October 13, 2021 by Peter B. Laird
Brain Aneurysms: Vital Insights Into This Complex, Misunderstood Condition
There is no doubt that a brain aneurysm — a weak spot on an artery that balloons or bulges out and fills with blood — can be life-threatening. A ruptured brain aneurysm can cause bleeding in and around the brain, resulting in brain damage, coma, and even death.
Yet, there is a misconception regarding how common brain aneurysms overall have become, explains Brian Snelling, M.D., chief of cerebrovascular and endovascular neurosurgery and the director of the Stroke Program at Marcus Neuroscience Institute at Boca Raton Regional Hospital.
“Around 1 in 50 people has a brain aneurysm, which is much more common than most people would realize,” said Dr. Snelling. “However, because the majority of brain aneurysms are clinically silent until they rupture, most people are unaware how common they are.”
September is National Brain Aneurysm Awareness Month as part of an ongoing effort to educate the public.
Neurosurgeons and interventional neuroradiologists at Miami Neuroscience Institute and Marcus Neuroscience Institute, both part of Baptist Health, utilize leading-edge procedures to treat unruptured aneurysms usually involving coils, stents or other advanced devices to promote clotting and close off the aneurysm with a very high success rate. The devices are placed via a catheter that snakes through a blood vessel, usually from the groin or from the wrist to the brain.
“Brain aneurysms fall into two categories,” explains Dr. Snelling. “If a brain aneurysm has ruptured, that’s an emergency. Those patients need to have the aneurysm secured quickly because there’s a significant risk of re-bleeding of the aneurysm. But when a patient comes to our clinic and they’ve been diagnosed with a brain aneurysm that has not ruptured, there are more options.”
While not all aneurysms require a repair, all need to be monitored.
“It’s important to know the majority of aneurysms are treated conservatively. There are two types of treatment. There’s brain surgery – neurosurgery – and catheter-based or endovascular treatment,” said Dr. Snelling. “The decision of whether to pursue aneurysm treatment, and, if so, which of those to pursue depends on several factors. This includes the patient’s age, their overall health status, whether they smoke, and if they are likely to be compliant with a follow-up. These are only some of the things that play a role in decision making.”
And then there’s the aneurysm itself, Dr. Snelling adds, and a multitude of other factors come into play. “There’s the size of the aneurysm, the location, whether or not the aneurysm’s growing, whether or not they have other aneurysms, whether or not they have a family history of an aneurysm rupture. Those things all play a role in what ultimately is a complex, nuanced decision.”
But what about brain aneurysm symptoms, other risk factors, and screenings? Here are several more insights from Dr. Snelling.
Unruptured brain aneurysms usually don’t have symptoms. Are there any symptoms you can use to identify an unruptured brain aneurysm?
“Brain aneurysms in the vast majority of cases do not have any symptoms — until they rupture. In a small percentage of cases, aneurysms can exhibit what we call warning symptoms, or symptoms of a warning leak where someone may have some new, severe headaches that occur days to weeks before the aneurysm ruptures. In addition, in certain locations, certain aneurysms can result in double or blurry vision. Those are two of the most common ways that patients who have unruptured brain aneurysm may present with symptoms of an aneurysm that’s growing, or changing, and maybe contributing to symptoms other than it rupturing.
“However, there are plenty of other reasons people could have double vision or headaches. Certainly, we don’t want people thinking every headache or perhaps any time they have double vision, it’s because they are harboring a brain aneurysm.”
Have you recently seen several cases of unruptured brain aneurysms? Can you tell me how you were able to find those cases?
“Treating unruptured brain aneurysms is a part of the practice of most of us who treat brain aneurysms. And those aneurysms are usually found for one of two reasons. Usually, they’re found incidentally, meaning someone goes to a doctor and they get imaging of the brain or of the arteries of the brain. And it shows that they harbor a brain aneurysm. The other way would be perhaps they have one of the symptoms we discussed, such as double vision or new headaches, that would prompt that workup.
“The third reason would be due to aneurysm screening because they have a family history, or have another reason to have a brain aneurysm that puts them at a higher risk than the general population. In the vast majority of cases, they’re found incidentally. This is due to the amount of people that get imaging of the brain and of the blood vessels of the brain for other reasons, and they’re found incidentally.”
Are any of the signs of aneurysm rupture the same signs of a stroke? Could a patient confuse the symptoms?
“What I like to tell people is the word stroke is an umbrella term to talk about blood vessel disorders of the brain. When we think of stroke, we’re usually talking about ischemic stroke, and that’s certainly the most common type of stroke. That’s due to a clot that either goes from the heart or breaks off from a plaque and lodges itself in one of the arteries of the brain. And that usually presents things that educate the public on, like the acronym F.A.S.T (F for face drooping; A for arm weakness; S for speech that is slurred and T for time to call 911).
“A brain aneurysm that ruptures still falls under that umbrella term of stroke, but it’s a very different presentation. These patients usually present with a sudden onset of severe headache. Generally, the worst headache of their life because of a rapid increase in pressure, in and around the brain. They can become comatose very quickly or have a depression in consciousness. They can have nausea and vomiting. In some cases, they can have what we call those localizing signs of focal weakness or numbness of one part of the body.
“But it’s generally that presentation of a sudden onset of severe headache, nausea, vomiting, and a depression of consciousness. So, it’s very different from someone with an ischemic stroke who has no headache, no nausea/vomiting, and has a sudden onset of weakness or numbness localized to one half the body, with or without some speech symptoms. They’re actually quite different.”
Does the Institute offer screenings for those at risk for brain aneurysms? And then if so, at what age should those type of screenings begin?
“Generally, the rule is that if you have two first-degree relatives that either have had an aneurysm rupture, or are known to have a brain aneurysm, then that would be someone who should have a screening study. And what I mean by first-degree relatives are either a mother or father, sister or brother, or son or daughter. It has to be within one degree of the patient themselves. For example, a cousin, an aunt, or a grandchild wouldn’t classify as a first-degree relative.
“If you have two first-degree relatives, that warrants a screening study, and in most cases that’s when we use a magnetic resonance angiogram. There’s no radiation and no dye. That’s a safe and effective way of doing the screening study. For a pediatric patient who qualifies for a screening study based on family history, we would recommend a screening when they turn 18. I think that’s a reasonable time to begin.”
Other than family history, are there other risk factors:
“There are certainly other risk factors that can increase the likelihood that you would have a brain aneurysm. Outside of family history, we break those down into things that are modifiable and things that are not modifiable. When I say modifiable, I mean things the patient can influence, like high blood pressure, smoking, high cholesterol, and excessive alcohol use. Things that are not modifiable would be increasing age, female gender, ethnicity, and certain other medical conditions, such as Ehlers-Danlos syndrome, Marfan syndrome, autosomal dominant polycystic kidney disease (ADPKD). These will increase the likelihood that you harbor a brain aneurysm.”