ANEURYSMAL SUBARACHNOID HEMORRHAGE (SAH)

Q1 What is aneurysmal SAH?

Aneurysm is localized, abnormal out pouching of wall of an artery. Wall of aneurysm is weak and it can rupture to cause hemorrhage. Rupture of intracranial aneurysm will cause subarachnoid hemorrhage.

Q2 What are indications for treating aneurysms?

All aneurysms should be treated, otherwise they will rebleed.
Aneurysmal SAH is an emergency. Earlier the treatment, better- as risk of rebleed and death is ~50% in first month.

Q3 How to treat brain aneurysms?

Brain aneurysms can be treated either by surgical clipping or endovascular coiling.

Q4 What are advantages of coiling over clipping?

Advantages of coiling over clipping are

1. In coiling there is no surgery or opening of brain so
• Its less risky
• There are no surgical complications like meningitis
• Hospital stay is less

2. Coiling can be done even when surgery is contraindicated, like in
• High grade SAH
• Vasospasm
• Multiple aneurysms

3. Results
• Durability and long term results are same as clipping
• Rebleed is rare
• Vasospasm can also be treated in same sitting

Q5 How coiling is done?

Step 1: Femoral artery is punctured and sheath is placed in femoral artery. Then through it guiding catheter is placed into neck vessel.

Step 2: Microcatheter is taken through guiding catheter (blue) in the aneurysm and first coil is deployed within aneurysm.

Step 3: Aneurysm is tightly packed with multiple coils, one after another.

Step 4: Finally microcatheter, guiding catheter and sheath are removed.

CASE 1: Distal anterior cerebral artery (DACA) aneurysm

CASE 2: Posterior inferior cerebellar artery (PICA) aneurysm

Q6 When should we use balloon in coiling?

Balloon should be used in all cases of coiling because
1. It prevents prolapse of coil in parent artery and hence thromboembolic complications. Thus, many wide neck aneurysms can be treated with balloon-assisted coiling, without the need to put a stent.

2. Aneurysm has tendency to rupture any time. This can also occur during the procedure when patient is loaded with anticoagulation. If we don’t have balloon in place, patients usually bleeds to death. If balloon is in position across the neck of aneurysm, we can just inflate the balloon and stop bleeding immediately and can complete the coiling. So balloon helps to save life.

3. In coiling to achieve durable and long-term results (like clipping) we need to pack the aneurysm tightly. Without balloon in place, last coils tend to prolapse in parent artery and so we cannot pack aneurysm tightly. With balloon inflated across neck of aneurysm we can tightly pack the aneurysm without any risk of prolapse and hence we can achieve durable and long-term results like clipping.


CASE 1: Anterior communicating (Acom) artery aneurysm

CASE 2: Posterior communicating (Pcom) artery aneurysm

Q7 When should we use stent in coiling?

Some aneurysms have very wide neck and coil mass tend to prolapse in patent artery, even if we use balloon. In such cases stent act as a scaffold and helps to keep coils within aneurysm. So we do stent-assisted coiling in such wide neck aneurysms.

CASE: Anterior choroidal artery aneurysm

Q8 What is flow divertor? What are its indications?

Flow divertor is nothing but a stent with dense mesh. It is used to treat giant and complex aneurysms and blister aneurysms. It redirects the blood flow away from the aneurysm, causing clot formation and occlusion of aneurysm. Also to be noted that it will not redirect flow in perforators, so aneurysm vanishes but perforators remain patent.