Hydrogels for intraocular lenses and other ophthalmic prostheses

The eye is unique among all organs in that it has large volumes which are completely avascular. These avascular tissues are inherently isolated from the normal immune response of the body. This ‘immunological privilege’ makes the eye an excellent candidate for permanent prostheses using hydrogels which mimic the eye’s natural soft, transparent hydrogel materials. Both the lens and vitreous humors are natural hydrogels. They transmit light from the environment to the retina, necessitating transparency. However, their mechanical function requires some elasticity. Understanding the optical and mechanical interplay in these tissues will allow successful permanent prostheses using biomimetic hydrogels. The eye is also a focal point for the investigation of hydrogel-based tissue adhesives. Since many eye surgeries require the surgeon to cut holes in the cornea, a transparent method for sealing the hole will allow continued visual function during rehabilitation. Selecting a suitable adhesive may also allow a more rapid regeneration of surrounding cells and less chance of long-term effects from the surgical procedure.