The treatment of ocular fundus diseases is of significant issue in the clinic, but there exists large controversy on how to standardize the clinical treatment and how to evaluate the effectiveness of treatment on ocular fundus diseases. Emerging application of evidencebased medicine (EBM) provides us a rigorous and feasible pathway for the clinical treatment of ocular fundus diseases. We can improve the quality of clinical treatment research by exploring high quality randomized control trial (RCT) on the basis of patients with ocular fundus diseases in China; and by making full use of the best clinical evidences at home and abroad according to the EBM methods, which may further improve diagnosis and treatment of common ocular fundus diseases in China.
OCT angiography (OCTA) is a fast, noninvasive and quantifiable new technique, which is especially suitable for long-term follow-up in patients with hereditary retinochoroidal degeneration, such as retinitis pigmentosa, Best vitelliform macular dystrophy, adult onset foveomacular vitelliform dystrophy, doyne honeycomb retinal dystrophy, choroideremia and Stargardt disease. During the follow-up, clinicians can find the subtle signs that explain disease development from the blood flow imaging, quantitatively describe the vascular density, timely detect and treat choroidal neovascularization. It is significant to explore the etiology and monitor the course of these diseases. With the development of more treatments for these diseases, OCTA parameters can also be used as indicators to evaluate and compare different therapeutic effects. In the future, more quantitative indicators of OCTA will be applied to evaluate the course of hereditary retinochoroidal degeneration, and provide valuable basis for early diagnosis and treatment.
ObjectiveTo determine the pathogenic gene mutation in a family with incomplete congenital quiescent night blindness (CSNB) of Schubert-Bornschein type. MethodsA retrospective clinical study. In February 2021, one patient and his parents and elder brother from a Han Chinese incomplete CSNB of Schubert-Bornschein type family diagnosed by clinical and genetic examination at Henan Provincial People's Hospital were included in the study. The patient’s medical history, family history were inquired; best corrected visual acuity (BCVA), color vision, fundus color photography, full-field electroretinogram (ERG), and frequency domain optical coherence tomography (OCT) were examined in detail. Five ml of the subject’s peripheral venous blood was collected and the whole genome DNA was extracted. The genomic DNA of the subject was library constructed, and all-exon probes were polymerized for capture. The suspected pathogenic mutation site was verified by Sanger, and the pathogenicity of the gene mutation site was determined by parallel bioinformatics analysis. ResultsThe BCVA of both eyes of the proband (Ⅱ2) was 0.4; the color vision test could not recognize the red color. Fundus examination showed no obvious abnormalities. The retina thickness in the macular area of both eyes was slightly thinned. ERG examination of the whole field showed that the amplitude of ERG b wave was significantly reduced under the stimulation of binocular dark adaptation 3.0 and showed a negative waveform. The mother of the proband (Ⅰ2) had normal BCVA, color vision, fundus color photography, and frequency domain OCT examination. The full-field ERG examination showed that the amplitude of each eye reaction was slightly reduced, and the amplitude of the dark adaptation shock potential was significantly reduced. Genetic testing showed that the proband (Ⅱ2) had a c.1761dupC hemizygous mutation in exon 14 of the voltage-dependent calcium channel α1F subunit gene (CACNA1F gene). The results of protein sequence homology analysis showed that the site was highly conserved in multiple species; the results of bioinformatics analysis showed that the CACNA1F gene c.1761dupC (pY588fs) subsequently had a frameshift mutation and became a stop at position 10. Codons appear translational termination in the conserved regions of the protein. According to the standards and guidelines of the American College of Medical Genetics and Genomics, the mutation was judged to be a possible pathogenic variant. The mother of the proband (Ⅰ2) was a carrier of this site mutation. The clinical and genetic test results of the father and elder brother of the proband were not abnormal. ConclusionCACNA1F gene c.1761dupC is the pathogenic mutation site of the Schubert-Bornschein type incomplete CSNB family.