A brain aneurysm is a weakened, bulging area in an artery wall within the brain that can rupture, causing life-threatening bleeding. To prevent this, surgeons may use a stent, which is a flexible mesh tube, in a minimally invasive procedure. This treatment reinforces the blood vessel and avoids open brain surgery. The goal is to divert blood flow away from the aneurysm, reducing pressure and allowing it to heal over time.
Types of Aneurysm Stenting
One method is flow diversion, which uses a specialized, tightly woven mesh stent placed in the main artery across the aneurysm’s opening. The stent acts as a new lining, redirecting blood flow past the aneurysm instead of into it. This redirection reduces pressure on the weakened vessel wall, making a rupture less likely. This method is effective for larger or complex aneurysms.
Without the constant force of blood flow, the blood inside the aneurysm begins to clot. Over several weeks to months, the body’s healing processes cause the aneurysm to shrink and become sealed off. New cells grow over the stent, integrating it into the vessel wall and permanently repairing the artery.
Another technique is stent-assisted coiling, often used for aneurysms with a wide opening, or “neck,” where coils might not stay in position. A surgeon guides tiny, soft platinum coils through a catheter directly into the aneurysm sac. These coils fill the space, disrupting blood flow and promoting a clot that seals the aneurysm from the inside.
To ensure the coils remain securely packed, a stent is then placed across the aneurysm’s neck in the main artery. The stent acts as a scaffold, preventing the coils from shifting out into the blood vessel. This combined approach ensures the aneurysm is blocked off while the main artery remains open for blood flow.
The Stenting Procedure
Before the procedure, a patient undergoes detailed imaging tests, such as a cerebral angiogram or MRI, to map the aneurysm’s exact location and shape. Patients are also started on blood-thinning medications, like aspirin, to prevent clots from forming during and after the intervention. These preparatory steps ensure the surgical team has a clear plan.
The procedure is performed under general anesthesia. A surgeon makes a small incision, usually in the femoral artery in the groin or an artery in the wrist, to insert a catheter. Guided by real-time X-ray imaging, the surgeon navigates this catheter through the body’s blood vessels to the affected artery in the brain.
Once the catheter is in position, the stent is deployed and placed across the aneurysm’s opening. It expands to fit the artery’s inner wall, either redirecting blood flow on its own or holding coils in place. After the stent is secured, the catheter is withdrawn.
Immediately following the procedure, the patient is moved to a recovery area or an intensive care unit (ICU) for close monitoring. Medical staff observe vital signs and neurological function to ensure there are no immediate complications before the patient is moved to a regular hospital room.
Recovery and Life After Stenting
Initial recovery in the hospital is brief, with most patients staying for one to two days for observation. It is common to experience some fatigue, headaches, or soreness at the catheter insertion site. Doctors recommend avoiding strenuous activities and heavy lifting for at least a week, and most people return to their normal routines within a week or two.
Long-term management requires taking antiplatelet medications, often a combination of aspirin and another drug like clopidogrel, for several months to a lifetime. These blood thinners are necessary to prevent blood clots from forming on the metal stent. Stopping these medications without medical guidance can lead to serious complications, including a stroke.
Consistent follow-up is part of life after a stent placement. Surgeons schedule follow-up imaging tests, such as angiograms or MRAs, at regular intervals to monitor the stent and the aneurysm. These checks, often at six months, one year, and then periodically, confirm the treatment is effective.
Potential Risks and Complications
The procedure carries risks related to the use of a catheter. During navigation to the brain, there is a possibility of damaging the blood vessel. Bleeding or infection can also occur at the incision site. One of the more significant risks is causing a stroke if a blood clot becomes dislodged during the intervention.
Complications specific to the stent can also arise after the procedure. A primary concern is the formation of a blood clot on the stent itself, a condition known as stent thrombosis, which can block blood flow and lead to a stroke. Another potential issue is in-stent stenosis, where tissue grows into the stent, causing the artery to narrow again.
There are also risks related to the aneurysm itself after treatment. In some cases, the aneurysm may not be completely sealed off by the stent or coils, which could require further treatment. There remains a small risk that the aneurysm could bleed despite the presence of the stent.