Binasal Visual Field Defects Caused by Temporal Posterior Subcapsular Cataracts

The first structures of the eye that light passes through are the refracting components; the cornea and lens. Therefore, it is possible, although not common, to have a visual field defect secondary to a corneal or lens opacity. Understanding where visual information reverses is crucial to attributing the defect to an anterior structure. Since the nodal point of the eye is at the posterior lens/anterior vitreous, an opacity anterior to this will cause an ipsilateral defect whereas it will be reversed at the nodal point. Although cataracts do not typically cause a visual field defect, there have been several case reports of defects secondary to posterior subcapsular cataracts (PSC) that resolve after surgery. We report a case supporting this finding.