Congenital stationary night blindess-2 (incomplete congenital stationary night blindness (iCSNB) or CSNB-2) is a nonprogressive, X-linked retinal disease which can lead to clinical symptoms such as myopia, hyperopia, nystagmus, strabismus, decreased visual acuity, and impaired scotopic vision.
She also had a constant exotropia, so we examined the PHOX2B gene associated with both schizophrenia and strabismus, and detected a 5-alanine deletion.
Children with TRPM1-associated cCSNB presented before school age with progressive myopia as well as strabismus and nystagmus (but not nyctalopia), with stable, electronegative ffERG results, mildly subnormal full-field stimulus threshold testing results, and a constricted I2e isopter on perimetry.
Patients with fukutin-related protein gene mutation tend to have no or mild eye involvement (generally strabismus), with very few cases reported of moderate to severe eye involvement.