Coiling – Brain aneurysm coiling/Balloon-assisted coiling/Stent-assisted coiling

What is coiling? How does it work?

Coiling is a procedure that is performed to block blood flow to a brain aneurysm. A catheter (small tube) is inserted into the affected artery and platinum coils are released into the artery with the help of electrical current. The coils induce clotting inside the artery and seal off the blood flow to the affected area, so your aneurysm will not grow further.

In addition to the typical coiling procedure, there is balloon-assisted coiling and stent-assisted coiling, which might be done if your doctor decides on these procedures based on your condition.

In balloon-assisted coiling, a balloon is temporarily inflated across the affected area, to help guide the coil placement. At the end of the surgery, this balloon is removed and no device will be left inside the artery.

In stent-assisted coiling, a stent in the affected area of the artery allows the coils to remain in the affected area and prevent them from protruding into the main artery and affecting the main blood flow. 

What is expected during the treatment?

Coiling is minimally-invasive, meaning that only a small incision will be made in order to insert the catheter into your artery, and an incision into the skull is not needed, thus there will be no surgical scar. This procedure can be performed as an outpatient procedure, meaning you can return home within the day of the surgery and return to daily activities within the next 48 hours. Thus, this procedure is extremely safe.

You will be under general anesthesia during the procedure and it is usually performed by an interventional neuroradiologist. The surgery will typically take about an hour on average.

The coils released will remain permanently in the aneurysm. They are made of platinum metal and are very small and thin (different sizes can be chosen based on the size of your brain aneurysm). During the surgery, X-ray fluoroscopy will be used to guide the catheter towards the aneurysm.

What conditions does this treatment treat?

The coiling procedure is typically used to treat brain aneurysms. An aneurysm is a bulging artery that occurs where the arterial wall is weak. The enlarged artery inflates in the weak area, and the walls can continue to weaken over time, increasing the risk of a rupture. When a rupture occurs, it could cause a stroke, brain damage or even death in severe cases.

The goal of this treatment is to prevent the rupture of unruptured aneurysms and limiting blood flow to the aneurysm. If the aneurysm has already ruptured, coiling will be performed quickly to prevent the aneurysm from bleeding again.

How will it improve your condition and affect your life? (e.g. change in QOL, change daily tasks, etc.)

After this procedure, you can expect that the aneurysm-related symptoms experienced will resolve within a few weeks. There is a smaller chance of complications such as seizures, compared to other treatments like surgical clipping of aneurysms. In some cases, however, aneurysms can re-grow and you might need to treat them again.

What are some possible side effects or risks?

A risk of this surgery is that the aneurysm might rupture during the surgery, which might lead to a stroke. In some people, the coiling might not be successful and the aneurysm might recur and rupture even after the procedure is done. 

Whenever a catheter is placed into a major blood vessel leading to the brain, there is a small chance that this vessel will get damaged, which could lead to stroke. Usually, the coiling procedure for brain aneurysms is only done when the risk of the aneurysm rupturing is very high. There is also a very small risk of infection from the surgery, as there is with all surgical procedures.

What do I do after I get this treatment?

After the coiling procedure has been completed, you will probably need to return for a couple of check-ups, but minimal follow-up medication will be required and you can more or less resume your daily activities. 

If you have any questions about this procedure, do seek clarification with your doctor and find out whether this treatment is suitable for you.

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