Abstract:AIM: To evaluate the diopter errors and safety of secondary intraocular lens(IOL)implantation in the ciliary sulcus using a modified incision procedure in children with bilateral aphakia.

METHODS: The data of 12 children(24 eyes)with bilateral aphakia who had undergone secondary foldable IOL implantation in the ciliary sulcus using a modified incision procedure from 2020 to 2021 were retrospectively reviewed. Incision-related complications were analyzed intraoperatively and at 1 d and 1 mo postoperatively. Best-corrected visual acuity(BCVA), axial length(AL), white-to-white(WTW), and refractive outcomes in terms of preoperative reserved diopters(PRD)and actual equivalent spherical diopters(AESD). The patients were divided into two groups by age(≤7 and >7 a), AL(<23 and ≥23 mm)and WTW(≤11.5 and >11.5mm), and the diopter errors between their AESD and PRD predicted based on the measurement results were compared.

RESULTS: The patients comprised 9(75%)boys and 3(25%)girls. Two(17%)patients had anterior subcapsular cataracts, 4(33%)had posterior polar cataracts, and 6(50%)had nuclear cataracts. The mean age at cataract extraction was 6.4±1.61(3.4-8.9)mo. The mean interval between cataract extraction and secondary IOL implantation was 6.8±1.82(4.4-11.5)a. The mean preoperative BCVA was 0.49±0.33(1.0-0.1)LogMAR. The mean postoperative BCVA was 0.38±0.32(1.0-0.0)LogMAR. The mean AL was 23.56±1.96(19.00-26.38)mm, and the mean WTW was 11.5±0.92(9.3-13.9)mm. The mean PRD was 1.57±0.60(0.73-2.77)D, the mean AESD was 0.57±0.55(-0.50 to 1.75)D, and the mean difference between the AESD and PRD was -0.99±0.52(-2.22 to 0.32)D. The differences in the AESD and PRD between the groups according to age, AL and WTW were not statistically significant(P=0.59, 0.56, and 0.53, respectively).

CONCLUSION: IOL implantation in the ciliary sulcus after a modified incision is safe and feasible for children with aphakia. It is necessary to subtract approximately 1 D of IOL power from the formula-selected power when implanting an IOL in the ciliary sulcus. Age, AL, and WTW do not significantly affect the difference.

Abstract:AIM: To analyze ocular biometric parameters among candidates for cataract surgery.

METHODS: This cross-sectional study was conducted on 4 607 cataract patients(4 607 eyes)in Farabi Eye Hospital, Tehran, Iran from January 2017 to September 2021. Axial length(AL), keratometry(Kf, Ks and Km), and anterior chamber depth(ACD)were assessed using IOLMaster 700. All eyes were categorized into three groups based on AL: short eyes(22 mm25 mm)and ACD as follows: low(3.00 mm3.60 mm).

RESULTS: The mean age of patients was 60.3±14.1(range 8-95)years \〖2 243(48.69%)female and 2 364(51.31%)male\〗. The AL, ACD and mean keratometry ranges were 23.1 to 23.4 mm, 3.1 to 3.2 mm and 44.50 to 45.00 diopter(D), respectively. The mean amount of ACD in the long eyes group was significantly higher than the normal and short eyes group(P<0.001). The mean AL in the high ACD group was significantly higher than low and normal ACD patients(P<0.001). But the mean of Kf, Ks and Km in the low ACD and long eyes group was significantly higher than in high ACD and short AL groups(P<0.001).

CONCLUSION: Those candidates with long eyes had deeper ACD with flatter cornea; while short eyes had shallower ACD with steeper cornea. Also, patients with high ACD had longer AL with flatter cornea, and patients with low ACD had lower AL with steeper cornea.

Abstract:AIM: To investigate the protective effect of eugenol against Fusarium solani(F.solani)-induced fungal keratitis(FK)in mice and to preliminarily explore possible underlying mechanisms.

METHODS: A modified epifluorescence microscopy method was used to prepare the FK mouse model. An equal amount of DMSO(0.05%)was applied to the conjunctiva of the right eye of rats in the dimethyl sulfoxide(DMSO)group. The eugenol group was prepared by applying eugenol(160 μg/mL)to the conjunctival sac of the right eye of mice. The insulin-like growth factor-1(IGF-1)group was coated with the PI3K/AKT pathway activator IGF-1(10 nmol/mL)in the conjunctival sac of the right eye in addition to the administration of eugenol. The corneal morphology was observed under a slit-lamp microscope on days 1, 3, and 5 of inoculation with F.solani suspension, respectively. Hematoxylin eosin(HE)staining was used to assess corneal histopathological damage. The bacterial load of corneal tissue was determined. Enzyme-linked immunosorbent assay and Western blot were used to analyze the levels of inflammatory mediators interleukin-6(IL-6)and interleukin-1β(IL-1β)and the expression of PI3K/AKT pathway proteins.

RESULTS: Eugenol treatment improved the morphological symptoms of keratitis and inflammatory response in FK mice, and reduced corneal pathologic tissue damage and fungal load. At 3 d after F.solani infection, corneal tissue IL-6 levels were significantly higher and IL-1β levels were significantly lower in the eugenol group compared with the DMSO group(both P<0.05); corneal tissue IL-6 levels were significantly higher and IL-1β levels were significantly lower in the eugenol group than in the IGF-1 group(both P<0.05). At 5 d after infection, both IL-6 and IL-1β levels in corneal tissue of the eugenol group were significantly lower than those of the DMSO and IGF-1 groups(P<0.05); compared with the DMSO group, the expression of p-PI3K and p-Akt in the corneal tissues of the eugenol group was significantly reduced(P<0.05); the expression of p-PI3K and p-Akt in corneal tissues was significantly lower in the eugenol group than that of the IGF-1 group(both P<0.05).

CONCLUSION: Eugenol may attenuate F.solani-induced corneal inflammation by inhibiting the PI3K/AKT pathway, and it has a protective effect against F.solani keratitis in mice.

Abstract:AIM:To establish a model of meibomian gland dysfunction in rats induced by eyeliner tattoo and investigate its potential mechanisms.

METHODS:A total of 40 SD rats were selected, with 30 randomly chosen to have eyeliner tattoo applied their right eyes and designated as the eyeliner group. The remaining 10 rats were not given any treatment and served as the normal group. The corneal morphology of both groups was observed using a slit lamp at 1, 2, and 4 wk after establishment, and the tear film break-up time(BUT), Schirmer I test(SIt), corneal fluorescein staining score, and corneal irregularity score were calculated. The corneal Placido rings were examined using an ocular surface analyzer, and the corneal tissue structures of both groups were observed under a confocal microscope. After 4 wk and completion of clinical indicator recording, the eyeballs and upper and lower eyelid tissues were taken for pathological examination. The meibomian gland structures were observed through HE staining, the conjunctival goblet cells were observed using PAS staining, and the lipid droplets were observed with ORO staining.

RESULTS:The slit lamp examination results showed that the eyeliner group rats exhibited in situ black pigmentation in the eyelids, with no eyelid deformation or scarring. The corneal epithelium was rough, with positive fluorescein staining, presenting as spotty staining that worsened over time. Compared with the normal group, the BUT was significantly shortened, tear secretion volume was significantly decreased, and the corneal fluorescein staining score and corneal irregularity score were significantly increased at 1, 2, and 4 wk after modeling in the eyeliner group(all P<0.01). The corneal confocal microscopy results showed a decrease in corneal epithelial cells in the eyeliner group, with the appearance of abnormally bright cells, and inflammatory cell infiltration visible in the stromal layer. The ORO staining results revealed a decrease in lipid droplets in the eyeliner group, showing a downward trend with increasing observation time. The HE staining results showed that pigment blocked the meibomian gland openings in the eyeliner group, and the density of meibomian gland acini showed a downward trend over time. The PAS staining results showed a decreasing trend in the number of PAS-positive cells in the eyeliner group.

CONCLUSION:Eyeliner tattoo can induce meibomian gland dysfunction, and the blockage of meibomian gland openings caused by the pigment particles used may be an important cause of meibomian gland dysfunction.

Abstract:AIM: To avoid the problem of retinal dissection in guinea pig large eyeball tissue sections, different methods were used to optimize the fixation effect of the posterior pole of the eyeball.

METHODS: A total of 75 normal guinea pigs(2 weeks old)were randomly divided into 5 large groups. Group A(1-3 small groups), the entire eyeball was fixed with FAS, Davidson fixative 1(D1), and Davidson fixative 2(D2)for 24 h; group B(4-6 small groups), the entire eyeball was fixed with FAS, D1, and D2 for 1 h, then cut the cornea and fix it in their respective fixatives for 2 h; group C(7-9 small groups), the eyeball was fixed in FAS, D1, and D2 for 1 h, divided into left and right halves along the direction of the optic nerve, and then placed them in their respective fixation solutions for 2 h; group D(10-12 small groups), after fixation for 3 h in FAS, D1, and D2, the eyeball was divided into left and right halves along the optic nerve direction; group E(13-15 small groups), the cornea was cut after fixation for 3 h in FAS, D1, and D2. Hematoxylin-eosin(HE)staining was used to compare the fixation effect on posterior eyeball in each group.

RESULTS: After fixation, the surface of the eyeballs in groups, 1-6 and 11-15 was smooth and round, with a transparent and bright color. In groups 7-10, the eyeballs were sunken, wrinkled, and deformed. The HE staining showed that the eyeball morphology of groups 1, 5, 6, 14, and 15 was significantly better than the other groups, with a regular internal tissue structure. The eyeballs of the other groups were sunken and wrinkled, and the internal tissue was curled and tangled, with severe retinal detachment. In groups 1, 5, 6, 14, and 15, the retina, choroid, and sclera tissues of group 14 were closely connected, without obvious retinal detachment, rupture, or curling. The tissue structure was clear and visible, and the cells were arranged neatly.

CONCLUSION: The fixation effect of cutting the cornea after fixing guinea pig eyeball with D1 fixative for 3 h is the most ideal, and this operation method is simple and suitable for studying the related structures of the posterior pole of the eye.

Abstract:AIM: To analyze the corneal morphological characteristics of school-age children, and provide reference for the examination of refractive errors, corneal lesions, and treatment in school-age children.

METHODS: Children aged 6-12 years in our hospital from March 2020 to June 2023 were included as the research objects, and they are divided into emmetropia group(-0.25 D≤SE≤+0.25 D)and myopia group(-6.00 D≤SE<-0.25 D)according to spherical equivalent(SE). The flat curvature(K1), steep curvature(K2), mean curvature(Km), radius of curvature(Rm), white-to-white(WTW)and corneal central thickness(CCT)were measured by Pentacam anterior segment analyzer. The corneal morphological differences between the emmetropia group and myopia group, boys and girls and children of different ages were analyzed.

RESULTS: In the emmetropia group, the anterior corneal surface Km was 42.84±0.61 D, Rm was 7.85±0.15 mm, the posterior corneal surface Km was -6.23±0.04 D, Rm was 6.77±0.15 mm, WTW was 11.89±0.28 mm, CCT was 557.77±22.44 μm; in the myopia group, Km was 43.68±0.62 D, Rm was 7.72±0.16 mm, Km was -6.49±0.03 D, Rm was 6.64±0.17 mm, WTW was 12.17±0.27 mm, CCT was 553.24±22.23 μm. There was significant difference in corneal morphology between the emmetropia group and the myopia group(both P<0.01). Correlation analysis showed that corneal morphology was significantly correlated with age and gender.

CONCLUSION: The corneal morphology of school-age children is not fixed, and the occurrence of myopia is not only related to the growth of axial length, but also significantly related to the changes of corneal morphology.

Abstract:AIM: To detect the expression levels of long non-coding RNA(lncRNA)X-inactive specific transcript(XIST)and silencing information regulatory factor 2 associated enzyme 1(SIRT1)in serum of patients with type 2 diabetes mellitus(T2DM), and to explore their correlation with diabetic retinopathy(DR)and their diagnostic value.

METHODS: Prospective study. A total of 214 patients with T2DM admitted to our hospital from January 2022 to February 2023 were selected as the research subjects. Based on whether retinopathy occurred, they were divided into 126 cases(126 eyes)in the non-DR group and 88 cases(88 eyes)in the DR group. An additional 130 healthy individuals who underwent a physical examination during the same period were selected as the control group. The serum levels of lncRNA XIST and SIRT1 in the three groups were measured and compared. The relationship between lncRNA XIST and SIRT1 expression with DR was analyzed using Pearson's method. The receiver operating characteristic(ROC)curve was used to evaluate the predictive value of serum lncRNA XIST, SIRT1, and their combination for DR. Multivariate Logistic regression analysis was performed to investigate the factors affecting the occurrence of DR in T2DM patients.

RESULTS: Compared with the control group, the levels of serum lncRNA XIST and SIRT1 in the non-DR group and DR group were successively decreased(all P<0.05). The levels of serum lncRNA XIST and SIRT1 were positively correlated in DR patients(r=0.639, P<0.05). ROC analysis showed that the area under the curve(AUC)for predicting DR by combining serum lncRNA XIST and SIRT1 was 0.940, which was higher than the AUC by serum lncRNA XIST and SIRT1 alone(0.855, 0.875). Logistic regression analysis showed that lncRNA XIST(OR=0.752)and SIRT1(OR=0.694)were influencing factors for the occurrence of DR(both P<0.01).

CONCLUSION: The serum levels of lncRNA XIST and SIRT1 are both lower in DR patients, and the combination of lncRNA XIST and SIRT1 has a better assessment capacity for the occurrence of DR.

Abstract:Angiogenesis is a key step involving physiological and pathological processes, and pro/antiangiogenic factors are involved in angiogenesis throughout. Melatonin is a product synthesized by the pineal gland of the human brain and acts in various systems of the body. This article briefly describes the wide range of biological roles and physiological functions of melatonin, and summarizes that melatonin regulates pro-/anti-angiogenic factors(e.g., vascular endothelial growth factor/matrix metalloproteinase)under different conditions and is involved in angiogenesis in fundus diseases(e.g., age-related macular degeneration, diabetic retinopathy, and central serous choroioretinopathy); in addition, it also summarizes that melatonin regulates various cytokines, inflammatory factors and signaling pathways to produce anti-inflammatory, antioxidant and immune responses in fundus diseases, and thus obtaining the application and potential treatment of melatonin in fundus vascular diseases, with a view to providing new ideas and therapeutic targets for the treatment of fundus diseases.

Abstract:Small incision lenticule extraction(SMILE)is a flapless femtosecond laser-assisted refractive surgery, which is applied in the treatment of refractive errors. Since the earliest publications about SMILE in 2011, the concept of a refractive surgery performed through a small incision without the complications associated with the flap creation, has led to an increased interest in the ophthalmologic field. Lower impact on corneal biomechanical, less dry eye risk and less stromal layer exposure were some benefits this innovative technique had aroused. It is also stable, safe and effective in treating myopia and myopic astigmatism. Despite of the advantages, the implementation of SMILE is challenging, and various postoperative complications can emerge, including dry eye, infectious keratitis, diffuse lamellar keratitis, transient light sensitivity syndrome, corneal ectasia, pressure induced stromal keratitis, epithelial ingrowth, vision-related changes, etc. Early recognition and proper management of these complications are necessary for optimizing refractive outcomes. This article reviews the risk factors, clinical features, management and prevention of various complications focusing on SMILE.

Abstract:Congenital cranial dysinnervation disorders(CCDDs)are a group of diseases with congenital non-progressive developmental abnormalities or absence of one or more cranial nerves, resulting in primary or secondary abnormalities of cranial nerves innervating the extraocular muscles. CCDDs can be sporadic or hereditary, and may be accompanied by systemic abnormalities. In recent years, with the research progress of neuropathology, neuroimaging, and genetics, it has not only been clarified that the cause of eye movement disorder in CCDDs is neurogenic, but also been found the pathogenic genes of CCDDs, including SALL4, HOXA1, KIF21A, PHOX2A, TUBB3, and HOXB1, etc. In this review, the relevant domestic and international literatures on the molecular genetics and neuroscience of CCDDs in recent years are reviewed, aiming to address how the causing gene mutations of CCDDs affect brain neural development and further lead to congenital abnormal cranial nerve innervation, in order to provide references for the clinical and basic research of CCDDs.

Abstract:Age-related macular degeneration(ARMD)is one of the leading causes of irreversible blindness in the elderly. Anti-vascular endothelial growth factor(VEGF)drugs have become the first-line treatment for neovascular ARMD, which has greatly changed the prognosis. However, dry ARMD still lacks effective treatment means, focusing on prevention. At present, several clinical treatment methods are being explored, including antioxidant therapy, complement therapy, neuroprotective therapy, gene therapy, etc. This review mainly summarizes the existing clinical trials and their progress on the treatment of dry ARMD, in order to provide future prospects for the treatment of dry ARMD. A number of clinical trials have already produced promising results for the treatment of dry ARMD, and it is believed that more and more clinical trials will be successful in the near future to provide more effective treatments for patients with dry ARMD.

Abstract:Corneal transplantation is an effective treatment for corneal blindness, and it is the only hope for patients with corneal blindness. Cornea has no blood vessels and no lymphatic vessels, which is called immune privilege organ, so the success rate of corneal transplantation is significantly higher than that of other organ transplantation, but the rejection reaction after corneal transplantation is still the main reason for the failure of corneal transplantation. The directional movement of immune cells to lymphoid tissue and inflammatory sites is the mainly immune response after organ transplantation. And the regulatory T cells(Treg)play a key role in immune regulation, which can induce immune tolerance by regulating and inhibiting the activation of effector T cells and reduce the rejection reaction after corneal transplantation. In addition, this review also discussed the effectiveness of applying cordyceps sinensis extract FTY720 to enhance the function of Treg. Based on this, we briefly reviewed the sources, mechanism of action and treatment of Treg after corneal transplantation, so as to provide some reference for the subsequent clinical application transformation and basic research.

Abstract:Keratoconus is a progressive disease that seriously affects the eyesight of young people. Keratoconus often causes high myopia, irregular astigmatism, and some patients with advanced corneal scar, visual acuity significantly decreased. In the course of diagnosis and treatment of keratoconus, refractive reconstruction of keratoconus is the focus of clinical attention. After years of research and exploration, a variety of treatment methods in different stages of disease(non-progressive, progressive, advanced)for keratoconus patients refractive reconstruction, so that they can obtain good visual function. This paper mainly reviews the refractive reconstruction schemes of keratoconus in different periods, analyzes the advantages and disadvantages of various treatment schemes at home and abroad, and summarizes the characteristics of different treatment methods, with a view to providing theoretical reference and new treatment ideas for the diagnosis and treatment of keratoconus.

Abstract:Femtosecond laser-assisted cataract surgery(FLACS)has been used for more than 10 years, with its safety and precision well-verified. In recent years, FLACS has been gradually applied to patients with glaucoma and cataracts, especially those patients with primary angle closure glaucoma(PACG). The unique anatomical characteristics of PACG increase the difficulty of lens extraction and potential complications in conventional phacoemulsification surgery, highlighting the distinct advantages of FLACS in these patients. Recently, the application of FLACS combined with minimally invasive glaucoma surgery(MIGS)in patients with open angle glaucoma, and goniosynechialysis(GSL)in patients with angle-closure glaucoma, and even in patients with filtering blebs after anti-glaucoma surgery, has been reported. The indications for FLACS are increasingly expanding. FLACS can cause a transient intraoperative increase in intraocular pressure(IOP), and ocular parameters can have a certain impact on IOP. The long-term effects on IOP require further research. More attention should be paid to the impact of FLACS on visual function in glaucoma patients and the related complications that may arise. This article reviews the application of FLACS in different types of glaucoma, its effects on IOP and visual function, specific complications, and application prospects.

Abstract:Diabetic retinopathy(DR)is one of the common causes of visual impairment and blindness in adults, which is caused by various pathogenesis. Although the mechanism of DR has not been elucidated yet, the destruction of blood-retinal barrier is a key process. As a highly endothelial-specific factor in promoting the growth of vascular endothelial cell, vascular endothelial growth factor(VEGF)plays a crucial role in the formation of pathological retinal neovascularization and the destruction of blood-retinal barrier. Therefore, a comprehensive understanding of the etiology and pathogenesis of blood-retinal barrier damage promoted by VEGF is critical for exploring the pathogenesis of DR. In this study, the underlying relationship between VEGF and the mechanism of blood-retinal barrier damage, including retinal vascular endothelial cell permeability, vascular inflammatory response, apoptosis, oxidative stress, mitochondrial damage and endoplasmic reticulum stress, with a view to providing a reference for the study in VEGF in the pathogenesis of blood-retinal barrier damage in DR.

Abstract:Diabetic retinopathy(DR)is one of the most common retinal complications of diabetes could cause irreversible loss of central vision in the working-age population. Current studies showed that systemic risk factors, inflammatory response, and oxidative stress played a central role in the development of DR. Although traditional sequencing methods have provided valuable insights into the pathogenesis of DR, offering crucial guidance for clinical diagnosis and treatment, they still possess certain limitations. In recent years, the emerging single-cell RNA sequencing technology(scRNA-seq)has enabled precise analysis of mRNA transcriptomes at the single-cell level. This technique accurately identifies novel cell subtypes in retinal diseases, detects rare cells, and reveals intercellular heterogeneity. It contributes to elucidating the pathogenesis and development of retinal diseases, and facilitates exploration of gene regulatory relationships associated with these disorders to provide valuable insights for future precision medicine. This article reviews the technology of single-cell sequencing and its application in DR research. It also explores the mechanisms of different types of cells associated with DR, aiming to enhance the utilization of scRNA-seq in DR research and identify potential therapeutic targets to improve clinical diagnosis and treatment of DR.

Abstract:Myopia is a serious threat to children's visual health, and high myopia can not only cause vision loss, but also lead to severe complications and even blindness. In recent years, with the rising incidence of myopia and the increasing awareness of myopia, the problem of myopia has been widely concerned. At present, the specific mechanism of the incidence and progression of myopia remains ambiguous, and it is generally believed that the sclera is the effector of myopia. With the development of myopia and axial growth, the structure and function of the eyeball change accordingly. The high rates of axial length growth leads to scleral remodeling and accelerated thinning of the posterior pole sclera. Myopia changes the normal tissue structure and biomechanical properties of the sclera, and the regulation of related gene expression is the key to these changes. With the help of myopia animal models and gene sequencing technology, a large number of researchers have found that scleral extracellular matrix remodeling is closely related to the occurrence and development of myopia. This paper discusses the changes of sclera structure and related genes in the development of myopia. It provides ideas for exploring the mechanism of scleral remodeling in myopia and finding new target of treatment.

Abstract:Myopia is becoming more and more common all over the world, and the incidence of myopia is gradually increasing. Many treatments have been used to prevent and control myopia, including optics, drugs, environment or behavior, but the results are different and lack standardization. At present, many experiments have proved that peripheral defocus technology has a certain effect on myopia control. Based on this technology, three kinds of framed eyeglass lenses with peripheral defocus design, namely defocus incorporated multiple segments(DIMS), highly aspherical lenslets(HAL)and cylindrical annular reactive elements(CARE), are commonly used in medical and optometry institutions in China. These lenses provide not only clear vision in the central area, but also a certain amount of myopic defocus in the periphery to control the progression of myopia. This paper aims to focus on the design principle and myopia prevention and control effect of the above three peripheral defocus lenses, and evaluate their effectiveness in clinical practice.

Abstract:Since the first intraocular lens(IOL)was implanted by Harold Ridley in 1949 and the widespread use of depth-of-focus extended intraocular lens(EDOF IOL)clinically, the IOL has been constantly updated and developed, aiming to provide patients with good postoperative visual quality. The residual astigmatism is one of the important factors affecting the postoperative visual quality of cataract patients, 35%-40% of cataract patients have astigmatism of 1.00 D, and 19%-22% have astigmatism of 1.50 D. Therefore, it is important to understand the inclusiveness of EDOF IOL for astigmatism, so that the right IOL can be selected for the patient. This article summarizes the inclusiveness of different types of EDOF IOL for astigmatism and their advantages and disadvantages, with the expectation that it will provide a reference in selecting EDOF IOL for patients with different residual astigmatism.

Abstract:AIM: To investigate the diagnostic value of the difference of binocular biological parameters of the anterior segment in early keratoconus.

METHODS: Retrospective case-control study. A total of 183 patients(366 eyes)who visited our hospital from March 2022 to November 2023 were included, including 107 cases(214 eyes)in the control group(patients with simple refractive error), 40 cases(80 eyes)in the subclinical keratoconus group, and 36 cases(72 eyes)in the clinical keratoconus group. All of the patients were examined by the Pentacam anterior segment analyzer to determine the inferior-superior 3 mm of the posterior corneal surface(I-S), corneal posterior elevation of the thinnest point(P.E.), maximum posterior elevation of the best fit sphere(MPE from BFS), the maximum posterior elevation of the best fit toric ellipsoid(MPE from BFTE), posterior aspherical asymmetry index(AAI), central corneal thickness(CCT), thinnest corneal thickness(TCT), pachymetric progression index average(PPIavg), Ambrósio relational thickness maximum(ARTmax), Belin/ Ambrósio enhanced ectasia display(BAD-D), and the binocular difference of each test was calculated separately for each patient. The control group was further divided according to corneal diameter: 21 cases(42 eyes)with corneal diameter <11.2 mm in group A, 54 cases(108 eyes)with 11.2 mm≤ corneal diameter ≤11.8 mm in group B, and 32 cases(64 eyes)with corneal diameter >11.8 mm in group C.

RESULTS: There was significant differences in the binocular I-S, P.E., MPE from BFS, MPE from BFTE, AAI, CCT, TCT, PPIavg, ARTmax and BAD-D between the clinical keratoconus group and the control group(P<0.05). The difference of binocular I-S, P.E., MPE from BFS, MPE from BFTE, AAI, CCT, TCT, PPIavg, and BAD-D were of high diagnostic value(AUC≥0.900), with the best diagnostic ability for P.E. and BAD-D, and an AUC as high as 0.999 and 0.995, respectively. The difference of binocular P.E. and ARTmax between the subclinical keratoconus group and the control group were statistically significant(P<0.05). The difference of binocular I-S, P.E. and BAD-D had high diagnostic value for subclinical keratoconus(AUC≥0.900). In the control group A, B and C, there were no significant difference in binocular I-S, CCT, TCT, MPE from BFS, MPE from BFTE, AAI, PPIavg and ARTmax(all P>0.05), and none of them had correlation with corneal diameter(P>0.05); however, there were statistical significant differences in binocular P.E. and BAD-D in the control group A, B and C(P=0.007, 0.003), while the P.E. differences had no correlation with corneal diameter(P=0.270), and binocular BAD-D differences were negatively correlated with corneal diameter(r=-0.230, P=0.017).

CONCLUSION: Pentacam anterior segment analyzer can accurately measure a variety of corneal biological parameters. Difference of binocular corneal I-S, P.E. and BAD-D are sensitive indexes for the early diagnosis of keratoconus. Among them, difference of binocular I-S and P.E. are less affected by corneal diameter, thus being significant for the early diagnosis of keratoconus with different cornea diameters.

Abstract:AIM: To investigate the potential causal relationship between gut microbiota(GM)and primary open-angle glaucoma(POAG)based on a two-sample Mendelian randomization(MR)analysis.

METHODS: The exposure data was derived from the Genome-Wide Association Studies(GWAS)of GM at the University of Bristol, while the outcome data for POAG was sourced from the MRC Integrative Epidemiology Unit(IEU)Open GWAS database. In this study, inverse variance weighted(IVW), MR Egger, weighted median(WM), Simple Mode, and Weighted Mode were analyzed to investigate the potential causal relationships between GM and POAG. IVW was used as the primary method for this study, and sensitivity analysis was conducted to assess the reliability of the MR analysis.

RESULTS: The IVW analysis revealed that Butyrivibrio(OR=1.170, 95%CI: 1.057-1.295, P=0.002), Howardella(OR=1.188, 95%CI: 1.043-1.355, P=0.010), and LachnospiraceaeUCG001(OR=1.229, 95%CI: 1.016-1.485, P=0.033)were correlated with the risk of POAG. Conversely, Candidatus Soleaferrea(OR=0.810, 95%CI: 0.670-0.981, P=0.031), Ruminococcustorquesgroup(OR=0.656, 95%CI: 0.453-0.950, P=0.026), and RuminococcaceaeUCG013(OR=0.770, 95%CI: 0.598-0.990, P=0.041)were protective factors for POAG. Sensitivity analysis showed that there were no heterogeneity and pleiotropy among the instrumental variables.

CONCLUSION: The MR study indicated a causal relationship between GM and POAG. Given the sight-threatening characteristic of POAG, early identification and intervention in the relative factors was significant for the prognosis of POAG.

Abstract:AIM: To analyze and screen influencing factors of diabetic patients complicated with retinopathy, and establish and validate prediction model of nomogram.

METHODS: A total of 1 252 patients from the Diabetes Complications Early Warning Dataset of the National Population Health Data Archive(PHDA)between January 2013 to January 2021 were selected and randomly divided into a modeling group(n=941)and a validation group(n=311). Univariate analysis, LASSO regression and Logistic regression analysis were used to screen out the influencing factors of diabetic retinopathy, and a nomogram prediction model was established. The receiver operating characteristic curve, Hosmer-Lemeshow test and calibration curve were used to evaluate the model. The clinical benefit was evaluated by the decision curve analysis(DCA).

RESULTS: Age, hypertension, nephropathy, systolic blood pressure(SBP), glycated hemoglobin(HbA1c), high-density lipoprotein cholesterol(HDL-C), and blood urea(BU)were the influencing factors of diabetic retinopathy. The area under the curve(AUC)of the modeling group was 0.792(95%CI: 0.763-0.821), and the AUC of the validation group was 0.769(95%CI: 0.716-0.822). The Hosmer-Lemeshow goodness of fit test and calibration curve suggested that the theoretical value of the model was in good agreement(modeling group: χ²=14.520, P=0.069; validation group: χ²=14.400, P=0.072). The DCA results showed that the threshold probabilities range was 0.09-0.89 for modeling group and 0.07-0.84 for the validation group, which suggested the clinical net benefit was higher.

CONCLUSION: This study constructed a risk prediction model including age, hypertension, nephropathy, SBP, HbA1c, HDL-C, and BU. The model has a high discrimination and consistency, and can be used to predict the risk of diabetic retinopathy in patients with diabetes.

Abstract:AIM:To observe the clinical efficacy of 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops in the treatment of dry eyes after pterygium surgery with lacrimal insufficiency.

METHODS: A total of 64 cases(64 eyes)of pterygium patients with lacrimal insufficiency were treated with pterygium resection combined with limbal stem cell transplantation, and they were given routine anti-inflammatory and infection prevention treatment postoperatively. In terms of postoperative dry eye treatment, all patients were randomly divided into two groups. The observation group was treated with 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops, and the control group was treated with sodium hyaluronate eye drops. The break-up time of tear film(BUT), fluorescein(FL), Schirmer's Ⅰ test(SⅠt), ocular surface disease index(OSDI)score, central corneal thickness(CCT)changes, adverse reactions and complications were observed and compared between the two groups at different times postoperatively.

RESULTS: Both groups of pterygium patients were accompanied with mild to moderate dry eyes with insufficient tear secretion preoperatively. At 2 wk after operation, both groups showed shorter BUT and higher FL score compared with those preoperatively(P<0.05). There was no significant difference between the two groups(P>0.05). At 4 wk after operation, BUT in the observation group was prolonged, OSDI score was decreased(both P<0.05), and FL score in both groups was decreased compared with those at with 2 wk after operation(P<0.05). The observation group was better than the control group(P<0.05). At the first day after operation, the CCT of the two groups was thicker than that preoperatively(P<0.05), and there was no significant difference in SⅠt between the two groups before and after operation(P>0.05).

CONCLUSION: In the treatment of dry eye after pterygium surgery with lacrimal insufficiency, 3% diquafosol sodium eye drops combined with sodium hyaluronate eye drops can effectively reduce the postoperative dry eye symptoms, and its clinical effect is better than that of sodium hyaluronate eye drops alone.

Abstract:AIM: To evaluate the changes in corneal epithelial thickness(CET)and corneal optical density(CD)after smart pulse technology(SPT)-assisted transepithelial photorefractive keratectomy(TPRK)and analyze their correlation.

METHODS: The prospective study included 60 patients(120 eyes)with myopia and myopic astigmatism who underwent SPT-TPRK in the ophthalmology department at the First Affiliated Hospital of Xinxiang Medical University between February and August 2023. Changes in CET and CD were evaluated preoperatively and at 1 wk, 1 and 3 mo postoperatively.

RESULTS: A total of 14 cases(28 eyes)were lost to follow-up, and 3 patients(6 eyes)with postoperative haze were excluded from this study, resulting in a final inclusion of 43 patients(86 eyes). At 1 wk after SPT-TPRK, CET had statistically significantly thickened compared to preoperative levels(P<0.05), particularly in the CET at 0-2 mm central corneal area(P<0.05). At 1 mo after SPT-TPRK, the CET at 0-2 mm area had statistically significantly decreased(P<0.05). At 3 mo after SPT-TPRK, the CET at 0-2 mm had essentially reached preoperative levels. Postoperative CD values increased, with a positive correlation between CET in the 0-2 mm area and CD in the whole 0-2 mm area(r=0.256, P<0.05), and a positive correlation between CET in the 2-5 mm area and CD in the anterior 2-6 mm area(r=0.319, P<0.05).

CONCLUSION: Corneal epithelial remodeling takes 3 mo in areas within 2 mm of the central cornea; areas with thinner CET have faster postoperative corneal epithelial remodeling and greater thickening in the early postoperative period; CD increases in the early postoperative period compared to the preoperative value, and in some areas, there is a positive correlation between CET and CD value.

Abstract:AIM: To evaluate the value of the ratio of axial length to corneal radius of curvature(AL/CR)in the diagnosis of myopia in children and adolescents.

METHODS: The refraction and ocular biometric parameters of 2 182 cases of children and adolescents(4 364 eyes)who initially visited the optometry clinic of the Second People's Hospital of Beihai from January 2022 to December 2023 were collected and analyzed.

RESULTS: The receiver operating characteristic curve(ROC curve)showed that AL/CR had a higher area under the curve(AUC=0.925, 95%CI: 0.917-0.933)in diagnosing myopia. When AL/CR was 3.053, the Youden index was the largest. As the threshold of AL/CR decreased, the sensitivity of myopia diagnosis increased, while the specificity decreased. Compared with screening myopia, the sensitivity of AL/CR=3.053 in diagnosing myopia was low, but the specificity was high, especially in the cases of hyperopia and pre-myopia.

CONCLUSION: The accuracy of AL/CR in diagnosing myopia is superior to that of axial length and average corneal curvature, with higher specificity. As the threshold of AL/CR decreases, the sensitivity of diagnosing myopia increases, but the specificity decreases. In cases of hyperopia and pre-myopia, the specificity of AL/CR in diagnosing myopia is higher than that of screening myopia.

Abstract:AIM:To observe the accuracy of infiltrating B ultrasound guided A-scan segment biometric measurement of axial length in dense cataract.

METHODS: Perspective study. A total of 86 patients(90 eyes)with dense cataract were selected from Chengdu Aier Eye Hospital from August 2020 to August 2022. There were 61 males(59 eyes)males and 25 females(31 eyes)females, with an average age of 66.49±14.55 years. The axial length(AL), anterior chamber depth(ACD)(including corneal thickness), corneal curvature(K), lens thickness(LT), central corneal thickness(CCT), and white-to-white(WTW)were measured preoperatively by contact A-scan, infiltrating B ultrasound guided segmented A-scan, and IOL Master 700, respectively. At 1 wk postoperatively, AL was retested by IOL Master 700 in aphakic mode. Furthermore, the agreements and correlations of AL obtained by the three kinds of devices were analyzed.

RESULTS:The AL measured by contact A-scan and infiltrating B ultrasound guided segmented A-scan were 23.40(22.63, 23.89)mm and 23.70(23.04, 24.25)mm, respectively, and the AL measured by IOL Master 700 at 1 wk postoperatively was 23.72(23.01, 24.27)mm. There were statistical significant difference in AL measured by the three methods(P=0.018), while there were no statistical significant difference in AL measured by infiltrating B ultrasound guided segmented A-scan and IOL Master 700(P=0.991). Bland-Altman analysis showed that there was a good agreement in AL measured by infiltrating B ultrasound guided segmented A-scan and IOL Master 700(P=0.0809). The AL measured by infiltrating B ultrasound guided segmented A-scan and IOL Master 700 was positively correlated(r_s=0.992, P<0.0001), and the AL was positively correlated between preoperative contact A-scan and postoperative IOL Master 700(r_s=0.989, P<0.0001).

CONCLUSION:For dense cataract, infiltrating B ultrasound guided A-scan segment biometric measurement, which has good correlations and agreement, is closer to the AL measured by IOL Master 700 postoperatively than that measured by contact A-scan.

Abstract:AIM: To evaluate the effect of ab-externo circumferential suture trabeculotomy(CST)on the 24 h pattern of intraocular pressure(IOP)in primary open angle glaucoma(POAG).

METHODS: This retrospective study included 18 POAG patients who had poor control of IOP from March 2021 to May 2022. The ab-externo CST was performed, and IOP was tested preoperatively and 1 a postoperatively(9:00 a.m., 12:00 a.m., 3:00 p.m., 6:00 p.m., 9:00 p.m., 12:00 p.m., 3 a.m., and 6:00 a.m.). The mean, peak, trough, and range of IOP, as well as the average diurnal-nocturnal IOP change were calculated and compared.

RESULTS: The 24 h IOP curves exhibited a decreasing trend during the diurnal period and an increasing trend during the nocturnal period, reaching a trough in the afternoon and peaking at night; the time of trough and peak IOP occurred several hours earlier compared to preoperative eyes. Postoperatively, the mean, peak, and trough IOP values were significantly lower compared to preoperative levels. The range of fluctuation showed no significant difference, while the average diurnal-nocturnal IOP change increased significantly.

CONCLUSION: CST could reduce IOP of patients with POAG, but could not change the range of IOP fluctuation. However, an increase in the average diurnal-nocturnal IOP change was observed, indicating that CST might not necessarily reduce diurnal-nocturnal IOP fluctuations.

Abstract:AIM: To explore the correlation between remnant cholesterol(RC)and anterior ischemic optic neuropathy(AION).

METHODS: A total of 80 cases of AION patients hospitalized in the department of ophthalmology of Linyi People's Hospital from January 2020 to December 2023 were selected as the observation group, and 80 cases of those who had completed health checkups in Linyi People's Hospital during the same period(without ischemic optic neuropathy and other fundus vasculopathies)were selected as the control group. The general data and biochemical indexes of the two groups were compared to evaluate the correlation between RC and AION.

RESULTS: Compared with the control group, the levels of RC, fasting blood glucose(FBG), triglyceride(TG), total cholesterol(TC), and low-density lipoprotein cholesterol(LDL-C)in patients with AION were significantly higher than those in the control group(all P<0.01). Spearman correlation analysis showed that RC was positively correlated with TG, TC, and LDL-C(all P<0.01). Logistic regression analysis showed that RC and FBG were risk factors for the development of AION. The analysis of receiver operating characteristic(ROC)curves showed that the level of RC had a better predictive value for the development of AION compared with FBG.

CONCLUSION: RC is associated with the development of AION and is a risk factor for the development of AION. Clinical standardization of the management of people with high RC values can reduce the risk of the development of AION, which is of clinical significance.

Abstract:AIM: To investigate the effect of a new type of rhinodacryocystostomy combined with fluticasone propionate on patients with chronic dacryocystitis.

METHODS: A total of 100 patients(100 eyes)with chronic dacryocystitis who admitted to our hospital between January 2021 and December 2022 were enrolled in the prospective study. The patients in the study were divided into a control group(n=50)and an observation group(n=50)based on their admission order and number. Patients in the control group were treated with novel rhinodacryocystostomy, while patients in the observation group were treated with a new type of rhinodacryocystostomy combined with fluticasone propionate. The preoperative and postoperative best corrected visual acuity(BCVA), quality of life score, and recurrence of chronic dacryocystitis were compared between the two groups of patients.

RESULTS: All patients completed the postoperative 6 mo follow-up, and the total effective rate of patients in the observation group was better than that of patients in the control group(98% vs 84%, P=0.001). There was no significant difference in preoperative and postoperative BCVA between the two groups(P>0.05). Preoperatively, there was no significant difference in the quality of life scores between the two groups of patients(P>0.05); At 6 mo postoperatively, the quality of life scores of patients in the control group, including physical function, psychological function, social function, and material life status, were lower than those in the observation group(all P<0.001). There were 9 recurrences in the control group(18%)and 1 in the observation group(2%), and there was statistical significance in the postoperative recurrence rate between the two groups(χ²=-2.739, P=0.001).

CONCLUSION: The new type of rhinodacryocystostomy combined with fluticasone propionate treatment for chronic dacryocystitis patients has a good therapeutic effect, can improve the quality of life of patients, and reduce the probability of disease recurrence.

Abstract:AIM: To investigate the effects of placement of the absorbable packing material Nasopore around the anastomosis site on postoperative re-bleeding, discomfort, and on the success rate of endoscopic dacryocystorhinostomy(En-DCR).

METHODS: Prospective randomized controlled study. A total of 101 patients(101 eyes)diagnosed with chronic dacryocystitis that underwent En-DCR in the ophthalmology department, Renmin Hospital, Hubei University of Medicine from November 2020 to October 2021 were collected. The patients were randomly divided into two groups according to whether they were packed with Nasopore at the end of operation, namely, the packed group(49 eyes)and the non-packed group(52 eyes). The postoperative follow-up was 9 mo, the degree of re-bleeding, discomfort, and postoperative success rate(including anatomical success rate and functional success rate)were compared between the two groups of patients.

RESULTS: This study included 94 patients, including 45(45 eyes)and 49(49 eyes)in packed group and non-packed group, respectively. The En-DCR was performed successfully in all patients. Postoperative re-bleeding occurred in 1 eye(2%)in the packed group, and 9 eyes(18%)in the non-packed group(P<0.05); postoperative nasal discomfort occurred in 2 cases(4%)in the packed group, and 9 cases(18%)in the non-packed group(P<0.05); The success rate of postoperative anatomical success rate was 93%(42/45)in the packed group and 88%(43/49)in the non-packed group(P>0.05). The postoperative functional success rate was 89%(40/45)in the packed group and 86%(42/49)in the non-packed group(P>0.05). Other complications such as orbital fat prolapse, cerebrospinal fluid leakage, sinusitis, visual impairment and double vision were not observed in all patients during the follow-up.

CONCLUSION: Nasal packing absorbable material Nasopore around the anastomosis at the end of En-DCR operation can reduce postoperative re-bleeding and postoperative discomfort of patients, and it has no obvious effect on the postoperative success rate.

Abstract:AIM: To analyze the causes of blindness and low vision in patients with visual disability in Yangpu District of Shanghai from 2019 to 2022.

METHODS:Cross-sectional study. A total of 1 604 patients who participated in the evaluation of visual disability in Shanghai Yangpu District Kongjiang Hospital, from April 2019 to December 2022 were selected for the study. The grade of visual disability and the main causes of blindness and low vision were determined by trained doctors.

RESULTS:A total of 804 patients with visual disabilities were identified, with 87.31% aged 60 and above. The causes of visual disability were high myopic retinopathy(30.47%), age-related macular degeneration(23.26%), glaucoma(17.04%), and diabetic retinopathy(11.07%). Glaucoma(36.96%)is the leading cause of blindness.

CONCLUSION: The majority of patients with visual disability are aged 60 years and above. More attention should be paid to the elderly population. Comprehensive prevention, treatment and rehabilitation measures should be applied in different diseases based on classification, so as to early reduce the occurrence of visual disability.

Abstract:AIM: To assess the gap between the peak of the base curve to the surface of the cornea, as well as examines the correlation between the thickness of the tear film and the fitting of the orthokeratology lens through optical coherence tomography(OCT), providing an intuitive and quantitative clinical evaluation method for the fitting of the orthokeratology lens.

METHODS: Myopia patients who fitted orthokeratology at our hospital from January to December 2023 were included. Examinations, including naked vision, slit lamp, non-contact intraocular pressure, ocular fundus, eye position, corneal diameter, corneal topography, tear film rupture time, optometry, etc., were performed on all patients before fitting. The trial lens parameter was selected according to the examination results, and fluorescein staining was performed to evaluate lens fitting state after patients adapted to wearing glasses. According to the performance of fluorescein staining, the inspected eyes are divided into three groups: lens loose group, lens fitting group, and lens tight group. In addition, the tear film thickness of three groups of subjects was measured by OCT, and the differences between the three groups of data were evaluated.

RESULTS: A total of 49 myopic patients(77 eyes)were included. The average sphere degree was -3.10±1.25 D, the average cylinder degree was -0.43(-0.75, 0)D, the average horizontal keratometry(HK)was 42.48±0.81 D, and vertical keratometry(VK)was 42.98(42.25, 43.50)D. There were 21 cases(34 eyes)in the lens fitting group, with 13 cases of bilateral eyes, 8 cases of one eye, 14 cases(22 eyes)in the lens loose group, with 8 cases of bilateral eyes, 6 cases of one eye, and 14 cases(21 eyes)in the lens tight group, with 7 cases of bilateral eyes, 7 cases of one eye. There was no statistical difference in the main basic data of the subjects in the three groups(all P>0.05). OCT showed that the tear film thickness of the lens fitting group, the lens loose group, and the lens tight group was 231.18(219.0, 243.0), 220.41(214.0, 224.3), and 249.00(241.5, 258.0)μm, respectively, and there was statistical significance in the thickness among the three groups(P<0.05).

CONCLUSION: OCT can serve as a safe and reliable method for measuring the tear film thickness, which can help evaluate the suitability of orthokeratology and provide a non-invasive, more intuitive, and quantitative evaluation method for the fitting and evaluation of orthokeratology.