Congenital stationary night blindness (CSNB) is an inherited retinal disease (IRD) that causes night blindness in childhood with heterogeneous genetic, electrophysical, and clinical characteristics. The development of sequencing technologies and gene therapy have increased the ease and urgency of diagnosing IRDs. This study describes seven Taiwanese patients from six unrelated families examined at a tertiary referral center, diagnosed with CSNB, and confirmed by genetic testing. Complete ophthalmic exams included best corrected visual acuity, retinal imaging, and an electroretinogram. The effects of identified novel variants were predicted using clinical details, protein prediction tools, and conservation scores. One patient had an autosomal dominant CSNB with a RHO variant; five patients had complete CSNB with variants in GRM6, TRPM1, and NYX; and one patient had incomplete CSNB with variants in CACNA1F. The patients had Riggs and Schubert–Bornschein types of CSNB with autosomal dominant, autosomal recessive, and X-linked inheritance patterns. This is the first report of CSNB patients in Taiwan with confirmed genetic testing, providing novel perspectives on molecular etiology and genotype–phenotype correlation of CSNB. Particularly, variants in TRPM1, NYX, and CACNA1F in our patient cohort have not previously been described, although their clinical significance needs further study. Additional study is needed for the genotype–phenotype correlation of different mutations causing CSNB. In addition to genetic etiology, the future of gene therapy for CSNB patients is reviewed and discussed.

There has been limited research regarding the status of foveal hypoplasia and the characteristics of the optical components of the eye in patients with familial exudative vitreoretinopathy (FEVR) and retinopathy of prematurity (ROP). In this retrospective cohort study, patients were classified into five groups: patients with stage 1 and 2 FEVR (FEVR group), patients with ROP who received treatment (treated ROP group), patients with ROP who did not receive treatment (untreated ROP group), patients without ROP who had been born preterm (preterm group), and healthy patients who had been born at term (full-term group). Visual acuity, refractive error, characteristics of the optical components, and features of the fovea were compared. In total, 179 eyes from 100 patients were included. Patients in the FEVR group had the highest degrees of myopia (p < 0.001). The axial length of patients in the FEVR group was significantly longer than that of patients in the treated and untreated ROP, preterm, and full-term groups (p < 0.001, p < 0.001, p = 0.001, and p = 0.003, respectively). Patients in the FEVR group had a higher proportion of grade 4 foveal hypoplasia and thinner foveae than those in the other groups (p < 0.001). Patients with FEVR had significantly greater myopic change than patients with ROP; the significantly longer axial length of the FEVR group might be the reason for the greater myopic change and lesser macular thickness. Patients in the FEVR group had more foveal hypoplasia than those in the other groups.

Purpose To compare the manifestations of photoreceptors (PRs) in three hereditary optic neuropathies affected by primary mitochondrial dysfunction and discuss whether the retinal ganglion cells (RGCs) or the PRs are preferentially affected. Methods A retrospective analysis of patients with genetically confirmed diagnoses of optic neuropathies associated with mitochondrial dysfunction was performed. This cohort included Leber's hereditary optic neuropathy (LHON), autosomal dominant optic atrophy type 1 (OPA1), and optic atrophy type 13 (OPA13). Patient chart evaluations included clinical characteristics, best-corrected visual acuity (BCVA), fundus photography, spectral-domain optical coherence tomography (SD-OCT), electroretinogram (ERG), and visual evoked potential data. Results This analysis included seven patients with LHON, six with OPA1, and one with OPA13 from a tertiary medical center. Thirteen of the 14 individuals were male. The average BCVA at diagnosis was 20/285 and 20/500 in the right and left eyes, respectively. Five of the seven patients with LHON, and three of the six patients with OPA1 also showed a mild amplitude reduction or delayed latency on light-adapted ERG and 30-Hz flicker responses; however, SD-OCT imaging did not show correlated PR abnormalities. Notably, a 7-year follow-up of a patient with OPA13 revealed degeneration of RGCs prior to the degeneration of PRs. Follow-up data also demonstrated continuous loss of cone outer segment tips on SD-OCT imaging. Conclusions RGCs are, in general, affected by mitochondrial dysfunction, whereas variable PR dysfunction exists in patients with LHON and OPA1, especially with respect to the cone responses. Involvement of PRs is particularly evident in OPA13 after RGC degenerations.