What we have learnt from 30 years living with positive dysphotopsia after intraocular lens implantation?: a review

Introduction: Positive dysphotopsia (PD) is a topic of great interest in intraocular lens (IOL) field. Several approaches have been developed from the physics, psychophysics and psychometry fields to measure PD. However, the complexity of characterizing this phenomenon and the lack of standardization have resulted in a considerable bias between studies that avoid its inclusion in systematic reviews and meta-analysis. Areas Covered: The purposes of this review were first to suggest a definition and classification of PD that minimize the bias between studies that use different questions to rate PD prevalence. Second, to describe the limitations found in psychophysical studies. Finally, to identify the associations between photic phenomena (PP) and the design of monofocal and multifocal IOLs. A non-systematic literature review was conducted from the last 30 years. Expert Opinion: PD can be defined as any bothering bright artifact perceived by patients along or around direct bright lights or reflected over objects located in the visual field. If the patient is not bothered by the artifact, the term PP should be used instead. Psychophysical approaches measure PP and not PD. Whereas LED approaches are preferable, these really measure Light Disturbance because the classification of PP cannot be differentiated.