Finite element optimization of a magnetic anchor traction system for colonic ESD

Endoscopic submucosal dissection (ESD) is a minimally invasive technique for early gastrointestinal neoplasms, yet remains technically challenging with procedure-related risks. A computational modeling framework is developed to numerically investigate ESD traction-force requirements and associated magnetic field characteristics. Based on derived force-distance constraints, an external magnet geometry is designed and evaluated using finite element simulations. The numerical results indicate that the proposed magnet configuration produces a smoother traction force-distance relationship over the prescribed working range, with reduced sensitivity to positional variation. These findings suggest that magnet-geometry optimization may provide a numerical pathway toward more predictable traction-force regulation in ESD.