Assessment of conjunctival hyperemia in contact lens wearers. Part II.

A photographic reference scale has been used to grade conjunctival hyperemia in contact lens wearers. A sample of hard lens wearers, included as a control, has been found to have significantly less conjunctival hyperemia (p less than 0.01) than either of two soft lens wearing groups (one using preserved storage solutions and the other using unpreserved storage solutions). Because both soft lens samples were found to have more hyperemia, it is concluded that factors other than storage solution preservative contribute to increase conjunctival hyperemia in soft lens wearers. However, the preserved storage soft lens wearers had significantly more hyperemia than the unpreserved storage solution group (p less than 0.01). The conclusion is that, apart from acute and subacute responses, there may be a relatively benign chronic response to soft lens storage solution that is associated with minimal symptoms.