Multi-objective RVEA optimization of a closed-cell segmented stent retriever for balancing biomechanical forces.

Abstract

Mechanical thrombectomy for acute ischemic stroke (AIS) faces significant challenges in complex vascular geometries, where existing stent retrievers often struggle to capture thrombus effectively. This study introduces an enhanced closed-cell segmented flexible (ECSF) stent retriever designed to address these challenges and improve thrombus capture, particularly in intricate vascular environments. Fabricated from superelastic Nitinol, the ECSF stent underwent a multi-objective optimization process using the RVEA algorithm to balance key performance metrics, including radial resistive force, hoop force, chronic outward force, and volume, while ensuring the strain remained within Nitinol's superelastic limit. Finite element analysis demonstrated the ECSF stent's superior mechanical performance compared to a commercial stent. In vitro experiments further validated its effectiveness in capturing and removing thrombus in complex vessel conditions, highlighting its potential as a promising solution for AIS treatment, even under suboptimal deployment conditions.