BioXTAS RAW: improvements to a free open-source program for small-angle X-ray scattering data reduction and analysis.

PubMed

Hopkins, Jesse Bennett; Gillilan, Richard E; Skou, Soren

2017-10-01

BioXTAS RAW is a graphical-user-interface-based free open-source Python program for reduction and analysis of small-angle X-ray solution scattering (SAXS) data. The software is designed for biological SAXS data and enables creation and plotting of one-dimensional scattering profiles from two-dimensional detector images, standard data operations such as averaging and subtraction and analysis of radius of gyration and molecular weight, and advanced analysis such as calculation of inverse Fourier transforms and envelopes. It also allows easy processing of inline size-exclusion chromatography coupled SAXS data and data deconvolution using the evolving factor analysis method. It provides an alternative to closed-source programs such as Primus and ScÅtter for primary data analysis. Because it can calibrate, mask and integrate images it also provides an alternative to synchrotron beamline pipelines that scientists can install on their own computers and use both at home and at the beamline.

Monte Carlo-based assessment of the trade-off between spatial resolution, field-of-view and scattered radiation in the variable resolution X-ray CT scanner.

PubMed

Arabi, Hossein; Kamali Asl, Ali Reza; Ay, Mohammad Reza; Zaidi, Habib

2015-07-01

The purpose of this work is to evaluate the impact of optimization of magnification on performance parameters of the variable resolution X-ray (VRX) CT scanner. A realistic model based on an actual VRX CT scanner was implemented in the GATE Monte Carlo simulation platform. To evaluate the influence of system magnification, spatial resolution, field-of-view (FOV) and scatter-to-primary ratio of the scanner were estimated for both fixed and optimum object magnification at each detector rotation angle. Comparison and inference between these performance parameters were performed angle by angle to determine appropriate object position at each opening half angle. Optimization of magnification resulted in a trade-off between spatial resolution and FOV of the scanner at opening half angles of 90°-12°, where the spatial resolution increased up to 50% and the scatter-to-primary ratio decreased from 4.8% to 3.8% at a detector angle of about 90° for the same FOV and X-ray energy spectrum. The disadvantage of magnification optimization at these angles is the significant reduction of the FOV (up to 50%). Moreover, magnification optimization was definitely beneficial for opening half angles below 12° improving the spatial resolution from 7.5 cy/mm to 20 cy/mm. Meanwhile, the FOV increased by more than 50% at these angles. It can be concluded that optimization of magnification is essential for opening half angles below 12°. For opening half angles between 90° and 12°, the VRX CT scanner magnification should be set according to the desired spatial resolution and FOV. Copyright © 2015 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

A comparison of latanoprost monotherapy with a combination therapy of timolol/dorzolamide in patients with primary open-angle glaucoma.

PubMed

Caça, Ihsan; Simsek, Hüseyin; Unlü, Kaan; Ari, Seyhmus; Keklikçi, Ugur

2006-01-01

We compared latanoprost monotherapy therapy with timolol/ dorzolamide in patients with primary open-angle glaucoma to evaluate the effects on intraocular pressure (IOP) and occurrence of adverse events. IOP and topical side effects were evaluated at the beginning, first, and third months. Mean IOP was decreased at the third month. The most common side effect was hyperemia (43.6%). We concluded that latanoprost reduces IOP better than fixed combination and its topical side effects are tolerable.

Retinoschisis and neurosensory detachment in advanced focal glaucoma.

PubMed

Arranz-Márquez, E; Jarrín Hernández, E; Pastor, A; García Gil de Bernabé, J

2017-10-01

A 71-year-old woman with normotensive primary open-angle glaucoma presented with an asymptomatic temporal peripapillary retinoschisis, associated with serous retinal detachment in the eye with the more advanced glaucoma. It was located at the inferior pole of the optic disc, in the proximity of a glaucomatous focal disc defect. Although congenital optic pits are strongly related with juxta-papillary retinoschisis, retinoschisis can also arise from acquired defects in the proximity of glaucomatous optic discs. As symptoms depend on the extent of the retinoschisis, the prevalence of this complication could be greater than that reported in glaucomatous eyes. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Ocular surface disease incidence in patients with open-angle glaucoma.

PubMed

Radenković, Marija; Stanković-Babić, Gordana; Jovanović, Predrag; Djordjević-Jocić, Jasmina; Trenkić-Božinović, Marija

2016-01-01

Ocular surface disease (OSD) is a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbances, tear film instability with potential damage to the ocular surface, accompanied by increased tear film osmolarity and inflammation of the ocular surface. It is a consequence of disrupted homeostasis of lacrimal functional unit. The main pathogenetic mechanism stems from tear hyperosmolarity and tear film instability. The etiological classification is hyposecretory (Sy-Sjögren and non-Sjögren) and evaporative (extrinsic and intrinsic) form. Delphi panel classification grades disease stages. Antiglaucoma topical therapy causes exacerbation or occurrence of symptoms of dry eye due to main ingredients or preservatives (benzalkonium chloride – BAK), which are dose- and time-dependent. BAK reduces the stability of the lipid layer of tears, the number of goblet cells, induces apoptosis and inflammatory infiltration. The aim of this study was the analysis of the OSD incidence in open-angle glaucoma patients caused by topical medicamentous therapy. Retrospective analysis of examined patients with open-angle glaucoma was used. Increased incidence of moderate and advanced OSD Index degrees in the group of primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma. According to the Delphi Panel Scale the most common grade is IIb (POAG and pseudoexfoliative glaucoma). Evaporative form of OSD prevailed in all treatment groups. High percentage of dry eye in patients with higher concentrations of preservatives applied was noticed. OSD should be timely diagnosed and treated. Dry eye has an impact on surgical outcome and postoperative visual acuity, and in order to improve patient compliance and quality of life, symptoms of dry eye should be addressed and medications with lower concentrations of preservatives should be applied.

Evaluation of blotchy pigments in the anterior chamber angle as a sign of angle closure

PubMed Central

Rao, Harsha L; Mungale, Sachin C; Kumbar, Tukaram; Parikh, Rajul S; Garudadri, Chandra S

2012-01-01

Background: Blotchy pigments in the anterior chamber (AC) angle are considered diagnostic of primary angle closure (PAC). But there are no reports either on the prevalence of blotchy pigments in AC angles or the validity of this sign. Aims: To determine the prevalence of blotchy pigments in AC angles and to evaluate their relationship with glaucomatous optic neuropathy (GON) in eyes with occludable angles. Setting and Design: Cross-sectional, comparative study. Materials and Methods: Gonioscopy was performed in 1001 eyes of 526 subjects (245 eyes of 148 consecutive, occludable angle subjects and 756 eyes of 378 non-consecutive, open angle subjects), above 35 years of age. Quadrant-wise location of blotchy pigments was documented. Statistical Analysis: Odds of blotchy pigments in occludable angles against that in open angles were evaluated. Relationship of GON with blotchy pigments in occludable angle eyes was evaluated using a multivariate model. Results: Prevalence of blotchy pigments in occludable angles was 28.6% (95% CI, 22.9-34.3) and in open angles was 4.7% (95% CI, 3.2-6.3). Blotchy pigments were more frequently seen in inferior (16%) and superior quadrants (15%) of occludable angles, and inferior quadrant of open angles (4%). Odds of superior quadrant blotchy pigments in occludable angles were 33 times that in open angles. GON was seen in 107 occludable angle eyes. Blotchy pigments were not significantly associated with GON (odds ratio = 0.5; P = 0.1). Conclusions: Blotchy pigments were seen in 28.6% of occludable angle eyes and 4.7% of open angles eyes. Presence of blotchy pigments in the superior quadrant is more common in occludable angles. Presence of GON in occludable angle eyes was not associated with blotchy pigments. PMID:23202393

Assessment of preoperative nutritional status using BIA-derived phase angle (PhA) in patients with advanced ovarian cancer: Correlation with the extent of cytoreduction and complications.

PubMed

Uccella, Stefano; Mele, Maria Cristina; Quagliozzi, Lorena; Rinninella, Emanuele; Nero, Camilla; Cappuccio, Serena; Cintoni, Marco; Gasbarrini, Antonio; Scambia, Giovanni; Fagotti, Anna

2018-05-01

To investigate whether patients' altered body composition (measured with bioimpedentiometry), due to a poor nutritional status, predicts the incidence of no residual disease at primary debulking and the risk of complications in patients with newly-diagnosed advanced epithelial ovarian cancer (EOC). Data regarding patients with newly-diagnosed stage IIIC-IV EOC undergoing elective nutritional assessment between December 2016 and March 2017, were prospectively collected. Bioelectrical impedance analysis (BIA) with measurement of BIA-derived phase angle [PhA] at 50KHz, was accomplished. Only patients with disease which was considered resectable at staging laparoscopy were submitted to open primary cytoreduction. The rate of residual tumor (RT)=0 and the incidence of complications were assessed. Seventy patients were included. Fifty-two of them were submitted to primary cytoreduction (74.3%) and 48 (68.6% of the entire cohort, 92.3% of those who underwent primary debulking) had RT=0 at the end of surgery. Median values of PhA were significantly lower in patients with RT>vs. =0 (4.7, range: 3.6-5.8 vs. 5.3, range: 4.2-6.8; p=0.001). Twenty-four (out of the 52 operated) patients (46.2%) developed at least one complication. PhA was significantly lower in patients with vs. without complications (5, range: 3.6-6.4, vs. 5.4, range 4.5-6.8; p=0.03). After multivariable analysis, Fagotti score and PhA were the only independent predictors of residual disease (OR:13.56; 95%CI:1.33-137.6; p=0.027 and 9.24; 1.16-73.43; p=0.036, respectively) and of any complication (OR:4.9;95%CI:1.17-20.6; p=0.03 and 7.27; 1.45-36.4; p=0.01, respectively). Derangement of body composition (likely due to disease-related malnutrition) expressed as a low phase angle, is an independent predictor of residual disease and peri-operative complications at the time of upfront cytoreduction for advanced EOC. Copyright © 2018 Elsevier Inc. All rights reserved.

[The effectiveness of endonasal electrophoresis of neuroprotective agents used in the rehabilitative treatment of the patients presenting with primary open angle glaucoma].

PubMed

Nazarova, G A; Konchugova, T V; Iurova, O V; Sichinava, N V; Turova, E A; Rassulova, M A; Morozova, N E

2013-01-01

The objective of the present study was to estimate the effectiveness of the peptide drug cortexin used to treat primary open angle glaucoma. It was shown that endonasal electrophoresis of cortexin resulted in more pronounced positive changes in the dynamics of clinical, functional, perimetric, and electrophysiological characteristics compared with intramuscular administration of the same drug to the patients of the control group. This difference was apparent both immediately after the termination of the treatment and during the long-term follow-up.

[Thinking about the present primary open angle glaucoma early diagnosis concepts and methods].

PubMed

Ren, Zeqin

2014-05-01

Early diagnosis of primary open-angle glaucoma has not been clear and consistent in concepts and methods. At present, according to the pathophysiology process of optic nerve damage and its detection technology, early diagnosis on the concept still belongs to the early clinical diagnosis instead of preclinical diagnosis, and on the method depends on the fundus as morphological index combined with the visual field as functional index. The direction of early clinical diagnosis mainly lies in exploring more effective diagnosis index, rather than blindly adopt new diagnostic technology.

Juxtacanalicular tissue in pigmentary and primary open angle glaucoma. The hydrodynamic role of pigment and other constituents.

PubMed

Murphy, C G; Johnson, M; Alvarado, J A

1992-12-01

We tested the hypothesis that obstruction of the juxtacanalicular tissues, by melanin granules in pigmentary glaucoma and by other impermeable material in primary open angle glaucoma, leads to the development of a chronic glaucomatous condition. The distribution and concentration of melanin and other impermeable materials in the juxtacanalicular tissues and elsewhere in the trabecular meshwork was determined in 13 specimens. Six specimens were from patients with pigmentary glaucoma, two from patients with pigment dispersion syndrome, and three from patients with primary open angle glaucoma, as well as two from normal subjects. The effect of these materials on flow resistance was estimated using two hydrodynamic models. In model A, the electron-lucent spaces of the juxtacanalicular tissue were assumed to be open spaces, while in model B, these spaces and spaces filled with ground substance were assumed to be gel filled. In pigmentary glaucoma, 3.5% of the pigment was found in the juxtacanalicular tissue, while 96.5% was found in the corneoscleral and uveoscleral tissues. Permeabilities calculated according to model A were much higher than those expected from estimates of outflow facility in all groups, in agreement with the previous report of Ethier et al. The gel-filled spaces available for fluid flow, as determined by model B, showed no statistically demonstrable differences (pigmentary glaucoma, 32.9%; primary open angle glaucoma, 36.6%; pigment dispersion syndrome, 43.4%; normal, 44.1%). Furthermore, the amount of pigment present in the juxtacanalicular tissue was determined to have a negligible influence on permeability. Thus, the development of the chronic glaucomatous condition cannot be directly attributed to pigment accumulation in the juxtacanalicular tissue in pigmentary glaucoma.

Linkage studies in primary open angle glaucoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Avramopoulos, D.; Grigoriadu, M.; Kitsos, G.

1994-09-01

Glaucoma is a leading cause of blindness worldwide. The majority of glaucoma is associated with an open, normal appearing anterior chamber angle and is termed primary open angle glaucoma (POAG, MIM 137760). It is characterized by elevated intraocular pressure and onset in middle age or later. A subset of POAG with juvenile onset has recently been linked to chromosome 1q in two families with autosomal dominant inheritance. Eleven pedigrees with autosomal dominant POG (non-juvenile-onset) have been identified in Epirus, Greece. In the present study DNA samples have been collected from 50 individuals from one large pedigree, including 12 affected individuals.more » Preliminary results of linkage analysis with chromosome 1 microsatellites using the computer program package LINKAGE Version 5.1 showed no linkage with the markers previously linked to juvenile-onset POAG. Further linkage analysis is being pursued, and the results will be presented.« less

Visual Disability Among Juvenile Open-angle Glaucoma Patients.

PubMed

Gupta, Viney; Ganesan, Vaitheeswaran L; Kumar, Sandip; Chaurasia, Abadh K; Malhotra, Sumit; Gupta, Shikha

2018-04-01

Juvenile onset primary open-angle glaucoma (JOAG) unlike adult onset primary open-angle glaucoma presents with high intraocular pressure and diffuse visual field loss, which if left untreated leads to severe visual disability. The study aimed to evaluate the extent of visual disability among JOAG patients presenting to a tertiary eye care facility. Visual acuity and perimetry records of unrelated JOAG patients presenting to our Glaucoma facility were analyzed. Low vision and blindness was categorized by the WHO criteria and percentage impairment was calculated as per the guidelines provided by the American Medical Association (AMA). Fifty-two (15%) of the 348 JOAG patients were bilaterally blind at presentation and 32 (9%) had low vision according to WHO criteria. Ninety JOAG patients (26%) had a visual impairment of 75% or more. Visual disability at presentation among JOAG patients is high. This entails a huge economic burden, given their young age and associated social responsibilities.

Comparison between visual field defect in pigmentary glaucoma and primary open-angle glaucoma.

PubMed

Nilforushan, Naveed; Yadgari, Maryam; Jazayeri, Anisalsadat

2016-10-01

To compare visual field defect patterns between pigmentary glaucoma and primary open-angle glaucoma. Retrospective, comparative study. Patients with diagnosis of primary open-angle glaucoma (POAG) and pigmentary glaucoma (PG) in mild to moderate stages were enrolled in this study. Each of the 52 point locations in total and pattern deviation plot (excluding 2 points adjacent to blind spot) of 24-2 Humphrey visual field as well as six predetermined sectors were compared using SPSS software version 20. Comparisons between 2 groups were performed with the Student t test for continuous variables and the Chi-square test for categorical variables. Thirty-eight eyes of 24 patients with a mean age of 66.26 ± 11 years (range 48-81 years) in the POAG group and 36 eyes of 22 patients with a mean age of 50.52 ± 11 years (range 36-69 years) in the PG group were studied. (P = 0.00). More deviation was detected in points 1, 3, 4, and 32 in total deviation (P = 0.03, P = 0.015, P = 0.018, P = 0.023) and in points 3, 4, and 32 in pattern deviation (P = 0.015, P = 0.049, P = 0.030) in the POAG group, which are the temporal parts of the field. It seems that the temporal area of the visual field in primary open-angle glaucoma is more susceptible to damage in comparison with pigmentary glaucoma.

Progressive Decrease of Peripapillary Angioflow Vessel Density During Structural and Visual Field Progression in Early Primary Open-angle Glaucoma.

PubMed

Holló, Gábor

2017-07-01

To present a case of early primary open-angle glaucoma in which retinal nerve fiber layer thickness (RNFLT), ganglion cell complex (GCC), and visual field progression were accompanied with significant progression of peripapillary angioflow vessel density (PAFD) measured with optical coherence tomographic angiography. A 68-year-old female patient who was under topical intraocular pressure (IOP) lowering medication for 20 years for ocular hypertension of the right and preperimetric primary open-angle glaucoma of the left eye (with reproducible inferotemporal and superotemporal neuroretinal rim and RNFL loss) was prospectively imaged with the AngioVue OCT for RNFLT, GCC thickness, and PAFD, and investigated with the Octopus Normal G2 visual field test on the same days at 6-month intervals for 18 months, while the IOP of the left eye escaped from control. IOP of the left eye fluctuated between 14 and 30 mm Hg in the study period. RNFLT, GCC thickness, and peripapillary PAFD all decreased significantly (linear regression analysis, P=0.030, 0.040, and 0.020, respectively), and a significant 2.1 dB/y progression was seen for a superior visual field cluster. The RNFLT, peripapillary PAFD, and visual field of the right eye remained normal and unchanged. In our case IOP elevation, glaucomatous visual field conversion, and structural progression were accompanied with significant progressive decrease of peripapillary PAFD. The simultaneous thinning of RNFLT and GCC and decrease of peripapillary PAFD suggest that PAFD may potentially be an additional indicator of early progression in primary open-angle glaucoma.

Macular Thickness Variability in Primary Open Angle Glaucoma Patients using Optical Coherence Tomography

PubMed Central

Agarwal, Prakashchand; Sathyan, P; Saini, VK

2014-01-01

ABSTRACT Aim: To compare the difference of retinal macular thickness and macular volume using optical coherence tomography (OCT) in primary open angle glaucoma (POAG) patients with the normal subjects. Materials and methods: This observational case control study included primary open angle glaucoma (POAG) patients (n = 124 eyes) and healthy subjects in the control group (n = 124 eyes). All subjects underwent detailed history, general and systemic exami -nation. Complete ocular examination included best corrected visual acuity (BCVA), slit lamp examination, intraocular pressure (IOP), central corneal thickness, gonioscopy, dilated fundus biomicroscopy. Field analysis was done by white on white Humphrey Field Analyzer (Carl Zeiss). Optical coherence tomography imaging of macular area was performed using Stratus OCT (OCT 3, Version 4, Carl Zeiss Inc, Dublin, California, USA). In both these groups, parameters analyzed were macular thickness, inner macular thicknesses (IMT), outer macular thicknesses (OMT), central macular thick ness (CMT) and total macular volume (TMV). Results: The POAG group had significantly decreased values of TMV, OMT and IMT, compared to control group, while there was no difference in CMT, presumably due to absence of ganglion cells in the central part. Thus, macular thickness and volume parameters may be used for making the diagnosis of glaucoma especially in patients with abnormalities of disc. Conclusion: Macular thickness parameters correlated well with the diagnosis of glaucoma. How to cite this article: Sharma A, Agarwal P, Sathyan P, Saini VK. Macular Thickness Variability in Primary Open Angle Glaucoma Patients using Optical Coherence Tomography. J Current Glau Prac 2014;8(1):10-14. PMID:26997801

Glymphatic stasis at the site of the lamina cribrosa as a potential mechanism underlying open-angle glaucoma.

PubMed

Wostyn, Peter; Killer, Hanspeter Esriel; De Deyn, Peter Paul

2017-07-01

The underlying pathophysiology of primary open-angle glaucoma remains unclear, but the lamina cribrosa seems to be the primary site of injury, and raised intraocular pressure is a major risk factor. In recent years, a decreased intracranial pressure, leading to an abnormally high trans-lamina cribrosa pressure difference, has gained interest as a new risk factor for glaucoma. New research now lends support to the hypothesis that a paravascular transport system is present in the eye analogous to the recently discovered 'glymphatic system' in the brain, which is a functional waste clearance pathway that promotes elimination of interstitial solutes, including β-amyloid, from the brain along paravascular channels. Given that β-amyloid has been reported to increase by chronic elevation of intraocular pressure in glaucomatous animal models and to cause retinal ganglion cell death, the discovery of a paravascular clearance system in the eye may provide powerful new insights into the pathophysiology of primary open-angle glaucoma. In this review, we provide a new conceptual framework for understanding the pathogenesis of primary open-angle glaucoma, present supporting preliminary data from our own post-mortem study and hypothesize that the disease may result from restriction of normal glymphatic flow at the level of the lamina cribrosa owing to a low intracranial pressure and/or a high trans-lamina cribrosa pressure gradient. If confirmed, this viewpoint could offer new perspectives for the development of novel diagnostic and therapeutic strategies for this devastating disorder. © 2017 Royal Australian and New Zealand College of Ophthalmologists.

Gonioscopy-assisted Transluminal Trabeculotomy: An Ab Interno Circumferential Trabeculotomy: 24 Months Follow-up.

PubMed

Grover, Davinder S; Smith, Oluwatosin; Fellman, Ronald L; Godfrey, David G; Gupta, Aditi; Montes de Oca, Ildamaris; Feuer, William J

2018-05-01

The purpose of this study was to provide 24-month follow-up on surgical success and safety of an ab interno circumferential 360-degree trabeculotomy. Chart review of patients who underwent a gonioscopy-assisted transluminal trabeculotomy (GATT) procedure was performed by 4 of the authors (D.S.G., O.S., R.L.F., and D.G.G.). The surgery was performed in adults with various types of open-angle glaucoma with preoperative intraocular pressures (IOPs) of ≥18 mm Hg. In total, 198 patients aged 24 to 89 years underwent the GATT procedure with at least 18 months follow-up. Patients with primary open-angle glaucoma had an average IOP decrease of 9.2 mm Hg at 24 months with an average decrease of 1.43 glaucoma medications. The mean percentage of IOP decrease in these primary open-angle glaucoma groups at 24 months was 37.3%. In secondary open-angle glaucoma, at 24 months there was an average decrease in IOP of 14.1 mm Hg on an average of 2.0 fewer medications. The mean percentage of IOP decrease in the secondary open-angle glaucoma groups at 24 months was 49.8%. The cumulative proportion of failure at 24 months ranged from 0.18 to 0.48, depending on the group. In all 6 study groups, at all 5 postoperative time points (3, 6, 12, 18, and 24 mo) the mean IOP and reduction in glaucoma medications was significantly reduced from baseline (P<0.001) with the exception of one time point. The 24-month results demonstrate that GATT is relatively safe and effective in treating various forms of open-angle glaucoma. The long-term results for GATT are relatively equivalent to those previously reported for GATT and ab externo trabeculotomy studies.

[Results of the ocular hypertension treatment study and the confocal scanning laser ophthalmoscopy ancillary study and evaluation of the heidelberg retina tomograph].

PubMed

Klatt, K; Schmidt, E; Scheuerle, A F

2008-04-01

The Ocular Hypertension Treatment Study (OHTS) has shown that analyzing changes of the optic disc configuration is superior to evaluating visual field findings for the early detection of primary open angle glaucoma. The Confocal Scanning Laser Ophthalmoscopy Ancillary Study (CSLO) is the first study to reveal that certain topographic baseline measurements of the optic disc are significantly associated with the development of primary open angle glaucoma in patients with ocular hypertension. An abnormally increased "mean height contour" value proved to be the individual parameter connected with the highest risk. The reliability of the Moorfields Regression Analysis of certain individual sectors during early detection of a primary angle glaucoma is higher than that of the global measurement. The temporal superior and inferior as well as the nasal inferior sectors have the highest positive predictive values and the largest risks in both univariate and multivariate analysis.

The Frequency of Optical Coherence Tomography Testing in Glaucoma at a Single Academic Medical Center.

PubMed

Griffith, Joseph F; Goldberg, Jeffrey L

2016-03-01

To determine the frequency of optical coherence tomography (OCT) examinations compared with clinical examinations and visual field (VF) tests in patients with 5 types of glaucoma. A retrospective, longitudinal cohort study was conducted of 5154 patients treated between 2003 and 2010 at a single academic medical center. Patients were classified using billing records as having primary open-angle glaucoma, low-tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic angle-closure glaucoma, or pseudoexfoliation glaucoma. Analysis of variance, χ test, and exact χ test were performed to identify associations between glaucoma type and test frequency. Pigmentary open-angle glaucoma and NTG patients had a higher rate of undergoing at least 2 VFs (94.4%, 94.9%), and chronic angle-closure glaucoma patients had a lower rate of undergoing at least 2 OCTs (25.3%) than all other glaucoma types. NTG patients also had the highest rate of undergoing at least 2 OCTs and at least 2 VFs (36.6%). Overall, the rate of clinical examinations (2.68 examinations/y) exceeded the rates of OCTs (1.39 examinations/y), which exceeded the rate of VF tests (1.24 tests/y). There were no differences in OCT frequency between glaucoma types (0.91 to 1.63 OCTs/y). Within each glaucoma diagnosis, patients had clinical examinations more frequently than OCTs and clinical examinations more frequently than VFs. Primary open-angle glaucoma and pseudoexfoliation glaucoma patients also had OCTs more frequently than VFs. More patients had at least 2 VF tests than at least 2 OCTs (4481 vs. 1679). The relative use of clinical examinations, VF testing, and OCT imaging varies among glaucoma diagnoses.

Detection of primary angle closure using anterior segment optical coherence tomography in Asian eyes.

PubMed

Nolan, Winifred P; See, Jovina L; Chew, Paul T K; Friedman, David S; Smith, Scott D; Radhakrishnan, Sunita; Zheng, Ce; Foster, Paul J; Aung, Tin

2007-01-01

To evaluate noncontact anterior segment optical coherence technology (AS-OCT) as a qualitative method of imaging the anterior chamber angle and to determine its ability to detect primary angle closure when compared with gonioscopy in Asian subjects. Prospective observational case series. Two hundred three subjects were recruited from glaucoma clinics in Singapore with diagnoses of primary angle closure, primary open-angle glaucoma, ocular hypertension, or cataract. Both eyes (if eligible) of each patient were included in the study. Exclusion criteria were pseudophakia or previous glaucoma surgery. Images of the nasal, temporal, and inferior angles were obtained with AS-OCT in dark and then light conditions. Gonioscopic angle width was graded using the Spaeth classification for each quadrant in low lighting conditions. Angle closure was defined by AS-OCT as contact between the peripheral iris and angle wall anterior to the scleral spur and by gonioscopy as a Spaeth grade of 0 degree (posterior trabecular meshwork not visible). Comparison of the 2 methods in detecting angle closure was done by eye and by individual. Sensitivities and specificities of AS-OCT were calculated using gonioscopy as the reference standard. Complete data were available for 342 eyes of 200 patients. Of the patients, 70.9% had a clinical diagnosis of treated or untreated primary angle closure. Angle closure in > or =1 quadrants was detected by AS-OCT in 142 (71%) patients (228 [66.7%] eyes) and by gonioscopy in 99 (49.5%) patients (152 [44.4%] eyes). The inferior angle was closed more frequently than the nasal or temporal quadrants using both AS-OCT and gonioscopy. When performed under dark conditions, AS-OCT identified 98% of those subjects found to have angle closure on gonioscopy (95% confidence interval [CI], 92.2-99.6) and led to the characterization of 44.6% of those found to have open angles on gonioscopy to have angle closure as well. With gonioscopy as the reference standard, specificity of AS-OCT in the dark was 55.4% (95% CI, 45.2-65.2) for detecting individuals with angle closure. Anterior segment OCT is a rapid noncontact method of imaging angle structures. It is highly sensitive in detecting angle closure when compared with gonioscopy. More persons are found to have closed angles with AS-OCT than with gonioscopy.

Are we ready for genetic testing for primary open-angle glaucoma?

PubMed

Khawaja, Anthony P; Viswanathan, Ananth C

2018-05-01

Following a dramatic reduction in the cost of genotyping technology in recent years, there have been significant advances in the understanding of the genetic basis of glaucoma. Glaucoma patients represent around a quarter of all outpatient activity in the UK hospital eye service and are a huge burden for the National Health Service. A potential benefit of genetic testing is personalised glaucoma management, allowing direction of our limited healthcare resources to the glaucoma patients who most need it. Our review aims to summarise recent discoveries in the field of glaucoma genetics and to discuss their potential clinical utility. While genome-wide association studies have now identified over ten genes associated with primary open-angle glaucoma (POAG), individually, variants in these genes are not predictive of POAG in populations. There are data suggesting some of these POAG variants are associated with conversion from ocular hypertension to POAG and visual field progression among POAG patients. However, these studies have not been replicated yet and such genetic testing is not currently justified in clinical care. In contrast, genetic testing for inherited early-onset disease in relatives of POAG patients with a known genetic mutation is of clear benefit; this can support either regular review to commence early treatment when the disease develops, or discharge from ophthalmology services of relatives who do not carry the mutation. Genetic testing for POAG at a population level is not currently justified.

Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis)

PubMed Central

Lin, Shan C.; Masis, Marisse; Porco, Travis C.; Pasquale, Louis R.

2017-01-01

Purpose To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. Methods This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. Results We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P<.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P<.001) in the wide-angle group (P=.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P<.001) reduction vs 2.5±3 mm Hg (16%, P<.001) in the wide-angle group (P=.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year (P<.05 for all). Conclusions In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option. PMID:29147104

Predictors of Intraocular Pressure After Phacoemulsification in Primary Open-Angle Glaucoma Eyes with Wide Versus Narrower Angles (An American Ophthalmological Society Thesis).

PubMed

Lin, Shan C; Masis, Marisse; Porco, Travis C; Pasquale, Louis R

2017-08-01

To assess if narrower-angle status and anterior segment optical coherence tomography (AS-OCT) parameters can predict intraocular pressure (IOP) drop in primary open-angle glaucoma (POAG) patients after cataract surgery. This was a prospective case series of consecutive cataract surgery patients with POAG and no peripheral anterior synechiae (PAS) using a standardized postoperative management protocol. Preoperatively, patients underwent gonioscopy and AS-OCT. The same glaucoma medication regimen was resumed by 1 month. Potential predictors of IOP reduction included narrower-angle status by gonioscopy and angle-opening distance (AOD500) as well as other AS-OCT parameters. Mixed-effects regression adjusted for use of both eyes and other potential confounders. We enrolled 66 eyes of 40 glaucoma patients. The IOP reduction at 1 year was 4.2±3 mm Hg (26%, P <.001) in the narrower-angle group vs 2.2±3 mm Hg (14%, P <.001) in the wide-angle group ( P =.027 for difference), as classified by gonioscopy. By AOD500 classification, the narrower-angle group had 3.4±3 mm Hg (21%, P <.001) reduction vs 2.5±3 mm Hg (16%, P <.001) in the wide-angle group ( P =.031 for difference). When the entire cohort was assessed, iris thickness, iris area, and lens vault were correlated with increasing IOP reduction at 1 year ( P <.05 for all). In POAG eyes, cataract surgery lowered IOP to a greater degree in the narrower-angle group than in the wide-angle group, and parameters relating to iris thickness and area, as well as lens vault, were correlated with IOP reduction. These findings can guide ophthalmologists in their selection of cataract surgery as a potential management option.

Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma.

PubMed

Marjanović, Ivan; Martinez, Antonio; Marjanović, Marija; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija

2013-01-01

An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP) in women and men with primary open angle glaucoma. The study included 60 patients (33 males and 27 females) older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, > 25 mm Hg).They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam) and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end-diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure.The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

Genetics Home Reference: early-onset glaucoma

MedlinePlus

... called a syndrome. If glaucoma appears before the age of 5 without other associated abnormalities, it is called primary congenital glaucoma. Other individuals experience early onset of primary open-angle glaucoma, the most ...

Trabecular Meshwork Height in Primary Open-Angle Glaucoma Versus Primary Angle-Closure Glaucoma.

PubMed

Masis, Marisse; Chen, Rebecca; Porco, Travis; Lin, Shan C

2017-11-01

To determine if trabecular meshwork (TM) height differs between primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG) eyes. Prospective, cross-sectional clinical study. Adult patients were consecutively recruited from glaucoma clinics at the University of California, San Francisco, from January 2012 to July 2015. Images were obtained from spectral-domain optical coherence tomography (Cirrus OCT; Carl Zeiss Meditec, Inc, Dublin, California, USA). Univariate and multivariate linear mixed models comparing TM height and glaucoma type were performed to assess the relationship between TM height and glaucoma subtype. Mixed-effects regression was used to adjust for the use of both eyes in some subjects. The study included 260 eyes from 161 subjects, composed of 61 men and 100 women. Mean age was 70 years (SD 11.77). There were 199 eyes (123 patients) in the POAG group and 61 eyes (38 patients) in the PACG group. Mean TM heights in the POAG and PACG groups were 812 ± 13 μm and 732 ± 27 μm, respectively, and the difference was significant in univariate analysis (P = .004) and in multivariate analysis (β = -88.7 [24.05-153.5]; P = .008). In this clinic-based population, trabecular meshwork height is shorter in PACG patients compared to POAG patients. This finding may provide insight into the pathophysiology of angle closure and provide assistance in future diagnosis, prevention, and management of the angle-closure spectrum of disorders. Copyright © 2017 Elsevier Inc. All rights reserved.

Characterizing the “POAGome”: A bioinformatics-driven approach to primary open-angle glaucoma

PubMed Central

Danford, Ian D.; Verkuil, Lana D.; Choi, Daniel J.; Collins, David W.; Gudiseva, Harini V.; Uyhazi, Katherine E.; Lau, Marisa K.; Kanu, Levi N.; Grant, Gregory R.; Chavali, Venkata R.M.; O’Brien, Joan M.

2017-01-01

Primary open-angle glaucoma (POAG) is a genetically, physiologically, and phenotypically complex neurodegenerative disorder. This study addressed the expanding collection of genes associated with POAG, referred to as the “POAGome.” We used bioinformatics tools to perform an extensive, systematic literature search and compiled 542 genes with confirmed associations with POAG and its related phenotypes (normal tension glaucoma, ocular hypertension, juvenile open-angle glaucoma, and primary congenital glaucoma). The genes were classified according to their associated ocular tissues and phenotypes, and functional annotation and pathway analyses were subsequently performed. Our study reveals that no single molecular pathway can encompass the pathophysiology of POAG. The analyses suggested that inflammation and senescence may play pivotal roles in both the development and perpetuation of the retinal ganglion cell degeneration seen in POAG. The TGF-β signaling pathway was repeatedly implicated in our analyses, suggesting that it may be an important contributor to the manifestation of POAG in the anterior and posterior segments of the globe. We propose a molecular model of POAG revolving around TGF-β signaling, which incorporates the roles of inflammation and senescence in this disease. Finally, we highlight emerging molecular therapies that show promise for treating POAG. PMID:28223208

Oxidative stress markers in patients with primary open-angle glaucoma.

PubMed

Ghanem, Asaad A; Arafa, Lamiaa F; El-Baz, Ayman

2010-04-01

To investigate the levels of antioxidant enzymes catalase (CAT), glutathione peroxidase (GPO), superoxide dismutase (SOD), and malondialdehyde (MDA) in human eyes with primary open-angle glaucoma (POAG) and to correlate their concentrations with severity of glaucoma. A prospective cases control study. Thirty patients with primary open-angle glaucoma and twenty-five patients with senile cataracts of matched age and gender were included in the study prospectively. Aqueous humor samples were obtained by paracentesis at the time of elective surgery for glaucomatous and cataractous patients. Aqueous humor were analyzed for CAT, GPO, SOD, and MDA status. GPO, SOD, and MDA enzyme levels revealed a high significant increase in aqueous humor of POAG patients with respect to the comparative group of cataract patients (P < 0.001). No significant difference in the activity of CAT enzyme in aqueous humor of POAG and cataract patient (P = 0.201). Significant correlation was found between the MDA enzyme level and severe visual field loss (P < 0.001) in POAG patients. Increased levels of aqueous humor GPO, SOD, and MDA may be associated with POAG. In addition, they may be useful antioxidant enzyme levels in aqueous humor of POAG patients as a result of glaucoma disease and not a cause.

Ocular Pseudoexfoliation and Cardiovascular Disease: A National Cross-Section Comparison Study

PubMed Central

French, Dustin D; Margo, Curtis E; Harman, Lynn E

2012-01-01

Background: Pseudoexfoliation is a systemic disorder characterized by the deposition of extracellular matrix material. The microfibrillar material that gives rise to the condition is visible clinically in the anterior segment of the eye, and is also found in other tissues, including blood vessels, skin, gallbladder, kidneys, lungs, and heart. Aims: The present study aims to determine whether ocular pseudoexfoliation is associated with selected cardiovascular diseases. Materials and Methods: A cross-section comparison study was conducted with the help of the Veterans Health Administration databases, using the International Classification of Diseases, Ninth revision, Clinical Modification for pseudoexfoliation of lens capsule and pseudoexfoliation glaucoma. Selected cardiovascular diseases and risk factors for cardiovascular disease were identified using the appropriate medical codes. Patients with primary open-angle glaucoma, chronic sinusitis, and benign prostatic hyperplasia served as the comparison groups. A logistic regression model was used to control for age, gender, race, and major cardiovascular risk factors. Results: There were 6,046 case patients with pseudoexfoliation; approximately half were diagnosed with pseudoexfoliation glaucoma. Various stages of ischemic heart disease, cardiomyopathy, and aortic aneurysm were significantly associated with ocular pseudoexfoliation, after controlling for age, gender, race, and major cardiovascular risk factors. Associations, in general, were less demonstrable relative to the primary open-angle glaucoma comparison group. Conclusion: Associations of ocular pseudoexfoliation with cardiovascular diseases were generally fewer and less pronounced when compared to patients with primary open-angle glaucoma. These results add to the results of earlier studies, which suggest that open-angle glaucoma itself might be a risk factor for certain cardiovascular disorders. PMID:23112968

Fixed combination of bimatoprost and timolol in patients with primary open-angle glaucoma or ocular hypertension with inadequate IOP adjustment

PubMed Central

Brief, Gerrett; Lammich, Tobias; Nagel, Edgar; Pfennigsdorf, Sabine; Spraul, Christoph W; Ho, Selwyn

2010-01-01

Objective To assess the efficacy and tolerability of a fixed combination of bimatoprost and timolol (BTFC) in a large patient sample in a clinical setting. Methods In this multicenter, observational, noncontrolled, open-label study, patients (n = 1862) with primary open-angle glaucoma or ocular hypertension were treated with BTFC. Assessments were made at baseline, six weeks, and three months. Results Prior to starting BTFC, 92.3% of patients were taking other ocular hypotensive medications. In the overall group at three months, mean intraocular pressure was reduced from baseline (21.7 ± 4.5 mmHg and 21.8 ± 4.9 mmHg for the right and left eye, respectively) to 16.1 ± 3.0 mmHg for each eye (P < 0.0001). The majority of patients (92%) reported no adverse events. The most commonly reported adverse events (in >1% of patients) were eye irritation, and ocular and conjunctival hyperemia. Adherence to treatment was generally better than (35.4%) or the same as (57.5%) with prior therapy. BTFC tolerability was rated as excellent or good by 92.3% of physicians and 85.8% of patients. Conclusions In a large group of patients with primary open-angle glaucoma or ocular hypertension, treatment with BTFC was associated with consistent reductions in IOP, improved adherence to treatment, and good tolerability. PMID:20957059

Exclusion of candidate genes from the chromosome 1q juvenile glaucoma region and mapping of the peripheral cannabis receptor gene (CNR2) to chromosome 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sunden, S.L.F.; Nichols, B.E.; Alward, W.L.M.

Juvenile onset primary open angle glaucoma has been mapped by linkage to 1q21-q31. Several candidate genes were evaluated in the same family used to identify the primary linkage. Atrionatriuretic peptide receptor A (NPR1) and laminin C1 (LAMC1) have been previously mapped to this region and could putatively play a role in the pathogenesis of glaucoma. A third gene, the peripheral cannabis receptor (CNR2) was not initially mapped in humans but was a candidate because of the relief that cannabis affords some patients with primary open angle glaucoma. Microsatellites associated with NPR1 and LAMC1 revealed multiple recombinations in affected members ofmore » this pedigree. CNR2 was shown to be on chromosome 1 by PCR amplification of a 150 bp fragment of the 3{prime} untranslated region in monochromosomal somatic cell hybrids (NIGMS panel No. 2). These primers also revealed a two allele single strand conformation polymorphism which showed multiple recombinants with juvenile onset primary open angle glaucoma in large pedigrees, segregating this disorder. The marker was then mapped to 1p34-p36 by linkage, with the most likely location between liver alkaline phosphatase (ALPL) and alpha-L-1 fucosidase (FUCA1).« less

Assessment of β-zone peripapillary atrophy by optical coherence tomography and scanning laser ophthalmoscopy imaging in glaucoma patients

PubMed Central

Seidensticker, Florian; Reznicek, Lukas; Mann, Thomas; Hübert, Irene; Kampik, Anselm; Ulbig, Michael; Hirneiss, Christoph; Neubauer, Aljoscha S; Kernt, Marcus

2014-01-01

Purpose To assess β-zone peripapillary atrophy (β-PPA) using spectral domain optical coherence tomography (SD-OCT), scanning laser ophthalmoscopy (SLO), and fundus auto-fluorescence (FAF) imaging in patients with primary open-angle glaucoma with advanced glaucomatous visual field defects. Methods A consecutive, prospective series of 82 study eyes with primary open-angle glaucoma were included in this study. All study participants underwent a full ophthalmic examination followed by SD-OCT, wide-field SLO, and FAF imaging of the optic nerve head and the peripapillary region. Results Eighty-four glaucomatous eyes were included in our prospective study. Correlation analyses for horizontally and vertically obtained β-PPA for all three imaging modalities (color SLO, FAF, and SD-OCT) revealed highest correlations between FAF and color SLO (Pearson correlation coefficient: 0.904 [P<0.001] for horizontal β-PPA and 0.786 [P<0.001] for vertical β-PPA). Bland–Altman plotting revealed highest agreements between color SLO and FAF, with −2.1 pixels ±1.96 standard deviation (SD) for horizontal β-PPA, SD: 10.5 pixels and 2.4 pixels ±1.96 SD for vertical β-PPA. Conclusion β-PPA can be assessed using en-face SLO and cross-sectional SD-OCT imaging. Correlation analyses revealed highest correlations between color SLO and FAF imaging, while correlations between SLO and SD-OCT were weak. A more precise structural definition of β-PPA is needed. PMID:25061270

Microvascular endothelial function and severity of primary open angle glaucoma.

PubMed

Bukhari, S M I; Kiu, K Y; Thambiraja, R; Sulong, S; Rasool, A H G; Liza-Sharmini, A T

2016-12-01

PurposeThe role of microvascular endothelial dysfunction on severity of primary open angle glaucoma (POAG) was investigated in this study.Patients and methodsA prospective cohort study was conducted. One hundred and fourteen ethnically Malay patients (114 eyes) with POAG treated at the eye clinic of Hospital University Sains Malaysia between April 2012 and December 2014 were recruited. Patients aged between 40 and 80 years with two consecutive reliable and reproducible Humphrey visual field 24-2 analyses were selected. Patients who were diagnosed with any other type of glaucoma, previous glaucoma-filtering surgery, or other surgeries except uncomplicated cataract and pterygium surgery were excluded. Humphrey visual field analysis 24-2 was used to stratify the severity of glaucoma using Advanced Glaucoma Intervention Study (AGIS) score at the time of recruitment. Microvascular endothelial function was assessed using Laser Doppler fluximetry and iontophoresis. Iontophoresis process with acetylcholine (ACh) and sodium nitroprusside (SNP) was used to measure microvascular endothelium-dependent and -independent vasodilatation, respectively.ResultsBased on the AGIS score, 55 patients showed mild glaucoma, with 29 moderate and 30 severe. There was statistically significant difference in microvascular endothelial function (ACh% and ACh max ) between mild and moderate POAG cases (P=0.023) and between mild and severe POAG cases (P<0.001). There was negative correlation between microvascular endothelial function and severity of POAG (r=-0.457, P<0.001).ConclusionMicrovascular endothelial dysfunction may have a role in influencing the severity of POAG in Malay patients.

Costs and utilization of end-stage glaucoma patients receiving visual rehabilitation care: a US multisite retrospective study.

PubMed

Gieser, David K; Tracy Williams, R; O'Connell, William; Pasquale, Louis R; Rosenthal, Bruce P; Walt, John G; Katz, Laura M; Siegartel, Lisa R; Wang, Lujing; Rosenblatt, Lisa C; Stern, Lee S; Doyle, John J

2006-10-01

Glaucoma is a prevalent ophthalmologic disease and leading cause of blindness. A retrospective analysis was conducted to evaluate resources and costs for end-stage glaucoma patients receiving visual rehabilitation care (VRC). A chart review was conducted in 3 United States VRC centers. Charts of patients with primary open-angle glaucoma as the primary cause of vision loss (1998 to 2003) were selected, yielding 81 records. Data were collected from patient-level billing and reimbursement records (ophthalmologist/optometrist visits, glaucoma medications, procedures, and specialized low-vision and glaucoma-related services). Visual rehabilitation services included utilization of low-vision devices, assessment of daily functioning, orientation and mobility training, and patient counseling. Mean age at baseline was 72.7 years [standard deviation (SD)=17.2, range: 29 to 95]. Of those with known sex (n=77), 55.8% were women. Medicare was the payer type for most patients (59.3%), whereas 20% had Medicaid. Mean number of visits was 7.1 (SD=6.1) in year 1 and 3.7 (SD=4.2) in year 2, for an annual mean of 5.4 (SD=5.0) visits overall. Total mean cost per patient in year 1 was greater than year 2 [$2170 (SD=$2252) vs. $1202 (SD=$1080), respectively]; of the total 2-year costs, 15% were VRC, 37% ophthalmology care, and 48% pharmacy. Analysis of nonpharmacy costs revealed that VRC accounted for 28% and ophthalmology for 72%. End-stage glaucoma is associated with appreciable resource utilization and costs, because of both vision rehabilitation and ophthalmology care. Advanced primary open-angle glaucoma has a substantial cost-of-illness, warranting improved management in early stages of disease.

Examining Delay Intervals in the Diagnosis and Treatment of Primary Open Angle Glaucoma in an Egyptian Population and Its Impact on Lifestyle

PubMed Central

Abu Hussein, Nahla B.; Habib, Ahmed E.; El Sayed, Yasmine M.

2016-01-01

Purpose. To examine causes as well as extent of delay in diagnosis and treatment of primary open angle glaucoma patients in a sample of Egyptians. Patients and Methods. 440 patients with primary open angle glaucoma were interviewed to evaluate delay in their diagnosis and treatment. The extent and cause of delay were investigated. The total delay interval, if any, was correlated with socioeconomic and other factors. Results. The median total delay was one year, with 50% of patients having a total delay of 1 year or less, of which 25% exhibited zero total delay. 25% of patients had a delay ranging from 1 to 3 years, and 25% had a total delay ranging from 3 to 27 years. Diagnostic delay accounted for 43.03% of cases. Longer delays were met in patients with certain socioeconomic factors. Patients with a positive family history of glaucoma displayed shorter delay periods. Conclusion. Significant delay in the diagnosis and treatment of glaucoma was found. Poor socioeconomic status seems to hinder timely diagnosis and treatment of POAG. Certain socioeconomic factors seem to correlate with the extent of delay. More effort is thus needed to subsidize the cost of investigations and treatment for glaucoma patients. PMID:28116140

Modifiable factors in the management of glaucoma: a systematic review of current evidence.

PubMed

Hecht, Idan; Achiron, Asaf; Man, Vitaly; Burgansky-Eliash, Zvia

2017-04-01

Primary open angle glaucoma is a chronic optic neuropathy affecting millions of people worldwide and represents a major public health issue. Environmental factors, behaviors, and diet are intimately related to patient health and may play a role in the pathogenesis and progression of glaucoma. This study aims to review the literature, focusing on the last three years, regarding modifiable lifestyle interventions in the management of primary open angle glaucoma. Electronic databases were searched for studies published between January 2013 and July 2016 on the topic of lifestyle interventions in primary open angle glaucoma. Sleeping with the head elevated and avoiding the worst eye-dependent side during sleep may slightly lower intraocular pressure and reduce visual field loss. Some food supplements and moderate aerobic exercise may also reduce intraocular pressure up to 2.0 and 3.0 mmHg, respectively. Frequency of coffee intake may be associated with disease progression. Potential negative effects are associated with weight-lifting and yoga exercises. Certain lifestyle habits could influence glaucoma progression, yet no specific interventions are currently supported by robust evidence. Awareness of the possible influences of certain habits should help guide clinical advice and is important to help patients avoid adverse outcomes and take an active role in the management of their disease.

Novel Automated Approach to Predict the Outcome of Laser Peripheral Iridotomy for Primary Angle Closure Suspect Eyes Using Anterior Segment Optical Coherence Tomography.

PubMed

Koh, Victor; Swamidoss, Issac Niwas; Aquino, Maria Cecilia D; Chew, Paul T; Sng, Chelvin

2018-04-27

Develop an algorithm to predict the success of laser peripheral iridotomy (LPI) in primary angle closure suspect (PACS), using pre-treatment anterior segment optical coherence tomography (ASOCT) scans. A total of 116 eyes with PACS underwent LPI and time-domain ASOCT scans (temporal and nasal cuts) were performed before and 1 month after LPI. All the post-treatment scans were classified to one of the following categories: (a) both angles open, (b) one of two angles open and (c) both angles closed. After LPI, success is defined as one or more angles changed from close to open. In this proposed method, the pre and post-LPI ASOCT scans were registered at the corresponding angles based on similarities between the respective local descriptor features and random sample consensus technique was used to identify the largest consensus set of correspondences between the pre and post-LPI ASOCT scans. Subsequently, features such as correlation co-efficient (CC) and structural similarity index (SSIM) were extracted and correlated with the success of LPI. We included 116 eyes and 91 (78.44%) eyes fulfilled the criteria for success after LPI. Using the CC and SSIM index scores from this training set of ASOCT images, our algorithm showed that the success of LPI in eyes with narrow angles can be predicted with 89.7% accuracy, specificity of 95.2% and sensitivity of 36.4% based on pre-LPI ASOCT scans only. Using pre-LPI ASOCT scans, our proposed algorithm showed good accuracy in predicting the success of LPI for PACS eyes. This fully-automated algorithm could aid decision making in offering LPI as a prophylactic treatment for PACS.

[Predicting the probability of development and progression of primary open angle glaucoma by regression modeling].

PubMed

Likhvantseva, V G; Sokolov, V A; Levanova, O N; Kovelenova, I V

2018-01-01

Prediction of the clinical course of primary open-angle glaucoma (POAG) is one of the main directions in solving the problem of vision loss prevention and stabilization of the pathological process. Simple statistical methods of correlation analysis show the extent of each risk factor's impact, but do not indicate the total impact of these factors in personalized combinations. The relationships between the risk factors is subject to correlation and regression analysis. The regression equation represents the dependence of the mathematical expectation of the resulting sign on the combination of factor signs. To develop a technique for predicting the probability of development and progression of primary open-angle glaucoma based on a personalized combination of risk factors by linear multivariate regression analysis. The study included 66 patients (23 female and 43 male; 132 eyes) with newly diagnosed primary open-angle glaucoma. The control group consisted of 14 patients (8 male and 6 female). Standard ophthalmic examination was supplemented with biochemical study of lacrimal fluid. Concentration of matrix metalloproteinase MMP-2 and MMP-9 in tear fluid in both eyes was determined using 'sandwich' enzyme-linked immunosorbent assay (ELISA) method. The study resulted in the development of regression equations and step-by-step multivariate logistic models that can help calculate the risk of development and progression of POAG. Those models are based on expert evaluation of clinical and instrumental indicators of hydrodynamic disturbances (coefficient of outflow ease - C, volume of intraocular fluid secretion - F, fluctuation of intraocular pressure), as well as personalized morphometric parameters of the retina (central retinal thickness in the macular area) and concentration of MMP-2 and MMP-9 in the tear film. The newly developed regression equations are highly informative and can be a reliable tool for studying of the influence vector and assessment of pathogenic potential of the independent risk factors in specific personalized combinations.

Differences in iris thickness among African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans.

PubMed

Lee, Roland Y; Huang, Guofu; Porco, Travis C; Chen, Yi-Chun; He, Mingguang; Lin, Shan C

2013-12-01

To evaluate the capability of iris thickness parameters to explain the difference in primary angle-closure glaucoma prevalence among the different racial groups. In this prospective study, 436 patients with open and narrow angles that met inclusion criteria were consecutively recruited from the UCSF general ophthalmology and glaucoma clinics to receive anterior segment optical coherence tomography imaging under standardized dark conditions. Images from 11 patients were removed due to poor visibility of the scleral spurs and the remaining images were analyzed using the Zhongshan Angle Assessment Program to assess the following measurements for the nasal and temporal angle of the anterior chamber: iris thickness at 750 and 2000 μm from the scleral spurs and the maximum iris thickness at middle one third of the iris. Iris thickness parameters were compared among and within the following 5 different racial groups: African Americans, Caucasian Americans, Hispanic Americans, Chinese Americans, and Filipino-Americans. In comparing iris parameters among the open-angle racial groups, significant differences were found for nasal iris thickness at 750 and 2000 μm from the scleral spurs in which Chinese Americans displayed the highest mean value (P=0.01, P<0.0001). Among the narrow-angle racial groups, significant difference was found for nasal iris thickness at 2000 μm from the scleral in which Chinese Americans showed the highest mean value (P<0.0001). Significant difference was also found for temporal maximum iris thickness at middle one third of the iris in which African Americans exhibited the highest mean value (P=0.021). Iris thickness was modeled as a function of angle status using linear mixed-effects regression, adjusting for age, sex, pupil diameter, spherical equivalent, ethnicity, and the use of both eyes in patients. The iris thickness difference between the narrow-angle and open-angle groups was significant (P=0.0007). Racial groups that historically showed higher prevalence of primary angle-closure glaucoma possess thicker irides.

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial.

PubMed

Azuara-Blanco, Augusto; Burr, Jennifer M; Cochran, Claire; Ramsay, Craig; Vale, Luke; Foster, Paul; Friedman, David; Quayyum, Zahidul; Lai, Jimmy; Nolan, Winnie; Aung, Tin; Chew, Paul; McPherson, Gladys; McDonald, Alison; Norrie, John

2011-05-23

Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care.EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible.The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events.A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. ISRCTN44464607.

Precision determination of electron scattering angle by differential nuclear recoil energy method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liyanage, N.; Saenboonruang, K.

2015-12-01

The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

Precision Determination of Electron Scattering Angle by Differential Nuclear Recoil Energy Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liyanage, Nilanga; Saenboonruang, Kiadtisak

2015-09-01

The accurate determination of the scattered electron angle is crucial to electron scattering experiments, both with open-geometry large-acceptance spectrometers and ones with dipole-type magnetic spectrometers for electron detection. In particular, for small central-angle experiments using dipole-type magnetic spectrometers, in which surveys are used to measure the spectrometer angle with respect to the primary electron beam, the importance of the scattering angle determination is emphasized. However, given the complexities of large experiments and spectrometers, the accuracy of such surveys is limited and insufficient to meet demands of some experiments. In this article, we present a new technique for determination of themore » electron scattering angle based on an accurate measurement of the primary beam energy and the principle of differential nuclear recoil. This technique was used to determine the scattering angle for several experiments carried out at the Experimental Hall A, Jefferson Lab. Results have shown that the new technique greatly improved the accuracy of the angle determination compared to surveys.« less

Glaucoma and clinical characteristics in Vietnamese Americans.

PubMed

Peng, Pai-Huei; Manivanh, Richard; Nguyen, Ngoc; Weinreb, Robert N; Lin, Shan C

2011-08-01

To assess the proportions of glaucoma types and clinical characteristics in Vietnamese Americans in a single-center, retrospective study. Medical charts of Vietnamese-American patients who visited a single private practice in Northern California from 1998-2007 were reviewed. The main outcome measures included the distribution and characteristics of glaucoma types, and clinical parameters associated with the presence of various glaucomas. Data from 2247 patients aged 18-98 years were reviewed. Glaucoma was determined for 305 patients (13.6%). Among this group, 54.8% had primary open-angle glaucoma (POAG), 26.9% had primary angle-closure glaucoma (PACG), 13.4% had mixed mechanism glaucoma (MMG), and 4.9% had secondary glaucoma. In the MMG group (41 patients), 27 patients who initially had open angles developed narrow angles and underwent laser peripheral iridotomy (LPI) with a mean follow up of 6.4 years from the time of iridotomy. The other 13 patients had glaucoma progression with open angles after LPI. One POAG patient had neovascular glaucoma due to retinal vein occlusion several years later. Compared to the PACG group, the MMG group had significantly lower baseline intraocular pressure (25.0 vs. 20.2 mmHg, p = 0.007) but with no difference in biometry. POAG is the major type of glaucoma in this clinic-based Vietnamese population. However, Vietnamese appear to have a relatively higher proportion of PACG than Caucasians and those of African descent. It is recommended that gonioscopy be part of the regular eye check-up for adult Vietnamese patients.

Brightness discrimination test is not useful in screening for open angle glaucoma.

PubMed

Peter, E; Thomas, R; Muliyil, J

1996-06-01

Brightness discrimination test (BDT) is routinely employed to assess asymmetrical optic nerve dysfunction and has been suggested as a screening test for primary open angle glaucoma (POAG). We tested the reliability and validity of BDT in the diagnosis of POAG. The study groups included 34 patients with established primary open angle glaucoma, 20 glaucoma suspects, and 33 age-sex matched controls. Cataract was not an exclusion criterion in these groups. The normal brightness score was determined to be 88% (mean score, 94%-2 SD) in a pilot study. Brightness discrimination test was performed in all subjects by two observers independently. BDT showed an excellent interobserver agreement (weighted Kappa 0.84). The presence of a cataract alone increased the risk of brightness impairment twofold, glaucoma alone increased the risk eightfold, and the presence of both conditions by 17 times compared to those with neither condition. BDT was not a useful test in the diagnosis of POAG (sensitivity 67% and specificity 93%); the ability to detect a significant field defect was also poor (sensitivity 53% and specificity 76%). There was poor association between decreased brightness scores and asymmetrical field defects as determined by the Humphrey's field analyzer (HFA).

Open-ocean fish reveal an omnidirectional solution to camouflage in polarized environments.

PubMed

Brady, Parrish C; Gilerson, Alexander A; Kattawar, George W; Sullivan, James M; Twardowski, Michael S; Dierssen, Heidi M; Gao, Meng; Travis, Kort; Etheredge, Robert Ian; Tonizzo, Alberto; Ibrahim, Amir; Carrizo, Carlos; Gu, Yalong; Russell, Brandon J; Mislinski, Kathryn; Zhao, Shulei; Cummings, Molly E

2015-11-20

Despite appearing featureless to our eyes, the open ocean is a highly variable environment for polarization-sensitive viewers. Dynamic visual backgrounds coupled with predator encounters from all possible directions make this habitat one of the most challenging for camouflage. We tested open-ocean crypsis in nature by collecting more than 1500 videopolarimetry measurements from live fish from distinct habitats under a variety of viewing conditions. Open-ocean fish species exhibited camouflage that was superior to that of both nearshore fish and mirrorlike surfaces, with significantly higher crypsis at angles associated with predator detection and pursuit. Histological measurements revealed that specific arrangements of reflective guanine platelets in the fish's skin produce angle-dependent polarization modifications for polarocrypsis in the open ocean, suggesting a mechanism for natural selection to shape reflectance properties in this complex environment. Copyright © 2015, American Association for the Advancement of Science.

Prospective, non-interventional, multicenter study of the intraocular pressure-lowering effects of prostaglandin analog/prostamide-containing therapies in previously treated patients with open-angle glaucoma or ocular hypertension

PubMed Central

Tamçelik, Nevbahar; Izgi, Belgin; Temel, Ahmet; Yildirim, Nilgun; Okka, Mehmet; Özcan, Altan; Yüksel, Nurşen; Elgin, Ufuk; Altan, Çiğdem; Ozer, Baris

2017-01-01

Objective The objective of this study was to assess the intraocular pressure (IOP)-lowering efficacy, tolerability, safety, and usage patterns of prostaglandin analog/prostamide (PGA/P)-containing topical ocular hypotensives in ocular hypertension (OHT) and primary open-angle glaucoma in the Turkish clinical setting. Methods This non-interventional, multicenter study enrolled previously treated patients who failed to achieve target IOP (or experienced unacceptable adverse events [AEs]) and were prescribed a PGA/P-containing IOP-lowering agent. Treatment was initiated at baseline (V1), and patients returned at weeks 4–6 (V2) and 8–12 (V3). The primary efficacy measure was the change in IOP from baseline at V3 in each eye. The secondary measures were physician’s assessment of IOP-lowering efficacy, patients (%) reaching target IOP determined at V1, hyperemia score, physician and patient assessment of study treatment tolerability at V3, and AE frequency/severity. A subgroup analysis of patients receiving the most common study treatment was conducted. All analyses were performed using the safety population (patients who received one or more doses and had any data available). Results Of 358 enrolled patients, 60.6% had primary open-angle glaucoma, 29.9% had secondary open-angle glaucoma (protocol amendment), and 13.1% had OHT; 13 patients had multiple diagnoses. At V3, the mean IOP change from baseline was ≥−4.2 mmHg (≥21.1%). IOP met or was lower than the target in 81.7% of patients, 95% exhibited none to mild conjunctival hyperemia (most common AE), and tolerability was rated good/very good by >91.1% of patients and physicians. The results were similar in patients who received the most common study treatment, bimatoprost 0.03%/timolol 0.5% (bim/tim; n=310). Conclusion PGA/P-containing medications, including bim/tim, significantly reduced IOP in previously treated patients with open-angle glaucoma or OHT; most reached their target IOP or an IOP even lower than their target and reported good/very good tolerability. PGA/P-containing medications such as bim/tim should be considered as a safe, effective therapeutic option for Turkish patients who exhibit poor response, tolerance, or adherence to their previous therapy. PMID:28458511

Mapping a gene for adult-onset primary open-angle glaucoma to chromosome 3q

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wirtz, M.K.; Samples, J.R.; Kramer, P.L.

1997-02-01

Glaucoma is the third-leading cause of blindness in the world, affecting >13.5 million people. Adult-on-set primary open-angle glaucoma (POAG) is the most common form of glaucoma in the United States. We present a family in which adult-onset POAG is inherited as an autosomal dominant trait. Twelve affected family members were identified from 44 at-risk individuals. The disease-causing gene was mapped to chromosome 3q21-24, with analysis of recombinant haplotypes suggesting a total inclusion region of 11.1 cM between markers D3S3637 and D3S1744. This is the first report of mapping of an adult-onset POAG gene to chromosome 3q, gene symbol GLC1C. 57more » refs., 3 figs., 3 tabs.« less

Comparison of optical coherence tomography findings and visual field changes in patients with primary open-angle glaucoma and amyotrophic lateral sclerosis.

PubMed

Liu, Ziyuan; Wang, Hongli; Fan, Dongsheng; Wang, Wei

2018-02-01

Recent studies revealing genetic connection of primary open angle glaucoma (POAG) and amyotrophic lateral sclerosis (ALS) have received particular attention. Exploring the evidence for common pathogenesis of these two progressive neurological disorders may assist in understanding the mechanism and searching for new treatment. Retinal nerve fiber layer (RNFL) defect and corresponding visual field (VF) impairment are well known neuropathy signs in glaucoma. In our study, thickness of certain retinal layer in ALS patients was analyzed to detect ganglion cell's soma and axon, and for first time visual field was examined for ALS. The correlation of retinal involvement and ALS progression were also investigated. The results were compared with those of POAG. The study may provide new knowledge for these two neurodegenerative diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effectiveness of early lens extraction with intraocular lens implantation for the treatment of primary angle-closure glaucoma (EAGLE): study protocol for a randomized controlled trial

PubMed Central

2011-01-01

Background Glaucoma is the leading cause of irreversible blindness. Although primary open-angle glaucoma is more common, primary angle-closure glaucoma (PACG) is more likely to result in irreversible blindness. By 2020, 5·3 million people worldwide will be blind because of PACG. The current standard care for PACG is a stepped approach of a combination of laser iridotomy surgery (to open the drainage angle) and medical treatment (to reduce intraocular pressure). If these treatments fail, glaucoma surgery (eg, trabeculectomy) is indicated. It has been proposed that, because the lens of the eye plays a major role in the mechanisms leading to PACG, early clear lens extraction will improve glaucoma control by opening the drainage angle. This procedure might reduce the need for drugs and glaucoma surgery, maintain good visual acuity, and improve quality of life compared with standard care. EAGLE aims to evaluate whether early lens extraction improves patient-reported, clinical outcomes, and cost-effectiveness, compared with standard care. Methods/Design EAGLE is a multicentre pragmatic randomized trial. All people presenting to the recruitment centres in the UK and east Asia with newly diagnosed PACG and who are at least 50 years old are eligible. The primary outcomes are EQ-5D, intraocular pressure, and incremental cost per quality adjusted life year (QALY) gained. Other outcomes are: vision and glaucoma-specific patient-reported outcomes, visual acuity, visual field, angle closure, number of medications, additional surgery (e.g., trabeculectomy), costs to the health services and patients, and adverse events. A single main analysis will be done at the end of the trial, after three years of follow-up. The analysis will be based on all participants as randomized (intention to treat). 400 participants (200 in each group) will be recruited, to have 90% power at 5% significance level to detect a difference in EQ-5D score between the two groups of 0·05, and a mean difference in intraocular pressure of 1·75 mm Hg. The study will have 80% power to detect a difference of 15% in the glaucoma surgery rate. Trial Registration: ISRCTN44464607. PMID:21605352

Steroid-induced glaucoma treated with trabecular ablation in a matched comparison with primary open-angle glaucoma.

PubMed

Dang, Yalong; Kaplowitz, Kevin; Parikh, Hardik A; Roy, Pritha; Loewen, Ralitsa T; Francis, Brian A; Loewen, Nils A

2016-12-01

To evaluate the outcomes of trabectome-mediated ab interno trabeculectomy in patients with steroid-induced glaucoma (SIG). A retrospective, observational cohort study performed in the Department of Ophthalmology, University of Pittsburgh Medical Center. The data of 60 patients with SIG and 484 controls with primary open-angle glaucoma (POAG) matched by age, gender and glaucoma index were collected from the Trabectome Study Group database. Reduction of intraocular pressure (IOP) and medications were compared between POAG and SIG by multivariate regression. Kaplan-Meier was used for survival analysis. Success was defined as IOP ≤21 mmHg and at least 20% IOP reduction from baseline for any two consecutive visits after 3 months without secondary glaucoma surgery. Postoperative IOP and number of medications were compared with baseline in the SIG subgroups by the Wilcoxon test. Intraocular pressure reduction and 1-year success rate. Patients with SIG had a higher baseline IOP (31.4 ± 10.4 vs. 24.1 ± 7.6 mmHg, P < 0.01) and obtained a greater IOP reduction than controls with POAG (48.4% vs. 31.5%, P < 0.01). Multivariate regression showed that patients with SIG had an IOP reduction of 6.7 ± 1.1 mmHg more than those with POAG. Survival rates at 12 months were comparable at 86% in the SIG group and 85% in the POAG group (P = 0.47). Patients with SIG with a high baseline IOP, younger age and advanced glaucoma experienced a larger IOP drop. Trabectome appears to be an effective surgical treatment in reducing IOP for patients with SIG. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

75 FR 69737 - Qualification of Drivers; Exemption Applications; Vision

Federal Register 2010, 2011, 2012, 2013, 2014

2010-11-15

... moving violations in a CMV. Michael E. Herrera, Jr., Mr. Herrera, 53, has had primary open angle glaucoma... opinion. Mr. Herrera has sufficient vision to drive a commercial vehicle. Mr. Herrera reported that he has...

Common variants near CAV1 and CAV2 are associated with primary open-angle glaucoma

PubMed Central

Thorleifsson, Gudmar; Walters, G Bragi; Hewitt, Alex W; Masson, Gisli; Helgason, Agnar; DeWan, Andrew; Sigurdsson, Asgeir; Jonasdottir, Adalbjorg; Gudjonsson, Sigurjon A; Magnusson, Kristinn P; Stefansson, Hreinn; Lam, Dennis S C; Tam, Pancy O S; Gudmundsdottir, Gudrun J; Southgate, Laura; Burdon, Kathryn P; Gottfredsdottir, Maria Soffia; Aldred, Micheala A; Mitchell, Paul; St Clair, David; Collier, David A; Tang, Nelson; Sveinsson, Orn; Macgregor, Stuart; Martin, Nicholas G; Cree, Angela J; Gibson, Jane; MacLeod, Alex; Jacob, Aby; Ennis, Sarah; Young, Terri L; Chan, Juliana C N; Karwatowski, Wojciech S S; Hammond, Christopher J; Thordarson, Kristjan; Zhang, Mingzhi; Wadelius, Claes; Lotery, Andrew J; Trembath, Richard C; Pang, Chi Pui; Hoh, Josephine; Craig, Jamie E; Kong, Augustine; Mackey, David A; Jonasson, Fridbert; Thorsteinsdottir, Unnur; Stefansson, Kari

2011-01-01

We conducted a genome-wide association study for primary open-angle glaucoma (POAG) in 1,263 affected individuals (cases) and 34,877 controls from Iceland. We identified a common sequence variant at 7q31 (rs4236601[A], odds ratio (OR) = 1.36, P = 5.0 × 10-10). We then replicated the association in sample sets of 2,175 POAG cases and 2,064 controls from Sweden, the UK and Australia (combined OR = 1.18, P = 0.0015) and in 299 POAG cases and 580 unaffected controls from Hong Kong and Shantou, China (combined OR = 5.42, P = 0.0021). The risk variant identified here is located close to CAV1 and CAV2, both of which are expressed in the trabecular meshwork and retinal ganglion cells that are involved in the pathogenesis of POAG. PMID:20835238

Structure-Function Correlations using Scanning Laser Polarimetry in Primary Angle-Closure Glaucoma and Primary Open Angle Glaucoma

PubMed Central

Lee, Pei-Jung; Liu, Catherine Jui-Ling.; Wojciechowski, Robert; Bailey-Wilson, Joan E.; Cheng, Ching-Yu

2010-01-01

Purpose To assess the correlations between retinal nerve fiber layer (RNFL) thickness measured with scanning laser polarimetry (SLP) and visual field (VF) sensitivity in primary open angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Design Prospective, comparative, observational cases series Methods Fifty patients with POAG and 56 with PACG were examined using SLP with variable corneal compensation (GDx VCC) and Humphrey VF analyzer between August 2005 and July 2006 at Taipei Veterans General Hospital. Correlations between RNFL thickness and VF sensitivity, expressed as mean sensitivity (MS) in both decibel (dB) and 1/Lambert (L) scales, were estimated by Spearman's rank correlation coefficient (rs) and multivariate median regression models (pseudo R2). The correlations were determined globally and for six RNFL sectors and their corresponding VF regions. Results The correlation between RNFL thickness and MS (in dB) was weaker in the PACG group (rs = 0.38, P = 0.004, pseudo R2 = 0.17) than in the POAG group (rs = 0.51, P <0.001, pseudo R2 = 0.31), but the difference in the magnitude of correlation was not significant (P = 0.42).With Bonferroni correction, the structure-function correlation was significant in the superotemporal (rs = 0.62), superonasal (rs = 0.56), inferonasal (rs = 0.53), and inferotemporal (rs = 0.50) sectors in the POAG group (all P <0.001), while it was significant only in the superotemporal (rs = 0.53) and inferotemporal (rs = 0.48) sectors in the PACG group (both P <0.001). The results were similar when MS was expressed as 1/L scale. Conclusions Both POAG and PACG eyes had moderate structure-function correlations using SLP. Compared to eyes with POAG, fewer RNFL sectors have significant structure-function correlations in eyes with PACG. PMID:20202618

Distinct iris gene expression profiles of primary angle closure glaucoma and primary open angle glaucoma and their interaction with ocular biometric parameters.

PubMed

Seet, Li-Fong; Narayanaswamy, Arun; Finger, Sharon N; Htoon, Hla M; Nongpiur, Monisha E; Toh, Li Zhen; Ho, Henrietta; Perera, Shamira A; Wong, Tina T

2016-11-01

This study aimed to evaluate differences in iris gene expression profiles between primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) and their interaction with biometric characteristics. Prospective study. Thirty-five subjects with PACG and thirty-three subjects with POAG who required trabeculectomy were enrolled at the Singapore National Eye Centre, Singapore. Iris specimens, obtained by iridectomy, were analysed by real-time polymerase chain reaction for expression of type I collagen, vascular endothelial growth factor (VEGF)-A, -B and -C, as well as VEGF receptors (VEGFRs) 1 and 2. Anterior segment optical coherence tomography (ASOCT) imaging for biometric parameters, including anterior chamber depth (ACD), anterior chamber volume (ACV) and lens vault (LV), was also performed pre-operatively. Relative mRNA levels between PACG and POAG irises, biometric measurements, discriminant analyses using genes and biometric parameters. COL1A1, VEGFB, VEGFC and VEGFR2 mRNA expression was higher in PACG compared to POAG irises. LV, ACD and ACV were significantly different between the two subgroups. Discriminant analyses based on gene expression, biometric parameters or a combination of both gene expression and biometrics (LV and ACV), correctly classified 94.1%, 85.3% and 94.1% of the original PACG and POAG cases, respectively. The discriminant function combining genes and biometrics demonstrated the highest accuracy in cross-validated classification of the two glaucoma subtypes. Distinct iris gene expression supports the pathophysiological differences that exist between PACG and POAG. Biometric parameters can combine with iris gene expression to more accurately define PACG from POAG. © 2016 The Authors. Clinical & Experimental Ophthalmology published by John Wiley & Sons Australia, Ltd on behalf of Royal Australian and New Zealand College of Ophthalmologists.

Impact of Socioeconomic Status on the Diagnosis of Primary Open-Angle Glaucoma and Primary Angle Closure Glaucoma: A Nationwide Population-Based Study in Taiwan.

PubMed

Ko, Yu-Chieh; Hwang, De-Kuang; Chen, Wei-Ta; Lee, Ching-Chih; Liu, Catherine J

2016-01-01

To understand the impact of socioeconomic status (SES) on the diagnosis of primary open-angle glaucoma (POAG) and primary angle closure glaucoma (PACG) in Taiwan. Subjects with glaucoma were identified from the National Health Insurance Research Database of year 2006, which included one million randomly selected insurants. Individuals who had ≥4 ambulatory visits within one year which had the diagnosis code of POAG (ICD-9-CM 365.11 or 365.12) or PACG (365.23) and concurrent prescription of anti-glaucoma medication or surgery were selected. Individual SES was represented by monthly income calculated from the insurance premium. Neighborhood SES was defined based on neighborhood household income averages. Urbanization level of habitation was categorized into 3 levels. The odds ratio of having POAG or PACG in subjects with different SES was evaluated by using multiple logistic regression analysis. In total, 752 and 561 subjects with POAG and PACG, respectively, who were treated on a regular basis, were identified. The diagnosis of glaucoma was affected by age, gender, frequency of healthcare utilization, individual SES, and urbanization level of habitation. With the adjustment of age, gender, healthcare utilization, neighborhood SES and level of urbanization, subjects with lower income were more likely to be diagnosed as PACG, but less likely as POAG. Subjects with more frequent healthcare utilization were more likely to be diagnosed with glaucoma. Subjects with low SES were more susceptible to PACG, but subjects with high SES were more likely to be diagnosed as POAG. This information is useful for the design and target participant setting in glaucoma education and screening campaign to maximize the efficacy of limited resources in preventing glaucoma blindness.

Open-angle glaucoma in the Petit Basset Griffon Vendeen.

PubMed

Bedford, Peter G C

2017-03-01

To report the prevalence and clinical characteristics of an open-angle glaucoma in Petit Basset Griffon Vendeen (PBGV) dogs in the United Kingdom (UK). At breed society clinics extending over a 6-year period, 366 dogs of varying ages and both sexes were clinically examined for signs of glaucoma using slit-lamp biomicroscopy, indirect and direct ophthalmoscopy, tonometry, and gonioscopy. The prevalence of glaucoma was 10.4% (38 dogs). Clinical signs of the disease presented from 3 years of age onwards, the commonest initial feature being the elevation of intraocular pressure (IOP) in 15 dogs (39.4%). In addition to elevated IOP, another 13 dogs (34.2%) presented with other features of glaucoma, some with lens subluxation and globe enlargement and all with possible or known vision defects. In the remaining 10 dogs (26.3%), phacodonesis or lens subluxation was observed before subsequent elevation of IOP. High prevalence and similarity to the primary open-angle glaucoma (POAG) seen in the Beagle and Elkhound breeds indicate that an open-angle glaucoma is present in the PBGV in the UK and that this disease may be genetically determined in this breed. Although increased IOP is the commonest early diagnostic feature, lens instability prior to an increase in IOP may be part of the clinical picture. © 2016 American College of Veterinary Ophthalmologists.

Long Term Results of Visual Field Progression Analysis in Open Angle Glaucoma Patients Under Treatment.

PubMed

Kocatürk, Tolga; Bekmez, Sinan; Katrancı, Merve; Çakmak, Harun; Dayanır, Volkan

2015-01-01

To evaluate visual field progression with trend and event analysis in open angle glaucoma patients under treatment. Fifteen year follow-up results of 408 eyes of 217 glaucoma patients who were followed at Adnan Menderes University, Department of Ophthalmology between 1998 and 2013 were analyzed retrospectively. Visual field data were collected for Mean Deviation (MD), Visual Field Index (VFI), and event occurrence. There were 146 primary open-angle glaucoma (POAG), 123 pseudoexfoliative glaucoma (XFG) and 139 normal tension glaucoma (NTG) eyes. MD showed significant change in all diagnostic groups (p<0.001). The difference of VFI between first and last examinations were significantly different in POAG (p<0.001), and XFG (p<0.003) but not in NTG. VFI progression rates were -0.3, -0.43, and -0.2 % loss/year in treated POAG, XFG, and NTG, respectively. The number of empty triangles were statistically different between POAG-NTG (p=0.001), and XFG-NTG (p=0.002) groups. The number of half-filled (p=0.002), and full-filled (p=0.010) triangles were significantly different between XFG-NTG groups. Functional long-term follow-up of glaucoma patients can be monitored with visual field indices. We herein report our fifteen year follow-up results in open angle glaucoma.

Linkage analysis excludes the glaucoma locus on 1q from involvement in autosomal dominant glaucoma with iris hypoplasia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heon, E.; Sheth, B.P.; Kalenak, J.W.

1994-09-01

Genetic factors have been implicated in a variety of types of glaucoma including primary open-angle glaucoma, infantile glaucoma, pigmentary glaucoma, and juvenile open-angle glaucoma. We previously mapped the disease-causing gene for one type of juvenile open angle glaucoma to chromosome 1q21-31. Weatherill and Hart (1969) and Pearce (1983) each noted the association of iris hypoplasia and early-onset autosomal dominant glaucoma. We recently had the opportunity to study a large family (12 affected members) with this phenotype. Affected individuals developed glaucoma at an average age of 30 years. These patients also have a strikingly underdeveloped iris stroma which causes a peculiarmore » eye color. Linkage analysis was able to completely exclude the 1q glaucoma locus from involvement in the disorder that affects this family. A complete clinical description of the family and linkage results at additional candidate loci will be presented.« less

Transcorneal Electrical Stimulation Therapy for Retinal Disease

ClinicalTrials.gov

2012-05-03

Retinitis Pigmentosa; Macula Off; Primary Open Angle Glaucoma; Hereditary Macular Degeneration; Treated Retina Detachment; Retinal Artery Occlusion; Retinal Vein Occlusion; Non-Arthritic-Anterior-Ischemic Optic-Neuropathy; Hereditary Autosomal Dominant Optic Atrophy; Dry Age Related Macular Degeneration; Ischemic Macula Edema

Trabeculotomy combined with phacoemulsification and implantation of an intraocular lens for the treatment of primary open-angle glaucoma and coexisting cataract.

PubMed

Tanihara, H; Honjo, M; Inatani, M; Honda, Y; Ogino, N; Ueno, S; Negi, A; Ichioka, H; Mizoguchi, T; Matsumura, M; Nagata, M

1997-10-01

The authors previously reported the usefulness of trabeculotomy ab externo for the treatment of primary open-angle glaucoma in adult patients. In an attempt to elucidate the long-term risk-to-benefit ratio of this surgical modality in combination with cataract surgery, the authors conducted a retrospective study of the surgical effects and complications of a triple procedure: phacoemulsification, implantation (of an intraocular lens), and trabeculotomy (PIT). The authors conducted a retrospective study of patients treated with PIT at multiple hospitals. Intraocular pressure (IOP) and visual function data were obtained from patients after PIT as an initial surgical treatment in cases where antiglaucoma medications failed to resolve uncontrolled IOP (higher than 21 mm Hg). Included in this study were 96 eyes of 64 patients with primary open-angle glaucoma and coexisting cataract. The mean follow-up period was 22.6 +/- 14.7 months (range 3-56 months). In 94 (98%) of the 96 eyes, the IOP was well controlled, having achieved a level of 21 mm Hg or lower at the final examinations. The mean preoperative IOP of the 33 eyes that underwent the triple procedure using a single flap method (PIT-I) was 24.3 +/- 3.9 mm Hg, with an average of 2.1 +/- 1.1 medications. At the final examinations, the mean IOP had dropped to 16.0 +/- 1.2 mm Hg, with an average of 1.2 +/- 1.2 medications. The mean preoperative IOP of the 63 eyes that underwent the triple procedure using a double flap method (PIT-II) was 26.2 +/- 6.2 mm Hg, with an average of 1.9 +/- 1.2 medications. At the final examination, the mean IOP for this group was 15.6 +/- 2.9 mm Hg, with an average of 1.0 +/- 0.9 medications. The long-term results from this multicenter study showed that the triple procedure, PIT, can be useful and effective as an initial surgical treatment for open-angle glaucoma in glaucoma patients with coexisting cataract.

Friction Angles of Open-Graded Aggregates from Large-Scale Direct Shear Testing : TechBrief

DOT National Transportation Integrated Search

2013-07-08

State and local transportation agencies frequently use opengraded aggregates for wall, roadway, and bridge construction. The primary advantages of using this type of material in wall and abutment applications are ease of constructability, lighter in-...

[Perimetric changes in advanced glaucoma].

PubMed

Feraru, Crenguta Ioana; Pantalon, Anca

2011-01-01

The evaluation of various perimetric aspects in advanced glaucoma stages correlated to morpho-functional changes. MATHERIAL AND METHOD: Retrospective clinical trial over a 10 months time period that included patients with advanced glaucoma stages, for which there have been recorded several computerised visual field tests (central 24-2 strategy, 10-2 strategy with either III or V--Goldman stimulus spot size) along with other morpho-funtional ocular paramaters: VA, lOP optic disk analysis. We included in our study 56 eyes from 45 patients. In most cases 89% it was an open angle glaucoma (either primary or secondary) Mean visual acuity was 0.45 +/- 0.28. Regarding the perimetric deficit 83% had advanced deficit, 9% moderate and 8% early visual changes. As perimetric type of defect we found a majority with general reduction of sensitivity (33 eyes) + ring shape scotoma. In 6 eyes (10.7%) having left only a central isle of vision we performed the central 10-2 strategy with III or V Goldmann stimulus spot size. Statistic analysis showed scarce correlation between the visual acuity and the quantitative perimetric parameters (MD and PSD), and variance analysis found present a multiple correlation parameter p = 0.07 that proves there is no liniary correspondence between the morpho-functional parameters: VA-MD(PSD) and C/D ratio. In advanced glaucoma stages, the perimetric changes are mostly severe. Perimetric evaluation is essential in these stages and needs to be individualised.

Open-field arena boundary is a primary object of exploration for Drosophila

PubMed Central

Soibam, Benjamin; Mann, Monica; Liu, Lingzhi; Tran, Jessica; Lobaina, Milena; Kang, Yuan Yuan; Gunaratne, Gemunu H; Pletcher, Scott; Roman, Gregg

2012-01-01

Drosophila adults, when placed into a novel open-field arena, initially exhibit an elevated level of activity followed by a reduced stable level of spontaneous activity and spend a majority of time near the arena edge, executing motions along the walls. In order to determine the environmental features that are responsible for the initial high activity and wall-following behavior exhibited during exploration, we examined wild-type and visually impaired mutants in arenas with different vertical surfaces. These experiments support the conclusion that the wall-following behavior of Drosophila is best characterized by a preference for the arena boundary, and not thigmotaxis or centrophobicity. In circular arenas, Drosophila mostly move in trajectories with low turn angles. Since the boundary preference could derive from highly linear trajectories, we further developed a simulation program to model the effects of turn angle on the boundary preference. In an hourglass-shaped arena with convex-angled walls that forced a straight versus wall-following choice, the simulation with constrained turn angles predicted general movement across a central gap, whereas Drosophila tend to follow the wall. Hence, low turn angled movement does not drive the boundary preference. Lastly, visually impaired Drosophila demonstrate a defect in attenuation of the elevated initial activity. Interestingly, the visually impaired w1118 activity decay defect can be rescued by increasing the contrast of the arena's edge, suggesting that the activity decay relies on visual detection of the boundary. The arena boundary is, therefore, a primary object of exploration for Drosophila. PMID:22574279

The effect of internal fixation lamp on anterior chamber angle width measured by anterior segment optical coherence tomography.

PubMed

Nakamine, Sakari; Sakai, Hiroshi; Arakaki, Yoshikuni; Yonahara, Michiko; Kaiya, Tadayoshi

2018-01-01

To study the effect of the internal fixation lamp on anterior chamber width measured by anterior segment optical coherence tomography. In a prospective cross sectional observational study, consecutive 22 right eyes of 22 patients (4 men and 18 women) with suspected primary angle closure underwent swept source domain anterior segment optical coherence tomography (AS-OCT), (CASIA SS-1000, Tomey, Nagoya, Japan). Anterior chamber parameters of angle opening distance (AOD), trabecular-iris angle (TIA), angle recess area (ARA) at 500 or 750 µm from scleral spur and pupil diameter were measured by AS-OCT in a three-dimensional mode in 4 quadrants (superior, inferior, temporal and nasal) in dark room setting both with and without internal fixation lamp. Anterior segment parameters of AOD 500 in superior, inferior and temporal quadrants, AOD 750 at superior and nasal, TIA 500 at superior, and inferior and TIA 750 at superior and nasal, and ARA 500 or 750 at superior and inferior with internal fixation lamp were greater and the pupil diameter was significantly (all P < 0.05, paired t test) smaller than when measured without fixation lamp. Internal fixation lamp of the anterior segment OCT makes the pupil constrict and angle wider. When using AS-OCT with usual setting with internal fixation lamp on with eyes in which the anterior chamber angle is narrow but open, it is recommended that the internal fixation lamp be turned off to ensure a clear indication as to whether the angle is open or closed in the dark.

C677T polymorphism in the methylenetetrahydrofolate reductase gene is associated with primary closed angle glaucoma

PubMed Central

Michael, Shazia; Qamar, Raheel; Akhtar, Farah; Khan, Wajid Ali

2008-01-01

Purpose To determine whether or not there is an association of the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism with disease in cohorts of primary open-angle glaucoma (POAG) and primary closed-angle glaucoma (PCAG) from Pakistan. Methods This was a prospective study consisting of 150 patients (90 POAG and 60 PCAG) and 70 control subjects. Genomic DNA was extracted from leukocytes of the peripheral blood. MTHFR C677T polymorphism analysis was performed by the polymerase chain reaction-restriction fragment length polymorphism (RFLP) technique. Results The prevalence of the MTHFR C/T genotype was 22.2% in POAG, 13.3% in PACG, and 18.6% in controls whereas the MTHFR T/T genotype was present solely in the PACG group (6.9%). The difference regarding the T/T genotype between PACG and controls was statistically significant (p<0.01). Conclusions The MTHFR C677T polymorphism was found to be associated with PCAG but not POAG in patients of Pakistani origin. PMID:18385801

Colliding Stellar Winds Structure and X-ray Emission

NASA Astrophysics Data System (ADS)

Pittard, J. M.; Dawson, B.

2018-04-01

We investigate the structure and X-ray emission from the colliding stellar winds in massive star binaries. We find that the opening angle of the contact discontinuity (CD) is overestimated by several formulae in the literature at very small values of the wind momentum ratio, η. We find also that the shocks in the primary (dominant) and secondary winds flare by ≈20° compared to the CD, and that the entire secondary wind is shocked when η ≲ 0.02. Analytical expressions for the opening angles of the shocks, and the fraction of each wind that is shocked, are provided. We find that the X-ray luminosity Lx∝η, and that the spectrum softens slightly as η decreases.

Localization of a locus (GLC1B) for adult-onset primary open angle glaucoma to the 2cen-q13 region

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoilova, D.; Trifan, O.C.; Sarfarazi, M.

1996-08-15

Primary open angle glaucoma (GLC1) is a common ocular disorder with a characteristic degeneration of the optic nerve and visual field defects that is often associated with an elevated intraocular pressure. The severe but rare juvenile-onset type has previously been mapped to 1q21-q31, and its genetic heterogeneity has been established. Herein, we present a new locus (GLC1B) for one form of GLC1 on chromosome 2cen-q13 with a clinical presentation of low to moderate intraocular pressure, onset in late 40s, and a good response to medical treatment. Two-point and haplotype analyses of affected and unaffected meioses in six families provided maximummore » linkage information with D2S417, GATA112EO3, D2S113, D2S373, and D2S274 (lod scores ranging from 3.11 to 6.48) within a region of 8.5 cM that is flanked by D2S2161 and D2S2264. Analysis of affected meioses alone revealed no recombination with an additional two markers (D2S2264 and D2S135) in a region of 11.2 cM that is flanked by D2S2161 and D2S176. Analysis of unaffected meioses identified only one healthy 86-year-old male who has inherited the entire affected haplotype and, hence, is a gene carrier for this condition. Eight additional families with similar and/or different clinical presentation did not show any linkage to this region and, therefore, provided evidence for genetic heterogeneity of adult-onset primary open angle glaucoma. 63 refs., 2 figs., 2 tabs.« less

Risk Factors Associated with Progression to Blindness from Primary Open-Angle Glaucoma in an African-American Population.

PubMed

Pleet, Alexander; Sulewski, Melanie; Salowe, Rebecca J; Fertig, Raymond; Salinas, Julia; Rhodes, Allison; Merritt Iii, William; Natesh, Vikas; Huang, Jiayan; Gudiseva, Harini V; Collins, David W; Chavali, Venkata Ramana Murthy; Tapino, Paul; Lehman, Amanda; Regina-Gigiliotti, Meredith; Miller-Ellis, Eydie; Sankar, Prithvi; Ying, Gui-Shuang; O'Brien, Joan M

2016-08-01

To determine the risk factors associated with progression to blindness from primary open-angle glaucoma (POAG) in an African-American population. This study examined 2119 patients enrolled in the Primary Open-Angle African-American Glaucoma Genetics (POAAGG) study. A total of 59 eyes were identified as legally blind as a result of POAG (cases) and were age-and sex-matched to 59 non-blind eyes with glaucoma (controls). Chart reviews were performed to record known and suspected risk factors. Cases were diagnosed with POAG at an earlier age than controls (p = 0.005). Of the 59 eyes of cases, 16 eyes (27.1%) presented with blindness at diagnosis. Cases had worse visual acuity (VA) at diagnosis (p < 0.0001), with VA worse than 20/40 conferring a 27 times higher risk of progression to blindness (p = 0.0005). Blind eyes also demonstrated more visual field defects (p = 0.01), higher pre-treatment intraocular pressure (IOP; p < 0.0001), and higher cup-to-disc ratio (p = 0.006) at diagnosis. IOP was less controlled in cases, and those with IOP ≥21 mmHg at more than 20% of follow-up visits were 73 times more likely to become blind (p < 0.0001). Cases missed a greater number of appointments per year (p = 0.003) and had non-adherence issues noted in their charts more often than controls (p = 0.03). However, other compliance data did not significantly differ between groups. Access to care, initial VA worse than 20/40, and poor control of IOP were the major risk factors associated with blindness from POAG. Future studies should examine earlier, more effective approaches to glaucoma screening as well as the role of genetics in these significantly younger patients who progress to blindness.

The association between clinical parameters and glaucoma-specific quality of life in Chinese primary open-angle glaucoma patients.

PubMed

Lee, Jacky W Y; Chan, Catherine W S; Chan, Jonathan C H; Li, Q; Lai, Jimmy S M

2014-08-01

OBJECTIVE. To investigate the association between clinical measurements and glaucoma-specific quality of life in Chinese glaucoma patients. DESIGN. Cross-sectional study. SETTING. An academic hospital in Hong Kong. PATIENTS. A Chinese translation of the Glaucoma Quality of Life-15 questionnaire was completed by 51 consecutive patients with bilateral primary open-angle glaucoma. The binocular means of several clinical measurements were correlated with Glaucoma Quality of Life-15 findings using Pearson's correlation coefficient and linear regression. The measurements were the visual field index and pattern standard deviation from the Humphrey Field Analyzer, Snellen best-corrected visual acuity, presenting intra-ocular pressure, current intra-ocular pressure, average retinal nerve fibre layer thickness via optical coherence tomography, and the number of topical anti-glaucoma medications being used. RESULTS. In these patients, there was a significant correlation and linear relationship between a poorer Glaucoma Quality of Life-15 score and a lower visual field index (r=0.3, r(2)=0.1, P=0.01) and visual acuity (r=0.3, r(2)=0.1, P=0.03). A thinner retinal nerve fibre layer also correlated with a poorer Glaucoma Quality of Life-15 score, but did not attain statistical significance (r=0.3, P=0.07). There were no statistically significant correlations for the other clinical parameters with the Glaucoma Quality of Life-15 scores (all P values being >0.7). The three most problematic activities affecting quality of life were "adjusting to bright lights", "going from a light to a dark room or vice versa", and "seeing at night". CONCLUSION. For Chinese primary open-angle glaucoma patients, binocular visual field index and visual acuity correlated linearly with glaucoma-specific quality of life, and activities involving dark adaptation were the most problematic.

Mutation analysis of seven known glaucoma-associated genes in Chinese patients with glaucoma.

PubMed

Huang, Xiaobo; Li, Miaoling; Guo, Xiangming; Li, Shiqiang; Xiao, Xueshan; Jia, Xiaoyun; Liu, Xing; Zhang, Qingjiong

2014-05-13

To evaluate mutations in the MYOC, WDR36, OPTN, OPA1, NTF4, CYP1B1, and LTBP2 genes in a cohort of Chinese patients with primary glaucoma. Genomic DNA was prepared from 683 unrelated patients, including 50 with primary congenital glaucoma, 104 with juvenile open-angle glaucoma (JOAG), 186 with primary open-angle glaucoma (POAG), and 343 with primary angle-closure glaucoma (PACG). Mutations in the seven genes in 257 patients (36 with JOAG, 89 with POAG, and 132 with PACG) were initially analyzed by exome sequencing and then confirmed by Sanger sequencing. In addition, Sanger sequencing was used to detect MYOC mutations in the remaining 426 patients. Exome sequencing identified 19 mutations (6 in MYOC, 9 in WDR36, 3 in OPA1, and 1 in OPTN) in 20 of 257 patients, including 4 patients with JOAG, 8 patients with POAG, and 8 patients with PACG. No mutation was detected in the other three genes. In addition, Sanger sequencing detected additional MYOC mutations in 5 of the remaining 426 patients, including 3 patients with JOAG and 2 patients with POAG. Twenty-two mutations in MYOC, WDR36, OPA1, and OPTN were detected in 25 of the 683 patients with primary glaucoma, including nine MYOC mutations in 11 patients, nine WDR36 mutations in 11 patients, three OPA1 mutations in 3 patients, and one OPTN mutation in a patient who also carried a MYOC mutation. Eight mutations in MYOC, WDR36, and OPA1 in 8 of the 343 PACG patients are of uncertain significance and need to be analyzed further. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

[Dry eye syndrome in patients with primary open-angle glaucoma].

PubMed

Boyko, E V; Simakova, I L; Yakushev, D Yu; Ignat'ev, S A; Alekseev, I B; Mel'nikova, N V; Alyab'ev, M V; Mal'tsev, D S

2015-01-01

to determine the frequency and severity of dry eye syndrome (DES) in primary open-angle glaucoma (POAG) patients that are newly diagnosed or already receiving beta blocker instillation therapy. A total of 127 patients (190 eyes) with POAG were divided into two groups. Group 1 included 55 newly diagnosed patients (88 eyes), group 2-72 POAG patients (102 eyes) instilling timolol 0.5% twice daily into the affected eye. The control group included 20 patients (40 eyes) aged 60-88 years (73.6 ± 9.2 years on average) with early age-related cataract. DES was found in 69 POAG patients (79%) who was just starting their topical hypotensive therapy and 85 of those (84%) under treatment (p = 0.39). One should take into account when prescribing ocular hypotensive therapy that newly diagnosed POAG patients usually already suffer from a dry eye. The use of topical beta blockers that contain preservatives exacerbates dry eye signs and symptoms in these patients.

A common variant near TGFBR3 is associated with primary open angle glaucoma.

PubMed

Li, Zheng; Allingham, R Rand; Nakano, Masakazu; Jia, Liyun; Chen, Yuhong; Ikeda, Yoko; Mani, Baskaran; Chen, Li-Jia; Kee, Changwon; Garway-Heath, David F; Sripriya, Sarangapani; Fuse, Nobuo; Abu-Amero, Khaled K; Huang, Chukai; Namburi, Prasanthi; Burdon, Kathryn; Perera, Shamira A; Gharahkhani, Puya; Lin, Ying; Ueno, Morio; Ozaki, Mineo; Mizoguchi, Takanori; Krishnadas, Subbiah Ramasamy; Osman, Essam A; Lee, Mei Chin; Chan, Anita S Y; Tajudin, Liza-Sharmini A; Do, Tan; Goncalves, Aurelien; Reynier, Pascal; Zhang, Hong; Bourne, Rupert; Goh, David; Broadway, David; Husain, Rahat; Negi, Anil K; Su, Daniel H; Ho, Ching-Lin; Blanco, Augusto Azuara; Leung, Christopher K S; Wong, Tina T; Yakub, Azhany; Liu, Yutao; Nongpiur, Monisha E; Han, Jong Chul; Hon, Do Nhu; Shantha, Balekudaru; Zhao, Bowen; Sang, Jinghong; Zhang, NiHong; Sato, Ryuichi; Yoshii, Kengo; Panda-Jonas, Songhomita; Ashley Koch, Allison E; Herndon, Leon W; Moroi, Sayoko E; Challa, Pratap; Foo, Jia Nee; Bei, Jin-Xin; Zeng, Yi-Xin; Simmons, Cameron P; Bich Chau, Tran Nguyen; Sharmila, Philomenadin Ferdinamarie; Chew, Merwyn; Lim, Blanche; Tam, Pansy O S; Chua, Elaine; Ng, Xiao Yu; Yong, Victor H K; Chong, Yaan Fun; Meah, Wee Yang; Vijayan, Saravanan; Seongsoo, Sohn; Xu, Wang; Teo, Yik Ying; Cooke Bailey, Jessica N; Kang, Jae H; Haines, Jonathan L; Cheng, Ching Yu; Saw, Seang-Mei; Tai, E-Shyong; Richards, Julia E; Ritch, Robert; Gaasterland, Douglas E; Pasquale, Louis R; Liu, Jianjun; Jonas, Jost B; Milea, Dan; George, Ronnie; Al-Obeidan, Saleh A; Mori, Kazuhiko; Macgregor, Stuart; Hewitt, Alex W; Girkin, Christopher A; Zhang, Mingzhi; Sundaresan, Periasamy; Vijaya, Lingam; Mackey, David A; Wong, Tien Yin; Craig, Jamie E; Sun, Xinghuai; Kinoshita, Shigeru; Wiggs, Janey L; Khor, Chiea-Chuen; Yang, Zhenglin; Pang, Chi Pui; Wang, Ningli; Hauser, Michael A; Tashiro, Kei; Aung, Tin; Vithana, Eranga N

2015-07-01

Primary open angle glaucoma (POAG), a major cause of blindness worldwide, is a complex disease with a significant genetic contribution. We performed Exome Array (Illumina) analysis on 3504 POAG cases and 9746 controls with replication of the most significant findings in 9173 POAG cases and 26 780 controls across 18 collections of Asian, African and European descent. Apart from confirming strong evidence of association at CDKN2B-AS1 (rs2157719 [G], odds ratio [OR] = 0.71, P = 2.81 × 10(-33)), we observed one SNP showing significant association to POAG (CDC7-TGFBR3 rs1192415, ORG-allele = 1.13, Pmeta = 1.60 × 10(-8)). This particular SNP has previously been shown to be strongly associated with optic disc area and vertical cup-to-disc ratio, which are regarded as glaucoma-related quantitative traits. Our study now extends this by directly implicating it in POAG disease pathogenesis. © The Author 2015. Published by Oxford University Press.

A common variant near TGFBR3 is associated with primary open angle glaucoma

PubMed Central

Li, Zheng; Allingham, R. Rand; Nakano, Masakazu; Jia, Liyun; Chen, Yuhong; Ikeda, Yoko; Mani, Baskaran; Chen, Li-Jia; Kee, Changwon; Garway-Heath, David F.; Sripriya, Sarangapani; Fuse, Nobuo; Abu-Amero, Khaled K.; Huang, Chukai; Namburi, Prasanthi; Burdon, Kathryn; Perera, Shamira A.; Gharahkhani, Puya; Lin, Ying; Ueno, Morio; Ozaki, Mineo; Mizoguchi, Takanori; Krishnadas, Subbiah Ramasamy; Osman, Essam A.; Lee, Mei Chin; Chan, Anita S.Y.; Tajudin, Liza-Sharmini A.; Do, Tan; Goncalves, Aurelien; Reynier, Pascal; Zhang, Hong; Bourne, Rupert; Goh, David; Broadway, David; Husain, Rahat; Negi, Anil K.; Su, Daniel H; Ho, Ching-Lin; Blanco, Augusto Azuara; Leung, Christopher K.S.; Wong, Tina T.; Yakub, Azhany; Liu, Yutao; Nongpiur, Monisha E.; Han, Jong Chul; Hon, Do Nhu; Shantha, Balekudaru; Zhao, Bowen; Sang, Jinghong; Zhang, NiHong; Sato, Ryuichi; Yoshii, Kengo; Panda-Jonas, Songhomita; Ashley Koch, Allison E.; Herndon, Leon W.; Moroi, Sayoko E.; Challa, Pratap; Foo, Jia Nee; Bei, Jin-Xin; Zeng, Yi-Xin; Simmons, Cameron P.; Bich Chau, Tran Nguyen; Sharmila, Philomenadin Ferdinamarie; Chew, Merwyn; Lim, Blanche; Tam, Pansy O.S.; Chua, Elaine; Ng, Xiao Yu; Yong, Victor H.K.; Chong, Yaan Fun; Meah, Wee Yang; Vijayan, Saravanan; Seongsoo, Sohn; Xu, Wang; Teo, Yik Ying; Cooke Bailey, Jessica N.; Kang, Jae H.; Haines, Jonathan L.; Cheng, Ching Yu; Saw, Seang-Mei; Tai, E-Shyong; Richards, Julia E.; Ritch, Robert; Gaasterland, Douglas E.; Pasquale, Louis R.; Liu, Jianjun; Jonas, Jost B.; Milea, Dan; George, Ronnie; Al-Obeidan, Saleh A.; Mori, Kazuhiko; Macgregor, Stuart; Hewitt, Alex W.; Girkin, Christopher A.; Zhang, Mingzhi; Sundaresan, Periasamy; Vijaya, Lingam; Mackey, David A.; Wong, Tien Yin; Craig, Jamie E.; Sun, Xinghuai; Kinoshita, Shigeru; Wiggs, Janey L.; Khor, Chiea-Chuen; Yang, Zhenglin; Pang, Chi Pui; Wang, Ningli; Hauser, Michael A.; Tashiro, Kei; Aung, Tin; Vithana, Eranga N.

2015-01-01

Primary open angle glaucoma (POAG), a major cause of blindness worldwide, is a complex disease with a significant genetic contribution. We performed Exome Array (Illumina) analysis on 3504 POAG cases and 9746 controls with replication of the most significant findings in 9173 POAG cases and 26 780 controls across 18 collections of Asian, African and European descent. Apart from confirming strong evidence of association at CDKN2B-AS1 (rs2157719 [G], odds ratio [OR] = 0.71, P = 2.81 × 10−33), we observed one SNP showing significant association to POAG (CDC7–TGFBR3 rs1192415, ORG-allele = 1.13, Pmeta = 1.60 × 10−8). This particular SNP has previously been shown to be strongly associated with optic disc area and vertical cup-to-disc ratio, which are regarded as glaucoma-related quantitative traits. Our study now extends this by directly implicating it in POAG disease pathogenesis. PMID:25861811

Morning glory syndrome associated with primary open angle glaucoma--case report.

PubMed

Bozić, Marija; Hentova-Senćanić, Paraskeva; Marković, Vujica; Marjanović, Ivan

2014-01-01

Morning glory syndrome (MGS) is a rare congenital optic disc anomaly, first reported in 1970. MGS is a nonprogressive and untreatable condition, which usually occurs as an isolated ocular anomaly, and can be associated with the increased incidence of nonrhegmatogenous retinal detachment, and also with strabismus, afferent pupillary defect, visual field defects, presence of hyaloids artery remnants, ciliary body cyst, congenital cataract, lid hemangioma and preretinal gliosis. We report a clinical case of MGS associated with primary open angle glaucoma. The use of sophisticated diagnostic tools, such as retinal tomography and visual field testing is limited if multiple eye conditions are present, since optic disc does not have "usual" appearance that can be analyzed according to standard statistical databases. In treating and follow up of glaucoma cases associated with other diseases and conditions that affect the appearance and function of the optic nerve head, sometimes the use of modern technological methods is limited due to difficult interpretation of the obtained results.

The ‘structure-function’ relationship in glaucoma – past thinking and current concepts

PubMed Central

Malik, Rizwan; Swanson, William H.; Garway-Heath, David F

2013-01-01

An understanding of the relationship between functional and structural measures in primary open angle glaucoma (POAG) is necessary for both grading the severity of disease and for understanding the natural history of the condition. This article outlines the current evidence for the nature of this relationship, and highlights the current mathematical models linking structure and function. Large clinical trials demonstrate that both structural and functional change are apparent in advanced stages of disease, while, at an individual level, detectable structural abnormality may precede functional abnormality in some patients whilst the converse in true in other patients. Although the exact nature of the ‘structure-function’ relationship in POAG is still the topic of scientific debate and the subject of continuing research, this article aims to provide the clinician with an understanding of the past concepts and contemporary thinking in relation to the structure-function relationship in POAG. PMID:22339936

The spectrum of glaucoma presentation at Menelik II Hospital, Addis Ababa.

PubMed

Giorgis, Abeba T; Mulugeta, Abiye; Aga, Assegid; Deyassa, Neggusie

2012-07-01

Glaucoma is a major cause of blindness in Africa. However, many do not know if they have the disease until late. The aim of this study was to describe the type and severity of glaucoma at presentation A hospital based prospective review of 602 glaucoma patients was conducted over 18 month period ending in 2009. A special registry captured Socio demographic and clinical data at the glaucoma clinic of Menelik II Hospital in Addis Ababa. The vertical cup disc ratio (CDR) of the optic nerve head provided the bases to stage, the severity of glaucoma. Large portion of the total reviewed patients were men, 401 (66.6%) or above the age of 40 years, 484 (80.4%). The mean intraocular pressure was 28.5 and 30.6 in the right and left eye in mmHg. The leading subtypes of glaucoma, accounting 64.3% (n = 387), were Primary Open Angle Glaucoma, 227 (37.7%) and Pseudo exfoliation glaucoma, 160 (26.6%). At presentation, 260 (44%) and 109 (18%)) were unilaterally and bilaterally blind (vision < 3/60) respectively. Bilateral glaucoma was found in 464 (77%) and 366 (61%) presented with advanced stage (CDR > or = 9.0). Cases with advanced stage were likely to present with blindness [Odds Ratio (OR) -6.2 95% CI (3-8-10.1) and 6.9 95% CI (4.2-11.3)] or high Intraocular pressure >30mmHg [OR=3.4, 95% CI (2.2 -5.2) and 2.8, 95% CI (1.4-3.4)] in the respective right and left eyes. The stage, had no statistically significant association with age, sex, residence or type of glaucoma (Chi2 test, p > 0.05). A large proportion of patients still arrive at glaucoma clinic with a very late stage of open angle glaucoma. Intervention strategies are requiredfor early detection and treatment of glaucoma in Ethiopia.

Bilateral phacomorphic angle-closure glaucoma in a highly myopic patient secondary to isolated spherophakia.

PubMed

Sowka, Joseph; Girgis, Nadine

2010-09-01

Angle closure most commonly occurs in older hyperopic patients as a result of primary relative pupil block. Less frequently, angle closure occurs in highly myopic patients with conditions other than primary relative pupil block. This report presents the diagnosis, pathophysiologic mechanism, and management of a patient with both high myopia and bilateral advanced phacomorphic angle-closure glaucoma caused by isolated spherophakia. A 40-year-old asymptomatic man with very high myopic astigmatism presented with chronic angle closure and an intraocular pressure of 42 mmHg in both eyes. Additionally there was a nonmyopic fundus and 24-mm axial length, with a clear crystalline lens protruding through the pupillary plane in each eye, confirmed by B-scan ultrasonography. Gonioscopy and A-scan and B-scan ultrasonography identified the pathogenesis of intraocular pressure elevation, angle closure, and high myopia to be lenticular in origin. Initial medical therapy and subsequent laser iridotomy relieved the pupil block angle closure and successfully lowered intraocular pressure. Angle closure can occur in highly myopic eyes. Careful gonioscopy and ultrasonography can lead to the correct diagnosis and tailored management for these eyes. Phacomorphic angle-closure glaucoma from spherophakia is associated with Weill-Marchesani syndrome as well as a few other uncommon syndromes. Isolated pseudophakia is a rarely reported cause of phacomorphic angle closure. Copyright 2010 American Optometric Association. Published by Elsevier Inc. All rights reserved.

On the 'flip-flop' instability of Bondi-Hoyle accretion flows

NASA Technical Reports Server (NTRS)

Livio, Mario; Soker, Noam; Matsuda, Takuya; Anzer, Ulrich

1991-01-01

A simple physical interpretation is advanced by means of an analysis of the shock cone in the accretion flows past a compact object and with an examination of the accretion-line stability analyses. The stability of the conical shock is examined against small angular deflections with attention given to several simplifying assumptions. A line instability is identified in the Bondi-Hoyle accretion flows that leads to the formation of a large opening-angle shock. When the opening angle becomes large the instability becomes irregular oscillation. The analytical methodology is compared to previous numerical configurations that demonstrate different shock morphologies. The Bondi-Hoyle accretion onto a compact object is concluded to generate a range of nonlinear instabilities in both homogeneous and inhomogeneous cases with a quasiperiodic oscillation in the linear regime.

Structure-function correlations using scanning laser polarimetry in primary angle-closure glaucoma and primary open-angle glaucoma.

PubMed

Lee, Pei-Jung; Liu, Catherine Jui-Ling; Wojciechowski, Robert; Bailey-Wilson, Joan E; Cheng, Ching-Yu

2010-05-01

To assess the correlations between retinal nerve fiber layer (RNFL) thickness measured with scanning laser polarimetry and visual field (VF) sensitivity in primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG). Prospective, comparative, observational cases series. Fifty patients with POAG and 56 patients with PACG were examined using scanning laser polarimetry with variable corneal compensation (GDx VCC; Laser Diagnostic Technologies, Inc.) and Humphrey VF analyzer (Carl Zeiss Meditec, Inc.) between August 2005 and July 2006 at Taipei Veterans General Hospital. Correlations between RNFL thickness and VF sensitivity, expressed as mean sensitivity in both decibel and 1/Lambert scales, were estimated by the Spearman rank correlation coefficient (r(s)) and multivariate median regression models (pseudo R(2)). The correlations were determined globally and for 6 RNFL sectors and their corresponding VF regions. The correlation between RNFL thickness and mean sensitivity (in decibels) was weaker in the PACG group (r(s) = 0.38; P = .004; pseudo R(2) = 0.17) than in the POAG group (r(s) = 0.51; P < .001; pseudo R(2) = .31), but the difference in the magnitude of correlation was not significant (P = .42). With Bonferroni correction, the structure-function correlation was significant in the superotemporal (r(s) = 0.62), superonasal (r(s) = 0.56), inferonasal (r(s) = 0.53), and inferotemporal (r(s) = 0.50) sectors in the POAG group (all P < .001), whereas it was significant only in the superotemporal (r(s) = 0.53) and inferotemporal (r(s) = 0.48) sectors in the PACG group (both P < .001). The results were similar when mean sensitivity was expressed as 1/Lambert scale. Both POAG and PACG eyes had moderate structure-function correlations using scanning laser polarimetry. Compared with eyes with POAG, fewer RNFL sectors have significant structure-function correlations in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

Angle imaging: Advances and challenges

PubMed Central

Quek, Desmond T L; Nongpiur, Monisha E; Perera, Shamira A; Aung, Tin

2011-01-01

Primary angle closure glaucoma (PACG) is a major form of glaucoma in large populous countries in East and South Asia. The high visual morbidity from PACG is related to the destructive nature of the asymptomatic form of the disease. Early detection of anatomically narrow angles is important and the subsequent prevention of visual loss from PACG depends on an accurate assessment of the anterior chamber angle (ACA). This review paper discusses the advantages and limitations of newer ACA imaging technologies, namely ultrasound biomicroscopy, Scheimpflug photography, anterior segment optical coherence tomography and EyeCam, highlighting the current clinical evidence comparing these devices with each other and with clinical dynamic indentation gonioscopy, the current reference standard. PMID:21150037

Demonstration of angle widening using EyeCam after laser peripheral iridotomy in eyes with angle closure.

PubMed

Perera, Shamira A; Quek, Desmond T; Baskaran, Mani; Tun, Tin A; Kumar, Rajesh S; Friedman, David S; Aung, Tin

2010-06-01

To evaluate EyeCam in detecting changes in angle configuration after laser peripheral iridotomy (LPI) in comparison to gonioscopy, the reference standard. Prospective comparative study. Twenty-four subjects (24 eyes) with primary angle-closure glaucoma (PACG) were recruited. Gonioscopy and EyeCam (Clarity Medical Systems) imaging of all 4 angle quadrants were performed, before and 2 weeks after LPI. Images were graded according to angle structures visible by an observer masked to clinical data or the status of LPI, and were performed in a random order. Angle closure in a quadrant was defined as the inability to visualize the posterior trabecular meshwork. We determined the number of quadrants with closed angles and the mean number of clock hours of angle closure before and after LPI in comparison to gonioscopy. Using EyeCam, all 24 eyes showed at least 1 quadrant of angle widening after LPI. The mean number of clock hours of angle closure decreased significantly, from 8.15 +/- 3.47 clock hours before LPI to 1.75 +/- 2.27 clock hours after LPI (P < .0001, Wilcoxon signed rank test). Overall, gonioscopy showed 1.0 +/- 1.41 (95% CI, 0.43-1.57) quadrants opening from closed to open after LPI compared to 2.0 +/- 1.28 (95% CI, 1.49-2.51, P = .009) quadrants with EyeCam. Intra-observer reproducibility of grading the extent of angle closure in clock hours in EyeCam images was moderate to good (intraclass correlation coefficient 0.831). EyeCam may be used to document changes in angle configuration after LPI in eyes with PACG. Copyright 2010 Elsevier Inc. All rights reserved.

Rates of short-GRB afterglows in association with binary neutron star mergers

NASA Astrophysics Data System (ADS)

Saleem, M.; Pai, Archana; Misra, Kuntal; Resmi, L.; Arun, K. G.

2018-03-01

Assuming all binary neutron star (BNS) mergers produce short gamma-ray bursts, we combine the merger rates of BNS from population synthesis studies, the sensitivities of advanced gravitational wave (GW) interferometer networks, and of the electromagnetic (EM) facilities in various wavebands, to compute the detection rate of associated afterglows in these bands. Using the inclination angle measured from GWs as a proxy for the viewing angle and assuming a uniform distribution of jet opening angle between 3° and 30°, we generate light curves of the counterparts using the open access afterglow hydrodynamics package BOXFIT for X-ray, optical, and radio bands. For different EM detectors, we obtain the fraction of EM counterparts detectable in these three bands by imposing appropriate detection thresholds. In association with BNS mergers detected by five (three) detector networks of advanced GW interferometers, assuming a BNS merger rate of 0.6-774 Gpc-3 yr-1 from population synthesis models, we find the afterglow detection rates (per year) to be 0.04-53 (0.02-27), 0.03-36 (0.01-19), and 0.04-47 (0.02-25) in the X-ray, optical, and radio bands, respectively. Our rates represent maximum possible detections for the given BNS rate since we ignore effects of cadence and field of view in EM follow-up observations.

Anterior Segment Morphology in Primary Angle Closure Glaucoma using Ultrasound Biomicroscopy

PubMed Central

Balakrishna, Nagalla

2017-01-01

Aim To evaluate the configuration of the anterior chamber angle quantitatively and study the morphological changes in the eye with ultrasound biomicroscopy (UBM) in primary angle closure glaucoma (PACG) patients after laser peripheral iridotomy (LPI). Materials and methods A total of 185 eyes of 185 PACG patients post-LPI and 126 eyes of 126 normal subjects were included in this prospective study. All subjects underwent complete ophthalmic evaluation, A-scan biometry, and UBM. The anterior segment and angle parameters were measured quantitatively and compared in both groups using Student’s t-test. Results The PACG patients had shorter axial length, shallower central anterior chamber depth anterior chamber depth (ACD), and anteriorly located lens when compared with normal subjects. Trabecular iris angle (TIA) was significantly narrow (5.73 ± 7.76°) in patients with PACG when compared with normal subjects (23.75 ± 9.38°). The angle opening distance at 500 pm from scleral spur (AOD 500), trabecular-ciliary process distance (TCPD), iris-ciliary process distance (ICPD), and iris-zonule distance (IZD) were significantly shorter in patients with PACG than in normal subjects (p < 0.0001). The iris lens angle (ILA), scleral-iris angle (SIA), and scleral-ciliary process angle (SCPA) were significantly narrower in patients with PACG than in normal subjects (p < 0.0001). The iris-lens contact distance (ILCD) was greater in PACG group than in normal (p = 0.001). Plateau iris was seen in 57/185 (30.8%) of the eyes. Anterior positioned ciliary processes were seen in 130/185 eyes (70.3%) of eyes. Conclusion In PACG patients, persistent apposition angle closure is common even after LPI, which could be due to anterior rotation of ciliary body and plateau iris and overcrowding of anterior segment due to shorter axial length and relative anterior lens position. How to cite this article: Mansoori T, Balakrishna N. Anterior Segment Morphology in Primary Angle Closure Glaucoma using Ultrasound Biomicroscopy. J Curr Glaucoma Pract 2017;11(3):86-91. PMID:29151682

Factors associated with lifetime risk of open-angle glaucoma blindness.

PubMed

Peters, Dorothea; Bengtsson, Boel; Heijl, Anders

2014-08-01

To investigate factors associated with bilateral glaucoma blindness, particularly factors available at the time of diagnosis. Retrospective chart review of all patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PEXG) followed at the Department of Ophthalmology or Low Vision Center of Skåne University Hospital, Malmö, Sweden, who died between January 2006 and June 2010. Disease stage at diagnosis was defined by a simplified version of Mills' glaucoma staging system using perimetric mean deviation (MD) to define six stages of severity. Blindness was defined according to WHO criteria. We used logistic regression analysis to examine the association between risk factors and glaucoma blindness. Four hundred and 23 patients were included; 60% POAG and 40% PEXG. Sixty-four patients (15%) became blind from glaucoma. Blind patients had significantly longer mean duration with diagnosed disease than patients who did not go blind (14.8 years ± 5.8 versus 10.6 years ± 6.5, p < 0.001). The risk of blindness increased with higher intraocular pressure (IOP) (OR 1.08, 95% CI 1.03-1.13) and with each stage of more advanced field loss at time of diagnosis (OR 1.80 95% CI 1.34-2.41). Older age at death was also associated with an increased risk of blindness (OR 1.09 95% CI 1.03-1.14), while age at diagnosis was unimportant. PEXG was not an independent risk factor for blindness. Higher IOP and worse visual field status at baseline were important risk factors, as was older age at death. © 2013 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Advances in Fatigue and Fracture Mechanics Analyses for Aircraft Structures

NASA Technical Reports Server (NTRS)

Newman, J. C., Jr.

1999-01-01

This paper reviews some of the advances that have been made in stress analyses of cracked aircraft components, in the understanding of the fatigue and fatigue-crack growth process, and in the prediction of residual strength of complex aircraft structures with widespread fatigue damage. Finite-element analyses of cracked structures are now used to determine accurate stress-intensity factors for cracks at structural details. Observations of small-crack behavior at open and rivet-loaded holes and the development of small-crack theory has lead to the prediction of stress-life behavior for components with stress concentrations under aircraft spectrum loading. Fatigue-crack growth under simulated aircraft spectra can now be predicted with the crack-closure concept. Residual strength of cracked panels with severe out-of-plane deformations (buckling) in the presence of stiffeners and multiple-site damage can be predicted with advanced elastic-plastic finite-element analyses and the critical crack-tip-opening angle (CTOA) fracture criterion. These advances are helping to assure continued safety of aircraft structures.

Advances in Fatigue and Fracture Mechanics Analyses for Metallic Aircraft Structures

NASA Technical Reports Server (NTRS)

Newman, J. C., Jr.

2000-01-01

This paper reviews some of the advances that have been made in stress analyses of cracked aircraft components, in the understanding of the fatigue and fatigue-crack growth process, and in the prediction of residual strength of complex aircraft structures with widespread fatigue damage. Finite-element analyses of cracked metallic structures are now used to determine accurate stress-intensity factors for cracks at structural details. Observations of small-crack behavior at open and rivet-loaded holes and the development of small-crack theory has lead to the prediction of stress-life behavior for components with stress concentrations under aircraft spectrum loading. Fatigue-crack growth under simulated aircraft spectra can now be predicted with the crack-closure concept. Residual strength of cracked panels with severe out-of-plane deformations (buckling) in the presence of stiffeners and multiple-site damage can be predicted with advanced elastic-plastic finite-element analyses and the critical crack-tip-opening angle (CTOA) fracture criterion. These advances are helping to assure continued safety of aircraft structures.

Role of oxidative stress enzymes in open-angle glaucoma.

PubMed

Yildirim, O; Ateş, N A; Ercan, B; Muşlu, N; Unlü, A; Tamer, L; Atik, U; Kanik, A

2005-05-01

To investigate the role of oxidative stress and lipid peroxidation in the pathogenesis of primary open-angle glaucoma (POAG). The activities of myeloperoxidase (MPO), catalase (CAT), and the levels of plasma malondialdehyde (MDA) were measured in 40 (15 men and 25 women) patients with POAG and 60 (30 men and 30 women) healthy controls. There was no significant difference in the activities of CAT and MPO between the POAG patients and the controls. However, the plasma MDA level was significantly higher in patients than the controls. The results of this preliminary study suggest that the possible alterations of plasma MDA levels may be associated with the pathogenesis of POAG, but further research is needed to understand the role of oxidative damage in this important disorder of aging.

Slow relaxation in weakly open rational polygons.

PubMed

Kokshenev, Valery B; Vicentini, Eduardo

2003-07-01

The interplay between the regular (piecewise-linear) and irregular (vertex-angle) boundary effects in nonintegrable rational polygonal billiards (of m equal sides) is discussed. Decay dynamics in polygons (of perimeter P(m) and small opening Delta) is analyzed through the late-time survival probability S(m) approximately equal t(-delta). Two distinct slow relaxation channels are established. The primary universal channel exhibits relaxation of regular sliding orbits, with delta=1. The secondary channel is given by delta>1 and becomes open when m>P(m)/Delta. It originates from vertex order-disorder dual effects and is due to relaxation of chaoticlike excitations.

Experimental investigation into wing span and angle-of-attack effects on sub-scale race car wing/wheel interaction aerodynamics

NASA Astrophysics Data System (ADS)

Diasinos, S.; Gatto, A.

2008-09-01

This paper details a quantitative 3D investigation using LDA into the interaction aerodynamics on a sub-scale open wheel race car inverted front wing and wheel. Of primary importance to this study was the influence of changing wing angle of attack and span on the resulting near-field and far-field flow characteristics. Results obtained showed that both variables do have a significant influence on the resultant flow-field, particularly on wing vortex and wheel wake development and propagation.

Longitudinal Changes of Angle Configuration in Primary Angle-Closure Suspects

PubMed Central

Jiang, Yuzhen; Chang, Dolly S.; Zhu, Haogang; Khawaja, Anthony P.; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M.

2015-01-01

Objective To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Design Longitudinal cohort study. Participants Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Methods Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Main Outcome Measures Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. Results No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8–1.6) in treated eyes and 1.6°/year (95% CI, 1.3–2.0) in untreated eyes (P<0.001). Conclusions Angle width of treated eyes increased markedly after LPI, remained stable for 6 months, and then decreased significantly by 18 months after LPI. Untreated eyes experienced a more consistent and rapid decrease in angle width over the same time period. PMID:24835757

Recent advances in the UltraScan SOlution MOdeller (US-SOMO) hydrodynamic and small-angle scattering data analysis and simulation suite.

PubMed

Brookes, Emre; Rocco, Mattia

2018-03-28

The UltraScan SOlution MOdeller (US-SOMO) is a comprehensive, public domain, open-source suite of computer programs centred on hydrodynamic modelling and small-angle scattering (SAS) data analysis and simulation. We describe here the advances that have been implemented since its last official release (#3087, 2017), which are available from release #3141 for Windows, Linux and Mac operating systems. A major effort has been the transition from the legacy Qt3 cross platform software development and user interface library to the modern Qt5 release. Apart from improved graphical support, this has allowed the direct implementation of the newest, almost two-orders of magnitude faster version of the ZENO hydrodynamic computation algorithm for all operating systems. Coupled with the SoMo-generated bead models with overlaps, ZENO provides the most accurate translational friction computations from atomic-level structures available (Rocco and Byron Eur Biophys J 44:417-431, 2015a), with computational times comparable with or faster than those of other methods. In addition, it has allowed us to introduce the direct representation of each atom in a structure as a (hydrated) bead, opening interesting new modelling possibilities. In the small-angle scattering (SAS) part of the suite, an indirect Fourier transform Bayesian algorithm has been implemented for the computation of the pairwise distance distribution function from SAS data. Finally, the SAS HPLC module, recently upgraded with improved baseline correction and Gaussian decomposition of not baseline-resolved peaks and with advanced statistical evaluation tools (Brookes et al. J Appl Cryst 49:1827-1841, 2016), now allows automatic top-peak frame selection and averaging.

Risk Factors Associated with Progression to Blindness from Primary Open-Angle Glaucoma in an African-American Population

PubMed Central

Pleet, Alexander; Sulewski, Melanie; Salowe, Rebecca J.; Fertig, Raymond; Salinas, Julia; Rhodes, Allison; Merritt, William; Natesh, Vikas; Huang, Jiayan; Gudiseva, Harini V.; Collins, David W.; Chavali, Venkata Ramana Murthy; Tapino, Paul; Lehman, Amanda; Regina-Gigiliotti, Meredith; Miller-Ellis, Eydie; Sankar, Prithvi; Ying, Gui-Shuang; O’Brien, Joan M.

2016-01-01

Purpose To determine the risk factors associated with progression to blindness from primary open-angle glaucoma (POAG) in an African-American population. Methods This study examined 2119 patients enrolled in the Primary Open-Angle African-American Glaucoma Genetics (POAAGG) study. A total of 59 eyes were identified as legally blind as a result of POAG (cases) and were age-and sex-matched to 59 non-blind eyes with glaucoma (controls). Chart reviews were performed to record known and suspected risk factors. Results Cases were diagnosed with POAG at an earlier age than controls (p = 0.005). Of the 59 eyes of cases, 16 eyes (27.1%) presented with blindness at diagnosis. Cases had worse visual acuity (VA) at diagnosis (p < 0.0001), with VA worse than 20/40 conferring a 27 times higher risk of progression to blindness (p = 0.0005). Blind eyes also demonstrated more visual field defects (p = 0.01), higher pretreatment intraocular pressure (IOP; p < 0.0001), and higher cup-to-disc ratio (p = 0.006) at diagnosis. IOP was less controlled in cases, and those with IOP ≥21 mmHg at more than 20% of follow-up visits were 73 times more likely to become blind (p < 0.0001). Cases missed a greater number of appointments per year (p = 0.003) and had non-adherence issues noted in their charts more often than controls (p = 0.03). However, other compliance data did not significantly differ between groups. Conclusion Access to care, initial VA worse than 20/40, and poor control of IOP were the major risk factors associated with blindness from POAG. Future studies should examine earlier, more effective approaches to glaucoma screening as well as the role of genetics in these significantly younger patients who progress to blindness. PMID:27348239

Glaucoma incidence in an unselected cohort of diabetic patients: is diabetes mellitus a risk factor for glaucoma? DARTS/MEMO collaboration. Diabetes Audit and Research in Tayside Study. Medicines Monitoring Unit.

PubMed

Ellis, J D; Evans, J M; Ruta, D A; Baines, P S; Leese, G; MacDonald, T M; Morris, A D

2000-11-01

To evaluate whether diabetes mellitus is a risk factor for the development of primary open angle glaucoma or ocular hypertension (OHT). A historical cohort study of an unselected population comprising all residents of the Tayside region of Scotland was performed using record linkage techniques followed by case note review. Ascertainment of prevalent diabetes was achieved using the Diabetes Audit and Research in Tayside Study (DARTS) validated regional diabetes register. Glaucoma and treated OHT were defined by encashment of community prescriptions and the statutory surgical procedure coding database. The study population comprised 6631 diabetic subjects and 166 144 non-diabetic subjects aged >40 years without glaucoma or OHT at study entry. 65 patients with diabetes and 958 without diabetes were identified as new cases of glaucoma or treated OHT during the 24 month study period, yielding a standardised morbidity ratio of 127 (95% CI, 96-158). Case note review demonstrated non-differential misclassification of prevalent glaucoma and OHT as incident disease (diabetic cohort 20%, non-diabetic cohort 24%; p=0.56) primarily as a result of non-compliance in medically treated disease. Removing misclassified cases and adjusting for age yielded an incidence of primary open angle glaucoma in diabetes of 1.1/1000 patient years (95% CI, 0.89-1. 31) compared to 0.7/1000 patient years (95% CI, 0.54-0.86) in the non-diabetic cohort; RR 1.57 (95% CI, 0.99-2.48). This study failed to confirm an association between diabetes mellitus and primary open angle glaucoma and ocular hypertension. A non-significant increase in diagnosed and treated disease in the diabetic population was observed, but evidence was also found that detection bias contributes to this association.

The Advanced Glaucoma Intervention Study (AGIS): 3. Baseline characteristics of black and white patients.

PubMed

1998-07-01

The purpose of this report is to examine the differences at baseline in demographic, medical, and ophthalmic characteristics between blacks and whites enrolled in the Advanced Glaucoma Intervention Study (AGIS), a multicenter, randomized, clinical trial. Multicenter, randomized, controlled trial. A total of 332 black patients (451 eyes), 249 white patients (325 eyes), and 10 patients of other races (13 eyes) with open-angle glaucoma that could not be controlled by medical therapy alone participated. There was no intervention performed. The investigators compare the baseline demographic, medical, and ophthalmic characteristics of black and white patients, adjusting the comparisons for age and gender. Blacks in the study were younger than whites and had more systemic hypertension and diabetes than whites. The visual field defects of blacks on average were substantially more severe than those of whites. Intraocular pressures and visual acuity scores were similar in the two groups. Blacks were more hyperopic and had relatively fewer disk rim hemorrhages than whites. The findings of the current study concur with those of previous clinical studies of open-angle glaucoma that visual field defects are more severe in blacks than whites.

Agreement of glaucoma specialists and experienced optometrists in gonioscopy and optic disc evaluation

PubMed Central

Kumar, Addepalli U.; Jonnadula, Ganesh B.; Garudadri, Chandrasekhar; Rao, Harsha L.; Senthil, Sirisha; Papas, Eric B.; Sankaridurg, Padmaja; Khanna, Rohit C.

2013-01-01

Purpose To compare the diagnostic performance of glaucoma specialists and experienced optometrists in gonioscopy and optic disc assessment. Methods This study was done to validate the diagnostic performance of two experienced optometrists for using their skills of detecting glaucoma using gonioscopy and optic disc assessment in a major epidemiological study, the L V Prasad Eye Institute Glaucoma Epidemiology and Molecular Genetics Study (LVPEI-GLEAMS). Gonioscopic findings for 150 eyes were categorized as 0, 1 and 2 for open angle, primary angle closure suspect (PACS) and primary angle closure (PAC) respectively. Optic disc findings for 200 eyes were categorized as 0, 1 and 2 for normal, suspects and glaucomatous respectively. Weighted kappa (κ) and diagnostic accuracy parameters were calculated. Two optometrists (#1 and #2) participated in the study. Results Agreement between glaucoma specialists and optometrist for interpretation of gonioscopy to discriminate PACS and PAC from open angles and for interpretation of optic disc to discriminate glaucomatous and suspicious discs from normal, the kappa (κ) was 0.92 and 0.84 and 0.90 and 0.89 for optometrists #1 and #2 respectively. Sensitivities and specificities were above 90% for gonioscopy. Optic disc evaluation had specificities greater than 95% to discriminate normal from glaucomatous discs while the sensitivities were 83% and 93% for optometrists #1 and #2 respectively. Conclusion Agreement between optometrists and glaucoma specialists, in diagnostic performance of gonioscopy and optic assessment was excellent with high sensitivity and specificity. Hence, we conclude that the experienced optometrists can detect glaucoma accurately in the LVPEI-GLEAMS.

Diagnostic ability of peripapillary vessel density measurements of optical coherence tomography angiography in primary open-angle and angle-closure glaucoma.

PubMed

Rao, Harsha L; Kadambi, Sujatha V; Weinreb, Robert N; Puttaiah, Narendra K; Pradhan, Zia S; Rao, Dhanaraj A S; Kumar, Rajesh S; Webers, Carroll A B; Shetty, Rohit

2017-08-01

To evaluate the diagnostic ability of peripapillary vessel density measurements on optical coherence tomography angiography (OCTA) in primary open-angle glaucoma (POAG) and primary angle-closure glaucoma (PACG), and to compare these with peripapillary retinal nerve fibre layer (RNFL) thickness measurements. In a cross-sectional study, 48 eyes of 33 healthy control subjects, 63 eyes of 39 patients with POAG and 49 eyes of 32 patients with PACG underwent OCTA (RTVue-XR, Optovue, Fremont, California, USA) and RNFL imaging with spectral domain OCT. Diagnostic abilities of vessel density and RNFL parameters were evaluated using area under receiver operating characteristic curves (AUC) and sensitivities at fixed specificities. AUCs of peripapillary vessel density ranged between 0.48 for the temporal sector and 0.88 for the inferotemporal sector in POAG. The same in PACG ranged between 0.57 and 0.86. Sensitivities at 95% specificity ranged from 13% to 70% in POAG, and from 10% to 67% in PACG. AUCs of peripapillary RNFL thickness ranged between 0.51 for the temporal sector and 0.91 for the inferonasal sector in POAG. The same in PACG ranged between 0.61 and 0.87. Sensitivities at 95% specificity ranged from 8% to 68% in POAG, and from 2% to 67% in PACG. AUCs of all peripapillary vessel density measurements were comparable (p>0.05) to the corresponding RNFL thickness measurements in both POAG and PACG. Diagnostic ability of peripapillary vessel density parameters of OCTA, especially the inferotemporal sector measurement, was good in POAG and PACG. Diagnostic abilities of vessel density measurements were comparable to RNFL measurements in both POAG and PACG. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

A Population-based survey of the prevalence and types of glaucoma in Nigeria: results from the Nigeria National Blindness and Visual Impairment Survey.

PubMed

Kyari, Fatima; Entekume, Gabriel; Rabiu, Mansur; Spry, Paul; Wormald, Richard; Nolan, Winifred; Murthy, Gudlavalleti V S; Gilbert, Clare E

2015-12-12

Glaucoma is the leading cause of irreversible blindness worldwide. There tends to be a lower reporting of glaucoma in Africa compared to other blinding conditions in global burden data. Research findings of glaucoma in Nigeria will significantly increase our understanding of glaucoma in Nigeria, in people of the West African diaspora and similar population groups. We determined the prevalence and types of glaucoma in Nigeria from the Nigeria National Blindness and Visual Impairment cross-sectional Survey of adults aged ≥40 years. Multistage stratified cluster random sampling with probability-proportional-to-size procedures were used to select a nationally representative sample of 15,027 persons aged ≥40 years. Participants had logMAR visual acuity measurement, FDT visual function testing, autorefraction, A-scan biometry and optic disc assessment. Participants with visual acuity of worse than 6/12 or suspicious optic discs had detailed examination including Goldmann applanation tonometry, gonioscopy and fundus photography. Disc images were graded by Moorfields Eye Hospital Reading Centre. Glaucoma was defined using International Society of Geographical and Epidemiological Ophthalmology criteria; and classified into primary open-angle or primary angle-closure or secondary glaucoma. Diagnosis of glaucoma was based on ISGEO classification. The type of glaucoma was determined by gonioscopy. A total of 13,591 participants in 305 clusters were examined (response rate 90.4 %). Optic disc grading was available for 25,289 (93 %) eyes of 13,081 (96 %) participants. There were 682 participants with glaucoma; a prevalence of 5.02 % (95 % CI 4.60-5.47). Among those with definite primary glaucoma that had gonioscopy (n = 243), open-angle glaucoma was more common (86 %) than angle-closure glaucoma (14 %). 8 % of glaucoma was secondary with the commonest causes being couching (38 %), trauma (21 %) and uveitis (19 %). Only 5.6 % (38/682) of participants with glaucoma knew they had the condition. One in every 5 persons with glaucoma (136;20 %) was blind i.e., visual acuity worse than 3/60. Nigeria has a high prevalence of glaucoma which is largely open-angle glaucoma. A high proportion of those affected are blind. Secondary glaucoma was mostly as a consequence of procedures for cataract. Public health control strategies and high quality glaucoma care service will be required to reduce morbidity and blindness from glaucoma.

Longitudinal changes of angle configuration in primary angle-closure suspects: the Zhongshan Angle-Closure Prevention Trial.

PubMed

Jiang, Yuzhen; Chang, Dolly S; Zhu, Haogang; Khawaja, Anthony P; Aung, Tin; Huang, Shengsong; Chen, Qianyun; Munoz, Beatriz; Grossi, Carlota M; He, Mingguang; Friedman, David S; Foster, Paul J

2014-09-01

To determine longitudinal changes in angle configuration in the eyes of primary angle-closure suspects (PACS) treated by laser peripheral iridotomy (LPI) and in untreated fellow eyes. Longitudinal cohort study. Primary angle-closure suspects aged 50 to 70 years were enrolled in a randomized, controlled clinical trial. Each participant was treated by LPI in 1 randomly selected eye, with the fellow eye serving as a control. Angle width was assessed in a masked fashion using gonioscopy and anterior segment optical coherence tomography (AS-OCT) before and at 2 weeks, 6 months, and 18 months after LPI. Angle width in degrees was calculated from Shaffer grades assessed under static gonioscopy. Angle configuration was also evaluated using angle opening distance (AOD250, AOD500, AOD750), trabecular-iris space area (TISA500, TISA750), and angle recess area (ARA) measured in AS-OCT images. No significant difference was found in baseline measures of angle configuration between treated and untreated eyes. At 2 weeks after LPI, the drainage angle on gonioscopy widened from a mean of 13.5° at baseline to a mean of 25.7° in treated eyes, which was also confirmed by significant increases in all AS-OCT angle width measures (P<0.001 for all variables). Between 2 weeks and 18 months after LPI, a significant decrease in angle width was observed over time in treated eyes (P<0.001 for all variables), although the change over the first 5.5 months was not statistically significant for angle width measured under gonioscopy (P = 0.18), AOD250 (P = 0.167) and ARA (P = 0.83). In untreated eyes, angle width consistently decreased across all follow-up visits after LPI, with a more rapid longitudinal decrease compared with treated eyes (P values for all variables ≤0.003). The annual rate of change in angle width was equivalent to 1.2°/year (95% confidence interval [CI], 0.8-1.6) in treated eyes and 1.6°/year (95% CI, 1.3-2.0) in untreated eyes (P<0.001). Angle width of treated eyes increased markedly after LPI, remained stable for 6 months, and then decreased significantly by 18 months after LPI. Untreated eyes experienced a more consistent and rapid decrease in angle width over the same time period. Copyright © 2014 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

First-line treatment for elevated intraocular pressure (IOP) associated with open-angle glaucoma or ocular hypertension: focus on bimatoprost

PubMed Central

Law, Simon K

2007-01-01

The goal of treatment for open-angle glaucoma or ocular hypertension is to improve quality of life through reduction of intraocular pressure (IOP) to preserve visual function. Prostaglandins, as a newer class of ocular hypotensive agents, have been shown to be effective in IOP reduction by the primary mechanism of action of increase the uveoscleral outflow. Bimatoprost is a member this class, but different from the other members by having an ethyl amide group rather than an isopropyl ester at the C-1 carbon of the alpha chain. Bimatoprost used once daily has been shown to be more effect in IOP reduction than other classes of topical ocular hypotensive agents including beta-blockers, carbonic anhydrase inhibitors, and alpha agonists. Comparing with other topical prostaglandins, bimatoprost may be slightly more effective in IOP reduction, but the clinical significance is uncertain. The commonly reported adverse events associated with bimatoprost are localized to the eye and include conjunctival hyperemia, changes in the pigmentation of the periocular skin and iris, and eyelash darkening and growth. It is currently approved by the Food and Drug Administration (FDA) and the European Commission (EC) for first-line therapy for the reduction of elevated IOP in patients with open-angle glaucoma or ocular hypertension. PMID:19668476

Clinical and Anterior Segment Anatomical Features in Primary Angle Closure Subgroups Based on Configurations of Iris Root Insertion.

PubMed

Hong, Ji Wook; Yun, Sung-Cheol; Sung, Kyung Rim; Lee, Jong Eun

2016-06-01

To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion. Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT0, IT500, IT750, and IT1500), lens vault, iris area, angle opening distance (AOD500), angle recess area (ARA750), and trabecular iris space area (TISA750) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG). In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT0 (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm(2), p = 0.045), lower ARA750 (0.112 ± 0.08 vs. 0.154 ± 0.08 mm(2), p = 0.017) and AOD500 (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG. The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Prevalence, types and awareness of glaucoma in a multi-ethnic population in rural China: the Yunnan Minority Eye Study.

PubMed

Pan, Chen-Wei; Zhao, Chun-Hua; Yu, Min-Bin; Cun, Qing; Chen, Qin; Shen, Wei; Li, Jun; Xu, Jian-Gang; Yuan, Yuansheng; Zhong, Hua

2016-11-01

To determine the prevalence, types and awareness of glaucoma in a rural community in China and to examine possible ethnic variations. The Yunnan Minority Eye Study was a multi-ethnic community-based eye survey using random cluster sampling strategies. 2133 Bai, 2205 Han and 2208 Yi Chinese aged 50 years or older participated in this study. Glaucoma including primary open-angle glaucoma (POAG), primary angle-closure glaucoma (PACG) and secondary glaucoma was defined based on the International Society of Geographical and Epidemiological Ophthalmology criteria. The overall age-standardized prevalence of all glaucoma was 2.6% (95% confidence interval [CI]: 2.2-3.1%) in this population. It was 1.8% (95% CI: 1.1-1.9%) for POAG and 0.5% (95% CI: 0.9-1.6%) for PACG, respectively. Among 29 people with secondary glaucoma, 27 (93%) were blind in at least one eye. The presence of primary open-angle glaucoma was associated with male gender (odds ratio [OR] = 2.94; comparing men with women), Yi ethnicity (OR = 2.27; comparing Yi with Han people), higher IOP (OR = 1.09 per mmHg increase), and the presence of myopia (OR = 1.84). Of the 212 participants with glaucoma, only 38 (18%) were aware of the disease and had been diagnosed previously as having glaucoma or suspected glaucoma. Patients who were better educated tended to be aware of the disease. Significant ethnic difference in the prevalence of POAG was observed in this study. The low awareness of glaucoma highlights the pressing need to increase public awareness of this potentially blinding condition in rural China. © 2016 The Authors Ophthalmic & Physiological Optics © 2016 The College of Optometrists.

Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial.

PubMed

Azuara-Blanco, Augusto; Burr, Jennifer; Ramsay, Craig; Cooper, David; Foster, Paul J; Friedman, David S; Scotland, Graham; Javanbakht, Mehdi; Cochrane, Claire; Norrie, John

2016-10-01

Primary angle-closure glaucoma is a leading cause of irreversible blindness worldwide. In early-stage disease, intraocular pressure is raised without visual loss. Because the crystalline lens has a major mechanistic role, lens extraction might be a useful initial treatment. From Jan 8, 2009, to Dec 28, 2011, we enrolled patients from 30 hospital eye services in five countries. Randomisation was done by a web-based application. Patients were assigned to undergo clear-lens extraction or receive standard care with laser peripheral iridotomy and topical medical treatment. Eligible patients were aged 50 years or older, did not have cataracts, and had newly diagnosed primary angle closure with intraocular pressure 30 mm Hg or greater or primary angle-closure glaucoma. The co-primary endpoints were patient-reported health status, intraocular pressure, and incremental cost-effectiveness ratio per quality-adjusted life-year gained 36 months after treatment. Analysis was by intention to treat. This study is registered, number ISRCTN44464607. Of 419 participants enrolled, 155 had primary angle closure and 263 primary angle-closure glaucoma. 208 were assigned to clear-lens extraction and 211 to standard care, of whom 351 (84%) had complete data on health status and 366 (87%) on intraocular pressure. The mean health status score (0·87 [SD 0·12]), assessed with the European Quality of Life-5 Dimensions questionnaire, was 0·052 higher (95% CI 0·015-0·088, p=0·005) and mean intraocular pressure (16·6 [SD 3·5] mm Hg) 1·18 mm Hg lower (95% CI -1·99 to -0·38, p=0·004) after clear-lens extraction than after standard care. The incremental cost-effectiveness ratio was £14 284 for initial lens extraction versus standard care. Irreversible loss of vision occurred in one participant who underwent clear-lens extraction and three who received standard care. No patients had serious adverse events. Clear-lens extraction showed greater efficacy and was more cost-effective than laser peripheral iridotomy, and should be considered as an option for first-line treatment. Medical Research Council. Copyright © 2016 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.

Effects of polymorphisms in vitamin E-, vitamin C-, and glutathione peroxidase-related genes on serum biomarkers and associations with glaucoma

USDA-ARS?s Scientific Manuscript database

To study the association of selected polymorphism in genes related to vitamin E, vitamin C, and glutathione peroxidase with these biomarkers and primary open-angle glaucoma (POAG) risk. A case-control study matched for age, sex, and bodyweight was undertaken. Two hundred fifty POAG cases and 250 con...

Correlation of pattern reversal visual evoked potential parameters with the pattern standard deviation in primary open angle glaucoma.

PubMed

Kothari, Ruchi; Bokariya, Pradeep; Singh, Ramji; Singh, Smita; Narang, Purvasha

2014-01-01

To evaluate whether glaucomatous visual field defect particularly the pattern standard deviation (PSD) of Humphrey visual field could be associated with visual evoked potential (VEP) parameters of patients having primary open angle glaucoma (POAG). Visual field by Humphrey perimetry and simultaneous recordings of pattern reversal visual evoked potential (PRVEP) were assessed in 100 patients with POAG. The stimulus configuration for VEP recordings consisted of the transient pattern reversal method in which a black and white checker board pattern was generated (full field) and displayed on VEP monitor (colour 14″) by an electronic pattern regenerator inbuilt in an evoked potential recorder (RMS EMG EP MARK II). The results of our study indicate that there is a highly significant (P<0.001) negative correlation of P100 amplitude and a statistically significant (P<0.05) positive correlation of N70 latency, P100 latency and N155 latency with the PSD of Humphrey visual field in the subjects of POAG in various age groups as evaluated by Student's t-test. Prolongation of VEP latencies were mirrored by a corresponding increase of PSD values. Conversely, as PSD increases the magnitude of VEP excursions were found to be diminished.

Decreased paraoxonase1 activity and increased malondialdehyde and oxidative DNA damage levels in primary open angle glaucoma

PubMed Central

Mumcu, Ugur Yilmaz; Kocer, Ibrahim; Ates, Orhan; Alp, H. Hakan

2016-01-01

To investigate the malondialdehyde (MDA) levels, paraoxonase1 (PON1) activity and 8-hydroxy 2-deoxyguanosine (8-OHdG) levels in the primary open angle glaucoma (POAG) patient. Blood samples from 52 healthy individuals and 53 patients with POAG were analyzed for MDA and 8-OHdG by HPLC (high-performance liquid chromatography) and PON1 by spectrophotometry. The data obtained were analyzed statistically. MDA levels were 10.46±8.4 and 4.70±1.79 µmol; PON1 levels were 121±39.55 and 161.62±60.22 U/mL; and 8-OHdG values were 1.32±0.53/106 dG and 0.47±0.27/106 dG in the POAG patients and the control group, respectively. The difference was significant in MDA levels, 8-OHdG levels and PON1 activity in POAG patients in comparison with controls (P<0.001). We concluded that the observed increase in MDA and 8-OHdG levels may be correlated with decreased PON1 activity. Oxidative stress plays an important role in glaucoma development. PMID:27803873

Medical management of primary open-angle glaucoma: Best practices associated with enhanced patient compliance and persistency.

PubMed

Kulkarni, Sadhana V; Damji, Karim F; Buys, Yvonne M

2008-02-02

Primary open angle glaucoma is a chronic optic neuropathy often requiring lifelong treatment. Patient compliance, adherence and persistence with therapy play a vital role in improved outcomes by reducing morbidity and the economic consequences that are associated with disease progression. A literature review including searches of The Cochrane Library, MEDLINE, PubMed, conference proceedings, and bibliographies of identified articles reveals the enormous public health burden in various populations due to the impact of glaucoma associated visual impairment on the overall quality of life eg, fear of blindness, inability to work in certain occupations, driving restrictions, motor vehicle accidents, falls, and general health status. Providing specific definitions for the frequently misunderstood terms "compliance, persistence and adherence" with reference to medication use is central not only for monitoring patients' drug dosing histories and clinical outcomes but also for subsequent research. In this review article, a summary of the advantages/disadvantages including cost-effectiveness of various medical approaches to glaucoma treatment, techniques employed for measuring patient compliance and actual patient preferences for therapy are outlined. We conclude by identifying the key barriers to ongoing treatment and suggest some best practices to enhance compliance and persistence.

Medical management of primary open-angle glaucoma: Best practices associated with enhanced patient compliance and persistency

PubMed Central

Kulkarni, Sadhana V; Damji, Karim F; Buys, Yvonne M

2008-01-01

Primary open angle glaucoma is a chronic optic neuropathy often requiring lifelong treatment. Patient compliance, adherence and persistence with therapy play a vital role in improved outcomes by reducing morbidity and the economic consequences that are associated with disease progression. A literature review including searches of The Cochrane Library, MEDLINE, PubMed, conference proceedings, and bibliographies of identified articles reveals the enormous public health burden in various populations due to the impact of glaucoma associated visual impairment on the overall quality of life eg, fear of blindness, inability to work in certain occupations, driving restrictions, motor vehicle accidents, falls, and general health status. Providing specific definitions for the frequently misunderstood terms “compliance, persistence and adherence” with reference to medication use is central not only for monitoring patients’ drug dosing histories and clinical outcomes but also for subsequent research. In this review article, a summary of the advantages/disadvantages including cost-effectiveness of various medical approaches to glaucoma treatment, techniques employed for measuring patient compliance and actual patient preferences for therapy are outlined. We conclude by identifying the key barriers to ongoing treatment and suggest some best practices to enhance compliance and persistence. PMID:19920977

Interocular asymmetry of the visual field defects in newly diagnosed normal-tension glaucoma, primary open-angle glaucoma, and chronic angle-closure glaucoma.

PubMed

Huang, Ping; Shi, Yan; Wang, Xin; Liu, Mugen; Zhang, Chun

2014-09-01

To compare the interocular asymmetry of visual field loss in newly diagnosed normal-tension glaucoma (NTG), primary open-angle glaucoma (POAG), and chronic angle-closure glaucoma (CACG) patients. Visual field results of 117 newly diagnosed, treatment-naive glaucoma patients (42 NTG, 38 POAG, and 37 CACG) were studied retrospectively. The following 3 visual field defect parameters were used to evaluate the interocular asymmetry: (1) global indices; (2) local mean deviations (MDs) of 6 predefined visual field areas; and (3) stage designated by glaucoma staging system 2. The differences of the above parameters between the trial eye (the eye with greater MDs) and the fellow eye in each subject were defined as interocular asymmetry scores. Interocular asymmetry of visual field loss was presented in all the 3 groups (all P<0.05). CACG group had greater total MD interocular asymmetry score compared with the NTG and POAG groups (among groups, P=0.008; NTG vs. CACG, P=0.005; POAG vs. CACG, P=0.009). CACG also presented with significantly higher local MD interocular asymmetry scores at central, inferior, and temporal areas compared with those of the POAG group and at inferior area compared with that of NTG group. No significant difference in either total or local MDs was detected between NTG and POAG (all P>0.05). Interocular asymmetry scores of glaucoma staging system 2 had no significant difference among the 3 groups (P=0.068). All CACG, POAG, and NTG groups presented with interocular asymmetric visual field loss at the time of diagnosis. CACG had greater interocular asymmetry compared with NTG and POAG. No significant interocular asymmetry difference was observed between NTG and POAG.

EX-PRESS Glaucoma Filtration Device: efficacy, safety, and predictability

PubMed Central

Chan, Jessica E; Netland, Peter A

2015-01-01

Trabeculectomy has been the traditional primary surgical therapy for open-angle glaucoma. While trabeculectomy is effective in lowering intraocular pressure, complications associated with the procedure have motivated the development of alternative techniques and devices, including the EX-PRESS Glaucoma Filtration Device. This review describes the efficacy, safety, complication rates, and potential advantages and disadvantages of the EX-PRESS Glaucoma Filtration Device. EX-PRESS implantation is technically simpler compared with that of trabeculectomy, with fewer surgical steps. Vision recovery has been more rapid after EX-PRESS implantation compared with trabeculectomy. Intraocular pressure variation is lower during the early postoperative period, indicating a more predictable procedure. While efficacy of the EX-PRESS implant has been comparable to trabeculectomy, postoperative complications appear less common after EX-PRESS implantation compared with trabeculectomy. The EX-PRESS Glaucoma Filtration Device appears to be safe and effective in the surgical management of open-angle glaucoma. PMID:26366105

Stage of visual field loss and age at diagnosis in 1988 patients with different glaucomas: implications for glaucoma screening and driving ability.

PubMed

Gramer, Gwendolyn; Gramer, Eugen

2018-04-01

To compare stage of visual field loss (VFL) and age at diagnosis between patients with different types of glaucoma with regard to glaucoma screening and driving ability. In a cross-sectional study of 1988 consecutive patients with different types of glaucoma VFL at diagnosis and age at diagnosis were assessed. Patients with binocular advanced or severe VFL were classified unable, patients with no VFL in one eye and VFL I-V (Aulhorn classification) in the other eye able, all other constellations questionably able to drive. There were significant differences in age at diagnosis between different glaucomas and between patients with different stages of VFL at diagnosis. Age-related assessment of VFL at diagnosis in normal tension glaucoma (NTG) compared to primary open-angle glaucoma (POAG) showed that NTG is not a disease of the elderly but a disease with late diagnosis at severe VFL. In POAG a solely age-related glaucoma screening, e.g. from the age of 50 years, does not sufficiently lead to diagnosis at an early stage of the disease. In POAG solely based on binocular VFL 11.5% of patients were judged unable, 29.2% questionably able to drive, in NTG 19.6%/43.1%, pigmentary glaucoma 16%/22%, pseudoexfoliation glaucoma 9.1%/16.7%, and in primary angle-closure glaucoma 14.6%/30%. Depending on type of glaucoma more than 50% of patients require counselling regarding safe driving as part of clinical care. A disease-specific, age-related perimetric examination considering additional risk factors like family history of glaucoma is essential for early detection of glaucoma and road safety.

Functional Activity of Matrix Metalloproteinases 2 and 9 in Tears of Patients With Glaucoma.

PubMed

Sahay, Prity; Rao, Aparna; Padhy, Debananda; Sarangi, Sarada; Das, Gopinath; Reddy, Mamatha M; Modak, Rahul

2017-05-01

To evaluate the differential expression of tear matrix metalloproteinases (MMP) 2 and 9 in of patients with various forms of glaucoma. Tear samples were collected with a Schirmer's strip from 148 eyes of 113 patients (medically naïve patients with primary open-angle [POAG] or angle closure glaucoma [PACG] and those with pseudoexfoliation syndrome [PXF] or glaucoma [PXG]). These were compared to patients undergoing cataract surgery (controls) for this cross-sectional study. Functional activities of tear MMP-9 and MMP-2 were analyzed by gelatin zymography. Tenon's capsules (n = 15) were harvested from the inferior quadrant in those undergoing cataract surgery and protein expression of MMP-9 was analyzed by immunohistochemistry (IHC). Hydrogen peroxide (H2O2) stress-induced effects on in vitro activities of MMP-9 in human trabecular meshwork (HTM) cells were analyzed. The MMP-9 activity in tears was increased significantly in POAG, (n = 27), PACG (n = 24), and PXF (n = 40) eyes compared to controls (n = 35), and was increased significantly in eyes with glaucoma compared to moderate/severe glaucoma (P < 0.001). The MMP-9 expression was significantly lower in PXG (n = 22) eyes. Immunohistochemistry of Tenon's capsule revealed increased expression of MMP-9 in primary glaucoma eyes. Increased MMP-9 activity was seen in in vitro by gelatin zymography and was confirmed by Western and immunofluorescent assay on HTM upon 800 and 1000 μM H2O2-induced stress for 2 to 3 hours with approximately 80% cell death. Increased tear MMP-9 activity in early glaucoma and pseudoexfoliation syndrome suggesting activation of extracellular matrix (ECM) degradation can be used as a tear-based predictive biomarker. Decreased expression in advanced stages suggests exhaustion of the degradation response.

Glaucoma: Symptoms and Causes

MedlinePlus

... damage. The types of glaucoma include the following: Open-angle glaucoma Open-angle glaucoma is the most common form of ... angle formed by the cornea and iris remains open, but the trabecular meshwork is partially blocked. This ...

Patient-reported vision-related quality of life differences between superior and inferior hemifield visual field defects in primary open-angle glaucoma.

PubMed

Cheng, Hui-Chen; Guo, Chao-Yu; Chen, Mei-Ju; Ko, Yu-Chieh; Huang, Nicole; Liu, Catherine Jui-ling

2015-03-01

Previous studies have found that glaucoma is associated with impaired patient-reported vision-related quality of life (pVRQOL) but few, to our knowledge, have assessed how the visual field (VF) defect location impacts the pVRQOL. To investigate the associations of VF defects in the superior vs inferior hemifields with pVRQOL outcomes in patients with primary open-angle glaucoma. Prospective cross-sectional study at a tertiary referral center from March 1, 2012, to January 1, 2013, including patients with primary open-angle glaucoma who had a best-corrected visual acuity in the better eye equal to or better than 20/60 and reliable VF tests. The pVRQOL was assessed by a validated Taiwanese version of the 25-item National Eye Institute Visual Function Questionnaire. Reliable VF tests obtained within 3 months of enrollment were transformed to binocular integrated VF (IVF). The IVF was further stratified by VF location (superior vs inferior hemifield). The association between each domain of the 25-item National Eye Institute Visual Function Questionnaire and superior or inferior hemifield IVF was determined using multivariable linear regression analysis. The analysis included 186 patients with primary open-angle glaucoma with a mean age of 59.1 years (range, 19-86 years) and IVF mean deviation (MD) of -4.84 dB (range, -27.56 to 2.17 dB). In the multivariable linear regression analysis, the MD of the full-field IVF showed positive associations with near activities (β = 0.05; R2 = 0.20; P < .001), vision-specific role difficulties (β = 0.04; R2 = 0.19; P = .01), vision-specific dependency (β = 0.04; R2 = 0.20; P < .001), driving (β = 0.05; R2 = 0.24; P < .001), peripheral vision (β = 0.03; R2 = 0.18; P = .02), and composite scores (β = 0.04; R2 = 0.27; P = .005). Subsequent analysis showed that the MD of the superior hemifield IVF was associated only with near activities (β = 0.04; R2 = 0.21; P < .001) while the MD of the inferior hemifield IVF was associated with general vision (β = 0.04; R2 = 0.12; P = .01), vision-specific role difficulties (β = 0.04; R2 = 0.20; P = .01), and peripheral vision (β = 0.03; R2 = 0.17; P = .03). Superior hemifield IVF was strongly associated with difficulty with near activities. Inferior hemifield IVF impacted vision-specific role difficulties and general and peripheral vision. The impact of a VF defect on a patient's pVRQOL may depend not only on its severity, but also on its hemifield location.

Unit Advancement Flap for Lower Lip Reconstruction.

PubMed

Ogino, Akihiro; Onishi, Kiyoshi; Okada, Emi; Nakamichi, Miho

2018-05-01

Lower lip reconstruction requires consideration of esthetic and functional outcome in selecting a surgical procedure, and reconstruction with local tissue is useful. The authors reconstructed full-thickness defects with a unit advancement flap. Reconstruction was performed using this method in 4 patients with lower lip squamous cell carcinoma in whom tumor resection with preservation of the mouth angle was possible. The lower lip resection width was 30 to 45 mm, accounting for 50% to 68% of the entire width of the lower lip. The flap was prepared by lateral extension from above the mental unit and matched with the potential wrinkle line of the lower lip in order to design a unit morphology surrounded by the anterior margin of the depressor labii inferioris muscle. It was elevated as a full-thickness flap composed of the orbicularis oris muscle, skin, and mucosa of the residual lower lip from the bilateral sides, and advanced to the defect. Flap transfer was adjusted by small triangular resection of the skin on the lateral side of the mental unit. The postoperative scar was inconspicuous in all patients and there was no impairment of the mouth opening-closing or articulation functions. This was a relatively simple surgical procedure. A blood supply of the flap was stable, and continuity of the orbicularis oris muscle was reconstructed by transferred the residual lower lip advancement flap from the bilateral sides. The postoperative mouth opening-closing function was sufficient, and dentures could be placed from an early phase in elderly patients. The postoperative scar was consistent with the lip unit morphology, being esthetically superior. This procedure may be applicable for reconstruction of defects approximately 1/3 to 2/3 the width of the lower lip where the mouth angle is preserved.

Glaucoma Blindness at a Tertiary Eye Care Center.

PubMed

Stone, Jordan S; Muir, Kelly W; Stinnett, Sandra S; Rosdahl, Jullia A

2015-01-01

Glaucoma is an important cause of irreversible blindness. This study describes the characteristics of a large, diverse group of glaucoma patients and evaluates associations between demographic and clinical characteristics and blindness. Data were gathered via retrospective chart review of patients (N = 1,454) who were seen between July 2007 and July 2010 by glaucoma service providers at Duke Eye Center. Visual acuity and visual field criteria were used to determine whether patients met the criteria for legal blindness. Descriptive and comparative statistical analyses were performed on the glaucoma patients who were not blind (n = 1,258) and those who were blind (n = 196). A subgroup analysis of only those patients with primary open-angle glaucoma was also performed. In this tertiary care population, 13% (n = 196) of glaucoma patients met criteria for legal blindness, nearly one-half of whom (n = 94) were blind from glaucoma, and another one-third of whom (n = 69) had glaucoma-related blindness. The most common glaucoma diagnosis at all levels of vision was primary open-angle glaucoma. A larger proportion of black patients compared with white patients demonstrated vision loss; the odds ratio (OR) for blindness was 2.25 (95% CI, 1.6-3.2) for black patients compared with white patients. The use of systemic antihypertensive medications was higher among patients who were blind compared with patients who were not blind (OR = 2.1; 95% CI, 1.4-3.1). A subgroup analysis including only patients with primary open-angle glaucoma showed similar results for both black race and use of systemic antihypertensive medications. The relationship between use of systemic antihypertensive medications and blindness was not different between black patients and white patients (interaction P = .268). Data were based on chart review, and associations may be confounded by unmeasured factors. Treated systemic hypertension may be correlated with blindness, and the cause cannot be explained solely by race. In addition, this study demonstrated that there is continued disparity between black patients and white patients with regards to blindness from glaucoma. ©2015 by the North Carolina Institute of Medicine and The Duke Endowment. All rights reserved.

Glaucoma Blindness at a Tertiary Eye Care Center

PubMed Central

Stone, Jordan S.; Muir, Kelly W.; Stinnett, Sandra S.; Rosdahl, Jullia A.

2016-01-01

BACKGROUND Glaucoma is an important cause of irreversible blindness. This study describes the characteristics of a large, diverse group of glaucoma patients and evaluates associations between demographic and clinical characteristics and blindness. METHODS Data were gathered via retrospective chart review of patients (N = 1,454) who were seen between July 2007 and July 2010 by glaucoma service providers at Duke Eye Center. Visual acuity and visual field criteria were used to determine whether patients met the criteria for legal blindness. Descriptive and comparative statistical analyses were performed on the glaucoma patients who were not blind (n = 1,258) and those who were blind (n = 196). A subgroup analysis of only those patients with primary open-angle glaucoma was also performed. RESULTS In this tertiary care population, 13% (n = 196) of glaucoma patients met criteria for legal blindness, nearly one-half of whom (n = 94) were blind from glaucoma, and another one-third of whom (n = 69) had glaucoma-related blindness. The most common glaucoma diagnosis at all levels of vision was primary open-angle glaucoma. A larger proportion of black patients compared with white patients demonstrated vision loss; the odds ratio (OR) for blindness was 2.25 (95% CI, 1.6–3.2) for black patients compared with white patients. The use of systemic antihypertensive medications was higher among patients who were blind compared with patients who were not blind (OR = 2.1; 95% CI, 1.4–3.1). A subgroup analysis including only patients with primary open-angle glaucoma showed similar results for both black race and use of systemic antihypertensive medications. The relationship between use of systemic antihypertensive medications and blindness was not different between black patients and white patients (interaction P = .268). LIMITATIONS Data were based on chart review, and associations may be confounded by unmeasured factors. CONCLUSIONS Treated systemic hypertension may be correlated with blindness, and the cause cannot be explained solely by race. In addition, this study demonstrated that there is continued disparity between black patients and white patients with regards to blindness from glaucoma. PMID:26509509

Prevalence of primary open-angle glaucoma in an urban south Indian population and comparison with a rural population. The Chennai Glaucoma Study.

PubMed

Vijaya, Lingam; George, Ronnie; Baskaran, M; Arvind, Hemamalini; Raju, Prema; Ramesh, S Ve; Kumaramanickavel, Govindasamy; McCarty, Catherine

2008-04-01

To estimate the prevalence and risk factors of primary open-angle glaucoma (POAG) in an urban population and compare the same with that of our published rural population data in southern India. Population-based cross-sectional study. Four thousand eight hundred subjects 40 years or older were selected using a multistage random cluster sampling procedure in Chennai city. Three thousand eight hundred fifty (80.2%) subjects underwent a complete ophthalmic examination, including applanation tonometry, gonioscopy, pachymetry, optic disc photography, and automated perimetry. Glaucoma was diagnosed using the International Society of Geographical and Epidemiological Ophthalmology Classification. The distribution of intraocular pressure (IOP) and vertical cup-to-disc ratio (VCDR) was obtained from the right eye of the 2532 subjects with normal suprathreshold visual fields. Mean IOP was 16.17+/-3.74 mmHg (97.5th and 99.5th percentiles, 24 mmHg and 30 mmHg). The mean VCDR was 0.43+/-0.17 (97.5th and 99.5th percentiles, 0.7 and 0.8). One hundred thirty-five (64 men, 71 women) subjects had POAG (3.51%; 95% confidence interval [CI], 3.04-4.0). Primary open-angle glaucoma subjects (58.4+/-11.3 years) were older (P<0.0001) than the study population (54.8+/-10.6 years). One hundred twenty-seven (94%) subjects were diagnosed to have POAG for the first time. Two subjects (1.5%) were bilaterally blind, and 3 (3.3%) were unilaterally blind due to POAG. The urban population prevalence was more than that of the rural population (1.62%; 95% CI, 1.4%-1.8%; P<0.0001). In both populations, increasing IOP (per millimeter of mercury) and older age were associated with the disease. There was no association with gender, myopia, systemic hypertension, diabetes, or central corneal thickness. The prevalence of POAG in a > or =40-year-old south Indian urban population was 3.51%, higher than that of the rural population. The prevalence increased with age, and >90% were not aware of the disease.

Open-angle glaucoma in patients with diabetic retinopathy at the Puerto Rico Medical Center.

PubMed

Cruz-lñigo, Yousef; Izquierdo, Natalio J; García, Omar; Pérez, Raúl

2012-01-01

The association of open-angle glaucoma (OAG) with diabetes mellitus remains controversial. We report on the frequency of open-angle glaucoma in patients having diabetic retinopathy in a population of the Puerto Rico Medical Center. A cross-sectional study of 1,442 patients was done. Only the chart of patients 40 years-of-age and older, with a diagnosis of diabetic retinopathy and/or open-angle glaucoma were included. Descriptive analysis was done. Unadjusted and gender-adjusted logistic regression analyses were used to estimate risk of developing open-angle glaucoma in patients with diabetic retinopathy for each subsequent decade. 1,040 patients were diagnosed with diabetic retinopathy from July 1, 2004 to June 30, 2009. Also, 402 patients were diagnosed with open-angle glaucoma from July 1, 2007 to June 30, 2009. Of the 1,040 patients with diabetic retinopathy, 64 patients (6.15%) also had OAG. According to our gender-adjusted logistic regression analysis the estimated risk of developing open-angle glaucoma for patients 40 years-of-age with diabetic retinopathy increased for each subsequent decade until the seventh decade, odds ratio = 5.07 (95% confidence interval: 1.62-15.86). Thereafter, it decreased, odds ratio = 2.07 (95% confidence interval: 0.36-11.82). Our findings suggest that Puerto Rico patients between 40 to 79 years of age with diabetic retinopathy have an increased risk of developing open-angle glaucoma with each subsequent decade. Screening for open-angle glaucoma in patients with diabetic retinopathy is of utmost importance in the aging Puerto Rico population to prevent blindness.

Hysteresis of Contact Angle of Sessile Droplets on Smooth Homogeneous Solid Substrates via Disjoining/Conjoining Pressure.

PubMed

Kuchin, I; Starov, V

2015-05-19

A theory of contact angle hysteresis of liquid droplets on smooth, homogeneous solid substrates is developed in terms of the shape of the disjoining/conjoining pressure isotherm and quasi-equilibrium phenomena. It is shown that all contact angles, θ, in the range θr < θ < θa, which are different from the unique equilibrium contact angle θ ≠ θe, correspond to the state of slow "microscopic" advancing or receding motion of the liquid if θe < θ < θa or θr < θ < θe, respectively. This "microscopic" motion almost abruptly becomes fast "macroscopic" advancing or receding motion after the contact angle reaches the critical values θa or θr, correspondingly. The values of the static receding, θr, and static advancing, θa, contact angles in cylindrical capillaries were calculated earlier, based on the shape of disjoining/conjoining pressure isotherm. It is shown now that (i) both advancing and receding contact angles of a droplet on a on smooth, homogeneous solid substrate can be calculated based on shape of disjoining/conjoining pressure isotherm, and (ii) both advancing and receding contact angles depend on the drop volume and are not unique characteristics of the liquid-solid system. The latter is different from advancing/receding contact angles in thin capillaries. It is shown also that the receding contact angle is much closer to the equilibrium contact angle than the advancing contact angle. The latter conclusion is unexpected and is in a contradiction with the commonly accepted view that the advancing contact angle can be taken as the first approximation for the equilibrium contact angle. The dependency of hysteresis contact angles on the drop volume has a direct experimental confirmation.

Results of tests of advanced flexible insulation vortex and flow environments in the North American Aerodynamics Laboratory lowspeed wind tunnel using 0.0405-scale Space Shuttle Orbiter model 16-0 (test OA-309)

NASA Technical Reports Server (NTRS)

Marshall, B. A.; Nichols, M. E.

1984-01-01

An experimental investigation (Test OA-309) was conducted using 0.0405-scale Space Shuttle Orbiter Model 16-0 in the North American Aerodynamics Laboratory 7.75 x 11.00-foot Lowspeed Wind Tunnel. The primary purpose was to locate and study any flow conditions or vortices that might have caused damage to the Advanced Flexible Reusable Surface Insulation (AFRSI) during the Space Transportation System STS-6 mission. A secondary objective was to evaluate vortex generators to be used for Wind Tunnel Test OS-314. Flowfield visualization was obtained by means of smoke, tufts, and oil flow. The test was conducted at Mach numbers between 0.07 and 0.23 and at dynamic pressures between 7 and 35 pounds per square foot. The angle-of-attack range of the model was -5 degrees through 35 degrees at 0 or 2 degrees of sideslip, while roll angle was held constant at zero degrees. The vortex generators were studied at angles of 0, 5, 10, and 15 degrees.

LDV Surveys Over a Fighter Model at Moderate to High Angles of Attack

NASA Technical Reports Server (NTRS)

Sellers, William L., III; Meyers, James F.; Hepner, Timothy E.

2004-01-01

The vortex flowfield over an advanced twin-tailed fighter configuration was measured in a low-speed wind tunnel at two angles of attack. The primary test data consisted of 3-component velocity surveys obtained using a Laser Doppler Velocimeter. Laser light sheet and surface flow visualization were also obtained to provide insight into the flowfield structure. Time-averaged velocities and the root mean square of the velocity fluctuations were obtained at two cross-sections above the model. At 15 degrees angle of attack, the vortices generated by the wing leading edge extension (LEX) were unburst over the model and passed outboard of the vertical tail. At 25 degrees angle of attack, the vortices burst in the vicinity of the wing-LEX intersection and impact directly on the vertical tails. The RMS levels of the velocity fluctuations reach values of approximately 30% in the region of the vertical tails.

Conceptual Design Studies of Composite AMST

DTIC Science & Technology

1974-10-01

WEIGHT OF THE AIRFRAME THE PROPERTIES OF HIGH -STRENGTH GRAPHITE-EPOXY COMPOSITES (REPRESENTATIVE OF THORNEL 300 FIBERS) WERE USED IN THE APPLICATION...The primary advanced composite material selected was a high -strength graphite-epoxy (Thornel 300/Narmco 5208). Boron-infiltrated aluminum extrusions...Figure Page 25 Trimming Irregular Cutouts in Wing Box Attach Angles ...... 71 26 Hydroforming W-Truss Web Beaded Panels ................ 72 27 Exploded

Orientation Dependence of Columnar Dendritic Growth with Sidebranching Behaviors in Directional Solidification: Insights from Phase-Field Simulations

NASA Astrophysics Data System (ADS)

Xing, Hui; Dong, Xianglei; Wang, Jianyuan; Jin, Kexin

2018-04-01

In this study, a thin-interface phase-field model was employed to study the orientation dependence of the columnar dendritic growth with sidebranching behaviors in directional solidification. It was found that the dimensionless tip undercooling increases with the increase of misorientation angle for three pulling velocities. The primary spacing is found to be a function of misorientation angle, and the dimensionless primary spacing with respect to the misorientation angle follows the orientation correction given by Gandin and Rappaz (Acta. Metall. 42:2233-2246, 1994). For the analysis of the dendritic tip, the two-dimensional (2-D) form of the nonaxisymmetric needle crystal was used to determine the radius of the tilted columnar dendrite. Based on the definitions of open side and constrained side of the dendrite, the analysis of the width active sidebranches and the dendritic area in 2-D with respect to the distance from the dendritic tip was carried out to investigate the asymmetrical dendrite envelop and sidebranching behaviors on the two sides in directional solidification. The obtained prefactor and exponent with respect to misorientation angle are discussed, showing that the sidebranching behaviors of a tilted columnar dendritic array obey a similar power-law relationship with that of a free dendritic growth.

The effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk

NASA Astrophysics Data System (ADS)

Han, Qinkai; Chu, Fulei

2012-12-01

It is well known that either the asymmetric disk or transverse crack brings parametric inertia (or stiffness) excitation to the rotor-bearing system. When both of them appear in a rotor system, the parametric instability behaviors have not gained sufficient attentions. Thus, the effect of transverse crack upon parametric instability of a rotor-bearing system with an asymmetric disk is studied. First, the finite element equations of motion are established for the asymmetric rotor system. Both the open and breathing transverse cracks are taken into account in the model. Then, the discrete state transition matrix (DSTM) method is introduced for numerically acquiring the instability regions. Based upon these, some computations for a practical asymmetric rotor system with open or breathing transverse crack are conducted, respectively. Variations of the primary and combination instability regions induced by the asymmetric disk with the crack depth are observed, and the effect of the orientation angle between the crack and asymmetric disk on various instability regions are discussed in detail. It is shown that for the asymmetric angle around 0, the existence of transverse (either open or breathing) crack has attenuation effect upon the instability regions. Under certain crack depth, the instability regions could be vanished by the transverse crack. When the asymmetric angle is around π/2, increasing the crack depth would enhance the instability regions.

Application of advanced shearing techniques to the calibration of autocollimators with small angle generators and investigation of error sources.

PubMed

Yandayan, T; Geckeler, R D; Aksulu, M; Akgoz, S A; Ozgur, B

2016-05-01

The application of advanced error-separating shearing techniques to the precise calibration of autocollimators with Small Angle Generators (SAGs) was carried out for the first time. The experimental realization was achieved using the High Precision Small Angle Generator (HPSAG) of TUBITAK UME under classical dimensional metrology laboratory environmental conditions. The standard uncertainty value of 5 mas (24.2 nrad) reached by classical calibration method was improved to the level of 1.38 mas (6.7 nrad). Shearing techniques, which offer a unique opportunity to separate the errors of devices without recourse to any external standard, were first adapted by Physikalisch-Technische Bundesanstalt (PTB) to the calibration of autocollimators with angle encoders. It has been demonstrated experimentally in a clean room environment using the primary angle standard of PTB (WMT 220). The application of the technique to a different type of angle measurement system extends the range of the shearing technique further and reveals other advantages. For example, the angular scales of the SAGs are based on linear measurement systems (e.g., capacitive nanosensors for the HPSAG). Therefore, SAGs show different systematic errors when compared to angle encoders. In addition to the error-separation of HPSAG and the autocollimator, detailed investigations on error sources were carried out. Apart from determination of the systematic errors of the capacitive sensor used in the HPSAG, it was also demonstrated that the shearing method enables the unique opportunity to characterize other error sources such as errors due to temperature drift in long term measurements. This proves that the shearing technique is a very powerful method for investigating angle measuring systems, for their improvement, and for specifying precautions to be taken during the measurements.

Comparing approaches to screening for angle closure in older Chinese adults

PubMed Central

Andrews, J; Chang, D S; Jiang, Y; He, M; Foster, P J; Munoz, B; Kashiwagi, K; Friedman, D S

2012-01-01

Aims Primary angle-closure glaucoma is expected to account for nearly 50% of bilateral glaucoma blindness by 2020. This study was conducted to assess the performance of the scanning peripheral anterior chamber depth analyzer (SPAC) and limbal anterior chamber depth (LACD) as screening methods for angle closure. Methods This study assessed two clinical populations to compare SPAC, LACD, and gonioscopy: the Zhongshan Angle-closure Prevention Trial, from which 370 patients were eligible as closed-angle participants and the Liwan Eye Study, from which 72 patients were selected as open-angle controls. Eligible participants were assessed by SPAC, LACD, and gonioscopy. Results Angle status was defined by gonioscopy. Area under the receiver operating characteristic curve (AUROC) for SPAC was 0.92 (0.89–0.95) whereas AUROC for LACD was 0.94 (0.92–0.97). Using conventional cutoff points, sensitivity/specificity was 93.0%/70.8% for SPAC and 94.1%/87.5% for LACD. Sequential testing using both SPAC and LACD increased the specificity to 94.4% and decreased the sensitivity to 87.0%. Conclusion SPAC has significantly lower specificity than LACD measurement using conventional cutoffs but interpretation of the findings can be performed by modestly trained personnel. PMID:21997356

Isolated cardiophrenic angle node metastasis from ovarian primary. report of two cases

PubMed Central

2011-01-01

Ovarian cancer is the most lethal gynaecologic malignancy. It usually spreads out of the abdomen involving thoraco-abdominal organs and serosal surface. This disease is poorly curable and surgery, at early stage, is supposed to achieve the best survival outcome. In systemic dissemination, chemiotherapy is indicated, sometimes with neoadjuvant aim. The most common clinical expressions of advanced ovarian carcinoma are multiple adenopathy, neoplastic pleuritis, peritoneal seeding and distant metastasis, mainly hepatic and pulmonary. Isolated adenopathy of the mediastinum is rare and isolated bilateral have never been described before. We report two cases of isolated bilateral cardiophrenic angle lymphnode metastasis from ovarian carcinoma, without peritoneal and pleural involvement. Both patients were successfully resected through minimally invasive thoracic surgery. About the role of surgery, few data are available but survival seems to be longer after resection thus, more investigation is required to make the indication to surgery more appropriate in advanced cases. PMID:21208441

Evaluation of the anterior chamber angle in Asian Indian eyes by ultrasound biomicroscopy and gonioscopy.

PubMed

Kaushik, Sushmita; Jain, Rajeev; Pandav, Surinder Singh; Gupta, Amod

2006-09-01

To compare the ultrasound biomicroscopic measurement of the anterior chamber angle in Asian Indian eyes, with the angle width estimated by gonioscopy. Patients with open and closed angles attending a glaucoma clinic were recruited for the study. Temporal quadrants of the angles of patients were categorized by gonioscopy as Grade 0 to Grade 4, using Shaffer's classification. These angles were quantified by ultrasound biomicroscopy (UBM) using the following biometric characteristics: Angle opening distance at 250 micro (AOD 250) and 500 micro (AOD 500) from the scleral spur and trabecular meshwork-ciliary process distance (TCPD). The angles were further segregated as "narrow angles" (Schaffer's Grade 2 or less) and "open angles" (Schaffer's Grade 3 and 4). The UBM measurements were computed in each case and analyzed in relation to the gonioscopic angle evaluation. One hundred and sixty three eyes of 163 patients were analyzed. One hundred and six eyes had "narrow angles" and 57 eyes had "open angles" on gonioscopy. There was a significant difference among the mean UBM measurements of each angle grade estimated by gonioscopy (P < 0.001). The Pearson correlation coefficient between all UBM parameters and gonioscopy grades was significant at the 0.01 level. The mean AOD 250, AOD 500 and TCPD in narrow angles were 58+/-49 micro, 102+/-84 micro and 653+/-124 respectively, while it was 176+/-47 micro, 291+/-62 micro and 883+/-94 micro in eyes with open angles (P < 0.001) respectively. The angle width estimated by gonioscopy correlated significantly with the angle dimensions measured by UBM. Gonioscopy, though a subjective test, is a reliable method for estimation of the angle width.

Improvement of maneuver aerodynamics by spanwise blowing

NASA Technical Reports Server (NTRS)

Erickson, G. E.; Campbell, J. F.

1977-01-01

Spanwise blowing was used to test a generalized wind-tunnel model to investigate component concepts in order to provide improved maneuver characteristics for advanced fighter aircraft. Primary emphasis was placed on performance, stability, and control at high angles of attack and subsonic speeds. Test data were obtained in the Langley high speed 7 by 10 foot tunnel at free stream Mach numbers up to 0.50 for a range of model angles of attack, jet momentum coefficients, and leading and trailing edge flap deflection angles. Spanwise blowing on a 44 deg swept trapezoidal wing resulted in leading edge vortex enhancement with subsequent large vortex induced lift increments and drag polar improvements at the higher angles of attack. Small deflections of a leading edge flap delayed these lift and drag benefits to higher angles of attack. In addition, blowing was more effective at higher Mach numbers. Spanwise blowing in conjunction with a deflected trailing edge flap resulted in lift and drag benefits that exceeded the summation of the effects of each high lift device acting alone. Asymmetric blowing was an effective lateral control device at the higher angles of attack.

Progress report on understanding AFIS seed coat nep levels in pre-opened slivers on the Advanced Fiber Information System (AFIS)

USDA-ARS?s Scientific Manuscript database

The Advanced Fiber Information System (AFIS) is utilized in this segment of the research project to study how seed coat neps are measured. A patent search was conducted, and studied to assist with the understanding of the AFIS measurement of this impurity in raw cotton. The older AFIS 2 is primari...

[Fe II] emissions associated with the young interacting binary UY Aurigae

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pyo, Tae-Soo; Hayashi, Masahiko; Beck, Tracy L.

We present high-resolution 1.06-1.28 μm spectra toward the interacting binary UY Aur obtained with GEMINI/NIFS and the adaptive optics system Altair. We have detected [Fe II] λ1.257 μm and He I λ1.083 μm lines from both UY Aur A (the primary source) and UY Aur B (the secondary). In [Fe II] UY Aur A drives fast and widely opening outflows with an opening angle of ∼90° along a position angle of ∼40°, while UY Aur B is associated with a redshifted knot. The blueshifted and redshifted emissions show a complicated structure between the primary and secondary. The radial velocities ofmore » the [Fe II] emission features are similar for UY Aur A and B: ∼ –100 km s{sup –1} for the blueshifted emission and ∼ +130 km s{sup –1} for the redshifted component. The He I line profile observed toward UY Aur A comprises a central emission feature with deep absorptions at both blueshifted and redshifted velocities. These absorption features may be explained by stellar wind models. The He I line profile of UY Aur B shows only an emission feature.« less

Structural brain alterations in primary open angle glaucoma: a 3T MRI study

PubMed Central

Wang, Jieqiong; Li, Ting; Sabel, Bernhard A.; Chen, Zhiqiang; Wen, Hongwei; Li, Jianhong; Xie, Xiaobin; Yang, Diya; Chen, Weiwei; Wang, Ningli; Xian, Junfang; He, Huiguang

2016-01-01

Glaucoma is not only an eye disease but is also associated with degeneration of brain structures. We now investigated the pattern of visual and non-visual brain structural changes in 25 primary open angle glaucoma (POAG) patients and 25 age-gender-matched normal controls using T1-weighted imaging. MRI images were subjected to volume-based analysis (VBA) and surface-based analysis (SBA) in the whole brain as well as ROI-based analysis of the lateral geniculate nucleus (LGN), visual cortex (V1/2), amygdala and hippocampus. While VBA showed no significant differences in the gray matter volumes of patients, SBA revealed significantly reduced cortical thickness in the right frontal pole and ROI-based analysis volume shrinkage in LGN bilaterally, right V1 and left amygdala. Structural abnormalities were correlated with clinical parameters in a subset of the patients revealing that the left LGN volume was negatively correlated with bilateral cup-to-disk ratio (CDR), the right LGN volume was positively correlated with the mean deviation of the right visual hemifield, and the right V1 cortical thickness was negatively correlated with the right CDR in glaucoma. These results demonstrate that POAG affects both vision-related structures and non-visual cortical regions. Moreover, alterations of the brain visual structures reflect the clinical severity of glaucoma. PMID:26743811

Evidence-based practice guideline of Chinese herbal medicine for primary open-angle glaucoma (qingfeng -neizhang).

PubMed

Yang, Yingxin; Ma, Qiu-Yan; Yang, Yue; He, Yu-Peng; Ma, Chao-Ting; Li, Qiang; Jin, Ming; Chen, Wei

2018-03-01

Primary open angle glaucoma (POAG) is a chronic, progressive optic neuropathy. The aim was to develop an evidence-based clinical practice guideline of Chinese herbal medicine (CHM) for POAG with focus on Chinese medicine pattern differentiation and treatment as well as approved herbal proprietary medicine. The guideline development group involved in various pieces of expertise in contents and methods. Authors searched electronic databases include CNKI, VIP, Sino-Med, Wanfang data, PubMed, the Cochrane Library, EMBASE, as well as checked China State Food and Drug Administration (SFDA) from the inception of these databases to June 30, 2015. Systematic reviews and randomized controlled trials of Chinese herbal medicine treating adults with POAG were evaluated. Risk of bias tool in the Cochrane Handbook and evidence strength developed by the GRADE group were applied for the evaluation, and recommendations were based on the findings incorporating evidence strength. After several rounds of Expert consensus, the final guideline was endorsed by relevant professional committees. CHM treatment principle and formulae based on pattern differentiation together with approved patent herbal medicines are the main treatments for POAG, and the diagnosis and treatment focusing on blood related patterns is the major domain. CHM therapy alone or combined with other conventional treatment reported in clinical studies together with Expert consensus were recommended for clinical practice.

Linkage to 10q22 for maximum intraocular pressure and 1p32 for maximum cup-to-disc ratio in an extended primary open-angle glaucoma pedigree.

PubMed

Charlesworth, Jac C; Dyer, Thomas D; Stankovich, Jim M; Blangero, John; Mackey, David A; Craig, Jamie E; Green, Catherine M; Foote, Simon J; Baird, Paul N; Sale, Michèle M

2005-10-01

The purpose of this study was to identify genetic contributions to primary open-angle glaucoma (POAG) through investigations of two quantitative components of the POAG phenotype. Genome-wide multipoint variance-components linkage analyses of maximum recorded intraocular pressure (IOP) and maximum vertical cup-to-disc ratio were conducted on data from a single, large Australian POAG pedigree that has been found to segregate the myocilin Q368X mutation in some individuals. Multipoint linkage analysis of maximum recorded IOP produced a peak LOD score of 3.3 (P = 0.00015) near marker D10S537 on 10q22, whereas the maximum cup-to-disc ratio produced a peak LOD score of 2.3 (P = 0.00056) near markers D1S197 to D1S220 on 1p32. Inclusion of the myocilin Q368X mutation as a covariate provided evidence of an interaction between this mutation and the IOP and cup-to-disc ratio loci. Significant linkage has been identified for maximum IOP and suggestive linkage for vertical cup-to-disc ratio. Identification of genes contributing to the variance of these traits will enhance understanding of the pathophysiology of POAG as a whole.

Mediterranean diet adherence by patients with primary open angle glaucoma.

PubMed

Abreu-Reyes, J A; Álvarez-Luis, D; Arteaga-Hernández, V; Sánchez-Mendez, M; Abreu-González, R

2017-08-01

To study the adherence to the Mediterranean diet in patients affected by primary open angle glaucoma (POAG). An observational study was conducted to assess the adherence to the Mediterranean diet in patients affected by POAG, and who attended the Ophthalmology Department of the Canary Islands University Hospital. The study included completing a 14-item questionnaire validated by the PREDIMED Study, in person or by telephone. A total of 100 questionnaires were completed successfully by 50 males and 50 females. The mean age was 69.58 years for the males and 67.42 years for women. The men had more comorbidities than women (tobacco 14 vs. 3%), arterial hypertension, and diabetes (30 vs. 28%, and 16 vs. 6%, respectively). Adherence to the Mediterranean diet in males, was low in 9 patients (18%), moderate in 37 (74%), and high in 4 (8%) cases. In women adherence was low in 14 patients (28%), moderate in 34 (68%), and high in 2 (6%) cases. The overall adhesion to the Mediterranean diet is low in 23%, moderate in 71% and high in 6% of the cases. Patients who are affected by POAG have moderate adherence to the Mediterranean diet. Copyright © 2017 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

Relationship between blood pressure and retrobulbar blood flow in dipper and nondipper primary open-angle glaucoma patients.

PubMed

Marjanović, Ivan; Marjanović, Marija; Martinez, Antonio; Marković, Vujica; Božić, Marija; Stojanov, Vesna

2016-11-04

To evaluate the relationship between retrobulbar hemodynamic parameters in the ophthalmic artery (OA), central retinal artery, and short posterior ciliary artery and 24-hour blood pressure (BP) measurements in dipper and nondipper patients with primary open-angle glaucoma (POAG). A prospective, cross-sectional, and observational study was conducted on consecutive patients, referred or recruited, attending the outpatient service of our ophthalmology department. Ambulatory BP monitoring, Doppler imaging, and ocular pulse amplitude measurements were performed on the same day. Patients with nocturnal BP decrease up to 10% of the diurnal BP were defined as dippers and those with BP decrease less than 10% were defined as nondippers. A total of 114 patients (36 nondippers and 78 dippers) were included in the study. The end-diastolic velocity was significantly lower and the resistivity index (RI) was significantly higher in the dippers than in the nondippers (p<0.0001 and p<0.0001, respectively). The RI in the OA was significantly correlated with daytime and nighttime systolic BP and with the daytime mean arterial pressure in the dippers. The RI in the OA significantly correlates with BP in patients with POAG with nocturnal BP dips. Additionally, retrobulbar blood flow parameters are reduced in dippers as compared with nondippers with POAG.

Evaluation of retinal ganglion cell function after intraocular pressure reduction measured by pattern electroretinogram in patients with primary open-angle glaucoma.

PubMed

Karaśkiewicz, Joanna; Penkala, Krzysztof; Mularczyk, Maciej; Lubiński, Wojciech

2017-04-01

To evaluate retinal ganglion cell (RGC) function after intraocular pressure (IOP) reduction measured by pattern electroretinogram (PERG) in patients with newly diagnosed, non-treated preperimetric and early stages of primary open-angle glaucoma (POAG). Twenty-four eyes from 24 patients with POAG: 11 eyes with preperimetric glaucoma and 13 eyes with early glaucoma received Ganfort ® (bimatoprost + timolol) once a day for a period of 1 month. Before and after the treatment, following measurements were analyzed: IOP, mean ocular perfusion pressure (MOPP), peak time of P50 and amplitude of P50 and N95 waves in PERG (ISCEV standard 2012). Correlations between PERG P50 and N95 waves, IOP and MOPP were calculated. After therapy, IOP significantly decreased in all eyes, on average 31%. Significant increase in MOPP in all eyes on average 14% was detected. PERG amplitude of P50 and N95 waves increased in 75 and 79% eyes, respectively, on average P50 by 28% and N95 by 38%. There were no significant interactions between the change of PERG parameters in time and stage of glaucoma. Significant IOP-lowering therapy can improve RGC function measured by PERG, in patients with preperimetric and early stages of POAG.

When Is Evidence Enough Evidence? A Systematic Review and Meta-Analysis of the Trabectome as a Solo Procedure in Patients with Primary Open-Angle Glaucoma

PubMed Central

Chow, Jeffrey T. Y.; Hutnik, Cindy M. L.; Solo, Karla

2017-01-01

The purpose of this systematic review and meta-analysis was to examine the availability of evidence for one of the earliest available minimally invasive glaucoma surgery (MIGS) procedures, the Trabectome. Various databases were searched up to December 20, 2016, for any published studies assessing the use of the Trabectome as a solo procedure in patients with primary open-angle glaucoma (POAG). The standardized mean differences (SMD) were calculated for the change in intraocular pressure (IOP) and number of glaucoma mediations used at 1-month, 6-month, and 12-month follow-up. After screening, three studies and one abstract with analyzable data were included. The meta-analysis showed statistically significant reductions in IOP and number of glaucoma medications used at all time points. Though the Trabectome as a solo procedure appears to lower IOP and reduces the number of glaucoma medications, more high-quality studies are required to make definitive conclusions. The difficulty of obtaining evidence may be one of the many obstacles that limit a full understanding of the potential safety and/or efficacy benefits compared to standard treatments. The time has come for a thoughtful and integrated approach with stakeholders to determine optimal access to care strategies for our patients. PMID:28740733

When Is Evidence Enough Evidence? A Systematic Review and Meta-Analysis of the Trabectome as a Solo Procedure in Patients with Primary Open-Angle Glaucoma.

PubMed

Chow, Jeffrey T Y; Hutnik, Cindy M L; Solo, Karla; Malvankar-Mehta, Monali S

2017-01-01

The purpose of this systematic review and meta-analysis was to examine the availability of evidence for one of the earliest available minimally invasive glaucoma surgery (MIGS) procedures, the Trabectome. Various databases were searched up to December 20, 2016, for any published studies assessing the use of the Trabectome as a solo procedure in patients with primary open-angle glaucoma (POAG). The standardized mean differences (SMD) were calculated for the change in intraocular pressure (IOP) and number of glaucoma mediations used at 1-month, 6-month, and 12-month follow-up. After screening, three studies and one abstract with analyzable data were included. The meta-analysis showed statistically significant reductions in IOP and number of glaucoma medications used at all time points. Though the Trabectome as a solo procedure appears to lower IOP and reduces the number of glaucoma medications, more high-quality studies are required to make definitive conclusions. The difficulty of obtaining evidence may be one of the many obstacles that limit a full understanding of the potential safety and/or efficacy benefits compared to standard treatments. The time has come for a thoughtful and integrated approach with stakeholders to determine optimal access to care strategies for our patients.

Neural tube defects – recent advances, unsolved questions and controversies

PubMed Central

Copp, Andrew J.; Stanier, Philip; Greene, Nicholas D. E.

2014-01-01

Neural tube defects (NTDs) are severe congenital malformations affecting around 1 in every 1000 pregnancies. Here we review recent advances and currently unsolved issues in the NTD field. An innovation in clinical management has come from the demonstration that closure of open spina bifida lesions in utero can diminish neurological dysfunction in children. Primary prevention by folic acid has been enhanced through introduction of mandatory food fortification in some countries, although not yet in UK. Genetic predisposition comprises the majority of NTD risk, and genes that regulate folate one-carbon metabolism and planar cell polarity have been strongly implicated. The sequence of human neural tube closure events remains controversial, but study of mouse NTD models shows that anencephaly, open spina bifida and craniorachischisis result from failure of primary neurulation, while skin-covered spinal dysraphism results from defective secondary neurulation. Other ‘NTD’ malformations, such as encephalocele, are likely to be post-neurulation disorders. PMID:23790957

[Computer-assisted multimedia interactive learning program "Primary Open-Angle Glaucoma"].

PubMed

Dick, V B; Zenz, H; Eisenmann, D; Tekaat, C J; Wagner, R; Jacobi, K W

1996-05-01

Advances in the area of information technology have opened up new possibilities for the use of interactive media in the training of medical students. Classical instructional technologies, such as video, slides, audio cassettes and computer programs with a textbook orientation, have been merged into one multimedia computer system. The medical profession has been increasingly integrating computer-based applications which can be used, for example, for record keeping within a medical practice. The goal of this development is to provide access to all modes of information storage and retrieval as well as documentation and training systems within a specific context. Since the beginning of the winter semester 1995, the Department of Ophthalmology in Giessen has used the learning program "Primary Open Angle Glaucoma" in student instruction. One factor that contributed to the implementation of this project was that actual training using patients within the clinic is difficult to conduct. Media-supported training that can provide a simulation of actual practice offers a suitable substitute. The learning program has been installed on Power PCs (Apple MacIntosh), which make up the technical foundation of our system. The program was developed using Hypercard software, which provides userfriendly graphical work environment. This controls the input and retrieval of data, direct editing of documents, immediate simulation, the creation of on-screen documents and the integration of slides that have been scanned in as well as QuickTime films. All of this can be accomplished without any special knowledge of programming language or operating systems on the part of the user. The glaucoma learning program is structured along the lines of anatomy, including an explanation of the circulation of the aqueous humor, pathology, clinical symptoms and findings, diagnosis and treatment. This structure along with the possibility for creating a list of personal files for the user with a collection of illustrations and text allows for quick access to learning content. The program is designed in such a way that working with and through it is done in a manner conducive to learning. Student response to the learning program as an accompaniment to instruction has been positive. Independent, supplemental student learning by means of an interactive learning program has raised the quality of study within the sciences. The use of a pedagogically sound multimedia program, that is oriented toward problem solving and based on actual cases offers students the opportunity to actively work ophthalmological material. An additional benefit is the development of competence in working with computer-support information systems, something that is playing an ever-increasing role within the medical profession.

Influence of several factors on ignition lag in a compression-ignition engine

NASA Technical Reports Server (NTRS)

Gerrish, Harold C; Voss, Fred

1932-01-01

This investigation was made to determine the influence of fuel quality, injection advance angle, injection valve-opening pressure, inlet-air pressure, compression ratio, and engine speed on the time lag of auto-ignition of a Diesel fuel oil in a single-cylinder compression-ignition engine as obtained from an analysis of indicator diagrams. Three cam-operated fuel-injection pumps, two pumps cams, and an automatic injection valve with two different nozzles were used. Ignition lag was considered to be the interval between the start of injection of the fuel as determined with a Stroborama and the start of effective combustion as determined from the indicator diagram, the latter being the point where 4.0 x 10(exp-6) pound of fuel had been effectively burned. For this particular engine and fuel it was found that: (1) for a constant start and the same rate of fuel injection up the point of cut-off, a variation in fuel quantity from 1.2 x 10(exp-4) to 4.1 x 10(exp-4) pound per cycle has no appreciable effect on the ignition lag; (2) injection advance angle increases or decreases the lag according to whether density, temperature, or turbulence has the controlling influence; (3) increase in valve-opening pressure slightly increases the lag; and (4) increase of inlet-air pressure, compression ratio, and engine speed reduces the lag.

Prevalence of comorbid retinal disease in patients with glaucoma at an academic medical center.

PubMed

Griffith, Joseph F; Goldberg, Jeffrey L

2015-01-01

Patients with various retinal diseases and patients who have undergone retinal procedures and surgeries have an increased risk of developing ocular hypertension and glaucoma. Little is known about the epidemiology of comorbid retinal diseases in glaucoma patients. This study evaluated the prevalence of retinal comorbidities in a population of patients with five types of glaucoma. A longitudinal, retrospective study was conducted using International Classification of Disease (ICD-9) billing records from 2003 to 2010 at an academic medical center. Patients were classified as having primary open-angle glaucoma (POAG), low tension open-angle glaucoma (NTG), pigmentary open-angle glaucoma, chronic-angle closure glaucoma (CACG), or pseudoexfoliation glaucoma (PXG) if they had at least three clinic visits with the same ICD-9 code. Patients were classified as having a retinal comorbidity if they had two visits with the same code. Variables were analyzed with the independent t-test, χ (2) test, analysis of variance, or Fisher's exact test. A total of 5,154 patients had glaucoma, and 14.8% of these had a retinal comorbidity. The prevalence of comorbid retinal disease was higher in patients with POAG (15.7%) than in those with NTG (10.7%), PXG (10.1%), or pigmentary open-angle glaucoma (3.7%; P<0.05). Two hundred and two patients had diabetic retinopathy, with POAG patients (4.5%) having a higher prevalence than those with CACG (1.4%) or PXG (0.6%; P<0.001). There were 297 patients who had macular degeneration and both POAG (2.0%) and PXG patients (2.9%) had a higher prevalence of nonexudative macular degeneration than those with CACG (0%; P<0.01). Patients with comorbid retinal disease had a higher prevalence of blindness and low vision than those without comorbid retinal disease (1.97% versus 1.02%, P=0.02). The high prevalence of comorbid retinal disease and the nearly twofold increase in blindness and low vision in this population demonstrate the need for ophthalmologists to determine if patients have multiple etiologies for their vision loss. The higher prevalence of certain retinal diseases in POAG patients may reflect common pathophysiological processes that warrant further investigation.

Glaucoma filtration surgery following sustained elevation of intraocular pressure secondary to intravitreal anti-VEGF injections.

PubMed

Skalicky, Simon E; Ho, Ivan; Agar, Ashish; Bank, Allan

2012-07-01

To document cases of sustained elevation of intraocular pressure (IOP) while receiving intravitreal anti-vascular endothelial growth factor (VEGF) agents and subsequent management. A retrospective series of all cases managed by the authors and colleagues was performed. Six patients developed sustained elevated IOP; five received ranibizumab and one bevacizumab. Four received unilateral and two received bilateral injections. Two had preexisting primary open-angle glaucoma and one had pseudoexfoliative glaucoma, all with stable IOP prior to anti-VEGF treatment. Angles were open in all cases. Peak IOP averaged 43 mm Hg (range: 34 to 60 mm Hg). The mean number of injections preceding the IOP increase was 10 (range: 1 to 20). Four patients required trabeculectomy, one selective laser trabeculoplasty, and one multiple topical medications. A sustained increase in IOP requiring glaucoma filtering surgery is a rare but important treatment complication for patients receiving intravitreal anti-VEGF therapy, especially those with preexisting glaucoma or glaucoma risk factors. Copyright 2012, SLACK Incorporated.

Safety and effectiveness of primary transscleral diode laser cyclophotoablation for glaucoma in Nigeria.

PubMed

Abdull, Mohammed M; Broadway, David C; Evans, Jennifer; Kyari, Fatima; Muazu, Fatima; Gilbert, Clare

2018-05-28

To investigate the safety, effectiveness and follow up rates after transscleral diode laser cyclophotocoagulation as primary treatment for seeing eyes with primary open angle glaucoma in Bauchi, Nigeria. There is a high prevalence of primary open angle glaucoma in Africa where adherence to medical treatment and acceptance of surgery are poor. Prospective case series PARTICIPANTS: New glaucoma patients where surgical intervention was recommended. A diode 810nm laser G-probe was used under retrobulbar anaesthesia to deliver approximately 20 shots for 2000ms, titrating the power. If both eyes were treated the first was the study eye. Repeat treatment offered if the intraocular pressure (IOP) was >21mmHg on two consecutive visits. Intraocular pressure <22mmHg, change in ≥2 lines of Snellen visual acuity, and complications. 201/204 eyes with complete data analysed. Mean age 52 years, 17 (8.3%) eyes were re-treated. Mean pre-treatment IOP was 39 (SD 11) mmHg. 106 (53%) attended at 12 months when the mean IOP was 19 (7-45) mmHg; 77 (73%) had IOP <22mmHg. Visual acuities were better in 13 (12.3%) and worse in 23 (21.7%) eyes. Post-operative complications included mild uveitis (5.5%), corneal oedema (2.5%), severe uveitis (0.5%) and transient hypotony (2.0%). No hypotony at 12 months. Transscleral diode laser cyclophotocoagulation controlled IOP in almost three quarters of eyes at 12 months with short-term preservation of vision and minimal complications. Poor follow-up in this setting highlights the need for an effective, safe and acceptable treatment where regular follow-up is less critical. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Laparoscopic versus open 1-stage resection of synchronous liver metastases and primary colorectal cancer

PubMed Central

Yazici, Pinar; Onder, Akin; Benlice, Cigdem; Yigitbas, Hakan; Kahramangil, Bora; Tasci, Yunus; Aksoy, Erol; Aucejo, Federico; Quintini, Cristiano; Miller, Charles; Berber, Eren

2017-01-01

Background The aim of this study is to compare the perioperative and oncologic outcomes of open and laparoscopic approaches for concomitant resection of synchronous colorectal cancer and liver metastases. Methods Between 2006 and 2015, all patients undergoing combined resection of primary colorectal cancer and liver metastases were included in the study (n=43). Laparoscopic and open groups were compared regarding clinical, perioperative and oncologic outcomes. Results There were 29 patients in the open group and 14 patients in the laparoscopic group. The groups were similar regarding demographics, comorbidities, histopathological characteristics of the primary tumor and liver metastases. Postoperative complication rate (44.8% vs. 7.1%, P=0.016) was higher, and hospital stay (10 vs. 6.4 days, P=0.001) longer in the open compared to the laparoscopic group. Overall survival (OS) was comparable between the groups (P=0.10); whereas, disease-free survival (DFS) was longer in laparoscopic group (P=0.02). Conclusions According to the results, in patients, whose primary colorectal cancer and metastatic liver disease was amenable to a minimally invasive resection, a concomitant laparoscopic approach resulted in less morbidity without compromising oncologic outcomes. This suggests that a laparoscopic approach may be considered in appropriate patients by surgeons with experience in both advanced laparoscopic liver and colorectal techniques. PMID:28861371

Laparoscopic versus open 1-stage resection of synchronous liver metastases and primary colorectal cancer.

PubMed

Gorgun, Emre; Yazici, Pinar; Onder, Akin; Benlice, Cigdem; Yigitbas, Hakan; Kahramangil, Bora; Tasci, Yunus; Aksoy, Erol; Aucejo, Federico; Quintini, Cristiano; Miller, Charles; Berber, Eren

2017-08-01

The aim of this study is to compare the perioperative and oncologic outcomes of open and laparoscopic approaches for concomitant resection of synchronous colorectal cancer and liver metastases. Between 2006 and 2015, all patients undergoing combined resection of primary colorectal cancer and liver metastases were included in the study (n=43). Laparoscopic and open groups were compared regarding clinical, perioperative and oncologic outcomes. There were 29 patients in the open group and 14 patients in the laparoscopic group. The groups were similar regarding demographics, comorbidities, histopathological characteristics of the primary tumor and liver metastases. Postoperative complication rate (44.8% vs . 7.1%, P=0.016) was higher, and hospital stay (10 vs . 6.4 days, P=0.001) longer in the open compared to the laparoscopic group. Overall survival (OS) was comparable between the groups (P=0.10); whereas, disease-free survival (DFS) was longer in laparoscopic group (P=0.02). According to the results, in patients, whose primary colorectal cancer and metastatic liver disease was amenable to a minimally invasive resection, a concomitant laparoscopic approach resulted in less morbidity without compromising oncologic outcomes. This suggests that a laparoscopic approach may be considered in appropriate patients by surgeons with experience in both advanced laparoscopic liver and colorectal techniques.

The influence of third molars in the line of mandibular angle fractures on wound and bone healing.

PubMed

Ulbrich, N; Ettl, T; Waiss, W; Gosau, M; Moralis, A; Reichert, T E; Mueller, S

2016-07-01

The objective of this study was to evaluate postoperative complications after removal or retention of the third molar in the line of mandibular angle fractures. This retrospective study included the data of 98 patients with a molar in the line of a mandibular angle fracture treated with internal reduction and mini-plate fixation at our department over 9 years. Patients were classified into two groups: tooth removal during osteosynthesis (n = 45) and tooth retention (n = 55). The primary target criterion was the incidence of minor (outpatient treatment, local measures) and major (surgical revision, rehospitalisation) complications. Time between trauma and surgery was 1.4 days (range 0 to 12), and the average follow-up 291 days (range 66 to 863). Regarding the eruption status, 26 of 52 (50.0 %) impacted third molars, 11 of 19 (57.9 %) incompletely erupted and 8 of 27 (29.6 %) completely erupted molars had been removed during open reduction. Overall, 17 (17.3 %) patients had postoperative minor (n = 7) or major (n = 10) complications, in detail 10/45 (22.0 %) patients after tooth removal and 7/55 (13 %) patients after tooth retention (p = 0.286). Complication rates between impacted and incompletely erupted third molars (impacted molars 15.0 %, incompletely erupted molars 10.0 %) did not differ significantly, but completely erupted molars had a complication rate of 26.0 %. Mandibular angle fractures with a completely erupted third molar show the highest complication rate after open reduction and osteosynthesis. Retention of a non-infectious third molar facilitates open reduction and does not increase the complication risk. The study helps with the decision of removing or retention of a third molar during surgical treatment of a mandibular angle fracture.

On the evolution of jet energy and opening angle in strongly coupled plasma

NASA Astrophysics Data System (ADS)

Chesler, Paul M.; Rajagopal, Krishna

2016-05-01

We calculate how the energy and the opening angle of jets in {N} = 4 SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet /dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet /dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say the opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that {N} = 4 SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the {N} = 4 SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. We close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.

On the evolution of jet energy and opening angle in strongly coupled plasma

DOE PAGES

Chesler, Paul M.; Rajagopal, Krishna

2016-05-17

We calculate how the energy and the opening angle of jets in N = 4SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet/dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet/dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say themore » opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N = 4SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N = 4SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. In conclusion, we close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.« less

Effect of contact angle on the orientation, stability, and assembly of dense floating cubes.

PubMed

Daniello, Robert; Khan, Kashan; Donnell, Michael; Rothstein, Jonathan P

2014-02-01

In this paper, the effect of contact angle, density, and size on the orientation, stability, and assembly of floating cubes was investigated. All the cubes tested were more dense than water. Floatation occurred as a result of capillary stresses induced by deformation of the air-water interface. The advancing contact angle of the bare acrylic cubes was measured to be 85°. The contact angle of the cubes was increased by painting the cubes with a commercially available superhydrophobic paint to reach an advancing contact angle of 150°. Depending on their size, density, and contact angle, the cubes were observed to float in one of three primary orientations: edge up, vertex up, and face up. An experimental apparatus was built such that the sum of the gravitational force, buoyancy force, and capillary forces could be measured using a force transducer as a function of cube position as it was lowered through the air-water interface. Measurements showed that the maximum capillary forces were always experienced for the face up orientation. However, when floatation was possible in the vertex up orientation, it was found to be the most stable cube orientation because it had the lowest center of gravity. A series of theoretical predictions were performed for the cubes floating in each of the three primary orientations to calculate the net force on the cube. The theoretical predictions were found to match the experimental measurements well. A cube stability diagram of cube orientation as a function of cube contact angle and size was prepared from the predictions of theory and found to match the experimental observations quite well. The assembly of cubes floating face up and vertex up were also studied for assemblies of two, three, and many cubes. Cubes floating face up were found to assemble face-to-face and form regular square lattice patterns with no free interface between cubes. Cubes floating vertex up were found to assemble in a variety of different arrangements including edge-to-edge, vertex-to-vertex, face-to-face, and vertex-to-face with the most probably assembly being edge-to-edge. Large numbers of vertex up cubes were found to pack with a distribution of orientations and alignments.

Cost-effectiveness of community screening for glaucoma in rural India: a decision analytical model.

PubMed

John, D; Parikh, R

2018-02-01

Studies in several countries have demonstrated the cost-effectiveness of population-based screening for glaucoma when targeted at high-risk groups such as older adults and with familial history of disease. This study conducts a cost-effective analysis of a hypothetical community screening and subsequent treatment programme in comparison to opportunistic case finding for glaucoma in rural India. A hypothetical screening programme for both primary open-angle glaucoma and angle-closure disease was built for a population aged between 40 and 69 years in rural areas of India. A decision analytical model was built to model events, costs and treatment pathways with and without a hypothetical screening programme for glaucoma for a rural-based population aged between 40 and 69 years in India. The treatment pathway included both primary open-angle glaucoma and angle-closure disease. The data on costs of screening and treatment were provided by an administrator of a tertiary eye hospital in Eastern India. The probabilities for the screening and treatment pathway were derived from published literature and a glaucoma specialist. The glaucoma prevalence rates were adapted from the Chennai Glaucoma Study findings. An incremental cost-effectiveness ratio value of ₹7292.30 per quality-adjusted life-year was calculated for a community-screening programme for glaucoma in rural India. The community screening for glaucoma would treat an additional 2872 cases and prevent 2190 person-years of blindness over a 10-year period. Community screening for glaucoma in rural India appears to be cost-effective when judged by a ratio of willingness-to-pay thresholds as per WHO-CHOICE guidelines. For community screening to be cost-effective, adequate resources, such as trained medical personnel and equipment would need to be made available. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Anterior segment parameters as predictors of intraocular pressure reduction after phacoemulsification in eyes with open-angle glaucoma.

PubMed

Hsia, Yen C; Moghimi, Sasan; Coh, Paul; Chen, Rebecca; Masis, Marisse; Lin, Shan C

2017-07-01

To evaluate intraocular pressure (IOP) change after cataract surgery in eyes with open-angle glaucoma (OAG) and its relationship to angle and anterior segment parameters measured by anterior segment optical coherence tomography (AS-OCT). University of California, San Francisco, California, USA. Prospective case series. Eyes were placed into a narrow-angle group or open-angle group based on gonioscopy grading. Biometric parameters were measured using AS-OCT (Visante) preoperatively, and IOP 4 months after surgery was obtained. The IOP change and its relationship to AS-OCT parameters were evaluated. Eighty-one eyes of 69 patients were enrolled. The mean age of the patients was 76.8 years. The preoperative IOP was 15.02 mm Hg on 1.89 glaucoma medications. The average mean deviation of preoperative visual field was -4.58 dB. The mean IOP reduction was 2.1 mm Hg (12.8%) from a preoperative mean of 15.0 mm Hg. The IOP reduction was significantly greater in eyes with narrow angles than in eyes with open angles (20.4% versus 8.0%) (P = .002). In multivariate analysis, preoperative IOP (β = -0.53, P < .001, R 2  = 0.40), angle-opening distance at 500 mm (β = 5.83, P = .02, R 2  = 0.45), angle-opening distance at 750 mm (β = 5.82, P = .001, R 2  = 0.52), and lens vault (β = -0.002, P = .009, R 2  = 0.47) were associated with IOP reduction postoperatively. In eyes with OAG, IOP reduction after cataract surgery was greater in eyes with narrower angles. Preoperative IOP, angle-opening distance, and lens vault were predictors for IOP reduction. Copyright © 2017 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

A Generalized Maxwell Model for Creep Behavior of Artery Opening Angle

PubMed Central

Zhang, W.; Guo, X.; Kassab, G. S.

2009-01-01

An artery ring springs open into a sector after a radial cut. The opening angle characterizes the residual strain in the unloaded state, which is fundamental to understanding stress and strain in the vessel wall. A recent study revealed that the opening angle decreases with time if the artery is cut from the loaded state, while it increases if the cut is made from the no-load state due to viscoelasticity. In both cases, the opening angle approaches the same value in 3 hours. This implies that the characteristic relaxation time is about 10,000 sec. Here, the creep function of a generalized Maxwell model (a spring in series with six Voigt bodies) is used to predict the temporal change of opening angle in multiple time scales. It is demonstrated that the theoretical model captures the salient features of the experimental results. The proposed creep function may be extended to study the viscoelastic response of blood vessels under various loading conditions. PMID:19045526

A flexible Monte Carlo tool for patient or phantom specific calculations: comparison with preliminary validation measurements

NASA Astrophysics Data System (ADS)

Davidson, S.; Cui, J.; Followill, D.; Ibbott, G.; Deasy, J.

2008-02-01

The Dose Planning Method (DPM) is one of several 'fast' Monte Carlo (MC) computer codes designed to produce an accurate dose calculation for advanced clinical applications. We have developed a flexible machine modeling process and validation tests for open-field and IMRT calculations. To complement the DPM code, a practical and versatile source model has been developed, whose parameters are derived from a standard set of planning system commissioning measurements. The primary photon spectrum and the spectrum resulting from the flattening filter are modeled by a Fatigue function, cut-off by a multiplying Fermi function, which effectively regularizes the difficult energy spectrum determination process. Commonly-used functions are applied to represent the off-axis softening, increasing primary fluence with increasing angle ('the horn effect'), and electron contamination. The patient dependent aspect of the MC dose calculation utilizes the multi-leaf collimator (MLC) leaf sequence file exported from the treatment planning system DICOM output, coupled with the source model, to derive the particle transport. This model has been commissioned for Varian 2100C 6 MV and 18 MV photon beams using percent depth dose, dose profiles, and output factors. A 3-D conformal plan and an IMRT plan delivered to an anthropomorphic thorax phantom were used to benchmark the model. The calculated results were compared to Pinnacle v7.6c results and measurements made using radiochromic film and thermoluminescent detectors (TLD).

Tonal noise of a controlled-diffusion airfoil at low angle of attack and Reynolds number.

PubMed

Padois, Thomas; Laffay, Paul; Idier, Alexandre; Moreau, Stéphane

2016-07-01

The acoustic signature of a controlled-diffusion airfoil immersed in a flow is experimentally characterized. Acoustic measurements have been carried out in an anechoic open-jet-wind-tunnel for low Reynolds numbers (from 5 × 10(4) to 4.3 × 10(5)) and several angles of attack. As with the NACA0012, the acoustic spectrum is dominated by discrete tones. These tonal behaviors are divided into three different regimes. The first one is characterized by a dominant primary tone which is steady over time, surrounded by secondary peaks. The second consists of two unsteady primary tones associated with secondary peaks and the third consists of a hump dominated by several small peaks. A wavelet study allows one to identify an amplitude modulation of the acoustic signal mainly for the unsteady tonal regime. This amplitude modulation is equal to the frequency interval between two successive tones. Finally, a bispectral analysis explains the presence of tones at higher frequencies.

Effect of primary iris and ciliary body cyst on anterior chamber angle in patients with shallow anterior chamber*

PubMed Central

Wang, Bing-hong; Yao, Yu-feng

2012-01-01

Objective: To evaluate the prevalence of primary iris and/or ciliary body cysts in eyes with shallow anterior chamber and their effect on the narrowing of the anterior chamber angle. Methods: Among the general physical check-up population, subjects with shallow anterior chambers, as judged by van Herick technique, were recruited for further investigation. Ultrasound biomicroscope (UBM) was used to detect and measure the cysts located in the iris and/or ciliary body, the anterior chamber depth (ACD), the angle opening distance at 500 μm (AOD500), and the trabecular-iris angle (TIA). A-scan ultrasonography was used to measure the ocular biometry, including lens thickness, axial length, lens/axial length factor (LAF), and relative lens position (RLP). The effect of the cyst on narrowing the corresponding anterior chamber angle and the entire angle was evaluated by the UBM images, ocular biometry, and gonioscopic grading. The eye with unilateral cyst was compared with the eye without the cyst for further analysis. Results: Among the 727 subjects with shallow anterior chamber, primary iris and ciliary body cysts were detected in 250 (34.4%) patients; among them 96 (38.4%) patients showed unilateral single cyst, 21 (8.4%) patients had unilateral double cysts, and 42 (16.8%) patients manifested unilateral multiple and multi-quadrants cysts. Plateau iris configuration was found in 140 of 361 (38.8%) eyes with cysts. The mean size of total cysts was (0.6547±0.2319) mm. In evaluation of the effect of the cyst size and location on narrowing the corresponding angle to their position, the proportion of the cysts causing corresponding angle narrowing or closure among the cysts larger than 0.8 mm (113/121, 93.4%) was found to be significantly higher than that of the cysts smaller than 0.8 mm (373/801, 46.6%), and a significant higher proportion was also found in the cysts located at iridociliary sulcus (354/437, 81.0%) than in that at the pars plicata (131/484, 27.1%). In evaluating the effect of the cyst on the entire anterior chamber angle, the eyes with multiple and multi-quadrants cysts manifested significant narrowing of the entire anterior chamber angle as compared with the eyes without cysts, based on the data analysis in comparison of TIA, AOD500, and gonioscopic grading evaluation. The unilateral single or double cysts in the eyes had no significant effect on narrowing of anterior chamber angle as compared with eyes without cysts. The iris and/or ciliary body cysts did not seem to affect the axial length, ACD, lens thickness, RLP, LAF. Conclusions: The prevalence of primary iris and ciliary body cyst was 34.4% in the subjects with shallow anterior chamber. The cysts larger than 0.8 mm, locating at iridociliary sulcus, or multiple and extensive cysts were inclined to cause the angle narrowing or closure. PMID:22949363

Augmentation of maneuver performance by spanwise blowing

NASA Technical Reports Server (NTRS)

Erickson, G. E.; Campbell, J. F.

1977-01-01

A generalized wind tunnel model was tested to investigate new component concepts utilizing spanwise blowing to provide improved maneuver characteristics for advanced fighter aircraft. Primary emphasis was placed on high angle of attack performance, stability, and control at subsonic speeds. Spanwise blowing on a 44 deg swept trapezoidal wing resulted in leading edge vortex enhancement with subsequent large vortex-induced lift increments and drag polar improvements at the higher angles of attack. Small deflections of a leading edge flap delayed these lift and drag benefits to higher angles of attack. In addition, blowing was more effective at higher Mach numbers. Spanwise blowing in conjunction with a deflected trailing edge flap resulted in lift and drag benefits that exceeded the summation of the effects of each high lift device acting alone. Asymmetric blowing was an effective lateral control device at the higher angles of attack. Spanwise blowing on the wing reduced horizontal tail loading and improved the lateral-directional stability characteristics of a wing-horizontal tail-vertical tail configuration.

A 4-week, dose-ranging study comparing the efficacy, safety and tolerability of latanoprost 75, 100 and 125 μg/mL to latanoprost 50 μg/mL (xalatan) in the treatment of primary open-angle glaucoma and ocular hypertension

PubMed Central

2012-01-01

Background Several studies have investigated the effect of latanoprost on intraocular pressure (IOP). We compared the IOP-lowering effects of three higher concentrations of latanoprost with the commercially available concentration of 0.005% (50 μg/mL) in patients with primary open-angle glaucoma or ocular hypertension. Methods Treatment-naive subjects or those receiving IOP-lowering medication with baseline IOP levels of ≥24 mmHg and ≤36 mmHg in at least one eye after washout were randomized to receive an evening dose of latanoprost 50, 75, 100, or 125 μg/mL for 4 weeks. At weeks 1, 2, 3, and 4, ocular examinations were performed and IOP was measured. Ocular symptoms and adverse events were monitored. The primary efficacy endpoint was the change in IOP from baseline to week 4 at 8 a.m. and 4 p.m. for the per protocol (PP) population using a "worse eye" analysis. Secondary efficacy endpoints were change in IOP at each time point from baseline across all visits, and percentage change in IOP from baseline to week 4 at 8 a.m. Results In all, 282 patients were randomized and treated; 274 were included in the PP population. Treatment groups were similar at baseline; 68% were diagnosed with primary open-angle glaucoma. Mean baseline IOP levels were comparable across treatments. There were no statistically significant differences in IOP reductions from baseline to week 4 at either time point between those treated with higher concentrations of latanoprost versus those receiving 50 μg/mL. Least squares mean IOP changes at 8 a.m. were −10.13, -9.59, -10.02, and −9.06 mmHg for latanoprost 50, 75, 100, and 125 μg/mL, respectively, and at 4 p.m. were −8.90, -8.29, -8.81, and −8.34 mmHg, respectively. Results of secondary efficacy analyses supported those of the primary analysis. Conjunctival hyperemia, the most commonly reported adverse event, occurred in 16.9%, 18.6%, 20.8% and 15.9% of subjects receiving latanoprost 50, 75, 100, and 125 μg/mL, respectively. Conclusions IOP reductions were observed in all treatment groups postbaseline, with no clinically relevant or statistically significant differences detected favoring any of the higher concentrations of latanoprost compared with latanoprost 50 μg/mL. All doses of latanoprost were well tolerated. Trial registration Clinical Trials.gov Identifier NCT01379144. PMID:22607109

Ethnic differences in primary angle-closure glaucoma.

PubMed

Yip, Jennifer L Y; Foster, Paul J

2006-04-01

Observational studies from different countries have shown that populations of East Asian origin have a higher frequency of primary angle-closure glaucoma compared with those of European or African descent. As half of all cases of glaucoma reside in Asia, and with primary angle-closure glaucoma carrying a higher rate of visual morbidity, primary angle-closure glaucoma poses an important public health problem; however, the inconsistent use of techniques and definitions to detect and diagnose primary angle-closure glaucoma has resulted in difficulties in interpreting the accuracy and comparability of such data. Therefore it is important to review these studies in the light of a consistent classification system. There are increasing reports that support previous findings on the incidence and prevalence of primary angle-closure glaucoma in different ethnic groups. There have also been further investigations into the mechanism and natural history of primary angle-closure glaucoma in Asian populations. International investigations into primary angle-closure glaucoma have demonstrated reproducible evidence that ethnic variations do exist. Cross-sectional studies in this area have also suggested that differences in anterior chamber depth, together with its association with peripheral anterior synechiae, may be part of the underlying mechanism behind these differences. The ideas generated need to be further explored with longitudinal data of changes in anterior chamber depth and peripheral anterior synechiae in different populations. The detailed mechanisms behind the development of angle-closure and primary angle-closure glaucoma should also be investigated.

[Studying the association between genetic polymorphism of growth factors and the development of primary open-angle glaucoma].

PubMed

Kirilenko, M Yu; Tikunova, E V; Sirotina, S S; Polonikov, A V; Bushueva, O Yu; Churnosov, M I

Primary open-angle glaucoma (POAG) is a multifactorial disease, etiopathogenesis of which largely depends on growth factors. Possessing a variety of medical and biological effects, these cytokines may influence the development and progression of POAG. to reveal the role of genetic polymorphisms of growth factors in predisposition to developing POAG that is refractory to local hypotensive therapy. The object of the study were 162 patients with stage II-III POAG, in whom local hypotensive therapy was inefficient, 90 patients with stage II-III POAG well controlled on local hypotensive therapy, and 191 controls. The material for the study was venous blood taken from the cubital vein of a proband. Isolation of genomic DNA was performed by phenol-chloroform extraction. Analysis of genetic polymorphisms of growth factors was performed through allelic discrimination. For that, synthesis of DNA was carried out via polymerase chain reaction (PCR). It is found that the T IGFR-1 genetic variant (OR=1.34) and a combination of the C VEGF-A and T IGFR-1 genetic variants (OR=1.90) are risk factors of developing POAG that is refractory to local hypotensive therapy. A statistical model for predicting such a risk has been proposed that includes: VEGF-A с.-958C>T genetic marker (rs 833,061), age, concomitant non-inflammatory ocular diseases, microvascular changes in the conjunctiva, the degree of pigmentation of the angle of the anterior chamber, and pseudoexfoliative syndrome. Recognition accuracy of the model is 90.42%. The T IGFR-1 genetic variant and a combination of the C VEGF-A and T IGFR-1 genetic variants increase the risk of developing POAG that is refractory to local hypotensive therapy.

Gonioscopy assisted transluminal trabeculotomy: an ab interno circumferential trabeculotomy for the treatment of primary congenital glaucoma and juvenile open angle glaucoma.

PubMed

Grover, Davinder S; Smith, Oluwatosin; Fellman, Ronald L; Godfrey, David G; Butler, Michelle R; Montes de Oca, Ildamaris; Feuer, William J

2015-08-01

To introduce a novel ab interno 360° trabeculotomy for treating primary congenital glaucoma (PCG) and juvenile open angle glaucoma (JOAG) and report preliminary results. A retrospective chart review of patients who underwent a gonioscopy assisted transluminal trabeculotomy (GATT) procedure by four of the authors (DSG, OS, RLF and DGG) between October 2011 and October 2013. The surgery was performed in patients ≤30 years old with a dysgenic anterior segment angle and uncontrolled PCG and JOAG. Fourteen eyes of 10 patients underwent GATT with follow-up >12 months (12-33 months; mean 20.4). Patients ranged in age from 17 months to 30 years (mean=18.4 years), and five (50%) were female patients. No complications occurred during or following surgery except for early postoperative hyphema in five (36%) of eyes, all cleared by 1 month. The mean intraocular pressure (IOP) decreased from 27.3 to 14.8 mm Hg and the mean number of medications required decreased from 2.6 to 0.86. Five eyes had a drop in IOP ≥15 mm Hg (range 15-39). The preliminary results and safety for GATT, a minimally invasive conjunctival sparing circumferential trabeculotomy, are promising and at least equivalent to previous results for ab externo trabeculotomy for the treatment of PCG and JOAG. All eyes in the study were considered a clinical success. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Factors associated with postoperative C5 palsy after expansive open-door laminoplasty: retrospective cohort study using multivariable analysis.

PubMed

Tsuji, Takashi; Matsumoto, Morio; Nakamura, Masaya; Ishii, Ken; Fujita, Nobuyuki; Chiba, Kazuhiro; Watanabe, Kota

2017-09-01

The aim of the present study was to investigate the factors associated with C5 palsy by focusing on radiological parameters using multivariable analysis. The authors retrospectively assessed 190 patients with cervical spondylotic myelopathy treated by open-door laminoplasty. Four radiographic parameters-the number of expanded lamina, C3-C7 angle, lamina open angle and space anterior to the spinal cord-were evaluated to clarify the factors associated with C5 palsy. Of the 190 patients, 11 developed C5 palsy, giving an overall incidence of 5.8%. Although the number of expanded lamina, lamina open angle and space anterior to the spinal cord were significantly larger in C5 palsy group than those in non-palsy group, a multiple logistic regression analysis revealed that only the space anterior to the spinal cord (odds ratio 2.60) was a significant independent factor associated with C5 palsy. A multiple linear regression analysis indicated that the lamina open angle was associated with the space anterior to the spinal cord and the analysis identified the following equation: space anterior to the spinal cord (mm) = 1.54 + 0.09 × lamina open angle (degree). A cut-off value of 53.5° for the lamina open angle predicted the development of C5 palsy with a sensitivity of 72.7% and a specificity of 83.2%. The larger postoperative space anterior to the spinal cord, which was associated with the lamina open angle, was positively correlated with the higher incidence of C5 palsy.

Hybrid thrusters and reaction wheels strategy for large angle rapid reorientation with high precision

NASA Astrophysics Data System (ADS)

Ye, Dong; Sun, Zhaowei; Wu, Shunan

2012-08-01

The quaternion-based, high precision, large angle rapid reorientation of rigid spacecraft is the main problem investigated in this study. The operation is accomplished via a hybrid thrusters and reaction wheels strategy where thrusters are engaged in providing a primary maneuver torque in open loop, while reaction wheels provide fine control torque to achieve high precision in closed-loop control. The inaccuracy of thrusters is handled by a variable structure control (VSC). In addition, a signum function is mixed in the switching surface in VSC to produce a maneuver to the reference attitude trajectory in a shortest distance. Detailed proofs and numerical simulation examples are presented to illustrate all the technical aspects of this work.

PLATEAU IRIS--DIAGNOSIS AND TREATMENT.

PubMed

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Relevant publications on plateau iris that were published until 2014. Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty.

Ab interno trabecular bypass surgery with iStent for open angle glaucoma

PubMed Central

Le, Jimmy T; Bicket, Amanda K; Li, Tianjing

2018-01-01

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows: The primary objective is to assess the comparative effectiveness and safety of ab interno trabecular bypass surgery with iStent or iStent inject for OAG in comparison to conventional medical, laser, or surgical treatment. A secondary objective is to examine the effectiveness and safety of iStent or iStent Inject surgery in people who have concomitant phacoemulsification. PMID:27526051

Micro-Bypass Implantation for Primary Open-Angle Glaucoma Combined with Phacoemulsification: 4-Year Follow-Up

PubMed Central

Fea, Antonio Maria; Consolandi, Giulia; Zola, Marta; Pignata, Giulia; Cannizzo, Paola; Lavia, Carlo; Rolle, Teresa; Grignolo, Federico Maria

2015-01-01

Purpose. To report the long-term follow-up results in patients with cataract and primary open-angle glaucoma (POAG) randomly assigned to cataract surgery combined with micro-bypass stent implantation or phacoemulsification alone. Methods. 36 subjects with cataract and POAG were randomized in a 1 : 2 ratio to either iStent implantation and cataract surgery (combined group) or cataract surgery alone (control group). 24 subjects agreed to be evaluated again 48 months after surgery. Patients returned one month later for unmedicated washout assessment. Results. At the long-term follow-up visit we reported a mean IOP of 15,9 ± 2,3 mmHg in the iStent group and 17 ± 2,5 mmHg in the control group (p = NS). After washout, a 14,2% between group difference in favour of the combined group was statistically significant (p = 0,02) for mean IOP reduction. A significant reduction in the mean number of medications was observed in both groups compared to baseline values (p = 0,005 in the combined group and p = 0,01 in the control group). Conclusion. Patients in the combined group maintained low IOP levels after long-term follow-up. Cataract surgery alone showed a loss of efficacy in controlling IOP over time. Both treatments reduced the number of ocular hypotensive medications prescribed. This trial is registered with: NCT00847158. PMID:26587282

Evidence-based practice guideline of Chinese herbal medicine for primary open-angle glaucoma (qingfeng -neizhang)

PubMed Central

Yang, Yingxin; Ma, Qiu-yan; Yang, Yue; He, Yu-peng; Ma, Chao-ting; Li, Qiang; Jin, Ming; Chen, Wei

2018-01-01

Abstract Background: Primary open angle glaucoma (POAG) is a chronic, progressive optic neuropathy. The aim was to develop an evidence-based clinical practice guideline of Chinese herbal medicine (CHM) for POAG with focus on Chinese medicine pattern differentiation and treatment as well as approved herbal proprietary medicine. Methods: The guideline development group involved in various pieces of expertise in contents and methods. Authors searched electronic databases include CNKI, VIP, Sino-Med, Wanfang data, PubMed, the Cochrane Library, EMBASE, as well as checked China State Food and Drug Administration (SFDA) from the inception of these databases to June 30, 2015. Systematic reviews and randomized controlled trials of Chinese herbal medicine treating adults with POAG were evaluated. Risk of bias tool in the Cochrane Handbook and evidence strength developed by the GRADE group were applied for the evaluation, and recommendations were based on the findings incorporating evidence strength. After several rounds of Expert consensus, the final guideline was endorsed by relevant professional committees. Results: CHM treatment principle and formulae based on pattern differentiation together with approved patent herbal medicines are the main treatments for POAG, and the diagnosis and treatment focusing on blood related patterns is the major domain. Conclusion: CHM therapy alone or combined with other conventional treatment reported in clinical studies together with Expert consensus were recommended for clinical practice. PMID:29595636

Pediatric cataract, myopic astigmatism, familial exudative vitreoretinopathy and primary open-angle glaucoma co-segregating in a family

PubMed Central

Hewitt, A.W.; Ruddle, J.B.; Vote, B.; Buttery, R.G.; Toomes, C.; Metlapally, R.; Li, Y.J.; Tran-Viet, K.N.; Malecaze, F.; Calvas, P.; Rosenberg, T.; Guggenheim, J.A.; Young, T.L.

2011-01-01

Purpose To describe an Australian pedigree of European descent with a variable autosomal dominant phenotype of: pediatric cortical cataract (CC), asymmetric myopia with astigmatism, familial exudative vitreoretinopathy (FEVR), and primary open-angle glaucoma (POAG). Methods Probands with CC, FEVR, and POAG were enrolled in three independent genetic eye studies in Tasmania. Genealogy confirmed these individuals were closely related and subsequent examination revealed 11 other family members with some or all of the associated disorders. Results Twelve individuals had CC thought to be of childhood onset, with one child demonstrating progressive lenticular opacification. One individual had severe retinal detachment while five others had dragged retinal vessels. Seven individuals had POAG. Seven individuals had myopia in at least one eye ≤-3 Diopters. DNA testing excluded mutations in myocilin, trabecular meshwork inducible glucocorticoid response (MYOC) and tetraspanin 12 (TSPAN12). Haplotype analysis excluded frizzled family receptor 4 (FZD4) and low density lipoprotein receptor-related protein 5 (LRP5), but only partly excluded EVR3. Multipoint linkage analysis revealed multiple chromosomal single-nucleotide polymorphisms (SNPs) of interest, but no statistically significant focal localization. Conclusions This unusual clustering of ophthalmic diseases suggests a possible single genetic cause for an apparently new cataract syndrome. This family’s clinical ocular features may reflect the interplay between retinal disease with lenticular changes and axial length in the development of myopia and glaucoma. PMID:21850187

Pediatric cataract, myopic astigmatism, familial exudative vitreoretinopathy and primary open-angle glaucoma co-segregating in a family.

PubMed

Mackey, D A; Hewitt, A W; Ruddle, J B; Vote, B; Buttery, R G; Toomes, C; Metlapally, R; Li, Y J; Tran-Viet, K N; Malecaze, F; Calvas, P; Rosenberg, T; Guggenheim, J A; Young, T L

2011-01-01

To describe an Australian pedigree of European descent with a variable autosomal dominant phenotype of: pediatric cortical cataract (CC), asymmetric myopia with astigmatism, familial exudative vitreoretinopathy (FEVR), and primary open-angle glaucoma (POAG). Probands with CC, FEVR, and POAG were enrolled in three independent genetic eye studies in Tasmania. Genealogy confirmed these individuals were closely related and subsequent examination revealed 11 other family members with some or all of the associated disorders. Twelve individuals had CC thought to be of childhood onset, with one child demonstrating progressive lenticular opacification. One individual had severe retinal detachment while five others had dragged retinal vessels. Seven individuals had POAG. Seven individuals had myopia in at least one eye ≤-3 Diopters. DNA testing excluded mutations in myocilin, trabecular meshwork inducible glucocorticoid response (MYOC) and tetraspanin 12 (TSPAN12). Haplotype analysis excluded frizzled family receptor 4 (FZD4) and low density lipoprotein receptor-related protein 5 (LRP5), but only partly excluded EVR3. Multipoint linkage analysis revealed multiple chromosomal single-nucleotide polymorphisms (SNPs) of interest, but no statistically significant focal localization. This unusual clustering of ophthalmic diseases suggests a possible single genetic cause for an apparently new cataract syndrome. This family's clinical ocular features may reflect the interplay between retinal disease with lenticular changes and axial length in the development of myopia and glaucoma.

Structure-Function Correlation Using Confocal Laser Ophthalmoscope in Primary Open-Angle Glaucoma and Pseudoexfoliative Glaucoma.

PubMed

Pappas, Theofanis; Founti, Panayiota; Yin, Xiang Jun; Koskosas, Archimidis; Anastasopoulos, Eleftherios; Salonikiou, Angeliki; Kilintzis, Vasilios; Antoniadis, Antonios; Ziakas, Nikolaos; Topouzis, Fotis

2016-04-01

To compare Heidelberg Retina Tomograph (HRT) optic disc parameters and structure-function correlation between primary open-angle glaucoma (POAG) and pseudoexfoliative glaucoma (PEXG). Prospective, observation case series. A total of 54 POAG and 33 PEXG cases, consecutively recruited from a University Glaucoma Service, underwent a comprehensive ophthalmic examination, including HRT optic disc imaging. Glaucoma definition required the presence of both structural and functional damage. One eye per subject was included in the analysis. T test, Mann-Whitney U test, and analysis of covariance were used to compare HRT parameters between POAG and PEXG, adjusting for age, mean deviation (MD) in the visual field, intraocular pressure, and disc area. The correlation between HRT and MD was assessed in each group. Cup area (P=0.048), height variation contour (P=0.016), and cup/disc area ratio (P=0.023) were higher in POAG, whereas the mean retinal nerve fiber layer thickness (P=0.048), retinal nerve fiber layer cross-section area (P=0.044), and rim area (P=0.048) were lower in POAG, compared with PEXG. The correlation of HRT parameters with MD was significant only in the POAG group. At a similar level of functional damage, POAG subjects presented with more pronounced structural damage than PEXG subjects. The correlation between HRT and visual field parameters was more evident in POAG, compared with PEXG.

The Primary open-angle glaucoma gene WDR36 functions in ribosomal RNA processing and interacts with the p53 stress–response pathway

PubMed Central

Skarie, Jonathan M.; Link, Brian A.

2008-01-01

Primary open-angle glaucoma (POAG) is a genetically complex neuropathy that affects retinal ganglion cells and is a leading cause of blindness worldwide. WDR36, a gene of unknown function, was recently identified as causative for POAG at locus GLC1G. Subsequent studies found disease-associated variants in control populations, leaving the role of WDR36 in this disease unclear. To address this issue, we determined the function of WDR36. We studied Wdr36 in zebrafish and found it is the functional homolog of yeast Utp21. Utp21 is cell essential and functions in the nucleolar processing of 18S rRNA, which is required for ribosome biogenesis. Evidence for functional homology comes from sequence alignment, ubiquitous expression, sub-cellular localization to the nucleolus and loss-of-function phenotypes that include defects in 18S rRNA processing and abnormal nucleolar morphology. Additionally, we show that loss of Wdr36 function leads to an activation of the p53 stress–response pathway, suggesting that co-inheritance of defects in p53 pathway genes may influence the impact of WDR36 variants on POAG. Although these results overall do not provide evidence for or against a role of WDR36 in POAG, they do provide important baseline information for future studies. PMID:18469340

Structural and functional brain changes in early- and mid-stage primary open-angle glaucoma using voxel-based morphometry and functional magnetic resonance imaging.

PubMed

Jiang, Ming-Ming; Zhou, Qing; Liu, Xiao-Yong; Shi, Chang-Zheng; Chen, Jian; Huang, Xiang-He

2017-03-01

To investigate structural and functional brain changes in patients with primary open-angle glaucoma (POAG) by using voxel-based morphometry based on diffeomorphic anatomical registration through exponentiated Lie algebra (VBM-DARTEL) and blood oxygenation level dependent functional magnetic resonance imaging (BOLD-fMRI), respectively.Thirteen patients diagnosed with POAG and 13 age- and sex-matched healthy controls were enrolled in the study. For each participant, high-resolution structural brain imaging and blood flow imaging were acquired on a 3.0-Tesla magnetic resonance imaging (MRI) scanner. Structural and functional changes between the POAG and control groups were analyzed. An analysis was carried out to identify correlations between structural and functional changes acquired in the previous analysis and the retinal nerve fiber layer (RNFL).Patients in the POAG group showed a significant (P < 0.001) volume increase in the midbrain, left brainstem, frontal gyrus, cerebellar vermis, left inferior parietal lobule, caudate nucleus, thalamus, precuneus, and Brodmann areas 7, 18, and 46. Moreover, significant (P < 0.001) BOLD signal changes were observed in the right supramarginal gyrus, frontal gyrus, superior frontal gyrus, left inferior parietal lobule, left cuneus, and left midcingulate area; many of these regions had high correlations with the RNFL.Patients with POAG undergo widespread and complex changes in cortical brain structure and blood flow. (ClinicalTrials.gov number: NCT02570867).

Risk Factors for Primary Open Angle Glaucoma (POAG) Progression: A Study Ruled in Torino

PubMed Central

Actis, A.G.; Versino, E.; Brogliatti, B.; Rolle, T.

2016-01-01

Purpose: Aim of this retrospective, observational study is to describe features of a population sample, affected by primary open angle glaucoma (POAG) in order to evaluate damage progression on the basis of the emerged individual risk factors. Methods: We included 190 caucasian patients (377 eyes), evaluating relationship between individual risk factors (explicative variables) and MD (Mean Deviation) of standard automated perimetry. We also considered the dependent variable NFI (Neural Fiber Index) of GDx scanning laser polarimetry. Progression has been evaluated through a statistic General Linear Model on four follow up steps (mean follow up 79 months). Results: Factors reaching statistical significance, determining a worsening of the MD variable, are: age (P<0.0001), intraocular pressure (IOP) at follow up (P < 0.0001), female gender (P<0.0001), hypertension (P< 0.0001) and familiarity (P = 0.0006). Factors reaching statistical significance, determining a worsening of the NFI variable, are only IOP at follow up (P = 0.0159) and depression (P = 0.0104). Conclusion: Results of this study confirm and enforce data coming from most recent studies: IOP remains the main risk factor for glaucoma assess and progression; age and familiarity are great risk factors as underlined in the last decades; female sex can be an important risk factors as emerged only in the last years; arterial hypertension should always be evaluated in timing of our clinic follow up. PMID:27347249

High prevalence of anxiety and depression in patients with primary open-angle glaucoma.

PubMed

Mabuchi, Fumihiko; Yoshimura, Kimio; Kashiwagi, Kenji; Shioe, Kunihiko; Yamagata, Zentaro; Kanba, Shigenobu; Iijima, Hiroyuki; Tsukahara, Shigeo

2008-01-01

To assess anxiety and depression in patients with primary open-angle glaucoma (POAG). Multicenter prospective case-control study. Two hundred thirty patients with POAG and 230 sex-matched and age-matched reference subjects with no chronic ocular conditions except cataracts. Anxiety and depression were evaluated using Hospital Anxiety and Depression Scale (HADS) questionnaire, which consists of 2 subscales with ranges of 0 to 21, representing anxiety (HADS-A) and depression (HADS-D). The prevalence of POAG patients with anxiety (a score of more than 10 on the HADS-A) or depression (a score of more than 10 on the HADS-D) was compared with that in the reference subjects. The prevalence of patients with depression was compared between the POAG patients with and without current beta-blocker eye drops. The prevalence (13.0%) of POAG patients with anxiety was significantly higher (P=0.030) than in the reference subjects (7.0%). The prevalence (10.9%) of POAG patients with depression was significantly higher (P=0.026) than in the reference subjects (5.2%). Between the POAG patients with and without beta-blocker eye-drops, no significant difference (P=0.93) in the prevalence of depression was noted. POAG was related to anxiety and depression. No significant relationship between the use of beta-blocker eye-drops and depression was noted.

[Correlation of intraocular pressure variation after visual field examination with 24-hour intraocular pressure variations in primary open-angle glaucoma].

PubMed

Noro, Takahiko; Nakamoto, Kenji; Sato, Makoto; Yasuda, Noriko; Ito, Yoshinori; Ogawa, Shumpei; Nakano, Tadashi; Tsuneoka, Hiroshi

2014-10-01

We retrospectively examined intraocular pressure variations after visual field examination in primary open angle glaucoma (POAG), together with its influencing factors and its association with 24-hour intraocular pressure variations. Subjects were 94 eyes (52 POAG patients) subjected to measurements of 24-hour intraocular pressure and of changes in intraocular pressure after visual field examination using a Humphrey Visual Field Analyzer. Subjects were classified into three groups according to the magnitude of variation (large, intermediate and small), and 24-hour intraocular pressure variations were compared among the three groups. Factors influencing intraocular pressure variations after visual field examination and those associated with the large variation group were investigated. Average intraocular pressure variation after visual field examination was -0.28 ± 1.90 (range - 6.0(-) + 5.0) mmHg. No significant influencing factors were identified. The intraocular pressure at 3 a.m. was significantly higher in the large variation group than other two groups (p < 0.001). Central corneal thickness was correlated with the large variation group (odds ratio = 1.04; 95% confidence interval, 1.01-1.07 ; p = 0.02). No particular tendencies in intraocular pressure variations were found after visual field examination. Increases in intraocular pressure during the night might be associated with large intraocular pressure variations after visual field examination.

Factors associated with developing a fear of falling in subjects with primary open-angle glaucoma.

PubMed

Adachi, Sayaka; Yuki, Kenya; Awano-Tanabe, Sachiko; Ono, Takeshi; Shiba, Daisuke; Murata, Hiroshi; Asaoka, Ryo; Tsubota, Kazuo

2018-02-13

To investigate the relationship between clinical risk factors, including visual field (VF) defects and visual acuity, and a fear of falling, among patients with primary open-angle glaucoma (POAG). All participants answered the following question at a baseline ophthalmic examination: Are you afraid of falling? The same question was then answered every 12 months for 3 years. A binocular integrated visual field was calculated by merging a patient's monocular Humphrey field analyzer VFs, using the 'best sensitivity' method. The means of total deviation values in the whole, superior peripheral, superior central, inferior central, and inferior peripheral VFs were calculated. The relationship between these mean VF measurements, and various clinical factors, against patients' baseline fear of falling and future fear of falling was analyzed using multiple logistic regression. Among 392 POAG subjects, 342 patients (87.2%) responded to the fear of falling question at least twice in the 3 years study period. The optimal regression model for patients' baseline fear of falling included age, gender, mean of total deviation values in the inferior peripheral VF and number of previous falls. The optimal regression equation for future fear of falling included age, gender, mean of total deviation values in the inferior peripheral VF and number of previous falls. Defects in the inferior peripheral VF area are significantly related to the development of a fear of falling.

[Efficiency of brimonidine 0.2% and dorzolamide 2% as adjunctive therapy to beta-blockers].

PubMed

Carrasco Font, C; Arias Puente, A; García Sáenz, M C; Villarejo Díaz-Maroto, I

2004-04-01

To evaluate the clinical efficiency and tolerability of brimonidine and dorzolamide twice daily as an adjunctive therapy for glaucoma patients with an inadequate response to beta-blockers therapy. This multicenter prospective analysis included 92 patients (180 eyes) with primary open-angle glaucoma or ocular hypertension on therapy beta-blockers and with intraocular pressure (IOP) greater than or equal to 18mmHg. The patients were randomly treated either with brimonidine 0.2% or dorzolamide 2% added for three months. Efficiency was determined by the reduction in 15% IOP from baseline at the first and the third month. Mean pre-treatment IOP was 22.37 DE 2.8 mmHg in the brimonidine group and 22.38 DE 2.6 mmHg in the dorzolamide group; mean post-treatment IOP decrease was 4.39 mmHg in the brimonidine group and 3.29 mmHg in the dorzolamide group. Clinical control at the first month was achieved in 78.3% and 71% of cases respectively (p=0.05). No statistical differences existed between groups for systemic adverse events. Four patients on brimonidine discontinued treatment due to local side effects. In the dorzolamide group, two patients left the treatment referring itching and three others left due to ocular allergy. This study found similar efficiency and safety when treating with brimonidine or dorzolamide as an adjunctive therapy for patients with hypertension or primary open-angle glaucoma.

Ultra-high resolution profiles of macular intra-retinal layer thicknesses and associations with visual field defects in primary open angle glaucoma

NASA Astrophysics Data System (ADS)

Chen, Qi; Huang, Shenghai; Ma, Qingkai; Lin, Huiling; Pan, Mengmeng; Liu, Xinting; Lu, Fan; Shen, Meixiao

2017-02-01

The structural characteristics of the outer retinal layers in primary open angle glaucoma (POAG) are still controversial, and these changes, along with those in the inner retinal layers, could have clinical and/or pathophysiological significance. A custom-built ultra-high resolution optical coherence tomography (UHR-OCT) combined with an automated segmentation algorithm can image and measure the eight intra-retinal layers. The purpose of this study is to determine the thickness characteristics of the macular intra-retinal layers, especially the outer layers, in POAG patients. Thirty-four POAG patients (56 eyes) and 33 normal subjects (63 eyes) were enrolled. Thickness profiles of the eight intra-retinal layers along a 6-mm length centred on the fovea at the horizontal and vertical meridians were obtained and the regional thicknesses were compared between two groups. The associations between the thicknesses of each intra-retinal layer and the macular visual field (VF) sensitivity were then analysed. POAG affected not only the inner retinal layers but also the photoreceptor layers and retinal pigment epithelium of the outer retina. However, the VF loss was correlated mainly with the damage of the inner retinal layers. UHR-OCT with automated algorithm is a useful tool in detecting microstructural changes of macula with respect to the progression of glaucoma.

Iridotomy to slow progression of angle-closure glaucoma

PubMed Central

Le, Jimmy T; Rouse, Benjamin; Gazzard, Gus

2016-01-01

This is the protocol for a review and there is no abstract. The objectives are as follows: The primary objective is to assess the role of iridotomy-compared with observation-in the prevention of visual field loss for individuals who have primary angle closure or primary angle-closure glaucoma in at least one eye. We will also examine the role of iridotomy in the prevention of elevated intraocular pressure (IOP) in individuals with narrow angles (primary angle-closure suspect) in at least one eye. PMID:27551238

Modular off-axis solar concentrator

DOEpatents

Plesniak, Adam P; Hall, John C

2015-01-27

A solar concentrator including a housing defining a vertical axis and including a receiving wall connected to a reflecting wall to define an internal volume and an opening into the internal volume, wherein the reflecting wall defines at least one primary optical element, and wherein at least a portion of the reflecting wall includes a layer of reflective material, the housing further including a cover connected to the receiving wall and the reflecting wall to seal the opening, and at least one receiver mounted on the receiving wall such that a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, the receiver including at least one photovoltaic cell.

PROSPECTS FOR JOINT GRAVITATIONAL WAVE AND SHORT GAMMA-RAY BURST OBSERVATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, J.; Evans, H.; Fairhurst, S.

2015-08-10

We present a detailed evaluation of the expected rate of joint gravitational-wave (GW) and short gamma-ray burst (GRB) observations over the coming years. We begin by evaluating the improvement in distance sensitivity of the GW search that arises from using the GRB observation to restrict the time and sky location of the source. We argue that this gives a 25% increase in sensitivity when compared to an all-sky, all-time search, corresponding to more than double the number of detectable GW signals associated with GRBs. Using this, we present the expected rate of joint observations with the advanced LIGO and Virgomore » instruments, taking into account the expected evolution of the GW detector network. We show that in the early advanced GW detector observing runs, from 2015 to 2017, there is only a small chance of a joint observation. However, as the detectors approach their design sensitivities, there is a good chance of joint observations, provided wide field GRB satellites, such as Fermi and the Inter planetary Network, continue operation. The rate will also depend critically upon the nature of the progenitor, with neutron star-black hole systems observable to greater distances than double neutron star systems. The relative rate of binary mergers and GRBs will depend upon the jet opening angle of GRBs. Consequently, joint observations, as well as accurate measurement of both the GRB rate and binary merger rates, will allow for an improved estimation of the opening angle of GRBs.« less

Undetected angle closure in patients with a diagnosis of open-angle glaucoma.

PubMed

Varma, Devesh K; Simpson, Sarah M; Rai, Amandeep S; Ahmed, Iqbal Ike K

2017-08-01

The aim of this study was to identify the proportion of patients referred to a tertiary glaucoma centre with a diagnosis of open-angle glaucoma (OAG) who were found to have angle closure glaucoma. Retrospective chart review. Consecutive new patients referred for glaucoma management to a tertiary centre between July 2010 and December 2011 were reviewed. Patients whose referrals for glaucoma assessment specified angle status as "open" were included. The data collected included glaucoma specialist's angle assessment, diagnosis, and glaucoma severity. The status of those with 180 degrees or more Shaffer angle grading of 0 was classified as "closed." From 1234 glaucoma referrals, 179 cases were specified to have a diagnosis of OAG or when angles were known to be open. Of these, 16 (8.9%) were found on examination by the glaucoma specialist to have angle closure. Pseudoexfoliation was present in 4 of 16 patients (25%) in the missed angle-closure glaucoma (ACG) group and 22 of 108 patients (13.5%) in the remaining OAG group. There was no difference found in demographic or ocular biometric parameters between those with confirmed OAG versus those with missed ACG. Almost 1 in 11 patients referred by ophthalmologists to a tertiary glaucoma centre with a diagnosis of OAG were in fact found to have angle closure. Given the different treatment approaches for ACG versus OAG, this study suggests a need to strengthen angle evaluations. Copyright © 2017 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

Primary stability of different plate positions and the role of bone substitute in open wedge high tibial osteotomy.

PubMed

Takeuchi, Ryohei; Woon-Hwa, Jung; Ishikawa, Hiroyuki; Yamaguchi, Yuichiro; Osawa, Katsunari; Akamatsu, Yasushi; Kuroda, Koichi

2017-12-01

The purpose of this study was to compare the mechanical fixation strengths of anteromedial and medial plate positions in osteotomy, and clarify the effects of bone substitute placement into the osteotomy site. Twenty-eight sawbone tibia models were used. Four different models were prepared: Group A, the osteotomy site was open and the plate position was anteromedial; Group B, bone substitutes were inserted into the osteotomy site and the plate position was anteromedial; Group C, the osteotomy site was open and the plate position was medial; and Group D, bone substitutes were inserted into the osteotomy site and the plate position was medial. The loading condition ranged from 0 to 800N and one hertz cycles were applied. Changes of the tibial posterior slope angle (TPS), stress on the plate and lateral hinge were measured. The changes in the TPS and the stress on the plate were significantly larger in Group A than in Group C. These were significantly larger in Group A than in Group B, and in Group C than in Group D. There was no significant difference between Group B and Group D, and no significant difference between knee flexion angles of 0° and 10°. Stress on the lateral hinge was significantly smaller when bone substitute was used. A medial plate position was biomechanically superior to an anteromedial position if bone substitute was not used. Bone substitute distributed the stress concentration around the osteotomy gap and prevented an increase in TPS angle regardless of the plate position. Copyright © 2017. Published by Elsevier B.V.

An observational study of bimatoprost 0.01% in treatment-naïve patients with primary open angle glaucoma or ocular hypertension: the CLEAR trial

PubMed Central

Nixon, Donald R; Simonyi, Susan; Bhogal, Meetu; Sigouin, Christopher S; Crichton, Andrew C; Discepola, Marino; Hutnik, Cindy ML; Yan, David B

2012-01-01

Background This study was designed to evaluate the occurrence and severity of ocular hyperemia in subjects with elevated intraocular pressure (IOP) due to primary open angle glaucoma (POAG) or ocular hypertension (OHT) following treatment with bimatoprost 0.01% in a real-world clinical setting. Methods This was an open-label, observational study conducted at 67 centers in Canada. Subjects with elevated IOP due to POAG or OHT instilled bimatoprost 0.01% topically as monotherapy once daily. Ocular hyperemia was graded by the investigator at baseline and weeks 6 and 12 using a photographic five-point grading scale. Change in IOP from baseline was also evaluated at these time points. This analysis includes only the subgroup of 522 subjects who were naïve to IOP-lowering medication prior to the study. Results After 12 weeks of treatment with bimatoprost 0.01%, hyperemia was graded as none-to-mild (grades 0, +0.5, or +1) for 93.3% of subjects and as moderate-to-severe (grades +2 or +3) for 6.7%. At weeks 6 and 12, most subjects (93.2% and 93.5%) had no change in hyperemia grade from baseline. IOP was reduced by 7.4 mmHg (29.8%) at week 6 and 7.7 mmHg (30.9%) at week 12 from baseline. Conclusion This real-world, observational study found that bimatoprost 0.01% instilled once daily reduced IOP by a mean of 30% from baseline without moderate or severe ocular hyperemia in 93% of treatment-naïve subjects with POAG or OHT. PMID:23269858

Efficacy and Tolerability of Travoprost 0.004%/Timolol 0.5% Fixed-Dose Combination for the Treatment of Primary Open-Angle Glaucoma or Ocular Hypertension Inadequately Controlled with Beta-Blocker Monotherapy.

PubMed

Lerner, Simon Fabian; Park, Ki Ho; Hubatsch, Douglas A; Erichev, Valeriy; Paczka, Jose A; Roberts, Timothy V

2017-01-01

Objective . To evaluate the efficacy and tolerability of travoprost 0.004%/timolol 0.5% fixed-dose combination (TTFC) in patients with open-angle glaucoma (OAG) or ocular hypertension (OHT) inadequately controlled on beta-blocker monotherapy. Methods . In this phase IV, open-label study, 156 patients on beta-blocker monotherapy with mean intraocular pressure (IOP) between 18 and 32 mmHg were randomized (no washout period) to receive TTFC for 8 weeks (TTFC group) or to continue beta-blocker monotherapy for 4 weeks followed by TTFC for the remaining 4 weeks (beta-blocker group). Results . The mean IOP (±standard deviation) at baseline in the TTFC and beta-blocker groups was 22.5 ± 2.5 mmHg and 22.2 ± 2.3 mmHg, respectively, and at weeks 4 and 8, was 16.7 ± 3.1 mmHg and 16.1 ± 3.1 mmHg, respectively, in TTFC group and 21.1 ± 3.1 mmHg and 16.1 ± 2.8 mmHg, respectively, in the beta-blocker group. There was a significant least squares mean difference between TTFC and beta-blocker in 8 a.m. IOP at week 4 (-4.6 mmHg; one-sided 95% confidence interval [-inf, -3.9]; p < 0.0001 [primary endpoint]); the upper bound of the 95% confidence interval was within the prespecified limit (<0). Both treatments were well tolerated. Conclusion . Superior IOP control was achieved with TTFC in patients with OAG or OHT previously uncontrolled with beta-blockers. No new safety findings were identified. This trial is registered with ClinicalTrials.gov NCT02003391.

Diode laser trabeculoplasty in open angle glaucoma: 50 micron vs. 100 micron spot size.

PubMed

Veljko, Andreić; Miljković, Aleksandar; Babić, Nikola

2011-01-01

The study was aimed at evaluating the efficacy of diode laser trabeculoplsaty in lowering intraocular pressure in patients with both primary open-angle glaucoma and exfoliation glaucoma by using different size of laser spot. This six-month, unmasked, controlled, prospective study included sixty-two patients with the same number of eyes, who were divided into two groups. Trabeculoplasty was performed with 50 micron and 100 micron laser spot size in the group I and group II, respectively. Other laser parameters were the same for both groups: the wave length of 532 nm, 0.1 second single emission with the power of 600-1200 mW was applied on the 180 degrees of the trabeculum. The mean intraocular pressure decrease in the 50 micron group (group 1) on day 7 was 24% from the baseline and after six-month follow-up period the intraocular pressure decrease was 29.8% (p < 0.001). In the 100 micron group (group II), the mean intraocular pressure decrease on day 7 was 26.5% and after six months it was 39% (p < 0.001).

Association of Bruch's membrane opening and optic disc morphology to axial length and visual field defects in eyes with primary open-angle glaucoma.

PubMed

Nakanishi, Hideo; Suda, Kenji; Yoshikawa, Munemitsu; Akagi, Tadamichi; Kameda, Takanori; Ikeda, Hanako Ohashi; Yokota, Satoshi; Kurimoto, Yasuo; Tsujikawa, Akitaka

2018-03-01

To examine the morphology of Bruch's membrane opening (BMO), optic disc, and peripapillary atrophy (PPA) by scanning laser ophthalmoscopy (SLO) and spectral-domain optical coherence tomography (SD-OCT), and to determine their association with the axial length and visual field defects. This was a cross-sectional study of 94 eyes of 56 subjects; 77 eyes were diagnosed with primary open-angle glaucoma and 17 eyes as normal. The margins of the optic disc were determined in the SLO images, and that of the BMO in the SD-OCT images. The ovality and area of the BMO and the optic disc were measured. The beta and gamma-PPA areas were also measured. The association of each parameter with the axial length and the mean deviation (MD) of the visual field tests was determined by generalized estimating equations (GEEs). The optic disc ovality was associated with the axial length and the MD (β = -0.47, P = 7.6 × 10 -4 and β = 0.12, P = 0.040). The BMO ovality was not significantly associated with the axial length and the MD. The BMO area was associated with the axial length (β = 0.30, P = 0.029). A larger BMO area was associated with a thinner BMO-based neuroretinal rim width (BMO-MRW) after adjustments for the MD (β = -0.30, P = 2.1 × 10 -4 ). The beta- and gamma-PPA areas were associated with the axial length (β = 0.50, P = 7.4 × 10 -5 and β = 0.62, P = 4.2 × 10 -6 ). The optic disc ovality was associated with both the axial length and MD, whereas BMO ovality was not. Attention should be paid to the influence of the axial length-related enlargement of the BMO.

Resident compliance with the american academy of ophthalmology preferred practice pattern guidelines for primary open-angle glaucoma.

PubMed

Ong, Sally S; Sanka, Krishna; Mettu, Priyatham S; Brosnan, Thomas M; Stinnett, Sandra S; Lee, Paul P; Challa, Pratap

2013-12-01

To examine resident adherence to preferred practice pattern (PPP) guidelines set up by the American Academy of Ophthalmology for follow-up care of primary open-angle glaucoma (POAG) patients. Retrospective chart review. One hundred three charts were selected for analysis from all patients with an International Classification of Diseases, Ninth Revision, code of open-angle glaucoma or its related entities who underwent a follow-up evaluation between July 2, 2003, and December 15, 2004, at the resident ophthalmology clinic in the Durham Veteran Affairs Medical Center. Follow-up visits of POAG patients were evaluated for documentation of 19 elements in accordance to PPP guidelines. Compliance rates for the 19 elements of PPP guidelines first were averaged in all charts, and then were averaged per resident and were compared among 8 residents between their first and second years of residency. The overall mean compliance rate for all 19 elements was 82.6% for all charts (n = 103), 78.8% for first-year residents, and 81.7% for second-year residents. The increase from first to second year of residency was not significant (P>0.05). Documentation rates were high (>90%) for 14 elements, including all components of the physical examination and follow-up as well as most components of the examination history and management plan. Residents documented adjusting target intraocular pressure downward, local or systemic problems with medications, and impact of visual function on daily living approximately 50% to 80% of the time. Documentation rates for components of patient education were the lowest, between 5% and 16% in all charts. Residents' compliance with PPP guidelines for a POAG follow-up visit was very high for most elements, but documentation rates for components of patient education were poor. Adherence rates to PPP guidelines can be used as a tool to evaluate and improve resident performance during training. However, further studies are needed to establish the advantages of using PPP guidelines for resident education and to determine if such assessments can lead to improved patient care. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Multifocal VEP and OCT findings in patients with primary open angle glaucoma: A cross-sectional study

PubMed Central

2012-01-01

Bakground To evaluate objectively the anatomical and functional changes of optic nerve in eyes with primary open angle glaucoma (POAG) by the joint use of optical coherence tomography (OCT) and multifocal visual evoked potentials (mfVEP). Methods 29 eyes with open angle glaucoma and visual field defects, as well as 20 eyes of 10 age-matched control normal subjects were tested. All participants underwent a complete ophthalmological examination. Moreover, Humphrey visual field test, OCT examination and recording of mfVEP were performed. Amplitude and implicit time of mfVEP, as well as RNFL thickness were measured. Differences in density components of mfVEP and in RNFL thickness among POAG eyes and control eyes were examined using Student’s t-test. Results In glaucomatous eyes the mean Retinal Response Density (RRD) was lower than normal in ring 1, 2 and 3 of mfVEP (p < 0.0001). Specifically the mean amplitude of mfVEP in POAG eyes was estimated at 34.2 ± 17.6 nV/deg2, 6.9 ± 4.8 nV/deg2 and 2.6 ± 1.6 nV/deg2 in rings 1, 2 and 3 respectively. In contrast the mean implicit time was similar to control eyes. In addition, the mean RNFL thickness in POAG eyes was estimated at 76.8 ± 26.6 μm in the superior area, 52.1 ± 16.3 μm in the temporal area, 75.9 ± 32.5 μm in the inferior area and 58.6 ± 19.4 μm in the nasal area. There was a statistically significant difference in RNFL thickness in all peripapillary areas (p < 0.0001) between POAG eyes and controls, with superior and inferior area to present the highest decrease. Conclusions Our study shows that, although Standard Automatic Perimetry is the gold standard to evaluate glaucomatous neuropathy, the joint use of mfVEP and OCT could be useful in better monitoring glaucoma progression. PMID:22856337

Anterior Segment Imaging Predicts Incident Gonioscopic Angle Closure.

PubMed

Baskaran, Mani; Iyer, Jayant V; Narayanaswamy, Arun K; He, Yingke; Sakata, Lisandro M; Wu, Renyi; Liu, Dianna; Nongpiur, Monisha E; Friedman, David S; Aung, Tin

2015-12-01

To investigate the incidence of gonioscopic angle closure after 4 years in subjects with gonioscopically open angles but varying degrees of angle closure detected on anterior segment optical coherence tomography (AS OCT; Visante; Carl Zeiss Meditec, Dublin, CA) at baseline. Prospective, observational study. Three hundred forty-two subjects, mostly Chinese, 50 years of age or older, were recruited, of whom 65 were controls with open angles on gonioscopy and AS OCT at baseline, and 277 were cases with baseline open angles on gonioscopy but closed angles (1-4 quadrants) on AS OCT scans. All subjects underwent gonioscopy and AS OCT at baseline (horizontal and vertical single scans) and after 4 years. The examiner performing gonioscopy was masked to the baseline and AS OCT data. Angle closure in a quadrant was defined as nonvisibility of the posterior trabecular meshwork by gonioscopy and visible iridotrabecular contact beyond the scleral spur in AS OCT scans. Gonioscopic angle closure in 2 or 3 quadrants after 4 years. There were no statistically significant differences in age, ethnicity, or gender between cases and controls. None of the control subjects demonstrated gonioscopic angle closure after 4 years. Forty-eight of the 277 subjects (17.3%; 95% confidence interval [CI], 12.8-23; P < 0.0001) with at least 1 quadrant of angle closure on AS OCT at baseline demonstrated gonioscopic angle closure in 2 or more quadrants, whereas 28 subjects (10.1%; 95% CI, 6.7-14.6; P < 0.004) demonstrated gonioscopic angle closure in 3 or more quadrants after 4 years. Individuals with more quadrants of angle closure on baseline AS OCT scans had a greater likelihood of gonioscopic angle closure developing after 4 years (P < 0.0001, chi-square test for trend for both definitions of angle closure). Anterior segment OCT imaging at baseline predicts incident gonioscopic angle closure after 4 years among subjects who have gonioscopically open angles and iridotrabecular contact on AS OCT at baseline. Copyright © 2015 American Academy of Ophthalmology. All rights reserved.

PLATEAU IRIS – DIAGNOSIS AND TREATMENT

PubMed Central

Stefan, Cornel; Iliescu, Daniela Adriana; Batras, Mehdi; Timaru, Cristina Mihaela; De Simone, Algerino

2015-01-01

Objectives: The objective of our study was to review the current knowledge on the diagnosis and treatment options of plateau iris configuration and syndrome. Systematic review methodology: Relevant publications on plateau iris that were published until 2014. Conclusions: Plateau iris syndrome is a form of primary angle closure glaucoma caused by a large or anteriorly positioned ciliary body that leads to mechanical obstruction of trabecular meshwork. This condition is most often found in younger patients. Plateau iris has been considered an abnormal anatomic variant of the iris that can be diagnosed on ultrasound biomicroscopy or optical coherence tomography of anterior segment. Patients with plateau iris syndrome can be recognized by the lack of response in angle opening after iridotomy. The treatment of choice in these cases is argon laser peripheral iridoplasty PMID:27373109

Open arthrolysis for elbow stiffness increases carrying angle but has no impact on functional recovery.

PubMed

Fan, Dapeng; Wang, Wei; Hildebrand, Kevin A; Fan, Cun-Yi

2016-09-09

With the exception of normal anatomic changes in the medial collateral ligament and radial head, other factors related to carrying angle changes have not been systematically studied. We reviewed patients who underwent open arthrolysis of the elbow, and evaluated if open arthrolysis could change carrying angle. We then identified factors associated with carrying angle changes. Fifty patients with a minimum of 24 months of follow-up after open arthrolysis were evaluated retrospectively. Preoperative and postoperative carrying angles were compared. The carrying angles of 36 elbows in 36 patients were unchanged after surgery (Group A), while the carrying angles of 14 elbows in 14 patients increased postoperatively (Group B). In Group A, mean postoperative extension and flexion were 7° (range 0-24°) and 125° (range 10-135°) respectively, while mean postoperative pronation and supination were 60° (range 50-80°) and 65° (range 30-85°), respectively. In Group B, mean postoperative extension and flexion were 25° (range 0-40°) and 128° (range 60-138°), while mean postoperative pronation and supination were 65° (range 45-85°) and 60° (range 45-75°), respectively. No significant difference in range of motion and Mayo Elbow Performance Score was observed between the two groups. During open arthrolysis, humeral trochlea debridement and techniques for improving forearm rotation could increase carrying angle. However, this had no impact on elbow functional recovery.

Differential protein expression in tears of patients with primary open angle and pseudoexfoliative glaucoma.

PubMed

Pieragostino, Damiana; Bucci, Sonia; Agnifili, Luca; Fasanella, Vincenzo; D'Aguanno, Simona; Mastropasqua, Alessandra; Ciancaglini, Marco; Mastropasqua, Leonardo; Di Ilio, Carmine; Sacchetta, Paolo; Urbani, Andrea; Del Boccio, Piero

2012-04-01

Primary open angle (POAG) and pseudoexfoliative glaucoma (PXG) are the most common primary and secondary forms of glaucoma, respectively. Even though the patho-physiology, aqueous humor composition, risk factors, clinical features, therapy and drug induced ocular surface changes in POAG and PXG have been widely studied, to date information concerning tear protein characterization is lacking. Tears are a source of nourishment for ocular surface tissues and a vehicle to remove local waste products, metabolized drugs and inflammatory mediators produced in several ophthalmic diseases. In glaucoma, the proteomic definition of tears may provide insights concerning patho-physiology of the disease and ocular surface modifications induced by topical therapy. Our study aimed at characterizing protein patterns in tears of patients with medically controlled POAG and PXG. A comparative tears proteomic analysis by label-free LC-MS(E) highlighted differences in the expression of several proteins in the two glaucoma sub-types and control subjects, highlighting inflammation pathways expressed in both diseases. Results were independently reconfirmed by SDS-PAGE and linear MALDI-TOF MS, validating altered levels of Lysozyme C, Lipocalin-1, Protein S100, Immunoglobulins and Prolactin Inducible Protein. Moreover, we found a differential pattern of phosphorylated Cystatin-S that distinguishes the two pathologies. The most relevant results suggest that in both pathologies there may be active inflammation pathways related to the disease and/or induced by therapy. We show, for the first time, tear protein patterns expressed under controlled intraocular pressure conditions in POAG and PXG subjects. These findings could help in the understanding of molecular machinery underlying these ophthalmologic diseases, resulting in early diagnosis and more specific therapy.

Tank-Binding Kinase 1 (TBK1) Gene and Open-Angle Glaucomas (An American Ophthalmological Society Thesis)

PubMed Central

Fingert, John H.; Robin, Alan L.; Scheetz, Todd E.; Kwon, Young H.; Liebmann, Jeffrey M.; Ritch, Robert; Alward, Wallace L.M.

2016-01-01

Purpose To investigate the role of TANK-binding kinase 1 (TBK1) gene copy-number variations (ie, gene duplications and triplications) in the pathophysiology of various open-angle glaucomas. Methods In previous studies, we discovered that copy-number variations in the TBK1 gene are associated with normal-tension glaucoma. Here, we investigated the prevalence of copy-number variations in cohorts of patients with other open-angle glaucomas—juvenile-onset open-angle glaucoma (n=30), pigmentary glaucoma (n=209), exfoliation glaucoma (n=225), and steroid-induced glaucoma (n=79)—using a quantitative polymerase chain reaction assay. Results No TBK1 gene copy-number variations were detected in patients with juvenile-onset open-angle glaucoma, pigmentary glaucoma, or steroid-induced glaucoma. A TBK1 gene duplication was detected in one (0.44%) of the 225 exfoliation glaucoma patients. Conclusions TBK1 gene copy-number variations (gene duplications and triplications) have been previously associated with normal-tension glaucoma. An exploration of other open-angle glaucomas detected a TBK1 copy-number variation in a patient with exfoliation glaucoma, which is the first example of a TBK1 mutation in a glaucoma patient with a diagnosis other than normal-tension glaucoma. A broader phenotypic range may be associated with TBK1 copy-number variations, although mutations in this gene are most often detected in patients with normal-tension glaucoma. PMID:27881886

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chesler, Paul M.; Rajagopal, Krishna

We calculate how the energy and the opening angle of jets in N = 4SYM theory evolve as they propagate through the strongly coupled plasma of that theory. We define the rate of energy loss dE jet/dx and the jet opening angle in a straightforward fashion directly in the gauge theory before calculating both holographically, in the dual gravitational description. In this way, we rederive the previously known result for dE jet/dx without the need to introduce a finite slab of plasma. We obtain a striking relationship between the initial opening angle of the jet, which is to say themore » opening angle that it would have had if it had found itself in vacuum instead of in plasma, and the thermalization distance of the jet. Via this relationship, we show that N = 4SYM jets with any initial energy that have the same initial opening angle and the same trajectory through the plasma experience the same fractional energy loss. We also provide an expansion that describes how the opening angle of the N = 4SYM jets increases slowly as they lose energy, over the fraction of their lifetime when their fractional energy loss is not yet large. In conclusion, we close by looking ahead toward potential qualitative lessons from our results for QCD jets produced in heavy collisions and propagating through quark-gluon plasma.« less

Tank-Binding Kinase 1 (TBK1) Gene and Open-Angle Glaucomas (An American Ophthalmological Society Thesis).

PubMed

Fingert, John H; Robin, Alan L; Scheetz, Todd E; Kwon, Young H; Liebmann, Jeffrey M; Ritch, Robert; Alward, Wallace L M

2016-08-01

To investigate the role of TANK-binding kinase 1 ( TBK1 ) gene copy-number variations (ie, gene duplications and triplications) in the pathophysiology of various open-angle glaucomas. In previous studies, we discovered that copy-number variations in the TBK1 gene are associated with normal-tension glaucoma. Here, we investigated the prevalence of copy-number variations in cohorts of patients with other open-angle glaucomas-juvenile-onset open-angle glaucoma (n=30), pigmentary glaucoma (n=209), exfoliation glaucoma (n=225), and steroid-induced glaucoma (n=79)-using a quantitative polymerase chain reaction assay. No TBK1 gene copy-number variations were detected in patients with juvenile-onset open-angle glaucoma, pigmentary glaucoma, or steroid-induced glaucoma. A TBK1 gene duplication was detected in one (0.44%) of the 225 exfoliation glaucoma patients. TBK1 gene copy-number variations (gene duplications and triplications) have been previously associated with normal-tension glaucoma. An exploration of other open-angle glaucomas detected a TBK1 copy-number variation in a patient with exfoliation glaucoma, which is the first example of a TBK1 mutation in a glaucoma patient with a diagnosis other than normal-tension glaucoma. A broader phenotypic range may be associated with TBK1 copy-number variations, although mutations in this gene are most often detected in patients with normal-tension glaucoma.

What was Glaucoma Called Before the 20th Century?

PubMed Central

Leffler, Christopher T.; Schwartz, Stephen G.; Giliberti, Francesca M.; Young, Matthew T.; Bermudez, Dennis

2015-01-01

Glaucoma involves a characteristic optic neuropathy, often with elevated intraocular pressure. Before 1850, poor vision with a normal eye appearance, as occurs in primary open-angle glaucoma, was termed amaurosis, gutta serena, or black cataract. Few observers noted palpable hardness of the eye in amaurosis. On the other hand, angle-closure glaucoma can produce a green or gray pupil, and therefore was called, variously, glaucoma (derived from the Greek for glaucous, a nonspecific term connoting blue, green, or light gray) and viriditate oculi. Angle closure, with palpable hardness of the eye, mydriasis, and anterior prominence of the lens, was described in greater detail in the 18th and 19th centuries. The introduction of the ophthalmoscope in 1850 permitted the visualization of the excavated optic neuropathy in eyes with a normal or with a dilated greenish-gray pupil. Physicians developed a better appreciation of the role of intraocular pressure in both conditions, which became subsumed under the rubric “glaucoma”. PMID:26483611

Simultaneous Implantation of an Ahmed and Baerveldt Glaucoma Drainage Device for Uncontrolled Intraocular Pressure in Advanced Glaucoma.

PubMed

Rao, Veena S; Christenbury, Joseph; Lee, Paul; Allingham, Rand; Herndon, Leon; Challa, Pratap

2017-02-01

To evaluate efficacy and safety of a novel technique, simultaneous implantation of Ahmed and Baerveldt shunts, for improved control of intraocular pressure (IOP) in advanced glaucoma with visual field defects threatening central fixation. Retrospective case series; all patients receiving simultaneous Ahmed and Baerveldt implantation at a single institution between October 2004 and October 2009 were included. Records were reviewed preoperatively and at postoperative day 1, week 1, month 1, month 3, month 6, year 1, and yearly until year 5. Outcome measures included IOP, best-corrected visual acuity, visual field mean deviation, cup to disc ratio, number of glaucoma medications, and complications. Fifty-nine eyes were identified; mean (±SD) follow-up was 26±23 months. Primary open-angle glaucoma was most common (n=37, 63%). Forty-six eyes (78%) had prior incisional surgery. Mean preoperative IOP was 25.5±9.8 mm Hg. IOP was reduced 50% day 1 (P<0.001, mean 12.7±7.0 mm Hg), which persisted throughout follow-up. At year 1, cup to disc ratio and mean deviation were stable with decreased best-corrected visual acuity from logMAR 0.72±0.72(20/100) to 1.06±1.13(20/200) (P=0.007). The Kaplan-Meier survival analysis showed median and mean survival of 1205 and 829±91 days, respectively. Complication rate was 47%. IOP is markedly reduced postoperative day 1 following double glaucoma tube implantation with effects persisting over postoperative year 1 and up to year 5. Complications were higher than that seen in reports of single shunt implantation, which may be explained by patient complexity in this cohort. This technique may prove a promising novel approach for management of uncontrolled IOP in advanced glaucoma.

Primary angle closure glaucoma in a myopic kinship.

PubMed

Hagan, J C; Lederer, C M

1985-03-01

Three related myopic individuals with primary angle closure glaucoma are reported. They had true myopia and not pseudomyopia secondary to increased lenticular index of refraction. We believe one of these individuals (-8.62 spherical equivalent) to have the most myopic case of primary angle closure glaucoma reported in the literature. Although myopia is associated with anatomical factors that offer considerable protection from primary angle closure glaucoma, its presence does not eliminate the possibility of this disease. Laser iridectomy was effective in the treatment of these patients.

46 CFR 172.065 - Damage stability.

Code of Federal Regulations, 2011 CFR

2011-10-01

... of sinkage, heel, and trim, must be below the lower edge of an opening through which progressive... sliding watertight door; or (vi) Side scuttle of the non-opening type. (2) Heel angle. The maximum angle of heel must not exceed 25 degrees, except that this angle may be increased to 30 degrees if no deck...

46 CFR 172.065 - Damage stability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... of sinkage, heel, and trim, must be below the lower edge of an opening through which progressive... sliding watertight door; or (vi) Side scuttle of the non-opening type. (2) Heel angle. The maximum angle of heel must not exceed 25 degrees, except that this angle may be increased to 30 degrees if no deck...

Recombinational and physical mapping of the locus for primary open-angle glaucoma (GLC1A) on chromosome 1q23-q25

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belmouden, A.; Adam, M.F.; De Dinechin, S.D.

1997-02-01

Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness in industrialized countries. A locus for juvenile-onset POAG, GLC1A, has been mapped to 1q21-q31 in a 9-cM interval. With recombinant haplotypes, we have now reduced the GLC1A interval to a maximum of 3 cM, between the D1S452/NGA1/D1S210 and NGA5 loci. These loci are 2.8 Mb apart on a 4.7-Mb contig that we have completed between the D1S2851 and D1S218 loci and that includes 96 YAC clones and 48 STSs. The new GLC1A interval itself is now covered by 25 YACs, 30 STSs, and 16 restriction enzyme site landmarks. Themore » lack of a NotI site suggests that the region has few CpG islands and a low gene content. This is compatible with its predominant cytogenetic location on the 1q24 G-band. Finally, we have excluded important candidate genes, including genes coding for three ATPases (AMB1, ATP2B4, ATPlA2), an ion channel (VDAC4), antithrombine III (AT3), and prostaglandin synthase (PTGS2). Our results provide a basis to identify the GLC1A gene. 59 refs., 3 figs., 3 tabs.« less

Current concepts on primary open-angle glaucoma genetics: a contribution to disease pathophysiology and future treatment

PubMed Central

Gemenetzi, M; Yang, Y; Lotery, A J

2012-01-01

Glaucoma is a common, complex, heterogenous disease and it constitutes the major cause of irreversible blindness worldwide. Primary open-angle glaucoma (POAG) is the most common type of glaucoma in all populations. Most of the molecular mechanisms leading to POAG development are still unknown. Gene mutations in various populations have been identified by genetic studies and a genetic basis for glaucoma pathogenesis has been established. Linkage analysis and association studies are genetic approaches in the investigation of the genetic basis of POAG. Genome-wide association studies (GWAS) are more powerful compared with linkage analysis in discovering genes of small effect that might contribute to the development of the disease. POAG links to at least 20 genetic loci, but only 2 genes identified in these loci, myocilin and optineurin, are considered as well-established glaucoma-causing genes, whereas the role of other loci, genes, and variants implicated in the development of POAG remains controversial. Gene mutations associated with POAG result in retinal ganglion cell death, which is the common outcome of pathogenetic mechanisms in glaucoma. In future, if the sensitivity and specificity of genotyping increases, it may be possible to screen individuals routinely for disease susceptibility. This review is an update on the latest progress of genetic studies associated with POAG. It emphasizes the correlation of recent achievements in genetics with glaucoma pathophysiology, glaucoma treatment perspectives, and the possibility of future prevention of irreversible visual loss caused by the disease. PMID:22173078

Plasminogen activator inhibitor-1 4G/5G gene polymorphism and primary open-angle glaucoma

PubMed Central

Weger, Martin; Faschinger, Christoph; Schmut, Otto; Renner, Wilfried

2008-01-01

Purpose Alterations of the plasmin system have been suggested to participate in the multifactorial pathogenesis of primary open-angle glaucoma (POAG). The main physiological inhibitor of the plasmin system is plasminogen activator inhibitor-1 (PAI-1), which leads to decreased degradation of extracellular material. Interestingly, elevated PAI-1 levels in the aqueous humor of patients with POAG have been reported. A common polymorphism within the promoter region (PAI-1 4G/5G) has previously been shown to reduce the gene transcription rate of PAI-1. The purpose of the present study was to investigate a hypothesized association between PAI-1 4G/5G and the presence of POAG in a Caucasian population. Methods The present case-control study comprised 212 unrelated patients with POAG and 212 healthy control subjects, matched for age and sex. Genotyping of PAI-1 4G/5G polymorphisms was done using polymerase chain reaction. Results Allelic frequencies and genotype distributions of PAI-1 4G/5G did not significantly differ between patients with POAG and control subjects (PAI-1 4G/5G: 29.7% versus 29.7%). Presence of the PAI-1 4G-allele was associated with a nonsignificant odds ratio of 0.98 (95% confidence interval: 0.74–1.30) for POAG. Conclusions Our data suggest that PAI-1 4G/5G itself is unlikely to be a major risk factor among Caucasian patients with POAG. PMID:18615155

Retinal Adaptation Abnormalities in Primary Open-Angle Glaucoma

PubMed Central

Dul, Mitchell; Ennis, Robert; Radner, Shira; Lee, Barry; Zaidi, Qasim

2015-01-01

Purpose. Dynamic color and brightness adaptation are crucial for visual functioning. The effects of glaucoma on retinal ganglion cells (RGCs) could compromise these functions. We have previously used slow dynamic changes of light at moderate intensities to measure the speed and magnitude of subtractive adaptation in RGCs. We used the same procedure to test if RGC abnormalities cause slower and weaker adaptation for patients with glaucoma when compared to age-similar controls. We assessed adaptation deficits in specific classes of RGCs by testing along the three cardinal color axes that isolate konio, parvo, and magno RGCs. Methods. For one eye each of 10 primary open-angle glaucoma patients and their age-similar controls, we measured the speed and magnitude of adapting to 1/32 Hz color modulations along the three cardinal axes, at central fixation and 8° superior, inferior, nasal, and temporal to fixation. Results. In all 15 comparisons (5 locations × 3 color axes), average adaptation was slower and weaker for glaucoma patients than for controls. Adaptation developed slower at central targets than at 8° eccentricities for controls, but not for patients. Adaptation speed and magnitude differed between affected and control eyes even at retinal locations showing no visual field loss with clinical perimetry. Conclusions. Neural adaptation is weaker in glaucoma patients for all three classes of RGCs. Since adaptation abnormalities are manifested even at retinal locations not exhibiting a visual field loss, this novel form of assessment may offer a functional insight into glaucoma and an early diagnosis tool. PMID:25613950

A Small Disc Area Is a Risk Factor for Visual Field Loss Progression in Primary Open-Angle Glaucoma: The Glaucoma Stereo Analysis Study.

PubMed

Kitaoka, Yasushi; Tanito, Masaki; Yokoyama, Yu; Nitta, Koji; Katai, Maki; Omodaka, Kazuko; Nakazawa, Toru

2018-01-01

The Glaucoma Stereo Analysis Study, a cross-sectional multicenter collaborative study, used a stereo fundus camera (nonmyd WX) to assess various morphological parameters of the optic nerve head (ONH) in glaucoma patients. We compared the associations of each parameter between the visual field loss progression group and no-progression group. The study included 187 eyes of 187 patients with primary open-angle glaucoma or normal-tension glaucoma. We divided the mean deviation (MD) slope values of all patients into the progression group (<-0.3 dB/year) and no-progression group (≧-0.3 dB/year). ONH morphological parameters were calculated with prototype analysis software. The correlations between glaucomatous visual field progression and patient characteristics or each ONH parameter were analyzed with Spearman's rank correlation coefficient. The MD slope averages in the progression group and no-progression group were -0.58 ± 0.28 dB/year and 0.05 ± 0.26 dB/year, respectively. Among disc parameters, vertical disc width (diameter), disc area, cup area, and cup volume in the progression group were significantly less than those in the no-progression group. Logistic regression analysis revealed a significant association between the visual field progression and disc area (odds ratio 0.49/mm 2 disc area). A smaller disc area may be associated with more rapid glaucomatous visual field progression.

Correlation between central corneal thickness and visual field defects, cup to disc ratio and retinal nerve fiber layer thickness in primary open angle glaucoma patients.

PubMed

Sarfraz, Muhammad Haroon; Mehboob, Mohammad Asim; Haq, Rana Intisar Ul

2017-01-01

To evaluate the correlation between Central Corneal Thickness (CCT) and Visual Field (VF) defect parameters like Mean Deviation (MD) and Pattern Standard Deviation (PSD), Cup-to-Disc Ratio (CDR) and Retinal Nerve Fibre Layer Thickness (RNFL-T) in Primary Open-Angle Glaucoma (POAG) patients. This cross sectional study was conducted at Armed Forces Institute of Ophthalmology (AFIO), Rawalpindi from September 2015 to September 2016. Sixty eyes of 30 patients with diagnosed POAG were analysed. Correlation of CCT with other variables was studied. Mean age of study population was 43.13±7.54 years. Out of 30 patients, 19 (63.33%) were males and 11 (36.67%) were females. Mean CCT, MD, PSD, CDR and RNFL-T of study population was 528.57±25.47µm, -9.11±3.07, 6.93±2.73, 0.63±0.13 and 77.79±10.44µm respectively. There was significant correlation of CCT with MD, PSD and CDR (r=-0.52, p<0.001; r=-0.59, p<0.001;r=-0.41, p=0.001 respectively). The correlation of CCT with RNFL-T was not statistically significant (r=-0.14, p=0.284). Central corneal thickness had significant correlation with visual field parameters like mean deviation and pattern standard deviation, as well as with cup-to-disc ratio. However, central corneal thickness had no significant relationship with retinal nerve fibre layer thickness.

Prevalence and risk factors for primary open-angle glaucoma in a rural northeast China population: a population-based survey in Bin County, Harbin

PubMed Central

Sun, J; Zhou, X; Kang, Y; Yan, L; Sun, X; Sui, H; Qin, D; Yuan, H

2012-01-01

Purpose To estimate the prevalence and associated risk factors of primary open-angle glaucoma (POAG) in a rural population in northeast China. Methods A population-based survey was conducted within Bin County, Harbin of northeast China. Glaucoma was diagnosed using International Society of Geographical and Epidemiological Ophthalmology criteria. All the subjects underwent a complete ophthalmic examination. Results A total of 4956 (86.0%) of 5762 subjects aged 40 years or older were examined. The mean intraocular pressure (IOP) of right eyes was 14.0 (95% confidence interval (CI), 13.9 to 14.1) mm Hg. The prevalence of POAG was 0.71% (35/4956, 95% CI, 0.47 to 0.93). In these POAG subjects, 17 (48.6%) had elevated IOP >21 mm Hg in either eye, 3 (8.8%) participants had been treated by laser trabeculoplasty or trabeculectomy and were known to have POAG. Vision impairment to varying degrees was present in 20 subjects (58.8%) with 1 subject blind in both eyes and 8 subjects blind in one eye. On multivariate analysis, age, family history of glaucoma, systemic hypertension, and IOP were regarded as significant independent risk factors. Conclusions POAG is a disease of serious consequence and of low diagnosis and treatment rates in rural northeast China. Age, family history of glaucoma, systemic hypertension, and IOP remain as significant independent risk factors for POAG. PMID:22157917

The Influence of Structure Heights and Opening Angles of Micro- and Nanocones on the Macroscopic Surface Wetting Properties

NASA Astrophysics Data System (ADS)

Schneider, Ling; Laustsen, Milan; Mandsberg, Nikolaj; Taboryski, Rafael

2016-02-01

We discuss the influence of surface structure, namely the height and opening angles of nano- and microcones on the surface wettability. We show experimental evidence that the opening angle of the cones is the critical parameter on sample superhydrophobicity, namely static contact angles and roll-off angles. The textured surfaces are fabricated on silicon wafers by using a simple one-step method of reactive ion etching at different processing time and gas flow rates. By using hydrophobic coating or hydrophilic surface treatment, we are able to switch the surface wettability from superhydrophilic to superhydrophobic without altering surface structures. In addition, we show examples of polymer replicas (polypropylene and poly(methyl methacrylate) with different wettability, fabricated by injection moulding using templates of the silicon cone-structures.

Evaluation of the Association Between Common Genetic Variants Near the ABCA1 Gene and Primary Angle Closure Glaucoma in a Han Chinese Population.

PubMed

Luo, Huaichao; Chen, Yuhong; Ye, Zimeng; Sun, Xinghuai; Shi, Yi; Luo, Qian; Gong, Bo; Shuai, Ping; Yang, Jiyun; Zhou, Yu; Liu, Xiaoqi; Zhang, Kaijiong; Tan, Chang; Li, Yuanfeng; Lin, Ying; Yang, Zhenglin

2015-10-01

Recently, three large genome-wide association studies have identified multiple variants associated with primary open angle glaucoma (POAG) near the ABCA1 gene. Considering that POAG and primary angle closure glaucoma (PACG) share many similar clinical manifestations, the present study was conducted to investigate whether these genetic variants were also associated with PACG in a Han Chinese population. A case-control association study of 1122 cases (PACG/PAC) and 1311 normal, matched controls was undertaken. Seven single-nucleotide polymorphisms (SNPs) near the ABCA1 gene, including rs2422493, rs2487042, rs2472496, rs2472493, rs2487032, rs2472459, and rs2472519, were genotyped. Genotype and allele frequencies were assessed using χ² tests. Linkage disequilibrium (LD) structure was analyzed by computer software. Among the SNPs genotyped, no association was observed between these SNPs and PACG. However, we discovered that two haplotypes, CATTTAC (corrected P = 0.048) and CGCCCGC (corrected P = 0.048), remained significantly associated with PACG/PAC after Bonferroni correction. Subjects with the CATTTAC haplotype have a 1.71-fold increased possibility of having PACG/PAC, whereas subjects with the CGCCCGC haplotype have 0.47-fold decreased possibility of developing PACG. Our findings suggest that the genetic backgrounds of PACG and POAG might be different. However, whether or not ABCA1 plays a role in the development of PACG is still not made certain by this study. Thus, further research is needed to find the role of ABCA1 in the progress of PACG.

Modified Angle's Classification for Primary Dentition.

PubMed

Chandranee, Kaushik Narendra; Chandranee, Narendra Jayantilal; Nagpal, Devendra; Lamba, Gagandeep; Choudhari, Purva; Hotwani, Kavita

2017-01-01

This study aims to propose a modification of Angle's classification for primary dentition and to assess its applicability in children from Central India, Nagpur. Modification in Angle's classification has been proposed for application in primary dentition. Small roman numbers i/ii/iii are used for primary dentition notation to represent Angle's Class I/II/III molar relationships as in permanent dentition, respectively. To assess applicability of modified Angle's classification a cross-sectional preschool 2000 children population from central India; 3-6 years of age residing in Nagpur metropolitan city of Maharashtra state were selected randomly as per the inclusion and exclusion criteria. Majority 93.35% children were found to have bilateral Class i followed by 2.5% bilateral Class ii and 0.2% bilateral half cusp Class iii molar relationships as per the modified Angle's classification for primary dentition. About 3.75% children had various combinations of Class ii relationships and 0.2% children were having Class iii subdivision relationship. Modification of Angle's classification for application in primary dentition has been proposed. A cross-sectional investigation using new classification revealed various 6.25% Class ii and 0.4% Class iii molar relationships cases in preschool children population in a metropolitan city of Nagpur. Application of the modified Angle's classification to other population groups is warranted to validate its routine application in clinical pediatric dentistry.

Impact of emerging technologies on future combat aircraft agility

NASA Technical Reports Server (NTRS)

Nguyen, Luat T.; Gilert, William P.

1990-01-01

The foreseeable character of future within-visual-range air combat entails a degree of agility which calls for the integration of high-alpha aerodynamics, thrust vectoring, intimate pilot/vehicle interfaces, and advanced weapons/avionics suites, in prospective configurations. The primary technology-development programs currently contributing to these goals are presently discussed; they encompass the F-15 Short Takeoff and Landing/Maneuver Technology Demonstrator Program, the Enhanced Fighter Maneuverability Program, the High Angle-of-Attack Technology Program, and the X-29 Technology Demonstrator Program.

Digital video system for on-line portal verification

NASA Astrophysics Data System (ADS)

Leszczynski, Konrad W.; Shalev, Shlomo; Cosby, N. Scott

1990-07-01

A digital system has been developed for on-line acquisition, processing and display of portal images during radiation therapy treatment. A metal/phosphor screen combination is the primary detector, where the conversion from high-energy photons to visible light takes place. A mirror angled at 45 degrees reflects the primary image to a low-light-level camera, which is removed from the direct radiation beam. The image registered by the camera is digitized, processed and displayed on a CRT monitor. Advanced digital techniques for processing of on-line images have been developed and implemented to enhance image contrast and suppress the noise. Some elements of automated radiotherapy treatment verification have been introduced.

Anomalous contact angle hysteresis of a captive bubble: advancing contact line pinning.

PubMed

Hong, Siang-Jie; Chang, Feng-Ming; Chou, Tung-He; Chan, Seong Heng; Sheng, Yu-Jane; Tsao, Heng-Kwong

2011-06-07

Contact angle hysteresis of a sessile drop on a substrate consists of continuous invasion of liquid phase with the advancing angle (θ(a)) and contact line pinning of liquid phase retreat until the receding angle (θ(r)) is reached. Receding pinning is generally attributed to localized defects that are more wettable than the rest of the surface. However, the defect model cannot explain advancing pinning of liquid phase invasion driven by a deflating bubble and continuous retreat of liquid phase driven by the inflating bubble. A simple thermodynamic model based on adhesion hysteresis is proposed to explain anomalous contact angle hysteresis of a captive bubble quantitatively. The adhesion model involves two solid–liquid interfacial tensions (γ(sl) > γ(sl)′). Young’s equation with γ(sl) gives the advancing angle θ(a) while that with γ(sl)′ due to surface rearrangement yields the receding angle θ(r). Our analytical analysis indicates that contact line pinning represents frustration in surface free energy, and the equilibrium shape corresponds to a nondifferential minimum instead of a local minimum. On the basis of our thermodynamic model, Surface Evolver simulations are performed to reproduce both advancing and receding behavior associated with a captive bubble on the acrylic glass.

Preservative-free versus preserved latanoprost eye drops in patients with open-angle glaucoma or ocular hypertension.

PubMed

Aptel, Florent; Choudhry, Reena; Stalmans, Ingeborg

2016-08-01

This study compared the efficacy, safety, and pharmacokinetics of a preservative-free latanoprost formulation to an established, benzalkonium chloride (BAK) containing formulation for the treatment of open-angle glaucoma or ocular hypertension. This was a phase II, randomized, cross-over, investigator-masked, multi-center, pilot study (NCT01494753). A total of 30 untreated adult patients (aged ≥18 years) with primary open angle glaucoma, pseudo-exfoliative glaucoma, pigmentary glaucoma, or ocular hypertension received either preservative-free or preserved latanoprost once daily in both eyes for 6 weeks, before crossing over to receive the other treatment. Efficacy (intraocular pressure [IOP] at 8 am, midday, 4 pm and 8 pm, and global efficacy assessment by investigator), safety (adverse events, ocular symptoms and global tolerance, slit lamp examination, funduscopy, visual field examination, visual acuity, and heart rate), and pharmacokinetics were assessed at Days 0, 42, and 84. Both treatments resulted in a reduction in IOP that was similar for the preservative-free and the preserved formulation at all time points. Similarly, the overall diurnal reduction was similar in both groups (6.3 mmHg [27.9% reduction] and 6.4 mmHg [28.1% reduction] for preserved and preservative-free latanoprost, respectively). There were no differences in global efficacy assessment or in the safety and tolerance of each treatment. Systemic concentrations of latanoprost were very low; AUC0-30 and Cmax were lower and tmax was longer for preservative-free latanoprost. Preservative-free latanoprost showed similar efficacy at all time points compared to BAK preservative containing formulation, with no difference in tolerance, allowing progression to phase III clinical development.

EP3/FP dual receptor agonist ONO-9054 administered morning or evening to patients with open-angle glaucoma or ocular hypertension: results of a randomised crossover study

PubMed Central

Berlin, Michael S; Rowe-Rendleman, Cheryl; Ahmed, Ike; Ross, Douglas T; Fujii, Akifumi; Ouchi, Takafumi; Quach, Christine; Wood, Andrew; Ward, Caroline L

2016-01-01

Background/aims The novel prostaglandin E (EP) 3 and prostaglandin F (FP) receptor agonist ONO-9054 is effective in lowering intraocular pressure (IOP) in patients with ocular hypertension and open-angle glaucoma when administered once daily. This study compares the effects of morning (AM) versus evening (PM) dosing of ONO-9054 on tolerability and IOP lowering. Methods This was a single-centre, randomised, double-masked, two-sequence, placebo-controlled crossover study in 12 subjects with bilateral primary open-angle glaucoma or ocular hypertension. Two 14-day crossover regimens were separated by a 2-week washout: ONO-9054 (1 drop to each eye) in the morning (07:00) and vehicle in the evening (19:00) and vice versa. IOP was measured multiple times during select days. Ocular examinations also evaluated safety and tolerability. Results Mild ocular hyperaemia, reported by six subjects with PM dosing, was the most frequent adverse event. Mild to moderate dryness was also slightly more frequent after PM dosing. Maximum IOP reduction from baseline occurred on day 2 with decreases from baseline of −7.4 mm Hg (−30.8%) for AM dosing and −9.1 mm Hg, (−38.0%) for PM dosing; after 14 days, mean reduction in IOP was −6.8 mm Hg (−28.6%) for AM dosing and −7.5 mm Hg (−31.0%) for PM dosing. Conclusions PM dosing of ONO-0954 was associated with a slightly increased frequency of mild hyperaemia and mild to moderate dryness. Both dosing schedules provided sustained reduction in IOP. Trial registration number NCT01670266. PMID:26453641

Surgical Outcomes of Gonioscopy-assisted Transluminal Trabeculotomy (GATT) in Patients With Open-angle Glaucoma.

PubMed

Rahmatnejad, Kamran; Pruzan, Noelle L; Amanullah, Sarah; Shaukat, Bilal A; Resende, Arthur F; Waisbourd, Michael; Zhan, Tingting; Moster, Marlene R

2017-12-01

To evaluate the efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) in patients with open-angle glaucoma. A retrospective chart review of adult patients who underwent GATT due to inadequately controlled intraocular pressure (IOP) or intolerance to medication. Main outcome measures were success rate, IOP, and number of glaucoma medications. Success was defined as IOP reduction >20% from baseline or IOP between 5 to 21 mm Hg, and no need for further glaucoma surgery. When success criteria were not met for any postoperative visit >3 months after surgery, failure was determined. In total, 66 patients, average age 62.9±14.9 years (50.8% female) were included in the analysis. Average follow-up was 11.9 months (range, 3 to 30 mo) and overall success rate was 63.0%. Mean IOP was 26.1±9.9 mm Hg preoperatively and 14.6±4.7 mm Hg at 12 months (44% IOP decrease; P<0.001). Mean number of medications decreased from 3.1±1.1 preoperatively to 1.2±0.9 at 12 months (P<0.001). No significant differences between patients with primary open-angle glaucoma and other types of glaucoma were found.The rate of hyphema at 1 week and 1 month postoperatively was 38% and 6%, respectively. Overall GATT success rate among white and black patients was 69% and 42%, respectively, which was statistically significant (P<0.05). The future of GATT as a minimally invasive glaucoma surgery in adults seems promising. This position is supported by its low rate of long-term complications and the conjunctiva-sparing nature of the surgery.

Effect of aperture geometry on heat transfer in tilted partially open cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elsayed, M.M.; Chakroun, W.

1999-11-01

Heat transfer in cavities is receiving increasing attention because of the various applications in engineering; e.g., passive solar heating, energy conservation in buildings, solar concentrating receivers, and electronic equipment. Here, convection from a square, tilted partially open cavity was investigated experimentally. The experiment was carried out to study the effect of the aperture geometry on the heat transfer between the cavity and the surrounding air. Four different geometrical arrangements for the opening were investigated: (1) high wall slit, (2) low wall slit, (3) centered wall slit, and (4) uniform wall slots. Each opening arrangement was studied at opening ratios (i.e.,more » ratio of opening height to cavity height) of 0.25, 0.5, and 0.75. The average heat transfer coefficient between the cavity and the surrounding air was estimated for each geometrical arrangement for tilt angles ranging from {minus}90 deg to +90 deg with increments of 15 deg and at a constant heat flux Grashof number of 5.5 x 10{sup 8}. The results showed that for tilt angles between 90 and 75 deg, the heat transfer coefficient has a small value that is independent of the geometrical arrangement of the opening. The value of the heat transfer coefficient increases sharply with decreasing tilt angle until an angle value of zero degrees is reached. The increase in the heat transfer coefficient continues in the negative range of tilt angle but not in the same rate as in the positive range of the tilt angle. The uniform slot arrangement gave in general higher heat transfer coefficient than the other three arrangements of the opening. Large differences in the heat transfer coefficient were observed between the high and the low wall slits where the high wall slit is found to transfer more heat to the surroundings than the low wall slit. Correlations were developed to predict the average Nusselt number of the cavity in terms of the opening ratio and the cavity tilt angle for cavities with high wall slit, low wall slit, centered wall slit, and the uniform wall slots.« less

LAZY Genes Mediate the Effects of Gravity on Auxin Gradients and Plant Architecture1[OPEN

PubMed Central

2017-01-01

A rice (Oryza sativa) mutant led to the discovery of a plant-specific LAZY1 protein that controls the orientation of shoots. Arabidopsis (Arabidopsis thaliana) possesses six LAZY genes having spatially distinct expression patterns. Branch angle phenotypes previously associated with single LAZY genes were here studied in roots and shoots of single and higher-order atlazy mutants. The results identify the major contributors to root and shoot branch angles and gravitropic behavior of seedling hypocotyls and primary roots. AtLAZY1 is the principal determinant of inflorescence branch angle. The weeping inflorescence phenotype of atlazy1,2,4 mutants may be due at least in part to a reversal in the gravitropism mechanism. AtLAZY2 and AtLAZY4 determined lateral root branch angle. Lateral roots of the atlazy2,4 double mutant emerged slightly upward, approximately 10° greater than perpendicular to the primary root axis, and they were agravitropic. Etiolated hypocotyls of the quadruple atlazy1,2,3,4 mutant were essentially agravitropic, but their phototropic response was robust. In light-grown seedlings, the root of the atlazy2,3,4 mutant was also agravitropic but when adapted to dim red light it displayed a reversed gravitropic response. A reversed auxin gradient across the root visualized by a fluorescent signaling reporter explained the reversed, upward bending response. We propose that AtLAZY proteins control plant architecture by coupling gravity sensing to the formation of auxin gradients that override a LAZY-independent mechanism that creates an opposing gravity-induced auxin gradient. PMID:28821594

Biometric Factors Associated With Acute Primary Angle Closure: Comparison of the Affected and Fellow Eye.

PubMed

Atalay, Eray; Nongpiur, Monisha E; Baskaran, Mani; Sharma, Sourabh; Perera, Shamira A; Aung, Tin

2016-10-01

To compare ocular biometric and anterior segment parameters between the affected and fellow eye in subjects with acute primary angle closure (APAC). We evaluated 76 subjects with unilateral APAC who had undergone bilateral laser peripheral iridotomy before enrollment. Imaging was done using anterior segment optical coherence tomography and a customized software was used to measure the following: angle opening distance (AOD750); trabecular-iris space area (TISA750); iris thickness (IT750); iris curvature (ICURV); iris area (IAREA); anterior chamber depth; area and volume (ACD; ACA and ACV); anterior chamber width (ACW); anterior vault (ACD+LV); lens vault (LV); and pupil diameter (PD). We used A-scan ultrasonography to measure axial length (AL) and lens thickness (LT). Mean differences in ocular biometric and anterior segment parameters were assessed using linear mixed model adjusting for PD. A total of 53 subjects (36 females, 67.9%) with a mean age of 62.7 ± 8.1 years were analyzed after excluding 17 unanalyzable images in at least one eye. Affected eyes had shallower ACD, smaller ACA, ACV, anterior vault, TISA750, AOD750, and ICURV (all P < 0.05). Axial length, ACW, LV, LT, IAREA, and IT750 did not differ between the eyes. In the affected eyes, IT750 was significantly associated AOD750 (P < 0.05); whereas in the fellow eyes, IT750 and AL was predictive of AOD750 (all P < 0.05). Eyes with previous APAC had smaller anterior segment dimensions when compared with their fellow eyes. Iris thickness was the strongest predictor of angle width in both affected and fellow eyes.

Enterprise Education: A Deweyan Perspective

ERIC Educational Resources Information Center

Pepin, Matthias

2012-01-01

Purpose: The purpose of this paper is to propose a framework of reflection that opens the way to a fuller understanding of what is meant by learning to be enterprising in schools, particularly during the basic schooling of students (at both the primary and secondary levels). Working from Dewey's philosophy of experience, the paper advances a new…

Piloted simulator evaluation of a relaxed static stability fighter at high angle-of-attack

NASA Technical Reports Server (NTRS)

Lapins, M.; Klein, R. W.; Martorella, R. P.; Cangelosi, J.; Neely, W. R., Jr.

1982-01-01

A piloted simulator evaluation of the stability and control characteristics of a relaxed static stability fighter aircraft was conducted using a differential maneuvering simulator. The primary purpose of the simulation was to evaluate the effectiveness of the limiters in preventing departure from controlled flight. The simulation was conducted in two phases, the first consisting of open-loop point stability evaluations over a range of subsonic flight conditions, the second concentrating on closed-loop tracking of a preprogrammed target in low speed, high angle-of-attack air combat maneuvering. The command limiters were effective in preventing departure from controlled flight while permitting competent levels of sustained maneuvering. Parametric variations during the study included the effects of pitch control power and wing-body static margin. Stability and control issues were clearly shown to impact the configuration design.

Occlusal plane rotation: aesthetic enhancement in mandibular micrognathia.

PubMed

Rosen, H M

1993-06-01

Patients afflicted with extreme degrees of mandibular micrognathia typically have vertically deficient rami as well as sagittally deficient mandibular bodies. This results in deficient posterior facial height, an obtuse gonial angle, excessively steep occlusal and mandibular planes, and a compensatory increase in anterior facial height. The entire maxillomandibular complex is overrotated in a clockwise direction. Standard orthognathic surgical correction fails to address this rotational deformity. As a consequence, the achieved projection of the lower face is inadequate, posterior facial height is further reduced, and occlusal and mandibular planes remain steep. Eleven patients with severe mandibular micrognathia underwent a surgical correction involving occlusal plane rotation to its normal orientation relative to Frankfort horizontal. This was accomplished by Le Fort I osteotomy to shorten the anterior maxilla (creating open bites in seven patients and making preexisting open bites worse in four patients) and sagittal split ramus osteotomies to advance and rotate the mandibular body counterclockwise, thus closing the surgically produced open bite. Counterclockwise rotation of the mandible afforded significantly greater sagittal displacement at the B point (mean 17 mm) than at the first molar (mean 10 mm) and produced adequate degrees of projection of the lower face when accompanied by a modest sliding genioplasty (mean 6.9 mm). Total advancement at the pogonion was a mean of 25.2 mm. In addition, posterior facial height was preserved, and mandibular and occlusal planes were normalized to mean angles of 27 and 10 degrees, respectively. At follow-up, which ranged from 9 to 24 months with a mean of 14.1 months, the mean sagittal relapse at the B point was 1.9 mm. Although heretofore considered unstable and therefore not clinically accepted, maxillomandibular counterclockwise rotation to normalize the occlusal plane rotational deformity provides stable, aesthetically superior results in patients with extreme degrees of mandibular micrognathia. Extended follow-up will be necessary to document long-term stability.

Comparison of Different Methods of Grading a Level Turn Task on a Flight Simulator

NASA Technical Reports Server (NTRS)

Heath, Bruce E.; Crier, tomyka

2003-01-01

With the advancements in the computing power of personal computers, pc-based flight simulators and trainers have opened new avenues in the training of airplane pilots. It may be desirable to have the flight simulator make a quantitative evaluation of the progress of a pilot's training thereby reducing the physical requirement of the flight instructor who must, in turn, watch every flight. In an experiment, University students conducted six different flights, each consisting of two level turns. The flights were three minutes in duration. By evaluating videotapes, two certified flight instructors provided separate letter grades for each turn. These level turns were also evaluated using two other computer based grading methods. One method determined automated grades based on prescribed tolerances in bank angle, airspeed and altitude. The other method used was deviations in altitude and bank angle for performance index and performance grades.

Spontaneous extrusion of a stainless steel glaucoma drainage implant (Ex-PRESS).

PubMed

Tavolato, M; Babighian, S; Galan, A

2006-01-01

To report a case of spontaneous extrusion of a stainless steel glaucoma drainage implant (Ex-PRESS). An Ex-PRESS was implanted under the conjunctiva in a 76-year-old man with primary open-angle glaucoma. Two years after implantation, the Ex-Press extruded spontaneously. Despite this adverse event, there was no increase in intraocular pressure. This is the first report of spontaneous extrusion of an Ex-PRESS device. Implanting the device under a scleral flap should be considered to avoid adverse events such as extrusion or conjunctival erosion.

46 CFR 174.207 - Damaged stability criteria.

Code of Federal Regulations, 2011 CFR

2011-10-01

... sinkage, heel, and trim, must be below the lower edge of an opening through which progressive flooding may... of this subpart; or (v) Side scuttle of the non-opening type. (2) Angle of heel. The angle of heel...

Modified Angle's Classification for Primary Dentition

PubMed Central

Chandranee, Kaushik Narendra; Chandranee, Narendra Jayantilal; Nagpal, Devendra; Lamba, Gagandeep; Choudhari, Purva; Hotwani, Kavita

2017-01-01

Aim: This study aims to propose a modification of Angle's classification for primary dentition and to assess its applicability in children from Central India, Nagpur. Methods: Modification in Angle's classification has been proposed for application in primary dentition. Small roman numbers i/ii/iii are used for primary dentition notation to represent Angle's Class I/II/III molar relationships as in permanent dentition, respectively. To assess applicability of modified Angle's classification a cross-sectional preschool 2000 children population from central India; 3–6 years of age residing in Nagpur metropolitan city of Maharashtra state were selected randomly as per the inclusion and exclusion criteria. Results: Majority 93.35% children were found to have bilateral Class i followed by 2.5% bilateral Class ii and 0.2% bilateral half cusp Class iii molar relationships as per the modified Angle's classification for primary dentition. About 3.75% children had various combinations of Class ii relationships and 0.2% children were having Class iii subdivision relationship. Conclusions: Modification of Angle's classification for application in primary dentition has been proposed. A cross-sectional investigation using new classification revealed various 6.25% Class ii and 0.4% Class iii molar relationships cases in preschool children population in a metropolitan city of Nagpur. Application of the modified Angle's classification to other population groups is warranted to validate its routine application in clinical pediatric dentistry. PMID:29326514

Tuning and predicting the wetting of nanoengineered material surface

NASA Astrophysics Data System (ADS)

Ramiasa-MacGregor, M.; Mierczynska, A.; Sedev, R.; Vasilev, K.

2016-02-01

The wetting of a material can be tuned by changing the roughness on its surface. Recent advances in the field of nanotechnology open exciting opportunities to control macroscopic wetting behaviour. Yet, the benchmark theories used to describe the wettability of macroscopically rough surfaces fail to fully describe the wetting behaviour of systems with topographical features at the nanoscale. To shed light on the events occurring at the nanoscale we have utilised model gradient substrata where surface nanotopography was tailored in a controlled and robust manner. The intrinsic wettability of the coatings was varied from hydrophilic to hydrophobic. The measured water contact angle could not be described by the classical theories. We developed an empirical model that effectively captures the experimental data, and further enables us to predict the wetting of surfaces with nanoscale roughness by considering the physical and chemical properties of the material. The fundamental insights presented here are important for the rational design of advanced materials having tailored surface nanotopography with predictable wettability.The wetting of a material can be tuned by changing the roughness on its surface. Recent advances in the field of nanotechnology open exciting opportunities to control macroscopic wetting behaviour. Yet, the benchmark theories used to describe the wettability of macroscopically rough surfaces fail to fully describe the wetting behaviour of systems with topographical features at the nanoscale. To shed light on the events occurring at the nanoscale we have utilised model gradient substrata where surface nanotopography was tailored in a controlled and robust manner. The intrinsic wettability of the coatings was varied from hydrophilic to hydrophobic. The measured water contact angle could not be described by the classical theories. We developed an empirical model that effectively captures the experimental data, and further enables us to predict the wetting of surfaces with nanoscale roughness by considering the physical and chemical properties of the material. The fundamental insights presented here are important for the rational design of advanced materials having tailored surface nanotopography with predictable wettability. Electronic supplementary information (ESI) available: Detailed characterization of the nanorough substrates and model derivation. See DOI: 10.1039/c5nr08329j

High prevalence of narrow angles among Chinese-American glaucoma and glaucoma suspect patients.

PubMed

Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data were collected for sex, age, race (self-declared), refraction (spherical equivalent), intraocular pressure, gonioscopy, and vertical cup-to-disk ratio. Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade < or = 2 in 3 or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the 2 groups did not differ in terms of sex, refraction, intraocular pressure, or cup-to-disk ratio (all, P > or = 0.071). In a multivariate model including age, sex, and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of sex or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed.

An innovative small angle slot divertor concept for long pulse advanced tokamaks

NASA Astrophysics Data System (ADS)

Guo, Houyang

2017-10-01

A new Small Angle Slot (SAS) divertor is being developed in DIII-D to address the challenge of efficient divertor heat dispersal at the relatively low plasma density required for non-inductive current drive in future advanced tokamaks. SAS features a small incident angle near the plasma strike point on the divertor target plate with a progressively opening slot. SOLPS (B2-Eirene) edge code analysis finds that SAS can achieve strong plasma cooling when the strike point is placed near the small angle target plate in the slot, leading to low electron temperature Te across the entire divertor target. This is enabled by strong coupling between a gas tight slot and directed neutral recycling by the small angle target to enhance neutral buildup near the target. SOLPS analysis reveals a strong correlation between Te and D2 density at the target for various divertor configurations including the flat target, slanted target, and lower single null divertor. The strong correlation suggests that achievement of low Te may reduce essentially to identifying the divertor baffle geometry that achieves the highest target gas density at a given upstream condition. The SAS divertor concept has recently been tested in DIII-D for a range of plasma configurations and conditions with precise control of slot strike point location. In confirmation of SOLPS predictions, a sharp transition is observed when the strike point is moved to the critical outer corner of SAS. A set of Langmuir probes imbedded in SAS show that the Te radial profile, which is peaked at the strike point when it is located away from the SAS corner, becomes low across the target when the strike point is located near the corner. With further increase in density, deep-slot detachment occurs with Te 1 eV, measured by the unique DIII-D divertor Thomson Scattering diagnostic. Work supported by US DOE under DE-FC02-04ER54698.

Layer-by-Layer Evolution of a Two-Dimensional Electron Gas Near an Oxide Interface

NASA Astrophysics Data System (ADS)

Chang, Young Jun; Moreschini, Luca; Bostwick, Aaron; Gaines, Geoffrey A.; Kim, Yong Su; Walter, Andrew L.; Freelon, Byron; Tebano, Antonello; Horn, Karsten; Rotenberg, Eli

2013-09-01

We report the momentum-resolved measurement of a two-dimensional electron gas at the LaTiO3/SrTiO3 interface by angle-resolved photoemission spectroscopy (ARPES). Thanks to an advanced sample preparation technique, the orbital character of the conduction electrons and the electronic correlations can be accessed quantitatively as each unit cell layer is added. We find that all of these quantities change dramatically with distance from the interface. These findings open the way to analogous studies on other heterostructures, which are traditionally a forbidden field for ARPES.

Hypothyroidism as a risk factor for open angle glaucoma: A systematic review and meta-analysis

PubMed Central

Liu, Yue; Zheng, Guangying

2017-01-01

Purpose The relationship between hypothyroidism and primary open angle glaucoma (POAG) has attracted intense interest recently, but the reported results have been controversial. This meta-analysis was carried out to determine the association between hypothyroidism and POAG. Methods The literature was identified from three databases (Web of Science, Embase, and PubMed). The meta-analyses were performed using random-effects models, with results reported as adjusted odds ratios (ORs) with 95% confidence intervals (CI 95%). Results A total of 11 studies meeting the inclusion criteria were included in the final meta-analysis. The pooled OR based on 11 risk estimates showed a statistically significant increased risk of POAG prevalence among individuals with hypothyroidism (OR = 1.64, 95% CI = 1.27–2.13). Substantial heterogeneity among these studies was detected (P < 0.001; I2 = 83.2%). Sub-group analysis revealed that the cohort studies and case–control studies showed a significant association between hypothyroidism and POAG, which was not observed in cross-sectional studies. There was no significant publication bias in this study. Conclusions The findings of this meta-analysis indicate that individuals with hypothyroidism have an increased risk of developing POAG. PMID:29069095

Development of the 1990 Kalapana Flow Field, Kilauea Volcano, Hawaii

USGS Publications Warehouse

Mattox, T.N.; Heliker, C.; Kauahikaua, J.; Hon, K.

1993-01-01

The 1990 Kalapana flow field is a complex patchwork of tube-fed pahoehoe flows erupted from the Kupaianaha vent at a low effusion rate (approximately 3.5 m3/s). These flows accumulated over an 11-month period on the coastal plain of Kilauea Volcano, where the pre-eruption slope angle was less than 2??. the composite field thickened by the addition of new flows to its surface, as well as by inflation of these flows and flows emplaced earlier. Two major flow types were identified during the development of the flow field: large primary flows and smaller breakouts that extruded from inflated primary flows. Primary flows advanced more quickly and covered new land at a much higher rate than breakouts. The cumulative area covered by breakouts exceeded that of primary flows, although breakouts frequently covered areas already buried by recent flows. Lava tubes established within primary flows were longer-lived than those formed within breakouts and were often reoccupied by lava after a brief hiatus in supply; tubes within breakouts were never reoccupied once the supply was interrupted. During intervals of steady supply from the vent, the daily areal coverage by lava in Kalapana was constant, whereas the forward advance of the flows was sporadic. This implies that planimetric area, rather than flow length, provides the best indicator of effusion rate for pahoehoe flow fields that form on lowangle slopes. ?? 1993 Springer-Verlag.

Assessment of morphological and anatomical characteristics of mental foramen using cone beam computed tomography.

PubMed

Goyushov, Samir; Tözüm, Melek Didem; Tözüm, Tolga Fikret

2018-05-25

To determine the shape, position, vertical height, surrounding bone characteristics, and opening angle of mental foramen (MF) using dental cone beam computed tomography (CBCT). A retrospective study was performed on 663 patients. CBCT records analyzed for the shape, position, and surrounding bone measurements of the MF using Simplant 3D software (Hasselt, Belgium). Opening angle of MF was also assessed. Kruskal-Wallis and Mann-Whitney U tests were employed to test significant differences between parameters, genders and ages. All mental foramina were visualized. Regarding location, 49.2% of the MFs were located between first and second premolars, 7.7 distal and 39.7% coincident to the apex of the mandibular second premolar. The mean MF opening angle was 45.4° on the right side, and 45.9° on the left. There were no statistically differences between gender groups with regard to the opening angle degrees. This study may provide useful information about variations in the position, shape and size, angle of mental foramen, which may help the practitioners to perform safer mental nerve blocks and surgical procedures.

Complications and outcomes of primary phacotrabeculectomy with mitomycin C in a multi-ethnic asian population.

PubMed

Chen, David Z; Koh, Victor; Sng, Chelvin; Aquino, Maria C; Chew, Paul

2015-01-01

To determine the occurrence of intraoperative and postoperative complications up to three years after primary phacotrabeculectomy with intraoperative use of Mitomycin C (MMC) in primary open angle (POAG) and primary angle closure glaucoma (PACG) patients, and the effect of postoperative complications on surgical outcome. Retrospective review of 160 consecutive patients with POAG (n = 105) and PACG (n = 55), who underwent primary phacotrabeculectomy with MMC at the National University Hospital, Singapore, from January 1, 2008 to December 31, 2010. Data was collected using a standardized form that included patient demographic information, ocular characteristics and postoperative complications, including hypotony (defined as intraocular pressure < 6 mmHg), shallow anterior chamber (AC) and hyphema. The mean age ± standard deviation (SD) of patients was 68.2 ± 8.2 years. No patient lost light perception during duration of follow-up. 77% of the postoperative complications occurred within the first month only. The commonest complications were hypotony (n = 41, 25.6%), hyphema (n = 16, 10.0%) and shallow AC (n = 16, 10.0%). Five patients (3.1%) required reoperation for their complications. Early hypotony (defined as hypotony < 30 days postoperatively) was an independent risk factor for surgical failure (hazard ratio [HR], 5.1; 95% CI, 1.6-16.2; p = 0.01). Hypotony with another complication was also a risk factor for surgical failure (p < 0.02). Hypotony, hyphema and shallow AC were the commonest postoperative complications in POAG and PACG patients after phacotrabeculectomy with MMC. Most complications were transient and self-limiting. Early hypotony within the first month was a significant risk factor for surgical failure.

Numerical study on the influence of boss cap fins on efficiency of controllable-pitch propeller

NASA Astrophysics Data System (ADS)

Xiong, Ying; Wang, Zhanzhi; Qi, Wanjiang

2013-03-01

Numerical simulation is investigated to disclose how propeller boss cap fins (PBCF) operate utilizing Reynolds-averaged Navier-Stokes (RANS) method. In addition, exploration of the influencing mechanism of PBCF on the open water efficiency of one controllable-pitch propeller is analyzed through the open water characteristic curves, blade surface pressure distribution and hub streamline distribution. On this basis, the influence of parameters including airfoil profile, diameter, axial position of installation and circumferential installation angle on the open water efficiency of the controllable-pitch propeller is investigated. Numerical results show: for the controllable-pitch propeller, the thrust generated is at the optimum when the radius of boss cap fins is 1.5 times of propeller hub with an optimal installation position in the axial direction, and its optimal circumferential installation position is the midpoint of the extension line of the front and back ends of two adjacent propeller roots in the front of fin root. Under these optimal parameters, the gain of open water efficiency of the controllable-pitch propeller with different advance velocity coefficients is greater than 0.01, which accounts for approximately an increase of 1%-5% of open water efficiency.

Modeling contact angle hysteresis of a liquid droplet sitting on a cosine wave-like pattern surface.

PubMed

Promraksa, Arwut; Chen, Li-Jen

2012-10-15

A liquid droplet sitting on a hydrophobic surface with a cosine wave-like square-array pattern in the Wenzel state is simulated by using the Surface Evolver to determine the contact angle. For a fixed drop volume, multiple metastable states are obtained at two different surface roughnesses. Unusual and non-circular shape of the three-phase contact line of a liquid droplet sitting on the model surface is observed due to corrugation and distortion of the contact line by structure of the roughness. The contact angle varies along the contact line for each metastable state. The maximum and minimum contact angles among the multiple metastable states at a fixed viewing angle correspond to the advancing and the receding contact angles, respectively. It is interesting to observe that the advancing/receding contact angles (and contact angle hysteresis) are a function of viewing angle. In addition, the receding (or advancing) contact angles at different viewing angles are determined at different metastable states. The contact angle of minimum energy among the multiple metastable states is defined as the most stable (equilibrium) contact angle. The Wenzel model is not able to describe the contact angle along the three-phase contact line. The contact angle hysteresis at different drop volumes is determined. The number of the metastable states increases with increasing drop volume. Drop volume effect on the contact angles is also discussed. Crown Copyright © 2012. Published by Elsevier Inc. All rights reserved.

Agreement between Gonioscopic Examination and Swept Source Fourier Domain Anterior Segment Optical Coherence Tomography Imaging

PubMed Central

Nguyen, Donna; Minnal, Vandana R.

2016-01-01

Purpose. To evaluate interobserver, intervisit, and interinstrument agreements for gonioscopy and Fourier domain anterior segment optical coherence tomography (FD ASOCT) for classifying open and narrow angle eyes. Methods. Eighty-six eyes with open or narrow anterior chamber angles were included. The superior angle was classified open or narrow by 2 of 5 glaucoma specialists using gonioscopy and imaged by FD ASOCT in the dark. The superior angle of each FD ASOCT image was graded as open or narrow by 2 masked readers. The same procedures were repeated within 6 months. Kappas for interobserver and intervisit agreements for each instrument and interinstrument agreements were calculated. Results. The mean age was 50.9 (±18.4) years. Interobserver agreements were moderate to good for both gonioscopy (0.57 and 0.69) and FD ASOCT (0.58 and 0.75). Intervisit agreements were moderate to excellent for both gonioscopy (0.53 to 0.86) and FD ASOCT (0.57 and 0.85). Interinstrument agreements were fair to good (0.34 to 0.63), with FD ASOCT classifying more angles as narrow than gonioscopy. Conclusions. Both gonioscopy and FD ASOCT examiners were internally consistent with similar interobserver and intervisit agreements for angle classification. Agreement between instruments was fair to good, with FD ASOCT classifying more angles as narrow than gonioscopy. PMID:27990300

Glaucoma anterior chamber morphometry based on optical Scheimpflug images.

PubMed

Alonso, Ruiz Simonato; Ambrósio Junior, Renato; Paranhos Junior, Augusto; Sakata, Lisandro Massanori; Ventura, Marcelo Palis

2010-01-01

To compare the performance of gonioscopy and noncontact morphometry with anterior chamber tomography (High Resolution Pentacam - HR) using optical Scheimpflug images in the evaluation of the anterior chamber angle (ACA). Transversal study. 112 eyes from 74 subjects evaluated at the Glaucoma Department, Fluminense Federal University, underwent gonioscopy and Pentacam HR. Using gonioscopy, the ACA was graded using the Shaffer Classification (SC) by a single experienced examiner masked to the Pentacam HR findings. Narrow angle was determined in eyes in which the posterior trabecular meshwork could not be seen in two or more quadrants on non-indentation gonioscopy (SC Grade 2 or less). Pentacam HR images of the nasal and temporal quadrants were evaluated by custom software to automatically obtain anterior chamber measurements, such as: anterior chamber angle (ACA), anterior chamber volume (ACV) and anterior chamber depth (ACD). Based on gonioscopy results, 74 (60.07%) eyes of patients classified as open-angle (SC 3 and 4) and 38 (33.93%) eyes of patients classified as narrow-angle (SC 1 and 2). Noncontact morphometry with Scheimpflug images revealed a mean ACA of 39.20 ± 5.31 degrees for open-angle and 21.18 ± 7.98 degrees for narrow-angle. The open-angle group showed significant greater ACV and ACD values when compared to narrow-angle group (ACV of 193 ± 36 mm³ vs. 90 ± 25 mm³, respectively, p<0.001; and ACD of 3,09 ± 0,42 mm vs. 1,55 ± 0,64 mm, respectively, p<0.0001.). In screening eyes with open-angle and narrow-angle with the Pentacam ACA of 20º (SC Grade 2) using the ROC curves, the analysis showed 52.6% of sensitivity and 100% of specificity. The Pentacam showed ability in detecting eyes at risk for angle closure analyzing ACV and ACD.

Advancing Teacher Technology Education Using Open-Ended Learning Environments as Research and Training Platforms

ERIC Educational Resources Information Center

Poitras, Eric; Doleck, Tenzin; Huang, Lingyun; Li, Shan; Lajoie, Susanne

2017-01-01

A primary concern of teacher technology education is for pre-service teachers to develop a sophisticated mental model of the affordances of technology that facilitates both teaching and learning with technology. One of the main obstacles to developing the requisite technological pedagogical content knowledge is the inherent challenge faced by…

Abstract ID: 176 Geant4 implementation of inter-atomic interference effect in small-angle coherent X-ray scattering for materials of medical interest.

PubMed

Paternò, Gianfranco; Cardarelli, Paolo; Contillo, Adriano; Gambaccini, Mauro; Taibi, Angelo

2018-01-01

Advanced applications of digital mammography such as dual-energy and tomosynthesis require multiple exposures and thus deliver higher dose compared to standard mammograms. A straightforward manner to reduce patient dose without affecting image quality would be removal of the anti-scatter grid, provided that the involved reconstruction algorithms are able to take the scatter figure into account [1]. Monte Carlo simulations are very well suited for the calculation of X-ray scatter distribution and can be used to integrate such information within the reconstruction software. Geant4 is an open source C++ particle tracking code widely used in several physical fields, including medical physics [2,3]. However, the coherent scattering cross section used by the standard Geant4 code does not take into account the influence of molecular interference. According to the independent atomic scattering approximation (the so-called free-atom model), coherent radiation is indistinguishable from primary radiation because its angular distribution is peaked in the forward direction. Since interference effects occur between x-rays scattered by neighbouring atoms in matter, it was shown experimentally that the scatter distribution is affected by the molecular structure of the target, even in amorphous materials. The most important consequence is that the coherent scatter distribution is not peaked in the forward direction, and the position of the maximum is strongly material-dependent [4]. In this contribution, we present the implementation of a method to take into account inter-atomic interference in small-angle coherent scattering in Geant4, including a dedicated data set of suitable molecular form factor values for several materials of clinical interest. Furthermore, we present scatter images of simple geometric phantoms in which the Rayleigh contribution is rigorously evaluated. Copyright © 2017.

Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush.

PubMed

Groth, Sylvia L; Greider, Kelsi L; Sponsel, William Eric

2015-01-01

To assess the utility of viscoelastic injection to induce bleb expansion and decrease intraocular pressure (IOP) in eyes with encapsulated glaucoma tube shunt blebs. Case series. Forty-three glaucomatous eyes, including 13 eyes with congenital, 13 uveitic, 5 neovascular, 5 open angle, 4 narrow angle and 3 traumatic glaucomas. Methods, interventions or testing: All patients underwent viscoelastic flush procedure. A pre-bent 27 or 30-gauge cannula was passed through a 25-gauge paracentesis, advanced over the iris across the anterior chamber, and insinuated into the tube shunt lumen. Once the cannula was firmly lodged in position, 0.45 to 0.85 ml of viscoelastic was injected to hyperinflate the bleb. Paired t-tests were performed comparing preoperative IOP and number of medications used preoperatively vs levels measured at 1, 6, 12, 18 and 24 months. Intraocular pressure was reduced from a mean preoperative level of 26.0 ± 1.2 (sem) mm Hg to 15.8 ± 1.0 at 1 month, remaining stable thereafter at each 6-month interval with 15.1 ± 1.1 mm Hg at 24 months (p < 0.0001). Medication use did not vary significantly from baseline. Pressure remained < 21 mm Hg after 2 years in 85% of eyes cannulated within 1 year of primary tube shunt implantation (n = 23), and in 62% of eyes cannulated more than 1 year after tube shunt placement (n = 20). Tube shunt expansion with bolus viscoelastic flush successfully restored encapsulated bleb function, providing a substantial (~10 mm Hg) IOP decrease into the mid-normal pressure range. This persisted in the majority of treated eyes for the entire study period. How to cite this article: Groth SL, Greider KL, Sponsel WE. Utility of Operative Glaucoma Tube Shunt Viscoelastic Bolus Flush. J Curr Glaucoma Pract 2015;9(3):73-76.

Peripapillary schisis in open-angle glaucoma.

PubMed

Dhingra, N; Manoharan, R; Gill, S; Nagar, M

2017-03-01

PurposeTo report clinical features, topographic findings and outcome of 10 eyes with peripapillary schisis in open-angle glaucoma.Patients and methodsA retrospective review of patients with open-angle glaucoma who were noted to have peripapillary schisis on optical coherence tomography (OCT) were included. Serial peripapillary and macula infrared and OCT images, visual acuity, visual fields, and schisis appearance were reviewed.ResultsTen eyes of nine patients with open-angle glaucoma were detected to have the presence of peripapillary schisis. Nerve fibre layer schisis was detected in all eyes and one eye had an associated macular schisis. None of the eyes had an acquired pit of the optic nerve or pathological myopia. The mean intraocular pressures at detection was 18.3±4.3 mm Hg and the schisis resolved in four eyes after a mean follow-up of 21.2±8.8 months. Visual field worsening was noted in 4 of the 10 eyes and the resolution of schisis resulted in significant reduction in the retinal nerve fibre layer (RNFL) thickness.ConclusionsPeripapillary schisis detected during the normal course of open-angle glaucoma can resolve spontaneously and rarely involves the macula. Its resolution leads to reduction in RNFL thickness; therefore, caution is advised while interpreting serial scans.

Scanning electron microscopy of the trabecular meshwork: understanding the pathogenesis of primary angle closure glaucoma.

PubMed

Sihota, Ramanjit; Goyal, Amita; Kaur, Jasbir; Gupta, Viney; Nag, Tapas C

2012-01-01

To study ultrastructural changes of the trabecular meshwork in acute and chronic primary angle closure glaucoma (PACG) and primary open angle glaucoma (POAG) eyes by scanning electron microscopy. Twenty-one trabecular meshwork surgical specimens from consecutive glaucomatous eyes after a trabeculectomy and five postmortem corneoscleral specimens were fixed immediately in Karnovsky solution. The tissues were washed in 0.1 M phosphate buffer saline, post-fixed in 1% osmium tetraoxide, dehydrated in acetone series (30-100%), dried and mounted. Normal trabecular tissue showed well-defined, thin, cylindrical uveal trabecular beams with many large spaces, overlying flatter corneoscleral beams and numerous smaller spaces. In acute PACG eyes, the trabecular meshwork showed grossly swollen, irregular trabecular endothelial cells with intercellular and occasional basal separation with few spaces. Numerous activated macrophages, leucocytes and amorphous debris were present. Chronic PACG eyes had a few, thickened posterior uveal trabecular beams visible. A homogenous deposit covered the anterior uveal trabeculae and spaces. Converging, fan-shaped trabecular beam configuration corresponded to gonioscopic areas of peripheral anterior synechiae. In POAG eyes, anterior uveal trabecular beams were thin and strap-like, while those posteriorly were wide, with a homogenous deposit covering and bridging intertrabecular spaces, especially posteriorly. Underlying corneoscleral trabecular layers and spaces were visualized in some areas. In acute PACG a marked edema of the endothelium probably contributes for the acute and marked intraocular pressure (IOP) elevation. Chronically raised IOP in chronic PACG and POAG probably results, at least in part, from decreased aqueous outflow secondary to widening and fusion of adjacent trabecular beams, together with the homogenous deposit enmeshing trabecular beams and spaces.

The long-term outcomes of four alternative treatment strategies for primary open-angle glaucoma.

PubMed

van Gestel, Aukje; Webers, Carroll A; Severens, Johan L; Beckers, Henny J; Jansonius, Nomdo M; Hendrikse, Fred; Schouten, Jan S

2012-02-01

To evaluate the long-term effects and costs of four treatment strategies for primary open-angle glaucoma compared to usual care. Cost-effectiveness analyses with a lifelong horizon were made from a societal perspective. Data were generated with a patient-level model based on discrete event simulation. The model structure and parameter estimates were based on literature, particularly clinical studies on the natural course of glaucoma and the effect of treatment. We simulated heterogeneous cohorts of 3000 patients and explored the impact of uncertainty with sensitivity analyses. The incremental cost-effectiveness ratio (ICER) of initial treatment with a prostaglandin analogue compared with a β-blocker was €12.931 per quality-adjusted life year (QALY) gained. A low initial target pressure (15 mmHg) resulted in 0.115 QALYs gained and €1550 saved compared to a gradual decrease from 21 to 15 mmHg upon progression. Visual field (VF) measurements every 6 rather than 12 months lead to health gains at increased costs (ICER €173,486 per QALY gained), whereas measurements every 24 months lead to health losses at reduced costs (ICER €21,516 per QALY lost). All treatment strategies were dominant over 'withholding treatment'. From a cost-effectiveness point of view, it seems advantageous to aim for a low intraocular pressure in all glaucoma patients. The feasibility of this strategy should therefore be investigated. Additionally, the cost-effectiveness outcomes of initiating monotherapy with a prostaglandin analogue and reducing the frequency of VF testing may be acceptable. © 2012 The Authors. Acta Ophthalmologica © 2012 Acta Ophthalmologica Scandinavica Foundation.

Diagnostic Capability of Peripapillary Retinal Volume Measurements in Glaucoma.

PubMed

Simavli, Huseyin; Poon, Linda Yi-Chieh; Que, Christian J; Liu, Yingna; Akduman, Mustafa; Tsikata, Edem; de Boer, Johannes F; Chen, Teresa C

2017-06-01

To determine the diagnostic capability of spectral domain optical coherence tomography peripapillary retinal volume (RV) measurements. A total of 156 patients, 89 primary open-angle glaucoma and 67 normal subjects, were recruited. Spectral domain optical coherence tomography peripapillary RV was calculated for 4 quadrants using 3 annuli of varying scan circle diameters: outer circumpapillary annuli of circular grids 1, 2, and 3 (OCA1, OCA2, OCA3). Area under the receiver operating characteristic curves and pairwise comparisons of receiver operating characteristic (ROC) curves were performed to determine which quadrants were best for diagnosing primary open-angle glaucoma. The pairwise comparisons of the best ROC curves for RV and retinal nerve fiber layer (RNFL) were performed. The artifact rates were analyzed. Pairwise comparisons showed that the smaller annuli OCA1 and OCA2 had better diagnostic performance than the largest annulus OCA3 (P<0.05 for all quadrants). OCA1 and OCA2 had similar diagnostic performance, except for the inferior quadrant which was better for OCA1 (P=0.0033). The pairwise comparisons of the best ROC curves for RV and RNFL were not statistically significant. RV measurements had lower rates of artifacts at 7.4% while RNFL measurements had higher rates at 42.9%. Peripapillary RV measurements have excellent ability for diagnosing not only glaucoma patients but also a subset of early glaucoma patients. The inferior quadrant of peripapillary annulus OCA1 demonstrated the best diagnostic capability for both glaucoma and early glaucoma. The diagnostic ability of RV is comparable with that of RNFL parameters in glaucoma but with lower artifact rates.

New insights into the genetics of primary open-angle glaucoma based on meta-analyses of intraocular pressure and optic disc characteristics

PubMed Central

Springelkamp, Henriët; Iglesias, Adriana I.; Mishra, Aniket; Höhn, René; Wojciechowski, Robert; Khawaja, Anthony P.; Nag, Abhishek; Wang, Ya Xing; Wang, Jie Jin; Cuellar-Partida, Gabriel; Gibson, Jane; Bailey, Jessica N. Cooke; Vithana, Eranga N.; Gharahkhani, Puya; Boutin, Thibaud; Ramdas, Wishal D.; Zeller, Tanja; Luben, Robert N.; Yonova-Doing, Ekaterina; Viswanathan, Ananth C.; Yazar, Seyhan; Cree, Angela J.; Haines, Jonathan L.; Koh, Jia Yu; Souzeau, Emmanuelle; Wilson, James F.; Amin, Najaf; Müller, Christian; Venturini, Cristina; Kearns, Lisa S.; Kang, Jae Hee; Tham, Yih Chung; Zhou, Tiger; van Leeuwen, Elisabeth M.; Nickels, Stefan; Sanfilippo, Paul; Liao, Jiemin; van der Linde, Herma; Zhao, Wanting; van Koolwijk, Leonieke M.E.; Zheng, Li; Rivadeneira, Fernando; Baskaran, Mani; van der Lee, Sven J.; Perera, Shamira; de Jong, Paulus T.V.M.; Oostra, Ben A.; Uitterlinden, André G.; Fan, Qiao; Hofman, Albert; Tai, E-Shyong; Vingerling, Johannes R.; Sim, Xueling; Wolfs, Roger C.W.; Teo, Yik Ying; Lemij, Hans G.; Khor, Chiea Chuen; Willemsen, Rob; Lackner, Karl J.; Aung, Tin; Jansonius, Nomdo M.; Montgomery, Grant; Wild, Philipp S.; Young, Terri L.; Burdon, Kathryn P.; Hysi, Pirro G.; Pasquale, Louis R.; Wong, Tien Yin; Klaver, Caroline C.W.; Hewitt, Alex W.; Jonas, Jost B.; Mitchell, Paul; Lotery, Andrew J.; Foster, Paul J.; Vitart, Veronique; Pfeiffer, Norbert; Craig, Jamie E.; Mackey, David A.; Hammond, Christopher J.; Wiggs, Janey L.; Cheng, Ching-Yu; van Duijn, Cornelia M.; MacGregor, Stuart

2017-01-01

Abstract Primary open-angle glaucoma (POAG), the most common optic neuropathy, is a heritable disease. Siblings of POAG cases have a ten-fold increased risk of developing the disease. Intraocular pressure (IOP) and optic nerve head characteristics are used clinically to predict POAG risk. We conducted a genome-wide association meta-analysis of IOP and optic disc parameters and validated our findings in multiple sets of POAG cases and controls. Using imputation to the 1000 genomes (1000G) reference set, we identified 9 new genomic regions associated with vertical cup-disc ratio (VCDR) and 1 new region associated with IOP. Additionally, we found 5 novel loci for optic nerve cup area and 6 for disc area. Previously it was assumed that genetic variation influenced POAG either through IOP or via changes to the optic nerve head; here we present evidence that some genomic regions affect both IOP and the disc parameters. We characterized the effect of the novel loci through pathway analysis and found that pathways involved are not entirely distinct as assumed so far. Further, we identified a novel association between CDKN1A and POAG. Using a zebrafish model we show that six6b (associated with POAG and optic nerve head variation) alters the expression of cdkn1a. In summary, we have identified several novel genes influencing the major clinical risk predictors of POAG and showed that genetic variation in CDKN1A is important in POAG risk. PMID:28073927

Do non-communicable diseases such as hypertension and diabetes associate with primary open-angle glaucoma? Insights from a case-control study in Nepal.

PubMed

Shakya-Vaidya, Suraj; Aryal, Umesh Raj; Upadhyay, Madan; Krettek, Alexandra

2013-11-04

Non-communicable diseases (NCDs) such as hypertension and diabetes are rapidly emerging public health problems worldwide, and they associate with primary open-angle glaucoma (POAG). POAG is the most common cause of irreversible blindness. The most effective ways to prevent glaucoma blindness involve identifying high-risk populations and conducting routine screening for early case detection. This study investigated whether POAG associates with hypertension and diabetes in a Nepalese population. To explore the history of systemic illness, our hospital-based case-control study used non-random consecutive sampling in the general eye clinics in three hospitals across Nepal to enroll patients newly diagnosed with POAG and controls without POAG. The study protocol included history taking, ocular examination, and interviews with 173 POAG cases and 510 controls. Data analysis comprised descriptive and inferential statistics. Descriptive statistics computed the percentage, mean, and standard deviation (SD); inferential statistics used McNemar's test to measure associations between diseases. POAG affected males more frequently than females. The odds of members of the Gurung ethnic group having POAG were 2.05 times higher than for other ethnic groups. Hypertension and diabetes were strongly associated with POAG. The overall odds of POAG increased 2.72-fold among hypertensive and 3.50-fold among diabetic patients. POAG associates significantly with hypertension and diabetes in Nepal. Thus, periodic glaucoma screening for hypertension and diabetes patients in addition to opportunistic screening at eye clinics may aid in detecting more POAG cases at an early stage and hence in reducing avoidable blindness.

Level of agreement among Latin American glaucoma subspecialists on the diagnosis and treatment of glaucoma: results of an online survey.

PubMed

Grigera, Daniel E; Mello, Paulo Augusto Arruda; Barbosa, Wilma Lelis; Casiraghi, Javier Fernando; Grossmann, Rodolfo Perez; Peyret, Alejo

2013-01-01

The aim of this research was to assess the level of agreement among glaucoma experts in Latin America on key practices related to treatment and diagnosis of glaucoma. An online questionnaire was sent to a multinational panel of glaucoma experts. The questionnaire contained 107 statements on the medical treatment (Part 1) and diagnosis (Part 2) of glaucoma, and was developed in Spanish and translated into English. Agreement was defined as >70% of respondents. Fifty participants from 14 countries completed the questionnaire. For the medical treatment of glaucoma, nearly all respondents (98% or greater) confirmed that medical treatment as first-line therapy is preferred to surgery, prostaglandin analogs are the medication of first choice for primary open-angle glaucoma (POAG), longitudinal monitoring of efficacy should include intraocular pressure, structural and functional status, as well as if patients' quality of life is impaired by the high cost of medication. For the diagnosis of glaucoma section, all respondents confirmed that, after initial examination, gonioscopy should be repeated over time, standard automated perimetry is the most important functional examination for diagnosis and monitoring of primary open-angle glaucoma, central corneal thickness is important in assessment of glaucoma, and computerized imaging tests help in clinical evaluation of optic disc. This survey shows a high level of agreement on most aspects of glaucoma diagnosis and treatment among Latin American glaucoma experts. Areas of disagreement highlight the need for further evidence or education. These findings will be useful for guiding future efforts to optimize glaucoma practice by clinicians in Latin America.

Histological findings of failed gold micro shunts in primary open-angle glaucoma.

PubMed

Agnifili, Luca; Costagliola, Ciro; Figus, Michele; Iezzi, Giovanna; Piattelli, Adriano; Carpineto, Paolo; Mastropasqua, Rodolfo; Nardi, Marco; Mastropasqua, Leonardo

2012-01-01

To describe the histological features of failed gold micro shunts (GMS) in unsuccessful implantations for refractory primary open-angle glaucoma (POAG). This was an interventional case series study. Five eyes of five glaucomatous patients with unsuccessful GMS implantation underwent shunt removal. Each device was sectioned into three portions: proximal or anterior chamber (AC) portion, middle or scleral portion and distal or suprachoroidal (SC) portion. The histological analysis was performed throughout the whole extent of the shunt, describing both the inner spaces and the outer surface. At the moment of removal all devices were correctly located into the SC space and in AC, with the exception of a case presenting corneal endothelial contact. The mean intra-ocular pressure before GMS removal was 30.4 ± 5.3 mmHg, and the mean time of GMS removal after implantation was 6.8 ± 2.5 months. No significant histological differences were documented among the five analyzed devices. The main feature was the presence of a thick connective capsule-like reaction surrounding both the proximal and distal ends and invading the posterior and anterior grid holes, whereas a more loosely arranged connective tissue was observed within the inner channels. Signs of surface fibrosis of the middle-scleral portion and inflammatory cell infiltration of the device were not documented in any of the cases. Failed GMS implantations presented connective tissue filling all the inner spaces and creating a thick fibrotic capsule surrounding the ends of the device. This modification isolated the GMS from the AC and SC space, impeding aqueous flows throughout the shunt.

[Macular choroidal blood flow in concurrent age-related macular degeneration and primary open-angle glaucoma].

PubMed

Panova, I E; Ermak, E M; Shaimova, T A; Shaimova, V A

2016-01-01

Ocular circulation disorders are an important factor in the development of primary open-angle glaucoma (POAG) and age-related macular degeneration (AMD). To date, however, there have been no studies on choroidal blood flow peculiarities in case of concurrent AMD and POAG. to determine distinctive features of choroidal blood flow characteristic of concurrent AMD and POAG and to assess their role in disease pathogenesis. Macular choroidal blood flow, including blood supply, was assessed in 54 patients (102 eyes) by means of Doppler ultrasound. Three groups were formed: group 1 - 38 eyes with both AMD and POAG; group 2 - 41 eyes with AMD and no signs of optic nerve pathology; and group 3 - 23 eyes with POAG and no signs of AMD. Groups 1 and 2 were subdivided into two subgroups each: А - atrophic AMD and B - macular drusen. The mean patient age was 78.7±8.4 years. The following parameters of choroidal blood flow were of interest: peak systolic velocity (Vps), end diastolic velocity (Ved), time-averaged maximum velocity (Vtamax), and resistance index (RI). Groups 1, 3, and 2A had an evident choroidal hypoperfusion in the macular area (decreased Vtamax) with uncompensated perfusion deficit, despite autoregulation efforts (decreased Vps, Ved, decreased or normal RI). Group 2B demonstrated a significantly higher rate of choroidal hyperperfusion (increased Vps, Ved, Vtamax, and RI). Concurrent AMD and POAG are notable for choroidal hypoperfusion in the macular area that leads to inadequate trophism of the neurosensory retina and can aggravate the course of AMD contributing to progression of its atrophic form.

Unaltered myocilin expression in the blood of primary open angle glaucoma patients

PubMed Central

Azad, Taif Anwar; Spaeth, George L.; Myers, Jonathan; Katz, L. Jay; Moster, Marlene; Bosley, Thomas M.

2012-01-01

Purpose To investigate the expression of the myocilin gene (MYOC) in the blood of primary open angle glaucoma (POAG) patients to determine if altered systemic expression is playing a role. Methods Patients (n=47) were eligible for inclusion if they met standard clinical criteria for POAG. Control subjects (n=27) were recruited who were free from glaucoma by examination. RNA was extracted from leukocytes of patients and controls and converted to cDNA by reverse transcriptase enzyme, and quantitative PCR was used to assess expression levels of MYOC and the house keeping gene β-globulin (HBB). The ratio of MYOC expression to HBB expression for POAG patients was compared to that of controls and to clinical characteristics of POAG patients. Results Mean gene expression values were statistically similar in POAG patients and controls for both MYOC (p≤0.55) and HBB (p≤0.48). MYOC/HBB ratios were also statistically indistinguishable between POAG patients and controls (p≤0.90). MYOC/HBB ratios were not significantly associated with age, sex, or ethnicity of patients within the POAG group. Similarly, MYOC/HBB ratios were not significantly associated with clinical parameters related to POAG severity, including maximum intraocular pressure, vertical cup-to-disk ratio, static perimetry mean deviation, or static perimetry pattern standard deviation. Conclusions MYOC expression is not altered in the blood of POAG patients, unlike MYOC expression in trabecular meshwork (TM) cultures. These results suggests that MYOC expression is not altered systemically but rather that MYOC expression may contribute to POAG pathogenesis in specific tissues such as TM. PMID:22550394

Rates of glaucoma medication utilization among persons with primary open-angle glaucoma, 1992 to 2002.

PubMed

Stein, Joshua D; Ayyagari, Padmaja; Sloan, Frank A; Lee, Paul P

2008-08-01

To determine the percentage of Medicare beneficiaries with primary open-angle glaucoma (POAG) treated medically or surgically, utilization rates for each major class of glaucoma medication, and factors influencing treatment. Longitudinal observational study using data from the Medicare Current Beneficiary Survey (MCBS). Persons age 65 and older with POAG, 1992 to 2002 (N = 6446). By using MCBS data merged with Medicare claims, rates of medical and surgical treatment for participants with POAG were determined. Logistic analysis was used to assess factors associated with use of care. Receipt/nonreceipt of medical or surgical therapy in a year and rates of drug utilization by class and of surgery by type among persons who did not receive medical therapy in a year. On average from 1992 to 2002, 27.4% of persons diagnosed with POAG received no medical or surgical treatment. Rates of nonuse increased by 3% annually (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.02-1.05). Beneficiaries with Medicaid were 43% more likely not to receive care for POAG in a year (OR, 1.43; 95% CI, 1.20-1.70). Hispanic, Asian, and beneficiaries of other race/ethnicity were less likely to receive treatment than were whites. Use of beta-blockers and miotics decreased, but utilization rates increased substantially for alpha-agonists, combination beta-blocker-carbonic anhydrase inhibitors, and especially prostaglandin analogs. Despite availability of more efficacious glaucoma medication classes with few side effects and findings of clinical trials underscoring the importance of intraocular pressure reduction in POAG patients, many patients with POAG continue to go untreated.

Comparison of the diagnostic ability of Moorfield’s regression analysis and glaucoma probability score using Heidelberg retinal tomograph III in eyes with primary open angle glaucoma

PubMed Central

Jindal, Shveta; Dada, Tanuj; Sreenivas, V; Gupta, Viney; Sihota, Ramanjit; Panda, Anita

2010-01-01

Purpose: To compare the diagnostic performance of the Heidelberg retinal tomograph (HRT) glaucoma probability score (GPS) with that of Moorfield’s regression analysis (MRA). Materials and Methods: The study included 50 eyes of normal subjects and 50 eyes of subjects with early-to-moderate primary open angle glaucoma. Images were obtained by using HRT version 3.0. Results: The agreement coefficient (weighted k) for the overall MRA and GPS classification was 0.216 (95% CI: 0.119 – 0.315). The sensitivity and specificity were evaluated using the most specific (borderline results included as test negatives) and least specific criteria (borderline results included as test positives). The MRA sensitivity and specificity were 30.61 and 98% (most specific) and 57.14 and 98% (least specific). The GPS sensitivity and specificity were 81.63 and 73.47% (most specific) and 95.92 and 34.69% (least specific). The MRA gave a higher positive likelihood ratio (28.57 vs. 3.08) and the GPS gave a higher negative likelihood ratio (0.25 vs. 0.44).The sensitivity increased with increasing disc size for both MRA and GPS. Conclusions: There was a poor agreement between the overall MRA and GPS classifications. GPS tended to have higher sensitivities, lower specificities, and lower likelihood ratios than the MRA. The disc size should be taken into consideration when interpreting the results of HRT, as both the GPS and MRA showed decreased sensitivity for smaller discs and the GPS showed decreased specificity for larger discs. PMID:20952832

Retinal adaptation abnormalities in primary open-angle glaucoma.

PubMed

Dul, Mitchell; Ennis, Robert; Radner, Shira; Lee, Barry; Zaidi, Qasim

2015-01-22

Dynamic color and brightness adaptation are crucial for visual functioning. The effects of glaucoma on retinal ganglion cells (RGCs) could compromise these functions. We have previously used slow dynamic changes of light at moderate intensities to measure the speed and magnitude of subtractive adaptation in RGCs. We used the same procedure to test if RGC abnormalities cause slower and weaker adaptation for patients with glaucoma when compared to age-similar controls. We assessed adaptation deficits in specific classes of RGCs by testing along the three cardinal color axes that isolate konio, parvo, and magno RGCs. For one eye each of 10 primary open-angle glaucoma patients and their age-similar controls, we measured the speed and magnitude of adapting to 1/32 Hz color modulations along the three cardinal axes, at central fixation and 8° superior, inferior, nasal, and temporal to fixation. In all 15 comparisons (5 locations × 3 color axes), average adaptation was slower and weaker for glaucoma patients than for controls. Adaptation developed slower at central targets than at 8° eccentricities for controls, but not for patients. Adaptation speed and magnitude differed between affected and control eyes even at retinal locations showing no visual field loss with clinical perimetry. Neural adaptation is weaker in glaucoma patients for all three classes of RGCs. Since adaptation abnormalities are manifested even at retinal locations not exhibiting a visual field loss, this novel form of assessment may offer a functional insight into glaucoma and an early diagnosis tool. Copyright 2015 The Association for Research in Vision and Ophthalmology, Inc.

Dependence of diameters and oxygen saturation of retinal vessels on visual field damage and age in primary open-angle glaucoma.

PubMed

Ramm, Lisa; Jentsch, Susanne; Peters, Sven; Sauer, Lydia; Augsten, Regine; Hammer, Martin

2016-05-01

To investigate the interrelationship between the oxygen supply of the retina and its regulation with the severity of primary open-angle glaucoma (POAG). Central retinal artery (CRAE) and vein (CRVE) diameters and oxygen saturation of peripapillary retinal vessels in 41 patients suffering from POAG (64.1 ± 12.9 years) and 40 healthy volunteers (63.6 ± 14.1 years) were measured using the retinal vessel analyzer. All measures were taken before and during flicker light stimulation. The mean retinal nerve fiber layer thickness (RNFLT) was determined by OCT and the visual field mean defect (MD) was identified using perimetry. In glaucoma patients, CRAE (r = -0.48 p = 0.002) and CRVE (r = -0.394 p = 0.014) at baseline were inversely related to MD, while arterial and venous oxygen saturation showed no significant dependence on the severity of the damage. However, the flicker light-induced change in arterio-venous difference in oxygen saturation was correlated with the MD (r = 0.358 p = 0.027). The diameters of arteries and veins at baseline decreased with reduction of the mean RNFLT (arteries: r = 0.718 p < 0.001; veins: r = 0.685 p < 0.001). Vessel diameters showed a strong correlation with RNFLT and MD. This, as well as the reduction of stimulation-induced change in arterio-venous oxygen saturation difference with visual field loss, may be explained by a reduction of the retinal metabolic demand with progressive loss of neuronal tissue in glaucoma. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Change in Visual Field Progression Following Treatment Escalation in Primary Open-angle Glaucoma.

PubMed

Aptel, Florent; Bron, Alain M; Lachkar, Yves; Schweitzer, Cédric

2017-10-01

To evaluate the effect of treatment escalation on the rate of visual field progression in patients with primary open-angle glaucoma (POAG). Multicenter database study. We reviewed the electronic records of 171 patients with POAG under medical hypotensive treatment who underwent 5 consecutive visits 6 months apart before and after medical treatment escalation or additive laser trabeculoplasty. We calculated the rate of visual field progression (mean deviation change per year) before and after treatment escalation. The mean duration of follow-up was 5.1±0.5 years and the mean number of visual field examinations was 10.2±0.2. In 139 eyes with medical treatment escalation, the rate of progression was significantly reduced [from -0.57 to -0.29 dB/y; P=0.022; intraocular pressure (IOP) reduction 11.1%]. In detail, the rate of progression was significantly reduced after escalation from mono to dual therapy, dual to triple therapy, and from mono to triple therapy (-0.35 to -0.24 dB/y, P=0.018; -1.01 to -0.48 dB/y, P=0.038; -1.04 to -0.35 dB/y, P=0.020, respectively). In 32 eyes with additive laser trabeculoplasty, the rate of progression was significantly reduced (-0.60 to -0.24 dB/y; P=0.014; IOP reduction 9.4%). Medical treatment escalation or additive laser trabeculoplasty significantly reduced the rate of visual field progression in POAG. Larger IOP reduction has a greater probability of reducing glaucoma progression.

Relationship between progression of visual field defect and intraocular pressure in primary open-angle glaucoma.

PubMed

Naito, Tomoko; Yoshikawa, Keiji; Mizoue, Shiro; Nanno, Mami; Kimura, Tairo; Suzumura, Hirotaka; Shiraga, Fumio

2015-01-01

To analyze the relationship between intraocular pressure (IOP) and the progression of visual field defects in Japanese primary open-angle glaucoma (POAG) and normal-tension glaucoma (NTG) patients. The subjects of the study were patients undergoing treatment for POAG or NTG who had performed visual field tests at least ten times with a Humphrey field analyzer (Swedish interactive thresholding algorithm standard, C30-2 program). The progression of visual field defects was defined by a significantly negative value of the mean deviation slope at the final visual field test during the follow-up period. The relationships between the progression of visual field defects and IOP, as well as other clinical factors, were retrospectively analyzed. A total of 156 eyes of 156 patients were included in the analysis. Significant progression of visual field defects was observed in 70 eyes of 70 patients (44.9%), while no significant progression was evident in 86 eyes of 86 patients (55.1%). The eyes with visual field defect progression had significantly lower baseline IOP (P<0.05), as well as significantly lower IOP reduction rate (P<0.01). The standard deviation of IOP values during follow-up was significantly greater in the eyes with visual field defect progression than in eyes without (P<0.05). Reducing IOP is thought to be useful for Japanese POAG or NTG patients to suppress the progression of visual field defects. In NTG, IOP management should take into account not only achieving the target IOP, but also minimizing the fluctuation of IOP during follow-up period.

Changes in the retrobulbar arterial circulation after decrease of elevated intraocular pressue in patients with primary open angle glaucoma.

PubMed

Marjanović, Ivan; Sundić, Ana; Mijajlović, Milija; Covicković-Sternić, Nadezda; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija; Knezević, Miroslav

2011-01-01

An altered perfusion of the optic nerve head has been proposed as a pathogenic factor in glaucoma. To evaluate changes of haemodynamic parameters in the retrobulbar arterial circulation after a decrease of elevated intraocular pressure (IOP) in patients with primary open angle glaucoma (POAG). Twenty-six patients were examined, 14 men and 12 women, 21 up to 50 years old and 5 below, all with previously diagnosed and treated POAG, and all examined at the Eye Clinic, Clinical Centre of Serbia. IOP was measured both with a Goldmann aplanation tonometer and dynamic contour tonometer. Central corneal thickness was measured with ultrasound pachymeter. Imaging of the retrobulbar arterial circulation by colour Doppler was performed at the Neurology Clinic, Clinical Centre of Serbia. It involved measuring of haemodynamic parameters of the ophthalmic artery, central retinal artery, and posterior ciliary arteries. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) and pulsatility index (PI) were calculated. Haemodynamic arterial parameters PSV and EDV in the ophthalmic and central retinal artery after decrease of IOP were lower, while RI and PI were higher. In the posterior ciliary arteries PSV, EDV and PI were lower, and RI was higher. Changes of the retrobulbar arterial circulation after elevated LOP in POAG patients are important for approach and treatment, while the role of vascular factors in the supplement of the optic disc neuroretinal rim could be a key for progression backlash of glaucoma and the radix of neuroprotection.

Using Genetic Mouse Models to Gain Insight into Glaucoma: Past Results and Future Possibilities

PubMed Central

Fernandes, Kimberly A.; Harder, Jeffrey M.; Williams, Pete A.; Rausch, Rebecca L.; Kiernan, Amy E.; Nair, K. Saidas; Anderson, Michael G.; John, Simon W.; Howell, Gareth R.; Libby, Richard T.

2015-01-01

While all forms of glaucoma are characterized by a specific pattern of retinal ganglion cell death, they are clinically divided into several distinct subclasses, including normal tension glaucoma, primary open angle glaucoma, congenital glaucoma, and secondary glaucoma. For each type of glaucoma there are likely numerous molecular pathways that control susceptibility to the disease. Given this complexity, a single animal model will never precisely model all aspects of all the different types of human glaucoma. Therefore, multiple animal models have been utilized to study glaucoma but more are needed. Because of the powerful genetic tools available to use in the laboratory mouse, it has proven to be a highly useful mammalian system for studying the pathophysiology of human disease. The similarity between human and mouse eyes coupled with the ability to use a combination of advanced cell biological and genetic tools in mice have led to a large increase in the number of studies using mice to model specific glaucoma phenotypes. Over the last decade, numerous new mouse models and genetic tools have emerged, providing important insight into the cell biology and genetics of glaucoma. In this review, we describe available mouse genetic models that can be used to study glaucoma-relevant disease/pathobiology. Furthermore, we discuss how these models have been used to gain insights into ocular hypertension (a major risk factor for glaucoma) and glaucomatous retinal ganglion cell death. Finally, the potential for developing new mouse models and using advanced genetic tools and resources for studying glaucoma are discussed. PMID:26116903

The gene therapy revolution in ophthalmology.

PubMed

Al-Saikhan, Fahad I

2013-04-01

The advances in gene therapy hold significant promise for the treatment of ophthalmic conditions. Several studies using animal models have been published. Animal models on retinitis pigmentosa, Leber's Congenital Amaurosis (LCA), and Stargardt disease have involved the use of adeno-associated virus (AAV) to deliver functional genes into mice and canines. Mice models have been used to show that a mutation in cGMP phosphodiesterase that results in retinitis pigmentosa can be corrected using rAAV vectors. Additionally, rAAV vectors have been successfully used to deliver ribozyme into mice with a subsequent improvement in autosomal dominant retinitis pigmentosa. By using dog models, researchers have made progress in studying X-linked retinitis pigmentosa which results from a RPGR gene mutation. Mouse and canine models have also been used in the study of LCA. The widely studied form of LCA is LCA2, resulting from a mutation in the gene RPE65. Mice and canines that were injected with normal copies of RPE65 gene showed signs such as improved retinal pigment epithelium transduction, visual acuity, and functional recovery. Studies on Stargardt disease have shown that mutations in the ABCA4 gene can be corrected with AAV vectors, or nanoparticles. Gene therapy for the treatment of red-green color blindness was successful in squirrel monkeys. Plans are at an advanced stage to begin clinical trials. Researchers have also proved that CD59 can be used with AMD. Gene therapy is also able to treat primary open angle glaucoma (POAG) in animal models, and studies show it is economically viable.

The gene therapy revolution in ophthalmology

PubMed Central

Al-Saikhan, Fahad I.

2013-01-01

The advances in gene therapy hold significant promise for the treatment of ophthalmic conditions. Several studies using animal models have been published. Animal models on retinitis pigmentosa, Leber’s Congenital Amaurosis (LCA), and Stargardt disease have involved the use of adeno-associated virus (AAV) to deliver functional genes into mice and canines. Mice models have been used to show that a mutation in cGMP phosphodiesterase that results in retinitis pigmentosa can be corrected using rAAV vectors. Additionally, rAAV vectors have been successfully used to deliver ribozyme into mice with a subsequent improvement in autosomal dominant retinitis pigmentosa. By using dog models, researchers have made progress in studying X-linked retinitis pigmentosa which results from a RPGR gene mutation. Mouse and canine models have also been used in the study of LCA. The widely studied form of LCA is LCA2, resulting from a mutation in the gene RPE65. Mice and canines that were injected with normal copies of RPE65 gene showed signs such as improved retinal pigment epithelium transduction, visual acuity, and functional recovery. Studies on Stargardt disease have shown that mutations in the ABCA4 gene can be corrected with AAV vectors, or nanoparticles. Gene therapy for the treatment of red–green color blindness was successful in squirrel monkeys. Plans are at an advanced stage to begin clinical trials. Researchers have also proved that CD59 can be used with AMD. Gene therapy is also able to treat primary open angle glaucoma (POAG) in animal models, and studies show it is economically viable. PMID:24227970

Assessment of narrow angles by gonioscopy, Van Herick method and anterior segment optical coherence tomography.

PubMed

Park, Seong Bae; Sung, Kyung Rim; Kang, Sung Yung; Jo, Jung Woo; Lee, Kyoung Sub; Kook, Michael S

2011-07-01

To evaluate anterior chamber (AC) angles using gonioscopy, Van Herick technique and anterior segment optical coherence tomography (AS-OCT). One hundred forty-eight consecutive subjects were enrolled. The agreement between any two of three diagnostic methods, gonioscopy, AS-OCT and Van Herick, was calculated in narrow-angle patients. The area under receiver-operating characteristic curves (AUC) for discriminating between narrow and open angles determined by gonioscopy was calculated in all participants for AS-OCT parameter angle opening distance (AOD), angle recess area, trabecular iris surface area and anterior chamber depth (ACD). As a subgroup analysis, capability of AS-OCT parameters for detecting angle closure defined by AS-OCT was assessed in narrow-angle patients. The agreement between the Van Herick method and gonioscopy in detecting angle closure was excellent in narrow angles (κ = 0.80, temporal; κ = 0.82, nasal). However, agreement between gonioscopy and AS-OCT and between the Van Herick method and AS-OCT was poor (κ = 0.11-0.16). Discrimination capability of AS-OCT parameters between open and narrow angles determined by gonioscopy was excellent for all AS-OCT parameters (AUC, temporal: AOD500 = 0.96, nasal: AOD500 = 0.99). The AUCs for detecting angle closure defined by AS-OCT image in narrow angle subjects was good for all AS-OCT parameters (AUC, 0.80-0.94) except for ACD (temporal: ACD = 0.70, nasal: ACD = 0.63). Assessment of narrow angles by gonioscopy and the Van Herick technique showed good agreement, but both measurements revealed poor agreement with AS-OCT. The angle closure detection capability of AS-OCT parameters was excellent; however, it was slightly lower in ACD.

System description and analysis. Part 1: Feasibility study for helicopter/VTOL wide-angle simulation image generation display system

NASA Technical Reports Server (NTRS)

1977-01-01

A preliminary design for a helicopter/VSTOL wide angle simulator image generation display system is studied. The visual system is to become part of a simulator capability to support Army aviation systems research and development within the near term. As required for the Army to simulate a wide range of aircraft characteristics, versatility and ease of changing cockpit configurations were primary considerations of the study. Due to the Army's interest in low altitude flight and descents into and landing in constrained areas, particular emphasis is given to wide field of view, resolution, brightness, contrast, and color. The visual display study includes a preliminary design, demonstrated feasibility of advanced concepts, and a plan for subsequent detail design and development. Analysis and tradeoff considerations for various visual system elements are outlined and discussed.

High Prevalence of Narrow Angles among Chinese-American Glaucoma and Glaucoma Suspect Patients

PubMed Central

Seider, Michael I; Pekmezci, Melike; Han, Ying; Sandhu, Simi; Kwok, Shiu Y; Lee, Roland Y; Lin, Shan C

2009-01-01

Purpose To evaluate the prevalence of gonioscopically narrow angles in a Chinese-American population with glaucoma or glaucoma suspicion. Patients and Methods Charts from all Chinese-American patients seen in a comprehensive ophthalmology clinic in the Chinatown district of San Francisco in 2002 were reviewed. One eye from each patient with glaucoma or glaucoma suspicion that met inclusion criteria was included (n=108). Data was collected for gender, age, race (self-declared), refraction (spherical equivalent), intraocular pressure (IOP), gonioscopy and vertical cup-to-disk ratio (CDR). Results Sixty percent (n=65) of Chinese-American eyes with glaucoma or glaucoma suspicion had gonioscopically narrow angles (Shaffer grade ≤2 in three or more quadrants). Those with narrow angles were significantly older (P=0.004) than their open angle counterparts, but the two groups did not differ in terms of gender, refraction, IOP or CDR (all, P≥0.071). In a multivariate model including age, gender and refraction as predictors of angle grade (open or narrow), only age was a significant predictor of angle grade (P=0.004). Conclusions A large proportion of Chinese-Americans in our study population with glaucoma or glaucoma suspicion had gonioscopically narrow angles. In multivariate analysis, patients with narrow angles were older than those with open angles but did not differ from them in terms of gender or refraction. Continued evaluation of angle closure glaucoma risk among Chinese-Americans is needed. PMID:19826385

Handbook of Supersonic Aerodynamics Volume 1

DTIC Science & Technology

1950-04-01

Appears in Z10 Publication Remarks •Mlc) *(lc) •Pile) Angle Potential function Helical angle of advance (propellers) Dimensionless Dependent on...heat of- combustion re(lc) N (cap) Nu. o(lc) Net Nozzle Normal (perpendicu- lar to longitudinal axis) ; normal (force) Nusselt ...Concepts ^ Concept Absolute Acceleration, angular Acceleration due to gravity Added; additional Adiabatic Adiabatic wall Advance, helical angle

[Emphasis on promotion of the adaptive technology is the sky point of improving of treatment and prevention level of glaucoma].

PubMed

Wang, Ning-li

2013-11-01

Promoting the control of primary angle-closure glaucoma (PACG) and primary open angle glaucoma (POAG) is most important prevention program of blindness in China. PACG has been incorporated into the prevention program of blindness in China based on the population-based screening studies. However, the clinical screening should be strengthened in POAG. The creation of a series of appropriate technologies suitable for glaucoma prevention and management has been achieved in China, especially for PACG. The technologies have been evaluated in the pilot areas and obtained very good results in China. It is recommended to develop new technology suitable for glaucoma management using the following workflow: research, development, and evaluation by large scale hospitals, and then clinical trial in the pilot areas. After a cost-benefit analysis is made, the new technology can be promoted and applied in clinical practice nationwide. We propose to gradually formed a strategical mode of "screening in township hospitals, intervention in county hospitals, and technical support and tackling in provincial hospitals" in order to improve the level of prevention and treatment of glaucoma and reduce the blindness incidence rate caused by glaucoma.

Comparison of a technique using a new percutaneous osteosynthesis device with conventional open surgery for displaced patella fractures in a randomized controlled trial.

PubMed

Luna-Pizarro, Daniel; Amato, Dante; Arellano, Francisco; Hernández, Armando; López-Rojas, Pablo

2006-09-01

To compare the percutaneous patellar osteosynthesis system (PPOS) technique with open surgery for patella fractures. Randomized controlled trial. Referral orthopedic and trauma center. Fifty-three patients with displaced patellar fractures. Stabilization and fixation of patellar fractures with PPOS or open surgery. Knee-flexion and -extension angles, pain, surgical time, and assessment of knee function based on the Knee Society Clinical Rating Scale (KSCRS). Comparison of PPOS and open-surgery groups at 4 weeks showed the following: pain, 3.7 +/- 1.6 versus 6.2 +/- 1.4 arbitrary units, P < 0.001; flexion angle, 46 +/- 20.7 versus 12.7 +/- 6.0 degrees, P < 0.001; extension angle, -2.5 versus -3.8 degrees, P < 0.001. At 8 weeks, the following was demonstrated: pain, 1.3 +/- 1.6 versus 4.1 +/- 2.1 arbitrary units, P < 0.001; flexion angle, 87 +/- 17.3 versus 34 +/- 26 degrees, P < 0.001; extension angle, 0 versus -3 degrees, P < 0.001. Surgical time was 35.3 +/- 7.8 versus 66.2 +/- 14.1 minutes, P < 0.001. KSCRS assessment was 84 +/- 4 versus 70 +/- 8, P < 0.001 at 8 weeks; 85 +/- 2 versus 73 +/- 8, P < 0.001 at 12 months; and 85 +/- 1 versus 82 +/- 7, P = 0.246 at 24 months. Frequency of total complications (infections, fragment displacement, and wire-related pain) was significantly lower in the PPOS than in the open-surgery group (P < 0.02). PPOS for patella fractures was associated with shorter surgical time, less pain, better mobility angles, higher functional score up to 2 years, and a lower incidence of complications than open surgery.

Regional distribution of circumferential residual strains in the human aorta according to age and gender.

PubMed

Sokolis, Dimitrios P; Savva, Giannis D; Papadodima, Stavroula A; Kourkoulis, Stavros K

2017-03-01

The biomechanical response of the human aorta varies with axial location, but little is known about the respective variation of residual strains. Such data are available for common lab animals, but in the traditional opening angle measurement the aorta is considered as an ideal cylinder and average residual strains are measured, so that the spatial variations of local residual strains are not determined. The present study provides opening angle and residual strain data throughout the course and around the circumference of the aorta harvested during autopsy. Opening angle showed notable topographical variation; the highest value was at the top of aortic arch, declining abruptly toward the ascending aorta and to a near-constant value in the descending aorta, and rising in the abdominal aorta. The variation of curvature and of external but not internal residual stretch resembled that of opening angle. Extensive residual stress and wall thickness differences were evidenced among quadrants, with the more pre-stressed being also the thicker quadrants. Gender had overall minor effects, but aging led to increased parameters, occurring earlier in the distal aorta but at later stages becoming predominant proximally. Differences in caliber were pronounced in older subjects, unlike those in opening angle, residual stretches, and thickness that were striking in middle-aged subjects. By contrast, curvature decreased with aging in relation to the smaller percentwise opening angle differences. Detailed knowledge of the zero-stress/no-load geometry of the human aortic wall is critical for an in-depth understanding of aortic physiology, while providing the basis for comparison with disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modification and performance evaluation of a mono-valve engine

NASA Astrophysics Data System (ADS)

Behrens, Justin W.

A four-stroke engine utilizing one tappet valve for both the intake and exhaust gas exchange processes has been built and evaluated. The engine operates under its own power, but has a reduced power capacity than the conventional 2-valve engine. The reduction in power is traced to higher than expected amounts of exhaust gases flowing back into the intake system. Design changes to the cylinder head will fix the back flow problems, but the future capacity of mono-valve engine technology cannot be estimated. The back flow of exhaust gases increases the exhaust gas recirculation (EGR) rate and deteriorates combustion. Intake pressure data shows the mono-valve engine requires an advanced intake valve closing (IVC) time to prevent back flow of charge air. A single actuation camshaft with advanced IVC was tested in the mono-valve engine, and was found to improve exhaust scavenging at TDC and nearly eliminated all charge air back flow at IVC. The optimum IVC timing is shown to be approximately 30 crank angle degrees after BDC. The mono-valve cylinder head utilizes a rotary valve positioned above the tappet valve. The open spaces inside the rotary valveand between the rotary valve and tappet valve represent a common volume that needs to be reduced in order to reduce the base EGR rate. Multiple rotary valve configurations were tested, and the size of the common volume was found to have no effect on back flow but a direct effect on the EGR rate and engine performance. The position of the rotary valve with respect to crank angle has a direct effect on the scavenging process. Optimum scavenging occurs when the intake port is opened just after TDC.

What Preoperative Radiographic Parameters Are Associated With Increased Medial Release in Total Knee Arthroplasty?

PubMed

Martin, J Ryan; Jennings, Jason M; Levy, Daniel L; Watters, Tyler Steven; Miner, Todd M; Dennis, Douglas A

2017-03-01

Preoperative varus deformity of the knee is a common malalignment in patients undergoing primary total knee arthroplasty (TKA). We are unaware of any studies that have correlated how various preoperative radiographic parameters can predict the amount of medial releases performed to achieve optimal coronal alignment and ligamentous balance. A retrospective review was performed on 67 patients who required at least a medial tibial reduction osteotomy (MTRO) during primary TKA to achieve coronal balance. This patient population was matched 1:1 to another cohort of TKA patients by age, gender, and body mass index who did not require an MTRO. A radiographic evaluation was used to compare the 2 cohorts. Preoperatively, the MTRO cohort was noted to have significantly increased varus tibiofemoral (86.12° vs 93.43°), tibial articular surface (85.79° vs 87.54°), and medial tibial articular surface angles (75.22° vs 85.34°) compared to the control cohort. The MTRO cohort had 3.13 mm of medial tibial offset and 9.06 mm of lateral joint space opening and the control cohort had 0.09 mm and 4.07 mm, respectively. The medial tibial articular surface angle and lateral joint space widening were statistically associated with the MTRO cohort. The final tibiofemoral angle in the MTRO cohort was 92.43° and was 93.40° in the control cohort. The MTRO cohort was noted to have several preoperative radiographic parameters that were significantly different than the control cohort. However, the medial tibial articular surface angle and lateral joint space widening were the only radiographic parameters that were statistically associated with requiring an MTRO. Copyright © 2016 Elsevier Inc. All rights reserved.

Some dissociating factors in the analysis of structural and functional progressive damage in open-angle glaucoma.

PubMed

Hudson, C J W; Kim, L S; Hancock, S A; Cunliffe, I A; Wild, J M

2007-05-01

To identify the presence, and origin, of any "dissociating factors" inherent to the techniques for evaluating progression that mask the relationship between structural and functional progression in open-angle glaucoma (OAG). 23 patients (14 with OAG and 9 with ocular hypertension (OHT)) who had received serial Heidelberg Retina Tomograph (HRT II) and Humphrey Field Analyser (HFA) examinations for >or=5 years (mean 78.4 months (SD 9.5), range 60-101 months) were identified. Evidence of progressive disease was retrospectively evaluated in one eye of each patient using the Topographic Change Analysis (TCA) and Glaucoma Progression Analysis (GPA) for the HRT II and HFA, respectively. Six patients were stable by both techniques; four exhibited both structural and functional progression; seven exhibited structural progression, only, and six showed functional progression, only. Three types of dissociating factors were identified. TCA failed to identify progressive structural damage in the presence of advanced optic nerve head damage. GPA failed to identify progressive functional damage at stimulus locations, with sensitivities exhibiting test-retest variability beyond the maximum stimulus luminance of the perimeter, and where a perimetric learning effect was apparent. The three dissociating factors accounted for nine of the 13 patients who exhibited a lack of concordance between structural and functional progressive damage.

Radiographic comparison of surgical hip dislocation and hip arthroscopy for treatment of cam deformity in femoroacetabular impingement.

PubMed

Bedi, Asheesh; Zaltz, Ira; De La Torre, Katrina; Kelly, Bryan T

2011-07-01

Whether open or arthroscopic techniques are employed, the goal of femoroacetabular impingement (FAI) surgery is to achieve impingement-free range of motion. While arthroscopic approaches have improved and gained popularity, an objective evaluation of the surgical correction achieved with this approach compared with open surgery remains to be defined in the literature. This study was undertaken to compare the efficacy of arthroscopic osteoplasty and open surgical dislocation in treating FAI dysmorphology in a consecutive series of patients. Cohort study; Level of evidence, 3. Surgical treatment was performed in 60 male patients under 40 years of age for symptomatic FAI refractory to nonoperative management. Patients were matched (not randomized) to treatment groups: 30 patients (15 left and 15 right hips) underwent arthroscopic cam and/or rim osteoplasty with labral debridement and/or refixation by an arthroscopic surgeon; and 30 (14 left and 16 right hips) underwent open surgical dislocation, cam and/or rim osteoplasty, and labral debridement or refixation by a hip preservation surgeon. Anteroposterior (AP) pelvis and extended-neck (Dunn) lateral radiographs were obtained and the depth of resection and arc of resection were measured by assessment of anterior femoral head-neck offset, AP and lateral α angle, and β angle on preoperative and postoperative radiographs. In the arthroscopic group, the extended-neck lateral α angle was reduced by a mean of 17.2° (28.3%, P < .05), AP α angle was reduced by a mean of 12.6° (16.8%), anterior head-neck offset improved 5.0 mm (111%, P < .05), and β angle increased by a mean of 23.1°. In the open dislocation group, the extended-neck lateral α angle was reduced by a mean of 21.2° (30.7%, P < .05), AP α angle was reduced by a mean of 20.1° (25.7%), anterior head-neck offset improved 6.56 mm (108%, P < .05), and β angle increased by a mean of 18.35°. Arthroscopic osteoplasty can restore head-neck offset and achieve similar depth, arc, and proximal-distal resection with comparable efficacy to open surgical dislocation for anterior and anterosuperior cam and focal rim impingement deformity. The open technique, however, may allow greater correction of posterosuperior loss of femoral offset and may be favorable for FAI patterns that demonstrate considerable proximal femoral deformity on AP radiographs.

Internal Performance of Several Divergent-Shroud Ejector Nozzles with High Divergence Angles

NASA Technical Reports Server (NTRS)

Trout, Arthur M.; Papell, S. Stephen; Povolny, John H.

1957-01-01

Nine divergent-shroud ejector configurations were investigated to determine the effect of shroud divergence angle on ejector internal performance. Unheated dry air was used for both the primary and secondary flows. The decrease in the design-point thrust coefficient with increasing flow divergence angle (angle measured from primary exit to shroud exit) followed very closely a simple relation involving the cosine of the angle. This indicates that design-point thrust performance for divergent-shroud ejectors can be predicted with reasonable accuracy within the range investigated. The decrease in design-point thrust coefficient due to increasing the flow divergence engle from 120deg to 30deg (half-singles) was approximately 6 percent. Ejector air-handling characteristics and the primary-nozzle flow coefficient were not significantly affected by change in shroud divergence angle.

Exfoliation syndrome and exfoliation glaucoma-associated LOXL1 variations are not involved in pigment dispersion syndrome and pigmentary glaucoma.

PubMed

Rao, Kollu Nageswara; Ritch, Robert; Dorairaj, Syril K; Kaur, Inderjeet; Liebmann, Jeffrey M; Thomas, Ravi; Chakrabarti, Subhabrata

2008-07-09

Single nucleotide polymorphisms (SNPs) in the LOXL1 gene have been implicated in exfoliation syndrome (XFS) and exfoliation glaucoma (XFG). We have shown that these SNPs are not associated with the primary glaucomas such as primary open-angle (POAG) glaucoma and primary angle-closure glaucoma (PACG). To further establish the specificity of LOXL1 SNPs for XFS and XFG, we determined whether these SNPs were involved in pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG). Three SNPs of LOXL1 (rs1048661, rs3825942, and rs2165241) were screened in a cohort of 78 unrelated and clinically well characterized glaucoma cases comprising of PG (n=44) and PDS (n=34) patients as well as 108 ethnically matched normal controls of Caucasian origin. The criteria for diagnosis of PDS/PG were Krukenberg spindle, hyperpigmentation of the trabecular meshwork, and wide open angle. Transillumination defects were detected by infrared pupillography, and the presence of a Zentmayer ring was considered as a confirmatory sign. All three SNPs were genotyped in cases and controls by resequencing the genomic region of LOXL1 harboring these variants and were further confirmed by polymerase chain reaction (PCR)-based restriction digestions. Haplotypes were generated from the genotype data, and the linkage disequilibrium (LD) and haplotype analysis were done with Haploview software that uses the expectation maximization (EM) algorithm. The LOXL1 SNPs showed no significant association with PDS or PG. There was no significant difference in the frequencies of the risk alleles of rs1048661 ('G' allele; p=0.309), rs3825942 ('G' allele' p=0.461), and rs2165241 ('T' allele; p=0.432) between PG/PDS cases and controls. Similarly, there was no involvement of the XFS/XFG-associated haplotypes, 'G-G' (p=0.643; [OR=1.08, 95%CI, 0.59-1.97]) and 'T-G' (p=0.266; [OR=1.35, 95%CI, 0.70-2.60]), with the PDS/PG phenotypes. The risk haplotype 'G-G' was observed in ~55% of the normal controls. There was no involvement of the LOXL1 SNPs in patients with PDS and PG. The results further indicate that the associations of these SNPs are specific to XFS/XFG.

Improving efficiency and access to mental health care: combining integrated care and advanced access.

PubMed

Pomerantz, Andrew; Cole, Brady H; Watts, Bradley V; Weeks, William B

2008-01-01

To provide an example of implementation of a new program that enhances access to mental health care in primary care. A general and specialized mental health service was redesigned to introduce open access to comprehensive mental health care in a primary care clinic. Key variables measured before and after implementation of the clinic included numbers of completed referrals, waiting time for appointments and clinic productivity. Workload and pre/post-implementation waiting time data were gathered through a computerized electronic monitoring system. Waiting time for new appointments was shortened from a mean of 33 days to 19 min. Clinician productivity and evaluations of new referrals more than doubled. These improvements have been sustained for 4 years. Moving mental health services into primary care, initiating open access and increasing use of technological aids led to dramatic improvements in access to mental health care and efficient use of resources. Implementation and sustainability of the program were enhanced by using a quality improvement approach.

MTHFR gene C677T and A1298C polymorphisms and homocysteine levels in primary open angle and primary closed angle glaucoma

PubMed Central

Micheal, Shazia; Qamar, Raheel; Akhtar, Farah; Khan, Muhammad Imran; Khan, Wajid Ali

2009-01-01

Purpose To investigate the methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C genotypes and plasma concentrations of total homocysteine (tHcy) in Pakistani patients with primary open angle glaucoma (POAG) and primary closed angle glaucoma (PCAG). Methods This was a prospective case-control study. A total of 295 patients (173 POAG, 122 PCAG) and 143 age- and sex-matched controls were subdivided into two ethnic groups, Punjabis (Punjab province, central Pakistan) and Pathans (North-West Frontier Province, northern Pakistan). Genotypes of the MTHFR C677T and A1298C polymorphisms were detected by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP). An enzyme-linked immunosorbent assay was used to determine the total serum homocysteine (tHcy) levels. Associations were determined by logistic regression analysis. Results Frequency distributions of genotypes and combined genotypes as well as homocysteine levels were obtained. The overall distribution of the C677T genotype was found to be significantly associated with PCAG (CC 69%, CT 21%, TT 10%; p=0.001, χ2=12.6), but not with POAG (CC 71%, CT 28%, TT 1%; p=0.98, χ2=0.02) as compared to the controls (CC 71%, CT 29%, TT 1%). The Pathan cohorts revealed no association with the disease; however, the Punjabis demonstrated a significant association with PCAG (CC 75%, CT 11%, TT 13%; p<0.001, χ2=17.2). PCAG in the Punjabi subjects was also significantly associated with the A1298C polymorphism (AA 43%, AC 54%, CC 3%; p<0.001, χ2=33.9) as compared to the controls. Combined genotype data showed no association with POAG; however, a significant association with all combined genotypes was observed in the overall PCAG subjects (p<0.05, χ2=20.1). This difference was particularly apparent in the TTAA and TTAC combinations that were completely absent in the control groups (p<0.05. χ2=49.6). Mean serum tHcy levels were found to be significantly increased in the POAG (15.2±1.28 µmol/l, p<0.001) and PCAG (20.8±4.8 µmol/l) groups as compared to the controls (10.0±0.97 µmol/l). The tHcy levels in the TT and AC genotype were significantly elevated in the PCAG group (67±12.39 µmol/l, p<0.001; 23±5.94 µmol/l, p=0.027) as compared to the controls. Conclusion The TT and AC genotypes of MTHFR C677T and A1298C polymorphisms and the combined genotype TTAC were associated with PCAG in Punjabi subjects of Pakistani origin and correlated with the high serum tHcy levels seen in these patients. PMID:19936026

Open-Label, Multicenter, Phase 1/2 Study of Tazemetostat (EZH2 Histone Methyl Transferase [HMT] Inhibitor) as a Single Agent in Subjects With Adv. Solid Tumors or With B-cell Lymphomas and Tazemetostat in Combination With Prednisolone in Subjects With DLBCL

ClinicalTrials.gov

2018-05-31

B-cell Lymphomas (Phase 1); Advanced Solid Tumors (Phase 1); Diffuse Large B-cell Lymphoma (Phase 2); Follicular Lymphoma (Phase 2); Transformed Follicular Lymphoma; Primary Mediastinal Large B-Cell Lymphoma

Characterization of the Intrinsic Water Wettability of Graphite Using Contact Angle Measurements: Effect of Defects on Static and Dynamic Contact Angles.

PubMed

Kozbial, Andrew; Trouba, Charlie; Liu, Haitao; Li, Lei

2017-01-31

Elucidating the intrinsic water wettability of the graphitic surface has increasingly attracted research interests, triggered by the recent finding that the well-established hydrophobicity of graphitic surfaces actually results from airborne hydrocarbon contamination. Currently, static water contact angle (WCA) is often used to characterize the intrinsic water wettability of graphitic surfaces. In the current paper, we show that because of the existence of defects, static WCA does not necessarily characterize the intrinsic water wettability. Freshly exfoliated graphite of varying qualities, characterized using atomic force microscopy and Raman spectroscopy, was studied using static, advancing, and receding WCA measurements. The results showed that graphite of different qualities (i.e., defect density) always has a similar advancing WCA, but it could have very different static and receding WCAs. This finding indicates that defects play an important role in contact angle measurements, and the static contact angle does not always represent the intrinsic water wettability of pristine graphite. On the basis of the experimental results, a qualitative model is proposed to explain the effect of defects on static, advancing, and receding contact angles. The model suggests that the advancing WCA reflects the intrinsic water wettability of pristine (defect-free) graphite. Our results showed that the advancing WCA for pristine graphite is 68.6°, which indicates that graphitic carbon is intrinsically mildly hydrophilic.

[Cardiac rehabilitation. Recent advances].

PubMed

Lellamo, Ferdinando; Volterrani, Maurizio

2010-03-01

Evidence derived from studies which support the relevance of exercise as a core component of cardiac rehabilitation programs are presented, along with the beneficial effects of exercise training in counteracting the mechanisms sustaining the atherosclerotic process and cardiovascular risk factors in the context of secundary, as well as primary, cardiovascular prevention. Practical guides to plan exercise training programs are also provided with suggestions for specific pathological conditions and advanced age. Recent advances on the benefits of exercise training in patients with heart failure are reported along with the potential of telemedicine for home rehabilitation aiming to a widespread diffusion of exercise as a cardiovascular therapy. Finally, the possible risks of exercise and practical open questions in cardiac rehabilitation are discussed.

Molecular genetics of the glaucomas: Mapping of the first five {open_quotes}GLC{close_quotes} loci

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raymond, V.

1997-02-01

Glaucoma encompasses a complex of ocular-disease entities characterized by an optic neuropathy in which degeneration of retinal ganglion cells leads to a characteristic excavation of the head of the optic nerve. Such damage causes progressive narrowing of the visual fields and, when uncontrolled, blindness. Affected people often have ocular hypertension defined as intraocular pressures consistently >21 mm Hg in both eyes. Although ocular hypertension is no longer an obligatory diagnostic criterion for glaucoma, it is still recognized as one of the most important risk factors. A diagnosis of glaucoma is made after observation of the characteristic atrophy of the opticmore » nerve, which is associated with typical visual field defects. In 1992, the World Health Organization estimated that, in the global population, 5.2 million people were blind as a result of glaucoma, making it the third leading cause of blindness worldwide. The most common form is adult-onset primary open-angle glaucoma, which represents {ge}50% of all cases of glaucoma. Among Caucasians, this form of the disorder affects {approximately}2% of the population >45 years old. In African Americans, prevalence of adult-onset open-angle glaucoma is three to four times higher than that observed in White Americans. More than 15 million North Americans may have some form of glaucoma, but at least half of them may not be aware of it. 43 refs., 1 tab.« less

LOXL1 deficiency in the lamina cribrosa as candidate susceptibility factor for a pseudoexfoliation-specific risk of glaucoma.

PubMed

Schlötzer-Schrehardt, Ursula; Hammer, Christian M; Krysta, Anita W; Hofmann-Rummelt, Carmen; Pasutto, Francesca; Sasaki, Takako; Kruse, Friedrich E; Zenkel, Matthias

2012-09-01

To test the hypothesis that a primary disturbance in lysyl oxidase-like 1 (LOXL1) and elastin metabolism in the lamina cribrosa of eyes with pseudoexfoliation syndrome constitutes an independent risk factor for glaucoma development and progression. Observational, consecutive case series. Posterior segment tissues obtained from 37 donors with early and late stages of pseudoexfoliation syndrome without glaucoma, 37 normal age-matched control subjects, 5 eyes with pseudoexfoliation-associated open-angle glaucoma, and 5 eyes with primary open-angle glaucoma (POAG). Protein and mRNA expression of major elastic fiber components (elastin, fibrillin-1, fibulin-4), collagens (types I, III, and IV), and lysyl oxidase crosslinking enzymes (LOX, LOXL1, LOXL2) were assessed in situ by quantitative real-time polymerase chain reaction, (immuno)histochemistry, and light and electron microscopy. Lysyl oxidase-dependent elastin fiber assembly was assessed by primary optic nerve head astrocytes in vitro. Expression levels of elastic proteins, collagens, and lysyl oxidases in the lamina cribrosa. Lysyl oxidase-like 1 proved to be the major lysyl oxidase isoform in the normal lamina cribrosa in association with a complex elastic fiber network. Compared with normal and POAG specimens, lamina cribrosa tissues obtained from early and late stages of pseudoexfoliation syndrome without and with glaucoma consistently revealed a significant coordinated downregulation of LOXL1 and elastic fiber constituents on mRNA and protein level. In contrast, expression levels of collagens and other lysyl oxidase isoforms were not affected. Dysregulated expression of LOXL1 and elastic proteins was associated with pronounced (ultra)structural alterations of the elastic fiber network in the laminar beams of pseudoexfoliation syndrome eyes. Inhibition of LOXL1 interfered with elastic fiber assembly by optic nerve head astrocytes in vitro. The findings provide evidence for a pseudoexfoliation-specific elastinopathy of the lamina cribrosa resulting from a primary disturbance in LOXL1 regulation and elastic fiber homeostasis, possibly rendering pseudoexfoliation syndrome eyes more vulnerable to pressure-induced optic nerve damage and glaucoma development and progression. Copyright © 2012 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500).

PubMed

Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun; Seong, Gong Je

2017-03-01

To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R²=0.404). Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors.

Correlations between Preoperative Angle Parameters and Postoperative Unpredicted Refractive Errors after Cataract Surgery in Open Angle Glaucoma (AOD 500)

PubMed Central

Lee, Wonseok; Bae, Hyoung Won; Lee, Si Hyung; Kim, Chan Yun

2017-01-01

Purpose To assess the accuracy of intraocular lens (IOL) power prediction for cataract surgery with open angle glaucoma (OAG) and to identify preoperative angle parameters correlated with postoperative unpredicted refractive errors. Materials and Methods This study comprised 45 eyes from 45 OAG subjects and 63 eyes from 63 non-glaucomatous cataract subjects (controls). We investigated differences in preoperative predicted refractive errors and postoperative refractive errors for each group. Preoperative predicted refractive errors were obtained by biometry (IOL-master) and compared to postoperative refractive errors measured by auto-refractometer 2 months postoperatively. Anterior angle parameters were determined using swept source optical coherence tomography. We investigated correlations between preoperative angle parameters [angle open distance (AOD); trabecular iris surface area (TISA); angle recess area (ARA); trabecular iris angle (TIA)] and postoperative unpredicted refractive errors. Results In patients with OAG, significant differences were noted between preoperative predicted and postoperative real refractive errors, with more myopia than predicted. No significant differences were recorded in controls. Angle parameters (AOD, ARA, TISA, and TIA) at the superior and inferior quadrant were significantly correlated with differences between predicted and postoperative refractive errors in OAG patients (-0.321 to -0.408, p<0.05). Superior quadrant AOD 500 was significantly correlated with postoperative refractive differences in multivariate linear regression analysis (β=-2.925, R2=0.404). Conclusion Clinically unpredicted refractive errors after cataract surgery were more common in OAG than in controls. Certain preoperative angle parameters, especially AOD 500 at the superior quadrant, were significantly correlated with these unpredicted errors. PMID:28120576

Surface step terrace tuned microstructures and dielectric properties of highly epitaxial CaCu3Ti4O12 thin films on vicinal LaAlO3 substrates

PubMed Central

Yao, Guang; Gao, Min; Ji, Yanda; Liang, Weizheng; Gao, Lei; Zheng, Shengliang; Wang, You; Pang, Bin; Chen, Y. B.; Zeng, Huizhong; Li, Handong; Wang, Zhiming; Liu, Jingsong; Chen, Chonglin; Lin, Yuan

2016-01-01

Controllable interfacial strain can manipulate the physical properties of epitaxial films and help understand the physical nature of the correlation between the properties and the atomic microstructures. By using a proper design of vicinal single-crystal substrate, the interface strain in epitaxial thin films can be well controlled by adjusting the miscut angle via a surface-step-terrace matching growth mode. Here, we demonstrate that LaAlO3 (LAO) substrates with various miscut angles of 1.0°, 2.75°, and 5.0° were used to tune the dielectric properties of epitaxial CaCu3Ti4O12 (CCTO) thin films. A model of coexistent compressive and tensile strained domains is proposed to understand the epitaxial nature. Our findings on the self-tuning of the compressive and tensile strained domain ratio along the interface depending on the miscut angle and the stress relaxation mechanism under this growth mode will open a new avenue to achieve CCTO films with high dielectric constant and low dielectric loss, which is critical for the design and integration of advanced heterostructures for high performance capacitance device applications. PMID:27703253

Surface step terrace tuned microstructures and dielectric properties of highly epitaxial CaCu3Ti4O12 thin films on vicinal LaAlO3 substrates

NASA Astrophysics Data System (ADS)

Yao, Guang; Gao, Min; Ji, Yanda; Liang, Weizheng; Gao, Lei; Zheng, Shengliang; Wang, You; Pang, Bin; Chen, Y. B.; Zeng, Huizhong; Li, Handong; Wang, Zhiming; Liu, Jingsong; Chen, Chonglin; Lin, Yuan

2016-10-01

Controllable interfacial strain can manipulate the physical properties of epitaxial films and help understand the physical nature of the correlation between the properties and the atomic microstructures. By using a proper design of vicinal single-crystal substrate, the interface strain in epitaxial thin films can be well controlled by adjusting the miscut angle via a surface-step-terrace matching growth mode. Here, we demonstrate that LaAlO3 (LAO) substrates with various miscut angles of 1.0°, 2.75°, and 5.0° were used to tune the dielectric properties of epitaxial CaCu3Ti4O12 (CCTO) thin films. A model of coexistent compressive and tensile strained domains is proposed to understand the epitaxial nature. Our findings on the self-tuning of the compressive and tensile strained domain ratio along the interface depending on the miscut angle and the stress relaxation mechanism under this growth mode will open a new avenue to achieve CCTO films with high dielectric constant and low dielectric loss, which is critical for the design and integration of advanced heterostructures for high performance capacitance device applications.

Surface step terrace tuned microstructures and dielectric properties of highly epitaxial CaCu3Ti4O12 thin films on vicinal LaAlO3 substrates.

PubMed

Yao, Guang; Gao, Min; Ji, Yanda; Liang, Weizheng; Gao, Lei; Zheng, Shengliang; Wang, You; Pang, Bin; Chen, Y B; Zeng, Huizhong; Li, Handong; Wang, Zhiming; Liu, Jingsong; Chen, Chonglin; Lin, Yuan

2016-10-05

Controllable interfacial strain can manipulate the physical properties of epitaxial films and help understand the physical nature of the correlation between the properties and the atomic microstructures. By using a proper design of vicinal single-crystal substrate, the interface strain in epitaxial thin films can be well controlled by adjusting the miscut angle via a surface-step-terrace matching growth mode. Here, we demonstrate that LaAlO 3 (LAO) substrates with various miscut angles of 1.0°, 2.75°, and 5.0° were used to tune the dielectric properties of epitaxial CaCu 3 Ti 4 O 12 (CCTO) thin films. A model of coexistent compressive and tensile strained domains is proposed to understand the epitaxial nature. Our findings on the self-tuning of the compressive and tensile strained domain ratio along the interface depending on the miscut angle and the stress relaxation mechanism under this growth mode will open a new avenue to achieve CCTO films with high dielectric constant and low dielectric loss, which is critical for the design and integration of advanced heterostructures for high performance capacitance device applications.

The Application of Visual Illusion in the Visual Communication Design

NASA Astrophysics Data System (ADS)

Xin, Tao; You Ye, Han

2018-03-01

With the development of our national reform, opening up and modernization, the science and technology has also been well developed and it has been applied in every wall of life, the development of visual illusion industry is represented in the widespread use of advanced technology in it. Ultimately, the visual illusion is a phenomenon, it should be analyzed from the angles of physics and philosophy. The widespread application of visual illusion not only can improve the picture quality, but also could maximize peoples’ sense degree through the visual communication design works, expand people’s horizons and promote the diversity of visual communication design works.

Multispectral Microimager for Astrobiology

NASA Technical Reports Server (NTRS)

Sellar, R. Glenn; Farmer, Jack D.; Kieta, Andrew; Huang, Julie

2006-01-01

A primary goal of the astrobiology program is the search for fossil records. The astrobiology exploration strategy calls for the location and return of samples indicative of environments conducive to life, and that best capture and preserve biomarkers. Successfully returning samples from environments conducive to life requires two primary capabilities: (1) in situ mapping of the mineralogy in order to determine whether the desired minerals are present; and (2) nondestructive screening of samples for additional in-situ testing and/or selection for return to laboratories for more in-depth examination. Two of the most powerful identification techniques are micro-imaging and visible/infrared spectroscopy. The design and test results are presented from a compact rugged instrument that combines micro-imaging and spectroscopic capability to provide in-situ analysis, mapping, and sample screening capabilities. Accurate reflectance spectra should be a measure of reflectance as a function of wavelength only. Other compact multispectral microimagers use separate LEDs (light-emitting diodes) for each wavelength and therefore vary the angles of illumination when changing wavelengths. When observing a specularly-reflecting sample, this produces grossly inaccurate spectra due to the variation in the angle of illumination. An advanced design and test results are presented for a multispectral microimager which demonstrates two key advances relative to previous LED-based microimagers: (i) acquisition of actual reflectance spectra in which the flux is a function of wavelength only, rather than a function of both wavelength and illumination geometry; and (ii) increase in the number of spectral bands to eight bands covering a spectral range of 468 to 975 nm.

OpenSeesPy: Python library for the OpenSees finite element framework

NASA Astrophysics Data System (ADS)

Zhu, Minjie; McKenna, Frank; Scott, Michael H.

2018-01-01

OpenSees, an open source finite element software framework, has been used broadly in the earthquake engineering community for simulating the seismic response of structural and geotechnical systems. The framework allows users to perform finite element analysis with a scripting language and for developers to create both serial and parallel finite element computer applications as interpreters. For the last 15 years, Tcl has been the primary scripting language to which the model building and analysis modules of OpenSees are linked. To provide users with different scripting language options, particularly Python, the OpenSees interpreter interface was refactored to provide multi-interpreter capabilities. This refactoring, resulting in the creation of OpenSeesPy as a Python module, is accomplished through an abstract interface for interpreter calls with concrete implementations for different scripting languages. Through this approach, users are able to develop applications that utilize the unique features of several scripting languages while taking advantage of advanced finite element analysis models and algorithms.

Flow field over the wing of a delta-wing fighter model with vortex control devices at Mach 0.6 to 1.2

NASA Technical Reports Server (NTRS)

Bare, E. Ann; Reubush, David E.; Haddad, Raymond C.

1992-01-01

As part of a cooperative research program between NASA, McDonnell Douglas Corporation, and Wright Research and Development Center, a flow field investigation was conducted on a 7.52 percent scale windtunnel model of an advanced fighter aircraft design. The investigation was conducted in the Langley 16 ft Transonic Tunnel at Mach numbers of 0.6, 0.9, and 1.2. Angle of attack was varied from -4 degrees to 30 degrees and the model was tested at angles of sideslip of 0, 5, and -5 degrees. Data for the over the wing flow field were obtained at four axial survey stations by the use of six 5 hole conical probes mounted on a survey mechanism. The wing leading edge primary vortex exerted the greatest influence in terms of total pressure loss on the over the wing flow field in the area surveyed. A number of vortex control devices were also investigated. They included two different apex flaps, wing leading edge vortex flaps, and small large wing fences. The vortex flap and both apex flaps were beneficial in controlling the wing leading edge primary vortex.

Assessment of Visual Status of the Aeta, a Hunter-Gatherer Population of the Philippines (An AOS Thesis)

PubMed Central

Allingham, R. Rand

2008-01-01

Purpose A screening study was performed to assess levels of visual impairment and blindness among a representative sample of older members of the Aeta, an indigenous hunter-gatherer population living on the island of Luzon in the Philippines. Methods Unrelated older Aeta couples were randomly invited to participate in a visual screening study. All consented individuals had ocular history, medical history, complete ophthalmic examination, height, weight, and blood pressure taken. Results A total of 225 individuals were screened from 4 villages. Visual acuity, both uncorrected and pinhole corrected, was significantly worse among older vs younger age-groups for women, men, and when combined (P < .001). Visual impairment was present in 48% of uncorrected and 43% of pinhole corrected eyes in the oldest age-group. Six percent of the screened population was bilaterally blind. The major causes of blindness were readily treatable. The most common etiologies as a proportion of blind eyes were cataract (66%), refractive error (20%), and trauma (7%). No cases of primary open-angle, primary angle-closure, or exfoliation glaucoma were observed in this population. Discussion Visual impairment and blindness were common in the Aeta population. Primary forms of glaucoma, a major cause of blindness found in most population-based studies, were not observed. The absence of primary glaucoma in this population may reflect random sampling error. However, based on similar findings in the Australian Aborigine, this raises the possibility that these two similar populations may share genetic and/or environmental factors that are protective for glaucoma.. PMID:19277240

Some Characteristics of Fuel Sprays from Open Nozzles

NASA Technical Reports Server (NTRS)

Rothrock, A M; Lee, D W

1930-01-01

The penetration and cone-angle of fuel sprays from open nozzles were recorded with the NACA Spray Photography Equipment. The results show that for injection systems in which the rate of pressure rise at the discharge orifice is high, open nozzles give spray-tip velocities and penetrations which compare favorably with those of closed nozzles. The spray cone-angle was the same for all tests, although open nozzles having different orifice diameters were used, and one nozzle was used both as an open and as a closed nozzle. In designing a fuel system using open nozzles, particular care must be taken to avoid air pockets. The check valve should be placed close to the discharge orifice.

What Are the Factors Influencing Implementation of Advanced Access in Family Medicine Units? A Cross-Case Comparison of Four Early Adopters in Quebec

PubMed Central

Touati, Nassera; Maillet, Lara; Gaboury, Isabelle

2017-01-01

Introduction Advanced access is an organizational model that has shown promise in improving timely access to primary care. In Quebec, it has recently been introduced in several family medicine units (FMUs) with a teaching mission. The objectives of this paper are to analyze the principles of advanced access implemented in FMUs and to identify which factors influenced their implementation. Methods A multiple case study of four purposefully selected FMUs was conducted. Data included document analysis and 40 semistructured interviews with health professionals and staff. Cross-case comparison and thematic analysis were performed. Results Three out of four FMUs implemented the key principles of advanced access at various levels. One scheduling pattern was observed: 90% of open appointment slots over three- to four-week periods and 10% of prebooked appointments. Structural and organizational factors facilitated the implementation: training of staff to support change, collective leadership, and openness to change. Conversely, family physicians practicing in multiple clinical settings, lack of team resources, turnover of clerical staff, rotation of medical residents, and management capacity were reported as major barriers to implementing the model. Conclusion Our results call for multilevel implementation strategies to improve the design of the advanced access model in academic teaching settings. PMID:28775899

Mickey Mouse Spotted on Mercury!

NASA Image and Video Library

2012-06-15

NASA image acquired: June 03, 2012 This scene is to the northwest of the recently named crater Magritte, in Mercury's south. The image is not map projected; the larger crater actually sits to the north of the two smaller ones. The shadowing helps define the striking "Mickey Mouse" resemblance, created by the accumulation of craters over Mercury's long geologic history. This image was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map is a major mapping activity in MESSENGER's extended mission and complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map is being acquired with an average resolution of 200 meters/pixel. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing. During the one-year primary mission, MESSENGER acquired 88,746 images and extensive other data sets. MESSENGER is now in a yearlong extended mission, during which plans call for the acquisition of more than 80,000 additional images to support MESSENGER's science goals. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Qualitative evaluation of the iris and ciliary body by ultrasound biomicroscopy in subjects with angle closure.

PubMed

Ku, Judy Y; Nongpiur, Monisha E; Park, Judy; Narayanaswamy, Arun K; Perera, Shamira A; Tun, Tin A; Kumar, Rajesh S; Baskaran, Mani; Aung, Tin

2014-12-01

To qualitatively analyze anterior chamber structures imaged by ultrasound biomicroscopy (UBM) in primary angle-closure patients. Subjects diagnosed as primary angle-closure suspect (PACS), primary angle-closure glaucoma (PACG), and previous acute primary angle closure (APAC) were recruited prospectively along with a group of normal controls. UBM was performed under standardized dark room conditions and qualitative assessment was carried out using a set of reference photographs of standard UBM images to categorize the various anatomic features related to angle configuration. These included overall and basal iris thicknesses, iris convexity, iris angulation, ciliary body size, and ciliary sulcus. A total of 60 PACS, 114 PACG, 41 APAC, and 33 normal controls were included. Patients were predominantly older Chinese females. After controlling the confounding effect of age and sex, eyes with overall thicker irides [medium odds ratio (OR) 3.58, thick OR 2.84] when compared with thin irides have a significantly higher likelihood of having PACS/PACG/APAC versus controls. Thicker basal iris component (medium OR 4.13, thick OR 3.39) also have higher likelihood of having angle closure when compared with thin basal iris thickness. Subjects with basal iris insertion, mild iris angulation, and large ciliary body have a higher OR of having angle closure. In contrast, the presence/absence of a ciliary sulcus did not influence the likelihood of angle closure. Eyes with thicker overall and basal iris thicknesses are more likely to have angle closure than controls. Other features that increase the likelihood of angle closure include basal iris insertion, mild iris angulation, and large ciliary body.

Reversible Self-Actuated Thermo-Responsive Pore Membrane

PubMed Central

Park, Younggeun; Gutierrez, Maria Paz; Lee, Luke P.

2016-01-01

Smart membranes, which can selectively control the transfer of light, air, humidity and temperature, are important to achieve indoor climate regulation. Even though reversible self-actuation of smart membranes is desirable in large-scale, reversible self-regulation remains challenging. Specifically, reversible 100% opening/closing of pore actuation showing accurate responsiveness, reproducibility and structural flexibility, including uniform structure assembly, is currently very difficult. Here, we report a reversible, thermo-responsive self-activated pore membrane that achieves opening and closing of pores. The reversible, self-actuated thermo-responsive pore membrane was fabricated with hybrid materials of poly (N-isopropylacrylamide), (PNIPAM) within polytetrafluoroethylene (PTFE) to form a multi-dimensional pore array. Using Multiphysics simulation of heat transfer and structural mechanics based on finite element analysis, we demonstrated that pore opening and closing dynamics can be self-activated at environmentally relevant temperatures. Temperature cycle characterizations of the pore structure revealed 100% opening ratio at T = 40 °C and 0% opening ratio at T = 20 °C. The flexibility of the membrane showed an accurate temperature-responsive function at a maximum bending angle of 45°. Addressing the importance of self-regulation, this reversible self-actuated thermo-responsive pore membrane will advance the development of future large-scale smart membranes needed for sustainable indoor climate control. PMID:27991563

Reversible Self-Actuated Thermo-Responsive Pore Membrane

NASA Astrophysics Data System (ADS)

Park, Younggeun; Gutierrez, Maria Paz; Lee, Luke P.

2016-12-01

Smart membranes, which can selectively control the transfer of light, air, humidity and temperature, are important to achieve indoor climate regulation. Even though reversible self-actuation of smart membranes is desirable in large-scale, reversible self-regulation remains challenging. Specifically, reversible 100% opening/closing of pore actuation showing accurate responsiveness, reproducibility and structural flexibility, including uniform structure assembly, is currently very difficult. Here, we report a reversible, thermo-responsive self-activated pore membrane that achieves opening and closing of pores. The reversible, self-actuated thermo-responsive pore membrane was fabricated with hybrid materials of poly (N-isopropylacrylamide), (PNIPAM) within polytetrafluoroethylene (PTFE) to form a multi-dimensional pore array. Using Multiphysics simulation of heat transfer and structural mechanics based on finite element analysis, we demonstrated that pore opening and closing dynamics can be self-activated at environmentally relevant temperatures. Temperature cycle characterizations of the pore structure revealed 100% opening ratio at T = 40 °C and 0% opening ratio at T = 20 °C. The flexibility of the membrane showed an accurate temperature-responsive function at a maximum bending angle of 45°. Addressing the importance of self-regulation, this reversible self-actuated thermo-responsive pore membrane will advance the development of future large-scale smart membranes needed for sustainable indoor climate control.

Columnar cell change with atypia (flat epithelial atypia) on breast core biopsy-outcomes following open excision.

PubMed

Biggar, Magdalena A; Kerr, Kris M; Erzetich, Lisa M; Bennett, Ian C

2012-01-01

Columnar cell change with atypia (CCCA) is a relatively recently recognized pathologic breast entity considered to be a risk factor for subsequent development of breast carcinoma. The aim of this study was to investigate the significance of finding CCCA on breast core biopsy, by establishing the frequency of other breast pathology on subsequently performed surgical excision specimens. All cases with CCCA as the most advanced lesion on core biopsy were reviewed. After excision, another advanced proliferative lesion was identified in 17 (33%) patients, including three patients (6%) with in situ or invasive carcinoma. An additional five patients (10%) were concurrently diagnosed with primary breast carcinoma at other sites. These findings indicate that when CCCA is found on core biopsy, open surgical biopsy of the relevant area should be performed and that workup of both breasts should be undertaken to exclude coexistent breast carcinoma at alternative sites. © 2012 Wiley Periodicals, Inc.

Occurrence of CYP1B1 Mutations in Juvenile Open-Angle Glaucoma With Advanced Visual Field Loss.

PubMed

Souzeau, Emmanuelle; Hayes, Melanie; Zhou, Tiger; Siggs, Owen M; Ridge, Bronwyn; Awadalla, Mona S; Smith, James E H; Ruddle, Jonathan B; Elder, James E; Mackey, David A; Hewitt, Alex W; Healey, Paul R; Goldberg, Ivan; Morgan, William H; Landers, John; Dubowsky, Andrew; Burdon, Kathryn P; Craig, Jamie E

2015-07-01

Juvenile open-angle glaucoma (JOAG) is a severe neurodegenerative eye disorder in which most of the genetic contribution remains unexplained. To assess the prevalence of pathogenic CYP1B1 sequence variants in an Australian cohort of patients with JOAG and severe visual field loss. For this cohort study, we recruited 160 patients with JOAG classified as advanced (n = 118) and nonadvanced (n = 42) through the Australian and New Zealand Registry of Advanced Glaucoma from January 1, 2007, through April 1, 2014. Eighty individuals with no evidence of glaucoma served as a control group. We defined JOAG as diagnosis before age 40 years and advanced JOAG as visual field loss in 2 of the 4 central fixation squares on a reliable visual field test result. We performed direct sequencing of the entire coding region of CYP1B1. Data analysis was performed in October 2014. Identification and characterization of CYP1B1 sequence variants. We identified 7 different pathogenic variants among 8 of 118 patients with advanced JOAG (6.8%) but none among the patients with nonadvanced JOAG. Three patients were homozygous or compound heterozygous for CYP1B1 pathogenic variants, which provided a likely basis for their disease. Five patients were heterozygous. The allele frequency among the patients with advanced JOAG (11 in 236 [4.7%]) was higher than among our controls (1 in 160 [0.6%]; P = .02; odds ratio, 7.8 [95% CI, 0.02-1.0]) or among the control population from the Exome Aggregation Consortium database (2946 of 122 960 [2.4%]; P = .02; odds ratio, 2.0 [95% CI, 0.3-0.9]). Individuals with CYP1B1 pathogenic variants, whether heterozygous or homozygous, had worse mean (SD) deviation on visual fields (-24.5 [5.1] [95% CI, -31.8 to -17.2] vs -15.6 [10.0] [95% CI, -17.1 to -13.6] dB; F1,126 = 5.90; P = .02; partial ηp2 = 0.05) and were younger at diagnosis (mean [SD] age, 23.1 [8.4] [95% CI, 17.2-29.1] vs 31.5 [8.0] [95% CI, 30.1-33.0] years; F1,122 = 7.18; P = .008; ηp2 = 0.06) than patients without CYP1B1 pathogenic variants. Patients with advanced JOAG based on visual field loss had enrichment of CYP1B1 pathogenic variants and a more severe phenotype compared with unaffected controls and patients with nonadvanced JOAG.

MOJAVE - XIV. Shapes and opening angles of AGN jets

NASA Astrophysics Data System (ADS)

Pushkarev, A. B.; Kovalev, Y. Y.; Lister, M. L.; Savolainen, T.

2017-07-01

We present 15 GHz stacked VLBA images of 373 jets associated with active galactic nuclei (AGNs) having at least five observing epochs within a 20 yr time interval 1994-2015 from the Monitoring Of Jets in Active galactic nuclei with VLBA Experiments (MOJAVE) programme and/or its precursor, the 2-cm VLBA Survey. These data are supplemented by 1.4 GHz single-epoch VLBA observations of 135 MOJAVE AGNs to probe larger scale jet structures. The typical jet geometry is found to be close to conical on scales from hundreds to thousands of parsecs, while a number of galaxies show quasi-parabolic streamlines on smaller scales. A true jet geometry in a considerable fraction of AGNs appears only after stacking epochs over several years. The jets with significant radial accelerated motion undergo more active collimation. We have analysed total intensity jet profiles transverse to the local jet ridgeline and derived both apparent and intrinsic opening angles of the flows, with medians of 21.5° and 1.3°, respectively. The Fermi LAT-detected gamma-ray AGNs in our sample have, on average, wider apparent and narrower intrinsic opening angle, and smaller viewing angle than non-LAT-detected AGNs. We have established a highly significant correlation between the apparent opening angle and gamma-ray luminosity, driven by Doppler beaming and projection effects.

Anterior capsule relaxing incisions with neodymium:YAG laser for patients at high-risk for anterior capsule contraction.

PubMed

Hayashi, Ken; Yoshida, Motoaki; Hirata, Akira; Hayashi, Hideyuki

2011-01-01

To examine the effect of anterior capsule relaxing incisions created with a neodymium:YAG (Nd:YAG) laser on prevention of anterior capsule contraction after cataract surgery in high-risk patients. Hayashi Eye Hospital, Fukuoka, Japan. Randomized masked clinical trials. Patients at high risk for anterior capsule contraction had anterior capsule relaxing incisions in either eye 3 days postoperatively. The anterior capsule opening was measured using a Scheimpflug videophotography system (EAS-1000) immediately and 1, 3, and 6 months after capsulotomy, and the percentage reduction in area was calculated. The degree of intraocular lens (IOL) decentration and tilt, posterior capsule opacification (PCO), and other complications were also assessed. Of the 84 patients included, 30 had primary angle closure, 28 had pseudoexfoliation, and 26 had diabetic retinopathy. There was no significant difference in the mean opening area between fellow eyes at baseline. In patients with primary angle closure, the area was significantly greater and the percentage reduction in area was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0428). In patients with pseudoexfoliation or diabetic retinopathy, the percentage reduction was significantly less in the capsulotomy group than in the no-capsulotomy group (P≤.0493), although there was no significant difference in area. No significant difference was found in IOL decentration or tilt, PCO, or incidence of other complications. Neodymium:YAG laser anterior capsule relaxing incisions in the early period after cataract surgery were effective in preventing anterior capsule contraction in high-risk patients and had no adverse effects. No author has a financial or proprietary interest in any material or method mentioned. Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

Diagnostic Consistency and Relation Between Optical Coherence Tomography and Standard Automated Perimetry in Primary Open-Angle Glaucoma.

PubMed

Toprak, Ibrahim; Yaylalı, Volkan; Yildirim, Cem

2017-01-01

To assess diagnostic consistency and relation between spectral-domain optical coherence tomography (SD-OCT) and standard automated perimetry (SAP) in patients with primary open-angle glaucoma (POAG). This retrospective study comprised 51 eyes of 51 patients with a confirmed diagnosis of POAG. The qualitative and quantitative SD-OCT parameters (retinal nerve fiber layer thicknesses [RNFL; average, superior, inferior, nasal and temporal], RNFL symmetry, rim area, disc area, average and vertical cup/disc [C/D] ratio and cup volume) were compared with parameters of SAP (mean deviation, pattern standard deviation, visual field index, and glaucoma hemifield test reports). Fifty-one eyes of 51 patients with POAG were recruited. Twenty-nine eyes (56.9%) had consistent RNFL and visual field (VF) damage. However, nine patients (17.6%) showed isolated RNFL damage on SD-OCT and 13 patients (25.5%) had abnormal VF test with normal RNFL. In patients with VF defect, age, average C/D ratio, vertical C/D ratio, and cup volume were significantly higher and rim area was lower when compared to those of the patients with normal VF. In addition to these parameters, worsening in average, superior, inferior, and temporal RNFL thicknesses and RNFL symmetry was significantly associated with consistent SD-OCT and SAP outcomes. In routine practice, patients with POAG can be manifested with inconsistent reports between SD-OCT and SAP. An older age, higher C/D ratio, larger cup volume, and lower rim area on SD-OCT appears to be associated with detectable VF damage. Moreover, additional worsening in RNFL parameters might reinforce diagnostic consistency between SD-OCT and SAP.

Axial Myopia Is Associated with Visual Field Prognosis of Primary Open-Angle Glaucoma

PubMed Central

Qiu, Chen; Qian, Shaohong; Sun, Xinghuai; Zhou, Chuandi; Meng, Fanrong

2015-01-01

Purpose To identify whether myopia was associated with the visual field (VF) progression of primary open-angle glaucoma (POAG). Methods A total of 270 eyes of 270 POAG followed up for more than 3 years with ≥9 reliable VFs by Octopus perimetry were retrospectively reviewed. Myopia was divided into: mild myopia (-2.99 diopter [D], 0), moderate myopia (-5.99, 3.00 D), marked myopia (-9.00, -6.00 D) and non-myopia (0 D or more). An annual change in the mean defect (MD) slope >0.22 dB/y and 0.30 dB/y was defined as fast progression, respectively. Logistic regression was performed to determine prognostic factors for VF progression. Results For the cutoff threshold at 0.22 dB/y, logistic regression showed that vertical cup-to-disk ratio (VCDR; p = 0.004) and the extent of myopia (p = 0.002) were statistically significant. When logistic regression was repeated after excluding the extent of myopia, axial length (AL; p = 0.008, odds ratio [OR] = 0.796) reached significance, as did VCDR (p = 0.001). Compared to eyes with AL≤23 mm, the OR values were 0.334 (p = 0.059), 0.309 (p = 0.044), 0.266 (p = 0.019), 0.260 (p = 0.018), respectively, for 23 26 mm. The significance of vertical cup-to-disk ratio of (p = 0.004) and the extent of myopia (p = 0.008) did not change for the cutoff threshold at 0.30dB/y. Conclusions VCDR and myopia were associated with VF prognosis of POAG. Axial myopia may be a protective factor against VF progression. PMID:26214313

Association of fatty acid-binding protein 2 and fat mass and obesity-associated gene polymorphism with primary open-angle glaucoma

PubMed Central

Abbas, Shania; Raza, Syed Tasleem; Chandra, Anu; Singh, Luxmi; Mahdi, Farzana

2017-01-01

PURPOSE: The present study was carried out to investigate the association of fatty acid-binding protein 2 (FABP2) and fat mass and obesity-associated (FTO) gene polymorphism with primary open-angle glaucoma (POAG) cases and controls. MATERIALS AND METHODS: This study includes 122 POAG cases and 112 controls. FABP2 and FTO gene polymorphisms in cases and controls were evaluated by polymerase chain reaction-restriction fragment length polymorphism method. RESULTS: The mean ages were 49.88 ± 12.34 and 53.74 ± 11.87 years in POAG cases and control groups, respectively. The FABP2 gene AA, AT, TT genotype frequencies were 12.90%, 62.40%, 24.80% in POAG cases and 20.60%, 64.70%, 14.70% in healthy controls, respectively. The frequencies of A and T allele in POAG cases were 44.06% and 55.94% as compared to 52.94% and 47.06% in the controls. The FTO gene AA, AT, TT genotype frequencies were 2.00%, 79.20%, 18.80% in cases and 0%, 75.50%, 24.50% in healthy controls, respectively. The frequencies of A and T allele in POAG cases were 41.58% and 58.42% as compared to 37.75% and 62.25% in the controls. No significant difference in the frequencies of FABP2 and FTO genotype was found between POAG cases and controls. CONCLUSION: We could not identify the possible association of FABP2 and FTO gene polymorphism with POAG; however, further studies with larger sample size in different population are require to clarify the role of FABP2 and FTO genes in susceptibility to POAG. PMID:29034152

A Pilot Study to Evaluate the Oral Microbiome and Dental Health in Primary Open-Angle Glaucoma.

PubMed

Polla, Daniel; Astafurov, Konstantin; Hawy, Eman; Hyman, Leslie; Hou, Wei; Danias, John

2017-04-01

To evaluate possible associations between primary open-angle glaucoma (POAG), dental health, and the oral microbiome. Case-control study was conducted at SUNY Downstate. Adult subjects (40 to 87 y) were recruited as POAG cases (n=119) and controls without glaucoma (n=78) based on visual field and optic nerve criteria. Overall 74.6% were African Americans (AA). Information on medical history and oral health was collected and ophthalmologic examinations were performed. Mouthwash specimens (28 AA cases and 17 controls) were analyzed for bacterial DNA amounts. Analyses were limited to AAs as the predominant racial group. Outcome measures included number of natural teeth, self-reported periodontal health parameters, and amounts and prevalence of oral bacterial species. Logistic regression was used to evaluate associated factors and potential interactions. Cases and controls had similar age (mean: 62.2 and 60.9 y, respectively, P>0.48), and frequency of hypertension, diabetes, but cases had a higher proportion of men (P<0.04). On average (±SD), cases had fewer natural teeth than controls [18.0 (±11.1) vs. 20.7 (±9.4)]. Having more natural teeth was inversely associated with POAG, in multivariable analyses, at older ages [eg, odds ratio (95% confidence interval) at age 55: 1.0 (0.95-1.06), P=0.98 vs. at age 85: 0.87 (0.79-0.96), P=0.007]. Amounts of Streptococci were higher in cases than controls (P<0.03) in samples from the subset of subjects analyzed. The number of teeth (an oral health indicator) and alterations in the amounts of oral bacteria may be associated with glaucoma pathology. Further investigation of the association between dental health and glaucoma is warranted.

Vascular tone pathway polymorphisms in relation to primary open-angle glaucoma.

PubMed

Kang, J H; Loomis, S J; Yaspan, B L; Bailey, J C; Weinreb, R N; Lee, R K; Lichter, P R; Budenz, D L; Liu, Y; Realini, T; Gaasterland, D; Gaasterland, T; Friedman, D S; McCarty, C A; Moroi, S E; Olson, L; Schuman, J S; Singh, K; Vollrath, D; Wollstein, G; Zack, D J; Brilliant, M; Sit, A J; Christen, W G; Fingert, J; Forman, J P; Buys, E S; Kraft, P; Zhang, K; Allingham, R R; Pericak-Vance, M A; Richards, J E; Hauser, M A; Haines, J L; Wiggs, J L; Pasquale, L R

2014-06-01

Vascular perfusion may be impaired in primary open-angle glaucoma (POAG); thus, we evaluated a panel of markers in vascular tone-regulating genes in relation to POAG. We used Illumina 660W-Quad array genotype data and pooled P-values from 3108 POAG cases and 3430 controls from the combined National Eye Institute Glaucoma Human Genetics Collaboration consortium and Glaucoma Genes and Environment studies. Using information from previous literature and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, we compiled single-nucleotide polymorphisms (SNPs) in 186 vascular tone-regulating genes. We used the 'Pathway Analysis by Randomization Incorporating Structure' analysis software, which performed 1000 permutations to compare the overall pathway and selected genes with comparable randomly generated pathways and genes in their association with POAG. The vascular tone pathway was not associated with POAG overall or POAG subtypes, defined by the type of visual field loss (early paracentral loss (n=224 cases) or only peripheral loss (n=993 cases)) (permuted P≥0.20). In gene-based analyses, eight were associated with POAG overall at permuted P<0.001: PRKAA1, CAV1, ITPR3, EDNRB, GNB2, DNM2, HFE, and MYL9. Notably, six of these eight (the first six listed) code for factors involved in the endothelial nitric oxide synthase activity, and three of these six (CAV1, ITPR3, and EDNRB) were also associated with early paracentral loss at P<0.001, whereas none of the six genes reached P<0.001 for peripheral loss only. Although the assembled vascular tone SNP set was not associated with POAG, genes that code for local factors involved in setting vascular tone were associated with POAG.

Oral Administration of Forskolin, Homotaurine, Carnosine, and Folic Acid in Patients with Primary Open Angle Glaucoma: Changes in Intraocular Pressure, Pattern Electroretinogram Amplitude, and Foveal Sensitivity.

PubMed

Mutolo, Maria Giulia; Albanese, Giuseppe; Rusciano, Dario; Pescosolido, Nicola

2016-04-01

To evaluate the effects of a food supplement containing forskolin, homotaurine, carnosine, folic acid, vitamins B1, B2, B6, and magnesium in patients with primary open angle glaucoma (POAG) already in treatment and compensated by intraocular pressure (IOP)-lowering drugs, during a period of 12 months. Twenty-two patients (44 eyes) with POAG, with their IOP compensated by topical drugs, were enrolled and randomly assigned to the food supplement or control treatment group. The additional food supplement treatment consisted of 2 tablets per day (1 in the morning, 1 in the evening) given for 1 year of a balanced association of homotaurine, Coleus forskohlii root extract, L-carnosine, folic acid, vitamins B1, B2, B6, and magnesium. Pattern Electroretinogram (PERG) amplitude, foveal sensitivity obtained with the visual field analyzer frequency doubling technology, and IOP were detected at enrollment (T0), 3 months (T1), 6 months (T2), 9 months (T3), and 12 months (T4). We observed in treated patients a significant further decrease of IOP and an improvement of PERG amplitude at 6, 9, and 12 months, and foveal sensitivity at 12 months. All values remained substantially stable in control patients. The results of the present pilot study indicate that the components of the food supplement reach the eye in a detectable manner, as evidenced by the effects on the IOP. Moreover, they suggest a short-term neuroactive effect, as indicated by the improvement of PERG amplitude and foveal sensitivity in treated, but not in control patients.

Estrogen pathway polymorphisms in relation to primary open angle glaucoma: An analysis accounting for gender from the United States

PubMed Central

Loomis, Stephanie J.; Weinreb, Robert N.; Kang, Jae H.; Yaspan, Brian L.; Bailey, Jessica Cooke; Gaasterland, Douglas; Gaasterland, Terry; Lee, Richard K.; Scott, William K.; Lichter, Paul R.; Budenz, Donald L.; Liu, Yutao; Realini, Tony; Friedman, David S.; McCarty, Catherine A.; Moroi, Sayoko E.; Olson, Lana; Schuman, Joel S.; Singh, Kuldev; Vollrath, Douglas; Wollstein, Gadi; Zack, Donald J.; Brilliant, Murray; Sit, Arthur J.; Christen, William G.; Fingert, John; Kraft, Peter; Zhang, Kang; Allingham, R. Rand; Pericak-Vance, Margaret A.; Richards, Julia E.; Hauser, Michael A.; Haines, Jonathan L.; Wiggs, Janey L.

2013-01-01

Purpose Circulating estrogen levels are relevant in glaucoma phenotypic traits. We assessed the association between an estrogen metabolism single nucleotide polymorphism (SNP) panel in relation to primary open angle glaucoma (POAG), accounting for gender. Methods We included 3,108 POAG cases and 3,430 controls of both genders from the Glaucoma Genes and Environment (GLAUGEN) study and the National Eye Institute Glaucoma Human Genetics Collaboration (NEIGHBOR) consortium genotyped on the Illumina 660W-Quad platform. We assessed the relation between the SNP panels representative of estrogen metabolism and POAG using pathway- and gene-based approaches with the Pathway Analysis by Randomization Incorporating Structure (PARIS) software. PARIS executes a permutation algorithm to assess statistical significance relative to the pathways and genes of comparable genetic architecture. These analyses were performed using the meta-analyzed results from the GLAUGEN and NEIGHBOR data sets. We evaluated POAG overall as well as two subtypes of POAG defined as intraocular pressure (IOP) ≥22 mmHg (high-pressure glaucoma [HPG]) or IOP <22 mmHg (normal pressure glaucoma [NPG]) at diagnosis. We conducted these analyses for each gender separately and then jointly in men and women. Results Among women, the estrogen SNP pathway was associated with POAG overall (permuted p=0.006) and HPG (permuted p<0.001) but not NPG (permuted p=0.09). Interestingly, there was no relation between the estrogen SNP pathway and POAG when men were considered alone (permuted p>0.99). Among women, gene-based analyses revealed that the catechol-O-methyltransferase gene showed strong associations with HTG (permuted gene p≤0.001) and NPG (permuted gene p=0.01). Conclusions The estrogen SNP pathway was associated with POAG among women. PMID:23869166

Association of Interleukin-1 gene clusters polymorphisms with primary open-angle glaucoma: a meta-analysis.

PubMed

Li, Junhua; Feng, Yifan; Sung, Mi Sun; Lee, Tae Hee; Park, Sang Woo

2017-11-28

Previous studies have associated the Interleukin-1 (IL-1) gene clusters polymorphisms with the risk of primary open-angle glaucoma (POAG). However, the results were not consistent. Here, we performed a meta-analysis to evaluate the role of IL-1 gene clusters polymorphisms in POAG susceptibility. PubMed, EMBASE and Cochrane Library (up to July 15, 2017) were searched by two independent investigators. All case-control studies investigating the association between single-nucleotide polymorphisms (SNPs) of IL-1 gene clusters and POAG risk were included. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated for quantifying the strength of association that has been involved in at least two studies. Five studies on IL-1β rs16944 (c. -511C > T) (1053 cases and 986 controls), 4 studies on IL-1α rs1800587 (c. -889C > T) (822 cases and 714 controls), and 4 studies on IL-1β rs1143634 (c. +3953C > T) (798 cases and 730 controls) were included. The results suggest that all three SNPs were not associated with POAG risk. Stratification analyses indicated that the rs1143634 has a suggestive associated with high tension glaucoma (HTG) under dominant (P = 0.03), heterozygote (P = 0.04) and allelic models (P = 0.02), however, the weak association was nullified after Bonferroni adjustments for multiple tests. Based on current meta-analysis, we indicated that there is lack of association between the three SNPs of IL-1 and POAG. However, this conclusion should be interpreted with caution and further well designed studies with large sample-size are required to validate the conclusion as low statistical powers.

Serotonin levels in aqueous humor of patients with primary open-angle glaucoma.

PubMed

Zanon-Moreno, V; Melo, P; Mendes-Pinto, M M; Alves, C J; Garcia-Medina, J J; Vinuesa-Silva, I; Moreno-Nadal, M A; Pinazo-Duran, M D

2008-01-01

Glaucoma is an optic neuropathy characterized by a high intraocular pressure (IOP), alterations in optic nerve head, and loss of visual field that could lead to bilateral blindness. Serotonin (5-HT) is a biogenic monoamine that is synthesized from hydroxylation of tryptophan and acts by three ways, dissemination, metabolism, and reuptake in synaptic cleft through specific systems of the membrane. The purpose of this study is to evaluate the 5-HT and 5-HIAA (5-hydroxiindolacetic acid) levels in the aqueous humor of patients with primary open-angle glaucoma (POAG). We performed a case-control study, and the patients recruited were classified into two groups, 1) 30 patients with POAG (GG) and 2) 30 patients with cataracts (CG), who acted as the controls. Aqueous humor samples of each patient were obtained by paracentesis at the beginning of the surgical procedures. 5-HT and 5-HIAA levels were determined by high performance liquid chromatography (HPLC) with electrochemical detection. There were no statistical differences between age (71.3 +/- 7.2 years in GG, 73.5 +/- 9.0 years in CG; p=0.2581) or gender (sex ratio 0.765 in GG and 0.667 in CG). 5-HT levels were lower in GG, but this difference was not significant (p=0.820). We observed a statistically significant higher level of 5-HIAA in GG (p=0.001). The 5-HT turnover (5-HIAA/5-HT) were higher in GG than in CG (p<0.05), but the difference was not significant (p=0.598). The level of 5-HT was lower in GG patients, and the level of 5-HIAA was higher in GG patients than in CG patients.

Sodium 4-phenylbutyrate acts as a chemical chaperone on misfolded myocilin to rescue cells from endoplasmic reticulum stress and apoptosis.

PubMed

Yam, Gary Hin-Fai; Gaplovska-Kysela, Katarina; Zuber, Christian; Roth, Jürgen

2007-04-01

To evaluate the effect of chemical chaperones on the trafficking of secretion-incompetent primary open-angle glaucoma-associated mutant myocilin and the possibility to rescue cells coexpressing mutant and wild-type myocilin from endoplasmic reticulum (ER) stress and apoptosis. CHO-K1, HEK293 and human trabecular meshwork cells were transfected to express wild-type or mutant (C245Y, G364V, P370L, Y437H) myocilin-green fluorescent protein fusion protein and were treated or not with various chemical chaperones (glycerol, dimethylsulfoxide, or sodium 4-phenylbutyrate) for different time periods. The secretion, Triton X-100 solubility, and intracellular distribution of wild-type and mutant myocilin were analyzed by immunoprecipitation, Western blotting, and confocal double immunofluorescence. The effect of sodium 4-phenylbutyrate on ER stress proteins and apoptosis was examined in cells coexpressing mutant and wild-type myocilin. Treatment with sodium 4-phenylbutyrate, but not with glycerol or dimethylsulfoxide, reduced the amount of detergent-insoluble myocilin aggregates, diminished myocilin interaction with calreticulin, and restored the secretion of mutant myocilin. Heteromeric complexes formed by mutant and wild-type myocilin induced the ER stress-associated phosphorylated form of ER-localized eukaryotic initiation factor (eIF)-2alpha kinase and the active form of caspase 3, which resulted in an increased rate of apoptosis. Sodium 4-phenylbutyrate treatment of cells coexpressing mutant and wild-type myocilin relieved ER stress and significantly reduced the rate of apoptosis. These findings indicate that sodium 4-phenylbutyrate protects cells from the deleterious effects of ER-retained aggregated mutant myocilin. These data point to the possibility of a chemical chaperone treatment for myocilin-caused primary open-angle glaucoma.

Risk factors for predicting visual field progression in Chinese patients with primary open-angle glaucoma: A retrospective study.

PubMed

Hung, Kuo-Hsuan; Cheng, Ching-Yu; Liu, Catherine Jui-Ling

2015-07-01

Glaucoma is a leading cause of irreversible blindness worldwide. It is characterized by progressive deterioration of the visual field (VF) that results in a complete loss of vision. This study aimed to determine the risk factors associated with VF progression in Chinese patients with primary open-angle glaucoma (POAG). We reviewed the charts of POAG patients who visited our clinic between July 2009 and June 2010. We included patients with five or more reliable VF tests using the Humphrey Field Analyzer (Humphrey Instruments, San Leandro, CA, USA) during a period of at least 2 years. The scoring system of the Collaborative Initial Glaucoma Treatment Study (CIGTS) was used to code the VF. Progression was defined as an increasing score ≥3, compared to the averaged baseline data. Univariate and multivariate logistic regression analyses were performed to identify the risk factors of VF progression. There were 92 patients (representing 92 eyes) with an average of 8.9 reliable VFs over a mean follow up of 5.4 years. Multivariate logistic regression showed that eyes with more VF tests [odds ratio (OR) = 1.500, p < 0.010] and either increased peak intraocular pressure (IOP) (OR = 1.235, p = 0.044) or a wide IOP range (OR = 1.165, p = 0.041) favored VF progression. High myopia (less than -6.0 D) was not a risk factor (OR = 1.289, p = 0.698) for VF progression in this study. In addition to a greater number of VF tests, Chinese patients with treated POAG who experienced a high peak IOP or a wide range of IOP during follow up were more likely to have VF deterioration. Copyright © 2015. Published by Elsevier Taiwan.

The Optic Nerve Head in Primary Open-Angle Glaucoma Eyes With High Myopia: Characteristics and Association With Visual Field Defects.

PubMed

Chen, Li-Wei; Lan, Yu-Wen; Hsieh, Jui-Wen

2016-06-01

To evaluate the morphologic characteristics of optic neuropathy and its association with visual field (VF) defects in primary open-angle glaucoma (POAG) eyes with high myopia. In this cross-sectional study, we reviewed data from 375 Taiwanese patients (375 eyes) of POAG, ages 20 to 60 years. Optic disc photographs were used for planimetric measurements of morphologic variables. The myopic refraction was divided into high myopia (<-6.0 D) and nonhigh myopia (moderate myopia to hyperopia). The optic disc area was classified as moderate (1.59 to 2.85 mm), large, and small. Differences in characteristics between groups, correlations with the disc area, and factors associated with VF defects were determined. Of the 142 highly myopic eyes, 33 (23%) had a large disc, 26 (18%) had a small disc, and 55 (39%) had a tilted disc. Large discs had a higher cup-to-disc (C/D) area ratio and a higher tilt ratio; small discs had a smaller rim area and a lower tilt ratio (all P<0.05). Characteristics associated with high myopia included a smaller rim area, a higher C/D area ratio, and a lower tilt ratio (all P<0.001). In logistic regression, the refraction, the C/D area ratio, the rim area, and the tilt ratio (all P<0.05) were associated with VF defects. In Taiwanese individuals with POAG, our study found that tilted, large, or small discs were prevalent in highly myopic eyes. Of these characteristics, only the disc tilt and high myopia by itself were associated with the severity of glaucomatous optic neuropathy.

Genetic correlations between intraocular pressure, blood pressure and primary open-angle glaucoma: a multi-cohort analysis.

PubMed

Aschard, Hugues; Kang, Jae H; Iglesias, Adriana I; Hysi, Pirro; Cooke Bailey, Jessica N; Khawaja, Anthony P; Allingham, R Rand; Ashley-Koch, Allison; Lee, Richard K; Moroi, Sayoko E; Brilliant, Murray H; Wollstein, Gadi; Schuman, Joel S; Fingert, John H; Budenz, Donald L; Realini, Tony; Gaasterland, Terry; Scott, William K; Singh, Kuldev; Sit, Arthur J; Igo, Robert P; Song, Yeunjoo E; Hark, Lisa; Ritch, Robert; Rhee, Douglas J; Gulati, Vikas; Haven, Shane; Vollrath, Douglas; Zack, Donald J; Medeiros, Felipe; Weinreb, Robert N; Cheng, Ching-Yu; Chasman, Daniel I; Christen, William G; Pericak-Vance, Margaret A; Liu, Yutao; Kraft, Peter; Richards, Julia E; Rosner, Bernard A; Hauser, Michael A; Klaver, Caroline C W; vanDuijn, Cornelia M; Haines, Jonathan; Wiggs, Janey L; Pasquale, Louis R

2017-11-01

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.

Proteomic Alterations in Aqueous Humor From Patients With Primary Open Angle Glaucoma.

PubMed

Sharma, Shruti; Bollinger, Kathryn E; Kodeboyina, Sai Karthik; Zhi, Wenbo; Patton, Jordan; Bai, Shan; Edwards, Blake; Ulrich, Lane; Bogorad, David; Sharma, Ashok

2018-05-01

Primary open angle glaucoma (POAG) is the most prevalent form of glaucoma, accounting for approximately 90% of all cases. The aqueous humor (AH), a biological fluid in the anterior and posterior chambers of the eye, is involved in a multitude of functions including the maintenance of IOP and ocular homeostasis. This fluid is very close to the pathologic site and is also known to have a significant role in glaucoma pathogenesis. The purpose of this study was to identify proteomic alterations in AH from patients with POAG. AH samples were extracted from 47 patients undergoing cataract surgery (controls: n = 32; POAG: n = 15). Proteomic analysis of the digested samples was accomplished by liquid-chromatography-mass spectrometry. The identified proteins were evaluated using a variety of statistical and bioinformatics methods. A total of 33 proteins were significantly altered in POAG subjects compared with the controls. The most abundant proteins in POAG subjects are IGKC (13.56-fold), ITIH4 (4.1-fold), APOC3 (3.36-fold), IDH3A (3.11-fold), LOC105369216 (2.98-fold). SERPINF2 (2.94-fold), NPC2 (2.88-fold), SUCLG2 (2.70-fold), KIAA0100 (2.29-fold), CNOT4 (2.23-fold), AQP4 (2.11-fold), COL18A1 (2.08-fold), NWD1 (2.07-fold), and TMEM120B (2.06-fold). A significant increasing trend in the odds ratios of having POAG was observed with increased levels of these proteins. Proteins identified in this study are implicated in signaling, glycosylation, immune response, molecular transport, and lipid metabolism. The identified candidate proteins may be potential biomarkers associated with POAG development and may lead to more insight in understanding the mechanisms underlying the pathogenesis of this disease.

Involvement of genetic variants associated with primary open-angle glaucoma in pathogenic mechanisms and family history of glaucoma.

PubMed

Mabuchi, Fumihiko; Sakurada, Yoichi; Kashiwagi, Kenji; Yamagata, Zentaro; Iijima, Hiroyuki; Tsukahara, Shigeo

2015-03-01

To investigate the associations between the non-intraocular pressure (IOP)-related genetic variants (genetic variants associated with vulnerability of the optic nerve independent of IOP) and primary open-angle glaucoma (POAG), including normal-tension glaucoma (NTG) and high-tension glaucoma (HTG), and between the non-IOP-related genetic variants and a family history of glaucoma. Case-control study. Japanese patients with NTG (n = 213) and HTG (n = 212) and 191 control subjects were genotyped for 5 non-IOP-related genetic variants predisposing to POAG near the SRBD1, ELOVL5, CDKN2B/CDKN2B-AS1, SIX1/SIX6, and ATOH7 genes. The load of these genetic variants was compared between the control subjects and patients with NTG or HTG and between the POAG patients with and without a family history of glaucoma. The total number of POAG risk alleles and the product of the odds ratios (POAG risk) of these genetic variants were significantly larger (P < .0025) in patients with both NTG and HTG than in the control subjects, and were significantly larger (P = .0042 and P = .023, respectively) in POAG patients with a family history of glaucoma than in those without. As the number of relatives with glaucoma increased, the total number of risk alleles and the product of the odds ratios increased (P = .012 and P = .047, respectively). Non-IOP-related genetic variants contribute to the pathogenesis of HTG as well as NTG. A positive family history of glaucoma in cases of POAG is thought to reflect the influence of genetic variants predisposing to POAG. Copyright © 2015 Elsevier Inc. All rights reserved.

Comparison of diagnostic capability of macular ganglion cell complex and retinal nerve fiber layer among primary open angle glaucoma, ocular hypertension, and normal population using Fourier-domain optical coherence tomography and determining their functional correlation in Indian population

PubMed Central

Barua, Nabanita; Sitaraman, Chitra; Goel, Sonu; Chakraborti, Chandana; Mukherjee, Sonai; Parashar, Hemandra

2016-01-01

Context: Analysis of diagnostic ability of macular ganglionic cell complex and retinal nerve fiber layer (RNFL) in glaucoma. Aim: To correlate functional and structural parameters and comparing predictive value of each of the structural parameters using Fourier-domain (FD) optical coherence tomography (OCT) among primary open angle glaucoma (POAG) and ocular hypertension (OHT) versus normal population. Setting and Design: Single centric, cross-sectional study done in 234 eyes. Materials and Methods: Patients were enrolled in three groups: POAG, ocular hypertensive and normal (40 patients in each group). After comprehensive ophthalmological examination, patients underwent standard automated perimetry and FD-OCT scan in optic nerve head and ganglion cell mode. The relationship was assessed by correlating ganglion cell complex (GCC) parameters with mean deviation. Results were compared with RNFL parameters. Statistical Analysis: Data were analyzed with SPSS, analysis of variance, t-test, Pearson's coefficient, and receiver operating curve. Results: All parameters showed strong correlation with visual field (P < 0.001). Inferior GCC had highest area under curve (AUC) for detecting glaucoma (0.827) in POAG from normal population. However, the difference was not statistically significant (P > 0.5) when compared with other parameters. None of the parameters showed significant diagnostic capability to detect OHT from normal population. In diagnosing early glaucoma from OHT and normal population, only inferior GCC had statistically significant AUC value (0.715). Conclusion: In this study, GCC and RNFL parameters showed equal predictive capability in perimetric versus normal group. In early stage, inferior GCC was the best parameter. In OHT population, single day cross-sectional imaging was not valuable. PMID:27221682

Visual disability in newly diagnosed primary open angle glaucoma (POAG) patients in a tertiary hospital in Nigeria.

PubMed

Awoyesuku, E A; Ejimadu, C S

2012-01-01

Glaucoma remains the second leading cause of blindness worldwide and the highes cause of irreversible blindness worldwide. In N Glaucoma accounts for 16% of blindness and primary open angle glaucoma is the most prevalent clinical type. The aim of this study is to assess the visual disability resulting from glaucoma in newly diagnosed POAG patients in University of Port Harcourt Teaching Hospital. This is a retrospective study of newly diagnosed glaucoma patients referred from the general ophthalmology clinic to the glaucoma clinic over a 12 month period (January-December 2010). All patients had a glaucoma workup includin Snellen distant visual acuity, slit lamp examination, Goldman applanation tonometry, gonioscopy, dilated fundoscopy with +78 diopter lens as well as perimetry. All examinations were carried out by both authors. Patients with other co-morbidities such as cataract and retinal/macular pathologies were excluded from the study. A total of 98 patients were reviewed. The were 34 males and 27 females, giving a male to female ratio of 1.3:1. The average age was 54.2 years and most patients (>80%) were in the 40-59 year age group. Of the 98 patients reviewed, 62.2% had POAG. 30 patients were-blind by distant visual acuity criteria while 45 patients were blind by central visual field criteria. POAG is the most prevalent clinical subtype of glaucoma in Nigeria and sub-Saharan Africa Paucity of symptoms in early stages of the disease at late presentation is a characteristic finding in our clinic environment. Our study showed that POAG in our environment is associated with marked visual disability at the time of presentation.

Genome-wide analysis of central corneal thickness in primary open-angle glaucoma cases in the NEIGHBOR and GLAUGEN consortia.

PubMed

Ulmer, Megan; Li, Jun; Yaspan, Brian L; Ozel, Ayse Bilge; Richards, Julia E; Moroi, Sayoko E; Hawthorne, Felicia; Budenz, Donald L; Friedman, David S; Gaasterland, Douglas; Haines, Jonathan; Kang, Jae H; Lee, Richard; Lichter, Paul; Liu, Yutao; Pasquale, Louis R; Pericak-Vance, Margaret; Realini, Anthony; Schuman, Joel S; Singh, Kuldev; Vollrath, Douglas; Weinreb, Robert; Wollstein, Gadi; Zack, Donald J; Zhang, Kang; Young, Terri; Allingham, R Rand; Wiggs, Janey L; Ashley-Koch, Allison; Hauser, Michael A

2012-07-03

To investigate the effects of central corneal thickness (CCT)-associated variants on primary open-angle glaucoma (POAG) risk using single nucleotide polymorphisms (SNP) data from the Glaucoma Genes and Environment (GLAUGEN) and National Eye Institute (NEI) Glaucoma Human Genetics Collaboration (NEIGHBOR) consortia. A replication analysis of previously reported CCT SNPs was performed in a CCT dataset (n = 1117) and these SNPs were then tested for association with POAG using a larger POAG dataset (n = 6470). Then a CCT genome-wide association study (GWAS) was performed. Top SNPs from this analysis were selected and tested for association with POAG. cDNA libraries from fetal and adult brain and ocular tissue samples were generated and used for candidate gene expression analysis. Association with one of 20 previously published CCT SNPs was replicated: rs12447690, near the ZNF469 gene (P = 0.001; β = -5.08 μm/allele). None of these SNPs were significantly associated with POAG. In the CCT GWAS, no SNPs reached genome-wide significance. After testing 50 candidate SNPs for association with POAG, one SNP was identified, rs7481514 within the neurotrimin (NTM) gene, that was significantly associated with POAG in a low-tension subset (P = 0.00099; Odds Ratio [OR] = 1.28). Additionally, SNPs in the CNTNAP4 gene showed suggestive association with POAG (top SNP = rs1428758; P = 0.018; OR = 0.84). NTM and CNTNAP4 were shown to be expressed in ocular tissues. The results suggest previously reported CCT loci are not significantly associated with POAG susceptibility. By performing a quantitative analysis of CCT and a subsequent analysis of POAG, SNPs in two cell adhesion molecules, NTM and CNTNAP4, were identified and may increase POAG susceptibility in a subset of cases.

Comparison of Pattern Electroretinography and Optical Coherence Tomography Parameters in Patients with Primary Open-Angle Glaucoma and Ocular Hypertension

PubMed Central

Tiryaki Demir, Semra; Oba, Mehmet Ersin; Erdoğan, Ezgi Tuna; Odabaşı, Mahmut; Dirim, Ayşe Burcu; Demir, Mehmet; Can, Efe; Kara, Orhan; Yekta Şendül, Selam

2015-01-01

Objectives: To investigate the correlation of visual field (VF), pattern electroretinography (PERG) and Fourier domain optical coherence tomography (FD-OCT) results in patients with ocular hypertension (OHT) and early primary open-angle glaucoma (POAG). Materials and Methods: The study included 72 eyes of 37 patients with early POAG, 76 eyes of 38 patients with OHT, and 60 eyes of 30 controls. All subjects underwent full ophthalmologic examination, VF assessment with 24-2 Humphrey standard automated perimetry (Swedish Interactive Thresholding Algorithm (SITA)-Standard), retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) thickness measurement with FD-OCT, and PERG P50 and N95 wave latency and amplitude measurements with electroretinography (Nihon Kohden). Results: With the exception of the nasal quadrant, all GCC parameters and RNFL results were significantly lower in the POAG group compared to the OHT and control groups. There was no statistically significant difference between the OHT and control group. PERG amplitudes were lower in the POAG and OHT groups than in the control group. Reduction in N95 amplitude was greater than that of P50 amplitude. No difference was detected in PERG latencies among groups. GCC was significantly correlated with VF and RNFL in the POAG group. Conclusion: Significant thinning of the GCC and RNFL occurs in addition to VF pathologies in patients with early POAG, and these examinations should be concomitantly evaluated. During diagnostic assessment of patients with early POAG, GCC and RNFL analysis by FD-OCT are highly effective. GCC is as reliable as RNLF in the early diagnosis of glaucoma and there is a highly significant correlation between them. Dysfunction of ganglion cells in patients with OHT may be detected earlier using PERG amplitude analysis. PMID:27800239

Evaluating intraocular pressure-lowering solutions for the treatment of open-angle glaucoma: comparison between bimatoprost 0.03% and bimatoprost 0.01% - an observational switch study.

PubMed

Deshpande, Sarita S; Sonty, Sriram; Ahmad, Afzal

2017-01-01

The purpose of this study is to evaluate the intraocular pressure (IOP)-lowering efficacy of bimatoprost 0.01% solution in patients with primary open-angle glaucoma (POAG), who were switched from bimatoprost 0.03% solution, compared to patients with POAG who continued on bimatoprost 0.03% solution. A retrospective review evaluated 35 patients (35 right eyes [OD], 34 left eyes [OS]) who remained on bimatoprost 0.03% and 30 patients (27 OD, 30 OS) who were switched to bimatoprost 0.01% during the period January 8, 2010 to December 26, 2012. Mean IOP was measured 6 and 3 months before the switch, at switch, and 3, 6, and 12 months after the switch. Hyperemia scores were recorded before and after the switch and were compared to a picture scale. Mean IOP in the group that switched was 16.96±5.03 mmHg in OD and 17.67±5.33 mmHg in OS at baseline. Mean IOP postswitch to bimatoprost 0.01% solution was 17.60±4.34 mmHg in OD and 17.00±3.37 mmHg in OS. IOP was not significantly reduced in either OD or OS postswitch to bimatoprost 0.01% ( P 1 =0.5 OD, P 2 =0.2 OS). The hyperemia scores improved remarkably when bimatoprost 0.03% solution was switched to bimatoprost 0.01% solution ( P <0.001). To our knowledge, this is the first switch study evaluating the hypotensive efficacy and tolerability of bimatoprost in a group of patients with open-angle glaucoma. In this study comparing bimatoprost 0.03% and 0.01% solution, we found improved tolerability postswitch to 0.01% from 0.03% bimatoprost, similar efficacy between the two concentrations before and after switch in the same patient population, and similar IOPs comparable to nonswitch bimatoprost 0.03% solution.

A multicenter, retrospective chart review study comparing index therapy change rates in open-angle glaucoma or ocular hypertension patients newly treated with latanoprost or travoprost-Z monotherapy.

PubMed

Fain, Joel M; Kotak, Sameer; Mardekian, Jack; Bacharach, Jason; Edward, Deepak P; Rauchman, Steven; Brevetti, Teresa; Fox, Janet L; Lovelace, Cherie

2011-06-13

Because latanoprost and the original formulation of travoprost that included benzalkonium chloride (BAK) have been shown to be similar with regard to tolerability, we compared initial topical intraocular pressure (IOP)-lowering medication change rates in patients newly treated with latanoprost or travoprost-Z monotherapy. At 14 clinical practice sites, medical records were abstracted for patients with a diagnosis of open-angle glaucoma or ocular hypertension and who were ≥40 years of age, had a baseline and at least one follow-up visit, and had no prior history of ocular prostaglandin use. Data regarding demographics, ocular/systemic medical histories, clinical variables, therapy initiations and reasons for changes, adverse events, and resource utilization were recorded from randomly chosen eligible charts. Primary outcomes were rates of and reasons for changing from the initial therapy within six months and across the full study period (1000 days). Data from 900 medical charts (latanoprost, 632; travoprost-Z, 268) were included. For both cohorts, average follow-up was >1 year. Cohorts were similar with regard to age (median ~67 years), gender distribution (>50% female), and diagnosis (~80% with open-angle glaucoma). Within six months, rates of index therapy change for latanoprost versus travoprost-Z were 21.2% (134/632) and 28.7% (77/268), respectively (p = 0.0148); across the full study period, rates were 34.5% (218/632) and 45.2% (121/268), respectively (p = 0.0026). Among those who changed their index therapy, insufficient IOP control was the most commonly reported reason followed by adverse events; hyperemia was the most commonly reported adverse event at index therapy change. In this "real world" study of changes in therapy in patients prescribed initial monotherapy with latanoprost with BAK or travoprost-Z with SofZia, medication changes were common in both treatment groups but statistically significantly more frequent with travoprost-Z.

Comparison of a travoprost BAK-free formulation preserved with polyquaternium-1 with BAK-preserved travoprost in ocular hypertension or open-angle glaucoma.

PubMed

Gandolfi, Stefano; Paredes, Tania; Goldberg, Ivan; Coote, Michael; Wells, Anthony; Volksone, Lasma; Pillai, Manju R; Stalmans, Ingeborg; Denis, Philippe

2012-01-01

To demonstrate that the intraocular pressure (IOP)-lowering effect of travoprost 0.004% preserved with polyquaternium-1 (travoprost benzalkonium chloride [BAK]-free) is non-inferior to that of travoprost 0.004% preserved with benzalkonium chloride (travoprost BAK) in patients with ocular hypertension or open-angle glaucoma. A total of 371 patients randomly received travoprost BAK-free (n=185) or travoprost BAK (n=186) dosed once daily in the evening for 3 months. Patients were evaluated at 9 am, 11 AM, and 4 PM at baseline, weeks 2 and 6, and month 3. Intraocular pressure was also evaluated 36 and 60 hours after the month 3 visit. Travoprost BAK-free is non-inferior to travoprost BAK. The 95% upper confidence limits for the difference in mean IOP at month 3 (primary efficacy) were 0.5 mmHg, 0.6 mmHg, and 0.5 mmHg, at 9 AM, 11 AM, and 4 PM, respectively. Mean IOP reductions from baseline ranged from 7.6 to 8.7 mmHg in the travoprost BAK-free group and from 7.7 to 9.2 mmHg in the travoprost BAK group. At 36 and 60 hours after the last dose, mean IOP remained 6.8 mmHg and 5.7 mmHg below baseline in the travoprost BAK-free group, vs 7.3 mmHg and 6.0 mmHg in the travoprost BAK group, respectively. The safety profile of travoprost BAK-free was similar to that of travoprost BAK. Travoprost BAK-free safely and effectively lowers IOP in eyes with open-angle glaucoma or ocular hypertension. This BAK-free formulation has comparable safety, efficacy, and duration of IOP-lowering effect to travoprost preserved with BAK. Travoprost BAK-free is an effective option for IOP reduction while avoiding BAK exposure.

Racial Disparities in the Quality of Prostate Cancer Care

DTIC Science & Technology

2015-11-01

Treatment Primary treatment was categorized into surgery (open, laparoscopic or robotic -assisted radical prostatectomy), radiotherapy (External Beam...Introduction: For younger men (ឱ years of age) with high risk locally advanced (>stage 2C), active treatment with surgery or radiotherapy appears to...to disease state, or from peer experiences. Feeling like treatments were all about equal, so prefer surgery to have clear pathology report. 7

Gravity field error analysis for pendulum formations by a semi-analytical approach

NASA Astrophysics Data System (ADS)

Li, Huishu; Reubelt, Tilo; Antoni, Markus; Sneeuw, Nico

2017-03-01

Many geoscience disciplines push for ever higher requirements on accuracy, homogeneity and time- and space-resolution of the Earth's gravity field. Apart from better instruments or new observables, alternative satellite formations could improve the signal and error structure compared to Grace. One possibility to increase the sensitivity and isotropy by adding cross-track information is a pair of satellites flying in a pendulum formation. This formation contains two satellites which have different ascending nodes and arguments of latitude, but have the same orbital height and inclination. In this study, the semi-analytical approach for efficient pre-mission error assessment is presented, and the transfer coefficients of range, range-rate and range-acceleration gravitational perturbations are derived analytically for the pendulum formation considering a set of opening angles. The new challenge is the time variations of the opening angle and the range, leading to temporally variable transfer coefficients. This is solved by Fourier expansion of the sine/cosine of the opening angle and the central angle. The transfer coefficients are further applied to assess the error patterns which are caused by different orbital parameters. The simulation results indicate that a significant improvement in accuracy and isotropy is obtained for small and medium initial opening angles of single polar pendulums, compared to Grace. The optimal initial opening angles are 45° and 15° for accuracy and isotropy, respectively. For a Bender configuration, which is constituted by a polar Grace and an inclined pendulum in this paper, the behaviour of results is dependent on the inclination (prograde vs. retrograde) and on the relative baseline orientation (left or right leading). The simulation for a sun-synchronous orbit shows better results for the left leading case.

Flow field and performance characteristics of combustor diffusers: A basic study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hestermann, R.; Kim, S.; Ben Khaled, A.

1995-10-01

Results of a detailed study concerning the influence of geometric as well as fluid mechanic parameters o the performance of a plane model combustor diffuser in cold flow are presented. For a qualitative insight into the complex flow field inside the prediffuser, the sudden expansion region, and the flow field around the flame tube dome, results of a flow visualization study with the hydrogen bubble method as well as with the ink jet method are presented for different opening angles of the prediffuser and for different flame tube distances. Also, quantitative data from detailed measurements with LDV and conventional pressuremore » probes in a geometrically similar air-driven setup are presented. These data clearly demonstrate the effect of boundary layer thickness as well as the influence of different turbulence levels at the entry of the prediffuser on the performance characteristics of combustor diffusers. The possibility of getting an unseparated flow field inside the prediffuser even at large opening angles by appropriately matching the diffuser`s opening angle and the flame tube distance is demonstrated. Also, for flows with an increased turbulence level at the entrance--all other conditions held constant--an increased opening angle can be realized without experiencing flow separation. The comparison of the experimental data with predictions utilizing a finite-volume-code based on a body-fitted coordinate system for diffusers with an included total opening angle less than 18 deg demonstrates the capability of describing the flow field in combustor diffusers with reasonable accuracy.« less

Maximizing cost-effectiveness by adjusting treatment strategy according to glaucoma severity

PubMed Central

Guedes, Ricardo Augusto Paletta; Guedes, Vanessa Maria Paletta; Gomes, Carlos Eduardo de Mello; Chaoubah, Alfredo

2016-01-01

Abstract Background: The aim of this study is to determine the most cost-effective strategy for the treatment of primary open-angle glaucoma (POAG) in Brazil, from the payer's perspective (Brazilian Public Health System) in the setting of the Glaucoma Referral Centers. Methods: Study design was a cost-effectiveness analysis of different treatment strategies for POAG. We developed 3 Markov models (one for each glaucoma stage: early, moderate and advanced), using a hypothetical cohort of POAG patients, from the perspective of the Brazilian Public Health System (SUS) and a horizon of the average life expectancy of the Brazilian population. Different strategies were tested according to disease severity. For early glaucoma, we compared observation, laser and medications. For moderate glaucoma, medications, laser and surgery. For advanced glaucoma, medications and surgery. Main outcome measures were ICER (incremental cost-effectiveness ratio), medical direct costs and QALY (quality-adjusted life year). Results: In early glaucoma, both laser and medical treatment were cost-effective (ICERs of initial laser and initial medical treatment over observation only, were R$ 2,811.39/QALY and R$ 3,450.47/QALY). Compared to observation strategy, the two alternatives have provided significant gains in quality of life. In moderate glaucoma population, medical treatment presented the highest costs among treatment strategies. Both laser and surgery were highly cost-effective in this group. For advanced glaucoma, both tested strategies were cost-effective. Starting age had a great impact on results in all studied groups. Initiating glaucoma therapy using laser or surgery were more cost-effective, the younger the patient. Conclusion: All tested treatment strategies for glaucoma provided real gains in quality of life and were cost-effective. However, according to the disease severity, not all strategies provided the same cost-effectiveness profile. Based on our findings, there should be a preferred strategy for each glaucoma stage, according to a cost-effectiveness ratio ranking. PMID:28033286

Statistical contact angle analyses; "slow moving" drops on a horizontal silicon-oxide surface.

PubMed

Schmitt, M; Grub, J; Heib, F

2015-06-01

Sessile drop experiments on horizontal surfaces are commonly used to characterise surface properties in science and in industry. The advancing angle and the receding angle are measurable on every solid. Specially on horizontal surfaces even the notions themselves are critically questioned by some authors. Building a standard, reproducible and valid method of measuring and defining specific (advancing/receding) contact angles is an important challenge of surface science. Recently we have developed two/three approaches, by sigmoid fitting, by independent and by dependent statistical analyses, which are practicable for the determination of specific angles/slopes if inclining the sample surface. These approaches lead to contact angle data which are independent on "user-skills" and subjectivity of the operator which is also of urgent need to evaluate dynamic measurements of contact angles. We will show in this contribution that the slightly modified procedures are also applicable to find specific angles for experiments on horizontal surfaces. As an example droplets on a flat freshly cleaned silicon-oxide surface (wafer) are dynamically measured by sessile drop technique while the volume of the liquid is increased/decreased. The triple points, the time, the contact angles during the advancing and the receding of the drop obtained by high-precision drop shape analysis are statistically analysed. As stated in the previous contribution the procedure is called "slow movement" analysis due to the small covered distance and the dominance of data points with low velocity. Even smallest variations in velocity such as the minimal advancing motion during the withdrawing of the liquid are identifiable which confirms the flatness and the chemical homogeneity of the sample surface and the high sensitivity of the presented approaches. Copyright © 2014 Elsevier Inc. All rights reserved.

Hong's grading for evaluating anterior chamber angle width.

PubMed

Kim, Seok Hwan; Kang, Ja Heon; Park, Ki Ho; Hong, Chul

2012-11-01

To compare Hong's grading method with anterior segment optical coherence tomography (AS-OCT), gonioscopy, and the dark-room prone-position test (DRPT) for evaluating anterior chamber width. The anterior chamber angle was graded using Hong's grading method, and Hong's angle width was calculated from the arctangent of Hong's grades. The correlation between Hong's angle width and AS-OCT parameters was analyzed. The area under the receiver operating characteristic curve (AUC) for Hong's grading method when discriminating between narrow and open angles as determined by gonioscopy was calculated. Correlation analysis was performed between Hong's angle width and intraocular pressure (IOP) changes determined by DRPT. A total of 60 subjects were enrolled. Of these subjects, 53.5 % had a narrow angle. Hong's angle width correlated significantly with the AS-OCT parameters (r = 0.562-0.719, P < 0.01). A Bland-Altman plot showed relatively good agreement between Hong's angle width and the angle width obtained by AS-OCT. The ability of Hong's grading method to discriminate between open and narrow angles was good (AUC = 0.868, 95 % CI 0.756-0.942). A significant linear correlation was found between Hong's angle width and IOP change determined by DRPT (r = -0.761, P < 0.01). Hong's grading method is useful for detecting narrow angles. Hong's grading correlated well with AS-OCT parameters and DRPT.

Mechanical strength assessment of a drilled hole in the contralateral cortex at the end of the open wedge for high tibial osteotomy.

PubMed

Diffo Kaze, Arnaud; Maas, Stefan; Hoffmann, Alexander; Pape, Dietrich

2017-12-01

This study aimed to investigate, by means of finite element analysis, the effect of a drill hole at the end of a horizontal osteotomy to reduce the risk of lateral cortex fracture while performing an opening wedge high tibial osteotomy (OWHTO). The question was whether drilling a hole relieves stress and increases the maximum correction angle without fracture of the lateral cortex depending on the ductility of the cortical bone. Two different types of osteotomy cuts were considered; one with a drill hole (diameter 5 mm) and the other without the hole. The drill holes were located about 20 mm distally to the tibial plateau and 6 mm medially to the lateral cortex, such that the minimal thickness of the contralateral cortical bone was 5 mm. Based on finite element calculations, two approaches were used to compare the two types of osteotomy cuts considered: (1) Assessing the static strength using local stresses following the idea of the FKM-guideline, subsequently referred to as the "FKM approach" and (2) limiting the total strain during the opening of the osteotomy wedge, subsequently referred to as "strain approach". A critical opening angle leading to crack initiation in the opposite lateral cortex was determined for each approach and was defined as comparative parameter. The relation to bone aging was investigated by considering the material parameters of cortical bones from young and old subjects. The maximum equivalent (von-Mises) stress was smaller for the cases with a drill hole at the end of the osteotomy cut. The critical angle was approximately 1.5 times higher for the specimens with a drill hole compared to those without. This corresponds to an average increase of 50%. The calculated critical angle for all approaches is below 5°. The critical angle depends on the used approach, on patient's age and assumed ductility of the cortical bone. Drilling a hole at the end of the osteotomy reduces the stresses in the lateral cortex and increases the critical opening angle prior to cracking of the opposite cortex in specimen with small correction angles. But the difference from having a drill hole or not is not so significant, especially for older patients. The ductility of the cortical bone is the decisive parameter for the critical opening angle.

Three-gradient regular solution model for simple liquids wetting complex surface topologies

PubMed Central

Akerboom, Sabine; Kamperman, Marleen

2016-01-01

Summary We use regular solution theory and implement a three-gradient model for a liquid/vapour system in contact with a complex surface topology to study the shape of a liquid drop in advancing and receding wetting scenarios. More specifically, we study droplets on an inverse opal: spherical cavities in a hexagonal pattern. In line with experimental data, we find that the surface may switch from hydrophilic (contact angle on a smooth surface θY < 90°) to hydrophobic (effective advancing contact angle θ > 90°). Both the Wenzel wetting state, that is cavities under the liquid are filled, as well as the Cassie–Baxter wetting state, that is air entrapment in the cavities under the liquid, were observed using our approach, without a discontinuity in the water front shape or in the water advancing contact angle θ. Therefore, air entrapment cannot be the main reason why the contact angle θ for an advancing water front varies. Rather, the contact line is pinned and curved due to the surface structures, inducing curvature perpendicular to the plane in which the contact angle θ is observed, and the contact line does not move in a continuous way, but via depinning transitions. The pinning is not limited to kinks in the surface with angles θkink smaller than the angle θY. Even for θkink > θY, contact line pinning is found. Therefore, the full 3D-structure of the inverse opal, rather than a simple parameter such as the wetting state or θkink, determines the final observed contact angle. PMID:27826512

Thermal Analysis of the Advanced Technology Large Aperture Space Telescope (ATLAST) 8 Meter Primary Mirror

NASA Technical Reports Server (NTRS)

Hornsby, Linda; Stahl, H. Philip; Hopkins, Randall C.

2010-01-01

The Advanced Technology Large Aperture Space Telescope (ATLAST) preliminary design concept consists of an 8 meter diameter monolithic primary mirror enclosed in an insulated, optical tube with stray light baffles and a sunshade. ATLAST will be placed in orbit about the Sun-Earth L2 and will experience constant exposure to the sun. The insulation on the optical tube and sunshade serve to cold bias the telescope which helps to minimize thermal gradients. The primary mirror will be maintained at 280K with an active thermal control system. The geometric model of the primary mirror, optical tube, sun baffles, and sunshade was developed using Thermal Desktop(R) SINDA/FLUINT(R) was used for the thermal analysis and the radiation environment was analyzed using RADCAD(R). A XX node model was executed in order to characterize the static performance and thermal stability of the mirror during maneuvers. This is important because long exposure observations, such as extra-solar terrestrial planet finding and characterization, require a very stable observatory wave front. Steady state thermal analyses served to predict mirror temperatures for several different sun angles. Transient analyses were performed in order to predict thermal time constant of the primary mirror for a 20 degree slew or 30 degree roll maneuver. This paper describes the thermal model and provides details of the geometry, thermo-optical properties, and the environment which influences the thermal performance. All assumptions that were used in the analysis are also documented. Parametric analyses are summarized for design parameters including primary mirror coatings and sunshade configuration. Estimates of mirror heater power requirements are reported. The thermal model demonstrates results for the primary mirror heated from the back side and edges using a heater system with multiple independently controlled zones.

Muscle Activity Patterns Do Not Differ Between Push-Up and Bench Press Exercises.

PubMed

Gottschall, Jinger S; Hastings, Bryce; Becker, Zachary

2018-05-29

Popular topics for upper body resistance training involve the differences between hand positions, open versus closed chain exercises, and movement variations for the novice to the advanced. We hypothesized that there will be no difference between closed (push-up) versus open (bench press) chain exercises for the primary muscle group activity nor would there be a difference between push-ups on the toes versus knees with respect to the percent contribution of each muscle. We measured surface muscle activity of 8 upper body and core muscles during a sequence of push-up and bench press variations with a normalized weight for twelve active men. Each participant completed push-ups and bench press exercises at each of three hand positions. Our results demonstrated that there were few differences between closed versus open chain exercises for the primary muscle groups with the exception of core activation. To add, in general, narrow hand positions yielded greater activation and there were no significant differences between push-ups on the toes versus knees with respect to the percent contribution for the primary muscle groups. To sum, closed chain exercises may be preferred for functional training and knee push-ups may be ideal as a novice push-up variation.

Large-Scale Noniridescent Structural Color Printing Enabled by Infiltration-Driven Nonequilibrium Colloidal Assembly.

PubMed

Bai, Ling; Mai, Van Cuong; Lim, Yun; Hou, Shuai; Möhwald, Helmuth; Duan, Hongwei

2018-03-01

Structural colors originating from interaction of light with intricately arranged micro-/nanostructures have stimulated considerable interest because of their inherent photostability and energy efficiency. In particular, noniridescent structural color with wide viewing angle has been receiving increasing attention recently. However, no method is yet available for rapid and large-scale fabrication of full-spectrum structural color patterns with wide viewing angles. Here, infiltration-driven nonequilibrium assembly of colloidal particles on liquid-permeable and particle-excluding substrates is demonstrated to direct the particles to form amorphous colloidal arrays (ACAs) within milliseconds. The infiltration-assisted (IFAST) colloidal assembly opens new possibilities for rapid manufacture of noniridescent structural colors of ACAs and straightforward structural color mixing. Full-spectrum noniridescent structural colors are successfully produced by mixing primary structural colors of red, blue, and yellow using a commercial office inkjet printer. Rapid fabrication of large-scale structural color patterns with sophisticated color combination/layout by IFAST printing is realized. The IFAST technology is versatile for developing structural color patterns with wide viewing angles, as colloidal particles, inks, and substrates are flexibly designable for diverse applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Use of repeat anterior maxillary distraction to correct residual midface hypoplasia in cleft patients.

PubMed

Richardson, Sunil; Krishna, Shreya; Bansal, Avi

2017-12-01

The study was designed to evaluate the efficacy of performing a second, repeat anterior maxillary distraction (AMD) to treat residual cleft maxillary hypoplasia. Five patients between the ages of 12 to 15 years with a history of AMD and with residual cleft maxillary hypoplasia were included in the study. Inclusion was irrespective of gender, type of cleft lip and palate, and the amount of advancement needed. Repeat AMD was executed in these patients 4 to 5 years after the primary AMD procedure to correct the cleft maxillary hypoplasia that had developed since the initial procedure. Orthopantomogram (OPG) and lateral cephalograms were taken for evaluation preoperatively, immediately after distraction, after consolidation, and one year postoperatively. The data obtained was tabulated and a Mann Whitney U-test was used for statistical comparisons. At the time of presentation, a residual maxillary hypoplasia was observed with a well maintained distraction gap on the OPG which ruled out the occurrence of a relapse. Favorable movement of the segments without any resistance was seen in all patients. Mean maxillary advancement of 10.56 mm was achieved at repeat AMD. Statistically significant increases in midfacial length, SNA angle, and nasion perpendicular to point A distance was achieved ( P =0.012, P =0.011, and P =0.012, respectively). Good profile was achieved for all patients. Minimal transient complications, for example anterior open bite and bleeding episodes, were managed. Addressing the problem of cleft maxillary hypoplasia at an early age (12-15 years) is beneficial for the child. Residual hypoplasia may develop in some patients, which may require additional corrective procedures. The results of our study show that AMD can be repeated when residual deformity develops with the previous procedure having no negative impact on the results of the repeat procedure.

Determinants of lens vault and association with narrow angles in patients from Singapore.

PubMed

Tan, Gavin S; He, Mingguang; Zhao, Wanting; Sakata, Lisandro M; Li, Jialiang; Nongpiur, Monisha E; Lavanya, Raghavan; Friedman, David S; Aung, Tin

2012-07-01

To describe the distribution and determinants of lens vault and to investigate the association of lens vault with narrow angles. Prospective cross-sectional study. Phakic subjects 50 years and older were evaluated at a primary healthcare clinic with gonioscopy, partial laser interferometry, and anterior segment optical coherence tomography (AS-OCT). Narrow angles were defined as posterior trabecular meshwork not visible for ≥2 quadrants on non-indentation gonioscopy. Lens vault was defined as the perpendicular distance between the anterior pole of the crystalline lens and the horizontal line joining the 2 scleral spurs on horizontal AS-OCT scans. Analysis of covariance, multivariate logistic regression, and area under the receiver operating characteristic curves (AUC) were performed. Of the 2047 subjects recruited, 582 were excluded because of poor image quality or inability to locate scleral spurs, leaving 1465 subjects for analysis. Eyes with narrow angles had greater lens vault compared to eyes with open angles (775.6 µm vs 386.5 µm, P < .0001). Women had significantly greater lens vault than men (497.28 µm vs 438.56 µm, P < .001), and lens vault increased significantly with age (P for trend <.001). Adjusted for age and sex, significant associations with greater lens vault were shorter axial length, shallower anterior chamber depth(ACD), higher intraocular pressure, and more hyperopic spherical equivalent (all P < .001). On multivariate analysis, subjects with lens vault >667.6 µm were more likely to have narrow angles (OR 2.201, 95% CI: 1.070-4.526) compared to those with lens vault ≤462.7 µm. The AUC for lens vault (0.816) and ACD (0.822) for detecting narrow angles were similar (P = .582). Lens vault was independently associated with narrow angles and may be useful in screening to detect eyes with narrow angles. Copyright © 2012 Elsevier Inc. All rights reserved.

How the pine seeds attach to/detach from the pine cone scale?

PubMed

Song, Kahye; Chang, Shyr-Shea; Lee, Sang Joon

2017-01-01

One of the primary purposes of pine cones is the protection and distant dispersal of pine seeds. Pine cones open and release their embedded seeds on dry and windy days for long-distance dispersal. In this study, how the pine seed attach to/ detach from the pine cone scale for efficient seed dispersal were experimentally investigated by using X-ray micro-imaging technique. The cone and seeds adhere to one another in the presence of water, which could be explained by the surface tension and the contact angle hysteresis. Otherwise, without water, the waterproof seed wing surface permits rapid drying for detach and dispersion. On the other hand, during wildfires, pine cones open their seed racks and detach the pine seeds from pine cones for rapid seed dispersal. Due to these structural advantages, pine seeds are released safely and efficiently on adjust condition. These advantageous structure could be mimicked in practical applications.

46 CFR 172.150 - Survival conditions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... waterline, in the final condition of sinkage, heel, and trim, must be below the lower edge of openings such.... (5) Side scuttles of the non-opening type. (b) Heel angle. (1) Except as described in paragraph (b)(2) of this section, the maximum angle of heel must not exceed 15 degrees (17 degrees if no part of the...

46 CFR 172.150 - Survival conditions.

Code of Federal Regulations, 2011 CFR

2011-10-01

... waterline, in the final condition of sinkage, heel, and trim, must be below the lower edge of openings such.... (5) Side scuttles of the non-opening type. (b) Heel angle. (1) Except as described in paragraph (b)(2) of this section, the maximum angle of heel must not exceed 15 degrees (17 degrees if no part of the...

Ion-damage-free planarization or shallow angle sectioning of solar cells for mapping grain orientation and nanoscale photovoltaic properties

DOE PAGES

Kutes, Yasemin; Luria, Justin; Sun, Yu; ...

2017-04-11

Ion beam milling is the most common modern method for preparing specific features for microscopic analysis, even though concomitant ion implantation and amorphization remain persistent challenges, particularly as they often modify materials properties of interest. Atomic force microscopy (AFM), on the other hand, can mechanically mill specific nanoscale regions in plan-view without chemical or high energy ion damage, due to its resolution, directionality, and fine load control. As an example, AFM-nanomilling (AFM-NM) is implemented for top-down planarization of polycrystalline CdTe thin film solar cells, with a resulting decrease in the root mean square (RMS) roughness by an order of magnitude,more » even better than for a low incidence FIB polished surface. Subsequently AFM-based property maps reveal a substantially stronger contrast, in this case of the short-circuit current or open circuit voltage during light exposure. Furthermore, electron back scattering diffraction (EBSD) imaging also becomes possible upon AFM-NM, enabling direct correlations between the local materials properties and the polycrystalline microstructure. Smooth shallow-angle cross-sections are demonstrated as well, based on targeted oblique milling. As expected, this reveals a gradual decrease in the average short-circuit current and maximum power as the underlying CdS and electrode layers are approached, but a relatively consistent open-circuit voltage through the diminishing thickness of the CdTe absorber. AFM-based nanomilling is therefore a powerful tool for material characterization, uniquely providing ion-damage free, selective area, planar smoothing or low-angle sectioning of specimens while preserving their functionality. This then enables novel, co-located advanced AFM measurements, EBSD analysis, and investigations by related techniques that are otherwise hindered by surface morphology or surface damage.« less

Ion-damage-free planarization or shallow angle sectioning of solar cells for mapping grain orientation and nanoscale photovoltaic properties

NASA Astrophysics Data System (ADS)

Kutes, Yasemin; Luria, Justin; Sun, Yu; Moore, Andrew; Aguirre, Brandon A.; Cruz-Campa, Jose L.; Aindow, Mark; Zubia, David; Huey, Bryan D.

2017-05-01

Ion beam milling is the most common modern method for preparing specific features for microscopic analysis, even though concomitant ion implantation and amorphization remain persistent challenges, particularly as they often modify materials properties of interest. Atomic force microscopy (AFM), on the other hand, can mechanically mill specific nanoscale regions in plan-view without chemical or high energy ion damage, due to its resolution, directionality, and fine load control. As an example, AFM-nanomilling (AFM-NM) is implemented for top-down planarization of polycrystalline CdTe thin film solar cells, with a resulting decrease in the root mean square (RMS) roughness by an order of magnitude, even better than for a low incidence FIB polished surface. Subsequent AFM-based property maps reveal a substantially stronger contrast, in this case of the short-circuit current or open circuit voltage during light exposure. Electron back scattering diffraction (EBSD) imaging also becomes possible upon AFM-NM, enabling direct correlations between the local materials properties and the polycrystalline microstructure. Smooth shallow-angle cross-sections are demonstrated as well, based on targeted oblique milling. As expected, this reveals a gradual decrease in the average short-circuit current and maximum power as the underlying CdS and electrode layers are approached, but a relatively consistent open-circuit voltage through the diminishing thickness of the CdTe absorber. AFM-based nanomilling is therefore a powerful tool for material characterization, uniquely providing ion-damage free, selective area, planar smoothing or low-angle sectioning of specimens while preserving their functionality. This enables novel, co-located advanced AFM measurements, EBSD analysis, and investigations by related techniques that are otherwise hindered by surface morphology or surface damage.

Hover and wind-tunnel testing of shrouded rotors for improved micro air vehicle design

NASA Astrophysics Data System (ADS)

Pereira, Jason L.

The shrouded-rotor configuration has emerged as the most popular choice for rotary-wing Micro Air Vehicles (MAVs), because of the inherent safety of the design and the potential for significant performance improvements. However, traditional design philosophies based on experience with large-scale ducted propellers may not apply to the low-Reynolds-number (˜20,000) regime in which MAVs operate. An experimental investigation of the effects of varying the shroud profile shape on the performance of MAV-scale shrouded rotors has therefore been conducted. Hover tests were performed on seventeen models with a nominal rotor diameter of 16 cm (6.3 in) and various values of diffuser expansion angle, diffuser length, inlet lip radius and blade tip clearance, at various rotor collective angles. Compared to the baseline open rotor, the shrouded rotors showed increases in thrust by up to 94%, at the same power consumption, or reductions in power by up to 62% at the same thrust. These improvements surpass those predicted by momentum theory, due to the additional effect of the shrouds in reducing the non-ideal power losses of the rotor. Increasing the lip radius and decreasing the blade tip clearance caused performance to improve, while optimal values of diffuser angle and length were found to be 10 and 50% of the shroud throat diameter, respectively. With the exception of the lip radius, the effects of changing any of the shrouded-rotor parameters on performance became more pronounced as the values of the other parameters were changed to degrade performance. Measurements were also made of the wake velocity profiles and the shroud surface pressure distributions. The uniformity of the wake was improved by the presence of the shrouds and by decreasing the blade tip clearance, resulting in lower induced power losses. For high net shroud thrust, a favorable pressure distribution over the inlet was seen to be more important than in the diffuser. Strong suction pressures were observed above the blade-passage region on the inlet surface; taking advantage of this phenomenon could enable further increases in thrust. However, trade studies showed that, for a given overall aircraft size limitation, and ignoring considerations of the safety benefits of a shroud, a larger-diameter open rotor is more likely to give better performance than a smaller-diameter shrouded rotor. The open rotor and a single shrouded-rotor model were subsequently tested at a single collective in translational flight, at angles of attack from 0° (axial flow) to 90° (edgewise flow), and at various advance ratios. In axial flow, the net thrust and the power consumption of the shrouded rotor were lower than those of the open rotor. In edgewise flow, the shrouded rotor produced greater thrust than the open rotor, while consuming less power. Measurements of the shroud surface pressure distributions illustrated the extreme longitudinal asymmetry of the flow around the shroud, with consequent pitch moments much greater than those exerted on the open rotor. Except at low airspeeds and high angles of attack, the static pressure in the wake did not reach ambient atmospheric values at the diffuser exit plane; this challenges the validity of the fundamental assumption of the simple-momentum-theory flow model for short-chord shrouds in translational flight.

Ocular Biometrics of Myopic Eyes With Narrow Angles.

PubMed

Chong, Gabriel T; Wen, Joanne C; Su, Daniel Hsien-Wen; Stinnett, Sandra; Asrani, Sanjay

2016-02-01

The purpose of this study was to compare the ocular biometrics between myopic patients with and without narrow angles. Patients with a stable myopic refraction (myopia worse than -1.00 D spherical equivalent) were prospectively recruited. Angle status was assessed using gonioscopy and biometric measurements were performed using an anterior segment optical coherence tomography and an IOLMaster. A total of 29 patients (58 eyes) were enrolled with 13 patients (26 eyes) classified as having narrow angles and 16 patients (32 eyes) classified as having open angles. Baseline demographics of age, sex, and ethnicity did not differ significantly between the 2 groups. The patients with narrow angles were on average older than those with open angles but the difference did not reach statistical significance (P=0.12). The central anterior chamber depth was significantly less in the eyes with narrow angles (P=0.05). However, the average lens thickness, although greater in the eyes with narrow angles, did not reach statistical significance (P=0.10). Refractive error, axial lengths, and iris thicknesses did not differ significantly between the 2 groups (P=0.32, 0.47, 0.15). Narrow angles can occur in myopic eyes. Routine gonioscopy is therefore recommended for all patients regardless of refractive error.

Epidemiology and clinical characteristics of patients with glaucoma: An analysis of hospital data between 2003 and 2012.

PubMed

Zhao, Yang; Fu, Jia-Li; Li, Yu-Li; Li, Ping; Lou, Feng-Lan

2015-11-01

To assess demographic and clinical characteristics of glaucoma patients in an Ophthalmologic Hospital of Jinan, China from 2003 to 2012. Medical charts of patients with primary open-angle glaucoma (POAG), primary angle closure glaucoma (PACG), and secondary glaucoma (SG) were reviewed. The main outcome measures of patients with glaucoma included basic demographic data (age at presentation, gender, and residence), clinical characteristics (admission date, intraocular pressure, and naked vision), and previous history (injury, cardiovascular disease, diabetes mellitus, hypertension, smoking, and alcohol consumption). Data from 1458 glaucoma patients were reviewed, of which PACG and SG patients accounted for 45.40% and 47.19%, respectively. The average age of all patients with glaucoma increased from 56.05 years in 2003 to 57.83 years in 2012, and the proportion of patients from rural areas rose from 46.43% to 59.13% during 10-year period. Female gender, cardiovascular disease, and hypertension were associated with PACG. POAG was related to smoking and alcohol consumption. There was positive correlation between SG and history of injury and diabetes mellitus. PACG and SG are the major types of glaucoma. Gender, injury, diabetes mellitus, cardiovascular disease, hypertension, smoking, and alcohol consumption were associated with different types of glaucoma.

Chemical applications of synchrotron radiation: Workshop report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1989-04-01

The most recent in a series of topical meetings for Advanced Photon Source user subgroups, the Workshop on Chemical Applications of Synchrotron Radiation (held at Argonne National Laboratory, October 3-4, 1988) dealt with surfaces and kinetics, spectroscopy, small-angle scattering, diffraction, and topography and imaging. The primary objectives were to provide an educational resource for the chemistry community on the scientific research being conducted at existing synchrotron sources and to indicate some of the unique opportunities that will be made available with the Advanced Photon Source. The workshop organizers were also interested in gauging the interest of chemists in the fieldmore » of synchrotron radiation. Interest expressed at the meeting has led to initial steps toward formation of a Chemistry Users Group at the APS. Individual projects are processed separately for the data bases.« less

A thermodynamic model of contact angle hysteresis.

PubMed

Makkonen, Lasse

2017-08-14

When a three-phase contact line moves along a solid surface, the contact angle no longer corresponds to the static equilibrium angle but is larger when the liquid is advancing and smaller when the liquid is receding. The difference between the advancing and receding contact angles, i.e., the contact angle hysteresis, is of paramount importance in wetting and capillarity. For example, it determines the magnitude of the external force that is required to make a drop slide on a solid surface. Until now, fundamental origin of the contact angle hysteresis has been controversial. Here, this origin is revealed and a quantitative theory is derived. The theory is corroborated by the available experimental data for a large number of solid-liquid combinations. The theory is applied in modelling the contact angle hysteresis on a textured surface, and these results are also in quantitative agreement with the experimental data.

The Effect of Suture Anchor Insertion Angle on Calcaneus Pullout Strength: Challenging the Deadman's Angle.

PubMed

Weiss, William M; Saucedo, Ramon P; Robinson, John D; Lo, Chung-Chieh Jason; Morris, Randal P; Panchbhavi, Vinod K

2017-10-01

Refractory cases of Achilles tendinopathy amenable to surgery may include reattachment of the tendon using suture anchors. However, there is paucity of information describing the optimal insertion angle to maximize the tendon footprint and anchor stability in the calcaneus. The purpose of this investigation is to compare the fixation strength of suture anchors inserted at 90° and 45° (the Deadman's angle) relative to the primary compressive trabeculae of the calcaneus. A total of 12 matched pairs of adult cadaveric calcanei were excised and potted to approximate their alignment in vivo. Each pair was implanted with 5.5-mm bioabsorbable suture anchors placed either perpendicular (90°) or oblique (45°) to the primary compressive trabeculae. A tensile load was applied until failure of anchor fixation. Differences in failure load and stiffness between anchor fixation angles were determined by paired t-tests. No significant differences were detected between perpendicular and oblique suture anchor insertion relative to primary compressive trabeculae in terms of load to failure or stiffness. This investigation suggests that the fixation strength of suture anchors inserted perpendicular to the primary compression trabeculae and at the Deadman's angle are possibly comparable. Biomechanical comparison study.

Energy Landscapes for the Self-Assembly of Supramolecular Polyhedra

NASA Astrophysics Data System (ADS)

Russell, Emily R.; Menon, Govind

2016-06-01

We develop a mathematical model for the energy landscape of polyhedral supramolecular cages recently synthesized by self-assembly (Sun et al. in Science 328:1144-1147, 2010). Our model includes two essential features of the experiment: (1) geometry of the organic ligands and metallic ions; and (2) combinatorics. The molecular geometry is used to introduce an energy that favors square-planar vertices (modeling {Pd}^{2+} ions) and bent edges with one of two preferred opening angles (modeling boomerang-shaped ligands of two types). The combinatorics of the model involve two-colorings of edges of polyhedra with four-valent vertices. The set of such two-colorings, quotiented by the octahedral symmetry group, has a natural graph structure and is called the combinatorial configuration space. The energy landscape of our model is the energy of each state in the combinatorial configuration space. The challenge in the computation of the energy landscape is a combinatorial explosion in the number of two-colorings of edges. We describe sampling methods based on the symmetries of the configurations and connectivity of the configuration graph. When the two preferred opening angles encompass the geometrically ideal angle, the energy landscape exhibits a very low-energy minimum for the most symmetric configuration at equal mixing of the two angles, even when the average opening angle does not match the ideal angle.

Satellite-Tracking Millimeter-Wave Reflector Antenna System For Mobile Satellite-Tracking

NASA Technical Reports Server (NTRS)

Densmore, Arthur C. (Inventor); Jamnejad, Vahraz (Inventor); Woo, Kenneth E. (Inventor)

2001-01-01

A miniature dual-band two-way mobile satellite-tracking antenna system mounted on a movable vehicle includes a miniature parabolic reflector dish having an elliptical aperture with major and minor elliptical axes aligned horizontally and vertically, respectively, to maximize azimuthal directionality and minimize elevational directionality to an extent corresponding to expected pitch excursions of the movable ground vehicle. A feed-horn has a back end and an open front end facing the reflector dish and has vertical side walls opening out from the back end to the front end at a lesser horn angle and horizontal top and bottom walls opening out from the back end to the front end at a greater horn angle. An RF circuit couples two different signal bands between the feed-horn and the user. An antenna attitude controller maintains an antenna azimuth direction relative to the satellite by rotating it in azimuth in response to sensed yaw motions of the movable ground vehicle so as to compensate for the yaw motions to within a pointing error angle. The controller sinusoidally dithers the antenna through a small azimuth dither angle greater than the pointing error angle while sensing a signal from the satellite received at the reflector dish, and deduces the pointing angle error from dither-induced fluctuations in the received signal.

A satellite-tracking millimeter-wave reflector antenna system for mobile satellite-tracking

NASA Technical Reports Server (NTRS)

Densmore, Arthur C. (Inventor); Jamnejad, Vahraz (Inventor); Woo, Kenneth E. (Inventor)

1995-01-01

A miniature dual-band two-way mobile satellite tracking antenna system mounted on a movable ground vehicle includes a miniature parabolic reflector dish having an elliptical aperture with major and minor elliptical axes aligned horizontally and vertically, respectively, to maximize azimuthal directionality and minimize elevational directionality to an extent corresponding to expected pitch excursions of the movable ground vehicle. A feed-horn has a back end and an open front end facing the reflector dish and has vertical side walls opening out from the back end to the front end at a lesser horn angle and horizontal top and bottom walls opening out from the back end to the front end at a greater horn angle. An RF circuit couples two different signal bands between the feed-horn and the user. An antenna attitude controller maintains an antenna azimuth direction relative to the satellite by rotating it in azimuth in response to sensed yaw motions of the movable ground vehicle so as to compensate for the yaw motions to within a pointing error angle. The controller sinusoidally dithers the antenna through a small azimuth dither angle greater than the pointing error angle while sensing a signal from the satellite received at the reflector dish, and deduces the pointing angle error from dither-induced fluctuations in the received signal.

Characteristics of Upper Quadrant Posture of Young Women with Temporomandibular Disorders

PubMed Central

Uritani, Daisuke; Kawakami, Tetsuji; Inoue, Tomohiro; Kirita, Tadaaki

2014-01-01

[Purpose] This study aimed to investigate the characteristics of upper quadrant posture of young women with temporomandibular disorders. [Subjects] The participants were 19 female patients with temporomandibular disorders (patient group: mean age, 30.1 years) and 14 controls (control group: mean age, 24.6 years). [Methods] Outcome measures were the neck inclination angle (formed by a line connecting C7 and the ear tragus with a horizontal line), the angle of the shoulder (formed by a line connecting C7 and the acromial angle with a horizontal line), the cranial rotation angle (formed by a line connecting the ear tragus and the corner of the eye with a horizontal line), and the neck-length/shoulder-width ratio [the ratio of the neck length (from C7 to the tragus) to the width of the shoulder between the acromial angle]. The maximum range of mouth opening was measured using a scale. [Results] The neck inclination angle and maximum range of mouth opening were significantly smaller in the patient group than in the control group. No significant differences were observed in the other outcome measures between the two groups. [Conclusion] Temporomandibular disorders with limited mouth opening in young females are associated with the head position relative to the trunk. PMID:25276038

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldstein, Adam; Connaughton, Valerie; Briggs, Michael S.

We present a method to estimate the jet opening angles of long duration gamma-ray bursts (GRBs) using the prompt gamma-ray energetics and an inversion of the Ghirlanda relation, which is a correlation between the time-integrated peak energy of the GRB prompt spectrum and the collimation-corrected energy in gamma-rays. The derived jet opening angles using this method and detailed assumptions match well with the corresponding inferred jet opening angles obtained when a break in the afterglow is observed. Furthermore, using a model of the predicted long GRB redshift probability distribution observable by the Fermi Gamma-ray Burst Monitor (GBM), we estimate themore » probability distributions for the jet opening angle and rest-frame energetics for a large sample of GBM GRBs for which the redshifts have not been observed. Previous studies have only used a handful of GRBs to estimate these properties due to the paucity of observed afterglow jet breaks, spectroscopic redshifts, and comprehensive prompt gamma-ray observations, and we potentially expand the number of GRBs that can be used in this analysis by more than an order of magnitude. In this analysis, we also present an inferred distribution of jet breaks which indicates that a large fraction of jet breaks are not observable with current instrumentation and observing strategies. We present simple parameterizations for the jet angle, energetics, and jet break distributions so that they may be used in future studies.« less

Association of iris crypts with acute primary angle closure.

PubMed

Koh, Victor; Chua, Jacqueline; Shi, Yuan; Thakku, Sri Gowtham; Lee, Ryan; Nongpiur, Monisha E; Baskaran, Mani; Kumar, Rajesh S; Perera, Shamira; Aung, Tin; Cheng, Ching-Yu

2017-10-01

To determine the relationship between iris surface features and acute primary angle closure (APAC) in eyes with angle closure. Case-control study involving Asian patients diagnosed with previous APAC, primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG) at an eye centre in Singapore between August 2012 and January 2015. Participants underwent ophthalmic examination and digital slit-lamp iris photography. Iris surface features were graded based on crypts, furrows and colour. Fellow eyes of APAC were compared with PACS and PAC/PACG eyes with regard to their iris surface features. Occurrence of APAC. A total of 309 patients (71 APAC, 139 PACS, 47 PAC and 52 PACG) were included (mean age: 67.7±7.2 years and 36.6% male). Compared with PACS, higher crypt grade was significantly associated with lower odds of APAC (OR=0.58 for one grade higher in crypt grade; p=0.027, adjusted for age, gender, ethnicity and pupil diameter). The results remained similar when compared with PAC/PACG group (OR=0.58 for one grade higher in crypt grade; p=0.043). We did not observe any significant associations between iris furrows or colour with presence of APAC. Our study comprising Asian eyes with angle closure suggests that the presence of a higher crypt grading may be protective for APAC. As such, assessing iris surface architecture for crypts could be a new measure for risk stratification of developing APAC in eyes with angle closure. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Gonioscopy findings and prevalence of occludable angles in a Burmese population: the Meiktila Eye Study.

PubMed

Casson, R J; Newland, H S; Muecke, J; McGovern, S; Abraham, L M; Shein, W K; Selva, D; Aung, T

2007-07-01

To determine the prevalence of preglaucomatous angle-closure disease in central Myanmar. A population-based survey of inhabitants >or=40 years in the Meiktila District was carried out; 2481 subjects were identified, 2076 participated and 2060 underwent gonioscopy of at least one eye. Eyes with angles traditionally described as "occludable" were recorded as primary angle-closure suspects (PACS); eyes with PACS and peripheral anterior synechiae (PAS), or an increased intraocular pressure but without primary angle-closure glaucoma, were recorded as primary angle closure (PAC). The prevalence of PACS in at least one eye was 5.7% (95% CI 4.72 to 6.62); prevalence increased with age and was more common in women (p<0.001). The prevalence of PAC in at least one eye was 1.50% (95% CI 1.47 to 1.53). All participants with PAS had at least 90 degrees of closure (range 90-360 degrees). The prevalence of preglaucomatous angle-closure disease (PACS and PAC) in this population was 5.7% and 1.5%, respectively. PACS was more common in women, and its prevalence increased with age.

Techniques for enhancing durability and equivalence ratio control in a rich-lean, three-stage ground power gas turbine combustor

NASA Technical Reports Server (NTRS)

Schultz, D. F.

1982-01-01

Rig tests of a can-type combustor were performed to demonstrate two advanced ground power engine combustor concepts: steam cooled rich-burn combustor primary zones for enhanced durability; and variable combustor geometry for three stage combustion equivalence ratio control. Both concepts proved to be highly successful in achieving their desired objectives. The steam cooling reduced peak liner temperatures to less than 800 K. This offers the potential of both long life and reduced use of strategic materials for liner fabrication. Three degrees of variable geometry were successfully implemented to control airflow distribution within the combustor. One was a variable blade angle axial flow air swirler to control primary airflow while the other two consisted of rotating bands to control secondary and tertiary or dilution air flow.

A Technical Overview and Description of SOFIA (Stratospheric Observatory for Infrared Astronomy)

NASA Technical Reports Server (NTRS)

Kunz, Nans

2003-01-01

This paper provides a technical overview of SOFIA, a unique airborne observatory, from an engineering perspective. It will do this by describing several of the systems of this observatory that are common with mountain top ground based observatories but mostly emphasize those more unique features and systems that are required to facilitate world class astronomy from a highly modified Boeing 747-SP flying at Mach 0.84 in the Stratosphere. This paper provides a technical overview of SOFIA by reviewing each of the performance specifications (the level one requirements for development) and describing some of the technical advancements for the telescope as well as the platform required to achieve these performance specifications. The technical advancements involved include mirror technologies, control system features, the telescope suspension system, and the aircraft open port cavity with associated cavity door that opens in flight and tracks the telescope elevation angle. For background this paper will provide a brief programmatic overview of the SOFIA project including the joint project arrangement between the US and Germany (NASA and DLR). Additionally, this paper will describe the up to date status of the development of SOFIA as the Observatory nears the date of the first test flight in the summer of 2004.

Investigation of pH response and photo-control of wettability on spiropyran-derivatized surfaces

NASA Astrophysics Data System (ADS)

Park, Choong-Do

2009-12-01

One promising method to control a liquid drop on a surface for microfluidic devices is to use the surface tension gradient on a photo-responsive surface by light irradiation. A photo-switchable spiropyran monolayer was prepared on smooth glass or silicon wafers via 3-aminopropylmethyldiethoxysilane linkages. The pH response of the surface-bound spiropyran was investigated by measuring contact angle as a function of pH, since the pH value of the liquids applied to a microfluidic system can vary widely. Based on the contact angle titration and UV-Vis spectroscopic data, a protonation and deprotonation mechanism of the surface-bound spiropyran was proposed. The advancing contact angles under UV and under visible light irradiation at high pH values were about 100 smaller than those at low pH values. The decrease in contact angle under UV light with decreasing pH value was assigned to the protonation of open merocyanine (MC) to MC-OH+. Meanwhile, the decrease in contact angle under visible light was attributed to the protonation of the closed spiropryan (SP), generating a mixed state of MC-OH+ in equilibrium with N-protonated SP-NH+. In order to examine the possibility of light-induced liquid drop motion on the spiropyran-derivatized smooth surfaces, the light-induced surface tension change between SP and MC was estimated using the contact angle hysteresis (CAH) and the Lifshitz---van der Waals/Acid-Base (LWAB) approaches based on the contact angle data. The average light-induced surface energy change between the two isomers under UV and visible light exposure was 1.4 mJ/m 2, implying that the small change in surface tension is not sufficient to move a liquid droplet on the surface. Liquid drop motion requires that the light-induced switching angle be greater than the contact angle hysteresis. However, the light-induced switching angle of the spiropyran-derivatized surface was significantly smaller than the hysteresis. Thus, in order to achieve liquid drop motion on the spiropyran-derivatized surface, a new surface design which employs a combination of chemical modification of a hydrophobic organosilane and micropatterned rough surface morphology was suggested.

Cross Cell Sandwich Core

NASA Technical Reports Server (NTRS)

Ford, Donald B. (Inventor)

2004-01-01

A sandwich core comprises two faceplates separated by a plurality of cells. The cells are comprised of walls positioned at oblique angles relative to a perpendicular axis extending through the faceplates. The walls preferably form open cells and are constructed from open cells and are constructed from rows of ribbons. The walls may be obliquely angled relative to more than one plane extending through the perpendicular axis.

Heterogeneous growth-induced prestrain in the heart

PubMed Central

Genet, M.; Rausch, M.; Lee, L.C.; Choy, S.; Zhao, X.; Kassab, G.S.; Kozerke, S.; Guccione, J.M.; Kuhl, E.

2015-01-01

Even when entirely unloaded, biological structures are not stress-free, as shown by Y.C. Fung’s seminal opening angle experiment on arteries and the left ventricle. As a result of this prestrain, subject-specific geometries extracted from medical imaging do not represent an unloaded reference configuration necessary for mechanical analysis, even if the structure is externally unloaded. Here we propose a new computational method to create physiological residual stress fields in subject-specific left ventricular geometries using the continuum theory of fictitious configurations combined with a fixed-point iteration. We also reproduced the opening angle experiment on four swine models, to characterize the range of normal opening angle values. The proposed method generates residual stress fields which can reliably reproduce the range of opening angles between 8.7±1.8 and 16.6 ± 13.7 as measured experimentally. We demonstrate that including the effects of prestrain reduces the left ventricular stiffness by up to 40%, thus facilitating the ventricular filling, which has a significant impact on cardiac function. This method can improve the fidelity of subject-specific models to improve our understanding of cardiac diseases and to optimize treatment options. PMID:25913241

Refraction and scattering of sound by a shear layer

NASA Technical Reports Server (NTRS)

Schlinker, R. H.; Amiet, R. K.

1980-01-01

The angle and amplitude changes for acoustic waves refracted by a circular open jet shear layer were determined. The generalized refraction theory was assessed experimentally for on axis and off axis acoustic source locations as source frequency varied from 1 kHz to 10 kHz and free stream Mach number varied from 0.1 to 0.4. Angle and amplitude changes across the shear layer show good agreement with theory. Experiments confirm that the refraction theory is independent of shear layer thickness, acoustic source frequency, and source type. A generalized theory is, thus, available for correcting far field noise data acquired in open jet test facilities. The effect of discrete tone scattering by the open jet turbulent shear layer was also studied. Scattering effects were investigated over the same Mach number range as frequency varied from 5 kHz to 15 kHz. Attenuation of discrete tone amplitude and tone broadening were measured as a function of acoustic source position and radiation angle. Scattering was found to be stronger at angles close to the open jet axis than at 90 deg, and becomes stronger as the acoustic source position shifts downstream. A scattering analysis provided an estimate of the onset of discrete tone scattering.

Retrobulbar hemodynamic parameters in men and women with open angle glaucoma.

PubMed

Marjanović, Ivan; Marjanović, Marija; Gvozdenović, Ranko; Risović, Dušica

2014-12-01

Several factors may have influence on systemic circulation. Additionally, peripheral circulation also demonstrates sex differences, in young women presenting significantly lower finger blood flow in comparison to men of the same age, a finding that disappears in women after menopause. The aim of this study was to compare the retrobulbar hemodynamic parameters measured by means of color Doppler imaging in women and men with open-angle glaucoma and elevated intraocular pressure. A total of 52 eyes from 52 open-angle glaucoma (OAG) patients, with elevated intraocular pressure (lOP), were included in this cross-sectional study. Peak-systolic velocity (PSV), end-diastolic velocity (EDV), and Pourcelot resistivity index (RI) were assessed in the ophtalmic artery (OA), central retinal artery (CRA), and posterior cilliary arteries (PCA). IOP was measured both with Goldmann Applanation tonometer (GAT) and with the dynamic contour tonometer (DCT), three times respectively. Ocular pulse amplitude (OPA) appeared during the DCT measurement. The retrobulbar hemodynamic parameters did not show any difference between men and post-menopausal women. The results of our study did not find any difference between sexes in patients with open-angle glaucoma and elevated intraocular pressure.

Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case.

PubMed

Ao, Dongyang; Li, Yuanhao; Hu, Cheng; Tian, Weiming

2017-12-22

The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures.

Accurate Analysis of Target Characteristic in Bistatic SAR Images: A Dihedral Corner Reflectors Case

PubMed Central

Ao, Dongyang; Hu, Cheng; Tian, Weiming

2017-01-01

The dihedral corner reflectors are the basic geometric structure of many targets and are the main contributions of radar cross section (RCS) in the synthetic aperture radar (SAR) images. In stealth technologies, the elaborate design of the dihedral corners with different opening angles is a useful approach to reduce the high RCS generated by multiple reflections. As bistatic synthetic aperture sensors have flexible geometric configurations and are sensitive to the dihedral corners with different opening angles, they specially fit for the stealth target detections. In this paper, the scattering characteristic of dihedral corner reflectors is accurately analyzed in bistatic synthetic aperture images. The variation of RCS with the changing opening angle is formulated and the method to design a proper bistatic radar for maximizing the detection capability is provided. Both the results of the theoretical analysis and the experiments show the bistatic SAR could detect the dihedral corners, under a certain bistatic angle which is related to the geometry of target structures. PMID:29271917

--No Title--

Science.gov Websites

: "\\f106"; /* open - switch to fa-angle-up */ } @media(min-width:768px) { /* top level open */ } } /* top level open hover */ .navbar-dark .navbar-nav > li.open > a:hover, .navbar-dark .navbar-nav :768px) { /* top level open hover desktop*/ .navbar-dark .navbar-nav > li.open > a:hover, .navbar

Controlled five-year follow-up study of laser trabeculoplasty as primary therapy for open-angle glaucoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuulonen, A.; Niva, A.K.; Alanko, H.I.

1987-10-15

We followed up 32 eyes of 32 patients with early glaucoma (22 with capsular glaucoma and ten with simple glaucoma) who received laser trabeculoplasty as a primary therapy. These eyes were compared with a matched control group of 32 eyes treated with medication initially. The success rate (intraocular pressure below 22 mm Hg with laser alone or medication alone) at five years was 50% (16 of 32 eyes) in the laser-treated group and 22% (seven of 32 eyes) in the control group (P less than .02). The control group required more modifications of their therapy to control intraocular pressure. Themore » neuroretinal rim area in the control eyes decreased 2.5 times as much as in the laser group (P = .017). Changes in the Friedmann visual fields did not differ significantly between the two groups.« less

Reinterventions after open and endovascular AAA repair.

PubMed

Malina, M

2015-04-01

Reinterventions seem to occur more frequently after endovascular aneurysm repair than after open surgical repair and are encountered in about 20% versus 10% of the cases, respectively. However, reinterventions following endovascular repair are predominantly endoluminal and early reinterventions are more frequent after open repair. The indications for reintervention after EVAR have changed over time. The incidence and type of reintervention depends on the complexity of the primary procedure, irrespective of whether it was open or endovascular. The use of a device outside instructions for use is associated with a higher complication rate but it may nevertheless be fully justified. Advanced stent-grafts such as fenestrated and branched devices require secondary procedures more often than a standard stent-graft. Similarly, more complex open repair, e.g. a bifurcated bypass, reimplantation of visceral arteries or a redo procedure, is also associated with more reinterventions than a simple tube graft. This manuscript presents some of the most common complications of open and endovascular aortic aneurysm repair and the reinterventions they require. Many of the complications are similar with both open and endovascular techniques. Limb thrombosis, infections and endoleaks are the most frequent indications for reintervention.

A new multi-angle remote sensing framework for scaling vegetation properties from tower-based spectro-radiometers to next generation "CubeSat"-satellites.

NASA Astrophysics Data System (ADS)

Hilker, T.; Hall, F. G.; Dyrud, L. P.; Slagowski, S.

2014-12-01

Frequent earth observations are essential for assessing the risks involved with global climate change, its feedbacks on carbon, energy and water cycling and consequences for live on earth. Often, satellite-remote sensing is the only practical way to provide such observations at comprehensive spatial scales, but relationships between land surface parameters and remotely sensed observations are mostly empirical and cannot easily be scaled across larger areas or over longer time intervals. For instance, optically based methods frequently depend on extraneous effects that are unrelated to the surface property of interest, including the sun-server geometry or background reflectance. As an alternative to traditional, mono-angle techniques, multi-angle remote sensing can help overcome some of these limitations by allowing vegetation properties to be derived from comprehensive reflectance models that describe changes in surface parameters based on physical principles and radiative transfer theory. Recent results have shown in theoretical and experimental research that multi-angle techniques can be used to infer and scale the photosynthetic rate of vegetation, its biochemical and structural composition robustly from remote sensing. Multi-angle remote sensing could therefore revolutionize estimates of the terrestrial carbon uptake as scaling of primary productivity may provide a quantum leap in understanding the spatial and temporal complexity of terrestrial earth science. Here, we introduce a framework of next generation tower-based instruments to a novel and unique constellation of nano-satellites (Figure 1) that will allow us to systematically scale vegetation parameters from stand to global levels. We provide technical insights, scientific rationale and present results. We conclude that future earth observation from multi-angle satellite constellations, supported by tower based remote sensing will open new opportunities for earth system science and earth system modeling.

Tip-path-plane angle effects on rotor blade-vortex interaction noise levels and directivity

NASA Technical Reports Server (NTRS)

Burley, Casey L.; Martin, Ruth M.

1988-01-01

Acoustic data of a scale model BO-105 main rotor acquired in a large aeroacoustic wind tunnel are presented to investigate the parametric effects of rotor operating conditions on blade-vortex interaction (BVI) impulsive noise. Contours of a BVI noise metric are employed to quantify the effects of rotor advance ratio and tip-path-plane angle on BVI noise directivity and amplitude. Acoustic time history data are presented to illustrate the variations in impulsive characteristics. The directionality, noise levels and impulsive content of both advancing and retreating side BVI are shown to vary significantly with tip-path-plane angle and advance ratio over the range of low and moderate flight speeds considered.

In-flight measurement of propeller noise on the fuselage of an airplane

NASA Technical Reports Server (NTRS)

Pla, Frederic G.; Ranaudo, Richard; Woodward, Richard P.

1989-01-01

In-flight measurements of propeller noise on the fuselage of an OV-10A aircraft were obtained using a horizontal and a vertical microphone array. A wide range of flight conditions were tested including changes in angle of attack, sideslip angle, power coefficient, helical tip Mach number and advance ratio, and propeller direction of rotation. Results show a dependence of the level and directivity of the tones on the angle of attack and on the sideslip angle with the propeller direction of rotation, which is similar to results obtained in wind tunnel tests with advanced propeller designs. The level of the tones at each microphone increases with increasing angle of attack for inboard-down propeller rotation and decreases for inboard-up rotation. The level also increases with increasing slideslip angle for both propeller directions of rotation. Increasing the power coefficient results in a slight increase in the level of the tones. A strong shock wave is generated by the propeller blades even at relatively low helical tip Mach numbers resulting in high harmonic levels. As the helical tip Mach number and the advance ratio are increased, the level of the higher harmonics increases much faster than the level of the blade passage frequency.

Aerodynamic Load Measurements and Opening Characteristics of Automatic Leading Edge Slats on a 45 deg Sweptback Wing at Transonic Speeds

NASA Technical Reports Server (NTRS)

Arabian, Donald D.; Runckel, Jack F.; Reid, Charles F, Jr.

1961-01-01

Measurements of the normal force and chord force were made on the slats of a sting-mounted wing-fuselage model through a Mach number range of 0.60 to 1.03 and at angles of attack from 0 to 20 deg at subsonic speeds and from 0 to 8 deg at Mach number 1.03. The 20-percent-chord tapered leading-edge slats extended from 25 to 95 percent of the semispan and consisted of five segments. The model wing had 45 deg sweep, an aspect ratio of 3.56, a taper ratio of 0.3, and NACA 64(06)AO07 airfoil sections. Slat forces and moments were determined for the slats in the almost-closed and open positions for spanwise extents of 35 to 95 percent and 46 to 95 percent of the semispan. The results of the investigation showed little change in the slat maximum force and moment coefficients with Mach number. The coefficients for the open and almost-closed slat positions had similar variations with angle of attack. The loads on the individual slat segments were found to increase toward the tip for moderate angles of attack and decrease toward the tip for high angles of attack. An analysis of the opening and closing characteristics of aerodynamically operated slats opening on a circular-arc path is included.

A mechanical analysis of conduit arteries accounting for longitudinal residual strains.

PubMed

Wang, Ruoya; Gleason, Rudolph L

2010-04-01

Identification of an appropriate stress-free reference configuration is critically important in providing a reasonable prediction of the intramural stress distribution when performing biomechanical analyses on arteries. The stress-free state is commonly approximated as a radially cut ring that typically opens into a nearly circular sector, relieving much of the circumferential residual strains that exist in the traction-free configuration. An opening angle is often used to characterize this sector. In this study, we first present experimental results showing significant residual deformations in the longitudinal direction of two commonly studied arteries in the pig: the common carotid artery and the left anterior descending coronary artery. We concluded that a radially cut ring cannot completely describe the stress-free state of the arteries. Instead, we propose the use of a longitudinal opening angle, in conjunction with the traditional circumferential opening angle, to experimentally quantify the stress-free state of an artery. Secondly, we propose a new kinematic model to account for the addition of longitudinal residual strains through employing the longitudinal opening angle and performed a stress analysis. We found that with the inclusion of longitudinal residual strains in the stress analysis, the predicted circumferential stress gradient was decreased by 3-fold and the predicted longitudinal stress gradient was increased by 5.7-fold. Thus, inclusion of longitudinal residual strains has a significant effect on the predicted stress distribution in arteries.

Drop rebound after impact: the role of the receding contact angle.

PubMed

Antonini, C; Villa, F; Bernagozzi, I; Amirfazli, A; Marengo, M

2013-12-31

Data from the literature suggest that the rebound of a drop from a surface can be achieved when the wettability is low, i.e., when contact angles, measured at the triple line (solid-liquid-air), are high. However, no clear criterion exists to predict when a drop will rebound from a surface and which is the key wetting parameter to govern drop rebound (e.g., the "equilibrium" contact angle, θeq, the advancing and the receding contact angles, θA and θR, respectively, the contact angle hysteresis, Δθ, or any combination of these parameters). To clarify the conditions for drop rebound, we conducted experimental tests on different dry solid surfaces with variable wettability, from hydrophobic to superhydrophobic surfaces, with advancing contact angles 108° < θA < 169° and receding contact angles 89° < θR < 161°. It was found that the receding contact angle is the key wetting parameter that influences drop rebound, along with surface hydrophobicity: for the investigated impact conditions (drop diameter 2.4 < D0 < 2.6 mm, impact speed 0.8 < V < 4.1 m/s, Weber number 25 < We < 585), rebound was observed only on surfaces with receding contact angles higher than 100°. Also, the drop rebound time decreased by increasing the receding contact angle. It was also shown that in general care must be taken when using statically defined wetting parameters (such as advancing and receding contact angles) to predict the dynamic behavior of a liquid on a solid surface because the dynamics of the phenomenon may affect surface wetting close to the impact point (e.g., as a result of the transition from the Cassie-Baxter to Wenzel state in the case of the so-called superhydrophobic surfaces) and thus affect the drop rebound.

Oral administration of forskolin and rutin contributes to intraocular pressure control in primary open angle glaucoma patients under maximum tolerated medical therapy.

PubMed

Vetrugno, Michele; Uva, Maurizio G; Russo, Vincenzo; Iester, Michele; Ciancaglini, Marco; Brusini, Paolo; Centofanti, Marco; Rossetti, Luca M

2012-10-01

Tight control of intraocular pressure (IOP) is still the only therapeutic approach available for the treatment of primary open angle glaucoma (POAG). However, some patients do not respond adequately to hypotonising drugs, and despite multiple drug combinations they cannot reach their target IOP. Forskolin is a natural compound that has already shown efficacy in IOP reduction following topical application. The aim of this study was to evaluate the effects on the IOP of a food supplement containing forskolin and rutin when administered to POAG patients under maximum tolerated medical therapy (MTMT) and on a waiting list for filtrating surgery to further decrease their IOP. The design of the study was open and case-controlled. Ninety-seven (52 in the treatment group, and 45 in the reference group) patients were enrolled in 8 different glaucoma centers in Italy, all under MTMT and with IOP enrollment values above their target pressure. During the 30 days before surgery, patients in the treatment group were prescribed 2 tablets per day of a food supplement containing rutin and forskolin in addition to their usual topical drug treatment. Their IOP values were measured at 3 time points during the day, at enrollment and once a week until surgery. Control patients continued only with their normal topical therapy. All patients in the treatment group, independently of the combination drug therapy that they were taking, showed a further 10% decrease (P<0.01) of their IOP, starting from 1 week after introduction of the oral supplement and lasting until the last evaluation before surgery. This decrease was more evident (15% of the enrollment value; P<0.01) in those subjects with high (IOP≥21 mmHg) enrollment values rather than in those with low (IOP<21) enrollment values (9%; P<0.01). On the contrary, IOP values in the control group remained stable from the beginning to the end of the observation period, independently of their enrollment values. Forskolin and rutin given as oral treatment appear to contribute to a better control and a further small reduction of IOP in patients who were poorly responsive to multitherapy treatment.

Multicenter, Randomized, Controlled Study Comparing Tafluprost/Timolol Fixed Combination with Latanoprost/Timolol Fixed Combination in Primary Open-Angle Glaucoma and Ocular Hypertension.

PubMed

Suzuki, Katsuyoshi; Otsuka, Naomi; Hizaki, Hiroko; Hashimoto, Masayo; Kuwayama, Yasuaki

2018-06-05

This was the first exploratory randomized controlled study to compare the efficacy and safety of a preserved tafluprost/timolol fixed combination (TAF/TIM) with a preserved latanoprost/timolol fixed combination (LAT/TIM). This prospective, randomized, open-label study was conducted in Japanese patients with primary open-angle glaucoma, including normal-tension glaucoma or ocular hypertension. Following a 4-week LAT/TIM run-in period, eligible patients entered a 12-week treatment period, during which they received either LAT/TIM or TAF/TIM. The efficacy endpoint was the change in intraocular pressure (IOP) from baseline to week 12 and the safety endpoints included the changes from baseline to week 12 in superficial punctate keratopathy (SPK) score, tear breakup time (TBUT), and hyperemia score, as well as adverse events (AEs). At week 6, ocular symptoms were evaluated using a questionnaire. In total, 131 patients provided informed consent. Of these, 115 completed the run-in period and were assigned to receive TAF/TIM (n = 60) or LAT/TIM (n = 55). At week 12, there were no significant differences between the TAF/TIM and LAT/TIM groups in the change from baseline in trough IOP and IOP at 4-6 h after instillation. There were no significant differences between the two groups in the change from baseline to week 12 in SPK score, TBUT, and hyperemia score. However, only in the TAF/TIM group, the total SPK score and the inferior cornea SPK score were significantly lower at week 12 compared with baseline. Eye irritation and eye pain were significantly decreased in the TAF/TIM group compared with the LAT/TIM group. Two treatment-related AEs were reported in the TAF/TIM group (3.3%) and none in the LAT/TIM group, while no serious AEs were reported in either group. TAF/TIM is as effective as LAT/TIM in terms of IOP-reducing effect, with fewer ocular symptoms. TAF/TIM was associated with a significant improvement in SPK scores. UMIN Clinical Trials Registry Identifier, UMIN000023862. Santen Pharmaceutical Co., Ltd., Osaka, Japan.

An Innovate Robotic Endoscope Guidance System for Transnasal Sinus and Skull Base Surgery: Proof of Concept.

PubMed

Friedrich, D T; Sommer, F; Scheithauer, M O; Greve, J; Hoffmann, T K; Schuler, P J

2017-12-01

Objective  Advanced transnasal sinus and skull base surgery remains a challenging discipline for head and neck surgeons. Restricted access and space for instrumentation can impede advanced interventions. Thus, we present the combination of an innovative robotic endoscope guidance system and a specific endoscope with adjustable viewing angle to facilitate transnasal surgery in a human cadaver model. Materials and Methods  The applicability of the robotic endoscope guidance system with custom foot pedal controller was tested for advanced transnasal surgery on a fresh frozen human cadaver head. Visualization was enabled using a commercially available endoscope with adjustable viewing angle (15-90 degrees). Results  Visualization and instrumentation of all paranasal sinuses, including the anterior and middle skull base, were feasible with the presented setup. Controlling the robotic endoscope guidance system was effectively precise, and the adjustable endoscope lens extended the view in the surgical field without the common change of fixed viewing angle endoscopes. Conclusion  The combination of a robotic endoscope guidance system and an advanced endoscope with adjustable viewing angle enables bimanual surgery in transnasal interventions of the paranasal sinuses and the anterior skull base in a human cadaver model. The adjustable lens allows for the abandonment of fixed-angle endoscopes, saving time and resources, without reducing the quality of imaging.

Ab Interno Trabeculectomy With the Trabectome as a Valuable Therapeutic Option for Failed Filtering Blebs.

PubMed

Wecker, Thomas; Neuburger, Matthias; Bryniok, Laura; Bruder, Kathrin; Luebke, Jan; Anton, Alexandra; Jordan, Jens F

2016-09-01

Uncontrolled intraocular pressure (IOP) after glaucoma filtration surgery is a challenging problem in the management of glaucoma patients. The Trabectome is a device for selective electroablation of the trabecular meshwork through a clear cornea incision without affecting the conjunctiva. Minimally invasive glaucoma surgery using the Trabectome is safe and effective as primary glaucoma surgery. Here we investigate the results of ab interno trabeculectomy with the Trabectome for IOP control in patients with a failed filtering bleb. A total of 60 eyes of 60 consecutive patients with primary open-angle glaucoma (POAG) or pseudoexfoliative glaucoma (PXG) were enrolled in this single center observational study. Trabectome surgery was performed alone or in combination with phacoemulsification by 2 experienced surgeons. IOP readings and number of IOP lowering medication as primary outcome parameters were taken by an independent examiner. Intraoperative and postoperative medication were recorded systematically. Mean IOP before surgery was 24.5±3.5 mm Hg and decreased to 15.7±3.4 (-36%) after mean follow-up of 415 days. The number of necessary IOP lowering medication dropped from 2.1±1.3 to 1.8±1.2 (14% reduction from baseline). A total of 25% (n=15) of cases reported here needed additional surgery after 517 days (range: 6 to 1563 d). No major complications were observed. After mean follow-up, we found a qualified success rate for PXG of 87% and 50% for POAG as revealed by the Kaplan-Meier analysis according to the definitions for success in advanced glaucoma cases according to the World Glaucoma Association (40% reduction from baseline IOP and maximum IOP of 15 mm Hg). Trabectome surgery for uncontrolled IOP after trabeculectomy is safe and effective especially in PXG patients. Given the demanding subgroup of patients studied here, it is not surprising that success rates are lower compared with previous studies investigating the Trabectome for primary glaucoma surgery. The number of necessary IOP lowering medication drops at first, but seems to reach preoperative values after 20 months of follow-up. Trabectome surgery should be considered as a valuable escape procedure for patients with failed filtering blebs and uncontrolled IOP.

Uveal effusion following acute primary angle-closure: a retrospective case series

PubMed Central

Yang, Jian-Gang; Li, Jian-Jun; Tian, Hua; Li, Yan-Hong; Gong, Yu-Jing; Su, An-Le; He, Na

2017-01-01

AIM To evaluate the morphological changes in anterior segment in Chinese patients with uveal effusion (UE) after the attack of acute primary angle-closure (APAC) using ultrasound biomicroscopy (UBM), and to assess the clinical course and prognosis of the disease. METHODS In a retrospective case series, 26 eyes in 26 consecutive patients diagnosed with UE after the treatment of intraocular pressure (IOP)-lowering medication for the attack of APAC were enrolled. The unaffected fellow eyes served as controls. The morphological changes were observed by ultrasonography, slit lamp microscopy and gonioscopy. UBM was used to assess the degree and extent of effusion based on the analysis of parameters associated with UE. RESULTS The mean IOP was 9.2 (SD 2.1) mm Hg at the diagnosis of UE after IOP-lowering medication, while 14.1 (SD, 2.6) mm Hg in the fellow eyes (P=0.000). The anterior chamber depth (ACD) (P=0.000), angle opening distance at 500 µm (AOD500) (P<0.01) and anterior chamber angle (ACA) (P<0.05) were decreased significantly, while ciliary body thickness (CBT) (P<0.05) increased significantly in UE eyes. UE grade analysis showed 7 eyes in grade 1, 9 eyes in grade 2, and 10 eyes in grade 3. Quadrant scores were performed of 4 eyes in 1 quadrant, 3 eyes in 3 quadrants, and 19 eyes in 4 quadrants. There was the positive correlation between grade and quadrant score (r=0.644, P=0.000). The effusion on all eyes were recovered after medication, which mean IOP was 13.9 (SD, 2.8) mm Hg. CONCLUSION UE is a frequent complication in Chinese patients after the attack of APAC, partially associated with hypotony. The severity of UE is correlation with height of effusion, extent of detachment, and shallower ACD. PMID:28393032

24 CFR 203.256 - Insurance of open-end advance.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Insurance of open-end advance. 203.256 Section 203.256 Housing and Urban Development Regulations Relating to Housing and Urban... Insurance § 203.256 Insurance of open-end advance. Insurance on an open-end advance will be evidenced by...

24 CFR 203.256 - Insurance of open-end advance.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Insurance of open-end advance. 203.256 Section 203.256 Housing and Urban Development Regulations Relating to Housing and Urban... Insurance § 203.256 Insurance of open-end advance. Insurance on an open-end advance will be evidenced by...

24 CFR 203.256 - Insurance of open-end advance.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Insurance of open-end advance. 203.256 Section 203.256 Housing and Urban Development Regulations Relating to Housing and Urban... Insurance § 203.256 Insurance of open-end advance. Insurance on an open-end advance will be evidenced by...

24 CFR 203.256 - Insurance of open-end advance.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 24 Housing and Urban Development 2 2013-04-01 2013-04-01 false Insurance of open-end advance. 203.256 Section 203.256 Housing and Urban Development Regulations Relating to Housing and Urban... Insurance § 203.256 Insurance of open-end advance. Insurance on an open-end advance will be evidenced by...

24 CFR 203.256 - Insurance of open-end advance.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Insurance of open-end advance. 203.256 Section 203.256 Housing and Urban Development Regulations Relating to Housing and Urban... Insurance § 203.256 Insurance of open-end advance. Insurance on an open-end advance will be evidenced by...

Differential Association of Metabolic Risk Factors with Open Angle Glaucoma according to Obesity in a Korean Population

PubMed Central

Kim, Hyun-Ah; Han, Kyungdo; Lee, Yun-Ah; Choi, Jin A; Park, Yong-Moon

2016-01-01

The associations of the metabolic syndrome (MetS) with intraocular pressure and primary open angle glaucoma (OAG) have been reported. This study aimed to determine whether a difference in association exists between OAG and metabolic risk factors according to obesity status among Korean adults. A total of 8,816 participants (≥40 years) in the Korea National Health and Nutrition Examination Survey were classified into obese, body mass index (BMI) ≥ 25 kg/m2 and non-obese, BMI < 25 kg/m2. The prevalence of MetS was 40.1% in non-obese OAG and 66.0% in obese OAG. The prevalence of OAG increased with increasing number components for MetS in total population and in non-obese subjects (P < 0.001, respectively), while the prevalence of OAG was not associated with number of components for MetS in obese subjects (P = 0.14). In non-obese individuals, subjects with high triglycerides, high blood pressure (BP), and MetS were more likely to have OAG compared with those without high triglycerides, high BP, and MetS after adjusting for potential confounders. However, MetS or its components exhibited no significant association with glaucoma status in obese individuals. Our study provides understanding on the differences in association of OAG with MetS and its components according to obesity status. PMID:28004731

The relationship between the fistula tract and the facial nerve in type II first branchial cleft anomalies.

PubMed

Ertas, Burak; Gunaydin, Rıza Onder; Unal, Omer Faruk

2015-04-01

To share our experience involving seven patients with type II first branchial cleft anomalies (hereafter, type II anomalies), to determine whether the location of the external fistula openings of the anomalies are associated with the location of the facial nerve tract, and elucidate the relationship between the location of the fistula opening and the facial nerve. The medical records of seven patients who underwent surgery from 2005 to 2013 for type II anomalies were retrospectively examined. The relationship between the fistula opening and the facial nerve was evaluated in each patient with respect to whether the fistula opening was superior or inferior to the mandibular angle. All patients underwent partial parotidectomy, facial nerve exposure, and total excision of the mass together with connection of a small cuff of the external auditory canal skin to the fistula tract. The fistula tracts were located medially to the facial nerve in two patients, and both fistulae had openings inferior to the mandibular angle. The fistula tracts were located laterally to the facial nerve in the remaining five patients: one patient had no external opening, one had an opening inferior to the mandibular angle, and the remaining three had openings superior to the mandibular angle. Because type II anomalies are rare, their diagnosis is difficult. Surgery of such lesions is challenging and associated with a high risk due to their proximity to the facial nerve. We believe that the location of the fistula opening may help to identify the relationship between the anomalous lesion and facial nerve. Studies involving larger series of cases are needed to confirm our hypothesis; however, because of the rarity of this specific anomaly, it will not be easy to compile a large number of cases. We believe that our study will encourage further investigation on this subject. Copyright © 2014. Published by Elsevier Ireland Ltd.

Plateau Iris - Therapeutic options and functional results after treatment.

PubMed

Feraru, Crenguța; Bâlha, Andrei; Aursulesei, Victor; Filip, Andrei; Pantalon, Anca

2017-01-01

We present the therapeutic options and functional results in patients with plateau iris (syndrome or configuration) in consecutive case series. Material and method: Our study included newly diagnosed patients with acute angle closure by "plateau iris" (configuration or syndrome), between June 2016 and April 2017. Series of 8 consecutive patients met the inclusion criteria, all being females. All the patients underwent an individualized treatment according to the underlying mechanism and evolution. Functional results (visual acuity, IOP, topical medication) were reported in the current paper. Results: For 10 months, we diagnosed 14 eyes, from 9 patients with acute angle closure by Plateau Iris, distributed as it follows: 6 eyes with closed angle glaucoma (optic disk and visual field changes), 8 eyes with plateau iris syndrome and 2 eyes with plateau iris configuration. 7/ 8 patients were misdiagnosed with primary open angle glaucoma, whereas only one patient had the correct diagnosis of closed angle glaucoma and underwent peripheral laser iridotomy. As treatment options in our study, we recommended and performed argon laser peripheral iridoplasty + iridotomy in 10/ 14 eyes, cataract lens was extracted in 4 eyes and then replaced with PC-IOL, whereas 2 eyes required a filtering anti-glaucoma surgery (trabeculectomy + PI). 2 eyes from the same patient could not be treated as intended as the patient refused the treatment. In this unique case, Pilocarpine (4%) was temporarily indicated. Conclusion: Plateau iris represents a diagnostic trap, but based on a thorough gonioscopic examination and a good patient history, the right diagnosis can be made, all along with a correct therapeutic approach.

Comparison of Dimensional Accuracy between Open-Tray and Closed-Tray Implant Impression Technique in 15° Angled Implants

PubMed Central

Balouch, F; Jalalian, E; Nikkheslat, M; Ghavamian, R; Toopchi, Sh; Jallalian, F; Jalalian, S

2013-01-01

Statement of Problem: Various impression techniques have different effects on the accuracy of final cast dimensions. Meanwhile; there are some controversies about the best technique. Purpose: This study was performed to compare two kinds of implant impression methods (open tray and closed tray) on 15 degree angled implants. Materials and Method: In this experimental study, a steel model with 8 cm in diameter and 3 cm in height were produced with 3 holes devised inside to stabilize 3 implants. The central implant was straight and the other two implants were 15° angled. The two angled implants had 5 cm distance from each other and 3.5 cm from the central implant. Dental stone, high strength (type IV) was used for the main casts. Impression trays were filled with poly ether, and then the two impression techniques (open tray and closed tray) were compared. To evaluate positions of the implants, each cast was analyzed by CMM device in 3 dimensions (x,y,z). Differences in the measurements obtained from final casts and laboratory model were analyzed using t-Test. Results: The obtained results indicated that closed tray impression technique was significantly different in dimensional accuracy when compared with open tray method. Dimensional changes were 129 ± 37μ and 143.5 ± 43.67μ in closed tray and open tray, while coefficient of variation in closed- tray and open tray were reported to be 27.2% and 30.4%, respectively. Conclusion: Closed impression technique had less dimensional changes in comparison with open tray method, so this study suggests that closed tray impression technique is more accurate. PMID:24724130

Holographic Jet Shapes and their Evolution in Strongly Coupled Plasma

NASA Astrophysics Data System (ADS)

Brewer, Jasmine; Rajagopal, Krishna; Sadofyev, Andrey; van der Schee, Wilke

2017-11-01

Recently our group analyzed how the probability distribution for the jet opening angle is modified in an ensemble of jets that has propagated through an expanding cooling droplet of plasma [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603]. Each jet in the ensemble is represented holographically by a string in the dual 4+1- dimensional gravitational theory with the distribution of initial energies and opening angles in the ensemble given by perturbative QCD. In [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603], the full string dynamics were approximated by assuming that the string moves at the speed of light. We are now able to analyze the full string dynamics for a range of possible initial conditions, giving us access to the dynamics of holographic jets just after their creation. The nullification timescale and the features of the string when it has nullified are all results of the string evolution. This emboldens us to analyze the full jet shape modification, rather than just the opening angle modification of each jet in the ensemble as in [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603]. We find the result that the jet shape scales with the opening angle at any particular energy. We construct an ensemble of dijets with energies and energy asymmetry distributions taken from events in proton-proton collisions, opening angle distribution as in [K. Rajagopal, A. V. Sadofyev, W. van der Schee, Phys. Rev. Lett. 116 (2016) 211603], and jet shape taken from proton-proton collisions and scaled according to our result. We study how these observables are modified after we send the ensemble of dijets through the strongly-coupled plasma.

Transverse tails and higher order moments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Spence, W.L.; Decker, F.J.; Woodley, M.D.

1993-05-01

The tails that may be engendered in a beam`s transverse phase space distribution by, e.g., intrabunch wakefields and nonlinear magnetic fields, are all important diagnostic and object of tuning in linear colliders. Wire scanners or phosphorescent screen monitors yield one dimensional projected spatial profiles of such beams that are generically asymmetric around their centroids, and therefore require characterization by the third moment {l_angle}x{sup 3}{r_angle} in addition to the conventional mean-square or second moment. A set of measurements spread over sufficient phase advance then allows the complete set {l_angle}x{sup 3}{r_angle}, {l_angle}xx{prime}{sup 2}{r_angle}, {l_angle}x{prime}{sup 3}{r_angle}, and {l_angle}x{sup 2}x{prime}{r_angle} to be deduced --more » the natural extension of the well-known ``emittance measurement`` treatment of second moments. The four third moments may be usefully decomposed into parts rotating in phase space at the {beta}-tron frequency and at its third harmonic, each specified by a phase-advance-invariant amplitude and a phase. They provide a framework for the analysis and tuning of transverse wakefield tails.« less

Characterization of Dilatant Shear Bands in Castlegate Sandstone Using Micro-Computed Tomography

NASA Astrophysics Data System (ADS)

Rosenthal, R. E.; Issen, K. A.; Richards, M. C.; Ingraham, M. D.

2016-12-01

Deformation bands in granular rock are thin tabular zones of localized shear and/or volumetric strain, which affect permeability and can impact fluid flow, extraction and storage. The present work characterizes dilatant shear bands formed in Castlegate sandstone (a high porosity reservoir analog) during true triaxial laboratory testing (Ingraham et al., 2013a) at low mean stresses. X-ray micro-computed tomography (micro-CT) scans produced 3-dimensional voxel files containing density information of tested specimens. Micro-CT data were thresholded to extract the least dense voxels, corresponding to pore space and localized dilation. Plane fits were determined by a custom algorithm that calculated the angle between the band normal and maximum compression direction. For tests at the same mean stress, the band angle is lower when intermediate principal stress approaches minimum compression and higher when it approaches maximum compression. Micro-CT band angles were compared to angles from the specimen jackets (Ingraham et al., 2013a), and band angles from plane fits through located acoustic emissions (AE) events (Ingraham et al. 2013b). For non-axisymmetric stress states (three unique principal stresses), one primary dilatant shear band formed in each specimen. Occasionally, secondary bands traversing part of the specimen were also identified. The principal band angles from the micro-CT scans were on average within 3 degrees of the jacket angles and within 9 degrees of AE angles. For axisymmetric stress states (intermediate principal stress equal to maximum or minimum compression) micro-CT results reveal multiple conjugate and/or parallel bands. Each jacket angle correlated to a micro-CT angle within 4 degrees. Micro-CT results also reveal that, regardless of stress state, each band is comprised of a network of interconnected pore space pathways meandering between grain clusters, as opposed to an opening fracture/joint. Ingraham MD, KA Issen, DJ Holcomb, 2013a, J. Geophys. Res. Solid Earth, Vol. 118, pp. 536-552, doi:10.1002/jgrb.50084. Ingraham MD, KA Issen, DJ Holcomb, 2013b, Acta Geotech., Vol. 8, Iss. 6, pp. 645-663, DOI: 10.1007/s11440-013-0275-y.

Using Digital Technology to See Angles from Different Angles. Part 2: Openings and Turns

ERIC Educational Resources Information Center

Host, Erin; Baynham, Emily; McMaster, Heather

2015-01-01

Ever wondered how to use technology to teach angles? This article follows on from an earlier article published last year, providing a range of ideas for integrating technology and concrete materials with the teaching of angle concepts. The authors also provide a comprehensive list of free online games and learning objects that can be used to teach…

Advanced recovery systems wind tunnel test report

NASA Technical Reports Server (NTRS)

Geiger, R. H.; Wailes, W. K.

1990-01-01

Pioneer Aerospace Corporation (PAC) conducted parafoil wind tunnel testing in the NASA-Ames 80 by 120 test sections of the National Full-Scale Aerodynamic Complex, Moffett Field, CA. The investigation was conducted to determine the aerodynamic characteristics of two scale ram air wings in support of air drop testing and full scale development of Advanced Recovery Systems for the Next Generation Space Transportation System. Two models were tested during this investigation. Both the primary test article, a 1/9 geometric scale model with wing area of 1200 square feet and secondary test article, a 1/36 geometric scale model with wing area of 300 square feet, had an aspect ratio of 3. The test results show that both models were statically stable about a model reference point at angles of attack from 2 to 10 degrees. The maximum lift-drag ratio varied between 2.9 and 2.4 for increasing wing loading.

Two Independent Mutations in ADAMTS17 Are Associated with Primary Open Angle Glaucoma in the Basset Hound and Basset Fauve de Bretagne Breeds of Dog.

PubMed

Oliver, James A C; Forman, Oliver P; Pettitt, Louise; Mellersh, Cathryn S

2015-01-01

Mutations in ADAMTS10 (CFA20) have previously been associated with primary open angle glaucoma (POAG) in the Beagle and Norwegian Elkhound. The closely related gene, ADAMTS17, has also been associated with several different ocular phenotypes in multiple breeds of dog, including primary lens luxation and POAG. We investigated ADAMTS17 as a candidate gene for POAG in the Basset Hound and Basset Fauve de Bretagne dog breeds. We performed ADAMTS17 exon resequencing in three Basset Hounds and three Basset Fauve de Bretagne dogs with POAG. Identified variants were genotyped in additional sample cohorts of both breeds and dogs of other breeds to confirm their association with disease. All affected Basset Hounds were homozygous for a 19 bp deletion in exon 2 that alters the reading frame and is predicted to lead to a truncated protein. Fifty clinically unaffected Basset Hounds were genotyped for this mutation and all were either heterozygous or homozygous for the wild type allele. Genotyping of 223 Basset Hounds recruited for a different study revealed a mutation frequency of 0.081 and predicted frequency of affected dogs in the population to be 0.007. Based on the entire genotyping dataset the association statistic for the POAG-associated deletion was p = 1.26 x 10-10. All affected Basset Fauve de Bretagne dogs were homozygous for a missense mutation in exon 11 causing a glycine to serine amino acid substitution (G519S) in the disintegrin-like domain of ADAMTS17 which is predicted to alter protein function. Unaffected Basset Fauve de Bretagne dogs were either heterozygous for the mutation (5/24) or homozygous for the wild type allele (19/24). Based on the entire genotyping dataset the association statistic for the POAG-associated deletion was p = 2.80 x 10-7. Genotyping of 85 dogs of unrelated breeds and 90 dogs of related breeds for this variant was negative. This report documents strong associations between two independent ADAMTS17 mutations and POAG in two different dog breeds.

Minimally Invasive and Open Distal Chevron Osteotomy for Mild to Moderate Hallux Valgus.

PubMed

Brogan, Kit; Lindisfarne, Edward; Akehurst, Harold; Farook, Usama; Shrier, Will; Palmer, Simon

2016-11-01

Minimally invasive surgical (MIS) techniques are increasingly being used in foot and ankle surgery but it is important that they are adopted only once they have been shown to be equivalent or superior to open techniques. We believe that the main advantages of MIS are found in the early postoperative period, but in order to adopt it as a technique longer-term studies are required. The aim of this study was to compare the 2-year outcomes of a third-generation MIS distal chevron osteotomy with a comparable traditional open distal chevron osteotomy for mild-moderate hallux valgus. Our null hypothesis was that the 2 techniques would yield equivalent clinical and radiographic results at 2 years. This was a retrospective cohort study. Eighty-one consecutive feet (49 MIS and 32 open distal chevron osteotomies) were followed up for a minimum 24 months (range 24-58). All patients were clinically assessed using the Manchester-Oxford Foot Questionnaire. Radiographic measures included hallux valgus angle, the intermetatarsal angle, hallux interphalangeal angle, metatarsal phalangeal joint angle, distal metatarsal articular angle, tibial sesamoid position, shape of the first metatarsal head, and plantar offset. Statistical analysis was done using Student t test or Wilcoxon rank-sum test for continuous data and Pearson chi-square test for categorical data. Clinical and radiologic postoperative scores in all domains were substantially improved in both groups (P < .001), but there was no statistically significant difference in improvement of any domain between open and MIS groups (P > .05). There were no significant differences in complications between the 2 groups ( > .5). The midterm results of this third-generation technique show that it was a safe procedure with good clinical outcomes and comparable to traditional open techniques for symptomatic mild-moderate hallux valgus. Level III, retrospective comparative study. © The Author(s) 2016.

CH5M3D: an HTML5 program for creating 3D molecular structures.

PubMed

Earley, Clarke W

2013-11-18

While a number of programs and web-based applications are available for the interactive display of 3-dimensional molecular structures, few of these provide the ability to edit these structures. For this reason, we have developed a library written in JavaScript to allow for the simple creation of web-based applications that should run on any browser capable of rendering HTML5 web pages. While our primary interest in developing this application was for educational use, it may also prove useful to researchers who want a light-weight application for viewing and editing small molecular structures. Molecular compounds are drawn on the HTML5 Canvas element, with the JavaScript code making use of standard techniques to allow display of three-dimensional structures on a two-dimensional canvas. Information about the structure (bond lengths, bond angles, and dihedral angles) can be obtained using a mouse or other pointing device. Both atoms and bonds can be added or deleted, and rotation about bonds is allowed. Routines are provided to read structures either from the web server or from the user's computer, and creation of galleries of structures can be accomplished with only a few lines of code. Documentation and examples are provided to demonstrate how users can access all of the molecular information for creation of web pages with more advanced features. A light-weight (≈ 75 kb) JavaScript library has been made available that allows for the simple creation of web pages containing interactive 3-dimensional molecular structures. Although this library is designed to create web pages, a web server is not required. Installation on a web server is straightforward and does not require any server-side modules or special permissions. The ch5m3d.js library has been released under the GNU GPL version 3 open-source license and is available from http://sourceforge.net/projects/ch5m3d/.

CH5M3D: an HTML5 program for creating 3D molecular structures

PubMed Central

2013-01-01

Background While a number of programs and web-based applications are available for the interactive display of 3-dimensional molecular structures, few of these provide the ability to edit these structures. For this reason, we have developed a library written in JavaScript to allow for the simple creation of web-based applications that should run on any browser capable of rendering HTML5 web pages. While our primary interest in developing this application was for educational use, it may also prove useful to researchers who want a light-weight application for viewing and editing small molecular structures. Results Molecular compounds are drawn on the HTML5 Canvas element, with the JavaScript code making use of standard techniques to allow display of three-dimensional structures on a two-dimensional canvas. Information about the structure (bond lengths, bond angles, and dihedral angles) can be obtained using a mouse or other pointing device. Both atoms and bonds can be added or deleted, and rotation about bonds is allowed. Routines are provided to read structures either from the web server or from the user’s computer, and creation of galleries of structures can be accomplished with only a few lines of code. Documentation and examples are provided to demonstrate how users can access all of the molecular information for creation of web pages with more advanced features. Conclusions A light-weight (≈ 75 kb) JavaScript library has been made available that allows for the simple creation of web pages containing interactive 3-dimensional molecular structures. Although this library is designed to create web pages, a web server is not required. Installation on a web server is straightforward and does not require any server-side modules or special permissions. The ch5m3d.js library has been released under the GNU GPL version 3 open-source license and is available from http://sourceforge.net/projects/ch5m3d/. PMID:24246004

The Effect of Phacoemulsification on Intraocular Pressure in Glaucoma Patients: A Report by the American Academy of Ophthalmology.

PubMed

Chen, Philip P; Lin, Shan C; Junk, Anna K; Radhakrishnan, Sunita; Singh, Kuldev; Chen, Teresa C

2015-07-01

To examine effects of phacoemulsification on longer-term intraocular pressure (IOP) in patients with medically treated primary open-angle glaucoma (POAG; including normal-tension glaucoma), pseudoexfoliation glaucoma (PXG), or primary angle-closure glaucoma (PACG), without prior or concurrent incisional glaucoma surgery. PubMed and Cochrane database searches, last conducted in December 2014, yielded 541 unique citations. Panel members reviewed titles and abstracts and selected 86 for further review. The panel reviewed these articles and identified 32 studies meeting the inclusion criteria, for which the panel methodologist assigned a level of evidence based on standardized grading adopted by the American Academy of Ophthalmology. One, 15, and 16 studies were rated as providing level I, II, and III evidence, respectively. All follow-up, IOP, and medication data listed are weighted means. In general, the studies reported on patients using few glaucoma medications (1.5-1.9 before surgery among the different diagnoses). For POAG, 9 studies (total, 461 patients; follow-up, 17 months) showed that phacoemulsification reduced IOP by 13% and glaucoma medications by 12%. For PXG, 5 studies (total, 132 patients; follow-up, 34 months) showed phacoemulsification reduced IOP by 20% and glaucoma medications by 35%. For chronic PACG, 12 studies (total, 495 patients; follow-up, 16 months) showed phacoemulsification reduced IOP by 30% and glaucoma medications by 58%. Patients with acute PACG (4 studies; total, 119 patients; follow-up, 24 months) had a 71% reduction from presenting IOP and rarely required long-term glaucoma medications when phacoemulsification was performed soon after medical reduction of IOP. Trabeculectomy after phacoemulsification was uncommon; the median rate reported within 6 to 24 months of follow-up in patients with controlled POAG, PXG, or PACG was 0% and was 7% in patients with uncontrolled chronic PACG. Phacoemulsification typically results in small, moderate, and marked reductions of IOP and medications for patients with POAG, PXG, and PACG, respectively, and using 1 to 2 medications before surgery. Trabeculectomy within 6 to 24 months after phacoemulsification is rare in such patients. However, reports on its effects in eyes with advanced disease or poor IOP control before surgery are few, particularly for POAG and PXG. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Gonioscopy in primary angle closure glaucoma.

PubMed

Bruno, Christina A; Alward, Wallace L M

2002-06-01

Primary angle closure is a condition characterized by obstruction to aqueous humor outflow by the peripheral iris, and results in changes in the iridocorneal angle that are visible through gonioscopic examination. Gonioscopy in these eyes, however, can be difficult. This chapter discusses techniques that might help in the examination. These include beginning the examination with the inferior angle, methods to help in looking over the iris, cycloplegia, locating the corneal wedge, indentation, van Herick estimation, examining the other eye, and topical glycerin. Finally, there is a discussion about the pathology associated with the closed angle, with emphasis on the appearance of iris bombé, plateau iris, and the distinction between iris processes and peripheral anterior synechiae.

The Prevalence of Age-Related Eye Diseases and Visual Impairment in Aging: Current Estimates

PubMed Central

Klein, Ronald; Klein, Barbara E. K.

2013-01-01

Purpose. To examine prevalence of five age-related eye conditions (age-related cataract, AMD, open-angle glaucoma, diabetic retinopathy [DR], and visual impairment) in the United States. Methods. Review of published scientific articles and unpublished research findings. Results. Cataract, AMD, open-angle glaucoma, DR, and visual impairment prevalences are high in four different studies of these conditions, especially in people over 75 years of age. There are disparities among racial/ethnic groups with higher age-specific prevalence of DR, open-angle glaucoma, and visual impairment in Hispanics and blacks compared with whites, higher prevalence of age-related cataract in whites compared with blacks, and higher prevalence of late AMD in whites compared with Hispanics and blacks. The estimates are based on old data and do not reflect recent changes in the distribution of age and race/ethnicity in the United States population. There are no epidemiologic estimates of prevalence for many visually-impairing conditions. Conclusions. Ongoing prevalence surveys designed to provide reliable estimates of visual impairment, AMD, age-related cataract, open-angle glaucoma, and DR are needed. It is important to collect objective data on these and other conditions that affect vision and quality of life in order to plan for health care needs and identify areas for further research. PMID:24335069

Resident-performed laser peripheral iridotomy in primary angle closure, primary angle closure suspects, and primary angle closure glaucoma.

PubMed

Kam, Jason P; Zepeda, Emily M; Ding, Leona; Wen, Joanne C

2017-01-01

To investigate the power use and complication frequency of resident-performed laser peripheral iridotomy (LPI). A retrospective analysis of 196 eyes from 103 patients who underwent neodymium: yttrium-aluminum-garnet laser iridotomy performed by resident physicians from January 1, 2010 through April 30, 2015 at a university-based county hospital was done. All patients were treated for primary angle closure, primary angle closure suspects, and primary angle closure glaucoma. Data were collected on pre- and post-laser intraocular pressure (IOP), ethnicity, laser parameters and complications. Mean power use and frequency of complications were evaluated. Complications included elevated post-laser IOP at 30-45 minutes (≥8 mmHg), hyphema, aborted procedures, and lasering non-iris structures. The number of repeated LPI procedures, was also recorded. Mean total power used for all residents was 78.2±68.7 mJ per eye. Power use by first-year trainees was significantly higher than second- and third-year trainees (103.5±75.5 mJ versus 73.7±73.8 mJ and 67.2±56.4 mJ, respectively, p =0.011). Complications included hyphema or microhyphema in 17.9% (35/196), IOP spikes in 5.1% (10/196), aborted procedures in 1.1% (3/196) and lasering non-iris structures in 0.5% (1/196). LPI was repeated in 22.4% of cases (44/196) with higher incidence of repeat LPI among non-Caucasian compared to the Caucasian subjects ( p =0.02). Complication rates did not differ with increased training ( p =0.16). Total power used for LPI decreased with increased resident training, while the complication rate did not differ significantly among resident classes. Complication rates were comparable to rates reported in the literature for attending-performed LPIs.

Investigation of Blade Angle of an Open Cross-Flow Runner

NASA Astrophysics Data System (ADS)

Katayama, Yusuke; Iio, Shouichiro; Veerapun, Salisa; Uchiyama, Tomomi

2015-04-01

The aim of this study was to develop a nano-hydraulic turbine utilizing drop structure in irrigation channels or industrial waterways. This study was focused on an open-type cross-flow turbine without any attached equipment for cost reduction and easy maintenance. In this study, the authors used an artificial indoor waterfall as lab model. Test runner which is a simple structure of 20 circular arc-shaped blades sandwiched by two circular plates was used The optimum inlet blade angle and the relationship between the power performance and the flow rate approaching theoretically and experimentally were investigated. As a result, the optimum inlet blade angle due to the flow rate was changed. Additionally, allocation rate of power output in 1st stage and 2nd stage is changed by the blade inlet angle.

Breakthrough in 4π ion emission mechanism understanding in plasma focus devices.

PubMed

Sohrabi, Mehdi; Zarinshad, Arefe; Habibi, Morteza

2016-12-12

Ion emission angular distribution mechanisms in plasma focus devices (PFD) have not yet been well developed and understood being due to the lack of an efficient wide-angle ion distribution image detection system to characterize a PFD space in detail. Present belief is that the acceleration of ions points from "anode top" upwards in forward direction within a small solid angle. A breakthrough is reported in this study, by mega-size position-sensitive polycarbonate ion image detection systems invented, on discovery of 4π ion emission from the "anode top" in a PFD space after plasma pinch instability and radial run-away of ions from the "anode cathodes array" during axial acceleration of plasma sheaths before the radial phase. These two ion emission source mechanisms behave respectively as a "Point Ion Source" and a "Line Ion Source" forming "Ion Cathode Shadows" on mega-size detectors. We believe that the inventions and discoveries made here will open new horizons for advanced ion emission studies towards better mechanisms understanding and in particular will promote efficient applications of PFDs in medicine, science and technology.

Pilot Study of the Effects of Ambient Light Level Variation on Spectral Domain Anterior Segment OCT-Derived Angle Metrics in Caucasians versus Asians.

PubMed

Dastiridou, Anna; Marion, Kenneth; Niemeyer, Moritz; Francis, Brian; Sadda, Srinivas; Chopra, Vikas

2018-04-11

To investigate the effects of ambient light level variation on spectral domain anterior segment optical coherence tomography (SD-ΟCT)-derived anterior chamber angle metrics in Caucasians versus Asians. Caucasian (n = 24) and Asian participants of Chinese ancestry (n = 24) with open angles on gonioscopy had one eye imaged twice at five strictly controlled, ambient light levels. Ethnicity was self-reported. Light levels were strictly controlled using a light meter at 1.0, 0.75, 0.5, 0.25, and 0 foot candle illumination levels. SD-OCT 5-line raster scans at the inferior 270° irido-corneal angle were measured by two trained, masked graders from the Doheny Image Reading Center using customized Image-J software. Schwalbe's line-angle opening distance (SL-AOD) and SL-trabecular iris space area (SL-TISA) in different light meter readings (LMRs) between the two groups were compared. Baseline light SL-AOD and SL-TISA measured 0.464 ± 0.115mm/0.351 ± 0.110mm 2 and 0.344 ± 0.118mm/0.257 ± 0.092mm 2 , respectively, in the Caucasian and the Asian group. SL-AOD and SL-TISA in each LMR were significantly larger in the Caucasian group compared to the Asian group (p < 0.05). Despite this difference in angle size between the groups, there were no statistically significant differences in the degree of change in angle parameters from light to dark (% changes in SL-AOD or SL-TISA between the two groups were statistically similar with all p-values >0.3). SL-based angle dimensions using SD-OCT are sensitive to changes in ambient illumination in participants with Caucasian and Asian ancestry. Although Caucasian eyes had larger baseline angle opening under bright light conditions, the light-to-dark change in angle dimensions was similar in the two groups.

Observation of open-orbit Fermi surface topology in the extremely large magnetoresistance semimetal MoAs2

NASA Astrophysics Data System (ADS)

Lou, R.; Xu, Y. F.; Zhao, L.-X.; Han, Z.-Q.; Guo, P.-J.; Li, M.; Wang, J.-C.; Fu, B.-B.; Liu, Z.-H.; Huang, Y.-B.; Richard, P.; Qian, T.; Liu, K.; Chen, G.-F.; Weng, H. M.; Ding, H.; Wang, S.-C.

2017-12-01

While recent advances in band theory and sample growth have expanded the series of extremely large magnetoresistance (XMR) semimetals in transition-metal dipnictides T m P n2 (T m =Ta , Nb; P n =P , As, Sb), the experimental study on their electronic structure and the origin of XMR is still absent. Here, using angle-resolved photoemission spectroscopy combined with first-principles calculations and magnetotransport measurements, we performed a comprehensive investigation on MoAs2, which is isostructural to the T m P n2 family and also exhibits quadratic XMR. We resolve a clear band structure well agreeing with the predictions. Intriguingly, the unambiguously observed Fermi surfaces (FSs) are dominated by an open-orbit topology extending along both the [100] and [001] directions in the three-dimensional Brillouin zone. We further reveal the trivial topological nature of MoAs2 by bulk parity analysis. Based on these results, we examine the proposed XMR mechanisms in other semimetals, and conclusively ascribe the origin of quadratic XMR in MoAs2 to the carriers motion on the FSs with dominant open-orbit topology, innovating in the understanding of quadratic XMR in semimetals.

Vismodegib in patients with advanced basal cell carcinoma: Primary analysis of STEVIE, an international, open-label trial.

PubMed

Basset-Séguin, N; Hauschild, A; Kunstfeld, R; Grob, J; Dréno, B; Mortier, L; Ascierto, P A; Licitra, L; Dutriaux, C; Thomas, L; Meyer, N; Guillot, B; Dummer, R; Arenberger, P; Fife, K; Raimundo, A; Dika, E; Dimier, N; Fittipaldo, A; Xynos, I; Hansson, J

2017-11-01

The SafeTy Events in VIsmodEgib study (STEVIE, ClinicalTrials.gov, NCT01367665), assessed safety and efficacy of vismodegib-a first-in-class Hedgehog pathway inhibitor demonstrating clinical benefit in advanced basal cell carcinoma (BCC)-in a patient population representative of clinical practice. Primary analysis data are presented. Patients with locally advanced or metastatic BCC received oral vismodegib 150 mg/d until progressive disease, unacceptable toxicity, or withdrawal. Primary objective was safety. Efficacy variables were assessed as secondary end-points. Evaluable adult patients (N = 1215, 1119 locally advanced; 96 metastatic BCC) from 36 countries were treated; 147 patients (12%) remained on study at time of reporting. Median (range) treatment duration was 8.6 (0-44) months. Most patients (98%) had ≥1 treatment-emergent adverse event (TEAE). The incidence of the most common TEAEs was consistent with reports in previous analyses. No association between creatine phosphokinase (CPK) abnormalities and muscle spasm was observed. Serious TEAEs occurred in 289 patients (23.8%). Exposure ≥12 months did not lead to increased incidence or severity of new TEAEs. The majority of the most common TEAEs ongoing at time of treatment discontinuation resolved by 12 months afterwards, regardless of Gorlin syndrome status. Response rates (investigator-assessed) in patients with histologically confirmed measurable baseline disease were 68.5% (95% confidence interval (CI) 65.7-71.3) in patients with locally advanced BCC and 36.9% (95% CI 26.6-48.1) in patients with metastatic BCC. The primary analysis of STEVIE demonstrates that vismodegib is tolerable in typical patients in clinical practice; safety profile is consistent with that in previous reports. Long-term exposure was not associated with worsening severity/frequency of TEAEs. Investigator-assessed response rates showed high rate of tumour control. CLINICALTRIALS.GOV: NCT01367665. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Phase-space dynamics of runaway electrons in magnetic fields

DOE PAGES

Guo, Zehua; McDevitt, Christopher Joseph; Tang, Xian-Zhu

2017-02-16

Dynamics of runaway electrons in magnetic fields are governed by the competition of three dominant physics: parallel electric field acceleration, Coulomb collision, and synchrotron radiation. Examination of the energy and pitch-angle flows reveals that the presence of local vortex structure and global circulation is crucial to the saturation of primary runaway electrons. Models for the vortex structure, which has an O-point to X-point connection, and the bump of runaway electron distribution in energy space have been developed and compared against the simulation data. Lastly, identification of these velocity-space structures opens a new venue to re-examine the conventional understanding of runawaymore » electron dynamics in magnetic fields.« less

Evaluation of wetting ability of five new saliva substitutes on heat-polymerized acrylic resin for retention of complete dentures in dry mouth patients: a comparative study

PubMed Central

Mohsin, Abdul Habeeb Bin; Reddy, Varalakshmi; Kumar, Praveen; Raj, Jeevan; Babu, Siva Santosh

2017-01-01

Introduction The aim of this study was to evaluate & compare the wetting ability of five saliva substitutes & distilled water on heat-polymerized acrylic resin. Contact angle of the saliva substitute on denture base can be taken as an indicator of wettability. Good wetting of heat-polymerized acrylic resin is critical for optimum retention of complete dentures. Methods Two hundred & forty samples of heat-polymerized acrylic resin were fabricated using conventional method. 240 samples divided into 6 groups with 40 samples in each group. Advancing & Receding contact angles were measured using Contact Angle Goniometer & DSA4 software analysis. Results Anova test was carried out to test the significance in difference of contact angle values in the six groups. The mean of advancing angle values & mean of receding angle values of all the six groups has shown statistically significant difference between the groups. The mean of angle of hysteresis values of all the six groups are statistically not significant between the groups. A multiple comparison using Bonferroni’s test was carried out to verify the significance of difference between the contact angles in a pair of groups. Statistically significant difference was seen when Aqwet (Group II) was compared to Distilled water (Group I), Wet Mouth (Group III), E-Saliva (Group IV), Biotene (Group V), and Moi-Stir (Group VI). Conclusion The contact angles of five saliva substitutes and distilled water were measured and compared. Group II (AQWET) has the lowest advancing and receding contact angle values and the highest angle of hysteresis on heat-polymerized acrylic resin. Based on contact angle values, Group II (AQWET) has the best wetting ability on heat-cured acrylic resins. The ability of saliva to wet the denture surface is one of the most important properties for complete denture retention in dry mouth cases. PMID:29187918

Beam impingement angle effects on secondary electron emission characteristics of textured pyrolytic graphite

NASA Technical Reports Server (NTRS)

Curren, A. N.; Jensen, K. A.

1984-01-01

Experimentally determined values of true secondary electron emission and relative values of reflected primary electron yield for untreated and ion-textured pyrolytic graphite over a range of primary electron energy levels and electron beam impingement angles are presented. Information required to develop high efficiency multistage depressed collectors (MDC's) for microwave amplifier traveling-wave tubes for space communication and aircraft applications is provided. To attain the highest possible MDC efficiencies, the electrode surfaces must have low secondary electron emission characteristics. Pyrolytic graphite, a chemically vapor-deposited material, is a particularly promising candidate for this application. The pyrolytic graphite surfaces studied were tested over a range of primary electron beam energies and beam impingement angles from 200 to 2000 eV and direct (0 deg) to near-grazing angles (85 deg), respectively. Surfaces both parallel to and normal to the planes of material deposition were examined. The true secondary electron emission and reflected primary electron yield characteristics of the pyrolytic graphite surfaces are compared to those of sooted control surfaces.

Attenuation of multiples in image space

NASA Astrophysics Data System (ADS)

Alvarez, Gabriel F.

In complex subsurface areas, attenuation of 3D specular and diffracted multiples in data space is difficult and inaccurate. In those areas, image space is an attractive alternative. There are several reasons: (1) migration increases the signal-to-noise ratio of the data; (2) primaries are mapped to coherent events in Subsurface Offset Domain Common Image Gathers (SODCIGs) or Angle Domain Common Image Gathers (ADCIGs); (3) image space is regular and smaller; (4) attenuating the multiples in data space leaves holes in the frequency-Wavenumber space that generate artifacts after migration. I develop a new equation for the residual moveout of specular multiples in ADCIGs and use it for the kernel of an apex-shifted Radon transform to focus and separate the primaries from specular and diffracted multiples. Because of small amplitude, phase and kinematic errors in the multiple estimate, we need adaptive matching and subtraction to estimate the primaries. I pose this problem as an iterative least-squares inversion that simultaneously matches the estimates of primaries and multiples to the data. Standard methods match only the estimate of the multiples. I demonstrate with real and synthetic data that the method produces primaries and multiples with little cross-talk. In 3D, the multiples exhibit residual moveout in SODCIGs in in-line and cross-line offsets. They map away from zero subsurface offsets when migrated with the faster velocity of the primaries. In ADCIGs the residual moveout of the primaries as a function of the aperture angle, for a given azimuth, is flat for those angles that illuminate the reflector. The multiples have residual moveout towards increasing depth for increasing aperture angles at all azimuths. As a function of azimuth, the primaries have better azimuth resolution than the multiples at larger aperture angles. I show, with a real 3D dataset, that even below salt, where illumination is poor, the multiples are well attenuated in ADCIGs with the new Radon transform in planes of azimuth-stacked ADCIGs. The angle stacks of the estimated primaries show little residual multiple energy.

Passive rejection of heat from an isotope heat source through an open door

NASA Technical Reports Server (NTRS)

Burns, R. K.

1971-01-01

The isotope heat-source design for a Brayton power system includes a door in the thermal insulation through which the heat can be passively rejected to space when the power system is not operating. The results of an analysis to predict the heat-source surface temperature and the heat-source heat-exchanger temperature during passive heat rejection as a function of insulation door opening angle are presented. They show that for a door opening angle greater than 20 deg, the temperatures are less than the steady-state temperatures during power system operation.

The Semiotic and Conceptual Genesis of Angle

ERIC Educational Resources Information Center

Tanguay, Denis; Venant, Fabienne

2016-01-01

In the present study, we try to understand how students at the end of primary school conceive of angle: Is an angle a magnitude for them or a geometric figure, and how do they manage to coordinate the two aspects in their understanding of the concepts of angle and of angle measurement? With the aim of better grasping the way "angle" is…

[Maxillary advancement osteotomy with sequelae cleft lip and palate: Dilemma between occlusion and aesthetic profile].

PubMed

Vigneron, A; Morand, B; Lafontaine, V; Lesne, V; Lesne, C; Bettega, G

2015-11-01

Maxillary hypoplasia is a common sequela of cleft lip and palate. Its surgical treatment consists in a maxillary advancement by distraction or by conventional orthognathic surgery but morphological results are unpredictable. Our goal in this study was to see if the esthetical results (on the lip and the nose) of maxillary advancement were correlated to the preservation of lateral incisor space of the cleft side. This retrospective study included 38 patients operated between 2002 and 2013. Unilateral clefts were studied independently from bilateral clefts. Profile aesthetics was evaluated independently and subjectively by two surgeons and scored on an 8-point scale. The result was classified as "good" if the score was superior or equal to 6. The score was correlated to the following parameters: amount of maxillary advancement, upper incisor axis, preservation of the missing lateral incisor space. In the "good result" group, the space of the lateral incisor was less often preserved. The nasolabial angle was more open and the upper central incisor axis more vertical. These results were more pronounced in bilateral clefts, but also found in unilateral clefts. Under reservation of the subjective evaluation and of the small number of patients, it seemed that lateral incisor space closure improved the profile of patients treated by maxillary advancement for cleft lip and palate sequelae. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

[Basic and clinical studies of pressure-independent damaging factors of open angle glaucoma].

PubMed

Araie, Makoto

2011-03-01

Pathogenesis of open-angle glaucoma involves both pressure-dependent damaging factors and pressure-independent damaging factors. The high prevalence of open-angle glaucoma with normal pressure (normal-tension glaucoma) in Japan implies that treatment of pressure-independent damaging factors in Japanese open-angle glaucoma patients is of importance. In an attempt to investigate the roles of pressure-independent damaging factors in open-angle glaucoma, we carried out basic and clinical studies and obtained the following results. 1. The rate of deterioration of visual field after trabeculectomy in normal tension glaucoma patients with post-operative intraocular pressure (IOP) of 10 mmHg was found to be -0.25 dB/year of mean deviation (MD), suggesting that contribution of pressure-independent damaging factors to the deterioration of MD in open-angle glaucoma is around -0.25 dB/year of mean deviation (MD). 2. Experiments using isolated purified cultured retinal ganglion cells (RGCs) indicated that calcium-channel blockers and some of antiglaucoma drugs showed neuroprotective effects on RGCs at concentrations of 0.01 microM or higher. 3. In mice, damage to RGCs resulted in secondary degeneration of neurons and activation of glial cells in the lateral geniculate nucleous (LGN) and superior colliculus, and these secondary changes in the central nervous system (CNS) due to RGC damage was partly ameliorated by systemic administration of memantine. 4. Mice experimental high IOP glaucoma models could be established using laser irradiation of the limbal area, and the usefulness of Tonolab in IOP measurements of mice eye was confirmed. 5. Monkey experimental high IOP glaucoma models revealed that in the glaucomatous optic nerve head vaso-constrictive reactions to an alpha-1 agonist was abolished, while vasodilative reaction to a prostaglandin FP receptor agonist was retained. 6. In monkeys with experimental high IOP glaucoma, secondary damage to neurons in the LGN and the glial reaction to it were also found, similar to the mice experiments. In living monkeys the glial reaction in the LGN could be observed by means of positron emission tomography. 7. In the LGN of monkeys with experimental high IOP glaucoma, the M-cell system was preferentially damaged in the early stage, while in the later stages both the M- and P-cell systems were damaged. 8. In a single-instituted prospective double-blinded clinical trial, oral administration of nilvadipine at 4 mg/day, a DHP calcium-channel blocker, was found to significantly retard the visual field progression in normal tension glaucoma patients over 3 years, while significantly increasing the choroidal and optic nerve blood flow by about 35%. 9. A multi-instituted prospective double-blinded clinical trial in normal tension glaucoma patients revealed that the rate of MD deterioration under monotherapy with either topical nipradilol or timolol was around -0.05 dB/year, thought to be considerably slower than -0.25 dB/year, the commonly estimated rate of MD deterioration by pressure-independent damaging factors. The current results indicate the possibility of treatment of pressure-independent damaging factors of open-angle glaucoma in Japanese open-angle glaucoma patients with oral nilvadipine and topical anti-glaucoma agents.

Prediction of Unsteady Blade Surface Pressures on an Advanced Propeller at an Angle of Attack

NASA Technical Reports Server (NTRS)

Nallasamy, M.; Groeneweg, J. F.

1989-01-01

The numerical solution of the unsteady, three-dimensional, Euler equations is considered in order to obtain the blade surface pressures of an advanced propeller at an angle of attack. The specific configuration considered is the SR7L propeller at cruise conditions with a 4.6 deg inflow angle corresponding to the plus 2 deg nacelle tilt of the Propeller Test Assessment (PTA) flight test condition. The results indicate nearly sinusoidal response of the blade loading, with angle of attack. For the first time, detailed variations of the chordwise loading as a function of azimuthal angle are presented. It is observed that the blade is lightly loaded for part of the revolution and shocks appear from hub to about 80 percent radial station for the highly loaded portion of the revolution.

Prediction of unsteady blade surface pressures on an advanced propeller at an angle of attack

NASA Technical Reports Server (NTRS)

Nallasamy, M.; Groeneweg, J. F.

1989-01-01

The paper considers the numerical solution of the unsteady, three-dimensional, Euler equations to obtain the blade surface pressures of an advanced propeller at an angle of attack. The specific configuration considered is the SR7L propeller at cruise conditions with a 4.6 deg inflow angle corresponding to the +2 deg nacelle tilt of the Propeller Test Assessment (PTA) flight test condition. The results indicate nearly sinusoidal response of the blade loading, with angle of attack. For the first time, detailed variations of the chordwise loading as a function of azimuthal angle are presented. It is observed that the blade is lightly loaded for part of the revolution and shocks appear from hub to about 80 percent radial station for the highly loaded portion of the revolution.

Changes in anterior segment morphology in response to illumination and after laser iridotomy in Asian eyes: an anterior segment OCT study

PubMed Central

See, Jovina L S; Chew, Paul T K; Smith, Scott D; Nolan, Winifred P; Chan, Yiong‐Huak; Huang, David; Zheng, Ce; Foster, Paul J; Aung, Tin; Friedman, David S

2007-01-01

Aim Using the anterior segment optical coherence tomography (AS‐OCT) to quantify changes in anterior segment morphology going from light to dark and following laser iridotomy (LI). Methods Prospective observational study. 17 consecutive subjects without peripheral anterior synechiae undergoing LI were evaluated using gonioscopy and AS‐OCT. Angle configuration including angle opening distance (AOD) at 500 microns anterior to the scleral spur, AOD500, trabecular‐iris space area up to 750 microns from the scleral spur, TISA750 and the increase in angle opening going from dark to light conditions was determined. Results Both mean AOD500 and TISA750 increased nearly threefold going from dark to light. Both also significantly increased following LI (p<0.001) as did gonioscopic grading of the angle in all quadrants (p<0.001, McNemar's test). Angles were more than twice as wide on average in the dark after LI than before LI (p<0.05). Both the mean absolute change and the mean proportionate change in AOD500 and TISA750 when going from light to dark were greater after LI than before (p<0.05). Conclusion Increased illumination as well as LI resulted in significant widening of the anterior chamber angle. AS‐OCT (which does not require a water bath and can be performed with the patient at the slit lamp) identified similar magnitude changes as those previously reported using ultrasound biomicroscopy (UBM). Furthermore, the angle appears to open more both in absolute terms and and proportionate terms in response to illumination after LI. PMID:17504852

Foreign technology summary of flight crucial flight control systems

NASA Technical Reports Server (NTRS)

Rediess, H. A.

1984-01-01

A survey of foreign technology in flight crucial flight controls is being conducted to provide a data base for planning future research and technology programs. Only Free World countries were surveyed, and the primary emphasis was on Western Europe because that is where the most advanced technology resides. The survey includes major contemporary systems on operational aircraft, R&D flight programs, advanced aircraft developments, and major research and technology programs. The information was collected from open literature, personal communications, and a tour of several companies, government organizations, and research laboratories in the United Kingdom, France, and the Federal Republic of Germany. A summary of the survey results to date is presented.

Hi, Hokusai!

NASA Image and Video Library

2017-12-08

This dramatic image features Hokusai in the foreground, famous for its extensive set of rays, some of which extend for over a thousand kilometers across Mercury's surface. The extensive, bright rays indicate that Hokusai is one of the youngest large craters on Mercury. Check out previously featured images to see high-resolution details of its central peaks, rim and ejecta blanket, and impact melt on its floor. This image was acquired as part of MDIS's high-incidence-angle base map. The high-incidence-angle base map complements the surface morphology base map of MESSENGER's primary mission that was acquired under generally more moderate incidence angles. High incidence angles, achieved when the Sun is near the horizon, result in long shadows that accentuate the small-scale topography of geologic features. The high-incidence-angle base map was acquired with an average resolution of 200 meters/pixel. The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. During the first two years of orbital operations, MESSENGER acquired over 150,000 images and extensive other data sets. MESSENGER is capable of continuing orbital operations until early 2015. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Physicochemically Tunable Polyfunctionalized RNA Square Architecture with Fluorogenic and Ribozymatic Properties

PubMed Central

2015-01-01

Recent advances in RNA nanotechnology allow the rational design of various nanoarchitectures. Previous methods utilized conserved angles from natural RNA motifs to form geometries with specific sizes. However, the feasibility of producing RNA architecture with variable sizes using native motifs featuring fixed sizes and angles is limited. It would be advantageous to display RNA nanoparticles of diverse shape and size derived from a given primary sequence. Here, we report an approach to construct RNA nanoparticles with tunable size and stability. Multifunctional RNA squares with a 90° angle were constructed by tuning the 60° angle of the three-way junction (3WJ) motif from the packaging RNA (pRNA) of the bacteriophage phi29 DNA packaging motor. The physicochemical properties and size of the RNA square were also easily tuned by modulating the “core” strand and adjusting the length of the sides of the square via predictable design. Squares of 5, 10, and 20 nm were constructed, each showing diverse thermodynamic and chemical stabilities. Four “arms” extending from the corners of the square were used to incorporate siRNA, ribozyme, and fluorogenic RNA motifs. Unique intramolecular contact using the pre-existing intricacy of the 3WJ avoids relatively weaker intermolecular interactions via kissing loops or sticky ends. Utilizing the 3WJ motif, we have employed a modular design technique to construct variable-size RNA squares with controllable properties and functionalities for diverse and versatile applications with engineering, pharmaceutical, and medical potential. This technique for simple design to finely tune physicochemical properties adds a new angle to RNA nanotechnology. PMID:24971772

Effect of phase advance on the brushless dc motor torque speed respond

NASA Astrophysics Data System (ADS)

Mohd, M. S.; Karsiti, M. N.; Mohd, M. S.

2015-12-01

Brushless direct current (BLDC) motor is widely used in small and medium sized electric vehicles as it exhibit highest specific power and thermal efficiency as compared to the induction motor. Permanent magnets BLDC rotor create a constant magnetic flux, which limit the motor top speed. As the back electromotive force (EMF) voltage increases proportionally with motor rotational speed and it approaches the amplitude of the input voltage, the phase current amplitude will reach zero. By advancing the phase current, it is possible to extend the maximum speed of the BLDC motor beyond the rated top speed. This will allow smaller BLDC motor to be used in small electric vehicles (EV) and in larger applications will allow the use of BLDC motor without the use of multispeed transmission unit for high speed operation. However, increasing the speed of BLDC will affect the torque speed response. The torque output will decrease as speed increases. Adjusting the phase angle will affect the speed of the motor as each coil is energized earlier than the corresponding rise in the back emf of the coil. This paper discusses the phase advance strategy of Brushless DC motor by phase angle manipulation approaches using external hall sensors. Tests have been performed at different phase advance angles in advance and retard positions for different voltage levels applied. The objective is to create the external hall sensor system to commutate the BLDC motor, to establish the phase advance of the BLDC by varying the phase angle through external hall sensor manipulation, observe the respond of the motor while applying the phase advance by hall sensor adjustment.

Multicenter clinical trial of high-intensity focused ultrasound treatment in glaucoma patients without previous filtering surgery.

PubMed

Aptel, Florent; Denis, Philippe; Rouland, Jean-François; Renard, Jean-Paul; Bron, Alain

2016-08-01

To evaluate the efficacy and safety of the ultrasonic circular cyclocoagulation procedure in patients with open-angle glaucoma naïve of previous filtering surgery. Prospective non-comparative interventional clinical study conducted in five French University Hospitals. Thirty eyes of 30 patients with open-angle glaucoma, intra-ocular pressure (IOP) > 21 mmHg and with no previous filtering glaucoma surgeries were sonicated with a probe comprising six piezoelectric transducers. The six transducers were activated with a 6-s exposure time. Complete ophthalmic examinations were performed before the procedure and at 1 day, 1 week, 1, 2, 3, 6 and 12 months after the procedure. Primary outcomes were qualified surgical success (defined as IOP reduction from baseline ≥20% and IOP > 5 mmHg with possible re-intervention and without hypotensive medication adjunction) and complete surgical success (defined as IOP reduction from baseline ≥20%, IOP > 5 mmHg and IOP < 21 mmHg with possible re-intervention and without hypotensive medication adjunction) at the last follow-up visit and vision-threatening complications. Secondary outcomes were mean IOP at each follow-up visit compared with baseline, medication use, complications and re-interventions. Intra-ocular pressure was significantly reduced (p < 0.05) from a mean pre-operative value of 28.2 ± 7.2 mmHg (n = 3.6 hypotensive medications) to 19.6 ± 7.9 mmHg at 12 months (n = 3.1 hypotensive medications and n = 1.1 procedures) (mean IOP reduction of 30%). Qualified success was achieved in 63% of eyes (19/30) (mean IOP reduction of 37% in these eyes) and complete success in 46.7% of eyes (14/30) (mean IOP reduction of 37% in these eyes) at the last follow-up. No major intra- or post-operative complications occurred. The UC(3) procedure seems to be an effective and well-tolerated method to reduce IOP in patients with open-angle glaucoma without previous filtering surgery. © 2015 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

OpenSim Model Improvements to Support High Joint Angle Resistive Exercising

NASA Technical Reports Server (NTRS)

Gallo, Christopher; Thompson, William; Lewandowski, Beth; Humphreys, Brad

2016-01-01

Long duration space travel to Mars or to an asteroid will expose astronauts to extended periods of reduced gravity. Since gravity is not present to aid loading, astronauts will use resistive and aerobic exercise regimes for the duration of the space flight to minimize the loss of bone density, muscle mass and aerobic capacity that occurs during exposure to a reduced gravity environment. Unlike the International Space Station (ISS), the area available for an exercise device in the next generation of spacecraft is limited. Therefore, compact resistance exercise device prototypes are being developed. The Advanced Resistive Exercise Device (ARED) currently on the ISS is being used as a benchmark for the functional performance of these new devices. Rigorous testing of these proposed devices in space flight is difficult so computational modeling provides an estimation of the muscle forces and joint loads during exercise to gain insight on the efficacy to protect the musculoskeletal health of astronauts. The NASA Digital Astronaut Project (DAP) is supporting the Advanced Exercise Concepts (AEC) Project, Exercise Physiology and Countermeasures (ExPC) project and the National Space Biomedical Research Institute (NSBRI) funded researchers by developing computational models of exercising with these new advanced exercise device concepts

Contact angle hysteresis on superhydrophobic stripes.

PubMed

Dubov, Alexander L; Mourran, Ahmed; Möller, Martin; Vinogradova, Olga I

2014-08-21

We study experimentally and discuss quantitatively the contact angle hysteresis on striped superhydrophobic surfaces as a function of a solid fraction, ϕS. It is shown that the receding regime is determined by a longitudinal sliding motion of the deformed contact line. Despite an anisotropy of the texture the receding contact angle remains isotropic, i.e., is practically the same in the longitudinal and transverse directions. The cosine of the receding angle grows nonlinearly with ϕS. To interpret this we develop a theoretical model, which shows that the value of the receding angle depends both on weak defects at smooth solid areas and on the strong defects due to the elastic energy of the deformed contact line, which scales as ϕS(2)lnϕS. The advancing contact angle was found to be anisotropic, except in a dilute regime, and its value is shown to be determined by the rolling motion of the drop. The cosine of the longitudinal advancing angle depends linearly on ϕS, but a satisfactory fit to the data can only be provided if we generalize the Cassie equation to account for weak defects. The cosine of the transverse advancing angle is much smaller and is maximized at ϕS ≃ 0.5. An explanation of its value can be obtained if we invoke an additional energy due to strong defects in this direction, which is shown to be caused by the adhesion of the drop on solid sectors and is proportional to ϕS(2). Finally, the contact angle hysteresis is found to be quite large and generally anisotropic, but it becomes isotropic when ϕS ≤ 0.2.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, B; Wong, R; Lam, W

Purpose: To develop a practical method for routine QA of the MLC of a Tomotherapy unit using ArcCheck. Methods: Two standard test plans were used in this study. One was a helical test, in which the central leaves No. 32 and 33 opened simultaneously for 277.8ms at projections centered at 0°, 120° and 240° gantry angles. The other test plan was a static test with the gantry angle set at 0°, 45°, 90° and 135° respectively and leaves No. 32 and 33 opened sequentially for total 20s which was further divided into eleven or ten segments at each beam angle.more » The ArcCheck was isocentrically set up and adjusted for couch sag. Movie files which took a snapshot exposure every 50ms were recorded. The start/stop time of leaf open was decided by the ramp-up/ramp-down of the detectors. Results: The percentage differences between measured and planned leaf open time were calculated to be within 0.5% in all the tests. In static test, if leaves are synchronized perfectly, the sum of the two detectors’ signals after normalization should equal one when the leaves are in transition. Our results showed mean values of 0.982, 0.983, 0.978 and 0.995 at static gantry angle 0°, 45°, 90° and 135° respectively. Conclusion: A method for estimating the Tomotherapy binary MLC leaf open time using ArcCheck is proposed and proved to be precise enough to verify the planned leaf open time as small as 277.8ms. This method also makes the observation and quantification of the synchronization of leaves possible.« less

[Packaging: the guarantee of medicinal quality].

PubMed

Chaumeil, J-C

2003-01-01

Primary packaging guarantees the pharmaceutical quality of the medicinal preparation received by the patient. Glass bottles containing parenteral solutions for example ensure that sterility, quality and optimal stability are preserved until administration. Recent innovations in materials research has lead to improvements in parenteral infusions. Multicompartmental bags, allowing extemporaneous mixtures without opening the container, constitute an extremely beneficial advance for the patient, allowing administration of mixtures with solutions and emulsions which would be unstable if stored. Metered dose pressurized inhalers are an excellent example of drug administration devices designed specifically to ensure quality and bioavailability. These examples illustrate the important role of primary packaging and demonstrate the usefulness of research and development in this area.

Aeroservoelastic Wind-Tunnel Test of the SUGAR Truss Braced Wing Wind-Tunnel Model

NASA Technical Reports Server (NTRS)

Scott, Robert C.; Allen, Timothy J.; Funk, Christie J.; Castelluccio, Mark A.; Sexton, Bradley W.; Claggett, Scott; Dykman, John; Coulson, David A.; Bartels, Robert E.

2015-01-01

The Subsonic Ultra Green Aircraft Research (SUGAR) Truss-Braced Wing (TBW) aeroservoelastic (ASE) wind-tunnel test was conducted in the NASA Langley Transonic Dynamics Tunnel (TDT) and was completed in April, 2014. The primary goals of the test were to identify the open-loop flutter boundary and then demonstrate flutter suppression. A secondary goal was to demonstrate gust load alleviation (GLA). Open-loop flutter and limit cycle oscillation onset boundaries were identified for a range of Mach numbers and various angles of attack. Two sets of control laws were designed for the model and both sets of control laws were successful in suppressing flutter. Control laws optimized for GLA were not designed; however, the flutter suppression control laws were assessed using the TDT Airstream Oscillation System. This paper describes the experimental apparatus, procedures, and results of the TBW wind-tunnel test. Acquired system ID data used to generate ASE models is also discussed.2 study.

2D CFD Airfoil Analysis

NASA Astrophysics Data System (ADS)

Babb, Grace

2017-11-01

This work aims to produce a higher fidelity model of the blades for NASA's X-57 all electric propeller driven experimental aircraft. This model will, in turn, allow for more accurate calculations of the thrust each propeller can generate. This work uses computational fluid dynamics (CFD) to first analyze the propeller blades as a series of 11 differently shaped airfoils and calculate, among other things, the coefficients for lift and drag associated with each airfoil at different angles of attack. OpenFOAM-a C + + library that can be used to create series of applications for pre-processing, solving, and post-processing-is one of the primary tools utilized in these calculations. By comparing the data OpenFOAM generates about the NACA 23012 airfoil with existing experimental data about the NACA 23012 airfoil, the reliability of our model is measured and verified. A trustworthy model can then be used to generate more data and sent to NASA to aid in the design of the actual aircraft.

Pulsar gamma rays from polar cap regions

NASA Technical Reports Server (NTRS)

Chiang, James; Romani, Roger W.

1992-01-01

The production is studied of pulsar gamma rays by energetic electrons flowing in the open field region above pulsar polar caps. The propagation was followed of curvature radiation from primary electrons, as well as hard synchrotron radiation generated by secondary pairs, through the pulsar magnetosphere for vacuum dipole open field geometries. Using data from radio and optical observations, models were constructed for the specific geometries and viewing angles appropriate to particular pulsars. These detailed models produce normalized spectra above 10 MeV, pulse profiles, beaming fractions and phase resolved spectra appropriate for direct comparison with COS-B and GRO data. Models are given for the Crab, Vela, and other potentially detectable pulsars; general agreement with existing data is good, although perturbations to the simplified models are needed for close matches. The calculations were extended to the millisecond pulsar range, which allows the production of predictions for the flux and spectra of populations of recycled pulsars and search strategies are pointed out.

Experimental assessment of theory for refraction of sound by a shear layer

NASA Technical Reports Server (NTRS)

Schlinker, R. H.; Amiet, R. K.

1978-01-01

The refraction angle and amplitude changes associated with sound transmission through a circular, open-jet shear layer were studied in a 0.91 m diameter open jet acoustic research tunnel. Free stream Mach number was varied from 0.1 to 0.4. Good agreement between refraction angle correction theory and experiment was obtained over the test Mach number, frequency and angle measurement range for all on-axis acoustic source locations. For off-axis source positions, good agreement was obtained at a source-to-shear layer separation distance greater than the jet radius. Measureable differences between theory and experiment occurred at a source-to-shear layer separation distance less than one jet radius. A shear layer turbulence scattering experiment was conducted at 90 deg to the open jet axis for the same free stream Mach numbers and axial source locations used in the refraction study. Significant discrete tone spectrum broadening and tone amplitude changes were observed at open jet Mach numbers above 0.2 and at acoustic source frequencies greater than 5 kHz. More severe turbulence scattering was observed for downstream source locations.

Zero-stress states of human pulmonary arteries and veins.

PubMed

Huang, W; Yen, R T

1998-09-01

The zero-stress states of the pulmonary arteries and veins from order 3 to order 9 were determined in six normal human lungs within 15 h postmortem. The zero-stress state of each vessel was obtained by cutting the vessel transversely into a series of short rings, then cutting each ring radially, which caused the ring to spring open into a sector. Each sector was characterized by its opening angle. The mean opening angle varied between 92 and 163 degrees in the arterial tree and between 89 and 128 degrees in the venous tree. There was a tendency for opening angles to increase as the sizes of the arteries and veins increased. We computed the residual strains based on the experimental measurements and estimated the residual stresses according to Hooke's law. We found that the inner wall of a vessel at the state in which the internal pressure, external pressure, and longitudinal stress are all zero was under compression and the outer wall was in tension, and that the magnitude of compressive stress was greater than the magnitude of tensile stress.

Proposal for extension of ORSA to include phasing in to prove successive encounters of an asteroid between Earth and Mars

NASA Astrophysics Data System (ADS)

Jolitz, Benjamin

Ben Jolitz 2/6/10 Proposal for extension of ORSA to include phasing in to prove successive encounters of an asteroid between Earth and Mars Phasing is the act of changing the phase angle between two sinusoidal functions. In the case of orbits, which are ellipses drawn by sinusoidal functions, phasing is the act of matching one orbit to another. Finding the phasing parameters of a captured asteroid, a non-Keplarian object, in a resonant bi-elliptic orbit and simulation thereof is rather difficult without specialized and esoteric applications. However, open source in the last ten years has made incredible advance-ments, and some projects originally designed for orbital reconstruction have been released to the public on an AS IS basis; one such project is ORSA -Orbital Reconstruction, Simulation, Analysis. ORSA, however, does not have methods for evaluating the relative changes to a phase angle of a bi-elliptic orbit in a recursive manner for successive encounters. For years, space shuttles and other celestial transport vessels have been faced with the difficulty of docking with the International Space Station, a task which involves matching the craft to the unique elliptical orbit of the ISS such that the shuttle will meet the ISS with the appropriate orbital parameters. However, calculation of such requires consideration of only the Earth and it's effect on rather small, man-made objects. In electrical engineering, the concept of a phase lock loop is used to match the frequency and phase of a controlled oscillator with a given set of input signals. In our test case, we wish compute the successive bi-elliptic half orbits of a captured asteroid that traverses between Earth and Mars using gravitational interactions with the intent of computing the relative phase angle between the desired half orbit and current orbit such that a timed encounter with Earth or Mars is possible. The goal of this proposal is to extend ORSA to maintain relative phase angle between bi-elliptic orbits for successive encounters.

Hysteresis of the Contact Angle of a Meniscus Inside a Capillary with Smooth, Homogeneous Solid Walls.

PubMed

Kuchin, Igor V; Starov, Victor M

2016-05-31

A theory of contact angle hysteresis of a meniscus inside thin capillaries with smooth, homogeneous solid walls is developed in terms of surface forces (disjoining/conjoining pressure isotherm) using a quasi-equilibrium approach. The disjoining/conjoining pressure isotherm includes electrostatic, intermolecular, and structural components. The values of the static receding θr, advancing θa, and equilibrium θe contact angles in thin capillaries were calculated on the basis of the shape of the disjoining/conjoining pressure isotherm. It was shown that both advancing and receding contact angles depend on the capillary radius. The suggested mechanism of the contact angle hysteresis has a direct experimental confirmation: the process of receding is accompanied by the formation of thick β-films on the capillary walls. The effect of the transition from partial to complete wetting in thin capillaries is predicted and analyzed. This effect takes place in very thin capillaries, when the receding contact angle decreases to zero.

Does hemipelvis structure and position influence acetabulum orientation?

PubMed

Musielak, Bartosz; Jóźwiak, Marek; Rychlik, Michał; Chen, Brian Po-Jung; Idzior, Maciej; Grzegorzewski, Andrzej

2016-03-16

Although acetabulum orientation is well established anatomically and radiographically, its relation to the innominate bone has rarely been addressed. If explored, it could open the discussion on patomechanisms of such complex disorders as femoroacetabular impingement (FAI). We therefore evaluated the influence of pelvic bone position and structure on acetabular spatial orientation. We describe this relation and its clinical implications. This retrospective study was based on computed tomography scanning of three-dimensional models of 31 consecutive male pelvises (62 acetabulums). All measurements were based on CT spatial reconstruction with the use of highly specialized software (Rhinoceros). Relations between acetabular orientation (inclination, tilt, anteversion angles) and pelvic structure were evaluated. The following parameters were evaluated to assess the pelvic structure: iliac opening angle, iliac tilt angle, interspinous distance (ISD), intertuberous distance (ITD), height of the pelvis (HP), and the ISD/ITD/HP ratio. The linear and nonlinear dependence of the acetabular angles and hemipelvic measurements were examined with Pearson's product - moment correlation and Spearman's rank correlation coefficient. Correlations different from 0 with p < 0.05 were considered statistically significant. Comparison of the axis position with pelvis structure with orientation in the horizontal plane revealed a significant positive correlation between the acetabular anteversion angle and the iliac opening angle (p = 0.041 and 0.008, respectively). In the frontal plane, there was a positive correlation between the acetabular inclination angle and the iliac tilt angle (p = 0.025 and 0.014, respectively) and the acetabular inclination angle and the ISD/ITD/HP ratio (both p = 0.048). There is a significant correlation of the hemipelvic structure and acetabular orientation under anatomic conditions, especially in the frontal and horizontal planes. In the anteroposterior view, the more tilted-down innominate bone causes a more caudally oriented acetabulum axis, whereas in the horizontal view this relation is reversed. This study may serve as a basis for the discussion on the role of the pelvis in common disorders of the hip.

[Penetrant injuries of colon--our experience].

PubMed

Lazović, R; Krivokapić, Z; Dobricanin, V

2010-01-01

In attemption to determine the place of primary repair in management of colon injuries, an open, non randomized clinical study was performed. Retrospective (RS) group of 62 patients according to exclusion criteria by Stone (S/F) and Flint (F1) was managed by one or two stage surgical procedure. Prospective (PR) group of 34 patients was managed using one stage repair non-selectively: two stage procedures were performed in 3 cases of advanced peritonitis and multi-segmental lacerations with impaired circulation of colon. In RS group 36 patients were managed by primary repair and in PR group, 31 were managed by primary repair. Both groups were of similar age/sex. Indexes of trauma severity were similar (TS, ISS, PATI). The latent time was shorter in PR group. Associated injuries to other body regions and abdominal organs were similar in both groups. S/F criteria and Flint grading in both (RS vs. PR) groups were similar. Comparison of attempted and successful primary repairs justifies the more liberal use of primary repair in early management of colon injuries.

High contact angle hysteresis of superhydrophobic surfaces: Hydrophobic defects

NASA Astrophysics Data System (ADS)

Chang, Feng-Ming; Hong, Siang-Jie; Sheng, Yu-Jane; Tsao, Heng-Kwong

2009-08-01

A typical superhydrophobic surface is essentially nonadhesive and exhibits very low water contact angle (CA) hysteresis, so-called Lotus effect. However, leaves of some plants such as scallion and garlic with an advancing angle exceeding 150° show very serious CA hysteresis. Although surface roughness and epicuticular wax can explain the very high advancing CA, our analysis indicates that the unusual hydrophobic defect, diallyl disulfide, is the key element responsible for contact line pinning on allium leaves. After smearing diallyl disulfide on an extended polytetrafluoroethylene (PTFE) film, which is originally absent of CA hysteresis, the surface remains superhydrophobic but becomes highly adhesive.

Prevalence of glaucoma in an urban West African population: the Tema Eye Survey.

PubMed

Budenz, Donald L; Barton, Keith; Whiteside-de Vos, Julia; Schiffman, Joyce; Bandi, Jagadeesh; Nolan, Winifred; Herndon, Leon; Kim, Hanna; Hay-Smith, Graham; Tielsch, James M

2013-05-01

Multiple studies have found an increased prevalence, younger age at onset, and more severe course of glaucoma in people of African descent, but these findings are based on studies conducted outside Africa. To determine the prevalence of glaucoma in an urban West African population of adults. A population-based, cross-sectional study of adults 40 years and older conducted from September 1, 2006, through December 31, 2008, from 5 communities in Tema, Ghana. Participants from randomly selected clusters underwent a screening examination that consisted of visual acuity, frequency doubling perimetry, applanation tonometry, and optic disc photography. Participants who failed any of these tests were referred for complete examination, including gonioscopy, standard automated perimetry, and stereoscopic optic disc photography. A total of 6806 eligible participants were identified, and 5603 (82.3%) were enrolled in the study. The field examination referred 1869 participants (33.3%) to the clinic examination, and 1538 (82.2%) came for complete examination. A total of 362 participants were identified as having glaucoma of any type and category. Primary open-angle glaucoma was the underlying diagnosis in 342 participants (94.5%). The prevalence of primary open-angle glaucoma was 6.8% overall, increasing from 3.7% among those 40 to 49 years old to 14.6% among those 80 years and older, and was higher in men than in women in all age groups, with an overall male-female prevalence ratio of 1.5. Of the participants with glaucoma, 9 (2.5%) were blind using World Health Organization criteria, and only 12 (3.3%) were aware that they had glaucoma. The prevalence of glaucoma is higher in this urban West African population than in previous studies of people of East or South African and of non-African descent. Strategies to identify affected persons and effectively manage the burden of glaucoma are needed in West Africa.

Role of the water-drinking test in medically treated primary open angle glaucoma patients.

PubMed

Salcedo, H; Arciniega, D; Mayorga, M; Wu, L

2018-05-01

The water-drinking test (WDT) has recently re-emerged as a possible way to determine the competency of the trabecular meshwork. We performed a prospective interventional study to test the hypothesis that the WDT could be useful in assessing fluctuations in patients undergoing treatment for primary open angle glaucoma (POAG). We included 122 patients; 62 on medical treatment for POAG (n=123 eyes) and 60 controls (n=120 eyes). The study group had been on intraocular pressures (IOP) lowering treatment continuously for at least 3months with stable IOP. The WDT was performed during fasting and was considered positive if it fluctuated ≥6mmHg. The patients on medical treatment had a mean age of 50.56±18.45 years vs. 51.35±11.22 for the controls (P=0.34); with 71% being female in the study group and 77% in the control group. In the study group; 52% were on beta blockers (n=64), 27% combination of two or more medications (n=33), 19% prostaglandin analogues (n=24) and 2% alpha agonists (n=2). The WDT was positive in 17.07% (n=21) in the study group and 2.5% (n=3) in the control group (P=0.0001). The mean fluctuation was 7.14±2.15mmHg in the study group and 6.00±0mmHg in the controls (P=0.33). A positive WDT was found in 33.33% (n=11) of those on combination therapy; 12.5% (n=3) prostaglandin analogues and 10.94% (n=7) beta blockers (P=0.03). Combination therapy had the highest positive WDT fluctuation (7.54±2.87) followed by prostaglandin analogues (7.00±1.00) and beta blockers (6.57±0.78) with a P value of 0.44. The WDT can identify significant fluctuations in eyes with POAG that are medically treated. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Brain-Derived Neurotrophic Factor in Patients with Primary Open-Angle Glaucoma and Age-related Cataract.

PubMed

Shpak, Alexander A; Guekht, Alla B; Druzhkova, Tatiana A; Kozlova, Ksenia I; Gulyaeva, Natalia V

2018-02-01

To study brain-derived neurotrophic factor (BDNF) content in aqueous humor (AH), lacrimal fluid (LF), and blood serum (BS) in patients with age-related cataract and primary open-angle glaucoma (POAG). BDNF was studied in 57 patients with age-related cataract, 55 patients with POAG combined with cataract, and 29 healthy controls (one eye in each person). AH was sampled during cataract surgery. The levels of BDNF in LF and BS did not differ in cataract patients and controls. The concentration of BDNF (pg/mL) in patients with POAG and cataract was lower than in cataract patients in AH (35.2 ± 14.2 vs. 54.6 ± 29.6, P < 0.001), LF (78.0 ± 25.1 vs. 116.2 ± 43.1, P < 0.001), and BS (19230 ± 5960 vs. 22440 ± 7580, P < 0.02), while the AH/LF ratio was similar (0.46 ± 0.18 vs. 0.48 ± 0.19). The AH level of BDNF declined in early POAG and relatively increased in the next stages of the disease, inversely correlating with visual field index (Pearson's correlation coefficient r = -0.404, P = 0.002) and average retinal nerve fiber layer thickness (r = -0.322, P = 0.018). BDNF contents in LF and BS were also the lowest in early POAG. BDNF in AH strongly correlated with its content in LF (r = 0.66, P < 0.000). A formula was suggested to calculate the AH concentration of BDNF basing on its content in LF. BDNF contents are decreased in AH, LF, and BS of patients with POAG demonstrating a significant decrease in the early POAG and relative increase in the next stages of the disease. A strong correlation exists between BDNF contents in AH and LF.

Genetic Variants Associated with Optic Nerve Vertical Cup-to-Disc Ratio Are Risk Factors for Primary Open Angle Glaucoma in a US Caucasian Population

PubMed Central

Fan, Bao Jian; Wang, Dan Yi; Pasquale, Louis R.; Haines, Jonathan L.

2011-01-01

Purpose. Genetically complex disorders, such as primary open angle glaucoma (POAG), may include highly heritable quantitative traits as part of the overall phenotype, and mapping genes influencing the related quantitative traits may effectively identify genetic risk factors predisposing to the complex disease. Recent studies have identified SNPs associated with optic nerve area and vertical cup-to-disc ratio (VCDR). The purpose of this study was to evaluate the association between these SNPs and POAG in a US Caucasian case-control sample. Methods. Five SNPs previously associated with optic disc area, or VCDR, were genotyped in 539 POAG cases and 336 controls. Genotype data were analyzed for single SNP associations and SNP interactions with VCDR and POAG. Results. SNPs associated with VCDR rs1063192 (CDKN2B) and rs10483727 (SIX1/SIX6) were also associated with POAG (P = 0.0006 and P = 0.0043 for rs1063192 and rs10483727, respectively). rs1063192, associated with smaller VCDR, had a protective effect (odds ratio [OR] = 0.73; 95% confidence interval [CI], 0.58–0.90), whereas rs10483727, associated with larger VCDR, increased POAG risk (OR = 1.33; 95% CI, 1.08–1.65). POAG risk associated with increased VCDR was significantly influenced by the C allele of rs1900004 (ATOH7), associated with increased optic nerve area (P-interaction = 0.025; OR = 1.89; 95% CI, 1.22–2.94). Conclusions. Genetic variants influencing VCDR are associated with POAG in a US Caucasian population. Variants associated with optic nerve area are not independently associated with disease but can influence the effects of VCDR variants suggesting that increased optic disc area can significantly contribute to POAG risk when coupled with risk factors controlling VCDR. PMID:21398277

Linkage analysis of primary open-angle glaucoma excludes the juvenile glaucoma region on chromosome 1q

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wirtz, M.K.; Acott, T.S.; Samples, J.R.

1994-09-01

The gene for one form of juvenile glaucoma has been mapped to chromosome 1q21-q31. This raises the possibility of primary open-angle glaucoma (POAG) also mapping to this region if the same defective gene causes both diseases. To ask this question linkage analysis was performed on a large POAG kindred. Blood samples or skin biopsies were obtained from 40 members of this family. Individuals were diagnosed as having POAG if they met two or more of the following criteria: (1) Visual field defects compatible with glaucoma on automated perimetry; (2) Optic nerve head and/or nerve fiber layer analysis compatible with glaucomatousmore » damage; (3) high intraocular pressures (> 20 mm Hg). Patients were considered glaucoma suspects if they only met one criterion. These individuals were excluded from the analysis. Of the 40 members, seven were diagnosed with POAG; four were termed suspects. The earliest age of onset was 38 years old, while the average age of onset was 65 years old. We performed two-point and multipoint linkage analysis, using five markers which encompass the region 1q21-q31; specifically, D1S194, D1S210, D1S212, D1S191 and LAMB2. Two-point lod scores excluded tight linkage with all markers except D1S212 (maximum lod score of 1.07 at theta = 0.0). In the multipoint analysis, including D1S210-D1S212-LAMB2 and POAG, the entire 11 cM region spanned by these markers was excluded for linkage with POAG; that is, lod scores were < -2.0. In conclusion, POAG in this family does not map to chromosome 1q21-q31 and, thus, they carry a gene that is distinct from the juvenile glaucoma gene.« less

Age at natural menopause genetic risk score in relation to age at natural menopause and primary open-angle glaucoma in a US-based sample

PubMed Central

Pasquale, Louis R.; Aschard, Hugues; Kang, Jae H.; Bailey, Jessica N. Cooke; Lindström, Sara; Chasman, Daniel I.; Christen, William G.; Allingham, R. Rand; Ashley-Koch, Allison; Lee, Richard K.; Moroi, Sayoko E.; Brilliant, Murray H.; Wollstein, Gadi; Schuman, Joel S.; Fingert, John; Budenz, Donald L.; Realini, Tony; Gaasterland, Terry; Gaasterland, Douglas; Scott, William K.; Singh, Kuldev; Sit, Arthur J.; Igo, Robert P.; Song, Yeunjoo E.; Hark, Lisa; Ritch, Robert; Rhee, Douglas J.; Gulati, Vikas; Havens, Shane; Vollrath, Douglas; Zack, Donald J.; Medeiros, Felipe; Weinreb, Robert N.; Pericak-Vance, Margaret A.; Liu, Yutao; Kraft, Peter; Richards, Julia E.; Rosner, Bernard A.; Hauser, Michael A.; Haines, Jonathan L.; Wiggs, Janey L.

2017-01-01

Abstract Objective: Several attributes of female reproductive history, including age at natural menopause (ANM), have been related to primary open-angle glaucoma (POAG). We assembled 18 previously reported common genetic variants that predict ANM to determine their association with ANM or POAG. Methods: Using data from the Nurses’ Health Study (7,143 women), we validated the ANM weighted genetic risk score in relation to self-reported ANM. Subsequently, to assess the relation with POAG, we used data from 2,160 female POAG cases and 29,110 controls in the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database (NEIGHBORHOOD), which consists of 8 datasets with imputed genotypes to 5.6+ million markers. Associations with POAG were assessed in each dataset, and site-specific results were meta-analyzed using the inverse weighted variance method. Results: The genetic risk score was associated with self-reported ANM (P = 2.2 × 10–77) and predicted 4.8% of the variance in ANM. The ANM genetic risk score was not associated with POAG (Odds Ratio (OR) = 1.002; 95% Confidence Interval (CI): 0.998, 1.007; P = 0.28). No single genetic variant in the panel achieved nominal association with POAG (P ≥0.20). Compared to the middle 80 percent, there was also no association with the lowest 10th percentile or highest 90th percentile of genetic risk score with POAG (OR = 0.75; 95% CI: 0.47, 1.21; P = 0.23 and OR = 1.10; 95% CI: 0.72, 1.69; P = 0.65, respectively). Conclusions: A genetic risk score predicting 4.8% of ANM variation was not related to POAG; thus, genetic determinants of ANM are unlikely to explain the previously reported association between the two phenotypes. PMID:27760082

Comparative proteomic study in serum of patients with primary open-angle glaucoma and pseudoexfoliation glaucoma.

PubMed

González-Iglesias, Héctor; Álvarez, Lydia; García, Montserrat; Escribano, Julio; Rodríguez-Calvo, Pedro Pablo; Fernández-Vega, Luis; Coca-Prados, Miguel

2014-02-26

Alterations in the sera proteins between patients with Primary Open-Angle Glaucoma (POAG), Pseudoexfoliation Glaucoma (PEXG), and healthy controls were identified through a proven approach utilizing equalization of high-abundance serum proteins with ProteoMiner™, two-dimensional fluorescent difference gel electrophoresis (2D-DIGE), MALDI-TOF/TOF, and nanoLC-MS-MS. Quantitative immunoassays of the 17 most-differentially-altered proteins identified in this analysis confirmed that they were also over expressed in the intact serum of newly recruited glaucoma patients. Overall, this report identifies a panel of candidates for glaucoma biomarkers and supports their further validation in large population studies. Additionally, functional pathway analysis of these candidate proteins suggested that they are part of a network linked to regulating immune and inflammatory-related processes. The data have been deposited to the ProteomeXchange with identifier PXD000198. POAG and PEXG are major causes of age-related blindness in the world; however, treatment can be very effective if they are identified early on in the progression. Genetic linkage studies can only explain a limited number of cases, suggesting that these forms of glaucoma are multigenic in nature. Other important factors, such as modifier genes, epigenetic influences, environmental and dietary agents, and inflammatory and oxidative effects are also believed to affect the development of these diseases. The characterization of metabolic and/or proteins changes, for example in bodily fluids, before the clinical manifestation of glaucoma is of considerable relevance for its early diagnosis. In the present work, identification of over-expressed proteins in serum of glaucoma patients (POAG and PEXG) linked to immune and inflammatory processes supports the finding that changes in these pathways also manifest systemically in patients with these pathologies. This study provides a new basis to validate the identified proteins as biomarkers of glaucoma in a large-scale-multiplexed screening in sera. Copyright © 2013 Elsevier B.V. All rights reserved.

Age at natural menopause genetic risk score in relation to age at natural menopause and primary open-angle glaucoma in a US-based sample.

PubMed

Pasquale, Louis R; Aschard, Hugues; Kang, Jae H; Bailey, Jessica N Cooke; Lindström, Sara; Chasman, Daniel I; Christen, William G; Allingham, R Rand; Ashley-Koch, Allison; Lee, Richard K; Moroi, Sayoko E; Brilliant, Murray H; Wollstein, Gadi; Schuman, Joel S; Fingert, John; Budenz, Donald L; Realini, Tony; Gaasterland, Terry; Gaasterland, Douglas; Scott, William K; Singh, Kuldev; Sit, Arthur J; Igo, Robert P; Song, Yeunjoo E; Hark, Lisa; Ritch, Robert; Rhee, Douglas J; Gulati, Vikas; Havens, Shane; Vollrath, Douglas; Zack, Donald J; Medeiros, Felipe; Weinreb, Robert N; Pericak-Vance, Margaret A; Liu, Yutao; Kraft, Peter; Richards, Julia E; Rosner, Bernard A; Hauser, Michael A; Haines, Jonathan L; Wiggs, Janey L

2017-02-01

Several attributes of female reproductive history, including age at natural menopause (ANM), have been related to primary open-angle glaucoma (POAG). We assembled 18 previously reported common genetic variants that predict ANM to determine their association with ANM or POAG. Using data from the Nurses' Health Study (7,143 women), we validated the ANM weighted genetic risk score in relation to self-reported ANM. Subsequently, to assess the relation with POAG, we used data from 2,160 female POAG cases and 29,110 controls in the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database (NEIGHBORHOOD), which consists of 8 datasets with imputed genotypes to 5.6+ million markers. Associations with POAG were assessed in each dataset, and site-specific results were meta-analyzed using the inverse weighted variance method. The genetic risk score was associated with self-reported ANM (P = 2.2 × 10) and predicted 4.8% of the variance in ANM. The ANM genetic risk score was not associated with POAG (Odds Ratio (OR) = 1.002; 95% Confidence Interval (CI): 0.998, 1.007; P = 0.28). No single genetic variant in the panel achieved nominal association with POAG (P ≥0.20). Compared to the middle 80 percent, there was also no association with the lowest 10 percentile or highest 90 percentile of genetic risk score with POAG (OR = 0.75; 95% CI: 0.47, 1.21; P = 0.23 and OR = 1.10; 95% CI: 0.72, 1.69; P = 0.65, respectively). A genetic risk score predicting 4.8% of ANM variation was not related to POAG; thus, genetic determinants of ANM are unlikely to explain the previously reported association between the two phenotypes.

Cost of glaucoma treatment in a developing country over a 5-year period

PubMed Central

Lazcano-Gomez, Gabriel; Ramos-Cadena, María de los Angeles; Torres-Tamayo, Margarita; Hernandez de Oteyza, Alejandra; Turati-Acosta, Mauricio; Jimenez-Román, Jesús

2016-01-01

Abstract The aim of the study was to disclose a realistic estimate of primary open-angle glaucoma treatment, follow-up costs, and patients’ monthly glaucoma-economic burden in an ophthalmology hospital in Mexico City. Prospective survey of 462 primary open-angle glaucoma patients from 2007 to 2012 was carried out. Costs from visits, glaucoma follow-up studies, laser, and glaucoma surgical procedures were obtained from hospital pricings. Education, employment, and monthly income were interrogated. Total cost was divided into hypotensive treatment cost, nonpharmacologic treatment cost (laser and surgeries), and follow-up studies and consults. Average wholesale price for drugs analyzed was obtained from IMS Health data; monthly cost was calculated using: Monthly cost  = ([average wholesale price/number of drops per eye dropper] × number of daily applications) × 30 days. Patients were classified according to their glaucoma severity, and data were analyzed based on monthly income (average annual exchange rate: 12.85 Mexican pesos = 1 USD). The mean age was 70 ± 10 years, women = 81%, elementary school = 39%, and unemployed = 53%. Low-income group = 266 patients (57%), 146 with mild glaucoma; moderate-income group = 176 patients (38%), 81 with mild glaucoma; high-income group = 20 patients (4.3%), 10 with mild glaucoma. Patients’ monthly average economic burden in glaucoma treatment: low-income patients = 61.5%, moderate-income patients = 19.5%, and high-income patients = 7.9%. Glaucoma-economic burden is substantial not only for health systems, but for the family and the patient. Therefore, screening plans for earlier diagnosis, and health policies that lessen the cost of disease management and increase adherence to treatment, and reduce the prevalence of blindness attributed to glaucoma are essential. These would improve quality of life, reduce personal and national expenditure, and help increase national economy. PMID:27893669

Cost of glaucoma treatment in a developing country over a 5-year period.

PubMed

Lazcano-Gomez, Gabriel; Ramos-Cadena, María de Los Angeles; Torres-Tamayo, Margarita; Hernandez de Oteyza, Alejandra; Turati-Acosta, Mauricio; Jimenez-Román, Jesús

2016-11-01

The aim of the study was to disclose a realistic estimate of primary open-angle glaucoma treatment, follow-up costs, and patients' monthly glaucoma-economic burden in an ophthalmology hospital in Mexico City.Prospective survey of 462 primary open-angle glaucoma patients from 2007 to 2012 was carried out. Costs from visits, glaucoma follow-up studies, laser, and glaucoma surgical procedures were obtained from hospital pricings. Education, employment, and monthly income were interrogated. Total cost was divided into hypotensive treatment cost, nonpharmacologic treatment cost (laser and surgeries), and follow-up studies and consults. Average wholesale price for drugs analyzed was obtained from IMS Health data; monthly cost was calculated using: Monthly cost  = ([average wholesale price/number of drops per eye dropper] × number of daily applications) × 30 days.Patients were classified according to their glaucoma severity, and data were analyzed based on monthly income (average annual exchange rate: 12.85 Mexican pesos = 1 USD).The mean age was 70 ± 10 years, women = 81%, elementary school = 39%, and unemployed = 53%. Low-income group = 266 patients (57%), 146 with mild glaucoma; moderate-income group = 176 patients (38%), 81 with mild glaucoma; high-income group = 20 patients (4.3%), 10 with mild glaucoma. Patients' monthly average economic burden in glaucoma treatment: low-income patients = 61.5%, moderate-income patients = 19.5%, and high-income patients = 7.9%.Glaucoma-economic burden is substantial not only for health systems, but for the family and the patient. Therefore, screening plans for earlier diagnosis, and health policies that lessen the cost of disease management and increase adherence to treatment, and reduce the prevalence of blindness attributed to glaucoma are essential. These would improve quality of life, reduce personal and national expenditure, and help increase national economy.

Shotgun proteomics reveals specific modulated protein patterns in tears of patients with primary open angle glaucoma naïve to therapy.

PubMed

Pieragostino, Damiana; Agnifili, Luca; Fasanella, Vincenzo; D'Aguanno, Simona; Mastropasqua, Rodolfo; Di Ilio, Carmine; Sacchetta, Paolo; Urbani, Andrea; Del Boccio, Piero

2013-06-01

Primary open angle glaucoma (POAG) is one of the main causes of irreversible blindness worldwide. The pathogenesis of POAG is still unclear. Alteration and sclerosis of trabecular meshwork with changes in aqueous humor molecular composition seem to play the key role. Increased intraocular pressure is widely known to be the main risk factor for the onset and progression of the disease. Unfortunately, the early diagnosis of POAG still remains the main challenge. In order to provide insight into the patho-physiology of glaucoma, here we report a shotgun proteomics approach to tears of patients with POAG naïve to therapy. Our proteomics results showed 27 differential tear proteins in POAG vs. CTRL comparison (25 up regulated proteins in the POAG group and two unique proteins in the CTRL group), 16 of which were associated with inflammatory response, free radical scavenging, cell-to-cell signaling and interaction. Overall the protein modulation shown in POAG tears proves the involvement of biochemical networks linked to inflammation. Among all regulated proteins, a sub-group of 12 up-regulated proteins in naïve POAG patients were found to be down-regulated in medically controlled POAG patients treated with prostanoid analogues (PGA), as reported in our previous work (i.e., lipocalin-1, lysozyme C, lactotransferrin, proline-rich-protein 4, prolactin-inducible protein, zinc-alpha-2-glycoprotein, polymeric immunoglobulin receptor, cystatin S, Ig kappa chain C region, Ig alpha-2 chain C region, immunoglobulin J chain, Ig alpha-1 chain C region). In summary, our findings indicate that the POAG tears protein expression is a mixture of increased inflammatory proteins that could be potential biomarkers of the disease, and their regulation may be involved in the mechanism by which PGA are able to decrease the intraocular pressure in glaucoma patients.

The association between primary open-angle glaucoma and fall: an observational study.

PubMed

Tanabe, Sachiko; Yuki, Kenya; Ozeki, Naoki; Shiba, Daisuke; Tsubota, Kazuo

2012-01-01

Falls are among the most serious public health concerns for the elderly. Information conveyed via the visual sense is relevant to postural balance and movement, and proper visual function is essential to avoid falls. Here we investigated the prevalence of injurious falls among patients with primary open-angle glaucoma (POAG) who were more than 45 years old, compared with comparably aged healthy subjects. This is a cross-sectional study. Consecutive patients who visited the Tanabe Eye Clinic, Yamanashi, Japan between January 1 and March 30, 2009 were screened for eligibility by ophthalmic examination. A total of 117 control subjects (77 men, 40 women; aged 60.2 ± 7.5 years) who were free of ocular disease and 101 POAG patients (58 men, 43 women; aged 62.3 ± 8.7 years) were consecutively enrolled. Participants answered a questionnaire on injurious fall experience during the previous 10 years. The prevalence of injurious fall in subjects with POAG versus healthy controls was examined with Fisher's exact test. Adjusted odds ratios and 95% confidence intervals were estimated with logistic regression models for the subjects with POAG (factors: age, gender, mean deviation in the better eye or worse eye). The self-reported prevalence of injurious fall was 0.9% (1/117) in the control group and 6.9% (7/101) in the POAG group. The association between injurious fall and POAG was statistically significant (P = 0.026, Fisher's exact test). Within the POAG patients, the group reporting falls was significantly older and had a lower BMI, worse BCVA, and worse mean deviation in both the better and worse eye than the group reporting no falls. Worse mean deviation in the eye with the better visual field (odds ratios 0.75; 95% confidence intervals: 0.57 to 0.99; P = 0.036) was a significant risk factor for injurious falls in subjects with POAG. POAG was significantly associated with injurious falls.

Discovery and Functional Annotation of SIX6 Variants in Primary Open-Angle Glaucoma

PubMed Central

Allingham, R. Rand; Whigham, Benjamin T.; Havens, Shane; Garrett, Melanie E.; Qiao, Chunyan; Katsanis, Nicholas; Wiggs, Janey L.; Pasquale, Louis R.; Ashley-Koch, Allison; Oh, Edwin C.; Hauser, Michael A.

2014-01-01

Glaucoma is a leading cause of blindness worldwide. Primary open-angle glaucoma (POAG) is the most common subtype and is a complex trait with multigenic inheritance. Genome-wide association studies have previously identified a significant association between POAG and the SIX6 locus (rs10483727, odds ratio (OR) = 1.32, p = 3.87×10−11). SIX6 plays a role in ocular development and has been associated with the morphology of the optic nerve. We sequenced the SIX6 coding and regulatory regions in 262 POAG cases and 256 controls and identified six nonsynonymous coding variants, including five rare and one common variant, Asn141His (rs33912345), which was associated significantly with POAG (OR = 1.27, p = 4.2×10−10) in the NEIGHBOR/GLAUGEN datasets. These variants were tested in an in vivo Danio rerio (zebrafish) complementation assay to evaluate ocular metrics such as eye size and optic nerve structure. Five variants, found primarily in POAG cases, were hypomorphic or null, while the sixth variant, found only in controls, was benign. One variant in the SIX6 enhancer increased expression of SIX6 and disrupted its regulation. Finally, to our knowledge for the first time, we have identified a clinical feature in POAG patients that appears to be dependent upon SIX6 genotype: patients who are homozygous for the SIX6 risk allele (His141) have a statistically thinner retinal nerve fiber layer than patients homozygous for the SIX6 non-risk allele (Asn141). Our results, in combination with previous SIX6 work, lead us to hypothesize that SIX6 risk variants disrupt the development of the neural retina, leading to a reduced number of retinal ganglion cells, thereby increasing the risk of glaucoma-associated vision loss. PMID:24875647

Topical ocular sodium 4-phenylbutyrate rescues glaucoma in a myocilin mouse model of primary open-angle glaucoma.

PubMed

Zode, Gulab S; Bugge, Kevin E; Mohan, Kabhilan; Grozdanic, Sinisa D; Peters, Joseph C; Koehn, Demelza R; Anderson, Michael G; Kardon, Randy H; Stone, Edwin M; Sheffield, Val C

2012-03-01

Mutations in the myocilin gene (MYOC) are the most common known genetic cause of primary open-angle glaucoma (POAG). The purpose of this study was to determine whether topical ocular sodium 4-phenylbutyrate (PBA) treatment rescues glaucoma phenotypes in a mouse model of myocilin-associated glaucoma (Tg-MYOC(Y437H) mice). Tg-MYOC(Y437H) mice were treated with PBA eye drops (n = 10) or sterile PBS (n = 8) twice daily for 5 months. Long-term safety and effectiveness of topical PBA (0.2%) on glaucoma phenotypes were examined by measuring intraocular pressure (IOP) and pattern ERG (PERG), performing slit lamp evaluation of the anterior chamber, analyzing histologic sections of the anterior segment, and comparing myocilin levels in the aqueous humor and trabecular meshwork of Tg-MYOC(Y437H) mice. Tg-MYOC(Y437H) mice developed elevated IOP at 3 months of age when compared with wild-type (WT) littermates (n = 24; P < 0.0001). Topical PBA did not alter IOP in WT mice. However, it significantly reduced elevated IOP in Tg-MYOC(Y437H) mice to the level of WT mice. Topical PBA-treated Tg-MYOC(Y437H) mice also preserved PERG amplitudes compared with vehicle-treated Tg-MYOC(Y437H) mice. No structural abnormalities were observed in the anterior chamber of PBA-treated WT and Tg-MYOC(Y437H) mice. Analysis of the myocilin in the aqueous humor and TM revealed that PBA significantly improved the secretion of myocilin and reduced myocilin accumulation as well as endoplasmic reticulum (ER) stress in the TM of Tg-MYOC(Y437H) mice. Furthermore, topical PBA reduced IOP elevated by induction of ER stress via tunicamycin injections in WT mice. Topical ocular PBA reduces glaucomatous phenotypes in Tg-MYOC(Y437H) mice, most likely by reducing myocilin accumulation and ER stress in the TM. Topical ocular PBA could become a novel treatment for POAG patients with myocilin mutations.

Is high myopia a risk factor for visual field progression or disk hemorrhage in primary open-angle glaucoma?

PubMed

Nitta, Koji; Sugiyama, Kazuhisa; Wajima, Ryotaro; Tachibana, Gaku

2017-01-01

The purpose of this study was to clarify differences between highly myopic and non-myopic primary open-angle glaucoma (POAG) patients, including normal-tension glaucoma patients. A total of 269 POAG patients were divided into two groups: patients with ≥26.5 mm of axial length (highly myopic group) and patients with <24.0 mm of axial length (non-myopic group). We analyzed 53 highly myopic and 93 non-myopic POAG patients. Age at first visit of the highly myopic group was significantly less than that of the non-myopic group ( P <0.0001). Baseline intraocular pressures (IOPs) showed no significant differences. Follow-up IOPs of the non-myopic group were significantly lower than those of the highly myopic group ( P =0.0009). According to the mean deviation definition of progression, the cumulative probability of non-progression of visual field (VF) loss was significantly greater in the highly myopic group (10-year survival rate, 73.7%±6.8%) than in the non-myopic group (10-year survival rate, 46.3%±5.8%; log-rank test, P =0.0142). The occurrence of disk hemorrhage (DH) in the non-myopic group (1.60±3.04) was significantly greater than that in the highly myopic group (0.93±2.13, P =0.0311). The cumulative probability of DH was significantly lower in the highly myopic group (10-year survival rate, 26.4%±5.4%) than in the non-myopic group (10-year survival rate, 47.2%±6.6%, P =0.0413). Highly myopic POAG is considered as a combination of myopic optic neuropathy and glaucomatous optic neuropathy (GON). If GON is predominant, it has frequent DH and more progressive VF loss. However, when the myopic optic neuropathy is predominant, it has less DH and less progressive VF loss.

Comparison of Risk Factor Profiles for Primary Open-Angle Glaucoma Subtypes Defined by Pattern of Visual Field Loss: A Prospective Study.

PubMed

Kang, Jae H; Loomis, Stephanie J; Rosner, Bernard A; Wiggs, Janey L; Pasquale, Louis R

2015-04-01

We explored whether risk factor associations differed by primary open-angle glaucoma (POAG) subtypes defined by visual field (VF) loss pattern (i.e., paracentral or peripheral). We included 77,157 women in the Nurses' Health Study (NHS) and 42,773 men in the Health Professionals Follow-up Study (HPFS 1986-2010), and incident medical record confirmed cases of paracentral (n = 440) and peripheral (n = 865) POAG subtypes. We evaluated African heritage, glaucoma family history, body mass index (BMI), mean arterial blood pressure, diabetes mellitus, physical activity, smoking, caffeine intake, and alcohol intake. We used competing risk Cox regression analyses modeling age as the metameter and stratified by age, cohort, and event type. We sequentially identified factors with the least significant differences in associations with POAG subtypes ("stepwise down" approach with P for heterogeneity [P-het] < 0.10 as threshold). Body mass index was more inversely associated with the POAG paracentral VF loss subtype than the peripheral VF loss subtype (per 10 kg/m2; hazard ratio [HR] = 0.67 [95% confidence interval (CI): 0.52, 0.86] versus HR = 0.93 [95% CI: 0.78, 1.10]; P-het = 0.03) as was smoking (per 10 pack-years; HR = 0.92 [95% CI: 0.87, 0.98] versus HR = 0.98 [95% CI: 0.94, 1.01]; P-het = 0.09). These findings were robust in sensitivity analyses using a "stepwise up" approach (identify factors that showed the most significant differences). Nonheterogeneous (P-het > 0.10) adverse associations with both POAG subtypes were observed with glaucoma family history, diabetes, African heritage, greater caffeine intake, and higher mean arterial pressure. These data indicate that POAG with early paracentral VF loss has distinct as well as common determinants compared with POAG with peripheral VF loss.

[Transient elevation of intraocular pressure in primary open-angle glaucoma patients after automated visual field examination in the winter].

PubMed

Nishino, Kazuaki; Yoshida, Fujiko; Nitta, Akari; Saito, Mieko; Saito, Kazuuchi

2013-12-01

To evaluate retrospectively seasonal fluctuations of transient intraocular pressure (IOP) elevation after automated visual field examination in patients with primary open-angle glaucoma (POAG). We reviewed 53 consecutive patients with POAG who visited Kaimeido Ophthalmic and Dental Clinic from January 2011 to March 2013, 21 men and 32 women aged 67.7 +/- 11.2 years. The patients were divided into 4 groups, spring, summer, autumn, and winter according to the month of automated visual field examination and both eyes of each patient were enrolled. IOP was measured immediately after automated visual field examination (vf IOP) and compared with the average IOP from the previous 3 months (pre IOP) and with the average IOP from the following 3 months (post IOP) in each season. IOP elevation rate was defined as (vf IOP- pre IOP)/pre IOP x 100% and calculated for each season (paired t test). Additionally, the correlation between mean deviation (MD) and IOP elevation rate was evaluated (single regression analysis). Exclusion criteria were patients who received cataract surgery during this study or had a history of any previous glaucoma surgery. The automated visual field test was performed with a Humphrey field analyzer and the Central 30-2 FASTPAC threshold program. The average vf IOP was 14.5 +/- 2.5 mmHg, higher than pre IOP 13.8 +/- 2.4 mmHg (p < 0.0001) and the post IOP 13.8 +/- 2.2 mmHg (p < 0.0001). IOP elevation rate in each season was 4.1 11.6% in spring (n = 22, p = 0.18), 0.1 +/- 9.9% in summer (n = 16, p = 1.0), 5.0 +/- 13.8% in autumn (n = 30. p = 0.11), 10.6 +/- 8.8% in winter (n = 38, p < 0.0001). The MD was not correlated with IOP elevation rate (p = 0.17). Patients with POAG show a transient IOP elevation after automated visual field examination, especially in the winter but not in the summer.

Changes of visual-field global indices after cataract surgery in primary open-angle glaucoma patients.

PubMed

Seol, Bo Ram; Jeoung, Jin Wook; Park, Ki Ho

2016-11-01

To determine changes of visual-field (VF) global indices after cataract surgery and the factors associated with the effect of cataracts on those indices in primary open-angle glaucoma (POAG) patients. A retrospective chart review of 60 POAG patients who had undergone phacoemulsification and intraocular lens insertion was conducted. All of the patients were evaluated with standard automated perimetry (SAP; 30-2 Swedish interactive threshold algorithm; Carl Zeiss Meditec Inc.) before and after surgery. VF global indices before surgery were compared with those after surgery. The best-corrected visual acuity, intraocular pressure (IOP), number of glaucoma medications before surgery, mean total deviation (TD) values, mean pattern deviation (PD) value, and mean TD-PD value were also compared with the corresponding postoperative values. Additionally, postoperative peak IOP and mean IOP were evaluated. Univariate and multivariate logistic regression analyses were performed to identify the factors associated with the effect of cataract on global indices. Mean deviation (MD) after cataract surgery was significantly improved compared with the preoperative MD. Pattern standard deviation (PSD) and visual-field index (VFI) after surgery were similar to those before surgery. Also, mean TD and mean TD-PD were significantly improved after surgery. The posterior subcapsular cataract (PSC) type showed greater MD changes than did the non-PSC type in both the univariate and multivariate logistic regression analyses. In the univariate logistic regression analysis, the preoperative TD-PD value and type of cataract were associated with MD change. However, in the multivariate logistic regression analysis, type of cataract was the only associated factor. None of the other factors was associated with MD change. MD was significantly affected by cataracts, whereas PSD and VFI were not. Most notably, the PSC type showed better MD improvement compared with the non-PSC type after cataract surgery. Clinicians therefore should carefully analyze VF examination results for POAG patients with the PSC type.

Differential Protein Expression Profiles in Glaucomatous Trabecular Meshwork: An Evaluation Study on a Small Primary Open Angle Glaucoma Population.

PubMed

Micera, Alessandra; Quaranta, Luciano; Esposito, Graziana; Floriani, Irene; Pocobelli, Augusto; Saccà, Sergio Claudio; Riva, Ivano; Manni, Gianluca; Oddone, Francesco

2016-02-01

Primary open angle glaucoma (POAG) is a progressive optic neuropathy characterized by impaired aqueous outflow and extensive remodeling in the trabecular meshwork (TM). The aim of this study was to characterize and compare the expression patterns of selected proteins belonging to the tissue remodeling, inflammation and growth factor pathways in ex vivo glaucomatous and post-mortem TMs using protein-array analysis. TM specimens were collected from 63 white subjects, including 40 patients with glaucoma and 23 controls. Forty POAG TMs were collected at the time of surgery and 23 post-mortem specimens were from non-glaucomatous donor sclerocorneal tissues. Protein profiles were evaluated using a chip-based array consisting of 60 literature-selected antibodies. A different expression of some factors was observed in POAG TMs with respect to post-mortem specimens, either in abundance (interleukin [IL]10, IL6, IL5, IL7, IL12, IL3, macrophage inflammatory protein [MIP]1δ/α, vascular endothelial growth factor [VEGF], transforming growth factor beta 1 [TGFβ1], soluble tumor necrosis factor receptor I [sTNFRI]) or in scarcity (IL16, IL18, intercellular adhesion molecule 3 [ICAM3], matrix metalloproteinase-7 [MMP7], tissue inhibitor of metalloproteinase 1 [TIMP1]). MMP2, MMP7, TGFβ1, and VEGF expressions were confirmed by Western blot, zymography, and polymerase chain reaction. No difference in protein profile expression was detected between glaucomatous subtypes. The analysis of this small TM population highlighted some proteins linked to POAG, some previously reported and others of new detection (IL7, MIPs, sTNFαRI). A larger POAG population is required to select promising disease-associated biomarker candidates. This study was partially supported by the Fondazione Roma, the Italian Ministry of Health and the "National 5xMille 2010 tax donation to IRCCS-G.B. Bietti Foundation".

Changes in the retrobulbar hemodynamic parameters after decreasing the elevated intraocular pressure in primary open-angle glaucoma patients.

PubMed

Marjanović, Ivan; Martinez, Antonio; Marjanović, Marija; Milić, Natasa; Kontić, Djordje; Hentova-Senćanić, Paraskeva; Marković, Vujica; Bozić, Marija

2014-01-01

Ocular blood flow (OBF) disturbances could be involved both in the pathogenesis and in progression of glaucomatous damage. The aim of the study was to compare the retrobulbar hemodynamic parameters in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior cilliary arteries (SPCA) after decreasing the elevated intraocular pressure (IOP) in primary open-angle glaucoma (POAG) patients by using color Doppler imaging (CDI). We examined 60 patients (21 male and 39 female) with diagnosed and treated POAG. Thirty-nine patients had increased IOP (> 25 mm Hg). Peak-systolic velocity (PSV), end-diastolic velocity (EDV), Pourcelot resistance index (RI), and pulsatility index (PI) were assessed in the OA, CRA, and SPCA. IOP was measured both with the Goldmann Applanation tonometer (GAT) and with the Dynamic Contour tonometer (DCT), three times respectively. Ocular pulse amplitude (OPA) was measured using DCT. The retrobulbar parameters between the baseline and after IOP reduction showed no difference in measurements. After Bonferroni correction (p < or = 0.0056, alpha/9) statistical significance was recorded only in the following retrobulbar hemodynamic parameters; DCT (29.8 +/- 6.2 vs. 15.5 +/- 5.0), GAT (33.8 +/- 9.0 vs. 15.0 +/- 6.6) and OPA measurements (4.3 +/- 1.0 vs. 3.0 +/- 1.6), as compared to the baseline. There was no correlation between the changes in IOP measured with either DCT or GAT and changes in the hemodynamic parameters (p > 0.05 for all). Pearson correlation coefficient (95% CI) showed very good correlation for IOP measurements between DCT and GAT: at baseline 0.83 (0.71 to 0.90) and at the end 0.71 (0.55 to 0.83); p < 0.0001 for both measurements, but without any difference between them (p > 0.05). There was a lack of correlation between the changes in IOP measured with either DCT or GAT and the changes in the hemodynamic parameters.

Effect of dorzolamide and timolol on ocular blood flow in patients with primary open angle glaucoma and ocular hypertension

PubMed Central

Fuchsjäger-Mayrl, G; Wally, B; Rainer, G; Buehl, W; Aggermann, T; Kolodjaschna, J; Weigert, G; Polska, E; Eichler, H-G; Vass, C; Schmetterer, L

2005-01-01

Background: There is evidence that perfusion abnormalities of the optic nerve head are involved in the pathogenesis of glaucoma. There is therefore considerable interest in the effects of topical antiglaucoma drugs on ocular blood flow. A study was undertaken to compare the ocular haemodynamic effects of dorzolamide and timolol in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT). Methods: One hundred and forty patients with POAG or OHT were included in a controlled, randomised, double blind study in two parallel groups; 70 were randomised to receive timolol and 70 to receive dorzolamide for a period of 6 months. Subjects whose intraocular pressure (IOP) did not respond to either of the two drugs were switched to the alternative treatment after 2 weeks. Scanning laser Doppler flowmetry was used to measure blood flow in the temporal neuroretinal rim and the cup of the optic nerve head. Pulsatile choroidal blood flow was assessed using laser interferometric measurement of fundus pulsation amplitude. Results: Five patients did not respond to timolol and were changed to the dorzolamide group, and 18 patients changed from dorzolamide treatment to timolol. The effects of both drugs on IOP and ocular perfusion pressure were comparable. Dorzolamide, but not timolol, increased blood flow in the temporal neuroretinal rim (8.5 (1.6)%, p<0.001 versus timolol) and the cup of the optic nerve head (13.5 (2.5)%, p<0.001 versus timolol), and fundus pulsation amplitude (8.9 (1.3)%, p<0.001 versus timolol). Conclusions: This study indicates augmented blood flow in the optic nerve head and choroid after 6 months of treatment with dorzolamide, but not with timolol. It remains to be established whether this effect can help to reduce visual field loss in patients with glaucoma. PMID:16170119

Prevalence of Glaucoma in an Urban West African Population

PubMed Central

Budenz, Donald L.; Barton, Keith; Whiteside-de Vos, Julia; Schiffman, Joyce; Bandi, Jagadeesh; Nolan, Winifred; Herndon, Leon; Kim, Hanna; Hay-Smith, Graham; Tielsch, James M.

2014-01-01

Importance Multiple studies have found an increased prevalence, younger age at onset, and more severe course of glaucoma in people of African descent, but these findings are based on studies conducted outside Africa. Objective To determine the prevalence of glaucoma in an urban West African population of adults. Design and Setting A population-based, cross-sectional study of adults 40 years and older conducted from September 1, 2006, through December 31, 2008, from 5 communities in Tema, Ghana. Participants Participants from randomly selected clusters underwent a screening examination that consisted of visual acuity, frequency doubling perimetry, applanation tonometry, and optic disc photography. Participants who failed any of these tests were referred for complete examination, including gonioscopy, standard automated perimetry, and stereoscopic optic disc photography. Results A total of 6806 eligible participants were identified, and 5603 (82.3%) were enrolled in the study. The field examination referred 1869 participants (33.3%) to the clinic examination, and 1538 (82.2%) came for complete examination. A total of 362 participants were identified as having glaucoma of any type and category. Primary open-angle glaucoma was the underlying diagnosis in 342 participants (94.5%). The prevalence of primary open-angle glaucoma was 6.8% overall, increasing from 3.7% among those 40 to 49 years old to 14.6% among those 80 years and older, and was higher in men than in women in all age groups, with an overall male-female prevalence ratio of 1.5. Of the participants with glaucoma, 9 (2.5%) were blind using World Health Organization criteria, and only 12 (3.3%) were aware that they had glaucoma. Conclusions and Relevance The prevalence of glaucoma is higher in this urban West African population than in previous studies of people of East or South African and of non-African descent. Strategies to identify affected persons and effectively manage the burden of glaucoma are needed in West Africa. PMID:23538512

A comparison of the sensitivity of EQ-5D, SF-6D and TTO utility values to changes in vision and perceived visual function in patients with primary open-angle glaucoma

PubMed Central

2012-01-01

Background Economic viability of treatments for primary open-angle glaucoma (POAG) should be assessed objectively to prioritise health care interventions. This study aims to identify the methods for eliciting utility values (UVs) most sensitive to differences in visual field and visual functioning in patients with POAG. As a secondary objective, the dimensions of generic health-related and vision-related quality of life most affected by progressive vision loss will be identified. Methods A total of 132 POAG patients were recruited. Three sets of utility values (EuroQoL EQ-5D, Short Form SF-6D, Time Trade Off) and a measure of perceived visual functioning from the National Eye Institute Visual Function Questionnaire (VFQ-25) were elicited during face-to-face interviews. The sensitivity of UVs to differences in the binocular visual field, visual acuity and visual functioning measures was analysed using non-parametric statistical methods. Results Median utilities were similar across Integrated Visual Field score quartiles for EQ-5D (P = 0.08) whereas SF-6D and Time-Trade-Off UVs significantly decreased (p = 0.01 and p = 0.001, respectively). The VFQ-25 score varied across Integrated Visual Field and binocular visual acuity groups and was associated with all three UVs (P ≤ 0.001); most of its vision-specific sub-scales were associated with the vision markers. The most affected dimension was driving. A relationship with vision markers was found for the physical component of SF-36 and not for any dimension of EQ-5D. Conclusions The Time-Trade-Off was more sensitive than EQ-5D and SF-6D to changes in vision and visual functioning associated with glaucoma progression but could not measure quality of life changes in the mildest disease stages. PMID:22909264

Serum vitamin D status is associated with the presence but not the severity of primary open angle glaucoma.

PubMed

Goncalves, Aurélien; Milea, Dan; Gohier, Philippe; Jallet, Ghislaine; Leruez, Stéphanie; Baskaran, Mani; Aung, Tin; Annweiler, Cédric

2015-08-01

Vitamin D is involved in visual health and function. Our objective was to determine whether age-related vitamin D insufficiency was associated with the presence and the severity of primary open angle glaucoma (POAG) in a case-control study of older adults. Case-control study. One hundred fifty cases diagnosed with moderate-to-severe POAG (mean, 75.1 ± 8.5 years; 42.0% female) and 164 healthy controls (mean, 73.0 ± 7.9 years; 59.8% female) were included. POAG diagnosis was based on classical diagnostic criteria of optic nerve cupping and/or RNFL thinning, measured with optical coherence tomography. Severe POAG was defined as Humphrey visual field mean deviation (MD) worse than -12 dB. Vitamin D insufficiency was defined as serum 25OHD ≤ 75 nmol/L. Age, gender, mean arterial pressure, vitamin D supplementation, visual acuity, and intraocular pressure were used as potential confounders. POAG cases had lower mean serum 25OHD concentration than controls (42.9 ± 25.7 nmol/L versus 49.4 ± 29.5 nmol/L, P=0.039) and a greater prevalence of vitamin D insufficiency (90.7% versus 82.3%, P=0.032). Increased mean serum 25OHD concentrations were associated with lower POAG frequency, even after adjustment for potential confounders (OR=0.89 per 10 nmol/L of 25OHD, P=0.045). Similarly, vitamin D insufficiency was associated with POAG (OR=2.09, P=0.034). Among POAG cases, no 25OHD difference was observed between moderate and severe POAG cases (respectively, 39.2 ± 23.3 nmol/L versus 45.1 ± 26.7 nmol/L, P=0.188); and no between-group difference regarding the prevalence of vitamin D insufficiency (88.9% versus 94.0%, P=0.313). Decreased serum 25OHD concentration was associated with POAG. There was no 25OHD difference between moderate and severe POAG. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

A Nested Case Control Study of Plasma ICAM-1, E-Selectin and TNF Receptor 2 Levels, and Incident Primary Open-Angle Glaucoma

PubMed Central

Kang, Jae H.; Wiggs, Janey L.; Pasquale, Louis R.

2013-01-01

Purpose. To evaluate prediagnostic markers of endothelial dysfunction and inflammatory processes in primary open-angle glaucoma (POAG). Methods. Blood samples were collected from 1989 to 1990 in the Nurses' Health Study (women) and from 1993 to 1995 in the Health Professionals Follow-up Study (men), and medical-record confirmed incident POAG cases were identified (women: 229 cases and 455 controls; men: 116 cases and 228 controls). Controls were matched on cohort, age, race, ethnicity, cancer status, and date of blood collection. Plasma concentrations of ICAM-1, E-selectin, and soluble TNF receptor 2 (sTNF-R2), a marker related to TNF-α, were measured with ELISA assays. Cohort-specific multivariable conditional logistic regression model results were meta-analyzed. Results. We observed no associations with ICAM-1 or E-selectin. For sTNF-R2, the mean (SD) plasma levels (pg/mL) in cases and controls were 2888 (997) and 2993 (913), respectively, in women; and 2622 (664) and 2569 (688), respectively, in men. Pooled multivariable results showed no relation between sTNF-R2 levels and POAG. However, compared with the lowest tertile of sTNF-R2, the highest tertile showed a significant decreased risk of POAG in women (multivariable odds ratio [OR] = 0.58, 95% confidence interval [CI] = 0.36–0.93; Ptrend = 0.03) but not in men (Ptrend = 0.21; P for heterogeneity by sex = 0.03). Also, among women, the inverse association with sTNF-R2 was stronger with normal-tension glaucoma (NTG; maximum intraocular pressure <21 mm Hg at diagnosis): highest versus lowest tertile comparison OR = 0.29 (95% CI = 0.12–0.71; Ptrend = 0.007). Conclusions. In women, but not in men, higher sTNF-R2 levels at 6 to 8 years before diagnosis were inversely associated with POAG, but more strongly for NTG. PMID:23412091

Expression-associated polymorphisms of CAV1-CAV2 affect intraocular pressure and high-tension glaucoma risk

PubMed Central

Kim, Sewon; Kim, Kyunglan; Heo, Dong Won; Kim, Jong-Sung; Park, Chan Kee; Kim, Chang-sik

2015-01-01

Purpose The human CAV1-CAV2 locus has been associated with susceptibility to primary open-angle glaucoma in four studies of Caucasian, Chinese, and Pakistani populations, although not in several other studies of non-Korean populations. In this study with Korean participants, the CAV1-CAV2 locus was investigated for associations with susceptibility to primary open-angle glaucoma accompanied by elevated intraocular pressure (IOP), namely, high-tension glaucoma (HTG), as well as with IOP elevation, which is a strong risk factor for glaucoma. Methods Two single nucleotide polymorphisms (SNPs) were genotyped in 1,161 Korean participants including 229 patients with HTG and 932 healthy controls and statistically examined for association with HTG susceptibility and IOP. One SNP was rs4236601 G>A, which had been reported in the original study, and the other SNP was rs17588172 T>G, which was perfectly correlated (r2=1) with another reported SNP rs1052990. Expression quantitative trait loci (eQTL) analysis was performed using GENe Expression VARiation (Genevar) data. Results Both SNPs were associated with HTG susceptibility, but the rs4236601 association disappeared when adjusted for the rs17588172 genotype and not vice versa. The minor allele G of rs17588172 was associated significantly with 1.5-fold increased susceptibility to HTG (p=0.0069) and marginally with IOP elevation (p=0.043) versus the major allele T. This minor allele was also associated with decreased CAV1 and CAV2 mRNA in skin and adipose according to the Genevar eQTL analysis. Conclusions The minor allele G of rs17588172 in the CAV1-CAV2 locus is associated with decreased expression of CAV1 and CAV2 in some tissues, marginally with IOP elevation, and consequently with increased susceptibility to HTG. PMID:26015768

Survey of familial glaucoma shows a high incidence of cytochrome P450, family 1, subfamily B, polypeptide 1 (CYP1B1) mutations in non-consanguineous congenital forms in a Spanish population

PubMed Central

Millá, Elena; Mañé, Begoña; Duch, Susana; Hernan, Imma; Borràs, Emma; Planas, Ester; Dias, Miguel de Sousa; Carballo, Miguel

2013-01-01

Purpose To identify myocilin (MYOC) and cytochrome P450, family 1, subfamily B, polypeptide 1 (CYP1B1) mutations in a Spanish population with different clinical forms of familial glaucoma or ocular hypertension (OHT). Methods Index patients from 226 families participated in this study. Patients were diagnosed with familial glaucoma or OHT by complete ophthalmologic examination. Screening for MYOC mutations was performed in 207 index patients: 96 with adult-onset primary open-angle glaucoma (POAG), 21 with primary congenital glaucoma (PCG), 18 with juvenile-onset open-angle glaucoma (JOAG), five with Axenfeld-Rieger syndrome (ARS), and 67 with other types of glaucoma. One hundred two of the families (including all those in whom a MYOC mutation was detected) were also screened for CYP1B1 mutations: 45 POAG, 25 PCG, 21 JOAG, four ARS, and seven others. Results We examined 292 individuals (patients and relatives) with a positive family history of glaucoma or OHT. We identified two novel MYOC variants, p.Lys39Arg and p.Glu218Lys, in two families with POAG, and six previously reported MYOC mutations in seven families with POAG (four), JOAG (one), PCG (one), and normotensive glaucoma (one). CYP1B1 mutations were found in 16 index patients with PCG (nine), POAG (three), JOAG (two), and ARS (two). Conclusions The high percentage (9/25=36%) of mutations in CYP1B1 found in non-consanguineous patients with congenital glaucoma mandates genetic testing. However, the percentage of mutations (9/207=4.4%) in MYOC associated with glaucoma is relatively low in our population. The variable phenotype expression of glaucoma, even in families, cannot be explained with a digenic mechanism between MYOC and CYP1B1. PMID:23922489

Association of Baseline Anterior Segment Parameters With the Development of Incident Gonioscopic Angle Closure.

PubMed

Nongpiur, Monisha E; Aboobakar, Inas F; Baskaran, Mani; Narayanaswamy, Arun; Sakata, Lisandro M; Wu, Renyi; Atalay, Eray; Friedman, David S; Aung, Tin

2017-03-01

Baseline anterior segment imaging parameters associated with incident gonioscopic angle closure, to our knowledge, are unknown. To identify baseline quantitative anterior segment optical coherence tomography parameters associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline. Three hundred forty-two participants aged 50 years or older were recruited to participate in this prospective, community-based observational study. Participants underwent gonioscopy and anterior segment optical coherence tomography imaging at baseline and after 4 years. Custom image analysis software was used to quantify anterior chamber parameters from anterior segment optical coherence tomography images. Baseline anterior segment optical coherence tomography measurements among participants with gonioscopically open vs closed angles at follow-up. Of the 342 participants, 187 (55%) were women and 297 (87%) were Chinese. The response rate was 62.4%. Forty-nine participants (14.3%) developed gonioscopic angle closure after 4 years. The mean age (SD) at baseline of the 49 participants was 62.9 (8.0) years, 15 (30.6%) were men, and 43 (87.8%) were Chinese. These participants had a smaller baseline angle opening distance at 750 µm (AOD750) (0.15 mm; 95% CI, 0.12-0.18), trabecular iris surface area at 750 µm (0.07 mm2; 95% CI, 0.05-0.08), anterior chamber area (30 mm2; 95% CI, 2.27-3.74), and anterior chamber volume (24.32 mm2; 95% CI, 18.20-30.44) (all P < .001). Baseline iris curvature (-0.08; 95% CI, -0.12 to -0.04) and lens vault (LV) measurements (-0.29 mm; 95% CI, -0.37 to -0.21) were larger among these participants ( all P < .001). A model consisting of the LV and AOD750 measurements explained 38% of the variance in gonioscopic angle closure occurring at 4 years, with LV accounting for 28% of this variance. For every 0.1 mm increase in LV and 0.1 mm decrease in AOD750, the odds of developing gonioscopic angle closure was 1.29 (95% CI, 1.07-1.57) and 3.27 (95% CI, 1.87-5.69), respectively. In terms of per SD change in LV and AOD750, this translates to an odds ratio of 2.14 (95% CI, 2.48-12.34) and 5.53 (95% CI, 1.22-3.77), respectively. A baseline LV cut-off value of >0.56 mm had 64.6% sensitivity and 84.0% specificity for identifying participants who developed angle closure. These findings suggest that smaller AOD750 and larger LV measurements are associated with the development of incident gonioscopic angle closure after 4 years among participants with gonioscopically open angles at baseline.

Evaluation of circumferential angle closure using iridotrabecular contact index after laser iridotomy by swept-source optical coherence tomography.

PubMed

Cho, Hyun-Kyung; Ahn, Dongsub; Kee, Changwon

2017-05-01

To investigate the quantitative changes of circumferential angle closure after laser iridotomy (LI) using the iridotrabecular contact (ITC) index by Swept-Source optical coherence tomography (OCT). In this prospective observational study conducted in a hospital setting, 42 eyes of 36 patients (five males, 31 females) who underwent LI were included. The mean age was 65.00 ± 8.13 years old and the diagnosis included primary angle closure (PAC, 21 eyes), PAC suspect (16 eyes) and PAC glaucoma (five eyes). Optical coherence tomography (OCT) images were obtained pre-LI and at 1 week post-LI. In each image frame, the scleral spur (SS) and the ITC end-point were marked, from which the ITC index was calculated as a percentage of the angle closure across 360°. Measurements inspected before and after LI included: central anterior chamber depth (ACD), anterior chamber volume (ACV), lens vault (LV), nasal and temporal angle opening distance (AOD), angle recess area (ARA), trabecular-iris space area (TISA), trabecular-iris angle (TIA) at 500 μm and 750 μm from the SS and intraocular pressure (IOP). The ITC index and IOP decreased significantly after LI from 71.52 ± 26.29 to 35.31 ± 27.19 and from 20.64 ± 12.72 mmHg to 14.02 ± 3.49 mmHg, respectively (p < 0.001 and p < 0.001). Central ACD (1.94 ± 0.31 mm pre-LI) and LV (1.13 ± 0.32 mm pre-LI) did not show a significant change after LI (all p > 0.05), but ACV increased significantly after LI (p < 0.001). Most of the angle parameters except for nasal TIAs increased significantly after LI (all p < 0.05). The ITC index from patients with shallow anterior chamber angle showed a significant decrease after LI, but part of the angle closure was not relieved after LI. Other mechanisms besides pupillary block may play a role together in causing angle closure. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Optical Modeling and Polarization Calibration for CMB Measurements with Actpol and Advanced Actpol

NASA Technical Reports Server (NTRS)

Koopman, Brian; Austermann, Jason; Cho, Hsiao-Mei; Coughlin, Kevin P.; Duff, Shannon M.; Gallardo, Patricio A.; Hasselfield, Matthew; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; Hubmayr, Johannes;

Optical modeling and polarization calibration for CMB measurements with ACTPol and Advanced ACTPol

NASA Astrophysics Data System (ADS)

Koopman, Brian; Austermann, Jason; Cho, Hsiao-Mei; Coughlin, Kevin P.; Duff, Shannon M.; Gallardo, Patricio A.; Hasselfield, Matthew; Henderson, Shawn W.; Ho, Shuay-Pwu Patty; Hubmayr, Johannes; Irwin, Kent D.; Li, Dale; McMahon, Jeff; Nati, Federico; Niemack, Michael D.; Newburgh, Laura; Page, Lyman A.; Salatino, Maria; Schillaci, Alessandro; Schmitt, Benjamin L.; Simon, Sara M.; Vavagiakis, Eve M.; Ward, Jonathan T.; Wollack, Edward J.

2016-07-01

The Atacama Cosmology Telescope Polarimeter (ACTPol) is a polarization sensitive upgrade to the Atacama Cosmology Telescope, located at an elevation of 5190 m on Cerro Toco in Chile. ACTPol uses transition edge sensor bolometers coupled to orthomode transducers to measure both the temperature and polarization of the Cosmic Microwave Background (CMB). Calibration of the detector angles is a critical step in producing polarization maps of the CMB. Polarization angle offsets in the detector calibration can cause leakage in polarization from E to B modes and induce a spurious signal in the EB and TB cross correlations, which eliminates our ability to measure potential cosmological sources of EB and TB signals, such as cosmic birefringence. We calibrate the ACTPol detector angles by ray tracing the designed detector angle through the entire optical chain to determine the projection of each detector angle on the sky. The distribution of calibrated detector polarization angles are consistent with a global offset angle from zero when compared to the EB-nulling offset angle, the angle required to null the EB cross-correlation power spectrum. We present the optical modeling process. The detector angles can be cross checked through observations of known polarized sources, whether this be a galactic source or a laboratory reference standard. To cross check the ACTPol detector angles, we use a thin film polarization grid placed in front of the receiver of the telescope, between the receiver and the secondary reflector. Making use of a rapidly rotating half-wave plate (HWP) mount we spin the polarizing grid at a constant speed, polarizing and rotating the incoming atmospheric signal. The resulting sinusoidal signal is used to determine the detector angles. The optical modeling calibration was shown to be consistent with a global offset angle of zero when compared to EB nulling in the first ACTPol results and will continue to be a part of our calibration implementation. The first array of detectors for Advanced ACTPol, the next generation upgrade to ACTPol, will be deployed in 2016. We plan to continue using both techniques and compare them to astrophysical source measurements for the Advanced ACTPol polarization calibration.

Refractory open-angle glaucoma after neodymium-yttrium-aluminum-garnet laser lysis of vitreous floaters.

PubMed

Cowan, Lisa A; Khine, Kay T; Chopra, Vikas; Fazio, Doreen T; Francis, Brian A

2015-01-01

To illustrate 3 cases of chronic open-angle glaucoma secondary to the neodymium-yttrium-aluminum-garnet (Nd:YAG) laser vitreolysis procedure for symptomatic vitreous floaters. Observational case series. Location of the study was the Doheny Eye Institute. Three eyes of 2 patients who developed chronic open-angle glaucoma after Nd:YAG vitreolysis for symptomatic floaters presenting with very high intraocular pressure (IOP >40 mm Hg) were selected. The time from the laser treatment to the onset of elevated pressure ranges from 1 week to 8 months. There was no associated inflammation, steroid use, or other identifiable cause of chronic IOP elevation. All eyes were treated initially with glaucoma medication, followed by selective laser trabeculoplasty (SLT) and eventually glaucoma surgery (Trabectome) in 2 eyes for disease management. In all eyes, intraocular pressures were eventually stabilized within a normal pressure range from 18 to 38 months following Nd:YAG vitreolysis. At the latest follow-up post surgery, all eyes had intraocular pressures of 22 mm Hg or less with or without medications. Secondary open-angle glaucoma is a complication of Nd:YAG vitreolysis for symptomatic floaters that may present with an increase in intraocular pressure immediately, or many months after the surgery. Furthermore this complication may be permanent and require chronic medical therapy or glaucoma surgery. Copyright © 2015 Elsevier Inc. All rights reserved.

A target field design of open multi-purpose RF coil for musculoskeletal MR imaging at 3T.

PubMed

Gao, Fei; Zhang, Rui; Zhou, Diange; Wang, Xiaoying; Huang, Kefu; Zhang, Jue

2016-10-01

Musculoskeletal MR imaging under multi-angle situations plays an increasingly important role in assessing joint and muscle tissues system. However, there are still limitations due to the closed structures of most conventional RF coils. In this study, a time-harmonic target-field method was employed to design open multi-purpose coil (OMC) for multi-angle musculoskeletal MR imaging. The phantom imaging results suggested that the proposed OMC could achieve homogeneously distributed magnetic field and high signal-to-noise ratio (SNR) of 239.04±0.83 in the region of interest (ROI). The maximum temperature in the heating hazard test was 16°C lower than the standard regulation, which indicated the security of the designed OMC. Furthermore, to demonstrate the effectiveness of the proposed OMC for musculoskeletal MR imaging, especially for multi-angle imaging, a healthy volunteer was examined for MR imaging of elbow, ankle and knee using OMC. The in vivo imaging results showed that the proposed OMC is effective for MR imaging of musculoskeletal tissues at different body parts, with satisfied B1 field homogeneity and SNR. Moreover, the open structure of the OMC could provide a large joint movement region. The proposed open multi-purpose coil is feasible for musculoskeletal MR imaging, and potentially, it is more suitable for the evaluation of musculoskeletal tissues under multi-angle conditions. Copyright © 2016. Published by Elsevier Inc.

How do Dutch primary care providers overcome barriers to advance care planning with older people? A qualitative study.

PubMed

Glaudemans, Jolien J; de Jong, Anja E; Onwuteaka Philipsen, Bregje D; Wind, Jan; Willems, Dick L

2018-06-11

Few older people benefit from advance care planning (ACP), due to several barriers related to primary care professionals, such as insufficient knowledge, negative beliefs and a lack of time. Information on overcoming these barriers is limited. We assumed primary care professionals experienced in ACP with older patients are likely to have learned how to overcome these barriers. To investigate how Dutch primary care professionals experienced in ACP with older patients overcome these barriers. A qualitative study, based on semi-structured interviews, among a purposive sample of 14 Dutch primary care professionals experienced in ACP with older people. Transcripts were thematically analysed. We interviewed eight general practitioners (GPs), three nurses and three elderly care physicians, experienced in ACP with older people. Respondents overcame their own insufficient knowledge and skills, as well as their negative attitudes and beliefs by gaining experience through practicing ACP in their daily practices, exchanging and reflecting on those experiences with peers, pursuing continuing education, teaching and participating in research. To overcome patients' and families' lack of initiative and openness to ACP, respondents prepared them for further steps in ACP. To overcome a lack of time, respondents used tools and information communication technology, delegated parts of ACP to other primary care professionals, acquired financing and systematized documentation of ACP. Primary care professionals can overcome barriers to ACP with older patients by practicing, reflecting on experiences and pursuing continuing education, by preparing patients and involving family and by investing in support to approach ACP more efficiently.

Childhood glaucoma surgery in the 21st Century

PubMed Central

Papadopoulos, M; Edmunds, B; Fenerty, C; Khaw, P T

2014-01-01

Most children with glaucoma will require surgery in their lifetime, often in their childhood years. The surgical management of childhood glaucoma is however challenging, largely because of its greater potential for failure and complications as compared with surgery in adults. The available surgical repertoire for childhood glaucoma has remained relatively unchanged for many years with most progress owing to modifications to existing surgery. Although the surgical approach to childhood glaucoma varies around the world, angle surgery remains the preferred initial surgery for primary congenital glaucoma and a major advance has been the concept of incising the whole of the angle (circumferential trabeculotomy). Simple modifications to the trabeculectomy technique have been shown to considerably minimise complications. Glaucoma drainage devices maintain a vital role for certain types of glaucoma including those refractory to other surgery. Cyclodestruction continues to have a role mainly for patients following failed drainage/filtering surgery. Although the prognosis for childhood glaucoma has improved significantly since the introduction of angle surgery, there is still considerable progress to be made to ensure a sighted lifetime for children with glaucoma all over the world. Collaborative approaches to researching and delivering this care are required, and this paper highlights the need for more high-quality prospective surgical trials in the management of the childhood glaucoma. PMID:24924446

46 CFR 42.20-12 - Conditions of equilibrium.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., heel, and trim, is below the lower edge of any opening through which progressive flooding can take... angle of heel. The angle of heel due to unsymmetrical flooding does not exceed 15 degrees. If no part of the deck is immersed, an angle of heel of up to 17 degrees may be accepted. (d) Metacentric height...

46 CFR 42.20-12 - Conditions of equilibrium.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., heel, and trim, is below the lower edge of any opening through which progressive flooding can take... angle of heel. The angle of heel due to unsymmetrical flooding does not exceed 15 degrees. If no part of the deck is immersed, an angle of heel of up to 17 degrees may be accepted. (d) Metacentric height...

Characterization of single α-tracks by photoresist detection and AFM analysis-focus on biomedical science and technology

NASA Astrophysics Data System (ADS)

Falzone, Nadia; Myhra, Sverre; Chakalova, Radka; Hill, Mark A.; Thomson, James; Vallis, Katherine A.

2013-11-01

The interactions between energetic ions and biological and/or organic target materials have recently attracted theoretical and experimental attention, due to their implications for detector and device technologies, and for therapeutic applications. Most of the attention has focused on detection of the primary ionization tracks, and their effects, while recoil target atom tracks remain largely unexplored. Detection of tracks by a negative tone photoresist (SU-8), followed by standard development, in combination with analysis by atomic force microscopy, shows that both primary and recoil tracks are revealed as conical spikes, and can be characterized at high spatial resolution. The methodology has the potential to provide detailed information about single impact events, which may lead to more effective and informative detector technologies and advanced therapeutic procedures. In comparison with current characterization methods the advantageous features include: greater spatial resolution by an order of magnitude (20 nm) detection of single primary and associated recoil tracks; increased range of fluence (to 2.5 × 109 cm-2) sensitivity to impacts at grazing angle incidence; and better definition of the lateral interaction volume in target materials.

Regulation of TBK1 activity by Optineurin contributes to cell cycle-dependent expression of the interferon pathway.

PubMed

Weil, Robert; Laplantine, Emmanuel; Génin, Pierre

2016-06-01

The innate immune system has evolved to detect and neutralize viral invasions. Triggering of this defense mechanism relies on the production and secretion of soluble factors that stimulate intracellular antiviral defense mechanisms. The Tank Binding Kinase 1 (TBK1) is a serine/threonine kinase in the innate immune signaling pathways including the antiviral response and the host defense against cytosolic infection by bacteries. Given the critical roles of TBK1, important regulatory mechanisms are required to regulate its activity. Among these, Optineurin (Optn) was shown to negatively regulate the interferon response, in addition to its important role in membrane trafficking, protein secretion, autophagy and cell division. As Optn does not carry any enzymatic activity, its functions depend on its precise subcellular localization and its interaction with other proteins, especially with components of the innate immune pathway. This review highlights advances in our understanding of Optn mechanisms of action with focus on the relationships between Optn and TBK1 and their implication in host defense against pathogens. Specifically, how the antiviral immune system is controlled during the cell cycle by the Optn/TBK1 axis and the physiological consequences of this regulatory mechanism are described. This review may serve to a better understanding of the relationships between the different functions of Optn, including those related to immune responses and its associated pathologies such as primary open-angle glaucoma, amyotrophic lateral sclerosis and Paget's disease of bone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Open top culverts as an alternative drainage system to minimize ecological effects in earth roads.

NASA Astrophysics Data System (ADS)

García, Jose L.; Elorrieta, Jose; Robredo, Jose C.; García, Ricardo; García, Fernando; Gimenez, Martin C.

2013-04-01

During the last fifteen years a research team from School of Forestry at the Technical University of Madrid (Spain) has developed several competitive research projects regarding forest roads and open top culverts. A first approach was established with a prototype of 7 meters length in a hydraulic channel at the laboratory determining main parameters of different open top culverts in relation to different sizes of gravels and the self washing properties relationship with different slopes up to 8 %. The curves obtained may help to properly install these drainage systems avoiding maintenance costs. In addition more targeted pilot studies were developed in different forest earth roads in center and north Spain. The construction of the stations under study was financed by the U.P.M and the R&D National Plan. The main outcomes relates the low variation of humidity in a 20 m. wide range at both sides of the open top culverts and several considerations relating the angle of installation, the spacing of such drainage systems and the benefits against rilling along the roads. Also the erosion produced downhill was established and some construction methods to avoid adverse ecological effects. The diffusion of results includes congresses and a small booklet with a great acceptance in forestry services. Also a patent (ES 2 262 437) of an advanced model has been registered.

Experimental study on the effect of nozzle hole-to-hole angle on the near-field spray of diesel injector using fast X-ray phase-contrast imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xusheng; Moon, Seoksu; Gao, Jian

Fuel atomization and vaporization process play a critical role in determining the engine combustion and emission. The primary near-nozzle breakup is the vital link between the fuel emerging from the nozzle and the fully atomized spray. In this study, the near-nozzle spray characteristics of diesel injector with different umbrella angle (UA) were investigated using high-speed X-ray phase-contrast imaging and quantitative image processing. A classic ‘dumbbell’ profile of spray width (SW) composed of three stages: opening stage, semisteady stage and closing stage. The SW peak of two-hole injectors was more than twice of that of single-hole injector at the opening andmore » closing stages, corresponding to the hollow-cone spray. This indicated the vortex flow was formed with the increase of the UA. The higher injection pressure had little influence on the SW while led to earlier breakup closer to the nozzle. Significant fuel effect on the SW at higher needle lift was found. However, this effect could be neglect at lower needle lift due to the leading role of internal flow and cavitation on the near-field spray characteristics. In addition, the morphology-based breakup process was observed, which highlighted the important effect of internal flow on the spray development. The possibility of using hollow-cone spray in diesel injector was also discussed.« less

Dental and skeletal components of Class II open bite treatment with a modified Thurow appliance

PubMed Central

Jacob, Helder Baldi; dos Santos-Pinto, Ary; Buschang, Peter H.

2014-01-01

Introduction Due to the lack of studies that distinguish between dentoalveolar and basal changes caused by the Thurow appliance, this clinical study, carried out by the School of Dentistry - State University of São Paulo/Araraquara, aimed at assessing the dental and skeletal changes induced by modified Thurow appliance. Methods The sample included an experimental group comprising 13 subjects aged between 7 and 10 years old, with Class II malocclusion and anterior open bite, and a control group comprising 22 subjects similar in age, sex and mandibular plane angle. Maxillary/mandibular, horizontal/vertical, dental/skeletal movements (ANS, PNS, U1, U6, Co, Go, Pog, L1, L6) were assessed, based on 14 landmarks, 8 angles (S-N-ANS, SNA, PPA, S-N-Pog, SNB, MPA, PP/MPA, ANB) and 3 linear measures (N-Me, ANS-Me, S-Go). Results Treatment caused significantly greater angle decrease between the palatal and the mandibular plane of the experimental group, primarily due to an increase in the palatal plane angle. ANB, SNA and S-N-ANS angles significantly decreased more in patients from the experimental group. PNS was superiorly remodeled. Lower face height (ANS-Me) decreased in the experimental group and increased in the control group. Conclusions The modified Thurow appliance controlled vertical and horizontal displacements of the maxilla, rotated the maxilla and improved open bite malocclusion, decreasing lower facial height. PMID:24713556

The Properties of Extragalactic Radio Jets

NASA Astrophysics Data System (ADS)

Finke, Justin

2018-01-01

I show that by assuming a standard Blandford-Konigl jet, it is possible to determine the speed (bulk Lorentz factor) and orientation (angle to the line of sight) of self-similar parsec-scale blazar jets by using four measured quantities: the core radio flux, the extended radio flux, the magnitude of the core shift between two frequencies, and the apparent jet opening angle. Once the bulk Lorentz factor and angle to the line of sight of a jet are known, it is possible to compute their Doppler factor, magnetic field, and intrinsic jet opening angle. I use data taken from the literature and marginalize over nuisance parameters associated with the electron distribution and equipartition, to compute these quantities, albeit with large errors. The results have implications for the resolution of the TeV BL Lac Doppler factor crisis and the production of jets from magnetically arrested disks.

Detailed statistical contact angle analyses; "slow moving" drops on inclining silicon-oxide surfaces.

PubMed

Schmitt, M; Groß, K; Grub, J; Heib, F

2015-06-01

Contact angle determination by sessile drop technique is essential to characterise surface properties in science and in industry. Different specific angles can be observed on every solid which are correlated with the advancing or the receding of the triple line. Different procedures and definitions for the determination of specific angles exist which are often not comprehensible or reproducible. Therefore one of the most important things in this area is to build standard, reproducible and valid methods for determining advancing/receding contact angles. This contribution introduces novel techniques to analyse dynamic contact angle measurements (sessile drop) in detail which are applicable for axisymmetric and non-axisymmetric drops. Not only the recently presented fit solution by sigmoid function and the independent analysis of the different parameters (inclination, contact angle, velocity of the triple point) but also the dependent analysis will be firstly explained in detail. These approaches lead to contact angle data and different access on specific contact angles which are independent from "user-skills" and subjectivity of the operator. As example the motion behaviour of droplets on flat silicon-oxide surfaces after different surface treatments is dynamically measured by sessile drop technique when inclining the sample plate. The triple points, the inclination angles, the downhill (advancing motion) and the uphill angles (receding motion) obtained by high-precision drop shape analysis are independently and dependently statistically analysed. Due to the small covered distance for the dependent analysis (<0.4mm) and the dominance of counted events with small velocity the measurements are less influenced by motion dynamics and the procedure can be called "slow moving" analysis. The presented procedures as performed are especially sensitive to the range which reaches from the static to the "slow moving" dynamic contact angle determination. They are characterised by small deviations of the computed values. Additional to the detailed introduction of this novel analytical approaches plus fit solution special motion relations for the drop on inclined surfaces and detailed relations about the reactivity of the freshly cleaned silicon wafer surface resulting in acceleration behaviour (reactive de-wetting) are presented. Copyright © 2014 Elsevier Inc. All rights reserved.