Abstract:AIM:To investigate the distribution characteristics of retinal nerve fiber layer(RNFL)thickness and vessel density(VD)in macular area of eyes with high myopia(HM), using optical coherence tomography angiography(OCTA).

METHODS:Forty eyes in 20 patients diagnosed with HM, age 29.90±7.92 years old, with a spherical equivalent(SE)of -8.95±2.01 D, were recruited. The RNFL thickness and the VD of the superficial retinal capillary plexus(SCP), deep retinal capillary plexus, and choroidal capillary(CC)were measured by OCTA. Macular regions within a 6 mm diameter circle were divided into 9 subfields: the central subfield, and the pericentral and peripheral regions of superior, inferior, nasal, and temporal quadrants. The RNFL thickness of different subfields were compared, and their relationships with SE, axial length, and VD were analyzed.

RESULTS:In the pericentral region, the RNFL thickness of the superior quadrant was the lowest, whereas thickness was highest in the inferior quadrant(all P<0.05). In the peripheral region, the RNFL thickness of the temporal quadrant was the lowest(all P<0.05). A negative correlation was found between the RNFL thickness and SE(r=-0.356, P=0.024)in the peripheral superior subfield. The VD of SCP was positively correlated with RNFL thickness in the nasal and inferior quadrants of the pericentral region and in the superior, nasal, and inferior quadrants of the peripheral region(r=0.314, 0.408, 0.467, 0.655, and 0.737 respectively; all P<0.05), whereas the VD of CC was negatively correlated with RNFL thickness in the peripheral superior subfield(r=-0.356, P=0.024).

CONCLUSION:The RNFL of macular areas is not uniformly distributed in HM. As the SE increases, the RNFL thickness decreases in certain areas, which correlates with the VD of SCP and CC layers.

Abstract:AIM: To observe the safety and efficacy of the 25G anterior vitrectomy surgical technique via scleral flap in phacoemulsification combined with trabeculectomy for glaucoma and cataract with extremely shallow anterior chamber.

METHODS: This retrospective case review consisted of 18 eyes of 18 patients(8 males and 10 females), of those, 11 eyes had acute angle-closure glaucoma with angle-closure greater than 180 degree, and 7 eyes had lens subluxation combined with glaucoma. All 18 patients underwent phacoemulsification, intraocular lens(IOL)implantation, trabeculectomy, and anterior vitrectomy via the scleral flap in cases where conservative management techniques cannot control intraocular pressure(IOP). The main outcomes were best corrected visual acuity(BCVA), anterior chamber depth(ACD), IOP, slit-lamp microscopic examination, number of medications, fundus examination, and complications.

RESULTS: The average axial length(AL)was 21.5±0.6 mm. Mean age was 62.3±7.9 years. Mean ACD increased significantly from 0.78±0.43 mm to 2.89±0.41 mm 1wk after surgery(P<0.001). Mean IOP decreased significantly from 43.28±9.38 mmHg to 16.72±6.28 mmHg(P<0.001). No serious complications, such as endophthalmitis, retinal detachment, suprachoroidal hemorrhage, corneal decompensation, and malignant glaucoma were observed.

CONCLUSION: 25G anterior vitrectomy via scleral flap is a safe and effective technique for glaucoma and cataract with extremely shallow anterior chamber.

Abstract:AIM: To analyze the effect of ocular massage in patients after glaucoma filtering surgery.

METHODS: Databases including the CNKI, VIP Information, WanFang and CBM were electronically searched for all randomized controlled trials(RCTs)about comparing the intraocular pressure(IOP), forming efficiency of functional filtering blebs and success rate of filtering surgery between patients with and without ocular massage after receiving filtering surgery. Two reviewers independently screened literature according to the inclusion and exclusion criteria, and evaluated the included studies. Then, Meta-analysis was performed using RevMan5.3 software.

RESULTS: Totally 20 eligible studies involving 1 757 eyes of 1 750 individuals were included to investigate the effect of ocular massage in patients after glaucoma filtering surgery. Ten of the studies were related with IOP. The results of Meta-analysis showed that IOP was better controlled in patients with ocular massage in the postoperative 2wk, 1 and 3mo \〖(WMD= -0.96, 95%CI(-1.83, -0.09), P<0.05\〗, \〖WMD= -2.68, 95%CI(-3.81, -1.55), P<0.05\〗 and \〖WMD= -3.98, 95%CI(-5.00, -2.96), P<0.05\〗, respectively. Fourteen of the studies were related with the forming efficiency of functional filtering blebs. The results of Meta-analysis showed that patients with ocular massage act better in forming functional blebs \〖RR=1.33, 95%CI(1.23, 1.44), P<0.05)\〗. Nine of the studies were related with the success rate of surgery. The results of Meta-analysis showed that patients with ocular massage had higher rate of surgery success \〖(RR=1.41, 95%CI(1.28, 1.55), P<0.05)\〗.

CONCLUSION: Ocular massage can help patients after filtering surgery to control IOP more effectively and promote the formation of functional filtering blebs, so as to improve the success rate of surgery.

Abstract:AIM: To investigate if there is a gender difference in detecting global motion in adults aged 20-24 years and children aged 6-15 years, respectively.

METHODS:A total of 46 adults aged between 20-24 years, and 227 children aged between 6-15 years who were divided into five age groups(6-7 years, 8-9 years, 10-11 years, 12-13 years, and 14-15 years), participated in this study. Global motion detection was evaluated with a random dot kinematogram test, with the proportion of the dots moving at the same direction(up vs down, or left vs right)varied in each trial. The speed of each dot consisted of 1.0 and 5.0 deg/s, therefore four conditions of dots moving were examined in this study. Subjects were asked to identify the direction of the perceived global motion in a three-down-one-up staircase algorithm. The minimal proportion of signal dots moving at the same direction for global motion to be perceived is defined as the threshold. Each subject was measured five times and the mean value was recorded in each condition. Two-way analysis of variance was used for data analysis to accommodate the interaction between the two factors: age and sex maturation.

RESULTS:For signal dots moving vertically with 1.0 deg/s, the influence of gender and age on global motion detection was statistically significant(gender: F=10.533, P=0.001; age: F=8.599, P<0.001). The thresholds for adult females and 14-15 years girls were significantly higher than that in adult males(P=0.013)and 14-15 years boys(P=0.030). There was also a similar effect of gender and age for signal dots moving horizontally with 1.0 deg/s(gender: F=12.073, P=0.001; age: F=8.724, P<0.001). The thresholds for adult females and 14-15 years girls were significantly higher than that in adult males(P=0.004)and 14-15 years boys(P=0.009). For signal dots moving vertically with 5.0 deg/s, the influence of gender on global motion detection was statistically significant(F=6.826, P=0.010), while there was no difference between adults and children(F=1.085, P=0.369). The threshold for adult females was significantly higher than that in adult males(P=0.002). Finally, for signal dots moving horizontally with 5.0 deg/s, there was a similar effect as dots moving vertically with the same speed(gender: F=7.775, P=0.006; age: F=1.794, P=0.114). The thresholds for adult females and 14-15 years girls were significantly higher than that in adult males(P=0.001)and 14-15 years boys(P=0.017).

CONCLUSION: Gender difference in detecting global motion exists only in adults and children older than 14 years.

Abstract:AIM:To observe the changes of the vessel density of choriocapillaris in lens-induced myopia in guinea pigs, and to explore choroidal endothelin-1(ET-1), endothelin receptor A(ETAR)and receptor B(ETBR)expression changes and the effect of electroacupuncture.

METHODS: Fifty-four guinea pigs were randomly divided into normal control(NC), lens-induced myopia(LIM)and LIM+electroacupuncture(LIM+EA). The NC group was fed normally without intervention and the right eye in LIM group and LIM+EA group was coverd with a -6.00D lens to establish a myopia model. At 2 and 4wk, the refraction, axial length and the vessel density of choriocapillaris in groups were measured. The expression and protein content of ET-1, ETAR and ETBR mRNA in groups were detected by the real-time fluorescent quantitative PCR(quantitative polymerase chain reaction, q-PCR), enzyme-linked immunosorbent assay(ELISA)and immunohistochemistry.

RESULTS: At 2 and 4wk, compared with the the NC group, refraction and axial length in LIM group and LIM+EA group had significantly increased(all P<0.001). Compared with the LIM group, the refraction and axial length in LIM+EA group were decreased(all P<0.05). At 2 and 4wk, compared with the NC group,the vessel density of choriocapillaris was decreased(P<0.001)and the ET-1, ETAR and ETBR mRNA and protein levels in choroid were increased(all P<0.05)in LIM group. At 2 and 4wk, compared with the LIM group,the vessel density of choriocapillaris was decreased(P<0.01)and the ET-1, ETAR and ETBR mRNA and protein levels in choroid were increased in LIM+EA group.

CONCLUSION:In LIM guinea pigs, the choroidal blood flow decreased with the increased of refraction and axial length, which may affect ET-1 and its receptors through vascular shear force during the development of myopia. At the same time, electroacupuncture can improve choroidal blood flow through neuromodulation and affects the vascular shear stress to down-regulate the content of ET-1 and its receptor to delay the development of myopia.

Abstract:AIM: To investigate the effect of microRNA-373(miR-373)by targeting vascular endothelial growth factor A(VEGFA)on diabetic retinopathy(DR)rats.

METHODS: Totally 40 rats were randomly divided into control group(n=10)and DR group(n=30). The rats after successful modeling in DR group were divided into model group(n=10), miR-373 agomir group(n=10), and agomir-NC group(n=10). The right eyes vitreous cavity separately were injected with 200μL normal saline, miR-373 agomir(200nmol)and agomir-NC(200nmol)were treated once a week for 12wk. The expression levels of miR-373 and VEGFA mRNA in each group were detected by RT-qPCR. Dual luciferase experiment was used to verify the targeting relationship between miR-373 and VEGFA. Western-blot was used to detect VEGFA, Bcl-2 related X protein(Bax), b-cell lymphoma-2(Bcl-2), phosphatidylinositol 3-kinase(PI3K)and phospho phosphatidylinositol 3-kinase(p-PI3K), serine threonine protein kinase(AKT), phospho serine protein kinase(p-AKT)protein expression levels.

RESULTS: Compared with the control group, the expression levels of miR-373 and Bcl-2 protein in the retina tissue of model group and agomir-NC group were significantly decreased, and the expression levels of VEGFA mRNA, Bax, p-PI3K and p-AKT protein were significantly increased. Compared with the agomir-NC group, the expression levels of miR-373 and Bcl-2 protein in the retina tissue of miR-373 agomir group were significantly increased(all P<0.05), while the expression levels of VEGFA mRNA and protein, the Bax, p-PI3K, p-AKT protein in the retina tissue of miR-373 agomir group were significantly decreased(all P<0.05). Dual luciferase assay confirmed that VEGFA is the target gene of miR-373.

CONCLUSION: miR-373 can inhibit diabetic retinopathy by targeting VEGFA, which may be related to the inhibition of PI3K/AKT signaling pathway by miR-373.

Abstract:AIM: To investigate the role and significance of carcinoma-associated fibroblasts(CAFs)in the occurrence and development of eyelid basal cell carcinoma(BCC), and study on the biological characteristics and the expression of fibroblast activation protein(FAP)of two kinds of fibroblasts associated with eyelid BCC and normal eyelid skin fibroblasts(normal fibroblasts, NFs).

METHODS: CAFs and NFs were obtained by tissue primary cultured. The cell morphology of the 3^rd generation purified cells were observed under an inverted phase contrast microscope and identified them using their biomarker by immunohistochemistry for CK, VIM, α-SMA and FAP. Cell growth and proliferation were measured by MTT assay. The expression of FAP mRNA and protein in cells was detected by RT-qPCR and Western Blot.

RESULTS: The CAFs of the eyelid was long fusiform or spindle-shaped, with reduced cytoplasmic processes, more cytoplasmic granules, different cell sizes, disordered arrangement, overlapping growth, and loss of contact inhibition. NFs were in the form of extensive shuttle, radial arrangement, the cytoplasmic particles were rare, there was no overlapping growth phenomenon, and no contact inhibition. The proliferation rate of eyelid CAFs was faster than that of NFs. And the expression of FAP mRNA in CAFs was 3.672±0.221, which was significantly higher than that in NFs(1.034±0.024)(P<0.05). In addition, the expression level of FAP protein in CAFs was high, while NFs were not expressed(P< 0.05).

CONCLUSION: There were significant differences in the biological characteristics of CAFs and NFs, such as morphological structure, growth and the proliferation, growth factor expression and so on. It was therefore suggested that the tumor microenvironment of eyelid basal cell carcinoma had changed, and further induced the biological characteristics and function of NFs, and finally transformed into CAFs. In addition, eyelid CAFs expressed higher expression of FAP than NFs, indicating that FAP may be involved in the occurrence and development of tumor cells in tumor microenvironment, which is associated with the invasive growth of CAFs in eyelid.

Abstract:AIM: To investigate the expression of high mobility group A1(HMGA1)protein in uveal melanoma(UM)tissues, and the effect of inhibiting the expression of HMGA1 on cell proliferation and invasion.

METHODS: A total of 53 cases(53 eyes)of UM patients who underwent surgical treatment in our hospital from February 2014 to August 2019 were selected. In the same period, 34 cases(34 eyes)of normal uveal tissues removed from the eye due to trauma were selected. The expression of HMGA1 protein in tissues was detected by immunohistochemistry. The human UM cell line M23 was cultured and divided into HMGA1 downregulation group, negative control group and blank group, respectively, transfected with HMGA1 interference sequence, negative control sequence and without any treatment. The expression of HMGA1 was detected by real-time quantitative PCR. The cell proliferation ability was detected by CCK-8 method, and the cell migration and invasion abilities were detected by Transwell method.

RESULTS: The positive expression rate of HMGA1 protein in UM tissue was 77%, which was higher than that in the normal uveal tissue, which was 29%(P<0.001). Compared with the no scleral occurring infiltration, no ciliary body involving, and no extraocular growth, the positive expression rates of HMGA1 proteins in the scleral infiltration, ciliary body involving, and extraocular growth occurring tissues were increased(all P<0.05). The relative expression level of HMGA1 mRNA in cells in the HMGA1 downregulation group was lower than that in the negative control group and the blank group. Compared with the negative control group and the blank group, the absorbance OD values of cells in the HMGA1 downregulation group at 24, 48, 72 and 96h were decreased(P<0.05). The number of migrating cells and the number of invading cells in the HMGA1 downregulation group was significantly less than those in the negative control group and the blank group(P<0.05).

CONCLUSION: The positive expression rate of HMGA1 protein in UM tissue is increased. Down regulation the expression of HMGA1 in M23 cells can reduce cell proliferation and inhibit cell migration and invasion.

Abstract:AIM: To explore the effects of femtosecond laser-assisted in situ keratomileusis(FS-LASIK), topography guided LASIK(TG-LASIK)and small incision lenticule extraction(SMILE)on postoperative visual quality and higher-order aberrations(HOA)in patients with refractive errors.

METHODS: A total of 296 patients(586 eyes)with simple myopia or myopic astigmatism who were admitted to refractive center of the hospital between December 2019 and February 2020 were enrolled. Under the premise of determining surgical indications, the patients chose to undergo FS-LASIK, TG-LASIK and SMILE voluntarily. Among them, there were 95 cases(189 eyes)in FS-LASIK group, 104 cases(205 eyes)in TG-LASIK group and 97 cases(192 eyes)in SMILE group. The data such as visual acuity, diopter, corneal topography, HOA and contrast sensitivity were collected before and at 6, 12mo after surgery.

RESULTS:The uncorrected visual acuity, best corrected visual acuity, spherical equivalent and spherical equivalent refraction at 6mo after surgery were better than those before surgery(P<0.05), and there was no significant difference among different groups(P>0.05). At 6, 12mo after surgery, regularity index of corneal surface and surface asymmetry index in TG-LASIK group were significantly lower than those in SMILE group and FS-LASIK group(P<0.05), and there was no significant difference between SMILE group and FS-LASIK group(P>0.05). At 6, 12mo after surgery, total HOA, clover aberration and coma at 6mo spherical aberration in FS-LASIK group were significantly higher than those in TG-LASIK group and SMILE group(P<0.05), while the spherical aberration in the SMILE group was significantly lower than that of the other two groups(P<0.05). At 6, 12mo after surgery, contrast sensitivities with or without glare in TG-LASIK group were significantly higher than those in SMILE group and FS-LASIK group at frequencies of 12.0c/d and 18.0c/d(P<0.05).

CONCLUSION: The curative effect of FS-LASIK, TG-LASIK and SMILE are satisfactory. However, the aberration increase is less after TG-LASIK, the corneal topography is more regular, and the visual quality is higher.

Abstract:Retinal degenerative diseases such as retinitis pigmentosa and age-related macular degeneration are the main clinical blinding eye diseases with complex etiology and irreversible damage to vision. CX3CR1 is a specific receptor of the chemokine CX3CL1. Both of them participate in various physiological functions and pathological changes of the whole body through regulating the immune system of the body. In recent years, studies have pointed out that CX3CR1 regulates the activity and function of retinal microglia, which play an important role in the process of retinal degenerative diseases. In this paper, the structure and function of the chemokine receptor CX3CR1 and the role of microglia in retinal degenerative diseases were reviewed, so as to provide ideas and directions for future research and treatment of such diseases.

Abstract:Diabetic retinopathy(DR)is one of the most common chronic microvascular complications of diabetes. Due to its complex pathogenesis, DR has been an extensively international investigated topic over the past few decades. Neurodegeneration, inflammation and vascular alternately regeneration and injury could promote pathogenesis of DR. Recently more and more evidence showed that DR retinal chronic low rate could be a key factor in DR, which is a more early manifestation of DR. However, the exact molecular mechanism of its inflammation is not still clear so far. In this article, we will review the role of inflammation and its intervention mechanism in DR.

Abstract:Diabetic retinopathy(DR)is a common chronic complication of diabetes mellitus, which cause irreversible damage of microvessels in the retina. DR is a leading blindness eye disease among diabetes mellitus. The pathogenesis of DR is mainly related to oxidative stress, inflammation and neovascularization. DR patients are treated with laser photocoagulation, vitrectomy and medicine in clinical trials. The traditional Chinese medicine and Chinese herb monomers have unique efficacy in the treatment of DR, especially in retinal protection, which provides valuable supplement. The paper summarized application practice and mechanism of representative Chinese herbal formulas and Chinese herb monomers in the treatment of DR, which would provide references for the clinical treatment and new drug development of DR.

Abstract:With the rapid development of molecular biology technologies such as whole-genome testing in the past decade, non-coding RNA has been deeply explored. Circular RNA(circRNA)gradually becomes a hot topic in recent years, which plays an important role in the occurrence and development of a variety of diseases, and relevant studies have been carried out in ophthalmological diseases. This article will review the mechanism, basic research, and clinical findings of circRNA in various ophthalmic diseases, and briefly discuss the potential clinical significance of circRNA in ophthalmic diseases.

Abstract:Ocular pruritus is one of the common symptoms of ocular surface diseases. People know little about the mechanism of ocular pruritus. In clinical practice, eye drops can only be used to relieve eye discomfort. Eye itch often makes patients feel extremely painful and uncomfortable. The itch is afferent from primary neurons, mainly small-diameter unmyelinated afferent neuron fibers, whose cell bodies are located in the dorsal root ganglia or trigeminal ganglia. These neurons transmit the itch from the skin to the central nervous system. In the spinal cord, these afferent nerves synapse with secondary neurons in the dorsal horn and send signals to the brain. Pruritus sensory neurons are generally considered to be a subgroup of pain neurons. Intensity coding theory suggests that at low emissivity, neuronal activity can cause the sensation of itching. With the advancement of molecular biology and neuroscience technology, it was discovered that one of the main functions of Mrgpr(mas-related G protein-coupled receptor)protein is pruritus, and most of Mrgprs(all MrgprA, MrgprB and MrgprC subfamily members, and MrgprD)are almost exclusively expressed in specific dorsal root and trigeminal ganglion neurons. This review will introduce the mechanism and signal pathways of ocular pruritus, as well as the role of Mrgpr protein in ocular pruritus, and provide help for the treatment of ocular pruritus.

Abstract:Retinopathy of prematurity(ROP)is an avoidable and controllable oculopathy of blindness and low vision in children. Screening is the premise and a key measure for early detection, intervention and treatment. It is of great significance to reducing the blindness rate and visual impairment of children. The main of this review is to review the current situation on screening and morbidity of ROP in China, and to provide reference for preventive and treatment of ROP.

Abstract:Diabetic retinopathy(DR)is one of the common diseases that can lead to blindness, and its complicated pathogenesis has not been elucidated completely at present. Many studies have emerged that chronic inflammation plays a prominent role in the pathogenesis of DR. That many “hot spots”of inflammatory molecules, such as IL-6, IL-1β, TNF-α, and MCP-1,are involved in the part of essential mechanism of disease through complex and intertwined inflammatory pathways in the recently research. Above inflammatory factors and angiogenic factors will promote each other, especially when pathological neovascularization occur, which is greatly increasing in severity of the disease. The article made a general debate about the effect of inflammation in DR, and the relationship between inflammation and neovascularization.

Abstract:Myopic retinoschisis(MRS)is a major complication of pathological myopia. The pathogenesis of MRS is not yet fully understood and it can be the result of a number of different factors. The posterior vitreous cortex and the internal limiting membrane(ILM)are thought to play a role in the formation of the retinal splitting. In addition, retinal arteriole traction has been associated with axial length extension and the pathogenesis of MRS. The diagnosis of MRS is done by using optical coherence tomography(OCT), B-mode ultrasound and ultra-wide field fundus autofluorescence(UWF-FAF). The main treatment methods of MRS are pars plana vitrectomy(PPV)and the macular buckling technique(MB). This article reviews the pathogenesis, the course and the diagnostic methods of MRS, as well as, the treatment progress.

Abstract:Choroidal thickening spectrum diseases include pachychoroid pigment epitheliopathy(PPE)central serous chorioretinopathy(CSC), pachychoroid neovascularization(PNV)and polypoidal choroidal-vasculopathy(PCV). PPE refers to permanent abnormal increase in choroidal thickness. It is manifested as dilatation of large choroidal vessels(Haller layer)oppressing the surrounding middle vascular layer(Sattler layer)and capillary layer(Choriocapillaris layer), resulting in insufficient blood supply to the retinal pigment epithelium and causing a series of retinitis pigmentosa. The other three diseases can progress from the pachychoroid pigment epitheliopathy. The study of the pathogenic characteristics and imaging changes of choroidal thickening spectrum diseases will help to explore the diseases' pathogenesis, providing reference for early clinical diagnosis, prevention and treatment.

Abstract:Adenoid cystic carcinoma of lacrimal gland(LGACC)is the most common malignant epithelial tumor of the lacrimal gland, which is characterized by high recurrence rate, easy metastasis and poor prognosis. Although the current clinical treatment modalities for adenoid cystic carcinoma of lacrimal gland mainly include surgical resection, radiotherapy, and chemotherapy, its survival rate is still low. Therefore, it is particularly urgent to further study the pathogenesis of adenoid cystic carcinoma of the lacrimal gland and find out the biomarkers for adenoid cystic carcinoma of the lacrimal gland. In this paper, we will review the research progress in biomarkers of adenoid cystic carcinoma of the lacrimal gland.

Abstract:Graves ophthalmopathy(GO)is an autoimmune disease, mostly accompanied by orbital tissue inflammation. The practical guideline was produced by a research team of members from different scientific disciplines. The article provided a thorough interpretation of the management guidelines in GO and intended to provide direction for diagnosis of GO in daily clinical practice and improved the curative effect and medical service quantity of GO patients.

Abstract:Interleukin-17(IL-17)is an important pro-inflammatory factor in autoimmune diseases and many inflammatory diseases. Studies have shown IL-17 plays a vital role in the pathogenesis of eye disease. This paper reviews the function and mechanism of IL-17 in keratitis, dry eye, uveitis, diabetic retinopathy, and age-related macular degeneration, providing new ideas and targets for the treatment of these diseases.

Abstract:AIM: To evaluate the clinical effects of subconjunctival injection of vitamin C in the treatment of corneal ulcer by using Meta-analysis.

METHODS: Using “vitamin C” and “corneal ulcer” as keywords, the randomized controlled trials(RCT)of subconjunctival injection of vitamin C in Embase, Cochrane library, Pubmed, CNKI and Wanfang database in the treatment of corneal ulcer was searched. Relevant reference published before February 2021. The risk bias tool provided by the Cochrane cooperation scale was used to assess the risk bias of included studies of RCTs. The publication bias of the included studies were assessed by the Egger's test with Stata software. Meta-analysis was performed with RevMan 5.3.

RESULTS: A total of 32 eligible articles were included, all of which were Chinese literatures, with a total of 4 514 patients. The control group was treated with routine treatment, and the experimental group was treated with subconjunctival injection of vitamin C combined with routine treatment. The Meta-analysis showed that the experimental group was better than control group(OR=4.61, 95%CI:3.70, 5.74). The recurrence rate was lower than control group(OR=0.24, 95%CI: 0.18, 0.31). The cure time in experimental group was shorter than control group(MD= -6.29, 95%CI: -7.08, -5.51), 32 studies do not adequately report adverse drug reactions(ADR). Egger's test was performed on the total effective rate, recurrence rate and cure time. The results showed that there was publication bias in the total effective rate and cure time. Trim and fill method showed that the publication bias did not affect the results.

CONCLUSION: Subconjunctival injection of vitamin C is feasible in the treatment of corneal ulcer. The clinical effect, cure time and recurrence rate were better than routine treatment. However, due to the low intensity of the included research evidence, more multicenter, randomized double-blind clinical trials are needed to improve the evidence intensity of vitamin C in the treatment of corneal ulcer.

Abstract:AIM: To assess the changes of foveal avascular zone(FAZ)and vessel density(VD)using optical coherence tomography angiography(OCTA)in diabetic retinopathy(DR)patients.

METHODS: A systematic review of the literature was performed to examine the diagnostic used OCTA in DR to date. Six electronic databases were searched to find relevant studies. We conducted a literature search in English and Chinese databases. Two authors extracted basic data, the VD of superior capillary plexus(VD_SCP), the VD of deep capillary plexus(VD_DCP), the area and the perimeter of FAZ. We used a variety of Meta-analytic methods, including WMD forest maps, funnel plot, Begg test and sensitivity analysis, to confirm the final results.

RESULTS: Totally 24 studies recruiting 2 305 eyes were included. Patients with DR showed statistical difference in VD_SCP \〖WMD= -5.78, 95%CI (-7.67 to -3.88), P<0.05\〗, VD_DCP \〖WMD= -5.08, 95%CI(-6.49 to -3.67), P<0.05\〗, the perimeter of FAZ \〖WMD=0.57, 95%CI(0.36 to 0.78), P<0.05\〗, the area of FAZ \〖WMD=0.08, 95%CI (0.06 to 0.10), P<0.05\〗 with healthy controls.

CONCLUSION: In general, there was a trend towards a larger area and longer perimeter of FAZ in patients with DR. It can also be concluded that the VD of FAZ is higher in healthy controls. While questions remain regarding OCTA practical applicability in its present form, with continuing development and improvement of the technology, the diagnostic value of OCTA in DR is likely to become evident.

Abstract:AIM: To study the changes of the red blood cell volume distribution width(RDW)level and the correlation between them in patients with primary angle-closure glaucoma(PACG).

METHODS: Retrospective case-control study was conducted. A total of 306 PACG patients in Eye & ENT Hospital of Fudan University from February 2019 to October 2020 were selected as the case group and 126 healthy patients who received physical examination at the hospital during the same period were selected as the control group. The PACG patients were divided into three subgroups according to the mean defect of visual field(MD): mild(MD≤6dB), moderate(612dB). The detailed eye and physical examinations information of the two groups were collected from the medical data platform of Eye & ENT Hospital of Fudan University. The blood sample parameters were detected by automated hematology and biochemistry analyzers. Independent sample t-test, Chi-square test, one-way ANOVA test, Pearson correlation analyses and multiple linear regression analyses were performed in this research.

RESULTS: There was no significant difference between the PACG group and the control group in age, gender, body mass index and blood pressure(P>0.05). Based on the laboratory results, the mean RDW level was significantly higher(t=2.132, P=0.034)in the PACG group(12.64%±0.96%)than that in the control group(12.45%±0.49%). Moreover, the mean RDW level and the mean hemoglobin(HG)level was significantly lower(P<0.05)in the mild PACG subgroup than that in the moderate and severe PACG subgroups. The Pearson correlation analyses showed a positive correlation between the MD and the RDW level(r=0.141, P=0.013), a significantly positive correlation between the IOP and the RDW level(r=0.148, P=0.002), and a negative correlation between the MS and the RDW level(r=-0.154, P=0.007)in patients with PACG. After adjusting for the confounding factors, multiple linear regression analyses showed a positive association between between the MD and the RDW level in patients with PACG(β=1.405, P=0.018, 95% CI=0.240-2.570).

CONCLUSION: The RDW level of PACG patients is higer than normal. The RDW level may help to predict the PACG patients' conditions for better treatments.

Abstract:AIM: To analyze the efficacy and safety of triamcinolone acetonide(TA)combined with macular grid photocoagulation in the treatment of macular edema(ME)secondary to branch retinal vein occlusion(BRVO).

METHODS: A total of 147 patients(147 eyes)with ME secondary to BRVO treated in the hospital were enrolled between January 2016 and January 2020. They were randomly divided into observation group(73 eyes)and control group(74 eyes). The observation group was given intravitreal injection of TA and macular grid photocoagulation, while control group was given intravitreal injection of conbercept and macular grid photocoagulation. All were followed up for 6mo. Efficacy and safety indexes between the two groups were compared.

RESULTS:After treatment, best corrected visual acuity(BCVA, LogMAR)in both groups was improved. At 1mo after treatment, BCVA in observation group was better than that in control group(0.22±0.15 vs 0.27±0.13, P<0.05). At 6mo after treatment, BCVA of patients under 50 years in observation group was significantly better than that of patients under 50 years in control group(0.09±0.04 vs 0.14±0.06, P<0.05).BCVA was the best in patients with type serous retinal detachment(SRD), followed by type ME and mixed type(P<0.05). However, there was no significant difference in BCVA between any two groups in ME classifications(P>0.05). After treatment, central macular thickness(CMT)in both groups was significantly decreased. At 3mo after treatment, CMT in observation group was higher than that in control group(309.76±84.24μm vs 258.75±88.76μm, P<0.01). At 1wk, 1, 3 and 6mo after treatment, intraocular pressure in observation group was higher than that in control group(P<0.01). At 6mo after treatment, blood flow density of superficial capillary plexus(SCP)in both groups was significantly higher than that before treatment(P<0.05), but there was no significant change in blood flow density of deep capillary plexus(DCP)or the area of foveal avascular zone(FAZ)(P>0.05). The incidence of increased intraocular pressure was higher in observation group than control group(28.8% vs 14.9%), and times of intravitreal injection were fewer than those in control group(1.21±0.74 times vs 3.62±2.08 times).

CONCLUSION: TA combined with macular grid photocoagulation in the treatment of ME secondary to BRVO can maintain visual acuity at a certain level in the short term. The curative effect is comparable to that of conbercept combined with macular grid photocoagulation in terms of improving visual acuity and CMT. However, there is increased intraocular pressure, and the intraocular pressure monitoring needs to be strengthened.

Abstract:AIM: To observe the improvement of ocular hemodynamics before and after intraocular pressure(IOP)intervention in patients with non-arteritic anterior ischemic optic neuropathy(NAION).

METHODS: Retrospective case series. Totally 92 patients(92 eyes)with NAION were admitted to the Department of Ophthalmology, Xi'an Fourth Hospital from July 2012 to September 2018. Forty-six patients received only basic treatment without IOP lowering treatment as the conventional treatment group. The other 46 patients were treated with brinzolamide eye drops combined with brimonidine eye drops to lower IOP on the basis of conventional treatment, as the IOP intervention group. Before and after treatment, the blood flow rate of the ophthalmic artery and central retinal artery were measured by color Doppler ultrasound. The IOP, best corrected visual acuity(BCVA), mean visual field defect(MD), retinal nerve fiber layer thickness(RNFLT), ophthalmic artery and central retinal artery peak systolic blood velocity(PSV), end-diastolic blood velocity(EDV), pulse index(PI)and resistance index(RI)were compared.

RESULTS: Before treatment, there were no significant differences in IOP, BCVA(LogMAR), MD, RNFLT, PSV, EDV, PI and RI between the two groups(P>0.05). After 14d of treatment, IOP, BCVA(LogMAR), MD and RNFLT of the two groups were significantly improved compared with those before treatment(P<0.05), and the improvement effect of IOP intervention group was better, and the difference between the two groups was statistically significant(P<0.05). The PSV, EDV, PI of ophthalmic artery and central retinal artery in the two groups were increased compared with those before treatment, and RI was decreased compared with before treatment; and the changes of PSV, EDV, RI, PI of ophthalmic artery and PSV, EDV, RI of central retinal artery in the IOP intervention group were more significant than those in the conventional treatment group(P<0.05).

CONCLUSION: IOP intervention can significantly improve the ocular hemodynamic indexes and improve the visual acuity of patients with NAION.

Abstract:AIM: To evaluate the application effect of limbal stem cell transplantation fixed by corneal bandage lens with no suture method in primary pterygium excision surgery.

METHODS:Selected 25 patients of 50 eyes with bilateral primary pterygium who were admitted into our hospital from January 2019 to December 2019 for prospective clinical study. Group A(25 eyes)were randomly chosen with one eye of a patient fixed with corneal bandage lens with no suture; and Group B(25 eyes)were chosen with the other eye of a patient using traditional suture method. The incision healing, patient comfort, surgical complications, and postoperative recurrence were observed in both groups after postoperative follow-up for 6mo.

RESULTS: The average operating time for Group A(13.5±2.1min)was significantly less than that of Group B(26.6±7.2min). The results of postoperative follow-up in 1d, 1, 2wk, 1, 3 to 6mo showed that the discomfort such as pain, photophobia, lacrimation, foreign body sensation and itching were lower in Group A than in Group B. The discomfort disappeared in both groups after 6mo. The stability of postoperative corneal rim stem cell transplants was favorable in Group A, and the complications one and three months after surgery were less than those in Group B.

CONCLUSION: The method of banded corneal rim stem cell conjunctival transplantation combined with corneal bandage lens is an effective procedure for the treatment of primary pterygium. It is simple, convenient, safe and effective, the postoperative comfort is good, the recurrence rate is low, compared with the traditional suture method, it can shorten the operation time and effectively reduce the patient's pains.

Abstract:AIM: To investigate the therapeutic effect of 23G vitrectomy system used in children with congenital cataracts.

METHODS: From November 2017 to December 2018, 11 children(19 eyes)aged 3-8 years old with congenital cataract were recruited in the Department of Ophthalmology, the First Affiliated Hospital of Hainan Medical University. 23G vitrectomy instruments were used to enter the anterior chamber through the incision at the corneal limbus, and complete ring resection of anterior capsule, cataract aspiration, intraocular lens implantation, and ring resection of posterior capsule combined with anterior vitrectomy. The visual acuity, intraocular pressure and ocular conditions of the children were observed during 3-24mo of follow-up.

RESULTS: All the surgeries were uneventful. During the surgeries, the anterior chambers were stable, the ring resections of lens capsules were accurate, and the IOLs were implanted at the 1^st phase. The postoperative visual acuity was significantly improved compared with that before surgery. Only 1 patient had intraocular pressure higher than 25mmHg after surgery, which was controlled within the normal range after medication was given. During the follow-up period, all the children had clear corneas, no anterior chamber hemorrhage, no pupil deformation, the intraocular lens was in the center and the right position, the optic axis was transparent, and no obvious complications occurred.

CONCLUSION: The 23G vitrectomy system is safe and effective for the surgery of congenital cataract, it can achieve little trauma, accurate lens capsule resection, little postoperative reaction and few complications.

Abstract:AIM: To study the clinical changes related to dry eye and evaluate the severity of ocular surface diseases in patients with posterior chamber intraocular lens(ICL)implantation.

METHODS: Prospective study. Totally 50 eyes of 50 cases with myopia who were underwent ICL surgery from September 2019 to October 2019. Ocular surface disease index questionnaire(OSDI), fluoresceine staining of cornea tear break up time(TBUT), Schirmer Ⅰ test(SⅠt), and tear meniscus were measured before and 1wk, 1 and 3mo after surgery.

RESULTS: The scores of OSDI questionnaire and corneal staining were significantly increased at 1wk and 1mo after operation(P<0.05). There was a difference between 3mo and 1wk pastoperatve(χ²=5.267,P=0.022), and recovered to the preoperative level at about 3mo. Corneal staining scores were significantly positively correlated with OSDI questionnaire scores at all time points(r_s>0, P<0.05). TBUT decreased significantly at 1wk and 1mo after operation(P<0.05), and returned to the preoperative level 3mo after operation. There was no significant difference in the basal tear volume(SⅠt)and the height of lacrimal river in the middle of lower eyelid between before and after operation(P>0.05).

CONCLUSION: The stability of tear film on the ocular surface will be affected by ICL implantation in the early postoperative period, and the patients will have different degrees of dry eye related symptoms. OSDI questionnaire score can be used to evaluate their subjective discomfort symptoms. However, at 3mo after operation, the stability of tear film on the surface of eyes recovered to the preoperative level. The higher the positive score of corneal staining was, the more obvious the subjective discomfort was.

Abstract:AIM:To investigate the age-related cataract patients' eyelid margin and conjunctival sac bacterial distribution and eliminating effects of different antibiotic eye drops and conjunctival sac washing fluid.

METHODS: A total of 216 age-related cataract patients(216 eyes)who were hospitalized for operation in our hospital were enrolled from January 2015 to November 2015, and randomly divided into three groups(72 eyes respectively): Patients in group A were treated with 3g/L tobramycin eye drop; group B were treated with 5g/L levofloxacin eye drop and group C were treated with both two eye drops before surgery. And then each group was randomly divided into two groups: moxifloxacin group(110 eyes)and povidone iodine group(106 eyes). After the routine disinfection and before the formal start of the operation, the conjunctival sac was irrigated with 1.6g/L moxifloxacin or 5g/L povidone iodine respectively. The conjunctival sac and lid margin specimen were collected before admission without any treatment, before and after conjunctival sac irrigation for germicultures and drug susceptibility tests, at the end of operation, conjunctival sac specimen and aqueous humor were collected for germicultures and drug susceptibility tests.

RESULTS:The germiculture positive rate of eyelid margin was 86.6% and the bacterial culture positive rate of conjunctival sac was 25.0% before operation. In groups A, B and C before and after topical antibiotics application, the germiculture positive rate of eyelid margin was 86.1% and 36.1%, 84.7% and 31.9%, 88.9% and 30.6% respectively; the germiculture positive rate of conjunctival sac was 25.0% and 11.1%,26.4% and 11.1%,23.6% and 8.3% respectively. In moxifloxacin group and povidone iodine group before and after conjunctival sac irrigation, the germiculture positive rate of eyelid margin was 33.6% and 10.9%, 32.1% and 10.4% respectively; the germiculture positive rate of conjunctival sac was 10.0% and 0, 10.4% and 0 respectively.

CONCLUSION: Both 5g/L levofloxacin eye drop and 3g/L tobramycin eye drop are effective in diminishing conjunctival sac or eyelid margin bacterium before cataract sugery, the combined effect is better. Both 5g/L PVP-I and 1.6g/L moxifloxacin can be used to irrigate conjunctival sac before cataract surgery.

Abstract:AIM: To observe the safety and effect of cataract extraction combined with intraocular lens(IOL)implantation surgery in patients with abnormal morphology of corneal endothelium.

METHODS: We collected 72(90 eyes)age related cataract patients with abnormal morphology of corneal endothelium and 120(158 eyes)patients with normal morphology of corneal endothelium from January 2018 to January 2020 in our hospital. All of them measured corneal endothelial cell density(CD)>2 000cell/mm² and underwent phacoemulsification combined with IOL implantation. CD, coefficient of variation(CV), frequency of hexagonal cells(HEX), central corneal thickness(CT)were recorded at 1wk, 1, 3mo postoperatively and compared in each group.

RESULTS:There were significant differences in endothelial CD, CV, HEX and CT between the two groups 1wk and 1mo postoperative, while there were significant differences in CD and HEX between the two groups after 3mo, but there were no significant differences in CV and CT.

CONCLUSION: Endothelial damage after phacoemulsification in abnormal morphology of corneal endothelium group is comparable to that in control group, and we should pay more attention to the examination of corneal endothelium, especially the corneal endothelial cells morphology before operation and protect it during operation.

Abstract:AIM: To observe the effect of femtosecond laser-assisted cataract surgery on macula morphology.

METHODS: Retrospective study. From June 2019 to May 2020, 79 eyes of 79 cataract patients were performed cataract surgery in both groups: femtosecond laser-assisted(study group: 38 cases)and conventional phacoemulsification(control group: 41 cases). Fovea and parafoveal macular thickness of cataract patients were measured by Heidelberg OCT preoperatively and 1wk, 1mo postoperatively, and then the difference of measurement results were analyzed.

RESULTS: The retinal thickness of the fovea, the fovea area and the outer retinal ring did not show significant difference in the both groups preoperatively and postoperatively(P>0.05). Retinal thickness in the inner ring in the both groups increased significantly postoperatively, which was statistically significant(P<0.001). In the study group, the macular thickness in the inner ring increased slightly 1wk postoperatively, which was no statistical difference(P=0.057). The inner ring thickness at 1mo increased significantly compared with preoperatively and 1wk postoperatively, and the differences were statistically significant(P<0.001); In the control group, the inner macular ring was significantly thicker at 1wk and 1mo(P<0.001), and the thickness at 1mo was higher than 1wk, which was statistical difference(P=0.017). Comparison between the two groups: the thickness of macular in the inner ring in the control group was significantly higher than the study group 1wk and 1mo postoperatively, which was statistically significant(t=6.233; t=7.055, all P<0.05).

CONCLUSION: Femtosecond laser does not increase the risk of macular damage during operation. Femtosecond laser-assisted cataract surgery is less inflammation and lower macular edema in early, which is a safe surgical option.

Abstract:AIM: To evaluate the effect of Conbercept or Aflibercept on macular perfusion status in patients with diabetic macular edema(DME), and the changes in foveal avascular zone(FAZ)areas and capillary density in macular regions were measured quantitatively by optical coherence tomography angiography(OCTA).

METHODS: Twenty-six patients with DME received intravitreal injections of Conbercept or Alfibercept. The changes of FAZ areas, PERIM, AI, and macular vessel density in fovea of 300μm width(FD-300)were measured by OCTA in baseline 1, 7, and 30d after injection, and the effect of anti-VEGF drugs on blood circulation in macular area was analyzed. The best-corrected visual acuity(BCVA), central foveal thickness(CFT)were observed, the BCVA was converted to LogMAR. The changes of BCVA, CFT, FAZ, FD-300, PERIM, AI treated with anti-VEGF by methods repetitive measure analysis of variance on 1, 7, 30d after treatment were compared. Bonferroni was used to analyze the differences at different time points in pairwise comparison. Pearson correlation analysis was used to evaluate the correlation between changes in BCVA(LogMAR)and FAZ, CFT.

RESULTS: The FAZ area was 0.296±0.022mm² in baseline. After 1d drug injection, the FAZ increased to 0.339±0.024mm² (P=0.015). There was no significant difference in FAZ on the 7 and 30d after surgery(P=0.084, P=0.224). Compared with before treatment, BCVA and CFT decreased significantly, the anti-VEGF therapy was effective. The changes in PERIM, AI, and FD-300 did not reach significant level(F=2.598, P=0.059; F=0.438, P=0.726; F=0.594, P=0.621). The results of correlation analysis showed that BCVA(LogMAR)was positively correlated with FAZ and CFT(r=0.273, P=0.005; r=0.200, P=0.042)which had influence on BCVA.

CONCLUSION: With an increase in the avascular area of macular fovea was detected within 1d after intravitreal injection of anti-VEGF drug in patients with DME, and decrease in the area of avascular area in macular fovea after 1wk, accompanied by improved visual acuity. The selected appropriate index of OCTA can provide a reliable means to measure retinal circulation.

Abstract:AIM: To evaluate the outcome of scleral buckling(SB)in patients with rhegmatogenous retinal detachment(RRD)with subretinal proliferation.

METHODS: This was a retrospective clinical analysis research. Patients with RRD associated with subretinal proliferation who visited the Beijing Tongren Hospital were included in this study. From October 2016 to January 2020. There were 54 patients, including 36 males and 18 females, with the average age of 24.92±11.99 years. The retinal detachment range <1, 1-2 and >2 quadrants were 12, 25 and 17 eyes, respectively. The macula was involved in 47 eyes. Subretinal proliferation range <1, 1-2 and >2 quadrants were 26, 23 and 5 eyes, respectively. The average Logarithm of the minimum angle of resolution(LogMAR)best corrected visual acuity(BCVA)was 1.21±0.77, all patients were treated with SB under general anesthesia and the anatomical retinal reattachment, visual acuity and complications were observed.

RESULTS: The retina was reattached in 52 eyes(96%), and 2 eyes(4%)needed pars plana vitrectomy for retinal redetachment. The mean follow wp was 19.17±11.15mo. The BCVA improved from 1.21±0.77 LogMAR before surgery to 0.61±0.40 LogMAR after surgery(P<0.01). No serious complications occurred.

CONCLUSION: Under the circumstance of correct selection of indications, SB was highly successful in eyes with RRD associated with subretinal proliferation.

Abstract:AIM:To analyze the treatment of orbital Trapdoor fracture in children and the application of absorbable plate in surgery, so as to accumulate experience for clinical diagnosis and treatment.

METHODS: Retrospective analysis of 55 cases(55 eyes)orbital Trapdoor fractures in children. The fracture site was simple orbital floor fracture. All patients were approached by palpebral conjunctiva of lower eyelid. During operations, the embedded extraocular muscles and orbital tissues were returned. A resorbable implant was implanted into the orbit after trimming to proper sizes and shaped according to the fracture defect range. The therapeutic effect was evaluated by preoperative and postoperative ocular examination and orbital CT scan. Repeated measure analysis of variance was used to compare the differences of postoperative outcome evaluation indexes among patients with different operation timing.

RESULTS: No serious complications happened during and after surgeries in all patients. The postoperative CT scan showed that the fractures had good anatomical restoration. After the operation, diplopia and limitation of extraocular muscle movement(EOM)recovered obviously. The earlier the operation performed after the injury, the better the postoperative recovery effect was. At the same time, the resorbable implant could repair orbital Trapdoor fracture in children well. It serves as a better material of orbital fracture repairment.

CONCLUSION: Operation is an effective method to treat orbital Trapdoor fracture in children, and should be performed as soon as possible after injury. The resorbable implant is a good orbital repair material.

Abstract:AIM: To explore the clinical effect and safety of deep lateral wall combined with medial wall orbital decompression in the treatment of thyroid associated ophthalmopathy(TAO).

METHODS: Totally 17 patients with TAO in our department from January 2019 to May 2020 were included. All patients underwent deep lateral wall combined with medial wall orbital decompression under general anesthesia, the visual acuity, recovery of exposure keratitis, exophthalmos, intraocular pressure and complications were compared before and after operation.

RESULTS: Eight patients(9 eyes)with TAO and dysthyroid optic neuropathy(DON)were included in the study. The best corrected visual acuity averaged 0.78±0.15 preoperatively and 0.36±0.12 1mo postoperatively, which was statistically significant(P<0.01)compared with the preoperative visual acuity, 0.38±0.12 at 6mo after surgery, which was not statistically different from that at 1mo after surgery(P=0.594). The mean preoperative proptosis was 23.75±2.55mm and the mean postoperative proptosis was 14.85±1.53mm at 1mo, which was statistically significant compared with the preoperative proptosis(P<0.01), proptosis was on average 14.60±1.64mm at 6mo after surgery and remained generally stable(P=0.658)from 1mo before surgery. The intraocular pressure of the patients was 25.56±3.23mmHg preoperatively and 18.42±2.35mmHg 1mo postoperatively, which was statistically significant compared with the preoperative value(P<0.01), and the intraocular pressure of the patients was reduced to 15.82±2.57mmHg at the 6mo postoperative follow-up, which was statistically significant compared with the intraocular pressure of the patients 1mo postoperatively(P<0.01). There were 6 eyes of 6 patients with exposure keratitis preoperatively, 4 eyes improved and 2 eyes were cured in the 1mo postoperative, and all 6 eyes were cured 6mo postoperatively. Postoperatively, the diplopia of the patients all decreased to various degrees, and there were some patients whose diplopia symptoms continued to improve 6mo thereafter without other serious complications.

CONCLUSION: Deep lateral wall combined with medial wall orbital decompression can effectively improve the proptosis and also have a good effect on severe complications such as DON and exposure keratitis with few complications, so deep lateral wall combined with medial wall orbital decompression is an effective surgical procedure in the treatment of severe TAO.

Abstract:AIM:To evaluate the mitomycin-C(MMC)0.02% efficacy in preventing haze after trans-epithelial photorefractive keratectomy(Trans-PRK)in the treatment of the high myopia.

METHODS: Retrospective case series. Trans-PRK were performed on 142 eyes with a preoperative spherical equivalent. They were divided into with 0.02% MMC(MMC group)and without MMC(control)groups. In MMC group there were 94 eyes with MMC 0.02%; in control group there were 48 eyes. Patients were treated with an intraoperative application of MMC 0.02% for 30-45s depending on refractive error in MMC group. After surgery, fluorometholone 0.1% eye drops were used for 4mo in all groups. The mean follow-up time was 6mo. The regression trees were used to analyse the relationship between different related factors and haze.

RESULTS:Haze was quantified with Fantes. Incidence of haze was 8.5% eyes in MMC group and 33.3% in without MMC group(P=0.001). In the regression trees, optical zone and ablation depth MAX were related to haze(P<0.01). It was possibility induce haze when optical zone is ≤5.6mm. When optical zone is >5.6mm, ablation depth MAX becomes the main factor for haze.

CONCLUSION: The design of optical zone and ablation depth MAX in Trans-PRK should be considered for the treatment of the high myopia with thin cornea and abnormal corneal morphology. MMC 0.02% was effective in preventing haze after Trans-PRK in the treatment of the high myopia.

Abstract:AIM: To present the visual quality and refractive outcomes obtained in small incision lenticule extraction(SMILE)refractive surgeries, and observe the follow-up of patients over 1a period.

METHODS: Retrospective comparative analysis of 85 patients(85 eyes)were treated with SMILE between July and December 2019. Pre- and postoperative uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), spherical equivalent refraction(SE)were all observed, to evaluate the efficacy, safety and predictability after SMILE refractive surgery. Total corneal higher-order aberrations(HOAs), modulation transfer function cut-off(MTF_cutoff), strehl ratio(SR), and objective scattering index(OSI)were evaluated.

RESULTS: One year after SMILE refractive surgery, the efficacy index was 1.08, 84 eyes(99%)reached an UDVA as or over CDVA preoperatively, 22 eyes(26%)gained one line of CDVA than preoperatively. The safety index was 1.04, 59 eyes(69%)of the treated eyes had an unchanged CDVA postoperatively, 24 eyes(28%)gained one line of CDVA, 2 eyes(2%)gained two lines of CDVA. 85 eyes(100%)were all within ±0.50D. The pre-correction is highly related with the actual correction of SE(Y=0.9949X-0.0033; R²=0.9977). HOA, spherical aberration and coma were increased under pupil diameters of 6mm(all P<0.001). Both MTF_cutoff and SR were higher than that of SMILE preoperatively(P<0.05).

CONCLUSION: SMILE demonstrated to be safe, effective, and predictable in the treatment of myopia and myopic astigmatism, and good accuracy in correcting medium and low astigmatism. The post-quality of retinal image is better than that of SMILE preoperatively.