Multicenter randomized controlled studies can recruit more subjects in a relatively short period of time, avoiding the bias of single research institution studies, resulting in reliable conclusions and providing strong guidance to clinical practice. They are the most scientific and most reliable methods to evaluate clinical researches. However, there are few multicenter clinical trials in China as Chinese doctors are often trapped in difficulties in clinical research, including imperfect research system, lack of experience, capital investment deficient, the tension in the doctor-patient relationship and so on. Although the above problems are related to medical system architecture of our country in a certain extent, compared with the overseas, we also have our own advantages, such as resource of our patients, doctors, and diseases type. Pay attention to discovering of new type of diseases, looking for genetics discipline, and exploring new medical technology is an important task of clinical research. We have plenty of high level ophthalmology centers at present, which provide favorable conditions for launching multi-center clinical trial studies. We have good reasons to believe that, if we can effectively exploit the resources in our hands, carefully observe and discover clinical problems, there will be more convincing clinical results present in the world after bring up hypothesis boldly while prove it conscientiously and carefully.
The classical surgical operations for foveoschisis in high myopia are vitrectomy, artificial posterior vitreous detachment, removal of the pre-macular vitreous cortex, removal of the inner limiting membrane (ILM) and intraocular gas tamponade, with some minor variations on those basis, including no removal of the ILM or ILM peeling with preservation of the fovea area; with or without gas filling, long-term silicone oil tamponade, etc. All the procedures have achieved certain efficacy and the foveoschis can be fully or partially relieved and the visual acuity can be improved to different degrees. It is worthwhile to emphasize, the most common and serious complication of the surgery is the occurrence of full-thickness macular hole or even postoperative macular hole retinal detachment. To address the risk of such complications, a safe and effective outcome can be achieved in the majority of cases by using ILM peeling with preservation of the fovea area. For high-risk cases where the operator is concerned about intraoperative or postoperative macular hole, a long-term silicone oil tamponade without ILM removal is proposed to prevent the risk of surgery-related macular hole formation.
Central serous chorioretinopathy (CSC) is a common macular disease, mainly manifested as a plasma detachment of the macula. Photodynamic therapy (PDT) is an effective treatment for CSC, but with the shortage of the photosensitizer Verteporfin, the effective treatment of CSC has become a common concern for ophthalmologists. In this paper, based on the latest research results on the relationship between the changes in the thickness of the outer nuclear layer and the natural course of the disease and PDT therapy, we propose that patients with CSC should receive effective treatment as early as possible to prevent irreversible damage to visual function due to the thinning of the outer nuclear layer. In addition to PDT, it is recommended that laser photocoagulation or subthreshold micropulse laser treatment of the leaking spot should be considered first, depending on the presence of the leaking spot and its location in relation to the macula center. Anti-vascular endothelial growth factor therapy can be considered if there is a combination of choroidal neovascularization and/or polypoidal choroidal vasculopathy. Other treatments that have not been demonstrated to be effective in evidence-based medicine are not recommended.
The concept of treatment of central serous chorioretinopathy (CSC) has evolved dramatically with the understanding of its pathogenesis recently. Initial clinical studies found that CSC is a selflimiting disease, therefore advocated observation or conservative treatment was recommended. Further study by fundus fluorescein angiography indicated that CSC results from barrier dysfunction of retinal pigment epithelium (RPE), which leads to serous RPE and (or) neural retinal detachment; so laser photocoagulation to close RPE leakage points by its thermal effects became a strategy to treat CSC. Recent study by indocyanine green angiography revealed that increased choroidal vascular permeability can induce high hydrostatic pressure and focal RPE detachment, resulting in mechanical breakage of RPE barrier. This is likely the major pathological basis of CSC now. Photodynamic therapy (PDT) can embolize of choroidal capillary network, thereby preventing choroidal leakage caused by increased capillary permeability, and thus cure the CSC. However the search for the pathogenesis and better treatment of CSC is far from over. Further investigation about pathogenesis and improvement of diagnosis and treatment is an urgent need for clinic work, but also major issues challenging the wisdom of an ophthalmologist. We need to work together to promote more and better clinical and basic research of CSC.
The etiology of intraocular inflammatory disease and its diagnosis is complicated. Currently available and newly emerging systemic and ocular examinations are of important to determine etiology of intraocular inflammatory disorders. But there also exists multiple misunderstanding, and the strategy of their application is not well defined, or even exaggerated. Unprincipled or randomly selection of auxiliary examination would not help for etiology determination, but bring unnecessary pain and economic burden to patients. Establishment of diagnosis thinking of intraocular inflammatory disease is helpful to standardize the diagnosis process of the disease, improve the diagnostic efficiency, and relief patients from the pain and financial burden that caused by too many useless examinations.
ObjectiveTo analyze the associations between the choroidal vasculature and submacular fluid (SMF) in central serous chorioretinopathy (CSC). MethodsA retrospective study. A total of 29 CSC patients (31 eyes) with complete records who visited the Department of Ophthalmology in Peking University People's Hospital from August 1, 2021 to March 1, 2023 were included in this study. The patients were divided into complete absorption and incomplete absorption groups according to the status of SMF in the last visit. All the patients underwent ultra-widefield swept-source optical coherence tomography angiography (UWF SS-OCTA) with a scanning range of 24 mm × 20 mm. The UWF SS-OCTA images were automatically analyzed in 9 regions (superotemporal, superior, superonasal, temporal, central, nasal, inferotemporal, inferior, and inferonasal). Alterations of choroidal vasculature in the nine subfields after SMF absorption were described, including choroidal thickness (CT), flow density of choriocapillaris layer, vessel density of large choroidal vessel layer, three-dimensional choroidal vascularity index (CVI), the mean choroidal vessel volume (mCVV), and the mean choroidal stroma volume (mCSV). The relevant factors affecting the complete absorption of SMF were additionally evaluated. ResultsAt baseline, CT (Z=2.859, P=0.004), mCVV (t=2.514, P=0.018), and mCSV (Z=2.958, P=0.003) in the superotemporal region of the affected eyes in the incomplete absorption group were significantly higher than those in the complete absorption group. Compared with baseline, at the last visit, the proportion of asymmetric vortex veins in the complete absorption group was significantly decreased (χ2=6.000, P=0.014), CVI in the superotemporal, superonasal, temporal, central, nasal, inferotemporal, and inferonasal regions (t=－4.125, t=－3.247, Z=－3.213, t=－2.994, t=－3.417, t=－3.733, t=－3.795; P=0.001, 0.006, 0.001, 0.010, 0.005, 0.003, 0.002), the mCVV of 9 regions (t=－2.959, t=－2.537, t=－2.235, t=－3.260, t=－3.022, t=－2.796, t=－2.747, Z=－2.107, t=－2.935; P=0.011, 0.025, 0.044, 0.006, 0.010, 0.015, 0.017, 0.035, 0.012) were significantly decreased. Compared to the complete absorption group, the choroidal blood flow changes in the non-complete absorption group were more limited, and CT in the upper region increased significantly at the last follow-up (t=2.272, P=0.037). Multivariate logistic regression analysis revealed that baseline CT in the superotemporal region may be an independent risk factor affecting the complete absorption of SMF (odds ratio=0.981, 95% confidential interval 0.965-0.997, P=0.021). ConclusionsIn the process of SMF absorption in CSC, significant reductions of choroidal blood flow were found in the large choroidal vessel layer, and there may be a locally compensatory increase in CT. In addition, baseline CT in superotemporal region is an independent risk factor affecting SMF absorption.
Objective To observe the relationship between endothelial constitutive nitric oxide synthase (ecNOS) genetic polymorphism and diabetic retinopathy（DR）of non insulindependent diabetes mellitus (NIDDM) patients of the Han nationality.Methods A total of 166 patients who clinical diagnosed with NIDDM as case group, 85 cases of patients (cataract or fracture) and healthy subjects without diabetes, hypertension and kidney disease,over 40 years old of age and without consanguinity between each other were selected as normal control group. Case group were divided into non-DR (NDR) group, nonproliferative-DR (BDR) group and proliferativeDR (PDR) group according to the result of fundus fluorescein angiography. Case group and normal control group subjects all were Han nationality. DNA was extracted from peripheral venous blood; the fourth 27 base pairs (bp) repeat polymorphism of ecNOS gene by was measured by polymerase chain reaction (PCR). Results The 27 bp repeat sequences within the ecNOS gene present in the Han nationality,allele b repeat 5 times, alleles a repeat 4 times. PCR results showed that there are 2 alleles and 3 genotypes in normal control, NDR, BDR and PDR group. The frequency of genotype bb、ab、aa were 80%, 16.5%, 3.5% in normal subjects; 77.2％, 13.9%, 8.9％ in NDR group; 80.5％, 17.1%,2.4％ in BDR group;78.3％, 13%, 8.7％ in PDR group,respectively. The allele frequency (chi;2 =1.841) and gene frequency (chi;2=3.847) were not statistically significant (P＞0.5) in normal control,NDR,BDR and PDR group. Logistic regression analysis showed that there is no relation between DR and ecNOS duplicated gene polymorphism. Conclusions There is 27 bp repeated polymorphism in 4th intron of ecNOS gene, which may not be associated with the DR of NIDDM in the Han nationality.
ObjectiveTo explore safe dosage of single intravitreal injection of ganciclovir (IVG) in healthy rabit eyes, and to explore retinal toxicity of different dosage of ganciclovir after continues intravitreal injection into the vitreous cavity of healthy albino rabbit eyes. MethodsTen healthy New Zealand albino rabbits were divided into 5 groups with 2 rabbits in each group. Each group was injected with 1 mg/0.025 ml, 2 mg/0.025 ml, 5 mg/0.025 ml, 10 mg/0.025 ml ganciclovir or 0.025 ml saline (control group). After 1 week of intervention, rabbits were examined by ultra-wide-angle fundus photography, optical coherence tomography (OCT) and full field electroretinogram (ERG). The maximum mixed response of rod and cone cells (Max-R) was measured under dark adaption conditions, cone response (Cone-R) and 30 Hz flicker response (30 Hz-R) were measured under light adaption conditions. Twenty-four healthy New Zealand albino rabbits were randomly divided into a low-dose experimental group, a low-dose control group, a high-dose experimental group, and a high-dose control group, with 6 rabbits in each group, with the right eye as the experimental eye. The rabbits in the high-dose experimental group were continuously injected with ganciclovir 2 mg/0.025 ml, once a week, for a total of 4 times. The rabbits in the low-dose experimental group were injected with 1 mg/0.025 ml ganciclovir, the induction period was 2 times/week, a total of 4 times; the maintenance period was 1 time/week, a total of 2 times. The rabbits in the high-dose control group and the low-dose control group were injected with 0.025 ml normal saline into the vitreous cavity respectively. Full-field ERG examination was performed 1 day before each injection and 1 week after the last injection. Max-R was measured under dark-adapted conditions, and Cone-R and 30 Hz-R were measured under light-adapted conditions. OCT was recorded before the first injection and one week after the last injection. One week after the last injection, the experimental rabbits in each group were sacrificed for hematoxylin-eosin staining, and the retinal structure was observed under a light microscope. The comparison of a-wave and b-wave amplitude of Max-R, Cone-R and 30 Hz-R amplitude at different time was performed by two independent sample nonparametric test. ResultsThere were no abnormal results of fundus photography, OCT and ERG after single intravitral injection of 1 mg or 2 mg ganciclovir. One week after single 5 mg IVG, fundus photography of rabbits showed vascular occlusion and preretinal hemorrhage and ERG showed slight decrease of amplitude of Max-R, Cone-R and 30 Hz-R. One week after single 10 mg IVG, retinal necrosis and exudative changes were also observed. OCT showed edema and unclear retinal structure in the necrotic area. ERG showed significant decrease of amplitude of Max-R, Cone-R and 30 Hz-R. After continuous IVG in high dose and low-dose experimental group, the amplitude of Max-R a wave (Z=－0.160, 0.000) and b wave (Z=－0.321, 0.000), Cone-R a wave (Z=－0.641,－0.641) and b wave (Z=－0.321, －0.160), and 30 Hz-R (Z=－0.321,－0.160) showed no difference compared to control group. No histologic evidences of retinal microstructure abnormalities were found in both groups. OCT and fundus photography before and after the intervention did not show any difference, either. ConclusionThere was no retinal toxicity of continuous 1 mg or 2 mg IVG recorded in albino rabbits.
Objective To investigate the difference of curative effect of various surgical methods for the treatment of idiopathic senile macular hole. Methods A retrospective analysis was made for 86 eyes with stage Ⅱ-Ⅳ idiopathic full-thickness macular hole treated with various modes of operation,ie, single vitrectomy (7 eyes),vitrectomy combined with autologous platelet concentrate (APC) as an adjuvant (40 eyes), vitrectomy with internal limiting membrane (ILM) peeling (14 eyes), vitrectomy with both ILM peeling and APC treatment (25 eyes). The main outcome measures included anatomic reattachment rate，change of visual acuity，findings of optic coherence tomography (OCT), Amsler grid and intra or postoperative complication evaluations. Results (1) In visual acuity improvement, the APC group (80.0%) was significantly better than anyone of the other three groups (P＜0.05). (2) In anatomic success rate, the single vitrectomy group was significantly lower than the vitrectomy with APC treatment group（87.5%）or vitrectomy with both ILM peeling and APC as an adjuvant group(92.0%)(P＜0.05). (3) There was no significant difference in operative complication and improvement of distortion of vision. Conclusion Vitrectomy combined with APC as an adjuvant for the treatment of idiopathic macular hole is helpful to improve both the anatomic success rate and postoperative visual acuity. The usage of ILM peeling technique could improve the anatomic reattachment rate, but the vision prognosis of ILM peeling patients is not as good as the patients of APC as an adjuvant. (Chin J Ocul Fundus Dis, 2002, 18: 196-198)