Direct injection of retinal cells into patients’ eyes is a new and improved therapeutic method to address cataracts, but one challenge is that the survival rate of cells during injection is very low. To solve this problem, in this study, the force distribution on retinal cells in injectors with two needle shapes was analysed by coupling the discrete element method with computational fluid dynamics and implementation of an immersed boundary method. Two injectors were considered: one with a straight needle and the other with a curved needle. The velocities of retinal cells in the injector with a straight needle were slightly higher than those in the injector with a curved needle. In addition, injection speed greatly affected the force distribution on retinal cells, with the retinal cells near the piston subjected to the highest forces during injection. The forces on retinal cells strengthened with increases in both retinal cell concentration and piston displacement.
Keywords: Retinal cells, Force distribution, Injection, DEM–CFD, Immersed boundary method,