Peripapillary and fovea avascular zone optical coherence tomography angiography parameters in exfoliation glaucoma versus primary open-angle glaucoma versus healthy eyes.

Purpose: To examine the differences in the peripapillary vascular parameters and foveal-avascular-zone (FAZ) vascularity parameters between primary open-angle-glaucoma (POAG) patients versus exfoliation-glaucoma (XFG) patients versus healthy subjects. Methods: This is cross-sectional study and a comparative clinical study. POAG and XFG patients and healthy subjects underwent a comprehensive ophthalmic examination, including visual field optical coherence tomography (OCT) and OCT angiography (OCTA) of the optic disc and FAZ. Differences in peripapillary vessel density (VD), perfusion density (PD), and FAZ area and circularity were examined between all groups, as well as correlations between clinical parameters and vascularity parameters for each glaucoma group. Results: A total of 109 subjects (one eye for each patient) were analyzed, including 45 with POAG, 30 with XFG, and 34 controls. The average peripapillary VDs were the lowest among the XFG patients and the highest among the controls (P < 0.05, ANOVA). The average peripapillary PD of the central ring was the lowest in the XFG group and the highest in the control group (P = 0.02, ANOVA). A significant negative correlation was found between the average peripapillary VDs and PDs of the inner ring and full ring and disease severity of the POAG patients. There was a significant positive correlation between the average peripapillary PDs of the central rings and full ring and the central macular thickness of the XFG patients (P < 0.01 and P < 0.04, respectively, Pearson correlation). Conclusion: The peripapillary vascular parameters of the POAG and XFG patients were lower compared to those of normal participants. A correlation between clinical characteristics of POAG and XFG patients and PD was found. This may hint to a vascular mechanism in glaucoma either primary or secondary to intra-ocular pressure/OAG damage.

Exfoliation syndrome: association with systemic diseases-the Maccabi glaucoma study.

PURPOSE: To investigate the relationship between exfoliation syndrome (XFS) and systemic diseases. METHODS: A population-based, retrospective study with control group was conducted using the electronic medical database of Maccabi Health Services, the second largest Health Maintenance Organization (HMO) in Israel. Study population included Maccabi members from January 2003 to April 2016. Cases consisted of patients diagnosed with XFS regardless of glaucoma. The control group included Maccabi members without XFS, matched on age, sex, and ancestry, that were examined by an ophthalmologist within the last year. MAIN OUTCOME MEASURES: Associations between XFS and systemic diseases. RESULTS: We identified 16,388 patients with XFS, in whom 40.3% (n = 6613) had glaucoma. The control group included 14,015 patients. Mean age was 78.3 ± 8.9 years and 76.2 ± 8.5 years for the XFS and control group, respectively. In unconditional logistic regression analyses, after adjusting for age, sex, and ancestry, XFS was significantly associated with risk of cardiovascular diseases including hypertension (OR 1.07, 95% CI 1.01-1.13, p = 0.02), myocardial infarction (OR 1.21, 95% CI 1.17-1.31, p < 0.0001), and congestive heart failure (OR 1.70, 95% CI 1.55-1.88, p < 0.0001) as well as higher risk for high creatinine (OR 1.28, 95% CI 1.2-1.37, p < 0.0001). Diabetes mellitus and body mass index were inversely associated with XFS (OR 0.70, 95% CI 0.67-0.73, p < 0.0001 and OR 0.88, 95% CI 0.84-0.93, p < 0.0001, respectively). Overall cancer diagnoses were more common in the XFS group (OR 1.05, 95% CI 1.0-1.1, p = 0.05). XFS was associated with more hospitalizations (mean 5 ± 5.3 hospitalizations in the XFS group and 3.3 ± 4.0 in the controls, p < 0.0001). CONCLUSION: XFS is significantly associated with cardiovascular systemic diseases (in a population living in Israel and predominantly born in Russia).

Microarchitecture of Schlemm Canal Before and After Cataract Extraction Surgery.

PRECIS: Schlemm canal (SC) expands after cataract extraction (CE), both in the area and in volume by 25% as was measured using enhanced-depth imaging optical coherent tomography (EDI-OCT) in patients before and 1 week after CE. PURPOSE: This study aims to characterize the structural and volume changes on the microstructure of SC in patients before and after uneventful phacoemulsification CE by using EDI-OCT. MATERIALS AND METHODS: Forty-one serial horizontal EDI-OCT B-scans (interval between B-scans, 69 µm) were obtained in the nasal corneoscleral limbus before and 1 week after CE. The structure of aqueous channels, conjunctival blood vessels and iris anatomy in each scan were used as landmarks to select for overlapping scans taken before and following CE. The SC cross-section area was measured in each of the selected scans and SC volume was determined following a 3-dimensional reconstruction. RESULTS: Eleven eyes (6 females and 5 males) were imaged successfully before and after CE. Mean age was 70.54±11.38 years. The mean axial length was 23.10±0.87 mm. After CE, the mean best-corrected visual acuity in logMAR improved from 0.4±0.13 to 0.2±0.13 (P=0.028). There was no significant change in the mean intraocular pressure before and after CE (15.09±1.33 to 15.0±2.16 mm Hg; P=0.39). The mean SC cross-section area increased by 25%, from 4744±376 to 5941±1048 µm (P<0.001). SC volume in the analyzed region increased by 25% from 6,641,473±585,954 to 8,317,909±1,328,809 µm (P<0.001). CONCLUSION: CE expands SC dimensions in healthy eyes. EDI-OCT imaging of SC may prove useful in the evaluation of the SC dimensions in vivo before and after CE.

Overuse and Underuse of Visual Field Testing Over 15 Years.

PRéCIS:: A 15-year analysis of 198,843 visual field (VF) tests revealed a growing trend for their performance for nonglaucoma indications. Adherence to glaucoma management guidelines was suboptimal. Guidelines for referral to VF assessments should be established. PURPOSE: The purpose of this study was to identify trends in VF assessments over 15 years among patients with and without suspected or confirmed glaucoma, in a large healthcare maintenance organization. METHODS: This was a population-based retrospective cohort study, conducted by means of electronic medical database analyses. STUDY POPULATION: Maccabi Healthcare Services is an healthcare maintenance organization that insures 2 million members constituting 25% of the population. All members who underwent at least 1 VF test between January 2000 and December 2014 were included. In addition, all members with glaucoma or suspected glaucoma diagnosis or who were prescribed with antiglaucoma medications were evaluated. MAIN OUTCOME MEASURES: VF performance rates. RESULTS: A total of 93,617 Maccabi Healthcare Services members underwent 198,843 VF tests; of whom 47.9% involved patients without any glaucoma-related conditions. There was a growing trend over time toward more of those members to undergo VF tests and, by 2014, non-glaucoma-related members comprised 74.0% of new VF assessments. In contrast, 32.3% of glaucoma-related patients did not perform even 1 VF test throughout the entire study period. Although over 2 years (25.95±6.33 mo) passed between the first glaucoma-related diagnosis and first VF test, once a patient underwent the first VF test, an average once-a-year VF follow-up (0.95±0.37 annual tests) began. CONCLUSION: There is a growing trend for VF tests being apparently overused for indications other than glaucoma. Concurrently, adherence to glaucoma management guidelines on VF tests is suboptimal, leading to discernible underuse. Guidelines for VF assessments in nonglaucoma patients should be established. Adherence to existing glaucoma management guidelines should be improved.

LOXL1 Polymorphisms: Genetic Biomarkers that Presage Environmental Determinants of Exfoliation Syndrome.

An agnostic high throughput search of the genome revealed a robust association between LOXL1 genetic polymorphisms and exfoliation syndrome (XFS), a discovery that likely would not have been possible with candidate or family-based gene search strategies. While questions remain regarding how LOXL1 gene variants contribute to XFS pathogenesis, it is clear that the frequencies of disease-related alleles do not track with the varying disease burden throughout the world, prompting a search for environmental risk factors. A geo-medicine approach revealed that disease load seemed to increase as a function of the distance from the equator. The exact reason for this extraequatorial disease distribution pattern remains unclear, but a greater amount of time spent outdoors is a robust risk factor for XFS, suggesting climatic factors such as ocular solar exposure and colder ambient temperature may be involved in disease pathogenesis. Prospective studies have also implicated higher coffee consumption and lower dietary folate intake in association with incident XFS. The discovery of environmental risk factors for XFS suggests that preventive measures may help to reduce ocular morbidity from XFS.

A Role for Clusterin in Exfoliation Syndrome and Exfoliation Glaucoma?

The multifunctional protein clusterin (CLU) is a secreted glycoprotein ubiquitously expressed throughout the body, including in the eye. Its primary function is to act as an extracellular molecular chaperone, preventing the precipitation and aggregation of misfolded extracellular proteins. Clusterin is commonly identified at fluid-tissue interfaces, and has been identified in most body fluids. It is a component of exfoliation material, and CLU mRNA is reduced in eyes with exfoliation syndrome compared with controls. SNPs located in the CLU genomic region have been associated with Alzheimer disease (AD) at the genome-wide level and several CLU SNPs located in an apparent regulatory region have been nominally associated with XFS/XFG in Caucasians with European ancestry and in south Indians. Interestingly, clusterin associates with altered elastic fibers in human photoaged skin and prevents UV-induced elastin aggregation in vitro. In light of the known geographic risk factors for XFS/XFG, which could include UV light, investigations of CLU-geographic interactions could be of interest. Future studies investigating rare CLU variation and other complex interactions including gene-gene interactions in XFS/XFG cases and controls may also be fruitful. Although CLU has been considered as a therapeutic target in AD, cancer and dry eye, a role for clusterin in XFS/XFG needs to be better defined before therapeutic approaches involving CLU can be entertained.

Ranibizumab for persistent diabetic macular edema after bevacizumab treatment.

PURPOSE: To evaluate the efficacy of switching from bevacizumab to ranibizumab in patients with diabetic macular edema (DME). METHODS: This was a retrospective study of patients with DME initially treated with bevacizumab and switched to ranibizumab. Visual acuity (VA) and central retinal thickness (CRT) were retrieved at fixed timepoints prior to and after the switch. RESULTS: Forty eyes of 32 patients were included in the study. The difference in VA between any of these fixed timepoints was not statistically significant. A significant gain in VA was found in eyes that lost more than 0.1 logMAR during treatment with the last 3 bevacizumab injections. The mean CRT was significantly lower after the first 3 ranibizumab injections and at the final follow-up (p<0.001), a 67 ± 14 µm and 78 ± 18 µm reduction in thickness, respectively. CONCLUSIONS: Switching to ranibizumab resulted in a significant decrease in the CRT of eyes with DME, and should be considered when there is a lack of response or deterioration while on bevacizumab injections. A significant gain in VA was observed in a subgroup of eyes that lost more than one line while receiving the last 3 bevacizumab injections prior to the switch.

The Maccabi Glaucoma Study: Treatment Patterns and Persistence With Glaucoma Therapy in a Large Israeli Health Maintenance Organization.

PURPOSE: To describe treatment patterns, adherence, and persistence with initial therapy among glaucoma patients in the community. MATERIALS AND METHODS: A population-based historical prospective cohort study, using the electronic medical databases of Maccabi Healthcare Services, a 2 million member health maintenance organization in Israel. Newly diagnosed glaucoma patients between 2003 and 2010, who purchased at least 1 antiglaucoma medication, were followed up to December 31, 2012. Outcome measures included medication adherence analyzed by proportion of days covered by drugs during follow-up time, and persistence with initial therapy measured by time until switch or discontinuation of first-line therapy. RESULTS: A total of 5934 incident definite glaucoma patients were identified, 13% of whom were nonadherent with therapy (covered <20% of the follow-up time), and only 25% exhibited high adherence (covered at least 80% of the follow-up period). Adherence was positively associated with female sex, age, socioeconomic status, frequent follow-up visits, and higher baseline intraocular pressure. Lower median adherence (P<0.01) was observed among patients of normal tension glaucoma (52%) and angle closure (59%) as compared with open angle (65%) and exfoliation glaucoma (68%). Patients treated by glaucoma specialists had similar adherence to those treated by general ophthalmologists (proportion of days covered=65% vs. 63%, P=0.42). Persistence with initial line of therapy varied by type of medication, with prostaglandin initiators exhibiting the highest persistence (13% reduced likelihood of switch or discontinuation as compared with ß-blockers, P<0.01) and α-agonists the lowest persistence (39% increased likelihood of switch or discontinuation as compared with ß-blockers, P<0.01). CONCLUSIONS: This large-scale analysis of real-world use of glaucoma medications reveals that adherence to glaucoma therapy is associated with medication type, patient's sex, age, socioeconomic status, type of glaucoma, follow-up visits, and baseline intraocular pressure.

Retinal ganglion cell apoptotic pathway in glaucoma: Initiating and downstream mechanisms.

Apoptosis of retinal ganglion cells (RGCs) in glaucoma causes progressive visual field loss, making it the primary cause of irreversible blindness worldwide. Elevated intraocular pressure and aging, the main risk factors for glaucoma, accelerate RGC apoptosis. Numerous pathways and mechanisms were found to be involved in RGC death in glaucoma. Neurotrophic factors deprivation is an early event. Oxidative stress, mitochondrial dysfunction, inflammation, glial cell dysfunction, and activation of apoptotic pathways and prosurvival pathways play a significant role in RGC death in glaucoma. The most important among the involved pathways are the MAP-kinase pathway, PI-3 kinase/Akt pathway, Bcl-2 family, caspase family, and IAP family.

Epiretinal transplantation of human bone marrow mesenchymal stem cells rescues retinal and vision function in a rat model of retinal degeneration.

Vision incapacitation and blindness associated with incurable retinal degeneration affect millions of people worldwide. In this study, 0.25×10(6) human bone marrow stem cells (hBM-MSCs) were transplanted epiretinally in the right eye of Royal College Surgeons (RCS) rats at the age of 28 days. Epiretinally transplanted cells were identified as a thin layer of cells along vitreous cavity, in close proximity to the retina or attached to the lens capsule, up to 6 weeks following transplantation. Epiretinal transplantation delayed photoreceptor degeneration and rescued retinal function up to 20 weeks following cell transplantation. Visual functions remained close to normal levels in epiretinal transplantation rats. No inflammation or any other adverse effects were observed in transplanted eyes. Our findings suggest that transplantation of hBM-MSCs as a thin epiretinal layer is effective for treatment of retinal degeneration in RCS rats, and that transplanting the cells in close proximity to the retina enhances hBM-MSC therapeutic effect compared with intravitreal injection.

Association of clusterin (CLU) variants and exfoliation syndrome: An analysis in two Caucasian studies and a meta-analysis.

Exfoliation syndrome (XFS) is an important risk factor for glaucoma (XFG) worldwide. LOXL1 variants are highly associated with XFS in most populations; however, the high frequency of risk alleles in normal individuals and the reversal of risk alleles in different ethnic populations suggest that other factors contribute to XFS pathogenesis. Clusterin (CLU) is an extracellular matrix chaperone that prevents protein aggregation and is highly expressed in ocular tissues affected by XFS. Studies examining common CLU variants for association with XFS have been inconsistent. The purpose of this study was to evaluate CLU variants for association with XFS in two independent datasets from the United States (222 cases and 344 controls) and Israel (92 cases and 102 controls). Seven tag SNPs that captured >95% of alleles at r(2) greater than 0.8 across the CLU genomic region were genotyped using TaqMan assays. Genotypes for an additional SNP, rs2279590, were imputed using phased haplotypes of HapMap reference CEU samples. Of the 8 CLU SNPs selected for the study, none were significantly associated with XFS in either case-control group (age and sex adjusted P > 0.14 and 0.36, respectively, in the US and Israeli datasets), or when they were meta-analyzed together (age and sex adjusted P > 0.13). Haplotype analysis using all 8 SNPs or only the promoter region SNPs also did not show significant associations of CLU with XFS in the combined US and Israeli dataset (P > 0.28). Meta-analysis of the data from this study and previous studies in Caucasian populations (1184 cases and 978 controls) resulted in statistically significant association of rs2279590 with XFS (summary OR = 1.18, 95% CI: 1.03-1.33, P = 0.01). Significant association between rs2279590 and XFS was also found in Indian populations (summary OR = 0.76, 95% CI: 0.61-0.96; P = 0.02); however, significant heterogeneity between the Caucasian and Indian populations possibly due to reversal of the risk allele precluded an overall meta-analysis for rs2279590 (Q = 0.001, I(2) = 91%). No significant association was identified for rs3087554 in either Caucasian populations (summary OR = 0.90, 95% CI: 0.77-1.05, P = 0.17) or Indian populations (summary OR = 0.89, 95% CI: 0.72-1.10, P = 0.28), or in both populations combined (1705 cases and 3713 controls; summary OR = 0.90, 95% CI: 0.79-1.01, P = 0.08). Significant heterogeneity precluded the addition of the Japanese data to the meta-analysis for rs3087554 (Q = 0.006, I(2) = 87%). Our results suggest that common CLU variants may contribute to modest XFS risk but even larger datasets are required to confirm these findings.

Solar exposure and residential geographic history in relation to exfoliation syndrome in the United States and Israel.

IMPORTANCE: Residential (geographic) history and extent of solar exposure may be important risk factors for exfoliation syndrome (XFS) but, to our knowledge, detailed lifetime solar exposure has not been previously evaluated in XFS. OBJECTIVE: To assess the relation between residential history, solar exposure, and XFS. DESIGN, SETTING, AND PARTICIPANTS: This clinic-based case-control study was conducted in the United States and Israel. It involved XFS cases and control individuals (all ≥ 60-year-old white individuals) enrolled from 2010 to 2012 (United States: 118 cases and 106 control participants; Israel: 67 cases and 72 control participants). MAIN OUTCOMES AND MEASURES: Weighted lifetime average latitude of residence and average number of hours per week spent outdoors as determined by validated questionnaires. RESULTS: In multivariable analyses, each degree of weighted lifetime average residential latitude away from the equator was associated with 11% increased odds of XFS (pooled odds ratio [OR], 1.11; 95% CI, 1.05-1.17; P < .001). Furthermore, every hour per week spent outdoors during the summer, averaged over a lifetime, was associated with 4% increased odds of XFS (pooled OR, 1.04; 95% CI, 1.00-1.07; P = .03). For every 1% of average lifetime summer time between 10 am and 4 pm that sunglasses were worn, the odds of XFS decreased by 2% (OR, 0.98; 95% CI, 0.97-0.99; P < .001) in the United States but not in Israel (OR, 1.00; 95% CI, 0.99-1.01; P = .92; P for heterogeneity = .005). In the United States, after controlling for important environmental covariates, history of work over water or snow was associated with increased odds of XFS (OR, 3.86; 95% CI, 1.36-10.9); in Israel, there were too few people with such history for analysis. We did not identify an association between brimmed hat wear and XFS (P > .57). CONCLUSIONS AND RELEVANCE: Lifetime outdoor activities may contribute to XFS. The association with work over snow or water and the lack of association with brimmed hat wear suggests that ocular exposure to light from reflective surfaces may be an important type of exposure in XFS etiology.

The Maccabi Glaucoma Study: prevalence and incidence of glaucoma in a large israeli health maintenance organization.

PURPOSE: To investigate the prevalence and incidence of glaucoma in a large health maintenance organization (HMO) in Israel. DESIGN: A population-based retrospective cohort study, conducted using electronic medical database. METHODS: Collected data included personal and medical characteristics. SETTING: Maccabi Healthcare Services, the second-largest HMO in Israel, insuring 2 million members and serving 25% of the population with a nationwide distribution. STUDY POPULATION: Maccabi members from January 2003 to December 2010. MAIN OUTCOME MEASURES: Prevalence and incidence of glaucoma according to the International Classification of Diseases, 9th revision, Clinical Modification diagnostic codes. RESULTS: A total of 15,708 prevalent glaucoma patients were identified among active members of Maccabi in December 2010. A total of 15,332 (97.6%) were 40 years or older, with a point prevalence of 2.2%. Prevalence of glaucoma was strongly associated with age, ranging from 0.28% at age 40-50 to 9.2% among elderly aged 80 or above. The 5 most prevalent diagnoses were open-angle glaucoma (1.61%), exfoliation glaucoma (0.20%), unspecified glaucoma (0.17%), angle closure (0.11%), and normal tension glaucoma (0.06%). We identified 6674 incident glaucoma patients diagnosed between 2003 and 2010. The observed incidence density rate among 40+-year-old members was 1.84 (1.79-1.88) new cases per 1000 person-years. Median age at diagnosis was 64 years old. The risk of glaucoma was similar between sexes up to age 70 years, and was significantly (P<.01) higher in men in older ages. CONCLUSIONS: Glaucoma affects nearly 10% of the elderly population in Maccabi, with the highest risk of diagnosis at age 70-74. Since glaucoma leads to irreversible vision loss, the present estimates of morbidity should be of significant concern.

Minocycline upregulates pro-survival genes and downregulates pro-apoptotic genes in experimental glaucoma.

PURPOSE: Minocycline, a second-generation tetracycline with anti-inflammatory and anti-apoptotic properties, was reported to be neuroprotective in experimental glaucoma and optic nerve transection as well as in other neurodegenerative diseases. The purpose of this study was to investigate the mechanism underlying that neuroprotective effect in murine glaucoma. METHODS: Elevated intraocular pressure was induced in 159 rats by the translimbal photocoagulation laser model. Minocycline 22 mg/kg or saline was injected intraperitoneally starting 3 days before the induction of glaucoma, and continued daily until the animals were sacrificed. The effect of minocycline on gene expression was evaluated using a quantitative polymerase chain reaction (PCR) array for apoptosis. The involvement of selected pro-apoptotic, pro-survival, and inflammatory genes was further analyzed by quantitative real-time PCR at multiple time points. Immunohistochemistry was used to study the effect of minocycline on microglial activation and to localize Bcl-2 changes. RESULTS: Minocycline significantly increased the anti-apoptotic gene Bcl-2 expression at day 8 and day 14 after the induction of glaucoma (p = 0.04 and p = 0.03 respectively), and decreased IL-18 expression in the retina at day 14 and day 30 (p = 0.04 and p < 0.001 respectively). PCR arrays suggested that additional genes were affected by minocycline, including Tp53bp2, TRAF4, osteoprotegerin, caspase 1 and 4, and members of the tumor necrosis factor superfamily. Additionally, minocycline decreased the amount of activated microglia in glaucomatous eyes. CONCLUSIONS: These results suggest that minocycline upregulates pro-survival genes and downregulates apoptotic genes, thus shifting the balance toward the anti-apoptotic side in experimental glaucoma.

Minocycline mechanism of neuroprotection involves the Bcl-2 gene family in optic nerve transection.

The second-generation tetracycline, minocycline, has been shown to exhibit neuroprotective therapeutic benefits in many neurodegenerative diseases including experimental glaucoma and optic nerve transection (ONT). This study investigated the mechanism underlying minocycline neuroprotection in a model of ONT. ONT was applied unilaterally in 36 Wistar rat eyes. The rats were randomly divided into a minocycline (22 mg/kg/d) treatment group and a saline treatment group (control). Treatment (minocycline or saline) was given by intraperitoneal injections initiated 3 d before ONT and continued daily until the end of the experiment. The involvement of pro-apoptotic, pro-survival and inflammatory pathways was analyzed by quantitative Real-Time Polymerase Chain Reaction at 4 h and 3 d after the transection in both treatment groups. The involvement of Bcl-2 protein was evaluated by immunohistochemistry. We found that Minocycline significantly increased the expression of the antiapoptotic gene bcl-2 4 h after transection (n = 8, p = 0.008) and decreased the expression of Bax at the same time point (n = 8, p = 0.03). Tumor Necrosis Factor α (TNFα), Inhibitor of Apoptosis Protein (IAP1) and Gadd45α were significantly upregulated in the retinas of eyes with ONTs compared to control (n = 10 for each gene, p = 0.02, p = 0.03, p = 0.04, respectively) but this effect was unaffected by minocycline. This study further support that the mechanism underlying minocycline neuroprotection involves the Bcl-2 gene family, suggesting that minocycline has antiapoptotic properties that support its value as a promising neuroprotective drug.

Transplantation of human bone marrow mesenchymal stem cells as a thin subretinal layer ameliorates retinal degeneration in a rat model of retinal dystrophy.

Vision incapacitation and blindness associated with retinal degeneration affect millions of people worldwide. Cell based therapy and specifically transplantation of human adult bone marrow-derived stem cells (hBM-MSCs) present possible treatment strategy. Subretinal transplantation of human or rat BM-MSCs was shown previously to improve retinal function in Royal College Surgeons (RCS) rats. In those studies cells were transplanted via a transscleral-transchoroidal approach, creating a localized subretinal bleb. Limited number of cells could be injected and photoreceptor rescue was restricted to areas in proximity to the injection site. Here we describe a new surgical method for subretinal transplantation that facilitates uniform distribution of transplanted cells as a thin layer along most of the subretinal space. We assessed the therapeutic effect of hBM-MSCs on RCS rats when transplanted either subretinally or intravitreally. We also examined whether a second transplantation can prolong the therapeutic effect. A cell suspension of 2.5 × 10(6) cells in 5 µl was injected subretinally or intravitreally in RCS rats at 28 days postnatal. In the subretinal group, hBM-MSCs were transplanted posterior to the limbus in the superotemporal part of the eye through a longitudinal triangular scleral tunnel reaching the choroid. In the intravitreal group, the cells were injected into the superotemporal part of the vitreous cavity. In cross sections of subretinally transplanted eyes, removed 2 h following transplantation, hBM-MSCs were distributed as a near-homogenous thin layer along most of the subretinal space. In some animals the cells were also detected in the choroid. In the intravitreal injection group, hBM-MSCs were clustered in the vitreous cavity. Transplanted cells could be detected up to 2 weeks after transplantation but not at later time points. Retinal function and structure were assessed by electroretinogram (ERG) and histology analysis, respectively. Six weeks post transplantation, the mean maximal scotopic ERG b-wave amplitude response recorded in RCS control eyes was 1.2 µV. By contrast, in transplanted eyes mean responses of 56.4 µV and 66.2 µV were recorded in the intravitreally and subretinally transplanted eyes, respectively. In the subretinal group, retinal function was significantly higher in transplanted compared with control eyes up to 20 weeks following transplantation. By contrast, in the intravitreal group, rescue of retinal function persisted only up to 12 weeks following transplantation. Histological analysis revealed that 8 weeks following subretinal transplantation, the retinas of control eyes were dystrophic, with outer nuclear layer (ONL) containing a single cell layer. An extensive photoreceptor rescue was demonstrated in transplanted eyes at this time point, with 3-4 cell layers in the ONL along the entire retina. A second subretinal transplantation at 70 days postnatal did not enhance or prolong the therapeutic effect of hBM-MSCs. No immunosuppressants were used and long-term safety analysis demonstrated no gross or microscopic adverse effects. Taken together our findings suggest that transplantation of hBM-MSCs as a thin subretinal layer enhances the therapeutic effect and the safety of cell transplantation.

Comparison between axonal and retinal ganglion cell gene expression in various optic nerve injuries including glaucoma.

PURPOSE: The pathogenesis of retinal ganglion cell loss in glaucoma remains incompletely understood. Current evidence suggests that the optic nerve (ON) head and axons are the main site of injury in glaucoma. This study compares changes in prosurvival and proapoptotic gene expression in ONs with those in retinas in three models of ocular injury, specifically ON transection (ONTX), N-methyl-D-aspartate (NMDA) retinal toxicity, and experimental glaucoma. METHODS: Rats (n=240) were divided into three models (ONTX, NMDA retinal toxicity, and experimental glaucoma). The experimental model was induced unilaterally and the contralateral eye served as control. Rats were sacrificed at 4-5 different time points specific for each model. ONs and retinas were isolated for real-time PCR investigation of expression of selected genes. Immunohistochemistry localized changes in inhibitor of apoptosis (IAP)-1 and X-linked IAP (XIAP) proteins in retinas and ONs. Colocalization was measured using Imaris colocalization software (three-dimensional analysis). RESULTS: The earliest changes in gene expression occurred in ONs in the ONTX model and in retinas in the NMDA model, as expected. However, some gene changes occurred first in ONs, while others occurred first in retinas in the glaucoma model. The expression patterns of the prosurvival genes IAP-1 and XIAP differed between retinas and ONs of glaucomatous eyes: Both were upregulated in the retinas, but XIAP was downregulated in the ONs, while IAP-1 stayed unchanged. Colocalization of IAP-1, XIAP, glial fibrillary acidic protein, and Thymus cell antigen-1 (Thy-1) suggested that IAP-1 was colocalized mostly with Thy-1 and XIAP with glial fibrillary acidic protein in the ONs. Members of the B-cell lymphoma 2 (BCL-2) family were similarly involved in the ONs and retinas of glaucomatous, transected, and NMDA-injected eyes. The expression of the prosurvival genes, Bcl-2 and Bcl-xl, decreased significantly in both the ONs and retinas of injured eyes. The proapoptotic genes, BCL2-associated X protein (BAX) and Bcl-2-associated death promoter (BAD), were significantly upregulated in both injured retinas and ONs. CONCLUSIONS: The overexpression of XIAP and IAP-1 genes in the retinas was not associated with similar changes in the ONs of glaucomatous eyes. The lack of activation of these prosurvival genes in the ONs may explain the increased vulnerability of ONs to elevated intraocular pressure.

Increase in retinal ganglion cells' susceptibility to elevated intraocular pressure and impairment of their endogenous neuroprotective mechanism by age.

PURPOSE: To investigate age-associated changes in retinal ganglion cell (RGC) response to elevated intraocular pressure (IOP), and to explore the mechanism underlying these changes. Specifically, the effect of aging on inhibitor of apoptosis (IAP) gene family expression was investigated in glaucomatous eyes. METHODS: IOP was induced unilaterally in 82 Wistar rats using the translimbal photocoagulation laser model. IOP was measured using a TonoLab tonometer. RGC survival was evaluated in 3-, 6-, 13-, and 18-month-old animals. Changes in the RNA profiles of young (3-month-old) and old glaucomatous retinas were examined by PCR array for apoptosis; changes in selected genes were validated by real-time PCR; and changes in selected proteins were localized by immunohistochemistry. RESULTS: There were no significant IOP differences between the age groups. However, there was a natural significant loss of RGCs with aging and this was more prevalent in glaucomatous eyes. The number of RGCs in glaucomatous eyes decreased from 669±123 RGC/mm² at 3 months to 486±114 RGC/mm² at 6 months and 189±46.5 RGC/mm² at 18 months (n=4-8, p=0.048, analysis of variance). The PCR array revealed different changes in proapoptotic and prosurvival genes between young and old eyes. The two important prosurvival genes, IAP-1 and X-linked IAP (XIAP), acted in opposite directions in 3-month-old and 15-month-old rats, and were significantly decreased in aged glaucomatous retinas, while their expression increased significantly in young glaucomatous eyes. P53 levels did not vary between young glaucomatous and normal fellow eyes, but were reduced with age. B-cell leukemia/lymphoma 2 (Bcl-2) family members and tumor necrosis factor (TNF)-α expression were unaffected by age. Immunohistochemistry results suggested that the sources of changes in IAP-1 protein expression are RGCs and glial cells, and that most XIAP secretion comes from RGCs. CONCLUSIONS: Decreased IAP-1 and XIAP gene expression in aged eyes may predispose RGCs to increased vulnerability to glaucomatous damage. These findings suggest that aging impairs the endogenous neuroprotective mechanism of RGCs evoked by elevated IOP.

The surgical management of massive intraoperative and postoperative suprachoroidal hemorrhage: anatomic and functional outcomes.

PURPOSE: To describe the clinical characteristics, management and treatment outcomes of patients with post-surgical suprachoroidal hemorrhage (SCH). METHODS: A retrospective cross-sectional study was conducted, in which the medical records of 9 consecutive patients with SCH admitted to the Goldschleger Eye Institute were reviewed. RESULTS: The mean age was 74 years (range 61-84) and the mean follow-up time was 38.3 ± 0.1 months (range 4-87 months). Four cases were associated with glaucoma surgeries (2 trabeculectomies and 2 Ahmed valve implantations), 3 cases with cataract surgery and 2 cases with pars plana vitrectomy. The diagnosis of SCH was ranging from intra-operative to 8 days following the primary procedure. Most patients underwent posterior sclerotomies and drainage alone or combined with pars plana vitrectomy in a mean timing of intervention of 11 ± 4 days. At one month of follow-up the visual acuity improved in 7 eyes and remained stable in 2, compared to the VA prior to the drainage operation. The mean VA improved from 2.03 to 1.285 logMAR units at 1 month following the drainage procedure (p=0.003). CONCLUSIONS: SCH still remains a challenging complication of many ophthalmological procedures. The current surgical management may improve visual acuity though the general prognosis is still poor.