Silk vista baby flow diversion beyond the circle of Willis: A single-center experience with long-term outcomes

Abstract

Introduction: There is a lack of evidence of flow diversion (FD) safety for aneurysms treatment beyond the circle of Willis. Therefore, we provide a single-center real-world experience with the Silk Vista Baby (SVB).

Methods: A single-center database was retrospectively reviewed for aneurysms treated with SVB flow diverters. Demographic information, clinical presentation, radiographic characteristics, procedural complications, and outcomes were assessed.

Results: About 57 patients (66.7% female, mean age 54.3 ± 13.2) encompassing 57 aneurysms were included. Overall, 40.4% were ruptured: 68.4% saccular, 17.5% blister, 8.7% fusiform, and 5.3% dissecting. The majority were in the anterior circulation (68.4%), and in 48.2% of cases, the distal vessel diameter was inferior to 2 mm. The symptomatic ischemic rate was 5.2%, with one case due to in-stent thrombosis (1.8%). There were no hemorrhagic complications. Complication rates did not differ between ruptured and unruptured lesions (p = 0.356). There were no cases of delayed aneurysm rupture, and overall mortality was 1.8%. The median follow-up time was 18 ± 12 months. In-stent stenosis rate was 10.5% (6/57), all of which were asymptomatic. At the last follow-up, 70.2% of cases had an adequate occlusion (OKM C and D), and 96.5% had an mRS of 0-2.

Conclusion: In our series, SVB was shown to be a safe device in the treatment of not only distal anterior circulation aneurysms but also in the management of complex posterior fossa and ruptured blister aneurysms. Multicenter studies are needed to confirm and generalize these results.

Keywords: Silk vista baby; blister aneurysms; complex aneurysms; distal aneurysms; subarachnoid hemorrhage.

Figure 1.

A 58-year-old patient presented with a partially thrombosed (1A) left posterior inferior cerebellar aneurysm (PICA) causing right hemisensory loss, dysphagia, and left ataxia. Digital subtraction angiography (DSA) shows a partially thrombosed (1A) left posterior inferior cerebellar aneurysm (PICA). 3D DSA reconstruction from the left vertebral artery (1B) and a profile DSA (1C) show a left PICA dissecting fusiform aneurysm. A balloon test occlusion didn't evidence good collateral flow and a flow diverter strategy was then chosen. 1D: non - subtracted DSA showing the deployment of two SVB devices (2.25 × 20 mm and 2.5 × 20 mm) across the entire aneurysm neck. 1E: post-deployment profile angiography. 1F: vaso-CT showing the distal end of the stent in the true vessel lumen, surrounded by the partially thrombosed aneurysm (false lumen). 1G: vaso-CT showing the proximal end of the stent, well apposed to the vessel wall. 1H: 6-month MRI control shows no longer a thrombosed aneurysm compressing the brainstem and the cerebellum. 1I: 6-month DSA 3D reconstruction from the left vertebral artery showing patency and reconstruction of the left PICA.