UCI Health neurosurgeon first on West Coast to use new brain aneurysm stent

Surpass, flow diversion offer improvements over existing treatments

April 04, 2019
UCI Health neurosurgeon Li-Mei Lin, MD
UCI Health neurosurgeon Li-Mei Lin, MD

 UCI Health neurosurgeon Li-Mei Lin, MD, is among the first in the U.S. to use the latest minimally invasive device to treat large brain aneurysms that reduces the chance of rupture or recurrence.

Flow diversion is a new technique for the endovascular treatment of aneurysms that addresses the shortcomings of current procedures, such as surgical clipping and coiling. A recently-approved FDA stent called Surpass allows Lin to treat larger aneurysms than does coiling, a popular endovascular treatment in which a wire is threaded through a catheter into the aneurysm sac or bubble, sealing it from the main artery.

Despite technological advances, coiling can have recurrence rates as high as 20%, particularly for large and giant aneurysms measuring greater than 10mm. Lin said flow diversion offers numerous improvements.

“Placing a high-density mesh stent, or flow diverter, into the parent vessel blocks blood from reentering the aneurysm,” said Lin, an assistant professor in the Department of Neurological Surgery, UCI School of Medicine. “The procedure effectively heals the diseased blood vessel as the flow diverter stent also provides a scaffold for the growth of new blood vessel cells, called endothelium. This seals the aneurysm off from the main artery.”

UCI Health offers the widest available range of aneurysm treatments, from the traditional surgical clipping, which requires cutting through the skull, to endovascular treatments such as coiling and flow diversion, in which a catheter inserted through an artery is threaded into the brain to repair the aneurysm.

Effective use of the flow diversion procedure requires a new set of skills, Lin said. As neurovascular surgeons develop expertise, more patients will have expanded treatment options, Lin said.

“This technique of blood flow modulation with braided mesh devices is the future of aneurysm treatment and repair,” she said. “Nationally, we now see that a third of aneurysms are treated with flow diversion, a third with coiling/stent-coiling and a third – or less – with surgical clipping.”

Lin, who travels the country to teach surgeons and proctor the use Medtronic Pipeline Endovascular Device and the newer Stryker Surpass flow diversion stents, treats up to 150 aneurysms annually. In December, she performed the first Surpass procedures on the West Coast, treating five patients including a man whose aneurysm could not be treated using the Pipeline device or the traditional coiling or surgical clipping options. Another patient, who had undergone a flow diversion procedure with Lin during the initial clinical trials for Surpass in 2015, had an additional aneurysm on the opposite side of the brain and underwent successful treatment with the Surpass stent.

“We assess each patient’s condition and determine which treatment best meets their needs,” Lin said.

What is a brain aneurysm?

“A brain aneurysm forms from a weakened area of an artery in the brain resulting in an abnormal balloon/bulge that can burst and cause life-threatening hemorrhage in the brain,” Lin said.

Aneurysms most commonly occur in adults between the ages of 40 and 60, however they may occur at any age, she said. Women are most commonly affected. Most unruptured aneurysms do not produce any symptoms despite the risk of rupture, she said. Larger aneurysms can cause symptoms associated with pressure on surrounding brain or nerves such as seizures, abnormal eye movements or headaches.

According to the Brain Aneurysm Foundation, approximately 6 million people in the United States have an unruptured brain aneurysm and about 30,000 are treated with endovascular or surgical treatments each year.

Lin is the leading brain aneurysm expert in Orange County, Calif., having trained in both vascular neurosurgery and neurointervention. She is a national expert on minimally invasive brain aneurysm treatments, including flow diversion and serves as a proctor for both PED and Surpass devices. She is currently the only specialist in Orange County able to offer these newest endovascular treatments for brain aneurysms.

UCI Health comprises the clinical enterprise of the University of California, Irvine. Patients can access UCI Health at primary and specialty care offices across Orange County and at its main campus, UCI Medical Center in Orange, California. The 417-bed acute care hospital provides tertiary and quaternary care, ambulatory and specialty medical clinics, and behavioral health and rehabilitation services. UCI Medical Center features Orange County’s only National Cancer Institute-designated comprehensive cancer center, high-risk perinatal/neonatal program and American College of Surgeons-verified Level I adult and Level II pediatric trauma center and regional burn center. UCI Health serves a region of nearly 4 million people in Orange County, western Riverside County and southeast Los Angeles County. Follow us on Facebook and Twitter.

View by Category