Aneurysm treatment calls for mandatory imaging follow-up
Endovascular treatment of aneurysms is less invasive than surgical clipping. But physicians must follow up the treatment for more than the traditional six months for it to be effective, according to a new study.
"The commonly used six-month angiogram is clearly insufficient," said Dr. Jean Raymond, an associate professor of radiology at the University of Montreal. "We suggest a six-month transarterial digital subtraction angiogram and further follow-up by TADSA or other vascular imaging techniques for at least another 36 months."
Physicians at the Centre Hospitalier de L'Universite de Montreal performed selective endosaccular coil occlusion of 501 intracranial aneurysms in 466 patients. During a retrospective analysis of these patients, the researchers had access to both short-term (less than one year) and long-term (more than one year) follow-up results.
Patients in the study were treated by endosaccular coiling with Guglielmi detachable coils. A total of 383 aneurysms in 356 patients were followed up at least once by angiography. Raymond and colleagues assessed short-term follow-up angiograms for 353 aneurysms and long-term follow-up angiograms in 277 aneurysms.
They discovered 128 recurrences at a mean follow-up time of 12.31 months and major recurrences in 79 of the patients after an average follow-up of 16.49 months. Nearly half of all recurrences were detected by six months, and almost all had been diagnosed by 36 months.
The most significant predictors of recurrence included treatment during the acute phase after rupture, large aneurysm size, and wide-neck aneurysms. The study was published in the June issue of Stroke.
The treatment of aneurysms is complex, and the determination on whether to go with an endovascular or traditional surgical approach is not easy. The study results do not point to a dogmatic answer, according to Raymond.
"The goal of endovascular treatment is to improve the outcome immediately, perhaps at the cost of possible future angiographic recurrences," he said. "Conversely, alternative therapeutic methods, such as surgical clipping, may lead to increased immediate complications and morbidity. Each case has to be evaluated individually."
Raymond went on to acknowledge the need to improve long-term efficacy for endovascular treatment, which could be attempted by using newer radioactive coils or "Matrix" or "Hydrocoils." It is equally important to verify the validity of such new tools through testing, however.
"Only a randomized study on 500 patients could show a decrease in recurrence rate or exclude an increase in immediate complication rates," Raymond said. "These new alternatives should be used only in the context of such a randomized study. Otherwise, we will submit patients to increased risks of complications without ever knowing if we improve long-term results."
For more information from the Diagnostic Imaging online archives:
