Transient rigid lens-induced striae in keratoconus.

We have observed spontaneous development of striae and an enhanced visibility of them after placing rigid gas permeable contact lenses on six patients suspected of having early keratoconus. These fine folds subside upon removal of the rigid lens. This observation assists clinicians with the differential diagnosis of irregular astigmatism when the definitive biomicroscopic signs of keratoconus are either not present or are so subtle that their presence is questionable. Although these striae may not occur in all patients suspected of having early keratoconus, we find that observation of the posterior cornea in the presence of a rigid lens will often confirm the diagnosis of keratoconus. We have not seen similar striae in patients whose clinical presentation is not consistent with early keratoconus.