Clinical characteristics of open-angle glaucoma progression with peripapillary microvasculature dropout in different locations.

OBJECTIVE: The study attempted to identify clinical characteristics associated with structural progression in open-angle glaucoma (OAG) in the presence of MvD in different locations. METHODS: A total of 181 consecutive OAG eyes (follow-up 7.3 ± 4.0 years), which demonstrated peripapillary choroidal MvD (defined as a focal capillary loss with no visible microvascular network in choroidal layer) on optical coherence tomography (OCT) angiography (OCTA), were divided based on the location of MvD. Structural progression was determined using trend-based analysis of the Guided Progression Analysis software of Cirrus OCT. RESULTS: MvD was identified in the temporal quadrant in 110 eyes (temporal MvD; 60.5 ± 12.6 years), and in the inferior quadrant in 71 eyes (inferior MvD; 60.3 ± 11.1 years). After adjusting for age, average intraocular pressure (IOP) and baseline retinal nerve fibre layer (RNFL) thickness and visual field mean deviation, inferior MvD eyes showed faster rates of thinning in the inferior RNFL (mean (95% CI); -0.833 (-1.298 to -0.367)) compared to temporal MvD eyes (-0.144 (-0.496 to 0.207)) when long-term IOP fluctuation was larger than the median value (1.7 mmHg; P = 0.022). Long-term IOP fluctuations were independently associated with inferior RNFL thinning in eyes with inferior MvD (P = 0.002) but not in eyes with temporal MvD. CONCLUSIONS: In OAG eyes, the rates of RNFL and GCIPL thinning were comparable regardless of MvD locations. However, inferior MvD is associated with faster RNFL and GCIPL thinning in the same quadrant when long-term IOP fluctuation is present. Structural progression in the presence of temporal MvD was less associated with IOP fluctuation.

Baseline intraocular pressure: an independent risk factor in severe steroid-induced ocular hypertension after intravitreal dexamethasone implant.

PURPOSE: To evaluate the baseline intraocular pressure (IOP)-related risk of severe steroid-induced ocular hypertension (SIOH). We hypothesized that the incidence and severity of SIOH may differ according to baseline IOP in patients who received intravitreal dexamethasone implants. METHODS: A total of 889 eyes treated with intravitreal dexamethasone implants and a baseline IOP of ≤ 23 mmHg were enrolled. Enrolled patients were divided into two groups: the steroid-responders (127 eyes) and the non-steroid-responders (762 eyes). The steroid-responders group was subdivided into post-injection IOP of ≥ 25, > 30, or > 35 mmHg or IOP elevation of ≥ 10 mmHg over the baseline value. The odds ratio of SIOH was calculated using univariable logistic regression analysis, and significant variables were analyzed with a multivariable model. IOP was measured before (baseline IOP) and after dexamethasone implant injection at 1 week and 1, 2, 3, 6, and 12 months. RESULTS: Although baseline IOP was significantly associated with the development of SIOH in logistic regression analysis, the results from the subgroup analysis differed. In the group with IOP elevation of ≥ 10 mmHg over the baseline, SIOH was not significantly associated with baseline IOP, but it was significantly related to higher baseline IOP in the severe SIOH group (IOP > 30 and > 35 mmHg). CONCLUSIONS: Higher baseline IOP is a risk factor for severe SIOH. Clinicians should be aware of the risk of SIOH when administering steroids intravitreally to patients with high baseline IOP (IOP > 19 mmHg).

Effect of antihypertensive medications on the risk of open-angle glaucoma.

The purpose of this study was to identify the effect of antihypertensive medication on risks of open-angle glaucoma (OAG) among patients diagnosed with hypertension (HTN). A total of 5,195 patients, who were diagnosed with HTN between January 1, 2006 and December 31, 2015, and subsequently diagnosed with OAG, were selected for analysis. For each OAG patient, 5 non-glaucomatous, hypertensive controls were matched (n = 25,975) in hypertension diagnosis date, residential area, insurance type and economic status. Antihypertensive medications were stratified into 5 types: angiotensin converting enzyme inhibitor (ACEi), angiotensin receptor blockers (ARB), calcium channel blockers (CCB), ß-blockers and diuretics. Relative risks were calculated. After adjusting for age, sex, body mass index, lifestyle, comorbidities, blood pressure (BP), follow-up duration, and use of other types of antihypertensive drugs, ARB and CCB were found to slightly increase OAG risks (RR 1.1087 (95% CI 1.0293-1.1942); 1.0694 (1.0077-1.1349), respectively). Combinations of ARB with diuretics (1.0893 (1.0349-1.1466)) and CCB (1.0548 (1.0122-1.0991)) also increased OAG risks. The risks for OAG were found to increase by antihypertensive medication use, but the effects appeared to be small. Further studies are necessary to identify the associations of increased BP, medication and therapeutic effect with OAG.

Alterations of Macular Structure in Non-Glaucomatous Subjects With Obstructive Pulmonary Function.

Purpose: The purpose of this study was to identify possible associations between obstructive pulmonary function and macular structure parameters on optical coherence tomography (OCT) and angiography in subjects without glaucomatous optic neuropathy. Methods: A total of 70 patients were prospectively enrolled from June to December 2021 as a part of All About Life Yongin-Pulmonary/Psychiatry, Rehabilitation, Eye (AALY PRE) cohort in Yongin Severance Hospital. Patients underwent intraocular pressure (IOP), visual acuity measurements, cirrus OCT, OCT angiography, and pulmonary function testing (PFT) on the same day. Subjects with glaucomatous optic nerve damage were excluded. Those whose first second of forced expiration (FEV1) to forced vital capacity (FVC) ratio was below 70% were diagnosed with obstructive pulmonary function. Vessel densities (VDs) of retinal superficial vascular plexus were compared. Results: Patients with obstructive function (n = 30) were significantly older than those with normal pulmonary function (n = 40, P < 0.001). After adjusting for age, IOP, and average ganglion cell-inner plexiform layer (GCIPL) thickness, macular VD was significantly decreased in all sectors except for the nasal sector in subjects with obstructive pulmonary function in comparison to those with normal function (P = 0.006). Multivariate regression analysis demonstrated that macular VD was linearly associated with FEV1/FVC (ß = 0.102, P = 0.031). In subjects with obstructive function, the severity of pulmonary obstruction, FEV1, was linearly associated with GCIPLT (ß = 0.302, P = 0.017). Conclusions: Obstructive pulmonary function is associated with reduced macular VD in subjects without glaucoma. Among subjects with obstructive pulmonary function, the severity of pulmonary obstruction is associated with GCIPL thickness in the macular region. Further studies are needed on the relationship between pulmonary function and macular disease.

Effect of Intraoperative Mitomycin C on the Surgical Outcomes of Ahmed Glaucoma Valve Implantation with Ciliary Sulcus Tube Placement.

PURPOSE: To evaluate the effect of intraoperative mitomycin C (MMC) on the surgical outcomes of ciliary sulcus (CS) Ahmed glaucoma valve (AGV) tube placement. METHODS: A retrospective review of medical records of 54 consecutive patients who underwent AGV implantation with tube placed in CS was performed. Consecutive cases operated without the use of intraoperative MMC from 2017 to 2019 were compared with consecutive cases operated with MMC from 2019 to 2021. Surgical failure was defined as intraocular pressure (IOP) exceeding 21 mmHg in two consecutive visits after postoperative 3 months or ≤30% IOP reduction, IOP ≤5 mmHg in two consecutive visits, or loss of light perception. Kaplan-Meier survival analysis and log-rank test were performed to compare the surgical failure rates. RESULTS: A total of 54 eyes of 54 patients were investigated. Mean follow-up period after AGV implantation was 1.4 ± 0.8 years. The MMC group showed significantly lower IOP during the 1st postoperative month (20.5 ± 8.6 mmHg vs. 15.8 ± 6.4 mmHg, p = 0.027), but the difference did not persist 6 months after the surgery (p = 0.805). The mean number of postoperative antiglaucoma medications was significantly lower in the MMC group in the 1st postoperative month (p = 0.047) but no difference was found at 6 months. No statistical difference was noted in the rates of postoperative complications. Kaplan-Meier survival analysis showed comparable survival rates between MMC group and no MMC group (p = 0.356). CONCLUSIONS: The intraoperative use of MMC significantly lowered IOP in the 1st postoperative month but did not increase 6 months success rates in patients receiving AGV tube placement in CS.

Association of trabecular meshwork height with steroid-induced ocular hypertension.

It is important to identify at-risk patients prior to administering steroid injections to prevent avoidable irreversible blindness inducted by steroid-induced ocular hypertension (SIOH). We aimed to investigate the association of SIOH following intravitreal dexamethasone implantation (OZURDEX) using anterior segment optical coherence tomography (AS-OCT). We conducted a retrospective case control study to assess the association between trabecular meshwork and SIOH. A total of 102 eyes that underwent both AS-OCT and intravitreal dexamethasone implant injection were divided into the post-steroid ocular hypertension and normal intraocular pressure groups. Ocular parameters that can contribute to intraocular pressure were measured using AS-OCT. Univariable logistic regression analysis was used to calculate the odds ratio of the SIOH and significant variables were further analyzed using a multivariable model. Trabecular meshwork (TM) height was significantly shorter in the ocular hypertension group (716.13 ± 80.55 µm) than that in the normal intraocular pressure group (784.27 ± 82.33 µm) (p < 0.001). The receiver operating characteristic curve technique analysis showed that the optimal cut-off of ≥ 802.13 µm for TM height specificity was 96.2%, and TM height with < 646.75 µm had a sensitivity of 94.70%. The odds ratio of the association was 0.990 (p = 0.001). TM height was identified as a newly observed association with SIOH. TM height can be assessed using AS-OCT, with acceptable sensitivity and specificity. Caution must be exercised while injecting steroids in patients with short TM height (especially < 646.75 µm) as it may cause SIOH and irreversible blindness.

Peripapillary choroidal microvasculature dropout is associated with poor prognosis in optic neuritis.

PURPOSE: To identify peripapillary choroidal microvasculature dropout (MvD) in eyes with optic neuritis and its association with longitudinal changes in retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIP) thicknesses following diagnosis. METHODS: A total of 48 eyes with optic neuritis was evaluated to identify the presence of peripapillary choroidal MvD, defined as a focal capillary loss with no visible microvascular network in choroidal layer, using optical coherence tomography (OCT) angiography (OCTA). Patients were divided based on the presence of MvD. OCT and standard automated perimetry (SAP) conducted at 1, 3 and 6 months follow-up were analyzed. RESULTS: MvD was identified in 20 of 48 eyes (41.7%) with optic neuritis. MvD was most commonly found in the temporal quadrant (85.0%), and peripapillary retinal vessel density in the temporal quadrant was significantly lower in eyes with MvD (P = 0.012). At 6 months follow-up, optic neuritis eyes with MvD showed significantly thinner GCIP in superior, superotemporal, inferior and inferotemporal sectors (P<0.05). No significant difference was noted in SAP parameters. The presence of MvD was significantly associated with thinner global GCIP thickness at 6 months follow-up (OR 0.909, 95% CI 0.833-0.992, P = 0.032). CONCLUSION: Optic neuritis showed peripapillary choroidal microvascular impairment in the form of MvD. MvD was associated with structural deterioration at macular GCIP. Further studies are necessary to identify the causal relationship between microvascular impairment and retinal nerve fiber layer damage in optic neuritis.

Increased risk of open-angle glaucoma in non-smoking women with obstructive pattern of spirometric tests.

To investigate differences in the prevalence of open-angle glaucoma (OAG) between different pulmonary function types. A population-based, cross-sectional analysis was conducted using Korean National Health and Nutrition Examination Surveys from 2008 to 2011. A total of 8941 subjects ≥ 40 years of age were analyzed. Chronic obstructive pulmonary disease (COPD) was defined as the ratio between first second of forced expiration (FEV1) and forced vital capacity (FVC) below 70%. The prevalence of glaucoma, as defined by the International Society of Geographical and Epidemiological Ophthalmology, was the main outcome. OAG was more prevalent in women with COPD (8.0% vs. 4.8% normal, P = 0.001) compared to women with normal pulmonary function. Intraocular pressure (IOP) of women with COPD were 13.3 (0.2) mmHg (13.9 (0.1) mmHg for normal function, P = 0.182). Never-smokers were more prevalent in women with COPD and glaucoma (92.9% vs. 52.4% normal function; P < 0.001). COPD was found to increase the risk of glaucoma in women (OR 2.077, P = 0.017) and even further in non-smoking women (OR 2.711, P = 0.003). Women with COPD showed a higher glaucoma prevalence despite similar IOP in comparison to women with normal pulmonary function. Non-smoking COPD is significantly associated with open-angle glaucoma in women.

Tube-Iris Distance and Corneal Endothelial Cell Damage Following Ahmed Glaucoma Valve Implantation.

The most significant factor for endothelial cell loss should be readily identified, since prevention is the most crucial treatment. Here, we investigate risk factors for corneal endothelial cell density (ECD) decline following Ahmed glaucoma valve (AGV) implantation and determine the optimal cut-off values. This study included 103 eyes (95 patients) with glaucoma that underwent AGV implantation between January 2006 and January 2021 at a single medical center (Severance Hospital). We conducted consecutive t-tests between two groups separated by the ECD change rate to determine the survival state of the enrolled patients. Associations were evaluated using univariable and multivariable linear regressions. Optimal cut-off values for identified risk factors were analyzed using a Cox proportional hazards model and a receiver operating characteristic (ROC) curve based on logistic regression. Mean follow-up duration was 4.09 ± 2.20 years. After implementing consecutive t-tests, only patients with an ECD change rate greater than -6.1%/year were considered to have survived. Tube-iris distance (TID) was the only statistically significant factor identified in both the univariable and multivariable linear regressions. The cut-off value determined from the consecutive Cox regression method was 0.33 mm (smallest p-value of 0.0087), and the cut-off value determined from the ROC method was 0.371 mm (area under the receiver operating characteristic curve [AUC], 0.662). Patients with short TIDs showed a better ECD prognosis following AGV surgery; we suggest optimal TID cut-off values of 0.33 mm and 0.371 mm based on the implemented Cox regression and ROC methodology, respectively.

Axial Length as a Risk Factor for Steroid-Induced Ocular Hypertension.

PURPOSE: In this study, we aimed to assess whether axial length (AXL) is a true risk factor for steroid-induced ocular hypertension (OHT). We hypothesized that the proportion of patients with steroid-induced OHT among individuals who have received intravitreal dexamethasone (DEX) injections would differ according to the AXL of their eyes. MATERIALS AND METHODS: A single-center, cross-sectional, case-control study was conducted on 467 eyes that underwent DEX implant injection owing to various retinal diseases. Intraocular pressure (IOP) was measured before the injection and 1 week and 1, 2, 3, 6, and 12 months after the injection. Enrolled patients were divided into OHT and normal IOP groups. Univariable logistic regression analysis was used to calculate odds ratios of steroid-induced OHT with significant variables being analyzed using a multivariable model. RESULTS: A longer AXL was identified as a risk factor for steroid-induced OHT via both univariable and multivariable analyses, with an odds ratio of 1.216 [95% confidence interval (CI): 1.004-1.472, p=0.0452]. The optimal cut-off value for AXL in terms of steroid-induced OHT was 23.585 mm, with an odds ratio of 2.355 (95% CI: 1.429-3.882, p=0.0008). CONCLUSION: Our findings indicate that a long AXL is a risk factor for steroid-induced OHT. Further, clinicians should be aware of steroid-induced OHT when treating patients with high myopia with steroids.

Long-term Intraocular Pressure Fluctuation Is a Risk Factor for Visual Field Progression in Advanced Glaucoma.

PRCIS: Intraocular pressure (IOP) fluctuations increase the risk of visual field progression of primary open-angle glaucoma (POAG) in the advanced stage even when IOP is maintained low on average. PURPOSE: The purpose of this study was to identify risk factors associated with the progression of visual field defect in patients with advanced POAG. MATERIALS AND METHODS: A retrospective review of medical records was conducted to identify patients who met the Hodapp-Parrish-Anderson criteria for advanced POAG. A total of 122 eyes of 122 patients had undergone IOP measurement with Goldmann applanation tonometer, standard automated perimetry, Cirrus optical coherence tomography, and fundus photography at 6-month intervals. Visual field progression was defined as the deterioration of a minimum of 3 visual field locations more than baseline at 5% levels in 4 consecutive visual fields with 24-2 SITA testing. RESULTS: Thirty-six eyes of 122 eyes (29.5%, 51.9±13.9 y old) showed visual field progression during 100.7±44.2 months of follow-up. The progression group showed greater long-term IOP fluctuations (2.6±1.4 mm Hg) than the no progression group (53.5±13.5 y; 2.0±1.0 mm Hg, P=0.008). Disc hemorrhage was detected more frequently in the progression group (40.5% vs. 17.4%, P=0.005). Multivariate Cox regression analysis revealed long-term IOP fluctuations [hazard ratio (HR)=2.567, 95% confidence interval (CI): 1.327-5.370, P=0.012] and disc hemorrhage (HR=2.351, 95% CI: 1.120-4.931, P=0.024) to be independent risk factors of visual field progression. Patients who showed both disc hemorrhage and long-term IOP fluctuations were at greater risks of progression (HR=2.675, 95% CI: 1.072-6.457, P=0.035). CONCLUSIONS: Long-term IOP fluctuations and disc hemorrhage are independent and additive risk factors of visual field progression in advanced glaucoma even at low IOPs. Patients in whom these risk factors are identified require close monitoring and vigorous treatment.

Predicting the safety zone for steroid-induced ocular hypertension induced by intravitreal dexamethasone implantation.

BACKGROUND/AIMS: This study aimed to predict the possibility of steroid-induced ocular hypertension (OHT) after intravitreal dexamethasone (DEX) implantation and to identify a proper safety zone for such injections. METHODS: A cross-sectional observational study was conducted and included 908 patient eyes that underwent DEX implant injection due to various retinal diseases. Intraocular pressure (IOP) was measured before injection, at 1 week, and at 1, 2, 3, 6 and 12 months thereafter. Eyes of enrolled patients were divided into the OHT and normal IOP groups. Univariable logistic regression analysis was used to assess significant associations between steroid-induced OHT and covariates; significant and previously reported significant variables were analysed with a multivariable model, and predictive nomograms were developed. RESULTS: Age, sex, axial length, glaucomatous eye, neovascular glaucoma, secondary glaucoma, uveitis history, hypertension, depression, diabetes mellitus and a history of previous laser-assisted in-situ keratomileusis or laser-assisted subepithelial keratectomy were significantly related to steroid-induced OHT (p<0.05). The calibration plot revealed good prediction under a predicted value of 0.4. Cut-off values for 80%, 86%, 91%, 95% and 98% sensitivity and specificity were offered for the safety zone after intravitreal DEX implantation. CONCLUSION: We developed two nomograms to predict a safety zone for intravitreal DEX implantation. These can be used to identify individuals who may be safely prescribed steroid treatments and for whom extra caution should be exercised.

Effect of red ginseng on visual function and vision-related quality of life in patients with glaucoma.

BACKGROUND: Red ginseng has been found to improve ocular perfusion and dry eye syndrome in glaucomatous eyes; however, its effects on visual function and vision-related quality of life have not been investigated. This study sought to evaluate the effects of red ginseng on visual function and vision-related quality of life in glaucoma patients using contrast sensitivity and a questionnaire. METHODS: Participants were randomly assigned to two groups in this prospective, randomized, double-blind study: in one group, red ginseng was taken first, followed by a placebo, and in the other, placebo was taken first, followed by red ginseng. We measured and compared changes in contrast sensitivity and vision-related quality of life between the two groups. Contrast sensitivity was measured using OPTEC® 6500P, and vision-related quality of life was evaluated using the 25-item National Eye Institute Visual Function Questionnaire. One-way and two-way repeated measure analyses of variance were used for the comparison. Relationships between respective changes in dry eye syndrome and contrast sensitivity were also analyzed. RESULTS: Daytime contrast sensitivity and ocular pain improved after the administration of red ginseng. Nighttime contrast sensitivity was improved in early or moderate glaucoma. Improved contrast sensitivity was not associated with improvement in dry eye syndrome. CONCLUSION: Red ginseng could improve contrast sensitivity and ocular pain in patients with glaucoma. The mechanism underlying improvement in contrast sensitivity appears to be associated with enhanced retinal perfusion or retinal ganglion cell function, but not dry eye syndrome.

Corneal endothelial cell changes and surgical results after Ahmed glaucoma valve implantation: ciliary sulcus versus anterior chamber tube placement.

We compared the changes in corneal endothelial cells and surgical outcomes after Ahmed glaucoma valve (AGV) implantation with the valve tip inserted either into ciliary sulcus (CS) or anterior chamber (AC). We retrospectively reviewed the medical records of patients treated with CS AGV (n = 24) and AC AGV (n = 38). We compared the preoperative and postoperative central corneal endothelial cell density (ECD), endothelial cell coefficient of variation (CV), best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma medications, and postoperative complications in the two groups. Both groups had similar baseline characteristics and follow-up period. At the last follow-up, the AC AGV group had significantly higher mean monthly ECD loss (17.47 ± 11.50 cells/mm2 vs. 6.40 ± 7.69 cells/mm2, p < 0.0001) and greater proportion of mean monthly ECD loss than the CS AGV group (0.84 ± 0.53 vs. 0.36 ± 0.39%, p < 0.0001). Both groups had similar mean monthly CV changes. The qualified success rates at 2 years were 83.3% and 76.3% for the CS AGV and AC AGV groups, respectively. Although similar surgical outcomes including visual acuity, IOP, number of glaucoma medications, and postoperative complications were obtained following CS AGV and AC AGV, corneal ECD loss was higher in the AC AGV group. Thus, CS AGV may be a better surgical option than AC AGV.

Glaucoma Progression after Delivery in Patients with Open-Angle Glaucoma Who Discontinued Glaucoma Medication during Pregnancy.

In this retrospective study, clinical characteristics and glaucoma progression of open-angle glaucoma (OAG) patients who discontinued intraocular pressure (IOP)-lowering medication during pregnancy were investigated. Glaucoma progression was determined using either serial visual field tests or optic disc/retinal nerve fiber layer (RNFL) photographs. Age, number of previous pregnancies, diagnosis, average IOP, IOP fluctuation, visual field mean deviation, pattern standard deviation, and RNFL thickness were examined, and their association with glaucoma progression was determined using linear regression analysis. Among 67 eyes (37 patients), 19 eyes (28.4%) exhibited glaucoma progression 13.95 ± 2.42 months after delivery. The progression group showed significantly higher mean IOP than the nonprogression group in the first, second, and third trimesters (p = 0.02, 0.001, and 0.04, respectively). The average IOP in the second, and third trimesters and IOP fluctuation during the entire pregnancy were significantly associated with glaucoma progression according to a univariate analysis (p = 0.04, 0.031, and 0.026, respectively). In conclusion, IOP elevation during pregnancy is associated with glaucoma progression after delivery in patients who had discontinued medication during pregnancy. Therefore, close monitoring of glaucoma is necessary, particularly if patients discontinue medication during pregnancy, and appropriate intervention should be considered in case of increased IOP.

Investigating the Relationship between Glaucoma Prevalence and Trabecular Meshwork Length.

Glaucoma is one of the most common causes of blindness worldwide, but the risk factors of glaucoma are yet to be fully understood. We investigated the relationship between the prevalence of glaucoma and trabecular meshwork (TM) length by comparing the mean TM length of a South Korean population with that of another ethnic population. We included 250 eyes of 125 patients who underwent anterior segment optical coherence tomography at Yonsei University Gangnam Severance Hospital between January 2015 and December 2017. We measured the distance from the scleral spur to Schwalbe's line in patients with open and closed angles and calculated the TM length using the open- and closed-angle ratios in the general population. The mean TM length of the patients in our study was 752 ± 116 µm. Considering the compensated data, the estimated true mean TM length in the Korean population was 793 ± 76 µm, which was similar to the mean TM length of a previously evaluated Hispanic population, but differed significantly from those of previously evaluated Asian (Chinese), Caucasian, and African-American populations (p < 0.05). Our results support the hypothesis that the development of glaucoma would be affected by TM length.

Effects of Hypoxic Preconditioning and Vascular Endothelial Growth Factor on the Survival of Isolated Primary Retinal Ganglion Cells.

This study aimed to investigate the effect of hypoxic preconditioning (HPC) on primary retinal ganglion cell (RGC) survival and the associated mechanism, including the role of vascular endothelial growth factor (VEGF). Retinas were separated from the enucleated eyeballs of Sprague-Dawley rats on postnatal days 1-4. RGCs were harvested using an immunopanning-magnetic separation system and maintained for 24 h in a defined medium. Hypoxic damage (0.3% O2) was inflicted on the cells using a CO2 chamber. Anti-VEGF antibody (bevacizumab) was administered to RGCs exposed to hypoxic conditions, and RGC survival rate was compared to that of non-anti-VEGF antibody-treated RGCs. HPC lasting 4 h significantly increased RGC survival rate. In the RGCs exposed to hypoxic conditions for 4 h, VEGF mRNA and protein levels were significantly increased. Treatment with high dose bevacizumab (>1 mg/mL) countered HPC-mediated RGC survival. Protein kinase B and focal adhesion kinase levels were significantly increased in 4-h hypoxia-treated RGCs. HPC showed beneficial effects on primary RGC survival. However, only specifically controlled exposure to hypoxic conditions rendered neuroprotective effects. Strong inhibition of VEGF inhibited HPC-mediated RGC survival. These results indicate that VEGF may play an essential role in promoting cell survival under hypoxic conditions.

Progression patterns of normal-tension glaucoma groups classified by hierarchical cluster analysis.

OBJECTIVES: To investigate differences in progression patterns of normal-tension glaucoma (NTG) patients in three clusters classified by hierarchical cluster analysis (HCA). MATERIALS AND METHODS: In a retrospective study, 200 eyes of NTG patients classified by HCA in 2015 who were followed up to the current date were evaluated. Peripapillary retinal nerve fibre layer (RNFL) thicknesses were measured by Cirrus HD-OCT and progression rate was calculated by trend analysis (Guided Progression Analysis [GPA]). VF progression rate was evaluated by linear regression analysis of mean deviation (MD). Progression patterns of three clusters were compared by histograms. RESULTS: In total, 153 eyes of 153 patients were followed up. Mean observation period was 5 years. RNFL reduction rate was -0.83 µm/year in cluster 1, which showed early glaucomatous damage in previous reports; -0.45 µm/year in cluster 2, which showed moderate glaucomatous damage; and -0.36 µm/year in cluster 3, which showed young and myopic glaucomatous damage. The progression pattern of cluster 3 showed a double-peak distribution; RNFL reduction rate was 0.11 µm/year in the non-progressive group and -1.07 µm/year in the progressive group. CONCLUSION: The progression patterns were different among three NTG groups that were divided by HCA. In particular, the group of young and myopic eyes showed a mixture of two different patterns.