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TECHNIQUE HERE TREATS ANEURYSMS WITHOUT SURGERY

Brain surgery has been the bedrock method to prevent strokes -- open the hood, lift the engine and put a clip on the weak spot of a blood vessel before it bursts and bleeds.

Now, in a major advance, Buffalo researchers have developed a method that avoids surgery altogether. They have inserted a flexible metal sleeve the size of thin spaghetti into the brains of several patients to prop up faulty blood vessels.

"Medicine is on the verge of beating stroke," said Dr. L. Nelson Hopkins, the neurosurgeon who is leading the research effort. "We're not going to be opening up the skull in the future. We're going to rebuild arteries from the inside."

The experimental technique promises a better alternative and perhaps a replacement for surgery. It is considered an improvement over another procedure, using tiny coils to clot the abnormal bulges in artery walls, called aneurysms. Under that method, fewer than half of the procedures end in complete success.

An aneurysm is like a blister on a blood vessel. It may look like a bulge. Or, it can form a balloon-like sack with a narrow opening.

Aneurysms can occur anywhere in the body, but those that burst and bleed in the brain often kill or cause severe disability. About 30,000 Americans suffer such hemorrhagic strokes each year, and more than half of them die within a month.

A major rupture often is preceded by a "warning leak" or small hemorrhage. It feels like the mother of all headaches.

That's what Donald Heckman remembers about the night of Jan. 4, 1996.

He was home alone in Queensbury when an explosive pain hit his head so hard he fell to the bed and lay there unable to move. CT scans by doctors in Albany located an aneurysm surrounded by a mass of nerves and arteries deep in the stem of his brain.

Surgery isn't always possible because the aneurysm can be inaccessible or too big, or the patient may be too ill.

Unable to help Heckman, the Albany doctors sent him to Hopkins at Millard Fillmore Hospital, now a part of the CGF Health System. Hopkins was among a handful of surgeons using new Guglielmi detachable coils.

Named after its developer, Dr. Guido Guglielmi of the University at California at Los Angeles, the therapy involves inserting a catheter in the upper leg through which a hair-thin coil is packed into an aneurysm. The coil is given an electrical charge, causing it to detach and seal off the bulge from the affected artery.

But like surgery, the coils have limitations. They often compress, and the aneurysm grows.

Heckman's aneurysm looked like an upside down ice cream cone -- a big opening that tapered to a point -- and Hopkins did his best to seal it off.

"It was good enough to send me home but not perfect," said Heckman, 55, whose family owns six radio stations in the Glens Falls region. "Dr.
Hopkins told me he was working on something that would be perfect. It was just a few years away."

Heckman reminded Hopkins of that statement earlier this month after a diagnostic test showed his aneurysm had grown, creating a time bomb for a stroke.

He returned to Buffalo on Aug. 13, and Hopkins was ready. The month before, the Food and Drug Administration had been persuaded to allow his research team to use a device called a stent.

Stents -- tiny tubes made of a variety of materials -- are being used by surgeons to hold open arteries around the heart. A few physicians, including Hopkins, have tried coronary stents in the brain.

But the FDA decision cleared the way for Hopkins to try the first stent made specifically for the brain on five patients.

It's not a minor difference. A brain stent required technological leaps that took years to achieve.

"The arteries in the brain are more fragile, the walls thinner, the routes they follow so much more tortuous," said Hopkins, professor and chairman of neurosurgery at the University at Buffalo. "Coronary stents are used to unclog an artery. We were looking to rebuild an artery that had a hole in it or that was torn."

A miniature plastic straw would not do.

To begin with, brain stents must be ever so small, soft and flexible, like a piece of yarn, yet strong enough to keep a blood vessel open. The stainless steel wire filaments that form the first stent devised by the Buffalo researchers are 3/1 ,000 of an inch wide.

Brain stents must be porous like a chain-link fence; otherwise, they'd block the tiny branch vessels that line cerebral arteries like the hairs on a plant's root. And, they must restore normal blood flow in the artery while diverting blood from the whirling vortex of blood in the aneurysm.

"Our idea was to create a scaffolding in the artery that would act like a breakwall," said Ajay Wakhloo, a neuroradiologist whom Hopkins credits with coming up with the idea for their brain stent four years ago. "Just as the wall in water breaks the energy of waves, the stent would break the energy of the blood rushing in and out of the aneurysm."

Wakhloo, an expert in blood flow, said one of the biggest obstacles confronting researchers is that cerebral aneurysms come in different sizes, shapes and places, each with a unique set of conditions. That suggests brain stents will have to be tailored to the environment in which they will be placed.

The investigational brain stent the Buffalo researchers devised, which was manufactured for them by Arterial Vascular Engineering Inc. in Santa Rosa, Calif., went into the first patient on July 30 -- a 48-year-old housewife from Winchester, Ky.

Loretta Ralston's doctors sent her to Hopkins after they found two difficult aneurysms in her brain, one directly under each eye socket. Hopkins offered her brain surgery that would involve taking the bottom part of her skull apart and a week-long hospital stay or the experimental stent.

"I didn't really see it as a choice," said Mrs. Ralston. She ended up heading back home two days after the procedure.

On Aug. 13, Hopkins' team placed the stent successfully in a second patient -- Heckman.

The procedure resembles angioplasty, the now-commonplace technique to open blocked arteries by passing tiny inflated balloons through a catheter.

In the operating room, most of the action takes place near the patient's groin.

A catheter, a long, flexible plastic tube, is inserted in the upper leg to gain access to a major blood vessel. Physicians use the blood vessels like a super highway, snaking the catheter up through the body into the brain and watching their actions on real-time X-rays to guide them.

The catheter serves as a tunnel through which they will do their work.

Hopkins manipulates a guidewire through the catheter and past the aneurysm. The stent, which is wrapped tightly around a tiny balloon, is advanced over the wire. The device is so small it appears as a shadow on X-ray. Hopkins must position it by watching markers inscribed on the balloon.

He deploys the stent by inflating the balloon gently with a dye that makes the blood vessels stand out on the screen. There's no room for error.

"You've got to be exact," Hopkins said. "You only get one shot."

The goal of the procedure is to divert blood flow away from the aneurysm and prod the body to naturally clot the abnormal bulge in the vessel. If that doesn't occur, the aneurysm can easily be filled with the tiny platinum coils in a later procedure, with the stent acting as a buttress and containing the coils within the aneurysm wall.

"This is cutting-edge stuff. It's the direction we will go in and may become the standard if it holds up over time," said Dr. Warren Selman, director of the Center for Stroke at Case Western Reserve and University Hospitals of Cleveland.

But a handful of technological problems remain.

Other scientists are working on safer ways of delivering brain stents other than by balloon, perhaps a device controlled by a joystick through a magnetic field.

Of greatest concern is the long-term effectiveness of the stents: Will the metal fatigue from the constant rush of blood?

Stent materials must be more flexible and biologically compatible with the body. Hopkins and his team at the Toshiba Stroke Research Center at UB plan to use nitinol next, a "shape-memory" nickel-titanium alloy used in some heart stents and those eyeglass frames that revert to their original shape after being crazily twisted.

"We're working toward a minimally invasive cure for stroke," Hopkins said. "The technology is still crude, but the concept of rebuilding arteries from the inside is here."

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