Neuroendovascular Surgery (NES) for Cerebral Aneurysms

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Ruptured Aneurysm Causing Subarachnoid Hemorrhage

Ruptured Basilar Apex Aneurysm

Neuroendovascular surgery (NES) is an innovative, minimally-invasive surgical treatment for complex brain and spinal cord vascular diseases that is performed from inside the blood vessels.


Our neuroendovascular surgery team provides treatment for cerebral aneurysm.


What is a cerebral aneurysm?


Cerebral (brain) aneurysms are outward bulges in the blood vessel (artery) in the brain. The bulge is a weakened part of the blood vessel wall.


Aneurysms cause problems in different ways:

  • If the weak spot ruptures, blood will spill out into the space around the brain (the subarachnoid space) and cause a stroke
  • The bulge can get large enough to push on important brain structures to cause problems (like pushing on the nerves to the eyes causing vision problems)
  • Larger aneurysms can form a blood clot, which can break off and flow downstream in a blood vessel and cause either a mini-stroke or a stroke.

How do aneurysms develop?


It is still not completely clear why cerebral aneurysms develop. They are very uncommon in people younger than 20 years of age but are more common with age.

  • Approximately 5 percent of people in the U.S. have or will develop one or more brain aneurysms. Some reports suggest a higher prevalence - as much as 10 percent.
  • Women are more likely to develop an aneurysm than men.
  • Risk factors include hypertension (high blood pressure), smoking and a family history of brain aneurysms (one or more first-degree relatives such as a mother or sibling). People suffering from or having fibromuscular dysplasia or a first-degree relative with an inherited connective tissue disorder such as polycystic kidney disease, alpha-1 anti-trypsin deficiency, Marfan's syndrome and Ehlers-Danlos syndrome, or with neurofibromatosis Type 1, are at higher risk of forming brain aneurysms. The risk of bleeding from an aneurysm ranges from 0.2 to 3 percent per year.

What dangers do cerebral aneurysms present?


If aneurysms break open, the bleeding around and in the brain tissue can cause a stroke and sometimes death. Approximately 30,000 people nationwide suffer an aneurysm-caused hemorrhage each year and approximately half die within the first 30 days. Of those who survive about half suffer permanent deficit. Aneurysms have a great chance of bleeding again, if they are not treated.


Other problems include:

  • Hydrocephalus: Fluid builds in the brain, causing pressure. The fluid can be a small amount or a larger amount that requires a drain be placed.
  • Vasospasm: A narrowing of the blood vessel which reduces the amount of blood reaching the brain tissue and can cause a stroke. Vasospasm is treated both my medication and occasionally by a neuroendovascular procedure during which medication is injected into the brain blood vessels or a balloon is used to relax the blood vessel wall.


What is a cerebral angiogram?


A cerebral angiogram is an X-ray imaging study performed either by a radiologist or a neuroendovascular surgeon to take pictures of the blood vessels going to and in the brain. A catheter is introduced into an artery and carefully guided to the blood vessels in the neck that supply the brain. A liquid containing water and iodine salts (contrast) is injected through the catheter. X-rays show which vessels are normal and create a map of the blood vessels for future treatment. Special types of angiographic images can make a three-dimensional model of the aneurysm.


Cerebral Aneurysm Treatment


Treatment of cerebral aneurysms depends on which blood vessel the aneurysm grows from and the size and shape of the aneurysm. Other key factors include family and personal history and whether you have a connective tissue disease. The goal is to close off the aneurysm so it cannot bleed or rebleed and cause a stroke.


There are two main treatments for cerebral aneurysms

  • Craniotomy (open direct neurosurgery): This approach has been performed for many years and is highly effective and relatively safe. It has the lowest incidence of aneurysm regrowth, if the aneurysm is completely treated. The neurosurgeon creates an opening in the skull and affixes a small, metal clip on the area where the weak bulge joins the normal blood vessel. The clip is permanently left behind.
  • Embolization: During embolization, a catheter or microcatheter is guided from a blood vessel in the groin into the aneurysm. Small, platinum coils are used to fill the aneurysm and block any blood from entering the weak spot. The surgeon may opt to use a soft balloon to help place the coils and a stent to rebuild the vessel wall at the bulge, if the weak spot is very wide. At the end of the treatment only the coils and the stent, if it is used, are left behind. A Pipeline Embolization Device - a stent-like device placed to cover the aneurysm - is a newer technology and usually is not used with coils unless the aneurysm is very large.