Endovascular Neurospecialists at two Portland hospitals are starting to use a new stent -- a scaffolding that supports blood vessels -- to fix a category of potentially deadly brain aneurysm.

The device promises to help doctors repair "wide-necked" aneurysms, or swollen spots in blood vessel walls that balloon and sometimes burst, causing a stroke. This type is tough to treat with the method surgeons increasingly prefer: filling the aneurysm with platinum coils that absorb the pressure of blood pumping against the weakened vessel wall.

"It's almost more like a wide-mouthed pickle bottle than a ketchup bottle," said Dr. David Siker, an Internal Neuroendovascular Surgeon at Legacy Emanuel Hospital & Health Center in Portland. "There are a whole bunch of aneurysms that have this shape. . . . That's a huge problem."

When doctors put coils in wide-necked aneurysms, they are more likely to sink back into the vessel, where they can block blood flow to the brain entirely and cause a stroke. The stent provides a sort of scaffolding that hugs the inside of blood vessel walls and straddles the neck of the aneurysm, keeping coils from entering the vessel.

"It allows better packing of the aneurysm" with coils, said Dr. Stan Barnwell, an endovascular neurosurgeon at Oregon Health & Science University. "It's potentially a very important advance in the treatment of aneurysms."

Siker said that roughly a third of aneurysms are "wide-necked." The Boston-based Brain Aneurysm Foundation estimates that about 2 million U.S. residents have a brain aneurysm, roughly 30,000 of whom suffer a ruptured aneurysm each year. About half of people with ruptured aneurysms die within a few months.

The U.S. Food and Drug Administration approved the novel Neuroform stent last fall as a "humanitarian use device." Those are devices that aim to treat problems with no equally good existing treatment, but which haven't been tested as extensively as most new devices. They must be used with special oversight from hospitals.

Between Legacy Emanuel and OHSU, local surgeons have used the device roughly 14 times since the winter. The device is expensive: about $3,800 per stent, Siker said. And its manufacturer, Boston Scientific, is working to find ways to ease its sometimes-difficult installation, Barnwell said. Both surgeons said they are generally optimistic about the device, which furthers a trend toward newer, less-invasive methods of treating aneurysms from the inside of blood vessels, called endovascular surgery.

From the late 1930s until recently, surgeons generally treated aneurysms by opening the skull and moving aside brain tissue to expose the ballooning vessel. They put a metal clip on either side of the aneurysm neck and pinched it closed, keeping the main blood vessel open. Then they had to close the skull and scalp. The surgery took hours, but generally had a favorable outcome -- significant since a brain aneurysm is very serious, and aneurysms that break are fatal about half the time.

In the early 1990s, however, some U.S. doctors started experimenting with a less invasive way of treating aneurysms. They fed small catheters through large blood vessels, such as those running near the groin, through the circulatory system into the brain. Then they pushed coils made largely of platinum through the catheter, packing the aneurysm as tightly as possible. The coils absorb the force of blood pumping through the vessel, protecting the weak walls of the aneurysm and heading off ruptures, Siker said.

U.S. surgeons increasingly used coils throughout the 1990s, Siker said. A randomized trial published last year showed that, among patients with ruptured aneurysms, those treated with coils were 22.6 percent less likely to be disabled or dead one year after surgery than those treated with clips.

"Now we all feel this huge shift. Everybody feels it (coiling) is the way to go," in most cases, Siker said.

Wide-necked aneurysms presented a problem, however -- it wasn't harder to get the coil in them, but hard to keep it in place. Neurosurgeons tried to use expandable balloons and other methods to help fix the coils for a time. And they soon turned to stents -- which were widely used for repairing heart vessels.

Coronary stent too big But "taking a coronary stent and putting it in the brain is like taking an 18-wheeler and putting it on a bike path," Siker said. "It's physically challenging. It stresses the vessels. It's not what the coronary stents were designed to do."

Coronary stents are commonly used to prop open narrowed vessels, and they are "stiffer and require higher pressure to deploy" than the Neuroform, Barnwell said. It is designed to be softer on delicate brain vessels, and to have larger holes. Barnwell said OHSU neurosurgeons have been using the stent since December and have treated about 10 patients.

To use the Neuroform, doctors feed the stent, enclosed in a small sleeve, through vessels to the site of the aneurysm. As they pull back the sleeve, the stent expands until it touches the side of the vessel. The surgeon then threads a catheter through a hole in the stent into the aneurysm and fills it with the platinum coil. The stent holds the coil in and lets surgeons pack it tightly.

Stents used in cardiac surgery bring a risk of renewed blockage, with material gathering around the stent and further narrowing the vessel. But animal tests of the Neuroform stent, and its human uses so far, indicate that narrowing vessels aren't a problem with the Neuroform, Siker said, because the brain vessel with an aneurysm usually is not suffering from the process that affects the narrowing heart vessels.

Siker said he has performed four such operations and has two more scheduled this month. He's so excited about the technique that he is reviewing the files of patients he previously told he couldn't treat with coiling, to see whether he can treat them with the Neuroform. Roughly half of those patients seem like they might be candidates for the stent-and-coil surgery, he said.

Kathy Railing, of Vancouver was one of those patients. Railing, 48, started having headaches in August 2000 and collapsed on September 11 of that year.

She found her way to Siker, who discovered that she had a ruptured aneurysm in the base of her skull, near her brain stem. The aneurysm had a wide neck and two separate bubbles, instead of one. The location made surgery to clip the aneurysm very risky, so Siker tried to fill it with coils, using a soft balloon to create a "temporary scaffold" while he stuffed the coils in. That way, Siker said, he used coil to fill "about 90 percent of the aneurysm, and saved her life."

It took months for Railing to get over the surgery and other problems related to the aneurysm. But she said she was able to lead a fairly normal life -- with one glaring exception. "I had a headache every day," she said. "I functioned, but I functioned by taking 1,500 to 2,000 milligrams a day of Extra Strength Tylenol. . . . I functioned but I was pretty grumpy."

Early this year, Siker called Railing back and told her he might be able to use the stent to pack her aneurysm more completely with coil. She decided to go in for the surgery, which took place on Valentine's Day.

"I was home the next day and I haven't had a headache since," she said. "I'm so lucky." Andy Dworkin: 503-221-8239; andydworkin@news.oregonian.com