KIZ and retinitis pigmentosa 1: Prior reports of KIZ-related RP also describe patients who developed nyctalopia in their late teens and undetectable ERG responses by age 35, while others retain visual acuity of 20/20–20/40 by age 50, decreased central retinal sensitivity with visual field constriction, preserved islands of perception peripherally and foveal outer retinal preservation [18].