Purpose: To study functional and anatomic characteristics of eyes of Russian children with fetal alcohol syndrome (FAS). Methods: One hundred children aged 10–16 years from Russian orphanages (St. Petersburg) were examined: 50 with verified diagnosis of FAS and 50 healthy children. All children were tested for distance visual acuity (VA) with subjective optimal correction (Sivtsev chart), skiascopy, visual inspection for FAS external ocular features, biomicroscopy, eye alignment using cover test, and indirect ophthalmoscopy. Results: All analyzed parameters were worse in children with FAS compared with controls. Children with FAS showed a higher incidence of amblyopia, hyperopia, astigmatism, and anisometropia. In children with FAS, the incidence of blepharophimosis was 34% (8% in controls), epicanthus 14% (2% in controls), telecanthus 32% (compared to 4% in controls), eyelid ptosis 9% (none in controls), and strabismus 26% (10% in controls). Ophthalmoscopy revealed a tilted optic disc in 5 children with FAS (7%) compared with none in controls. Conclusions: Russian children with FAS have a higher incidence of vision problems and eye pathology that needs to be taken into account and requires ophthalmologist monitoring.

Inherited retinal dystrophies (IRD) include a wide range of genetically and phenotypically heterogeneous diseases that lead to progressive loss of vision. With the development of gene therapy, it has become possible to treat two forms of IRD caused by biallelic mutations in the RPE65 gene: isolated retinitis pigmentosa (IRP) type 20 and Leber's congenital amaurosis (LCA) type 2. These nosologies are included in the list of orphan diseases of the Russian Ministry of Health. The success factor for the use of IRD gene therapy is the early stage of the disease, when the viability of retinal cells is preserved. An interdisciplinary approach to diagnostics makes it possible to timely establish the clinical and genetic variant of IRD and refer the patient to targeted therapy. Therefore, at a joint meeting of the Council of Experts of the North-Western Federal District of the Russian Federation, which included ophthalmologists and medical geneticists, a scheme for managing patients with IRD was accepted, including the stages of clinical and functional ophthalmological examination and molecular genetic testing. In addition, regional centers of expertise for IRD were approved in two federal medical institutions in St. Petersburg, whose task is to optimize the quality of diagnosing patients with IRP and LCA.

Background/Objectives: Cone dystrophy with supernormal rod response (CDSRR) is a rare autosomal recessive retinal disorder characterized by a delayed and markedly decreased photoreceptor response. In this article, we aim to describe the clinical course and associated molecular findings in children with cone dystrophy with supernormal rod response associated with recessive mutations in the KCNV2 gene, which encodes a subunit (Kv8.2) of the voltage-gated potassium channel. Methods: The genetic testing of two patients included the next-generation sequencing of a retinal dystrophy panel and direct Sanger sequencing to confirm KCNV2 gene variants, in addition to an electroretinogram (ERG) and spectral domain optical coherence tomography (SD-OCT). Results: Cone dystrophy with supernormal rod response is associated with identified variants in the KCNV2 gene. The genetic analysis of the first case identified a compound heterozygous mutation in the KCNV2 gene, including a de novo nonsense duplication at cDNA position 1109, which led to the premature termination of the p.Lys371Ter codon in the second extracellular domain of the protein. Two patients showed changes in the full-field electroretinogram, especially in the first case, which demonstrated a close to supernormal total electroretinogram amplitude. This study increased the range of the KCNV2 mutation database, added an unreported de novo substitution pattern to KCNV2 gene variants, and linked it to the evaluated clinical studies. Conclusions: The initial clinical manifestations were varied, but both patients presented with hypermetropia and slight exotropia. The ERG findings are characteristic of KCNV2 mutations, and patients exhibited an increased b-wave latency in DA3.0 ERG (combined rod–cone response).

Choroidal effusion syndrome is a rare idiopathic condition that occurs predominantly in middle-aged man with hyperopia and is characterized by ciliochoroidal detachment (CD), followed by exudative retinal detachment. To present a clinical case of postoperative choroidal detachment in a child with SturgeWeberCrabbe syndrome after microinvasive non-penetrating glaucoma surgery. RESULTS: This article presents the clinical case of postoperative choroidal detachment in a child with SturgeWeberCrabbe syndrome after microinvasive non-penetrating glaucoma surgery. Against the background of the existing anomalies in the development of an optic disc after antiglaucomatous intervention for decompensated glaucoma, after the normalization of IOP, the patient developed choroid detachment with exudative retinal detachment the next day of operation. After conservative therapy involving bed rest and double instillation of mydriatics for 1 month, the situation was completely resolved and his vision was restored to 1.0. DISCUSSION: The atypicality of our clinical case of CD lies in the overly pronounced exudative component. In addition to the classic CD vesicles, we observed high exudative retinal detachment as well as high retinoschisis, which is extremely atypical for classical CD. Considering the characteristics of congenital syndrome, it is necessary to accurately differentiate atypical CCA from the rare choroidal effusion syndrome, which also includes CCA with retinal detachment, but does not present with retinoschisis. Against the background of conservative therapy with bed rest and two instillations of mydriatics for 1 month, the situation was completely resolved, and the patients vision was restored to 1.0. In the treatment of such patients, it is always necessary to consider their individual anatomical features as well as to understand the detailed pathogenesis of the complications that arise before rushing to repeat surgery.

Cone dystrophy with supernormal rod responses (CDSRR) is a rare autosomal recessive hereditary retinal dystrophy caused by biallelic KCNV2 variants. Accurate prevalence data remain limited because current estimates rely on clinically ascertained cases. This study aimed to estimate its population prevalence by integrating curated variant evidence and large-scale population genomics resources. The key methodological feature of this study is a multi-tiered pathogenicity framework combined with estimation of a biologically plausible prevalence range: Known pathogenic variants define conservative estimates, whereas probably pathogenic variants and strong variants of uncertain significance define broader estimates. Allele frequencies were analyzed in 807,162 individuals from the gnomAD database and 144,127 Russian genomes from GDB and EvogenDB. A Bayesian framework was applied to calculate disease prevalence from aggregated carrier frequencies across predefined variant tiers. Conservative estimates based on known pathogenic variants, were 1 in 343,926 globally and 1 in 1,911,347 in Russia. Including broader tiers increased estimates to 1 in 14,620 and 1 in 32,764, respectively. Compared to previous clinically ascertained prevalence of 1 in 865,000, these estimates define a wider biologically plausible prevalence range and are consistent with possible clinical underascertainment. This tier-based approach accounts for uncertainty in variant classification when estimating rare disease prevalence.