Clinical evaluation of the Tangent Streak trifocal contact lens

Abstract

The Tangent Streak trifocal is a rigid gas permeable contact lens with horizontal segments for distance, intermediate, and near correction. We undertook a prospective clinical evaluation of the Tangent Streak trifocal to determine the efficacy of this lens in correcting presbyopic symptoms. Distance, intermediate, and near corrections were compared using visual acuity and contrast sensitivity charts in 25 presbyopic ametropes. Compared to the original bifocal correction, the Tangent Streak trifocal provided 21 of 25 of study patients (84%) with subjectively improved intermediate vision, while maintaining distance and near vision. Twelve of 16 dissatisified bifocal contact lens wearers (75%) were successfully fit with the Tangent Streak trifocal. This study shows that the Tangent Streak trifocal lens can effectively provide multifocal vision to presbyopic ametropes.