Studies of the ocular compatibility of hydrogels. A review of the clinical manifestations of spoilation.

The range and nature of the various clinical manifestations of hydrogel contact lens spoilations are considered. An indication of the present view of the occurrence, chemical composition and potential aetiology for discrete elevated deposits, organic and inorganic surface films, plaques and granular deposits, microbial spoilation, lens discoloration and other extrinsic factors is provided. The literature is principally concerned with the clinical manifestations of spoilation and most observations have been made on lenses that have become so severely spoiled as to be unwearable. No serious attempt has yet been made to identify those tear species responsible for the development of the various types of deposits or of the effects of variations in the bulk and lens chemistry, and also wear protocols on the formation of deposits.