| Cone dystrophy with supernormal rod response is an inherited retinopathy, with an onset in the first or second decade of life. The disease has characteristics of poor visual acuity (due to central scotoma), photophobia, severe dyschromatopsia and occasionally nystagmus. Night blindness usually develops later in the course of the disease, but it can also be apparent from childhood. A hallmark of the disease is the decreased and delayed dark-adapted response to dim flashes in electroretinographic recordings, which contrasts with the supernormal b-wave response at the highest levels of stimulation. |