Dr. Masket has been working with Nicole R. Fram, MD, in studying negative dysphotopsia. He noted that their clinical experience and the bulk of literature reports support the conclusion that this particular visual phenomenon, which involves perception of a dark temporal crescent, can develop with any IOL implanted in the capsular bag with the anterior capsulotomy overlying the optic edge.
The etiology is mediated, in part by the presence of an interface between the front surface of the IOL and the anterior capsulotomy. IOL material does not appear to be a risk factor.
“In a study that is in press, we reviewed 40 eyes that underwent secondary surgery for management of chronic negative dysphotopsia,” Dr. Masket said. “We found that about 75% of the eyes had an acrylic IOL and the remaining eyes had a silicone lens. That distribution roughly matches the market shares of implanted IOLs.”