Medical Student David Geffen School of Medicine at UCLA Los Angeles, California, United States
Introduction: Flow diverting stents (FDS) placed in the mobile cervical internal carotid artery (cICA) are subject to post-operative migration and proximal intimal hyperplasia. These complications are thought to arise from incomplete wall apposition of the proximal FDS secondary to physiologic vessel motion. We report mid-term angiographic follow-up of a novel proximal anchoring technique using laser cut nitinol stents to secure the proximal FDS against the vessel wall and therefore avoid such complications.
Methods: A prospectively maintained IRB-approved institutional database of the senior authors was retrospectively reviewed to identify petrocervical ICA segment dissections treated with FDS and a proximal anchoring stent. Pertinent demographics, procedural details, and outcomes were analyzed.
Results: Between December 2019 to January 2022, 9 complex ICA dissections were successfully treated with Surpass Streamline FDS implantation in the mobile cICA, with six cases associated with pseudoaneurysm formation. Fifty-six percent (n=5) were female. Between 2-4 FDS were implanted per case along with a proximal anchor laser-cut nitinol carotid stent (diameter range 6-8mm, length range 30-60mm). No perioperative ischemic or hemorrhagic complications were noted, nor stent migration. Six of the 9 (67%) cases have at least 6-month follow-up angiography (mean 8.9 +/- 1.5 months; range 6-15 months) with complete resolution of the dissection in all 6 cases (100% Raymond grade 1). One case of in-stent stenosis occurred at 6-months and resolved at 12-month follow-up. Three of 6 cases with follow-up still require 12-month follow-up angiography.
Conclusion : In a small cohort, mid-term angiographic follow-up of FDS treatment for complex petrocervical ICA dissections with adjunctive proximal anchoring using a laser-cut nitinol carotid stent yielded complete resolution of dissection in available follow-up without clinically significant complication. The described proximal anchoring technique may provide additional protection from stent migration and intimal hyperplasia attributed to patient neck movement and complete resolution of the dissection.
