@article {1354342, title = {Effect of retinopathy of prematurity on scotopic spatial summation}, journal = {Invest Ophthalmol Vis Sci}, volume = {55}, number = {5}, year = {2014}, month = {2014 Apr 29}, pages = {3311-3}, abstract = {PURPOSE: To evaluate scotopic retinal organization in retinopathy of prematurity (ROP) through a study of spatial summation. METHODS: Thresholds for a range of stimulus diameters (0.4{\textdegree}-10{\textdegree}) were measured using a two alternative, spatial, forced choice psychophysical procedure. The critical diameter (DCRIT) for complete summation was estimated in subjects with a history of severe ROP (N = 7) and mild ROP (N = 17). Subjects who were born preterm and never had ROP (N = 16) and term-born subjects (N = 7) were also tested. The subjects ranged in age from 9 to 17 (median 13.5) years. RESULTS: Critical diameter for complete spatial summation was significantly larger in ROP subjects than in subjects who never had ROP and in term-born control subjects. Critical diameter varied significantly with severity of ROP. CONCLUSIONS: The larger DCRIT values in ROP are consistent with altered organization of the post receptor retina. This may offer the ROP retina a strategy for achieving noise reduction and good dark-adapted visual sensitivity.}, keywords = {Adolescent, Child, Dark Adaptation, Female, Humans, Male, Photic Stimulation, Psychophysics, Retinal Rod Photoreceptor Cells, Retinopathy of Prematurity, Sensory Thresholds, Visual Perception}, issn = {1552-5783}, doi = {10.1167/iovs.14-14344}, author = {Hansen, Ronald M and Tavormina, Jena L and Moskowitz, Anne and Fulton, Anne B} }