Abstract
Purpose :
The current study investigated the phenotype and longitudinal clinical characteristics of pediatric patients with Schubert-Bornschein congenital stationary night blindness (CSNB).
Methods :
This clinic-based, retrospective cohort study included a total of 68 children with CSNB1 and 62 children with CSNB2. Data were derived from patient histories, presenting symptoms, age at onset, age at diagnosis, visual acuity, cycloplegic refractions, full-field electroretinogram (ffERG), optical coherence tomography (OCT), scanning laser ophthalmoscope (SLO), autofluorescence imaging, and genetic findings.
Results :
CSNB1 mutations were identified in NYX (32 patients, 31families), TRPM1 (13 patients,13 families), GRM6 (21 patients, 19 families) and LRIT (2 patients, 1 family). CSNB2 was linked to CACNA1F mutations (62 patients, 61 families). The mean age at presentation was 1.99, 2.03 years and for receiving a diagnosis by ffERG was 5.49, 5.70 years, with molecular diagnosis at 4.63, 5.28 years in CSNB1 and CSNB2, respectively. Initial symptoms were high myopia for CSNB1 and nystagmus for CSNB2, instead of night blindness. The median visual acuity was superior in CSNB1 (0.30 logMAR) compared to CSNB2 (0.52 logMAR). BCVA improvement was more pronounced in CSNB1 than CSNB2(p＜0.05). Myopia progression ranked from fastest to slowest as NYX(-0.81D/y), CACNA1F(-0.52D/y), GRM6(-0.43D/y) and TRPM1(-0.40D/y). During the two-year follow-up, no significant changes were observed in electroretinogram (ERG) metrics.
Conclusions :
Pediatric CSNB patients, presenting before school age, exhibited strabismus, nystagmus and progressive myopia, but infrequent nyctalopia. The progression of myopia and visual development in children with CSNB varies among different genotypes. Stable and electronegative ffERG results were observed during two-year follow-up.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.