Positional misalignment prevention tool and needleless syringe

Abstract

This positional misalignment prevention tool for inhibiting misalignment between a target region of an eyeball into which a substance is to be injected and a syringe for injecting a substance to be injected from an injection part port into the target region comprises: a base body that is disposed around an axis following the direction of injection of the substance to be injected, such that the base body surrounds the periphery of an injection part; and an uneven part that is provided to the target-region side of the base body.