Recent developments in pseudophakic dysphotopsia

Purpose of review: Photic phenomena associated with intraocular lenses can degrade visual performance following intraocular lens implantation. Postoperative dysphotopsia introduces glare, halos, starbursts and shadows in a small number of patients. Understanding the optical mechanisms behind the introduction of these artifacts can lead to improved lens design and a reduction in the deleterious effects of stray light. This review looks at the improvement efforts of recent years to illustrate the systematic hunt for lens problems. Recent findings: Improvements in edge designs have diminished the effects of positive dysphotopsia. However, negative dysphotopsia remains poorly understood and a variety of lens designs and materials can cause negative dysphotopsia. In other efforts, a testing procedure has been developed to improve understanding of the visual percept of a patient suffering dysphotopsia. This test should enlighten practitioners to the deficits their patients face and provide clues to the root causes of the problems. Summary: Intraocular lenses can introduce stray light artifacts into the eye. These artifacts manifest themselves as glare, halos, starbursts and shadows. While positive dysphotopsia (glare, halos and starbursts) has been largely attributed to edge effects of the implant, negative dysphotopsia remains somewhat mysterious and appears to be more related to the patient's anatomical structure than to specific lens designs or materials.