Treating Complex Aneurysms: Balloon-Assisted Coiling, Stent-Assisted Coiling and Flow Diversion

We need awareness at every level, not just among medical professionals but in the community, about the FAST acronym — facial drooping, arm weakness, speech disturbance, all occurring suddenly, and time. Any sudden neurological deficit, sudden severe headache, or sudden seizure requires urgent neuroimaging and immediate transfer to a centre with neuro care capability. A CT or MRI is mandatory, because you cannot distinguish an ischemic stroke from a haemorrhagic one clinically — the imaging is what tells you whether neurointervention is needed.

There are two distinct subsets. In the acute subset, the stroke is actively evolving and intervention has to happen locally — the thrombolytic drug window is 4.5 hours, and mechanical thrombectomy is 6 hours in all cases, extending to 24 hours in selected imaging-positive cases. Acute stroke care has to be developed in and around the patient's own locality; it can't depend on a distant specialist centre. The second subset is secondary prevention, where the stroke has already happened, the cause has been identified, and we're addressing it to prevent a future event. Those are the patients who can make a calculated decision to travel — most of our overseas patients fall into this category.

In haemorrhagic stroke, neurons aren't 100% dead — there's cytotoxic oedema, but if we can remove the blood and relieve the pressure on the brain, neurons can recover function. Our primary goal is to save the patient's life first; the first week to ten days after the bleed is life-threatening, so all effort goes into preventing death and disability, and neurological recovery happens over time through rehabilitation. That's different from ischemic stroke, where we're reversing the deficit on the table itself — rescuing neurons at the brink of death and restoring function immediately.

Not all intracranial haemorrhages require surgical evacuation — most are managed medically. When the bleed is causing raised intracranial pressure, because the brain is inside a closed skull and any extra volume risks herniation, we have to evacuate it. There are several techniques — minimally invasive surgery, stereotactic drainage, or open decompressive surgery — and that's the neurosurgeon's domain. Our endovascular role is in identifying and occluding the underlying vascular cause, the aneurysm or AVM, that caused the bleed in the first place.

Think of it like a blocked drainage system under a city. A surgeon's approach is to dig down from outside to reach the blockage. Our approach is to enter the drainage system from where it begins and navigate a map through the system to the blockage, clearing it from within — you don't have to dig the ground. Access is through a needle puncture in the groin or wrist, and from there the catheters track through the blood vessels all the way to the brain.

When an aneurysm has a wide neck, coils can protrude into the parent artery instead of staying within the aneurysm sac, so additional techniques are needed to hold them in place.

Also called the remodelling technique, it uses a balloon inflated across the aneurysm neck during coil deployment to hold the coils in place, then removes the balloon once the coils are secure.

When balloon support alone is insufficient, particularly for very wide necks, a stent is placed in the parent artery first and coils are delivered through the mesh of the stent.

Rather than filling the aneurysm sac, flow diversion devices, sometimes called pipeline-type devices, divert blood flow away from the aneurysm, causing it to thrombose gradually over time. They are used particularly for large or fusiform aneurysms not well suited to coiling.

It is an intrasac device for aneurysm treatment. Dr. Matin's centre was the first in India, and the first in Asia outside the United States, to use it.