Glaucoma

Yin Y, Benowitz LI. In Vitro and In Vivo Methods for Studying Retinal Ganglion Cell Survival and Optic Nerve Regeneration. Methods Mol Biol 2018;1695:187-205.Abstract
Glaucoma is marked by a progressive degeneration of the optic nerve and delayed loss of retinal ganglion cells (RGCs), the projection neurons of the eye. Because RGCs are not replaced and because surviving RGCs cannot regenerate their axons, the visual loss in glaucoma is largely irreversible. Here, we describe methods to evaluate treatments that may be beneficial for treating glaucoma using in vitro cell culture models (immunopanning to isolate neonatal RGCs, dissociated mature retinal neurons, retinal explants) and in vivo models that test potential treatments or investigate underlying molecular mechanisms in an intact system. Potentially, use of these models can help investigators continue to improve treatments to preserve RGCs and restore visual function in patients with glaucoma.
Chou JC, Cousins CC, Miller JB, Song BJ, Shen LQ, Kass MA, Wiggs JL, Pasquale LR. Fundus Densitometry Findings Suggest Optic Disc Hemorrhages in Primary Open-Angle Glaucoma Have an Arterial Origin. Am J Ophthalmol 2018;187:108-116.Abstract
PURPOSE: To analyze optic disc hemorrhages (DH) associated with primary open-angle glaucoma by quantifying their geometric profile and comparing their densitometry with hemorrhages from retinal vein occlusions (RVO) and retinal macroaneurysms (MA), which have venous and arterial sources of bleeding, respectively. DESIGN: Retrospective cross-sectional study. METHODS: Setting: Massachusetts Eye & Ear. POPULATION: Fundus images of DH (n = 40), MA (n = 14), and RVO (n = 25) were identified. Patient clinical backgrounds and demographics were obtained. MAIN OUTCOME MEASURES: Grayscale pixel intensity units of hemorrhages and adjacent arteriole and venule over the same background tissue were measured. Densitometry differentials (arteriole or venule minus hemorrhage [ΔA and ΔV, respectively]) were calculated. The ratios of length (radial) to midpoint width for DH were calculated. Mean ΔA and ΔV between groups were compared with t tests. Multiple linear regression assessed the relation of retinal hemorrhage diagnosis to ΔA and ΔV and of DH shape to ΔA and ΔV. RESULTS: Mean (± standard deviation) ΔA and ΔV for DH (6.9 ± 7.1 and -4.7 ± 8.0 pixel intensity units, respectively) and MA (5.3 ± 5.9 and -6.0 ± 4.6, respectively) were comparable (P ≥ .43). Mean ΔA (14.6 ± 7.7) and ΔV (6.4 ± 6.3) for RVO were significantly higher compared to DH and MA (P < .0001) and remained significant in multivariable analyses. A unit increase in DH length-to-width ratio was associated with 1.2 (0.5) and 1.3 (0.5) pixel intensity unit (standard error) decrease in ΔA and ΔV, respectively (P ≤ .014). CONCLUSIONS: DH have densitometry profiles comparable to MA and different from RVO, suggesting that DH in glaucoma have an arterial origin.
Lin S-C, Pasquale LR, Singh K, Lin SC. The Association Between Body Mass Index and Open-angle Glaucoma in a South Korean Population-based Sample. J Glaucoma 2018;27(3):239-245.Abstract
PURPOSE: The purpose of this article is to investigate the association between body mass index (BMI) and open-angle glaucoma (OAG) in a sample of the South Korean population. MATERIALS AND METHODS: The sample consisted of a cross-sectional, population-based sample of 10,978 participants, 40 years of age and older, enrolled in the 2008 to 2011 Korean National Health and Nutrition Examination Survey. All participants had measured intraocular pressure <22 mm Hg and open anterior chamber angles. OAG was defined using disc and visual field criteria established by the International Society for Geographical and Epidemiological Ophthalmology. Multivariable analyses were performed to determine the association between BMI and OAG. These analyses were also performed in a sex-stratified and age-stratified manner. RESULTS: After adjusting for potential confounding variables, lower BMI (<19 kg/m) was associated with greater risk of OAG compared with normal BMI (19 to 24.9 kg/m) [odds ratio (OR), 2.28; 95% confidence interval (CI), 1.22-4.26]. In sex-stratified analyses, low BMI remained adversely related to glaucoma in women (OR, 3.45; 95% CI, 1.42-8.38) but not in men (OR, 1.72; 95% CI, 0.71-4.20). In age-stratified analyses, lower BMI was adversely related to glaucoma among subjects 40- to 49-year old (OR, 5.16; 95% CI, 1.86-14.36) but differences in glaucoma prevalence were not statistically significant between those with low versus normal BMI in other age strata. CONCLUSIONS: Lower BMI was associated with increased odds of OAG in a sample of the South Korean population. Multivariate analysis revealed the association to be statistically significant in women and those in the youngest age stratum.
Bains U, Hoguet A. Aqueous Drainage Device Erosion: A Review of Rates, Risks, Prevention, and Repair. Semin Ophthalmol 2017;:1-10.Abstract
Aqueous drainage device tube erosions require prompt intervention to prevent endophthalmitis. As the use of drainage devices in glaucoma surgery continues to increase, recognizing and managing tube erosions is a pertinent issue. This review provides a comprehensive overview of tube erosions, including the rates of erosion with various types of patch grafts, the risk factors associated with erosion, and approaches to repair in order to counsel and treat our patients to prevent endophthalmitis.
Haleem MS, Han L, van Hemert J, Li B, Fleming A, Pasquale LR, Song BJ. A Novel Adaptive Deformable Model for Automated Optic Disc and Cup Segmentation to Aid Glaucoma Diagnosis. J Med Syst 2017;42(1):20.Abstract
This paper proposes a novel Adaptive Region-based Edge Smoothing Model (ARESM) for automatic boundary detection of optic disc and cup to aid automatic glaucoma diagnosis. The novelty of our approach consists of two aspects: 1) automatic detection of initial optimum object boundary based on a Region Classification Model (RCM) in a pixel-level multidimensional feature space; 2) an Adaptive Edge Smoothing Update model (AESU) of contour points (e.g. misclassified or irregular points) based on iterative force field calculations with contours obtained from the RCM by minimising energy function (an approach that does not require predefined geometric templates to guide auto-segmentation). Such an approach provides robustness in capturing a range of variations and shapes. We have conducted a comprehensive comparison between our approach and the state-of-the-art existing deformable models and validated it with publicly available datasets. The experimental evaluation shows that the proposed approach significantly outperforms existing methods. The generality of the proposed approach will enable segmentation and detection of other object boundaries and provide added value in the field of medical image processing and analysis.
Rahman SI, Turalba A. Anticoagulation in Glaucoma Surgery. Semin Ophthalmol 2017;:1-4.Abstract
Anticoagulation medications are used commonly, particularly in an elderly population. There are many systemic diseases and scenarios that require modulation of coagulation to prevent serious adverse outcomes. While there is some consensus about their use in cataract surgery, there is less certainty about their management with glaucoma surgery. Glaucoma surgery presents a unique challenge when considering anticoagulation. Currently, there is great diversity in surgeon practices regarding anticoagulation in glaucoma surgery. Based on available evidence, it is unclear whether it is beneficial to hold anticoagulation, with or without bridging therapy, leading up to a planned surgery. Considering the potential serious adverse outcomes related to holding anticoagulation therapy, altering these medications for glaucoma surgery should be done sparingly and in consultation with the primary prescriber of such medications.
Chintalapudi SR, Maria D, Di Wang X, Bailey JCN, Bailey JCN, Bailey JCN, Hysi PG, Wiggs JL, Williams RW, Jablonski MM. Systems genetics identifies a role for Cacna2d1 regulation in elevated intraocular pressure and glaucoma susceptibility. Nat Commun 2017;8(1):1755.Abstract
Glaucoma is a multi-factorial blinding disease in which genetic factors play an important role. Elevated intraocular pressure is a highly heritable risk factor for primary open angle glaucoma and currently the only target for glaucoma therapy. Our study helps to better understand underlying genetic and molecular mechanisms that regulate intraocular pressure, and identifies a new candidate gene, Cacna2d1, that modulates intraocular pressure and a promising therapeutic, pregabalin, which binds to CACNA2D1 protein and lowers intraocular pressure significantly. Because our study utilizes a genetically diverse population of mice with known sequence variants, we are able to determine that the intraocular pressure-lowering effect of pregabalin is dependent on the Cacna2d1 haplotype. Using human genome-wide association study (GWAS) data, evidence for association of a CACNA2D1 single-nucleotide polymorphism and primary open angle glaucoma is found. Importantly, these results demonstrate that our systems genetics approach represents an efficient method to identify genetic variation that can guide the selection of therapeutic targets.
Learned D, Eliott D. Management of Delayed Suprachoroidal Hemorrhage after Glaucoma Surgery. Semin Ophthalmol 2017;:1-5.Abstract
PURPOSE: To review the most current treatment recommendations and outcomes for delayed suprachoroidal hemorrhages. METHODS: Article review of management and outcomes of suprachoroidal hemorrhages, with emphasis on delayed suprachoroidal hemorrhages in the setting of glaucoma surgery. CONCLUSION: Time of drainage of suprachoroidal hemorrhages remains controversial. Earlier drainage should be considered with high intraocular pressure, expulsion of intraocular content, or retinal detachment. In clinically stable eyes with suprachoroidal hemorrhage, recommendations range from observation to immediate drainage. Clot lysis occurs at roughly 14 days.
Thomson BR, Souma T, Tompson SW, Onay T, Kizhatil K, Siggs OM, Feng L, Whisenhunt KN, Yanovitch TL, Kalaydjieva L, Azmanov DN, Finzi S, Tanna CE, Hewitt AW, Mackey DA, Bradfield YS, Souzeau E, Javadiyan S, Wiggs JL, Pasutto F, Liu X, John SWM, Craig JE, Jin J, Young TL, Quaggin SE. Angiopoietin-1 is required for Schlemm's canal development in mice and humans. J Clin Invest 2017;Abstract
Primary congenital glaucoma (PCG) is a leading cause of blindness in children worldwide and is caused by developmental defects in 2 aqueous humor outflow structures, Schlemm's canal (SC) and the trabecular meshwork. We previously identified loss-of-function mutations in the angiopoietin (ANGPT) receptor TEK in families with PCG and showed that ANGPT/TEK signaling is essential for SC development. Here, we describe roles for the major ANGPT ligands in the development of the aqueous outflow pathway. We determined that ANGPT1 is essential for SC development, and that Angpt1-knockout mice form a severely hypomorphic canal with elevated intraocular pressure. By contrast, ANGPT2 was dispensable, although mice deficient in both Angpt1 and Angpt2 completely lacked SC, indicating that ANGPT2 compensates for the loss of ANGPT1. In addition, we identified 3 human subjects with rare ANGPT1 variants within an international cohort of 284 PCG patients. Loss of function in 2 of the 3 patient alleles was observed by functional analysis of ANGPT1 variants in a combined in silico, in vitro, and in vivo approach, supporting a causative role for ANGPT1 in disease. By linking ANGPT1 with PCG, these results highlight the importance of ANGPT/TEK signaling in glaucoma pathogenesis and identify a candidate target for therapeutic development.
Aschard H, Kang JH, Iglesias AI, Hysi P, Cooke Bailey JN, Khawaja AP, Allingham RR, Ashley-Koch A, Lee RK, Moroi SE, Brilliant MH, Wollstein G, Schuman JS, Fingert JH, Budenz DL, Realini T, Gaasterland T, Scott WK, Singh K, Sit AJ, Igo RP, Song YE, Hark L, Ritch R, Rhee DJ, Gulati V, Haven S, Vollrath D, Zack DJ, Medeiros F, Weinreb RN, Cheng C-Y, Chasman DI, Christen WG, Pericak-Vance MA, Liu Y, Kraft P, Richards JE, Rosner BA, Hauser MA, Hauser MA, Klaver CCW, van Duijn CM, Haines J, Wiggs JL, Pasquale LR. Genetic correlations between intraocular pressure, blood pressure and primary open-angle glaucoma: a multi-cohort analysis. Eur J Hum Genet 2017;25(11):1261-1267.Abstract
Primary open-angle glaucoma (POAG) is the most common chronic optic neuropathy worldwide. Epidemiological studies show a robust positive relation between intraocular pressure (IOP) and POAG and modest positive association between IOP and blood pressure (BP), while the relation between BP and POAG is controversial. The International Glaucoma Genetics Consortium (n=27 558), the International Consortium on Blood Pressure (n=69 395), and the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database (n=37 333), represent genome-wide data sets for IOP, BP traits and POAG, respectively. We formed genome-wide significant variant panels for IOP and diastolic BP and found a strong relation with POAG (odds ratio and 95% confidence interval: 1.18 (1.14-1.21), P=1.8 × 10-27) for the former trait but no association for the latter (P=0.93). Next, we used linkage disequilibrium (LD) score regression, to provide genome-wide estimates of correlation between traits without the need for additional phenotyping. We also compared our genome-wide estimate of heritability between IOP and BP to an estimate based solely on direct measures of these traits in the Erasmus Rucphen Family (ERF; n=2519) study using Sequential Oligogenic Linkage Analysis Routines (SOLAR). LD score regression revealed high genetic correlation between IOP and POAG (48.5%, P=2.1 × 10-5); however, genetic correlation between IOP and diastolic BP (P=0.86) and between diastolic BP and POAG (P=0.42) were negligible. Using SOLAR in the ERF study, we confirmed the minimal heritability between IOP and diastolic BP (P=0.63). Overall, IOP shares genetic basis with POAG, whereas BP has limited shared genetic correlation with IOP or POAG.
Di Zazzo A, Roberti G, Mashaghi A, Abud TB, Pavese D, Bonini S. Use of Topical Cannabinomimetic Palmitoylethanolamide in Ocular Surface Disease Associated with Antiglaucoma Medications. J Ocul Pharmacol Ther 2017;33(9):670-677.Abstract
PURPOSE: Chronic use of topical hypotensive therapies in glaucoma patients leads to chronic inflammation of the ocular surface, which decreases the success rate of long-term glaucoma management. The aim of this study is to evaluate the effect of topical palmitoylethanolamide (PEA) (Defluxa©), a well-known anti-inflammatory and analgesic agent, in suppressing the ocular surface inflammation associated with the use of hypotensive eye drops. METHODS: In a pilot clinical trial, we enrolled 15 glaucomatous patients who received topical PEA (Defluxa) in addition to the current antiglaucoma drugs, while 15 glaucomatous patients did not receive any additional treatment. At 3 different time points (day 0, 15, and 30), signs of ocular surface involvement, adverse events, visual acuity, and intraocular pressure were assessed. RESULTS: Topical PEA (Defluxa) was effective in increasing the Schirmer test (P < 0.05) and the tear film breakup time (T-BUT) (P < 0.0001), and improving the conjunctival hyperemia (P < 0.0001) by day 30, compared to baseline. Compared to control, by day 15, the conjunctival hyperemia score was significantly decreased in the PEA (Defluxa) group (P < 0.01), while the T-BUT and the Schirmer Test achieved a significant improvement by day 30 (P < 0.05; P < 0.01). DISCUSSION: Our data suggests that topical PEA (Defluxa) is a safe, effective, and generally well-tolerated treatment to prevent or suppress ocular surface inflammation attributable to chronic glaucoma treatment.
Foulsham W, Tatham AJ. High Altitude-associated Changes in Intraocular Pressure Abrogated by Trabeculectomy. J Glaucoma 2017;26(10):957-960.Abstract
PURPOSE: To highlight the effect of ascent to high altitude on intraocular pressure (IOP) in a patient with primary open-angle glaucoma, who had previously undergone trabeculectomy in 1 eye. METHODS: Case report. RESULTS: A 66-year-old mountaineer with primary open-angle glaucoma and previous right trabeculectomy performed self-tonometry using a rebound tonometer (Icare HOME) before and during an expedition in the Himalaya. In the nonoperated eye, there was a statistically significant increase in IOP as the patient ascended to 5000 m over 8 days (R=0.790, P=0.001), consistent with recent literature. IOP increased by 1.73 mm Hg with each 1000 m increase in altitude. In the trabeculectomized eye there was no significant increase in IOP (R=0.219, P=0.172). CONCLUSIONS: Filtration surgery may be protective against IOP fluctuations associated with ascent to high altitude. Self-tonometry complements standard glaucoma care by providing opportunities for IOP monitoring outside office hours and in remote locations.
Khoueir Z, Jassim F, Poon LY-C, Tsikata E, Ben-David GS, Liu Y, Shieh E, Lee R, Guo R, Papadogeorgou G, Braaf B, Simavli H, Que C, Vakoc BJ, Bouma BE, de Boer JF, Chen TC. Diagnostic Capability of Peripapillary Three-dimensional Retinal Nerve Fiber Layer Volume for Glaucoma Using Optical Coherence Tomography Volume Scans. Am J Ophthalmol 2017;182:180-193.Abstract
PURPOSE: To determine the diagnostic capability of peripapillary 3-dimensional (3D) retinal nerve fiber layer (RNFL) volume measurements from spectral-domain optical coherence tomography (OCT) volume scans for open-angle glaucoma (OAG). DESIGN: Assessment of diagnostic accuracy. METHODS: Setting: Academic clinical setting. STUDY POPULATION: Total of 180 patients (113 OAG and 67 normal subjects). OBSERVATION PROCEDURES: One eye per subject was included. Peripapillary 3D RNFL volumes were calculated for global, quadrant, and sector regions, using 4 different-size annuli. Peripapillary 2D RNFL thickness circle scans were also obtained. MAIN OUTCOME MEASURES: Area under the receiver operating characteristic curve (AUROC) values, sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios. RESULTS: Among all 2D and 3D RNFL parameters, best diagnostic capability was associated with inferior quadrant 3D RNFL volume of the smallest annulus (AUROC value 0.977). Otherwise, global 3D RNFL volume AUROC values were comparable to global 2D RNFL thickness AUROC values for all 4 annulus sizes (P values: .0593 to .6866). When comparing the 4 annulus sizes for global RNFL volume, the smallest annulus had the best AUROC values (P values: .0317 to .0380). The smallest-size annulus may have the best diagnostic potential, partly owing to having no areas excluded for being larger than the 6 × 6 mm(2) scanned region. CONCLUSION: Peripapillary 3D RNFL volume showed excellent diagnostic performance for detecting glaucoma. Peripapillary 3D RNFL volume parameters have the same or better diagnostic capability compared to peripapillary 2D RNFL thickness measurements, although differences were not statistically significant.
Hark LA, Katz JL, Myers JS, Waisbourd M, Johnson D, Pizzi LT, Leiby BE, Fudemberg SJ, Mantravadi AV, Henderer JD, Zhan T, Molineaux J, Doyle V, Divers M, Burns C, Murchison AP, Reber S, Resende A, Bui TDV, Lee J, Crews JE, Saaddine JB, Lee PP, Pasquale LR, Haller JA. Philadelphia Telemedicine Glaucoma Detection and Follow-up Study: Methods and Screening Results. Am J Ophthalmol 2017;181:114-124.Abstract
PURPOSE: To describe methodology and screening results from the Philadelphia Telemedicine Glaucoma Detection and Follow-up Study. DESIGN: Screening program results for a prospective randomized clinical trial. METHODS: Individuals were recruited who were African-American, Hispanic/Latino, or Asian over age 40 years; white individuals over age 65 years; and any ethnicity over age 40 years with a family history of glaucoma or diabetes. Primary care offices and Federally Qualified Health Centers were used for telemedicine (Visit 1). Two posterior fundus photographs and 1 anterior segment photograph were captured per eye in each participant, using a nonmydriatic, autofocus, hand-held fundus camera (Volk Optical, Mentor, Ohio, USA). Medical and ocular history, family history of glaucoma, visual acuity, and intraocular pressure measurements using the ICare rebound tonometer (ICare, Helsinki, Finland) were obtained. Images were read remotely by a trained retina reader and a glaucoma specialist. RESULTS: From April 1, 2015, to February 6, 2017, 906 individuals consented and attended Visit 1. Of these, 553 participants were female (61.0%) and 550 were African-American (60.7%), with a mean age of 58.7 years. A total of 532 (58.7%) participants had diabetes, and 616 (68%) had a history of hypertension. During Visit 1, 356 (39.3%) participants were graded with a normal image. Using image data from the worse eye, 333 (36.8%) were abnormal and 155 (17.1%) were unreadable. A total of 258 (28.5%) had a suspicious nerve, 62 (6.8%) had ocular hypertension, 102 (11.3%) had diabetic retinopathy, and 68 (7.5%) had other retinal abnormalities. CONCLUSION: An integrated telemedicine screening intervention in primary care offices and Federally Qualified Health Centers detected high rate of suspicious optic nerves, ocular hypertension, and retinal pathology.

Pages