שאלה משלב א׳ במחלות עיניים · מועד 2024 (May), שאלה 116

A square-edged intraocular lens increases the risk of negative dysphotopsia, because the sharp edge casts a discrete shadow on the peripheral nasal retina which the patient perceives as a dark temporal crescent. Other contributors are a small capsulorrhexis with the edge overlapping the optic, a high-index acrylic material, a small pupil, a short distance from iris to lens and in-the-bag placement; Fuchs dystrophy is unrelated, and a round-edged, lower-index lens or reverse optic capture reduces the problem.

מקור: Kanski p. 11 198