Press Release

Experience Counts in Moyamoya Disease Care


Even as a small child, Tara MacInnes, now 27, had headaches, bad ones that felt like a vice grip at her temples. "They were excruciatingly painful," she said. By the time she was eight, she could better describe them to her mother—and her other symptoms, too. "I'd feel a tingling sensation, numbness in my hands and face and sometimes my legs," she said, "but my pediatric neurologist wrote those off as being additional migraine symptoms that many migraine sufferers experience." What she came to call episodes continued into her teen years, sometimes lasting minutes and sometimes affecting her speech.

Then came an episode of frightening proportions. She was 16, out to a meal with her parents. "My entire right arm went numb, the fork I was holding fell to the floor, and the numbing sensation traveled all the way down the right side of my body," she said. "I had no sensation of that half of my body, and my speech was entirely gone." This episode lasted longer than most, at least 10 minutes. "I was terrified," she said.

MacInnes was sent for an MRI. The images showed damage from strokes on both sides of her brain—and soon after, she was diagnosed with a rare cerebrovascular disease called Moyamoya disease. The disease takes its name from the Japanese word for puff of smoke. Moyamoya disease blocks arteries near the base of the brain, forcing smaller blood vessels to expand in number as the body attempts to maintain adequate blood flow. The clusters of those smaller blood vessels can look like puffs of smoke. The condition is progressive and there is no cure. Neurosurgeons, however, can do a workaround, using arteries from the scalp to bypass the one blocked by Moyamoya disease. Those bypass arteries restore proper function at what is effectively a "switching station" for blood to move into the entire brain.

The right treatment for Moyamoya disease

It's a surgery that requires the utmost of precision, requiring a needle as tiny as an eyelash and sutures smaller than a human hair. It is not a procedure to be done by a neurosurgeon without much experience. What helped MacInnes' parents accept such a surgery was the information their daughter's neurologist shared. "You're very fortunate," MacInnes' mother Jill remembers him saying. "There are just a couple of experts in the country, and one of them happens to be at Stanford. I've already put in a call to him." Fifteen minutes later, MacInnes' parents' phone rang. It was Gary Steinberg, MD, PhD. "Although we'd been given this very, very scary diagnosis," Jill MacInnes said, "we felt some relief knowing that these people at Stanford knew what they were doing." 


Steinberg, director of the Stanford Moyamoya Center and chair of Stanford's Department of Neurosurgery, had already had 13 years of Moyamoya disease surgery experience when he made that call to the MacInnes family in 2004. Now, Steinberg has treated 720 patients from around the world and completed 1,177 bypass procedures. That history ranks Steinberg as one of the world's most experienced Moyamoya disease surgeons. His is the largest Moyamoya disease practice in the world.

"Tara is a typical Moyamoya disease patient in many respects," Steinberg said. "She'd had migraines since early childhood and she'd had multiple undiagnosed strokes on both sides of her brain. Then, at 16, she had an unusual episode of numbness in her right hand and arm, lasting about 15 to 20 minutes, unlike anything she had previously experienced."

The neurologist who sent her for an MRI scan was astute, Steinberg said, because that test revealed the previous strokes and showed the blood vessels at the base of the brain were not filling properly. An angiogram, which uses a special camera and dye to illuminate blood flow, showed that her carotid arteries were also blocked, another characteristic of Moyamoya disease.

"What we want to convey to neurologists and other physicians is that they should consider moyamoya, particularly in young patients, who present with unusual headaches," Steinberg said. "It's much more common than we once thought. It's definitely underdiagnosed in the United States and there's a huge advantage to diagnosing and treating patients before they develop significant strokes that can impair the rest of their lives. Some may not survive those strokes." Without correct diagnosis and quick treatment, Steinberg said, studies have shown that strokes experienced by patients with Moyamoya disease become progressively more severe.

Moyamoya disease needs more than medicine

Even before there was an official Stanford Moyamoya Center, Steinberg and his team recognized that their Moyamoya disease patients needed more than a surgical procedure. "We found our patients really benefitted from a well-rounded treatment plan," said Teresa Bell-Stephens, an RN who has worked with Steinberg since his first Moyamoya disease surgery in 1991.


Because he was treating so many people with this rare condition, Steinberg began to collect Moyamoya-altered tissue, blood and cerebral fluid to conduct analysis that might lead to better understanding and treatment of the rare condition. Steinberg and his colleagues suspected the disease had a partial genetic basis, when they noticed that about 10 percent of Stanford’s patients had moyamoya in their families.

When technology finally allowed a genetic analysis of that material, Steinberg's research group discovered some novel genetic mutations that predispose to developing Moyamoya disease. His research continues, using that tissue bank, which dates back to 1995, to develop a deeper knowledge that could lead to more effective treatments, including non-surgical approaches.

Annual reunions for Stanford's moyamoya patients and their families began in 2005. "Many moyamoya patients feel like they have been turned away by the medical community," Bell-Stephens said, "and when they finally feel like they belong somewhere, they feel like they are part of a family, with each other and with our staff. I always say our patients don't come and have surgery and leave, they become part of the program—they are here for the long haul—and I think that gives them a greater sense of security. We tell them, 'We are not going to let you go.'"

That's been especially true for MacInnes and her family. Jill MacInnes is the Stanford Moyamoya Center's patient advocate, a job she is happy to do. When Tara had her surgeries, there were no organized ways for her mother to talk with other families who had gone through the difficult experience, especially the six-hour long wait for word of an outcome. "It was the most painful thing I'd ever gone through," she said. Now, she helps patients through every step of the process. Moyamoya patients and their families now help each other, too, to answer common questions about what life will be like after surgery. "We didn't want people to be alone," Jill MacInnes said. "Now, seeing patients come together to offer each other support has been amazing." Adding social media, including a Facebook group, has developed an even larger extended support system for patients and their families.

Educating others about Moyamoya disease

Her daughter became a devoted advocate, too. Within a year of the completion of her surgeries, she was volunteering at the Stanford Moyamoya Center, talking with patients and their families. Now studying for a master's degree in counseling, her most ambitious goal is to create an official worldwide moyamoya day. When she first began to talk others about moyamoya disease, she discovered it wasn't just the general public that didn't know much about the disease. "I found a persistent need to educate medical professionals, too," she said. "I consider myself fortunate if I talk to 50 people about moyamoya disease and one of them has heard of it. It's been a definite fight and it's what's kept me determined to raise awareness." 


After police pulled over a woman driving across the Golden Gate Bridge in a way they thought was influenced by alcohol, doctors later discovered that her behavior was driven by a hemorrhage in her brain, initially thought to be caused by an arterial venous malformation (AVM), another form of vascular disruption.

"When we looked closer," Steinberg said, "we discovered that it was not the AVM causing the bleeding but Moyamoya-affected vessels near the AVM." That patient lead to others and one of those early patients created a website on the condition to alert others. "Our patients have been a great source of increasing awareness and support to each other," Steinberg said.

With patients, she's even more forthright. "They say to me, 'I hope this isn't too personal' and I say, 'Bring it on.' When I had my surgeries, we had all the answers we needed from the medical side, but we never got to hear those personal success stories from the patient's side of things." That would have been important, she thinks. For years, she had struggled in school, not knowing that some of that struggle was caused by her strokes. One motivation for that World Moyamoya Day is to prevent others from experiencing the same sort of cognitive loss. "Unfortunately, a large number of people aren't diagnosed with moyamoya disease until they've had a massive stroke or hemorrhage," she said. "Not enough medical professionals are aware of it. The national medical board and national nursing board exams don’t require knowledge of moyamoya disease."

She doesn't have a set speech she makes when she talks to others about Moyamoya disease. "If my education comes up, I'll say I'm pursing my master's degree, but I also want to start a medical non-profit. They say, 'Why,' and I'll say, 'I'm glad you asked.'"

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