The year 2002 in therapeutic neuroradiology has been dominated by the publication of the International Subarachnoid Aneurysm Trial(ISAT), which has already generated considerable debate among those who treat cerebral aneurysms. Guaranteed to be controversial, the interim results of ISAT showed a 22.6% relative and a 6% absolute risk reduction of dependency or death for coiling relative to surgery in the treatment of cerebral aneurysms, triggering a premature halt to the trial. The results suggest that in patients with small, ruptured anterior circulation aneurysms who are a good neurologic grade and are candidates for either endovascular coiling or surgery, the incidence of an outcome free of disability at 1 year is higher with coils. Critics have pointed out the large number of anterior circulation aneurysms(97%), the large number of patients who were eligible for the study but were not randomized(7416), the initially limited follow-up, and the small number of participating North American centers, reflecting a known practice bias. The continuing analyses of this data, particularly long-term recanalization rates with coils, promise to be very instructive. Nevertheless, the future of aneurysm surgery may ultimately belong to those who can coil or clip.
   There have been many modifications and advances in coil technology to address the problems of wide-necked aneurysms and recanalization. Coils have been used to deliver beta radiation, bioabsorbable polymers, and gene-delivery vectors to promote thrombosis and cellular response inside aneurysms. Neck bridging devices and balloon and stent-assisted techniques using coils and solid polymers such as Onyx have all been used to successfully manage wide-necked and surgically inaccessible lesions. Three-dimensional angiography is becoming the gold standard for decision making regarding optimal aneurysm treatment.
   It is becoming clear that the complete management of cerebrovascular disease requires practitioners who possess endovascular skills. Ever increasing numbers of vascular neurosurgeons are seeking interventional training, and the growing field of interventional stroke neurology is attracting many young neurologists.
   The American Society of Interventional and Therapeutic Neuroradiology(ASITN) and Japanese Society of Intravascular Neurosurgery have etablished guidelines to ensure that these candidates receive a good grounding in the underlying radiological sciences. The discipline of interventional neuroradiology may become the model of a fruitful collaboration between multiple specialties working together for maximum patient benefit.

REFERENCES

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