News | News By Subject | News by Disease News By Date | Search News
Get Our FREE
Industry eNewsletter

ASITN Release: Study Results For Recently Approved Device To Treat Serious Brain Vascular Disorder Announced At International Meeting

10/19/2005 5:09:06 PM

OAHU, Hawaii, Aug. 5 /PRNewswire/ -- Study results for the recent FDA- approved Onyx(R) Liquid Embolic System (Onyx) were announced today at the American Society of Interventional and Therapeutic Neuroradiology (ASITN) Annual Meeting in Oahu, Hawaii. The first liquid polymer material on the market indicated for pre-surgical treatment of arterio-venous malformations (AVMs), Onyx will provide neurointerventionists across the United States with a valuable treatment option. Under development since 1995, the device is manufactured by Micro Therapeutics, Inc. (MTI).

AVMs are abnormal blood vessel networks that result in unusually high blood flow between arteries and veins in the brain. The resulting pressure imbalances caused by the increased blood flow puts the malformed blood vessels at serious risk for hemorrhage or rupture, which can lead to stroke, severe disability or death. Onyx is utilized by neurovascular specialists, including interventional neuroradiologists, to block or fill in the abnormal blood vessel connections in order to reduce pressure and significantly decrease the risk of bleeding.

According to Gary Duckwiler, M.D., Principal Investigator for the study at University of California at Los Angeles and president of the American Society of Interventional and Therapeutic Neuroradiology (ASITN), "The study results show that Onyx is a safe medial device that gives physicians a valuable treatment option that can result in better patient outcomes."

The study results were obtained from a multi-center, randomized study including 108 patients treated at 20 U.S. hospitals. Patients presenting as asymptomatic and symptomatic were included. Final results indicated that the Onyx(R) Liquid Embolic System met the efficacy and safety endpoints of the study, meaning that Onyx is as safe as the current standard of care.

Physicians participating in the study delivered the Onyx material directly to the AVM in the brain using standard catheter-based therapy. Under radiological guidance, a catheter is inserted into the groin and routed through the blood vessels leading to the brain. Onyx is then introduced through the catheter directly to the targeted area. Once injected into the appropriate vessels, the Onyx material quickly transforms into a solid polymer cast, thereby sealing off the vessels in the AVM from blood flow and reducing the risk of rupture.

According to Duckwiler, Onyx does provide physicians with some significant advantages in the treatment process. Because the material is non-adherent and won't stick to the catheter (sticking results in immediate halt to treatment), the physician is not forced to work as quickly once the material is injected. This extended working time, in turn, enables the physician to control the delivery of the material to the abnormal blood vessels, monitor the ongoing therapy as it is in process and inject and occlude (block) larger portions of the AVM than was previously possible.

AVMs are believed to affect approximately 300,000 Americans, occurring in males and females of all ethnicities and races at equal rates. Many patients don't even know they have an AVM, while in other cases, patients experience symptoms including headaches and seizures.


ASITN members specialize in minimally invasive and endovascular procedures to treat stroke, aneurysms, arterio-venous malformations, carotid stenosis and spine fractures. Our physicians have made numerous contributions to the neurosciences including: advancing stroke treatment through catheter-based therapy; innovating endovascular coiling for aneurysms; pioneering interventional procedures to treat fractures in the spine; and initiating the first-ever stroke registry to track procedural success in the treatment of acute stroke. More information on ASITN and our members' treatment specialties may be found at .

American Society of Interventional and Therapeutic Neuroradiology

CONTACT: Rebecca Hall, Media Relations, of ASITN, +1-305-519-2094,

Read at

comments powered by Disqus