Does stent type impact coil embolization outcomes in extended follow-up of small-sized aneurysms (< 10 mm)?

PURPOSE: Self-expandable stents have enabled endovascular treatment of wide-necked aneurysms (ordinarily viewed as technically prohibitive), with favorable outcomes. However, the impact of stent type on occlusive stability has not been adequately investigated. In small-sized unruptured saccular aneurysms, we generated estimates of stent-assisted coil embolization outcomes during follow-up monitoring. Stent type and other risk factors linked to recanalization were analyzed.

METHODS: A cohort of 286 patients harboring 312 small-sized unruptured aneurysms (< 10 mm) was subjected to mid-term and extended follow-up monitoring after stent-assisted coiling. Three types of stents (Enterprise, 192; Neuroform, 27; LVIS, 93) were deployed in this population; all medical records and radiologic data of which were reviewed. Mid-term recanalization rates and related risk factors were assessed using binary logistic regression analysis.

RESULTS: A total of 49 aneurysms (15.7%) displayed recanalization at 6 months postembolization, with 34 and 15 instances of minor and major recanalization, respectively. Multivariate analysis indicated that wide-necked aneurysms (> 4 mm) (HR = 2.362; p = 0.017), incomplete occlusion at time of coiling (HR = 2.949; p = 0.002), and stent type (p = 0.048) were significant factors in mid-term recanalization, whereas hypertension (p = 0.095) and packing density ≤ 30% (p = 0.213) fell short of statistical significance. Compared with Enterprise (HR = 2.828) or Neuroform (HR = 4.206) stents, outcomes proved more favorable with use of LVIS.

CONCLUSIONS: Above findings demonstrate that in addition to occlusive status at time of coil embolization and neck size, stent type may affect follow-up outcomes of stent-assisted coil embolization in small-sized aneurysms. LVIS (vs Enterprise or Neuroform stents) performed best during follow-up monitoring in terms of limiting recanalization.