STANFORD, Calif.— If Barbara Maluo's brain aneurysm had been discovered a few months ago, she would have had few viable treatment options. She was one of the 10 to 15 percent of brain aneurysm patients diagnosed each year with aneurysms so large and wide that they cannot be reliably treated using conventional methods of treatment.
Fortunately, time was on Maluo's side. The discovery of a bulge in her carotid artery came after the Food and Drug Administration fast-tracked approval of a brand-new intracranial device called the Pipeline stent. This week, Stanford Hospital became the first hospital in Northern California—and one of only two in the state—qualified to offer the Pipeline treatment without restrictions. Maluo was one of Stanford's first Pipeline patients.
The FDA has limited the Pipeline for use on aneurysms in the internal carotid artery, the major blood vessel supplying blood to the front of the brain. "We know that the device is safe in certain anatomy, like the carotid," said Michael Marks, MD, chief of Stanford's Interventional Neuroradiology Department. "The carotid is also one of the most common sites for these large aneurysms to occur. As we learn more, there may be additional applications for a device like this. But our focus right now is treating those patients that we've had no good treatment for."
Maluo was first diagnosed with the aneurysm after going to a hospital in Hilo, Hawaii. She had reacted badly to some pain medication and was so "loopy," she said, that doctors did a quick brain scan on her. That's when they discovered the large bulge in her carotid artery. Maluo's doctor sent her angiogram images by iPhone to Marks, who examined them and realized she would be good candidate for the Pipeline.
A few days later, Maluo was at Stanford Hospital, ready for her procedure. Through a small incision in her groin, Marks threaded in a catheter along a path through Maluo's blood vessels to help carry the Pipeline to her brain.
Aneurysms occur when blood vessel walls weaken, causing them to balloon out. People may walk around with brain aneurysms for years without symptoms. The threat is that they will burst; the bleeding that follows can be lethal. An estimated 6 million people in the United States (about one in 50) have a brain aneurysm. Some 25,000 to 30,000 people every year experience hemorrhages from a burst aneurysm; about 40 percent do not survive.
Some aneurysms are small and can be treated either by filling them up with coils inserted through a catheter in a minimally invasive procedure, or through neurosurgery that opens the skull, clamping them off with clips. Some smaller aneurysms with wider necks can also be treated with coils and stents developed especially to keep the coils from falling into the main artery.
Others, like Maluo's, are so big and wide that coils and standard stents are not adequate. In such cases, these traditional procedures carry a higher risk and have a lower chance of success.
At first glance, the Pipeline looks like a standard intracranial stent used with coils, but its distinctive design eliminates the need for coils, which are used to fill a brain aneurysm to block blood flow. The Pipeline's netting is braided, with 48 strands interlocked into a dense weave. Introduced into the artery through a microcatheter less than 0.027 inches in diameter, the Pipeline is placed to precisely expand and cover over the neck or opening of the aneurysm. Its braided walls diminish the flow of blood into the aneurysm, sealing it off while still allowing blood to flow freely through the healthy part of the artery.
The blood in the aneurysm clots, blocking the aneurysm's ability to expand or rupture. The Pipeline allows all the blood vessels in the area to remain functional. "You really don't want to sacrifice a major blood vessel," Marks said.
The new device was originally developed by a Menlo Park-based company, and its clinical success won FDA approval after just a year's use in Europe. "It was a very fast turnaround," Marks said. "This stent was recognized as a treatment for a group of patients who did not have any good treatment options".
Maluo was out of the hospital quickly. "It's kind of amazing to know that they were in there working on your brain and you're out in two days," she said. "I am just overjoyed to get it treated so quickly." She has since returned to Hawaii, her life-threatening aneurysm safely sidelined.
By Sara Wykes