Abstract

Unruptured intracranial aneurysms (UIA) are increasingly treated with endovascular treatment although this method continues to be associated with aneurysm recurrences in up to 30–40%, especially for large aneurysms or those with wide (>4 mm) necks. Although the significance of a recurrence remains unknown, they not only require angiographic follow-up but discovery sometimes leads to retreatment, with associated risks. Several strategies have been developed to decrease recurrence rates, including the addition of an endovascular stent to standard coiling. Stents may permit more complete coil occlusion, form a neointimal scaffold at the aneurysm neck and normalize blood flows. A randomized study of endovascular treatment of UIAs for aneurysms treated with or without stenting has not been performed. The design of the STenting in Aneurysm Treatments (STAT) trial is reported, which compares angiographic and clinical outcomes following endovascular treatment of UIAs with or without stents. The first phase of this pragmatic management trial will examine angiographic outcomes, in order to determine whether the addition of a stent to standard coiling can decrease recurrence rates, while the second phase of the study will determine if stenting is associated with increased patient morbidity and mortality. The STAT trial collaborators intend to enroll 600 patients, a size sufficient (at 80% power and 0.05 significance) to detect a decrease in recurrences from 33% to 20% by 1 year, and to verify that stenting does not result in an increase in the proportion of patients experiencing neurological disability (modified Rankin Scale score >2), from 6% to 12%.