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Purpose: Retinal ganglion cell death occurs during the glaucoma pathological process, and it is significant because of the poor regeneration capacity of retinal ganglion cells. With a constantly increasing understanding of retinal cell death mechanisms, we now know that simply blocking a specific mechanism of cell death might not prevent retinal ganglion cell death. This review aimed to summarize the mechanisms of retinal cell death in glaucoma models and discuss the caveats in restoring visual function in these studies. Methods: A literature search was done on PubMed using key words including glaucoma, ocular hypertension, retinal ganglion cell, cell death, apoptosis, necroptosis, pyroptosis, ferroptosis, autophagic cell death, and parthanatos. The literature was reviewed to summarize the information about the lethal pathways of retinal ganglion cell in the glaucoma-like animal models. Results: Based on the purpose, 100 studies were selected and discussed in this review. Conclusions: The damage to ganglion cells in glaucoma-like animals can occur via multiple lethal pathways and the molecular mechanisms are still incompletely understood. Further investigations on the crosstalk between different cell death pathways and the common upstream regulators could augment the development of novel targeting agents for the curative treatment of glaucoma. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the microvascular density of the peripapillary and parafoveal areas of the eyes with primary angle closure disease (PACD) using optical coherence tomography angiography (OCTA). Materials and methods: An observational study was conducted with 76 PACD patients (29 eyes with primary angle closure suspect, 22 eyes with primary angle closure [PAC], and 25 eyes with primary angle closure glaucoma [PACG]) and 27 control eyes. OCTA was performed for all subjects to acquire a 4.5 × 4.5 mm scanning area centered on the optic discs and a 3 × 3 mm parafoveal cubes. Peripapillary and parafoveal vessel density (VD) were compared between these four groups, and the relationship between VD values and structural and functional changes was evaluated. Results: Among all four groups, the peripapillary VD of the PACG eyes was the lowest in all six sections (all P <.01), while the parafoveal VD was lower than that of the normal group only in the average, superior, and inferior areas (all P <.05). The PAC group had lower peripapillary VD than the normal group (62.6[55.2–67.4] vs. 66.7[54.7–69.3], P =.01), while their retinal nerve fiber layer (RNFL) and ganglion cell complex thickness were not significantly different than those of the control group (all P >.05). In addition, the stages of PACD, visual field mean deviation, and RNFL thickness were shown to be predictors of the peripapillary VD in the multiple linear regression analysis. Conclusions: The PAC eyes had lower peripapillary VD than normal eyes when their RNFL and GCC thickness did not differ. This suggests that a reduction in retinal VD may occur before structural loss in PAC eyes. Retinal VD measurement may be a useful tool for the assessment of PACD. [ABSTRACT FROM AUTHOR]

Purpose: To investigate changes in peripapillary retinal vessel density after acute intraocular pressure (IOP) elevation caused by laser peripheral iridotomy (LPI) in primary angle-closure suspects (PACS) by optical coherence tomography angiography (OCTA). Materials and Methods: Ninety-seven participants with PACS were included in this cross-sectional observational study. OCTA and IOP measurement were performed at baseline and 1 h after LPI. PACS eyes were further divided into three groups according to IOP increase 1 h after LPI (group 1 = IOP elevation <5 mmHg, 42eyes; group 2 = IOP elevation ≥5 mmHg and <10 mmHg, 34 eyes; group 3 = IOP elevation ≥10 mmHg, 21eyes). The changes of vessel density in radial peripapillary capillary (RPC) and entire retina were compared among groups. Results: When all eyes were included, the vessel density of RPC and entire retina 1 h after LPI were significantly decreased compared to the baseline (RPC: 64.5 ± 7.9 vs.67.8 ± 6.8, P <.001; retina: 86.3 ± 4.6 vs.88.3 ± 3.8, P <.001). There were significant differences among the three groups in the RPC and retinal vessel density at 1 h after LPI (RPC: 67.4 ± 7.3 vs. 63.2 ± 7.6 vs. 60.9 ± 7.5, P =.003; retinal: 87.7 ± 4.0 vs. 85.8 ± 4.5 vs. 84.3 ± 5.2, P =.015). In group 2 with an increased IOP from 5 mmHg to 10 mmHg, the reduction of vessel density in the RPC was more significant than that of the entire retina (RPC vs. retina: 7.1 ± 10.0% vs. 3.0 ± 4.4%, P =.006). Conclusions: LPI-induced IOP spikes resulted in a decrease in retina vessel density with PACS eyes by OCTA. The reduction of RPC vessel density was more significant than that of the entire retina in the subgroup of IOP increase from 5 to 10 mmHg. This suggests that vessel density in RPC was more sensitive to IOP increase than that of the entire retina in the peripapillary area. [ABSTRACT FROM AUTHOR]

Purpose:The iris allows effective delivery of nutrients into the aqueous humor supplying the surrounded avascular tissues. However, possible underlying mechanisms of the iris vasculature have not been well established. This study aims to quantitatively assess the human iris vascular network, endothelial cell morphometries, and characterize endothelial junctions to better understand the properties of the iris vasculature. Materials and methods:The irises from human donor eyes were dissected and short fixed before float staining for VE-cadherin and claudin-5, f-actin and nuclei and flat-mounted for confocal imaging. The iris microvasculature was studied for its distribution and branch orders. The endothelial and nuclear morphometrics were measured for each vessel order. Characteristics of cellular junction staining and intracellular cytoskeleton were investigated. Results:The human iris vasculature was found to comprise of six orders of arteries, three orders of veins, and capillaries. The endothelial cell shape was long and narrow in all arteries, suggesting a high hemodynamic shear stress. Relatively large vessels ran radially in the superficial two-thirds of the iris, while smaller and denser vessels ran in the deepest third. Significant heterogeneity in vascular diameter, shape of the endothelia and nuclei, and the nuclear position was evident between artery, capillary and vein. Staining of junction proteins VE-cadherin and claudin-5 appeared non-uniform at the cell borders, especially in large veins. Conclusions:High rates of blood flow and special barrier properties are indicated by the morphological properties of the human iris vasculature. Detailed information of the iris vasculature combined with the inter- and intra-endothelial structure may help us further understand the physiological and pathogenic roles of the iris. [ABSTRACT FROM AUTHOR]

Purpose: To review the microbiological spectrum and antibiotic sensitivities of the pathogens that cause culture-proven endophthalmitis and to understand the status and trends of antibiotic susceptibility at a public hospital over a 10-year period. Methods: The data of 577 culture-proven endophthalmitis isolates collected between April 2004 and April 2014 were reviewed retrospectively. The antibiotic sensitivities were determined according to the criteria of the Clinical and Laboratory Standards Institute. The changes in antibiotic susceptibility over the 10 years were subjected toχ2tests for trends. Results: Among these isolates, 65% were gram-positive organisms (375), 16.6% were gram-negative organisms (96), and 18.4% were fungi (106). The predominant pathogens wereStaphylococcalspecies (Staphylococcus epidermidisin 175, other coagulase-negativeStaphylococciin 41, andStaphylococcus aureusin 54 cases), followed byBacillus cereusisolates. TheAspergillusspecies was the most frequently isolated fungus, andPseudomonas aeruginosawas the most frequently isolated gram-negative bacteria. The antibiotic susceptibilities of gram-positive bacteria were as follows: vancomycin, 97.6%; levofloxacin, 85.1%; gentamicin, 78.7%; rifampin, 77.2%; ofloxacin, 77.2%; chloramphenicol, 76.4%; and ciprofloxacin, 73.7%. The antibiotic susceptibilities of gram-negative isolates were as follows: ceftazidime, 50.5%; ciprofloxacin, 82.2%; amikacin, 81.3%; tobramycin, 80.2%; imipenem, 79.7%; and gentamicin, 78%. Over the 10-year study, there were significant changes in the antibiotic susceptibilities to the following five antibiotics: vancomycin, imipenem, penicillin G, amikacin, and trimethoprim-sulfamethoxazole (TMP-SMX). Conclusions: Vancomycin remains the most appropriate empirical antibiotic for gram-positive bacteria. The susceptibilities of the gram-negative organisms to ciprofloxacin and amikacin were greater than that to ceftazidime. Trends toward increases in the susceptibilities to the following five antibiotics were observed: vancomycin, imipenem, penicillin G, amikacin, and TMP-SMX. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate meibomian gland (MG) alterations in patients with primary chronic dacryocystitis (PCD) by in vivo confocal microscopy (IVCM), and to correlate the finding with clinical presentation. Methods: Twenty-eight eyes with the diagnosis of PCD and their contralateral unaffected eyes were studied and compared with 27 normal controls. All subjects completed an Ocular Surface Disease Index questionnaire (OSDI) and underwent slit-lamp biomicroscopy examination, tear break-up time (BUT) measurements, fluorescein staining, Schirmer test I, and an IVCM examination of the MG. IVCM parameters, including the MG acinar unit density (MGAUD), periglandular inflammatory cell density (ICD), MG acinar unit longest diameter (MGALD), and MG acinar unit shortest diameter (MGASD) and their correlation with clinical data were analyzed. Results: The mean MG expressibility scores, BUT values, and staining scores were significantly worse in eyes with PCD compared with the contralateral clinically unaffected eyes and controls ( p < 0.05). A significant decrease in MGAUD was observed in PCD eyes compared with the controls and the contralateral clinically unaffected eyes. Conversely, the mean ICD and MGASD values were significantly higher in the PCD eyes. There were no significant differences in mean MGALD value between the PCD eyes and the contralateral clinically unaffected eyes. In addition, there were significant changes in the IVCM parameters in the contralateral unaffected eyes compared with the controls, including MGAUD, ICD, MGALD, and MGASD. All IVCM parameters showed a strong, significant correlation with MG dropout grades, MG expressibility, fluorescein staining scores, and OSDI values (all p < 0.05). Conclusions: Patients with unilateral PCD demonstrated significant changes in MG as compared with the contralateral clinically unaffected eyes and controls. The MG function should be closely observed in these patients. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to determine whether patients with dry eye syndrome [DES] have more symptoms of anxiety and depression than controls without DES. Methods: In this case-control study, the sample consisted of 89 DES subjects (13 diagnosed with Sjögren's syndrome [SS]) and 73 control subjects. Each subject was diagnosed as having DES or was chosen as a control subject by an ophthalmologist. The Zung Self Rating Anxiety Scales (SAS), Zung Self Rating Depression Scales (SDS), and Ocular Surface Disease Index (OSDI) were administered to all subjects. Scores of SAS and SDS, measuring level of anxiety and depression symptoms, were compared between the DES group and the control group. Correlations with other health status measures were conducted. Results: The SAS and SDS scores of the DES group were significantly higher than the control group ( P < 0.001, P < 0.001). The prevalence of DES subjects with anxiety or depression symptoms was significantly higher than in the control group ( P = 0.003, P < 0.001). In the DES group, SAS scores were found to be correlated with OSDI and educational level. SDS scores were found to be correlated with OSDI. Neither SAS nor SDS scores were correlated with age, sex, household income, tear break up time (BUT), Schirmer Test 1 (S1T), corneal fluorescein staining (FL), or visual acuity. Conclusion: Anxiety and depression are correlated with DES, demonstrating that DES is an important public health problem that merits increased attention and research. [ABSTRACT FROM AUTHOR]