Overview
A flow diverter is a type of endovascular device used in the treatment of cerebral aneurysms. It is designed to redirect blood flow away from the aneurysm sac, promoting thrombosis and subsequent occlusion. Unlike traditional coil embolization, which fills the aneurysm sac with coils, flow diverters are placed across the neck, altering blood flow dynamics. This innovative approach offers a minimally invasive alternative for treating complex aneurysms, particularly those with wide necks or irregular shapes.

Types of Flow Diverter

• Pipeline Embolization Device (PED): A braided mesh tube to divert blood flow away from the aneurysm and promote thrombosis.
• Silk Flow Diverter: Similar to PED, it is a braided stent-like device that redirects blood flow and induces aneurysm occlusion.
• Surpass Flow Diverter: A self-expanding mesh device that provides a scaffold across the aneurysm neck, promoting endothelial growth and aneurysm exclusion.
• Flow Redirection Endoluminal Device (FRED): A dual-layer stent to divert blood flow while maintaining parent vessel patency.

Why Do You Need A Flow Diverter?
Flow diverters are utilized in the treatment of cerebral aneurysms for several reasons:

• Complex Aneurysm Morphology: Flow diverters are effective for treating wide-necked or irregularly shaped aneurysms, where traditional coiling or clipping techniques may be challenging.
• Aneurysm Rupture Prevention: By redirecting blood flow away from the aneurysm sac, flow diverters promote thrombosis within the aneurysm, reducing the risk of rupture and subsequent hemorrhage.
• Minimally Invasive: Flow diverter placement is a less invasive alternative to open surgical procedures, offering patients shorter recovery times and reduced risk of complications.

How Are Patients Selected For The Procedure? 
Patient selection for flow diverter placement involves a thorough evaluation by a multidisciplinary team of neurosurgeons, interventional neuroradiologists, and neurologists. Factors considered include the size, location, and morphology of the aneurysm and the patient's overall health status and medical history. Imaging studies such as angiograms and CT scans help assess the anatomy of the aneurysm and surrounding blood vessels. Shared decision-making between the medical team and the patient ensures that the benefits and risks of flow diverter placement are carefully weighed before proceeding with the procedure.

Risks And Benefits Associated With The Chosen Flow Diverter
Benefits of Flow Diverter:

• Aneurysm Occlusion: Flow diverters effectively redirect blood flow away from the aneurysm, promoting thrombosis within the sac and eventual aneurysm occlusion.
• Minimally Invasive: Compared to open surgical procedures, flow diverter placement is less invasive, resulting in shorter recovery times and reduced risk of complications.
• Wide-Necked Aneurysms: Flow diverters are particularly effective for treating wide-necked or complex-shaped aneurysms where traditional coiling or clipping techniques may be challenging.

Risks of Flow Diverter:

• Thromboembolism: Flow diverter placement can lead to the formation of blood clots, increasing the risk of stroke or other thromboembolic events.
• Incomplete Occlusion: Flow diverters may fail to occlude the aneurysm, necessitating additional treatment or surveillance completely.
• Perforation: Improper placement or deployment of the flow diverter may result in vessel perforation, requiring immediate intervention to prevent complications.

Recovery And Rehabilitation After The Flow Diverter
Recovery and rehabilitation following flow diverter placement involve a period of observation in the hospital to monitor for any immediate complications. Patients may experience mild discomfort at the access site, which resolves within a few days. Gradual resumption of normal activities is encouraged, with restrictions on strenuous activities. Follow-up appointments are scheduled to assess aneurysm occlusion and overall recovery progress. Long-term management may involve medication to prevent blood clots and regular imaging studies to monitor the effectiveness of the flow diverter in excluding the aneurysm from the circulation and preventing rupture.

What To Expect After A Flow Diverter?
After flow diverter placement, patients can expect a period of observation in the hospital to monitor for any immediate complications. Mild discomfort at the access site is common and usually resolves within days. Gradual return to normal activities is advised, with restrictions on strenuous tasks. Follow-up appointments are scheduled to evaluate aneurysm occlusion and recovery progress. Long-term management may involve medication to prevent blood clots and periodic imaging studies to assess the effectiveness of the flow diverter in excluding the aneurysm from the circulation and reducing the risk of rupture.