Fig. 1 A. Slit lamp light is focused on the retina using the widest possible slit that fits within margins of the macular cyst or hole. B. Appearances of slit beam when focused on macular cyst or hole of patient. (Margherio R, Trese MT, Margherio A, et al: Surgical management of vitreomacular traction syndromes. Ophthalmology 96:1437, 1989)