Simulation-Driven Design and Morphological Characterization of an Artificial Lymphatic Vessel

Secondary lymphedema is a persistent complication resulting from damage to the lymphatic system, including lymphatic vessel and lymph-node injury after cancer treatment. The authors previously proposed a lymphatic vessel concept, followed by fabrication of a first-generation (V1) prototype in 2024. The present study advances this work through simulation-driven redesign leading to a second-generation (V2) prototype and morphological characterization. Computational fluid dynamics (CFD) was used to reassess the initial flow boundary condition and evaluate valve openings. Assigning 4 L/day to a single micrometric vessel produced unrealistically high local velocities and pressure losses, prompting reassessment. Subsequent simulations adopted an inlet ve-locity of 0.0013 m/s and evaluated 60 and 120 µm valve openings, while 3 and 6 µm configurations were retained as narrow reference geometries. Larger openings produced substantially lower maximum velocities and pressure drops. The resulting V2 prototype has a nominal length of 3.32 mm, outer diameter of 150 µm, inner diameter of 140 µm, and approximately 5 µm wall thickness. Scanning electron microscopy (SEM) characterized the fabricated V2 structure at 23×–1500× magnification, confirming the tubular architecture and local measurements of lumen diameter and wall thickness. These findings support engineering development and identify parameters requiring experimental validation before biological or clinical assessment.