Foreign-body reaction against intraocular lenses.

We studied five intraocular lens implants removed for various reasons by light, transmission, and scanning electron microscopy. Four implants were Binkhorst four-loop lenses; the fifth was of an unidentified type. The durations of implantation ranged from three to 36 months, with an average of 14 months. The surface of all implants was covered with a thin acellular membrane of unknown nature. On top of this membrane we found different types of cells that are normally involved in a foreign-body reaction. These included fibroblasts, histiocytes, epithelioid cells, and multinucleated foreign-body giant cells, in all stages. Our findings suggested that iris-fixed artificial lenses are subject to a defensive cellular reaction by the host. The limited extent of this reaction was correlated with the success of the implant.