Here, a novel ring-implanted poly vinyl alcohol (PVA) contact lens (CL) is fabricated and evaluated as a therapeutic CL with potential of sustained release of hyaluronic acid (HA). HA is loaded on chitosan (CS) nanoparticles (NPs) and then the HA-loaded NPs are dispersed in a ring shape PVA hydrogel which is implanted in the final PVA CL. (284)