Delayed Foreshortening and Prolapse of Silk Vista Baby into Superior Cerebellar Artery Aneurysm

Flow diversion (FD) has evolved as a minimally invasive treatment for intracranial aneurysms. The Silk Vista Baby (SVB) can be navigated into small cerebral vessels as it can be deployed through a low profile microcatheter. We report on treating a patient in his 70s with an unruptured fusiform right superior cerebellar artery aneurysm using a SVB. Significant foreshortening of the device was noted during the initial procedure, however the position was satisfactory with good apposition and clearance of the aneurysm neck. A stable position of the SVB on one-day and two-month postprocedural CT-angiography (CTA) was also demonstrated. Subsequently, a 6-month follow-up CTA detected delayed foreshortening and prolapse of the SVB into the aneurysm, for which an additional SVB was placed in a second procedure. There were no complications and the patient remained clinically well. While the intraoperative foreshortening was not unexpected, the delayed postprocedural behavior of proximal foreshortening and subsequent prolapse of the SVB into the aneurysm is not previously described. We would like to share this for awareness in this technical note.