Central serous chorioretinopathy(CSC), first reported in 1866, is now recognized as the fourth most common macular fluid leakage disease after age-related macular degeneration, diabetic macular edema, and retinal vein occlusion. Although self-limiting in most cases, chronic CSC can cause the outer retinal atrophy and choroidal neovascularization, resulting in serious visual impairment. CSC used to be classified as a macular disease, or an acquired disease involving the macula. Thanks to the rapid development and application of fundus imaging technology, this concept has changed. Since 2013, CSC has been listed as choroidal vessel/Bruch's membrane disease, or choroidal disease, in the authoritative retinal books. CSC now belongs to a common phenotype of pachychoroidal diseases. The pathogenesis of CSC lies in choroidal vessel dilation, venostasis, remodeling and anastomosis between vortex veins, resulting in increased venous pressure and damage in choroidal capillaries, retinal pigment epithelium and outer blood retinal barrier, and then macular fluid leakage. However, the risk factors or causes of choroidal vessel abnormalities have not been elucidated. Current intervention strategies focus on eliminating macular fluid, and there is no effective treatment for eliminating etiology or risk factors. Therefore, the pathophysiology and etiological treatment of CSC deserve more attention.

Regenerative medicine(RM)is an emerging interdisciplinary field that integrates molecular and cellular biology, gene editing, biomaterials and bioengineering to activate one's own potential, replace, repair or regenerate damaged tissues and organs. Ophthalmology is one of the most active and promising fields in RM, and is highly valued by governments and research institutions around the world. Its progress represents the most cutting-edge aspects of medical and ophthalmic research. Currently, the treatment targets of ophthalmic RM include ocular surface and corneal diseases, retinal diseases such as diabetic retinopathy, age-related macular degeneration, inherited retinal diseases, glaucoma and other irreversible ophthalmic disorders. Some preclinical or clinical trials have shown encouraging results. The challenges for RM include ethics, cell delivery, long-term efficacy and safety, etc. We herein briefly introduce the relevant concepts, research status and progress, and look forward to continuous new achievements in domestic RM.

Immune checkpoints refer to a class of receptors or ligand molecules expressed on the surface of immune cells, mainly T cells, as multiple inhibitory pathways in the immune system. Their crucial roles in immune regulation were gradually revealed in 1990s. The clinical application, namely immune checkpoint therapy(ICT), has achieved revolutionary breakthroughs in the field of tumor immunotherapy since 2010. However, ICT in the treatment of eye tumors is relatively complex and full of challenges. Immune checkpoint inhibitors(ICI)have brought new hope for the treatment of ocular tumors, especially metastatic uveal melanoma and certain ocular adnexal lymphomas, but ICI application is severely restricted by ocular immune privilege, the blood-ocular barrier and potential ocular toxicity. At present, the main role of ICT for ocular tumors is for metastatic lesions, especially liver metastases. The treatment of primary intraocular tumors is still in the exploration stage of local administration. ICT treatment decisions must be highly individualized, with a strict assessment of the risk-benefit ratio, and priority should be given to clinical trials. Future research needs to focus on overcoming delivery barriers, accurately identifying beneficiary populations, developing safer and more effective combined strategies, and exploring novel immunotherapies, in order to ultimately improve the prognosis and quality of life of patients with ocular tumors.

AIM: To observe the outcome of intravitreal balanced salt solution(BSS)injection to increase intraocular pressure(IOP)after extrascleral subretinal fluid drainage, then scleral buckling(SB)to treat superior bullous retinal detachment(SBRD), and compare it with the effect of conventional surgery(without any intravitreal filling)and postoperative air filling.METHODS: Retrospective case-control study. A total of 72 patients(73 eyes)who underwent SB for SBRD from January 2018 to December 2022 in ophthalmology department of Xijing Hospital were included. The extrascleral subretinal fluid drainage was performed in all eyes. According to whether intravitreal injection was performed and different injections, patients were divided into three groups: with 24 cases(24 eyes)in the conventional group(no intravitreal injection), 23 cases(23 eyes)in the air group(sterile air was injected after surgery), and 25 cases(26 eyes)in the BSS group(BSS was injected during extrascleral subretinal fluid drainage). All patients were followed up until subretinal fluid was absorbed completely. The average surgery time, postoperative IOP, retinal reattachment rate, subretinal fluid absorption, visual acuity(LogMAR)and major complications were compared.RESULTS: All surgeries were completed successfully. The average surgery time of the conventional group, air group and BSS group were 63.17±13.22, 61.65±15.55 and 57.30±11.70 min, respectively. There had no significant difference among these groups(F=0.825, P=0.443). On the first post-operative day, the average IOP of the conventional group, air group and BSS group were 13.69±2.69, 16.40±2.86 and 18.35±2.88 mmHg, respectively. The average IOP of the air group and the BSS group were significant higher than that of the conventional group(F=17.18, P<0.001). Primary reattachment rates were 88%, 96%, and 100%, respectively. The postoperative BCVA was 0.71±0.42, 0.59±0.44, and 0.91±0.50, respectively, which were significantly higher than those before operation(all P<0.05), but there was no significant difference among groups(F=3.046, P>0.05). The main complications included subretinal hemorrhage in 1 eye from the conventional group and 1 eye from the air group, and a new retinal tear in 1 eye from the air group, resulting in localized retinal detachment.CONCLUSIONS: For SBRD patients with hypotony during SB surgery, intravitreal injection of BSS to properly increase the IOP and then complete the surgery can improve the reattachment rate and reduce postoperative complications. This method is safe and effective for selected SBRD patients.

ChatGPT is a large language models(LLMs)that uses deep learning techniques to produce human-like responses to natural language inputs. It belongs to the family of generative pre-training transformer(GPT)models currently publicly available developed by OpenAI in November 2022. ChatGPT is capable of capturing the nuances and intricacies of human language, generating appropriate and contextually relevant responses. It can assist medical professionals in various tasks, such as research, diagnosis, patient monitoring, and medical education, from identifying research programs to assisting in clinical and laboratory diagnosis, to know new developments in their fields and scientific writing. ChatGPT has also attracted increasing attention and widely used in ophthalmology. However, the use of ChatGPT and other artificial intelligence tools in such tasks comes now with several limitations, ethical and legal concerns, such as credibility, plagiarism, copyright infringement, and biases. Future research can focus on developing new methods to mitigate these limitations while harnessing the benefits of ChatGPT in medicine and related aspects.

With the tremendous progress in fundus imaging and histopathology over the past decade, the understanding of age-related macular degeneration (AMD) has taken a qualitative leap. AMD is defined as a progressive neurodegenerative disease of photoreceptors and retinal pigment epithelium (RPE) characterized by extracellular deposits under RPE and the retina, including drusen, basal laminar and linear deposits, and subretinal drusenoid deposits, that can evolve to atrophy of the retina, RPE and choroid and neovascularization in the choroid and/or retina. It is the leading cause of blindness and visual impairment in older populations, despite recent advances in treatments. AMD is a multifactorial disease with genetic and environmental factors including advanced age, smoking, high-fat diet, and cardiovascular disorder to enhance the disease susceptibility. The physiopathologic mechanism includes inflammatory processes (complement pathway dysregulation, inflammasome activation), intrinsic (e.g., photo-oxidation) and extrinsic oxidative insult to the retina, age-related metabolic impairment (mitochondrial, autophagic and endoplasmic reticulum stress). Autophagy dysfunction and local inflammation in aged RPE specially result in the extracellular deposits, cell death and AMD. Further investigation of the pathogenesis of AMD will provide with new therapeutic targets and strategy for prevention and treatment of the disease in the early stages.

The prevalence of diabetes mellitus in adults of China has reached 12.8%. Diabetic retinopathy (DR) accounts for approximately 1/4-1/3 of the diabetic population. Several millions of people are estimated suffering the advanced stage of DR, including severe non-proliferative DR (NPDR), proliferative DR (PDR) and diabetic macular edema (DME), which seriously threat to the patients' vision. On the basis of systematic prevention and control of diabetes and its complications, prevention of the moderate and high-risk NPDR from progressing to the advanced stage is the final efforts to avoid diabetic blindness. The implementation of the DR severity scale is helpful to assess the severity, risk factors for its progression, treatment efficacy and prognosis. In the eyes with vision-threatening DR, early application of biotherapy of anti-vascular endothelial growth factor can improve DR with regression of retinal neovascularization, but whether it is possible to induce capillary re-canalization in the non-perfusion area needs more investigation. Laser photocoagulation remains the mainstay treatment for non-center-involved DME and PDR.

Drusen is one of the early hallmark changes of AMD. The oxidative stress and inflammatory reaction caused by oxidative phospholipids (OxPLs) in drusen can lead to retinal pigment epithelium (RPE) cell death (apoptosis, pyroptosis, etc.) and the formation of choroidal neovascularization, which is the pathogenesis of AMD. Pyroptosis, also known as inflammatory necrosis, is one of the main forms of OxPLs induced cell death. Proinflammatory factors released by pyroptic cells can in turn aggravate the inflammatory reaction, leading to further damage. In order to prevent AMD, inflammatory response and cell death may be reduced by regulating lipid metabolism, reducing OxPLs endocytosis and increasing cholesterol efflux. In-depth understanding effects of OxPLs, inflammation and RPE pyrosis in the pathogenesis of AMD in elucidate the pathogenesis of AMD and to seek new treatment measures has important clinical significance.

Retinal break is the cause of primary retinal detachment,which remains a main cause for visual loss,and closure of the breaks is the principle of treatment.Currently surgical treatment can successfully reattach the retina in most cases.However,some basic questions still beset treatment of the disease,such as the cause responsible for development of retinal breaks and how to prevent it,and how the visual recovery can be satisfactory after reattachment surgery.Recent research indicates that the development of retinal breaks is associated with the process of vitreous liquefaction,posterior vitreous detachment (PVD) and abnormal vitreoretinal adhesion and traction.The retinal breaks can occur in the posterior margin of the vitreous base in the eye with complete PVD.Partial PVD may cause posterior breaks especially in cases of myopic traction maculopathy associated with schisis-like thickening in the outer retina (foveoschisis) and vitreomacular traction.It is known that microstructural changes and atrophy of the macula,and epiretinal membrane formation are the reasons for poor vision after the retina is reattached.Therefore,more attention should be paid to further understand the vitreous pathology and traction mechanism,to research for methods of its clinical evaluation and strategy of prevention and treatment,and to accelerate visual recovery after reattachment surgery,in order to raise the standard of the disease treatment.

Background Researches have demonstrated that ocular hypertension induces the ischemia-reperfusion of retina and further leads to the degeneration of retinal ganglion cells,but its mechanism is beyond understanding.Objective The present study aims to observe the effects of static pressure on the morphology,proliferation activity and viability of cultured retinal microvascular endothelial cells (RMECs) and evaluate the expression of ET-1 and NO in these cells under variant static pressure.Methods RMECs were isolated from 30 healthy Wistar rats and cultured using explant culture method by Ⅷ factor antibody and PECAM-1 antibody.The static pressure of 1.33kPa,2.67kPa,5.33kPa and 10.67kPa was used in culture bottle respectively.The RMECs without static pressure were used as normal control group.The morphology of RMECs under the different static pressure was observed by inverted phase contrast microscopy,and the number of RMECs was counted using the counting plate.Cellular viability was studied by trypan blue staining.The changes of ET-1 and NO_2~-/NO_3~-,two metabolic products of NO,in the medium were detected by radioimmunoassay and Griess's nitrate reductase method.The expression of ET-1,eNOS and iNOS mRNA in RMECs was analyzed by semi-quantitative RT-PCR 24 hours after treatment of variant static pressure.Results Cultured RMECs sticked well at 24 hours and reached to confluence at 48 hours and showed the red fluorescence for Ⅷ factor antibody and PECAM-1 antibody.Enlargement of nuclei,extenders of cell bodies and suspension of RMECs in medium were observed.The number of RMECs was gradually increased.The cell viability was reduced with the raise of static pressure among these four groups(F=12.205,P＜0.01;F=11.180,P＜0.01).The static pressure increased the content of ET-1 released by RMECs in 2.67kPa,5.33kPa and 10.67kPa of static pressure groups,and concentrations of NO_2~-/NO_3~- in the medium showed a significant increase in 5.33kPa and 10.67kPa of static pressure groups compared with normal and 1.33kPa of static pressure groups(P＜0.01).The expressions of ET-1 mRNA,eNOS mRNA and iNOS mRNA were considerably enhanced in 5.33kPa and 10.67kPa of static pressure groups compared with normal control group(P＜0.01).Conclusion Raised static pressure causes the alteration of RMGCs structure and morphology.Static pressure could upregulate the expressions of ET-1,eNOS and iNOS mRNA in RMECs and increase the release of ET-1 and NO.This pathway might be one of pathologic mechanisms of retinal injury induced by high intraocular pressure.