Abstract:AIM: To characterize the anti-inflammatory and anti-apoptotic effects of N-acetylcysteine (NAC) in streptozotocin (STZ)-induced diabetic rat corneal epithelium and human corneal epithelial cells (HCECs) exposed to a high-glucose environment. METHODS: HCECs were incubated in 0, 5, 50 mmol/L glucose medium, or 50 mmol/L glucose medium with NAC for 24h. Diabetes was induced in rats by intraperitoneal injection of 65 mg/kg STZ and some of these rats were topically administered NAC to corneas with 3 mice per group. We characterized receptor for advanced glycation end-products (RAGE) expression using immunofluorescence, and interleukin (IL)-1β and cleaved caspase-3 (CCAP-3) expression using immunohistochemistry. Circulating tumor necrosis factor (TNF)-α concentration was measured by ELISA and cleaved poly-ADP ribose polymerase (PARP) concentration was quantified by Western blotting. Apoptotic cells were detected using TUNEL assay and annexin V and propidium iodide staining. RESULTS: Diabetic rats had higher expression of RAGE (2.46±0.13 fold), IL-1β, and CCAP-3 in apoptotic cells of their corneas than control rats. The expression of RAGE (1.83±0.11 fold), IL-1β, and CCAP-3, and the number of apoptotic cells, were reduced by topical NAC treatment. HCECs incubated in 50 mmol/L glucose medium showed high concentrations of TNF-α (310±2.00 pg/mL) and cleaved PARP (7.43±0.56 fold), and more extensive apoptosis than cells in 50 mmol/L glucose medium. However, the addition of NAC reduced the concentrations of TNF-α (153.67±2.31 pg/mL) and cleaved PARP (5.55±0.31 fold) and the number of apoptotic cells. CONCLUSION: NAC inhibits inflammation and apoptosis in the corneas of diabetic rats and HCECs maintained in a high-glucose environment.

Abstract:AIM: To investigate whether upregulation of apoptosis-stimulating p53 protein 2 (ASPP2) expression could alleviate the development of proliferative vitreoretinopathy (PVR) in a rat model. METHODS: ASPP2-lentivirus or scrambled-lentivirus were transfected into ARPE-19 cells, followed with measurements of cell cytotoxicity by cell counting kit-8 assay. ASPP2 upregulation was confirmed by Western blotting and immunocytochemistry. Then ARPE-19 cells pretreated with ASPP2-lentivirus were intravitreally injected to Brown Norway rats to induce PVR models. PVR development and retinal function were evaluated by retinal photography and electroretinography, respectively. Finally, epithelial-mesenchymal transition as well as autophagy were investigated in rats’ retinas via Western blotting. RESULTS: Protein expression of ASPP2 was significantly upregulated by ASPP2-lentivirus transfection in ARPE-19 cells. The development and progression of PVR were impeded significantly in rats with intravitreal injection of ARPE-19 cells pretreated with ASPP2-lentivirus. Accordingly, retinal functions were less affected and PVR grades were much lower in rats with ASPP2-lentivirus compared to scrambled-lentivirus treatment. Moreover, epithelial-mesenchymal transition and autophagy markers were decreased in the retinas of rats treated with ASPP2-lentivirus. CONCLUSION: ASPP2-lentivirus transfected to ARPE-19 cells mitigates the progression of PVR in rat models, which might be partly through reduced autophagy and attenuated epithelial-mesenchymal transition. ASPP2 might stand as a new approach for PVR treatment in the future.

Abstract:AIM: To determine the effect of exosomes derived from human umbilical cord blood mesenchymal stem cells (hUCMSCs) on the expression of vascular endothelial growth factor A (VEGF-A) in human retinal vascular endothelial cells (HRECs). METHODS: Exosomes were isolated from hUCMSCs using cryogenic ultracentrifugation and characterized by transmission electron microscopy, Western blotting and nanoparticle tracking analysis. HRECs were randomly divided into a normal control group (group A), a high glucose model group (group B), a high glucose group with 25 μg/mL (group C), 50 μg/mL (group D), and 100 μg/mL exosomes (group E). Twenty-four hours after coculture, the cell proliferation rate was detected using flow cytometry, and the VEGF-A level was detected using immunofluorescence. After coculture 8, 16, and 24h, the expression levels of VEGF-A in each group were detected using PCR and Western blots. RESULTS: The characteristic morphology (membrane structured vesicles) and size (diameter between 50 and 200 nm) were observed under transmission electron microscopy. The average diameter of 122.7 nm was discovered by nanoparticle tracking analysis (NTA). The exosomal markers CD9, CD63, and HSP70 were strongly detected. The proliferation rate of the cells in group B increased after 24h of coculture. Immunofluorescence analyses revealed that the upregulation of VEGF-A expression in HRECs stimulated by high glucose could be downregulated by cocultured hUCMSC-derived exosomes (F=39.03, P<0.01). The upregulation of VEGF-A protein (group C: F=7.96; group D: F=17.29; group E: F=11.89; 8h: F=9.45; 16h: F=12.86; 24h: F=42.28, P<0.05) and mRNA (group C: F=4.137; group D: F=13.64; group E: F=22.19; 8h: F=7.253; 16h: F=16.98; 24h: F=22.62, P<0.05) in HRECs stimulated by high glucose was downregulated by cocultured hUCMSC-derived exosomes (P<0.05). CONCLUSION: hUCMSC-derived exosomes downregulate VEGF-A expression in HRECs stimulated by high glucose in time and concentration dependent manner.

Abstract:AIM: To assess the protective effect of human umbilical cord mesenchymal stem cell exosomes (hucMSC-Exs) in a diabetic rat model by using a variety of retinal bioassays. METHODS: hucMSCs were subjected to differential ultracentrifugation for the collection of exosomes, and transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) using a NanoSight analysis system and Western blotting (WB) were used to analyze the expression of surface marker proteins such as CD63, CD9 and Calnexin. Streptozotocin (STZ) was injected into the intraperitoneal cavity to establish a diabetic model. Rats were divided into a normal group, diabetic group and hucMSC-Ex group. Fundus fluorescein angiography (FFA), optical coherence tomography (OCT) and other live imaging methods were used to observe the fundus of the rats. Finally, the eyeballs of rats from each group were collected for hematoxylin-eosin (HE) staining to further analyze the retinal structure. RESULTS: Through TEM, NTA and WB, we successfully isolated hucMSC-Exs. Subsequent FFA and OCT confirmed that hucMSC-Exs effectively prevented early retinal vascular damage and thickening of the retina. Finally, HE staining of rat retinal sections revealed that exosomes effectively alleviated retinal structure disruption caused by diabetes. CONCLUSION: hucMSC-Exs have a protective effect on the retina in diabetic rat through FFA, OCT and HE staining.

Abstract:AIM: To investigate the inhibitory effect of the combined use of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and oridonin on choroidal melanoma cell lines, and to explore its underlying mechanism. METHODS: MUM-2B and C918 cells were treated with different concentrations of TRAIL and oridonin, and MTT assay used to evaluate the inhibition rate of the two compounds on cells. Then, the cell cycle distribution and apoptosis were detected by flow cytometry, and changes in apoptosis-related proteins such as death receptor 5 (DR5), a-caspase-3, and x-linked inhibitor of apoptosis protein (XIAP) were detected by Western blot. MUM-2B cells were transfected with si-DR5, which interfered with the expression of the DR5 gene. MTT and Western blot assay were used to detect cell activity and apoptosis-related proteins. RESULTS: When TRAIL and oridonin were simultaneously administered to the MUM-2B cells, the apoptosis rate was significantly higher than that by the two drugs individually. However, the effect of combined use of TRAIL and oridonin on C918 cells was not significantly different from that used alone. Cell cycle analysis showed that TRAIL and oridonin could induce G2/M arrest in MUM-2B cells. The Western blot results showed that the protein expression levels of the DR5, a-caspase-3, and BAX increased, while the expression levels of the anti-apoptosis-related proteins XIAP and BCL-2 were suppressed when TRAIL and oridonin simultaneously administered to MUM-2B cells. Interfering the expression of DR5 gene in MUM-2B cells could reverse the inhibitory effect of oridonin and TRAIL on the proliferation and apoptosis induction of MUM-2B cells. CONCLUSION: The inhibitory effects of oridonin and TRAIL on MUM-2B cells are significantly enhanced when they were administered as a combined treatment, which may ascribe to up-regulation of DR5.

Abstract:AIM: To investigate the genetic basis of autosomal recessive retinitis pigmentosa (arRP) in two consanguineous/ endogamous Pakistani families. METHODS: Whole exome sequencing (WES) was performed on genomic DNA samples of patients with arRP to identify disease causing mutations. Sanger sequencing was performed to confirm familial segregation of identified mutations, and potential pathogenicity was determined by predictions of the mutations’ functions. RESULTS: A novel homozygous frameshift mutation [NM_000440.2:c.1054delG, p. (Gln352Argfs*4); Chr5:g.149286886del (GRCh37)] in the PDE6A gene in an endogamous family and a novel homozygous splice site mutation [NM_033100.3:c.1168-1G>A, Chr10:g.85968484G>A (GRCh37)] in the CDHR1 gene in a consanguineous family were identified. The PDE6A variant p. (Gln352Argfs*4) was predicted to be deleterious or pathogenic, whilst the CDHR1 variant c.1168-1G>A was predicted to result in potential alteration of splicing. CONCLUSION: This study expands the spectrum of genetic variants for arRP in Pakistani families.

Abstract:AIM: To monitor the prognosis of patients with lacrimal gland pleomorphic adenoma (LGPA) following surgical resection within the past 10y. The factors affecting patient prognosis are analyzed and the experience of surgical treatment is summarized. METHODS: In this retrospective, comparative case series, clinical records from 109 cases of LGPA treated chiefly at the same institution between November 2009 and May 2019 were reviewed. All 109 patients underwent surgery, histopathological examination, and imaging examination. For patients who underwent surgery for the first time, LGPA could be resected completely, including tumor and capsule tissues, using a surgical approach via the eyebrow arch or double eyelid crease. RESULTS: The ratio of males to females was 1:1.60, the ages ranged from 19 to 74 years old with a mean age of 43.64±13.07 years old, and the ratio of left to right eyes was 1:1.37. A total of 109 patients underwent surgical excision and five of these received radiotherapy after malignant transformation. Of these patients, 15 were lost to follow up within the April 1, 2020 deadline and 1 was diagnosed as a recurring pathology. The 5-year recurrence rate for 86 patients who underwent initial surgery was 7.27%. Single factor analysis revealed that the course of disease, bone destruction, invasion of surrounding tissues, tumor size, capsule integrity, and expression of Ki-67 were statistically significant (P<0.05). Binomial Logistic regression analysis showed that capsule integrity was a risk factor influencing recurrence (P=0.008). CONCLUSION: LGPA has a risk of recurrence and potential for malignant transformation. Complete removal of the tumor and capsule in the initial surgery is a key factor in preventing recurrence.

Abstract:AIM: To investigate the retinal vascular network alterations in eyes of patients with pterygium. METHODS: Totally 18 left eyes from 18 female pterygium patients and 18 left eyes from 18 female healthy control subjects were enrolled. Optical coherence tomography angiography (OCTA) images were generated of the superficial retinal layer and deeper retinal layer of the macular retina for each eye. The microvascular (MIR) and macrovascular (MAR) densities were calculated and MIR, MAR, and total microvascular (TMI) density was compared in the healthy control and pterygium groups. RESULTS: In pterygium group, in the superficial retinal layer, the vascular density in superficial MIR, superior right (SR), inferior right (IR), right (R), superficial central annuli (SC)1, SC2, and SC3 decreased significantly in the macular area (P<0.05). Furthermore, the vascular density in all those decreased regions except R, was significantly and negatively correlated with the disease course (r=-0.6038 to -0.7762, P=0.0008), and the area size of pterygium (r=-0.6043 to -0.9508, P<0.05). For the deeper retinal layer, the density of deep total microvessel (DTMI), deeper MIR, SR, IR, R, DC2, and DC3 decreased significantly in macular area of pterygium patients (P<0.05). Furthermore, the vascular density in all those decreased regions was significantly and negatively correlated with the disease course (r=-0.6901 to -0.7795, P=0.0015), and the area size of pterygium (r=-0.6043 to -0.9563, P<0.05). No statistically significant differences and correlation was found in other region density (|r|<0.47, P>0.05). CONCLUSION: OCTA findings suggest that pterygium patients present with decreased retinal MIR density, and the major vascular alterations occurr mainly on the bitamporal side. The vascular density of the superficial SC1, SC2, SC3 adjacent to the foveal and deep layer of DC2, DC2 regions, significantly decreased.

Abstract:AIM: To compare perioperative parameters of one-handed rotational phacoemulsification technique (one-handed phaco-roll) with each of other two techniques, “Divide et Conquer” and femtosecond laser-assisted cataract surgery (FLACS) METHODS: In this retrospective and comparative cohort study, eyes with uncomplicated cataract (nuclear density grade 2 to 3) treated routinely with one-handed phaco-roll (n=23; Group 1) or “Divide et Conquer” (n=23; Group 2) or FLACS (n=23; Group 3) were enrolled. Intraoperative parameters including effective phaco-time (EPt), ultrasound time (USt), aspiration time, surgical time, phacoemulsification (phaco)-power, balanced salt solution (BSS) use, cumulative dissipated energy (CDE) were recorded and compared. Clinical outcomes including best corrected visual acuity (BCVA), corneal endothelial cell density (ECD), endothelial cell loss (ECL), central corneal thickness (CCT) and central macular thickness (CMT), were assessed and compared pre-operatively and at 1mo after surgery. RESULTS: Aspiration and surgical time, and BSS used were lower in Group 1 (P<0.01) than other groups. EPt, phaco-power and CDE were lower in Group 1 (P<0.05) than Group 2 but not significantly different from Group 3. In Group 1, USt was lower (P<0.05) than Group 2 but higher (P<0.05) than Group 3. BCVA improved in all groups without significant difference between Group 1 and the other ones. No significant differences regarding all post-operative morphologic outcomes (ECD, ECL, CCT, CMT) were reported. No clinical complications occurred. CONCLUSION: One-handed phaco-roll seems to be less time-consuming than “Divide et Conquer” and FLACS and less energy-consuming than “Divide et Conquer”. Furthermore, one-handed phaco-roll seems to have an equal safety profile compared to the other two techniques.

Abstract:AIM: To investigate and compare the quality of life, satisfaction, contrast sensitivity, glare, depth perception, and intraocular lens (IOL) rotation in patients who underwent trifocal toric and bifocal toric IOLs. METHODS: A total of 80 eyes of 40 patients were included in this prospective study. Twenty patients in each group were implanted with trifocal toric and bifocal toric IOL, respectively. Preoperative and postoperative 6-month measurements were recorded for both patient groups. Comprehensive anterior and posterior segment examinations, distance-intermediate-near visual acuity values and the visual function scale questionnaire results were evaluated at these examinations. Patient satisfaction, contrast sensitivity, glare, intermediate-near and distance stereopsis and IOL rotation were also evaluated. RESULTS: No significant difference was found between the groups in terms of distance and near visual acuities (P=0.269, P=0.451). Intermediate visual acuity was significantly increased in the trifocal toric group (P<0.001). The visual function scale results were increased after surgery in both groups (P=0.001 and P<0.001), with no difference determined between them (P=0.158 and P=0.691). The number of patients wearing glasses was low in both groups and there was no significant difference between the groups (P>0.05). The overall satisfaction in the trifocal toric group was significantly higher than in the bifocal toric group (P=0.03). The highest sensitivity was observed at 6 cpd spatial frequency in all patients under photopic conditions (1.80±0.24 logU, 1.74±0.20 logU). Distance-intermediate-near binocular depth perception results in both groups were higher in the trifocal toric group (P=0.02, 0.048, 0.003, respectively). Although there was no significant difference for 3 meters stereopsis, the trifocal toric group had higher depth perception (P=0.577). Mean rotation was 5.76°±3.93° in the trifocal toric group and 12°±7.1° in the bifocal toric group. CONCLUSION: Better results in the middle distance are obtained in the trifocal toric group and less IOL rotation due to digital system-coordinated surgery. Moreover, the overall satisfaction in the trifocal toric group is significantly higher than in the bifocal toric group.

Abstract:AIM: To compare the imo perimeter, a new portable head-mounted perimeter unit that enables both eyes to be examined quickly and simultaneously, with the Humphrey field analyzer (HFA) perimeter to investigate correlations and their diagnostic ability in glaucomatous eyes. METHODS: The performance of the equipment in 128 glaucomatous eyes and 40 normal eyes were tested. We investigated the correlations of mean deviation, pattern standard deviation, visual field index, and the sensitivity. RESULTS: Measurements of mean deviation (r=0.886, P<0.001), pattern standard deviation (r=0.814, P<0.001), and visual field index (r=0.871, P<0.001) in both perimeters were strongly and positively correlated. The sensitivities in the imo perimeter were 80.5% for mean deviation, 81.2% for pattern standard deviation, and 80.5% in visual field index; those in the HFA were 63.3% for mean deviation, 74.5% for pattern standard deviation, and 80.5% for visual field index. Both perimeters demonstrated high diagnostic ability. CONCLUSION: The parameters by the imo and HFA in glaucomatous eyes show strong positive correlations with favorable sensitivity, specificity, and diagnostic ability. However, the difference between imo and HFA results increases with the increase in visual field disturbance.

Abstract:AIM: To quantitatively detect aqueous levels of angiopoietin-like (ANGPTL)3, ANGPTL4, and ANGPTL6 and investigate their correlation with optical coherence tomography angiography (OCTA) findings in patients with diabetic macular edema (DME). METHODS: This cross-sectional study included 23 patients (27 eyes) with type 2 diabetes and 16 control subjects (20 eyes). All patients underwent OCTA imaging and ultra-wide field fundus photography. Diabetic patients were categorized into two groups according to the presence or absence of diabetic retinopathy (DME group, 14 patients, 16 eyes); and non-diabetic retinopathy (NDR) group, 9 patients, 11 eyes, respectively. Aqueous levels of ANGPTL3, ANGPTL4, and ANGPTL6 were assessed using suspension array technology, and foveal-centered 3×3 mm2 OCTA scans were automatically graded to determine the central, inner, and full vessel density (CVD, IVD, FVD); central, inner, and full perfusion density (CPD, IPD, FPD), foveal avascular zone (FAZ) area, FAZ perimeter, and FAZ circularity index (FAZ-CI) on superficial capillary plexuses. Additionally, central subfield thickness (CST), cube volume (CV), and cube average thickness (CAT) were measured in a model of macular cube 512×128. RESULTS: Aqueous ANGPTL3 levels were not significantly different among the three groups (P>0.05). ANGPTL4 levels were significantly higher in the DME group than the control and NDR groups (P<0.0001 and P<0.001), while ANGPTL6 levels were significantly higher in the DME group than the control group (P<0.05). In the whole cohort, the aqueous ANGPTL3 levels correlated negatively with the IVD, FVD, IPD, and FPD, and positively with the CV and CAT. The aqueous ANGPTL4 levels correlated negatively with the CVD, IVD, FVD, CPD, IPD, and FPD, and positively with the FAZ perimeter, CST, CV, and CAT. The aqueous ANGPTL6 levels correlated negatively with the IVD, FVD, IPD, FPD, FAZ-CI and positively with CST, CV, CAT. CONCLUSION: ANGPTL4 and ANGPTL6 may be associated with vascular leakage in DME and may represent good targets for DME therapy. In addition, OCTA metrics may be useful for evaluating macular ischemia in DME.

Abstract:AIM: To assist with retinal vein occlusion (RVO) screening, artificial intelligence (AI) methods based on deep learning (DL) have been developed to alleviate the pressure experienced by ophthalmologists and discover and treat RVO as early as possible. METHODS: A total of 8600 color fundus photographs (CFPs) were included for training, validation, and testing of disease recognition models and lesion segmentation models. Four disease recognition and four lesion segmentation models were established and compared. Finally, one disease recognition model and one lesion segmentation model were selected as superior. Additionally, 224 CFPs from 130 patients were included as an external test set to determine the abilities of the two selected models. RESULTS: Using the Inception-v3 model for disease identification, the mean sensitivity, specificity, and F1 for the three disease types and normal CFPs were 0.93, 0.99, and 0.95, respectively, and the mean area under the curve (AUC) was 0.99. Using the DeepLab-v3 model for lesion segmentation, the mean sensitivity, specificity, and F1 for four lesion types (abnormally dilated and tortuous blood vessels, cotton-wool spots, flame-shaped hemorrhages, and hard exudates) were 0.74, 0.97, and 0.83, respectively. CONCLUSION: DL models show good performance when recognizing RVO and identifying lesions using CFPs. Because of the increasing number of RVO patients and increasing demand for trained ophthalmologists, DL models will be helpful for diagnosing RVO early in life and reducing vision impairment.

Abstract:AIM: To investigate the safety and efficacy of sticky silicone oil (SSO) removal using a 22-gauge vein detained needle and inner limiting membrane (ILM) wrap-and-peel technique. METHODS: This retrospective consecutive case series reviewed the records of patients with a history of retinal detachment who had received silicone oil and perfluorocarbon liquid (PFCL) as intraocular tamponades. Patients were included in the analysis if they exhibited SSO remnants during silicone oil removal. The aspiration of most of the SSO remnants was performed by a 22-gauge vein detained needle. The small amounts of droplets adhered to the macula and epi-macular membrane were subsequently removed by the ILM warp-and-peel technique. The anatomical and functional outcomes, and postoperative complications were recorded. In vitro experiments were performed to simulate the formation of SSO remnants in four groups. RESULTS: Of 711 patients who underwent silicone oil removal during the study period, 9 patients exhibited SSO remnants and underwent follow-up for at least 3mo. Seven eyes (78%) underwent the ILM wrap-and-peel technique to completely remove small droplets of SSO that were glued to the macula and epi-macular membrane. No obvious complications occurred. Postoperative optical coherence tomography revealed normal retinal structure in all patients. In vitro analyses showed that balanced salt solution and prolonged vibration (for 1wk) had the strongest effects on silicone oil and PFCL compound opacities. CONCLUSION: SSO remnants could be removed in an intact manner and without complications, using a vein detained needle-assisted and ILM wrap-and-peel technique. The findings suggest that PFCL and infusion fluid should be completely removed before silicone oil injection to prevent SSO formation.

Abstract:AIM: To analyze the anatomical and functional outcomes in the inferior recurrences of rhegmatogenous retinal detachment (RRD) depending on the surgical approach. METHODS: Eighty-one eyes of 81 patients (47 males and 34 females with a mean age of 54.8±14.1y) who demonstrated at least one inferior recurrence of RRD were included in this retrospective study. All patients were categorized as having received either circular scleral buckling (SB), pars plana vitrectomy (PPV), a combination of SB and PPV (SB+PPV), PPV with retinotomy (PPV+RT), or PPV+RT and short-term postoperative perfluorocarbon liquid tamponade (PPV+RT+pPFCL). All cases were followed up until successful retinal reattachment or third recurrence. The primary outcome measures were the achievement of the surgical goal without recurrence of RRD and best-corrected visual acuity (BCVA). RESULTS: After the treatment of the first recurrence, the recurrence rate in the PPV+SB group was statistically significantly lower than that of the PPV (P=0.0012), PPV+RT (P=0.028), or PPV+RT+pPFCL (P=0.047) group. There was no statistically significant difference between PPV+SB, PPV+RT, and PPV+RT+pPFCL groups in the recurrence rate after treatment of the second recurrence (42 eyes). However, there was a statistically significant (P=0.016) trend towards a decrease of recurrence rate after PPV+RT+pPFCL. There was no statistically significant improvement of BCVA in either study group (P>0.05) after both first and second recurrence surgery. The mean time follow-up was 109.0±91.0d before the first recurrence and 210.0±186.6d between previous surgery at second recurrence. CONCLUSION: Patients with first inferior recurrence of RRD may benefit from SB as an adjunct to PPV. RT and short-term pPFCL tamponade in the second recurrence may allow better anatomical outcomes, however, without functional improvement.

Abstract:AIM: To quantify the area and density of retinal vascularity by ultra-widefield fluorescein angiography (UWFA). METHODS: In a retrospective study, UWFA images were obtained using an ultra-widefield imaging device in 42 normal eyes of 42 patients. Central and peripheral steered images were used to define the edge of retinal vasculature by a certified grader. The length from the center of the optic disc to the edge of retinal vascularity (RVL) in each quadrant and the total retinal vascular perfusion area (RVPA) were determined by the grader using OptosAdvance software. The density of retinal vascularity (RVD) was quantified in different zones of central-steered images using Image J software. RESULTS: Among 42 healthy eyes, the values for mean RVL in each quadrant were 19.007±0.781 mm (superior), 18.467±0.869 mm (inferior), 17.738±0.622 mm (nasal) and 24.241±1.336 mm (temporal). The mean RVPA was 1140.117±73.825 mm2. The mean RVD of the total retina was 4.850%±0.638%. RVD varied significantly between different retina zones (P<0.001), and significant differences existed in the RVD values for total retinal area in patients over 50 years old compared to those under 50 years old (P=0.033). No gender difference was found. CONCLUSION: The UWFA device can be a promising tool for analyzing the overall retinal vasculature and may provide a better understanding of retinal vascular morphology in normal eyes. Aging may be related to lower RVD.

Abstract:AIM: To describe the experience with half-width vertical muscles transposition (VRT) augmented with posterior fixation sutures. METHODS: The clinical charts of all patients, who underwent half-width VRT augmented with posterior fixation sutures for sixth cranial nerve palsy from January 2003 to December 2018, were retrospectively reviewed. For each patient, pre- and post-operatively, the largest measured angle was used for the calculations, usually resulting with the angle for distance, except in young infants, where measurements were made at near fixation using the Krimsky test. RESULTS: Fifteen patients met the inclusion criteria for the study, of them 9 (60.0%) had also medial rectus muscle recession at the time of surgery. Mean follow-up period was 21.4±23.2mo (range 1.5-82mo). Preoperative mean esotropia was 51.3±19.7 prism diopter (PD; range 20-90 PD). Postoperative mean deviation on final follow-up was 7.7±20.2 PD (range -40 to 35 PD; P=0.018). In all patients with preoperative abnormal head position, improvement was noted. Ten (66.7%) patients had improvement in abduction and 10 (66.7%) patients reported improvement in their diplopia, by final follow-up. The addition of medial rectus recession was correlated with a larger change in postoperative horizontal deviation compared to baseline (P=0.026). Two (13.3%) patients developed a vertical deviation in the immediate postoperative period which had resolved in one of them. CONCLUSION: Half-width VRT augmented with posterior fixation suture, with or without medial rectus muscle recession, is an effective and safe procedure for esotropia associated with sixth cranial nerve palsy. A major improvement in the angle of deviation is expected. Most patients will have improvement in their abnormal head position and diplopia.

Abstract:AIM: To assess the role of orthoptics in referring patients with orbital floor blowout fracture (OFBF) for conservative or surgical treatment and based on the results, to propose a scoring system for such decision making. METHODS: A retrospective analysis of 69 patients with OFBF was performed (35 treated conservatively, 34 surgically). The role of orthoptics in referring to surgery or conservative treatment was retrospectively evaluated, the factors with the highest significance for decision making were identified, and a scoring system proposed using Logistic regression. RESULTS: According to defined criteria, the treatment was unsuccessful in 2 (6%) surgically treated and only in one (3%) conservatively treated patient. The proposed scoring system includes the defect size and several values resulting from the orthoptic examination, the elevation of the eyebulb measured on Lancaster screen being the most significant. CONCLUSION: The study demonstrates the benefits of orthoptic examination when making decisions on conservative or surgical treatment and for diagnosing ocular motility disorder (with or without binocular diplopia) in OFBF patients. The proposed scoring system could, following verification in a prospective study, become a valuable adjunctive tool.

Abstract:AIM: To evaluate the long-term effect of foldable capsular vitreous body (FCVB) in the treatment of severe ocular rupture to provide a practical basis for clinical selection. METHODS: A total of 26 patients (26 eyes), 23 men and 3 women, with severe ocular rupture who underwent FCVB implantation between March 2018 and September 2018 were retrospectively analysed. All open ocular wounds located in zone III, with preoperative visual acuity grade IV and above (Snellen less than 4/200). The best corrected visual acuity (BCVA), intraocular pressure (IOP), cornea, anterior chamber, iris, lens, choroid, and retina were evaluated before and after the surgery. The subjective feeling and the location of FCVB were also assessed. RESULTS: The average age of the 26 patients was 36y (20-60y). Postoperative follow-up was from 10 to 14mo. At the end of follow up, BCVA was light perception (LP) in 10 cases, no light perception (NLP) in 13 cases, hand motions (HM) in 3 cases. IOP was 11±5 mm Hg. Corneal degeneration was in 3 cases and corneal endothelial dystrophy was in 7 cases. Shallow anterior chamber was in 8 cases and hyphema was in 8 cases. Organized membrane in the pupil was in 14 cases. Epiphora occurred in 3 cases. FCVB drainage tube exposed in 3 cases. All FCVBs were in their normal location and no rejection occurred. CONCLUSION: FCVB implantation is a long-term effective treatment and may provide a practical selection for severe ocular rupture.

Abstract:AIM: To predict final visual acuity and analyze significant factors influencing open globe injury prognosis. METHODS: Prediction models were built using a supervised classification algorithm from Microsoft Azure Machine Learning Studio. The best algorithm was selected to analyze the predicted final visual acuity. We retrospectively reviewed the data of 171 patients with open globe injury who visited the Pusan National University Hospital between January 2010 and July 2020. We then applied cross-validation, the permutation feature importance method, and the synthetic minority over-sampling technique to enhance tool performance. RESULTS: The two-class boosted decision tree model showed the best predictive performance. The accuracy, precision, recall, F1 score, and area under the receiver operating characteristic curve were 0.925, 0.962, 0.833, 0.893, and 0.971, respectively. To increase the efficiency and efficacy of the prognostic tool, the top 14 features were finally selected using the permutation feature importance method: (listed in the order of importance) retinal detachment, location of laceration, initial visual acuity, iris damage, surgeon, past history, size of the scleral laceration, vitreous hemorrhage, trauma characteristics, age, corneal injury, primary diagnosis, wound location, and lid laceration. CONCLUSION: Here we devise a highly accurate model to predict the final visual acuity of patients with open globe injury. This tool is useful and easily accessible to doctors and patients, reducing the socioeconomic burden. With further multicenter verification using larger datasets and external validation, we expect this model to become useful worldwide.

Abstract:AIM: To estimate the magnitude of different ocular manifestation in clinically established herpes zoster ophthalmicus (HZO) patients and assessment of the visual outcome after two months of initial examination. METHODS: An observational prospective study was conducted on 42 clinically diagnosed Tzanck smear positive cases HZO to observe the occurrence and frequency of different ocular manifestation and their visual outcome in 10-month period with 2mo follow up. Full ophthalmological examination using slit lamp, non-contact tonometry, applanation tonometry, direct and indirect ophthalmoscope were performed. RESULTS: Out of 42 patients of HZO, 33 had one or more type of ocular manifestation staring from lid skin involvement to conjunctivitis, keratitis, uveitis, increased intraocular pressure (IOP) and optic neuritis but no retinal manifestation. More number of HZO cases and ocular manifestation were found with advancement of ages. Young HZO patients were more associated with human immunodeficiency virus (HIV) infection and HIV infected people with HZO infection had more ocular manifestation. Male to female ratio was 2:1 among HZO cases but ocular manifestation occurred more among males. Female with advanced age were involved more. Lid involvement (73.81%), conjunctivitis (69.05%), and keratitis (59.52%) were most common ocular manifestation followed by anterior uveitis (30.95%) and episcleritis (11.90%). Ocular hypertension (42.86%) was associated with almost every ocular manifestation. Among the cases of more than 45 years of age, 9.52% patients acquired 6/6 vision compared to 7.14% patients at and below 45 years of age after 8wk of follow up. CONCLUSION: The visual outcomes are poor in HZO with advanced age group. Visual outcome of the affected eyes is poor than unaffected eyes. The loss of vision is mainly due to keratitis, anterior uveitis, posterior uveitis, and optic neuritis.

Abstract:AIM: To assess changed spontaneous brain activity in hyperthyroid exophthalmos (HE) patients by the amplitude of the low-frequency fluctuation (ALFF) method, and to analyze the correlation between brain activity and ALFF values in these patients. METHODS: Totally 18 HE and 18 hyperthyroid non-exophthalmos (HNE) patients were enrolled. The participants were tested by resting-state functional magnetic resonance imaging, and receiver operating characteristic (ROC) curves were generated to classify the ALFF values of the study population. Pearson’s correlation analysis was utilized to evaluate the relationship between the ALFF values obtained from different brain areas and clinical manifestations. RESULTS: Contrary to HNE patients, we observed lower ALFF values in the left calcarine fissure and surrounding cortex (LCFSC) in HE patients. In the ROC curve analysis of the LCFSC, the area under the curve reflected a high degree of accuracy. In addition, there was positive correlation between mean ALFF values of the LCFSC and the best-corrected visual acuity of the affected eyes. CONCLUSION: The study displays abnormal brain activity in LCFSC in patients with HE, which might suggest pathological mechanism of visual impairment of HE patients.

Abstract:AIM: To evaluate the clinical use of Fourier analysis of videokeratography data in the diagnosis and follow-up of keratoconus (KC). METHODS: We conducted a chart review of consecutive patients presented to our cornea clinic. A team of two experienced cornea specialists divided the patients into three groups: normal cornea, forme fruste KC (FFKC), and clinical KC. The exclusion criteria were a history of previous ocular surgery, any accompanying corneal pathology other than KC, high myopia (>6.00 diopters), amblyopia, pregnancy, breastfeeding, or any current autoimmune disease. The data of Fourier series harmonic analysis were evaluated for their diagnostic capacity using the receiver operating characteristic (ROC) curve. A binary logistic regression analysis was also conducted to construct a diagnostic model. A total of 259 eyes showed progression in the clinical KC group and underwent a combination of accelerated corneal collagen cross-linking and topography-guided customized treatment with an excimer laser. RESULTS: The study included 1262 eyes (618 normal, 530 KC, and 114 FFKC) of 1262 patients. We observed that maximum decentration (MaxDec) was almost as good as maximum keratometry (Kmax) in detecting progressive KC. The area under the curve (AUC) was 0.95 for KC [95% confidence interval (CI): 0.93-0.96] and 0.84 for FFKC (95%CI: 0.79-0.88). Higher predictive accuracy was obtained using a model combining the spherical component, MaxDec, irregularity, and regular astigmatism in the center of the cornea (AUC: 0.97; sensitivity: 89%, and specificity: 96%). CONCLUSION: Decentration, Kmax, and posterior radii of curvatures from a 3.0-mm optical zone centered on the thinnest point of the cornea provide the highest accuracy with low reproducibility of Kmax.

Abstract:AIM: To compare the clinical efficacy and safety of non-penetrating glaucoma surgery (NPGS) plus phacoemulsification (Phaco-NPGS) and NPGS-alone. METHODS: We systematically searched various databases and reviewed studies that had evaluated the effects of Phaco-NPGS or NPGS-alone for patients with glaucoma. Primary outcomes included postoperative intraocular pressure (IOP) and the number of postoperative antiglaucoma medications. Secondary outcomes were the prevalence of complications, incidence of needling or goniopuncture, and surgical success rate. RESULTS: In total, 380 and 424 eyes in NPGS-alone and Phaco-NPGS groups respectively were included. Both postoperative IOP and number of medications were significantly lowered in the Phaco-NPGS group than that in the NPDS-alone group [weighted mean difference (WMD)=-1.12, 95% confidence interval (CI): -2.11 to -0.12, P=0.03; WMD= -0.31, 95%CI: -0.53 to -0.09, P=0.006]. Moreover, Phaco-NPGS had a significantly lower prevalence of complications and postoperative procedures compared to NPGS-alone, while no significant difference existed for surgical success. CONCLUSION: Phaco-NPGS superior to NPGS-alone in the reduction of IOP and medications. Phaco-NPGS can be recommended for glaucoma patients with coexisting cataracts owing to its superior efficacy, fewer complications, and postoperative procedures.

Abstract:Retinitis pigmentosa (RP) is the most recognized inherited retinal disorder involving progressive photoreceptors degeneration which eventually causes blindness. However, the pathogenesis of RP is still unclear, making it difficult to establish satisfying treatments. Evidence have been found to support the theory that vascular dysfunction is associated with the progression of RP. Optical coherence tomography angiography (OCTA) is a newly developed technology that enables visualization as well as quantitative assessment of retinal and choroidal vasculature non-invasively. Advances in OCTA have opened a window for in-depth understanding of RP pathogenesis. Here, we propose a hypothesis of RP pathogenesis based on the current OCTA findings in RP, which includes four stages and two important key factors, vascular dysfunction and microglia activation. Further, we discuss the future animal experiments needed and how advanced OCTA technology can help to further verity the hypothesis. The final goal is to explore potential treatment options with enhanced understanding of RP pathogenesis.

Abstract:

Abstract:

Abstract: