickel
• Relative contraindication to angiography (e.g., serum creatinine > 2.5 mg/dL)
• Woman with child-bearing potential who cannot provide a negative pregnancy test
• Evidence of active infection (fever with temperature > 38°C and/or WBC > 15,000)
• Other conditions of the heart, blood, brain or intracranial vessels that carry a high risk of neurologic events
• Evidence of disease or condition expected to compromise survival or ability to complete follow-up assessments during the 365-day follow-up period
• Extracranial stenosis greater than 50% in the parent artery requiring access to the lesion
• Intracranial stenosis greater than 50% in the treated vessel
• Extreme vessel tortuosity that prohibits appropriate control of the micro-guide wire and/or the PulseRider delivery wire