Shots - Health News
Mon December 10, 2012
As Childhood Strokes Increase, Surgeons Aim To Reduce Risks
Originally published on Mon December 10, 2012 2:08 pm
Boston brain surgeon Ed Smith points to a tangle of delicate gray shadows on his computer screen. It's an X-ray of the blood vessels on the left side of 13-year-old Maribel Ramos' brain.
"If we follow this blood vessel up here, you see that right there it gets pinched off almost to nothing," Smith explains, "and then this little puff of smoke right here, which are these little narrow blood vessels that don't fill the rest of the brain as it normally should." Maribel's brain is starved for oxygen, he says.
Those spidery blood vessels represent an effort by the girl's body to compensate for the pinched section of her major cerebral artery. In fact, "puff of smoke" is the actual name of Maribel's disorder — "moyamoya" in Japanese — because the researchers who named it thought that's what it looked like on X-rays.
The disorder is just one of many conditions that can make a child more prone to strokes. One in 10,000 kids will suffer a stroke, causing disability or even death. But surgeons can now prevent strokes in some of these children — children like Maribel.
Moyamoya is not Maribel's only health condition. She also suffers from sickle cell disease, a much more common disorder that causes red blood cells to be spiky and misshapen — and prone to form blood clots in the dangerously narrow blood vessels of her brain. Sickle cell disease is the most common cause of strokes in children.
Smith, who works at Children's Hospital in Boston, says the combination gives Maribel a 95 percent chance of suffering a disabling or possibly fatal stroke. In fact, a few months ago she suffered a warning stroke.
"My legs started to get numb and my tongue got numb and my hands were shaking a lot," she says. "I did not know what was going on."
Fortunately, that stroke didn't leave her with lasting damage. But it heightened the urgency for an operation that Smith is preparing to do to stave off the almost inevitable.
Maribel's father, Luis Ramos, says they didn't hesitate to have the surgery Smith proposes. "We just want to fix it," he says. "We want to do whatever we can so it doesn't happen again. It's very scary."
Smith aims to give Maribel's brain a new blood supply.
It's an ingenious bit of surgery. He plans to take a fat, healthy blood vessel that now runs up the outside of Maribel's skull and reroute it so it's next to the section of her brain that's chronically starved for blood.
Once Maribel is asleep, Smith shaves a section of scalp behind her left ear and takes up a pencil-like wand. It uses ultrasound waves to locate the blood vessel, lying beneath skin and muscle, that Smith plans to use. He takes a marker and traces the vessel's path on her scalp so he knows exactly where it runs from her ear to the top of her head.
Next, Smith and surgeon Sarah Jernigan sit down next to Maribel's head and peer through a big microscope. Painstakingly, they slice through scalp and muscle. The pulsing artery comes into view.
Rare as moyamoya is, Smith operates on a child with the disease about once a week. And, much more often, doctors at Children's and other major pediatric hospitals see children suffering strokes for different reasons: other malformations of blood vessels in the brain; too little oxygen during birth; congenital heart defects; infections like meningitis and chickenpox. The cause is unknown in one-third of childhood strokes.
Pretty much every midsize town in America has at least one child who has suffered a stroke, Smith says as he works on Maribel. And the problem is growing.
"One of the newer conditions, unfortunately, that we think is becoming increasingly a cause for stroke in kids is the same cause that affects adults — obesity," he adds. "Kids are getting ... diabetes, blood pressure problems."
Finally, the surgeons have freed up the blood vessel that will be redirected underneath Maribel's skull to her oxygen-starved brain tissue. It looks like a jump rope that's 5 inches long. The ends are still attached and the middle part is free.
"That's the part we're going to swing under a piece of bone to put it in contact with the brain," Smith explains as he starts what he calls "the construction work."
"Kind of like digging a trough in the middle of downtown Boston," he says as he removes a section of Maribel's skull the diameter of a hockey puck. "It allows us to get this blood vessel where it's needed."
The blood vessel needs to be in direct contact with the brain. That involves removing the innermost protective layer, a cobwebby membrane called the arachnoid. When that's done, there it is: Maribel's exposed brain.
Next, Smith sews the blood vessel to the surface of the brain. This is the real key to the operation. Once the artery is in contact with the brain, it will start putting down new blood vessels, like roots from a tree.
"It's remarkable how quickly the brain can respond favorably to this graft when it really needs one," Smith says. In a sense, he's enabling Maribel's body to cure her moyamoya disease.
Once the new blood vessel is sewn firmly in place, the surgeons reverse course, carefully replacing layers of tissue one by one. Smith replaces the circle of bone, using tiny screws to fix it in place. He leaves two small holes so the rerouted artery can dive under Maribel's skull and exit on the other side. Finally, the soft tissue is replaced and the incision neatly sutured up.
"So, guys, we're done," he announces. And a few minutes later, Maribel is awake again — more or less.
"Hey, Maribel, hey, sweetie, it's Dr. Smith," he says. "Wiggle your toes, sweet pea. That's a good girl."
A few weeks later, I visit Maribel at home in Nashua, N.H. She's wearing an elaborate bow to hide the place where her hair hasn't grown in yet.
Her father says a recent MRI scan brought good news. "It was, what, two, three weeks after surgery, and you could already see the new veins growing into the brain," Luis Ramos says. "Everything looks good."
And now, instead of an almost 100 percent chance of a major stroke, Smith says Maribel's risk has been reduced drastically, to around 5 percent.
RENEE MONTAGNE, HOST:
This is MORNING EDITION from NPR News. I'm Renee Montagne.
DAVID GREENE, HOST:
And I'm David Greene.
The risk of suffering a stroke is pretty well known. Strokes are the third leading cause of death in adults. But today in Your Health, we're going to learn about a problem that is not as widely understood. And that is strokes in children.
MONTAGNE: Strokes affect one in 10,000 kids, a major cause of childhood death and disability. Childhood strokes have many different causes. Often there's nothing doctors can do except to try to minimize the damage and help the kids recover.
GREENE: This morning, NPR's Richard Knox tells us about how surgeons are actually preventing strokes in children who are at risk for one particular type. And just a quick warning. You'll be hearing graphic descriptions of a brain surgery as part of this story.
RICHARD KNOX, BYLINE: Maribel Ramos is 13 years old, and this fall she had a stroke.
MARIBEL RAMOS: My legs started getting numb and my tongue got numb and my hands were shaking a lot. I did not know what was going on. I was mostly in shock.
KNOX: Maribel has suffered from illness her entire life. She has sickle-cell disease. It's a painful blood disorder that affects about 100,000 Americans. It also increases the risk of stroke. For Maribel it's meant endless hospital stays.
RAMOS: I used to almost live in a hospital, they said.
KNOX: And she has another disorder that increases her risk even more.
DR. EDWARD SMITH: What we're looking at is what's called an angiogram. It's an X-ray picture of the brain.
KNOX: Dr. Ed Smith, a Boston neurosurgeon, is pointing to a black and white picture that looks like a tangle of angel-hair pasta.
SMITH: This is Maribel's angiogram picture from a couple of months ago.
KNOX: Oddly, her other disorder is called by the Japanese word Moyamoya. It means puff of smoke.
SMITH: If we follow this blood vessel up here, you see that right there it gets pinched off almost to nothing. And then this little puff of smoke right here, which are these little narrow blood vessels that don't fill the rest of the brain as it normally should.
KNOX: So her brain is really starved for oxygen then.
SMITH: Correct. And...
KNOX: All the time?
SMITH: All the time.
KNOX: These narrow blood vessels are prone to blood clots, especially in kids with sickle cell disease, which causes red blood cells to be spiky and misshapen. Maribel's stroke didn't cause lasting effects. But it's a harbinger of a major stroke that could cripple her for life, if it doesn't kill her. I met Maribel and her father, Luis Ramos, at Children's Hospital in Boston. He's a single father who devotes most of his life to caring for Maribel.
LUIS RAMOS: We're in the hospital for a week or two every other month or so.
KNOX: Over what period of time?
KNOX: Poor kid.
RAMOS: Yeah. She deals with it. She's very strong. But she's been through a lot.
KNOX: Usually she's in the hospital to manage the pain. But this time she's here to prep for an operation that Dr. Smith hopes will dramatically reduce her risk of a stroke. Maribel's nervous about it, for a reason any 13-year-old girl would understand.
RAMOS: It's a head surgery. I'm just like really nervous about how they're going to cut my hair and how - what people are going to say about it.
KNOX: But her father says they didn't hesitate to have the surgery.
RAMOS: Stroke is serious, you know? It's very serious. And we just want to fix it. We want to do whatever so it doesn't happen again. It's very scary.
(SOUNDBITE OF BEEPING)
UNIDENTIFIED MAN: Alright, Maribel.
UNIDENTIFIED WOMAN: Pick out a good dream.
UNIDENTIFIED MAN: Pick out a nice dream. Close your eyes.
UNIDENTIFIED WOMAN: Good job.
UNIDENTIFIED MAN: You're doing great.
KNOX: What Dr. Smith's going to do is give Maribel's brain a new blood supply. It's an ingenious bit of surgery. He plans to take a fat healthy blood vessel that now runs up the outside of Maribel's skull and re-route it so that it's right next to the section of her brain that's chronically starved for blood.
SMITH: You guys ready to turn the table?
UNIDENTIFIED WOMAN #2: Yes, sir.
SMITH: All right. Let's turn.
KNOX: Once Maribel's asleep, Smith positions her head and shaves a large patch of hair above her left ear. Underneath is the vessel he plans to use to bring the new blood supply to her brain. Next he takes up a wand the size of a pencil. It uses sound waves to locate the blood vessel underneath skin and muscle.
(SOUNDBITE OF HEARTBEAT)
SMITH: What we're hearing here is the heartbeat of the blood vessel we're going to use as a donor, I hope.
KNOX: He takes a marker and traces the vessel's path on her scalp so he knows exactly where it is. It runs from her ear to the top of her head.
SMITH: So it's 9:56. Ready to start. Starting.
KNOX: Smith and surgeon Sarah Jernigan sit down next to Maribel's head and peer through the eyepieces of a big microscope.
SMITH: Watch your eyes.
KNOX: Painstakingly they go through scalp and muscle. Slowly the pulsing artery comes into view.
SMITH: So you can see the blood vessel here.
KNOX: Smith operates on a kid with Moyamoya disease about once a week. Sickle cell disease is more common. And much more often doctors here see children suffering strokes for lots of different reasons - other malformations of blood vessels in the brain, too little oxygen during birth, congenital heart defects, infections like meningitis or chickenpox.
SMITH: One of the newer conditions, unfortunately, that we think is becoming increasingly a cause for stroke in kids is the same cause that affects adults - that's obesity. You know, kids are just getting fat. Diabetes, blood pressure problems.
Can you do a little suction up here, please, Sarah?
KNOX: Finally, the surgeons have freed up the blood vessel that will be re-routed underneath Maribel's skull to her oxygen-starved brain. It looks like a five-inch-long jump rope - the ends are still attached and the middle part is free.
SMITH: And that's the part we're going to swing under a piece of bone to put it in contact with the brain.
KNOX: Now Smith does what he calls the construction work.
SMITH: Move the bone out of the way - kind of like digging a trough in the middle of downtown Boston - and allow us to get this blood vessel where it's needed.
KNOX: The blood vessel needs to be in direct contact with the brain.
SMITH: So what we did now is we just opened the dura, the lining to the surface of the brain.
KNOX: The next part of the operation is especially delicate. The surgeons have to cut through the innermost protective layer. It's a cobwebby membrane called the arachnoid. When that's done, there it is - Maribel's exposed brain.
SMITH: This is a really cool part. I've probably done a couple thousand operations and it really is amazing. I mean this is where she speaks. This is where she understands a lot of things. This is what makes her move. This is what makes Maribel Maribel.
So what we're going to do now is sew this blood vessel to the surface of the brain. Take this please. Micro irrigation, please.
KNOX: This is the real key to the operation. Once the artery is in contact with the brain, it will start putting down new blood vessels, like roots from a tree.
SMITH: Blood vessels start to grow even within a few weeks after surgery. So it's remarkable how quickly the brain can respond favorably to this graft when it really needs one.
KNOX: In a real sense, Smith is just enabling Maribel's body itself to cure her moyamoya disease.
SMITH: You know, the disease is a horrible disease. But it's really enjoyable to try to trick the body into doing what you want it to do to try to help kids to get better.
Cut this please, right now.
KNOX: Once the new blood vessel is sewn firmly in place, the surgeons reverse course, carefully replacing layers of tissue, one by one.
SMITH: All right, that's beautiful.
KNOX: Next, Smith replaces the circle of bone. He leaves two small holes so the re-routed artery can dive under Maribel's skull and exit on the other side.
SMITH: So guys, we're done.
KNOX: And a few minutes later, Maribel's awake again - sort of.
SMITH: Hey, Maribel? Hey, sweetie. It's Dr. Smith. Can you hear me? Hey, Maribel, honey, wiggle your toes, sweet pea. Does that hurt? Yeah? I'm sorry. Can you wiggle your feet for me, sweetheart? That's a good girl.
KNOX: A few weeks later, I visited her at home in Nashua, New Hampshire.
So how are you?
KNOX: She's wearing an elaborate bow to hide the place where her hair hasn't grown in yet.
RAMOS: I've been trying to cover it up so nobody could see it. Yeah.
KNOX: It's not that noticeable. Is it better or worse than you thought it was going to be?
RAMOS: It's in the middle.
KNOX: Her father says a recent MRI scan brought good news.
RAMOS: It was, two, three weeks after surgery and you could already see the new veins growing into the brain and everything looks good.
KNOX: Before the surgery, Dr. Smith says Maribel was virtually certain to have a major stroke, a 95 percent chance, in fact. But now her risk has been reduced drastically, to around five percent.
Richard Knox, NPR News, Boston. Transcript provided by NPR, Copyright NPR.