Deep corneal stromal opacities with contact lenses.

Two patients with deep corneal stromal opacities occurring after prolonged contact lens wear are described. The opacities were associated with folds or striae in Descemet's membrane which they overlay. Development of the opacities was associated with ocular discomfort, photophobia, reduced vision and a history of prolonged daily wearing times. Although the corneal endothelial cell counts were within the normal range, the count was reduced in the affected eye in the patient with the unilateral deep stromal opacity and there was mild polymegathism of the endothelial cells. It is possible that the long-term effects of subtle endothelial cell changes may cause a keratopathy with later scarring and opacification. Poor oxygen transmissibility, carbon dioxide build-up, or suction effects by the lens may all be aetiological factors. Early recognition and treatment, particularly with a better fitting lens of high oxygen transmissibility is important, as once developed the opacities regress only slowly and may result in permanent visual impairment.