Characterising the refractive error in paediatric patients with congenital stationary night blindness: a multicentre study

Abstract

Background/AaimsCongenital stationary night blindness (CSNB) is an inherited retinal disease that is often associated with high myopia and can be caused by pathological variants in multiple genes, most commonlyCACNA1F,NYXandTRPM1. High myopia is associated with retinal degeneration and increased risk for retinal detachment. Slowing the progression of myopia in patients with CSNB would likely be beneficial in reducing risk, but before interventions can be considered, it is important to understand the natural history of myopic progression.MethodsThis multicentre, retrospective study explored CSNB caused by variants inCACNA1F,NYXorTRPM1in patients who had at least 6 measurements of their spherical equivalent of refraction (SER) before the age of 18. A mixed-effect model was used to predict progression of SER overtime and differences between genotypes were evaluated.Results78 individuals were included in this study. All genotypes showed a significant myopic predicted SER at birth (−3.076D, −5.511D and −5.386D) forCACNA1F,NYXandTRPM1respectively. Additionally, significant progression of myopia per year (−0.254D, −0.257D and −0.326D) was observed for all three genotypesCACNA1F,NYXandTRPM1, respectively.ConclusionsPatients with CSNB tend to be myopic from an early age and progress to become more myopic with age. Patients may benefit from long-term myopia slowing treatment in the future and further studies are indicated. Additionally, CSNB should be considered in the differential diagnosis for early-onset myopia.