Cone Dystrophy, Nyctalopia, and Supernormal Rod Responses

Phenotypic Characteristics Including In Vivo Cone Photoreceptor Mosaic inKCNV2-Related “Cone Dystrophy with Supernormal Rod Electroretinogram”

“…''C one dystrophy with supernormal rod electroretinogram'' (CDSR) is an autosomal recessive disorder first described by Gouras et al in 1983. 1 Affected individuals usually present within the first two decades of life with symptoms of diminution of distant vision and photophobia; a history of nyctalopia is present in about 50% of cases. [2][3][4][5] Nystagmus is observed in a subset of cases, but is more common in children.…”

Functional Analysis of Missense Mutations in Kv8.2 Causing Cone Dystrophy with Supernormal Rod Electroretinogram

“…Scotopic and photopic responses are reduced and delayed, indicating impairment of rod and cone photoreceptor pathways, respectively. However, at higher light intensities, scotopic b-wave responses are supernormal in amplitude (1). CDSRE presents a recessive mode of inheritance and was recently shown to arise from mutations in KCNV2, the gene encoding a voltage-gated K ϩ (Kv) channel ␣-subunit, Kv8.2 (2).…”

Electroretinogram in Hereditary Retinal Disorders

“…Cone dystrophy with supernormal rod electroretinogram was first described in 1983 (Gouras et al, 1983). This autosomal recessively inherited retinal dystrophy is characterized by reduced visual acuity, abnormal color vision, discrete macular changes, and specific alterations of ERG responses.…”