OU Medicine Neurosurgeon First To Use Lifesaving Stent on Aneurysms

Aneurysms in the brain are dangerous because, if they rupture, patients face a significant chance of dying within six months. To decrease that possibility, OU Medicine neurosurgeons are using a new medical device to prevent aneurysm rupture and recurrence -- without major surgery opening a patient’s skull.

Neurosurgeon Bradley Bohnstedt, M.D., has been using the Surpass Streamline Stent to divert the flow of blood away from an aneurysm, which greatly decreases its potential for rupture. The procedure is minimally invasive – via a catheter, the stent is inserted into a blood vessel near the groin, then Bohnstedt directs it all the way up to the aneurysm in the brain.

OU Medicine was the first in Oklahoma to place the Surpass Stent in a patient. The advantage of the device is that it is designed to treat larger aneurysms in more areas of the brain. The technology is called “flow diversion” for its ability to route blood away from the aneurysm.

“By diverting the flow of blood away from the aneurysm, it reduces the stress on the wall of the aneurysm and allows it to heal and shrink,” Bohnstedt said. “In six months to a year, the aneurysm takes on the normal shape of the blood vessel.”

Bohnstedt describes aneurysms as blisters on the side of a blood vessel. If an aneurysm ruptures, 10 percent of patients will die before they make it to a hospital. Up to 50 percent of people whose aneurysms rupture will die by six months because of ensuing complications, Bohnstedt said.

Because of readily available imaging techniques, physicians are finding more aneurysms today than ever before. Some aneurysms are small and never need to be treated, Bohnstedt said, but others are risky to the patient.

“It’s important when we identify aneurysms that we stratify their risk for rupture to determine which ones need to be treated,” he said. “Then we want to treat them sooner rather than later.”

The treatment of aneurysms has evolved as technology has improved. Traditionally, Bohnstedt would open up the patient’s skull and place a clip on the aneurysm to prevent its rupture. He still performs that surgery when necessary but, while effective, it is invasive and leads to a long recovery for the patient. With the advent of endovascular techniques, neurosurgeons gained a minimally invasive method of accessing an aneurysm by traveling through the blood vessels. The first and second generations of endovascular treatment involved placing coils made of platinum inside the aneurysm to keep the blood flow at bay. With this technique, patients faced far less recovery time, but the aneurysms recurred about 40 percent of the time. The Surpass Stent, made of metal, is greatly improved in all areas – it works well for larger, more distant aneurysms and, once treated, they don’t seem to return.

“We’re treating far more aneurysms with the Surpass Stent than we previously treated,” Bohnstedt said. “We also hope to be involved with the study for the next generation of the Surpass device, which will have the ability to treat even more sizes of aneurysms in additional parts of the brain. OU has been an early adopter of new technologies after FDA approval, which allows our patients to be a part of research studies for devices that aren’t readily available to the public.”