Hereditary ocular fundus disease is an important cause of irreversible damage to patients' visual acuity. It has attracted much attention due to its poor prognosis and lack of effective clinical interventions. With the discovery of a large number of hereditary ocular fundus genes and the development of gene editing technology and stem cell technology, gene and stem cell therapy emerged as the new hope for curing such diseases. Gene therapy is more directed at early hereditary ocular fundus diseases, using wild-type gene fragments to replace mutant genes to maintain existing retinal cell viability. Stem cell therapy is more targeted at advanced hereditary ocular fundus diseases, replacing and filling the disabled retinal cell with healthy stem cells. Although gene and stem cell therapy still face many problems such as gene off-target, differentiation efficiency, cell migration and long-term efficacy, the results obtained in preclinical and clinical trials should not be underestimated. With the emergence of various new technologies and new materials, it is bound to further assist gene and stem cell therapy, bringing unlimited opportunities and possibilities for the clinical cure of hereditary ocular fundus diseases.
The macula is a critical anatomical structure for primates to acquire high-resolution spatial and color vision, with macula lesions posing a significant threat to patients' visual function and quality of life. Non-human primate (NHP) are the only mammals with a macular structure that is closest to that of humans, thus offering substantial value in the study of macular diseases. Currently, various methods, including spontaneous occurrence, gene editing, drug-induced, light-induced, and mechanical injury, can be employed to screen and establish NHP models for investigating conditions such as oculocutaneous albinism, achromatopsia, retinitis pigmentosa, age-related macular degeneration, and certain rare ocular syndromes. When constructing NHP models, due consideration should be given to other animal models to facilitate complementary research across different model systems. Additionally, leveraging the advantages of NHP and establishing genetically controlled NHP strains is a goal to strive for to achieve sustainable utilization of these resources in research.
At present, the treatment of hereditary retinopathy depends on gene replacement or editing therapy, and adeno-associated virus (AAV) vector is one of the most widely used gene transfer vectors. There are currently three ways to deliver AAV vector-mediated target genes to the retina. Intravitreal injection of AAV vector is currently the most commonly used delivery route, which can effectively improve the functions of retina disorders such as blinding retinal dystrophy in mice. Moreover, studies on X-linked retinoschisis have been undergoing clinical trials, but intravitreal injection has poor transduction in retinal pigment epithelium (RPE) cell layer and photoreceptor cell (PR) layer. Subretinal injection of AAV vector can deliver the target gene to the local retina, resulting in stronger efficiency of transfection and gene expression in the RPE and PR layers, which has been undergoing in animal and clinical trials, however, the high technical operations are required. In recent years, as a new high-profile delivery route suprachorioidal injection of AAV vector can achieve more extensive transfection of target genes in the retina of rabbits and rats, which is less invasive than intravitreal and subretinal injection, Suprachorioidal injection is an important delivery route for future exploration of AAV vector mediated gene therapy for retinal diseases.
RCBTB1 gene associated hereditary retinopathy is an extremely rare inherited retinal disease (IRD) discovered recently. The mutation of RCBTB1 gene can lead to a variety of IRD clinical phenotypes, such as early retinitis pigmentosa and delayed chorioretinal atrophy. The hereditary mode of RCBTB1 gene associated retinopathy is autosomal recessive. RCBTB1 gene plays an important role in maintaining mitochondrial function and anti-oxidative stress defense mechanism of retinal pigment epithelium cells. In the future, it is necessary to further determine whether there is a genotypic and phenotypic correlation in the age of onset of RCBTB1 gene associated retinopathy or multi-organ involvement, and evaluate the safety and efficacy of Adeno-associated virus-mediated RCBTB1 gene replacement therapy in animal models, to explore the feasibility of gene replacement therapy and stem cell therapy.
High myopia has become a global public health issue, posing a significant threat to visual health. There are still some problems in the process of diagnosis and treatment, including the definition of high myopia and pathological myopia, opportunities and challenges of artificial intelligence in the diagnosis and treatment system, domestic and international collaboration in the field of high myopia, the application of genetic screening in children with myopia and high myopia patients, and the exploration of new treatment methods for high myopia. Nowadays, myopia and high myopia show the characteristics of early onset age and sharp rise in prevalence, and gradually become the main cause of low vision and irreversible blindness in young and middle-aged people. Therefore, it is of great significance to accurately define high myopia and pathological myopia, combine artificial intelligence and other methods for screening and prevention, promote cooperation in different fields, strengthen gene screening for early-onset myopia and adopt new and effective ways to treat it.
Diffuse choroidal retinal atrophy (DCA) is a type of myopic macular disease that presents with yellowish-white atrophic changes at the posterior pole of the eyeball. DCA is an important critical feature in the diagnosis of pathological myopia. Early intervention and treatment of this disease are of great significance in delaying the progression of pathological myopia and reducing the impairment of visual function. Ophthalmic imaging data can be used to diagnose the disease, and color fundus photography is the most simple and intuitive. Choroidal thickness is also a key indicator in the diagnosis of DCA, but the diagnostic critical value of choroidal thickness has not been clearly defined. With the development and popularization of artificial intelligence technology, the analysis of lesion imaging data is more objective and accurate. In the future, it is expected to actively establish a standard quantitative evaluation system for DCA by means of artificial intelligence to achieve early detection, early diagnosis and early treatment of pathological myopia.
ObjectiveTo identify the pathogenic mutation in a patient with Oguchi disease.MethodsA Japanese patient with Oguchi disease was enrolled in this study, and underwent a comprehensive medical history assessment and multiple ophthalmic examinations, including BCVA, OCT, color fundus photography and full field electroretinogram. Genomic deoxyribonucleic acid (DNA) was extracted from peripheral blood samples for whole exome sequencing. The gene mutation was detected, and the analysis software was used to determine the conservation of the mutation and the possible structural changes.ResultsThe patient, 71 years old, with consanguineous parents, complained of night blindness since early childhood. BCVA in both eyes was 0.7 and the golden-yellowish reflex appeared in the grey retina. The scotopic 0.01 ERGs showed a extinguished reaction in both eyes. The scotopic 3.0 ERGs showed a “negative” configuration with a significantly reduced a wave and a nearly absent b wave. A homozygous deletion mutation in the SAG gene (c.924delA, p.N309Tfs*12) in this patient was founded by DNA sequencing, which was predicted to generate prematurely truncated SAG protein and result in severe structural change. Homology analysis of the protein sequence indicated that the mutation resulted in an altered amino acid which was evolutionarily highly conserved among different species, strongly suggesting the potential pathogenicity of this homozygous mutation.ConclusionThe mutation c.924delA(309Tfs*12) in SAG cause Oguchi disease in this patient.
ObjectiveTo observe the interobserver agreement of classification of macular degeneration in severe pathological myopia (PM) by ophthalmologists with different clinical experience. MethodsA retrospective study. From January 2019 to December 2021, 171 eyes of 102 patients with severe PM macular degeneration who were examined at Eye Center of Beijing Tongren Hospital of Capital Medical University were included in the study. The clinical data such as age, gender, axial length, spherical equivalent power, fundus color photography, and optical coherence tomography (OCT) were collected in detail. Six independent ophthalmologists (A, B, C, D, E, F) classified each fundus photography based on META-PM and ATN classification of atrophy (A) system and interobserver agreement was assessed by Kappa statistics. According to the classification standard of traction (T) in the ATN classification, the OCT images were interpreted and classified, in which T0 was subdivided into retinal pigment epithelium (RPE) and choroidal thinning, choroidal neovascularization (CNV) with partial RPE and choroidal atrophy, RPE, and choroidal atrophy. Lamellar macular hole can't be classified by ATN system, which was defined as TX. Kappa (κ) test was used to analyze the consistency of classification results between physicians A, B, C, D, E and F. κ value ≤0.4 indicates low consistency, 0.4＜κ value ≤ 0.6 indicates moderate consistency, and κ value ＞0.6 indicates strong consistency. ResultsAmong the 171 eyes of 102 cases, there were 20 males with 37 eyes (19.6%, 20/102), and 82 females with 134 eyes (80.4%, 82/102); age was 61.97±8.78 years; axial length was (30.87±1.93) mm; equivalent spherical power was (－16.56±7.00) D. Atrophy (A) classification results in META-PM classification and ATN classification, the consistency of physician A, B, C, D, E and physician F were 73.01%, 77.19%, 81.28%, 81.28%, 88.89%; κ value were 0.472, 0.538, 0.608, 0.610, 0.753, respectively. In the ATN classification, the T0, T1, T2, T3, T4, and T5 were in 109, 18, 11, 12, 9, and 8 eyes, respectively; TX was in 4 eyes. ConclusionsThere are differences in the consistency of classification of severe PM macular lesions among physicians with different clinical experience, and the consistency will gradually improve with the accumulation of clinical experience.
ObjectiveTo systematically evaluate the effect of pars plana vitrectomy (PPV) combined total peeling of internal limiting membrane (ILM) versus fovea-sparing peeling of ILM for myopic foveoschisis. MethodsA evidence-based medicine study. Chinese and English as search terms for myopic foveoschisis, vitrectomy, and peeling of internal limiting membrane were used to search literature in China National Knowledge Infrastructure, Wanfang database, VIP database, PubMed of National Library of Medicine, Medline, Embase, and Cochrane Library. The high myopic macular schisis was selected as the research object, the intervention method was PPV combined with complete ILM peeling and combined with foveal preservation ILM peeling surgery clinical control study between Jan 1, 2010, and Jun 31, 2021. Incomplete or irrelevant literature and review literature were excluded. The method of Newcastle-Ottawa Scale system was used to evaluate the included literature. The literature was meta-analyzed by RevMan5.3 software. The mean difference (MD) and a confidence interval (CI) of 95% were used to describe the effect sizes of continuous data, fixed effects model was performed. The data including the best corrected visual acuity (BCVA), central fovea thickness (CFT), and postoperative macular hole (MH) were analyzed. ResultsIn those databases, 232 articles based search stratery were totally retrieved, and 10 articles (417 eyes) were finally included for meta-analysis with 245 eyes for PPV combined total peeling of ILM and 172 eyes for PPV combined fovea-sparing peeling of ILM. Meta-analysis results showed there was no significant difference in BCVA and CFT between the two groups (BCVA: MD=0.05, 95%CI 0.00-0.11; P＞0.05; CFT: MD=－4.79, 95%CI －18.69-9.11, P＞0.05). It was compared with the incidence of MH, the difference was statistically significant (odds ratio=5.70, 95%CI 2.22-14.61, P＜0.05). ConclusionBCVA and CFT could be improved by PPV combined total and fovea-sparing peeling of ILM for myopic foveoschisis; compared with complete ILM peeling, the incidence of MH was lower after foveal-sparing ILM peeling.