Effect of Minimizing Light Exposure Intensity on Macular Function After Cataract Surgery in Patients With Early or Intermediate AMD

Overview

Cataract surgery is one of the most frequently performed surgical interventions worldwide. The microscope light-induced retinal toxicity after cataract surgery has been described in several reports even in short procedures; however, this potential toxicity has not been evaluated by objective criteria. Indeed, this retinal phototoxicity would be increased for patients with mild macular diseases such as early stages of AMD (Aged Macular Degeneration) (ie: drusen) which are frequently associated in elderly patients with cataract. The aim of the study will be to assess the potential functional macular effects by focal and multifocal ERG after cataract surgery with NGenuity by comparison to Standard Operating Microscope (SOM). This study would particularly address eyes at risk for macular toxicity like patients with early or intermediate AMD

Cataract surgery is one of the most frequently performed surgical interventions worldwide. The development of phacoemulsification technology, instrumentation and surgical techniques has improved both the efficacy and safety of procedures, reducing rates of serious postoperative adverse events. The microscope light-induced retinal toxicity after cataract surgery has been described in several reports even in short procedures; however, this potential toxicity has not been evaluated by objective criteria. Indeed, this retinal phototoxicity would be increased for patients with mild macular diseases such as early stages of AMD (Aged Macular Degeneration) (ie: drusen) which are frequently associated in elderly patients with cataract. A systematic literature review of 129 664 individuals estimated the prevalence of early macular degeneration to 8.01% in population aged 45 to 85 years. A three-dimensional (3D) heads-up system (NGenuity®, Alcon, Fort Worth, TX) was recently introduced for both vitreoretinal and cataract surgery, radically improving the quality of surgical visualization. This system allows performing cataract surgery at a lower fraction of light intensity reducing patient's photophobia complaints during surgery and probably preventing potential phototoxic macular injury in cataract surgery. In a recent pilot study, the Ngenuity system was reported to decrease significantly the operative light intensity and to contribute to a faster visual recovery relative to traditional microscopes in series of 35 patients (51 eyes) who underwent cataract surgery. The aim of the study will be to assess the potential functional macular effects by focal and multifocal ERG after cataract surgery with NGenuity by comparison to Standard Operating Microscope (SOM). This study would particularly address eyes at risk for macular toxicity like patients : * with early AMD: medium-sized drusen (between 63µm and 125µm in diameter) without pigmentary abnormalities * with intermediate AMD : large drusen (\>125 µm) or pigmentary abnormalities in the retina associated with at least medium drusen