Minimally Invasive Aneurysm Treatment Yields Successful Long-Term Results
Coiling, a minimally invasive procedure to treat aneurysms in the brain, is successful in preventing recurrent or first-time bleeding years after initial treatment in those aneurysms considered "untouchable" by the traditional surgical option.
One of the most significant findings since the 2002 release of the International Subarachnoid Aneurysm Trial or ISAT (the trial that established coiling as a safe and effective treatment), this new study's scientific value is reflected in its large patient population and length of post-procedural follow-up -- two factors that have not existed together in other post-ISAT studies to date. Results were unveiled yesterday at the fourth Annual Meeting of the American Society of Interventional & Therapeutic Neuroradiology (ASITN) in Dana Point, California.
"This study represents a unique contribution to the scientific evidence that proves coiling to be a viable treatment option," said study presenter Jo Peluso, a neurointerventional radiologist who collected and analyzed the data on behalf of colleagues W.J.J. van Rooij and M. Sluzewski, who have been performing neurointerventional procedures since the early 1990s at Saint Elisabeth Hospital in Tilburg, the Netherlands. "The clinical credibility of any procedure relies not only on the initial trials that may sanction its use on patients, but also - and perhaps equally as important - on those long-term follow-up studies that prove the procedure's success over time. This study achieves one such milestone."
A retrospective analysis, the study includes 154 consecutive patients who underwent coiling over an 11-year period (January 1995 - August 2006) on aneurysms on the tip of the basilar artery, located in front of the brain stem. Comprising approximately 8.4 percent of all brain aneurysms in the general population, basilar tip aneurysms pose particular difficulties as their position deep in the brain makes a traditional, open neurosurgical approach more dangerous for the patient. Coiling, achieved by placing a mesh of platinum wires in the aneurysm (described as a "bulge" in an artery wall), prevents the aneurysm from rupturing, a serious and often life-threatening condition.
Of the 154 patients undergoing the procedure, 114 (or 74 percent) of the aneurysms had ruptured and 40 (or 26 percent) had not. Following treatment, 144 surviving patients received clinical follow-up up to 144 months, adding up to a total of 637 patient years. Angiographic follow-up (actually viewing the site of the aneurysm using X-ray and MRI technology) conducted on 138 patients up to 122 months revealed that 27 aneurysms (17.5 percent) re-opened over time; these patients underwent additional coiling. Of this number, 11 aneurysms repeatedly re-opened and were coiled up to a total of six times. Re- bleeding occurred in only two patients, indicating an overall annual risk of 0.3 percent for re-bleeding after treatment. In all cases, aneurysm size greater than 10 mm was the only significant predictor for re-treatment at follow-up.
As these results underscore the effectiveness of coiling as a treatment option that ensures success over time, Peluso says the study also shows that in some cases coiling can be considered a staged treatment. "Our strict clinical and angiographic follow-up strategy with additional treatment when necessary was effective in preventing recurrent hemorrhage in ruptured aneurysms, or primary hemorrhage in unruptured aneurysms."
Coiling is performed by physicians specially trained to treat conditions in the brain through endovascular (or "through the artery") and minimally invasive means. Coiling and other treatments are achieved by working through a catheter or narrow tube that is inserted into the groin and threaded up through the arteries directly to the problem site in the brain.
Approximately 2 million people in the United States have an unruptured aneurysm. It is estimated that approximately 30,000 Americans suffer from subarachnoid hemorrhage each year.