Home About us Contact
|
Home About us Contact | ||
|
|
||
Lens
Kinds of Lens Terms modified by Lens Selected AbstractsTHICKENING THE DISCUSSION: INSPECTING CONSTRUCTIVIST THEORIES OF KNOWLEDGE THROUGH A JAMESIAN LENSEDUCATIONAL THEORY, Issue 1 2002Bradford S. Woods First page of article [source] Process Cost Comparison for Conventional and Near-Net-Shape Cermet Fabrication,ADVANCED ENGINEERING MATERIALS, Issue 3 2010Yuhong Xiong Tungsten carbide,cobalt (WC,Co) is a widely used cermet that is generally fabricated into bulk parts via conventional powder metallurgy (P/M) methods. Because this material (and other cermets) is very hard and wear resistant, diamond grinding is generally required to fabricate complex parts. As an alternative, studies have shown the Laser Engineering Net Shaping (LENS) process to be a technically feasible method, allowing for fabrication of near-net-shape parts. The economic trade-offs, however, have not been previously characterized. In this work, technical cost modeling (TCM) is applied to compare the costs of fabricating WC,Co parts with the P/M process to those of the LENS process. Cost drivers are identified and sensitivity analysis is conducted. Results reveal that the uncertainty in functional unit has a significant effect on relative process costs, and the cost is sensitive to order size only if less than ten parts are produced. It is concluded that the LENS process is economically preferable if part size is small or part shape is complex. The P/M process is more suitable to produce large parts in simple shapes. [source] Processing of Bulk Alumina Ceramics Using Laser Engineered Net ShapingINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 3 2008Vamsi Krishna Balla Application of rapid prototyping (RP) in ceramics manufacturing is motivated by advances in engineering ceramics where attaining complex shapes using traditional processing is difficult. Laser Engineered Net Shaping (LENSÔ), a commercial RP process, is used to fabricate dense, net-shaped structures of ,-Al2O3. Shapes such as cylinder, cube, and gear have been fabricated successfully with 10,25 mm section sizes. As-processed structures show anisotropy in mechanical properties with a high compressive strength normal to the build direction and columnar grains along the build direction. Heat treatment did not alter strength and anisotropy, but increased the grain size from 6 to 200 ,m and hardness from 1550 to 1700 Hv. [source] Compositionally Graded Aluminum Oxide Coatings on Stainless Steel Using Laser ProcessingJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 7 2007Partha P. Bandyopadhyay A 1.5 mm thick fully dense alumina coating with a composition gradient from 100% Ni,20 wt% Cr at the substrate to 100% alumina on top has been developed on a 316 stainless steel sheet using Laser Engineered Net Shaping (LENSÔ). The gradient coatings showed hardness in the range of 1800,2000 Hv, one of the highest reported so far due to high-density layers. During laser deposition, ,-Al2O3 found to grow along the deposition direction with coarse columnar structure. The inherent advantage of this approach is to control simultaneously both location and composition leading to better interfacial properties of coatings. [source] THROUGH A DIFFERENT LENS: RETHINKING THE ROLE OF SEXUAL DIFFERENCE IN THE THEOLOGY OF HANS URS VON BALTHASARMODERN THEOLOGY, Issue 1 2009BARBARA K. SAIN Sexual difference plays a pivotal role in Balthasar's thought, as an analogy for the Trinity and as an analogy for the relation between Christ and the church. This essay examines the influence of the analogy of being on his interpretations of these analogies, his understanding of created masculinity, and his use of the language of sexual difference for the Holy Spirit. Ultimately many of Balthasar's best insights about human love as an analogy for divine love can be retained without connecting femininity uniquely with creation, and his trinitarian theology provides the best interpretive key for doing so. [source] THE EXTERNAL OBSERVER AND THE LENS OF THE PATIENT-ANALYST MATCHTHE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 2 2002Judy L. Kantrowitz A focus on the match between patient and analyst places attention on the dynamic effect of the interaction of character and conflict of both participants on the process that evolves between them. Match is neither a predictive nor static concept. Rather it refers to an unfolding transaction that itself shifts and changes during the course of analytic work. The treating analyst's perception of the effect of this match is by necessity limited by the analyst's own blind spots and other countertransference phenomena. Reporting the analyst's clinical experience to an analytically trained observer, external to the dyad, may broaden the analyst's perspective. Using the lens of the match, a colleague in the role of supervisor, consultant or peer can provide feedback from which the analyst may acquire insight. As a result of this process, the influence that the participants' similarities and differences have upon each other becomes clear to the analyst. This awareness, in turn, may lead the analyst to appreciate the effect of the analyst's stance of distance or closeness and to evaluate whether at this phase of treatment it is beneficial or detrimental to the analytic process. Clinical illustrations of the effect of the external observer's feedback in relation to the patient,analyst match are provided. [source] FROM WOMEN'S WORK TO THE UMBILICAL LENS: MARY KELLY'S EARLY FILMSART HISTORY, Issue 1 2008SIONA WILSON This essay presents a historical and theoretical account of Mary Kelly's formative involvement in experimental filmmaking in Britain during the early- to mid-1970s. The argument develops by tracing the complex interconnections between Kelly's political engagement with Marxist-feminism and her theoretical involvement with psychoanalysis and film theory. After discussing Kelly's participation in the Berwick Street Film Collective's Night Cleaners (1975) and the London Women's Film Group's Women of the Rhondda (1973), I present a sustained close reading of the artist's first solo work, the film loop installation Antepartum (1974). I argue that Antepartum interpellates the spectator into a feminine subject position. This reading of the film draws upon recent post-Lacanian feminist scholarship in philosophical ethics that focuses on the intrauterine relation. Antepartum offers a politically informed aesthetic experiment that prefigures some of these insights. [source] Beyond the Biblical Impasse: Homosexuality Through the Lens of Theological AnthropologyDIALOG, Issue 1 2005Gwen B. Sayler Abstract:, What does the Bible say about homosexuality? The argument developed in this article demonstrates that the five biblical texts often cited as "proof" that the Bible condemns homosexuality reflect a theological anthropology that is challenged within Scripture itself and that has been determined by the church to be contextual rather than binding in relation to other debated issues. By bringing the theological anthropology reflected in the five texts into conversation with contrasting biblical anthropologies, it becomes possible to re-frame the contemporary conversation on homosexuality in terms of discerning which biblical theological anthropology will be considered authoritative for the church in the 21st century. [source] Response to Sayler Liturgical Texts, Ritual Power, and God's Glory: The Deconstruction of a Homosexual Identity through the Lens of a Doxological AnthropologyDIALOG, Issue 1 2005Amy C. Schifrin Abstract:, Looking at the scriptures as that which bear witness to a doxological anthropology, this essay responds to Gwen Sayler's article, "Beyond the Biblical Impasse: Homosexuality through the Lens of Theological Anthropology." This essay argues that the approach to the church's decision concerning the ordination of open and active self-identified homosexuals and the blessing of same-sex homoerotic relationships needs to be based on the sacramentality of the Creator's design of male and female and the doxological anthropology present in the apostolic witness. It examines the meaning of ritualizing the complementarity of male and female as the patterning by which humanity understands its source and its destiny. [source] Resistance as a Lens for Understanding the International Preschool MovementHISTORY OF EDUCATION QUARTERLY, Issue 2 2009Barbara Beatty No abstract is available for this article. [source] Design of a Singlet Lens and the Corresponding Aberration Correction Approaches for Cell Phone CameraIEEJ TRANSACTIONS ON ELECTRICAL AND ELECTRONIC ENGINEERING, Issue 4 2010Yupeng Zhang Member Abstract A singlet lens model that is designed for future cell phone camera is discussed. The proposed lens model unavoidably introduces significant optical aberration because of its high field angle (maximum field angle 48°). To correct the aberrations, traditional paraxial aberration and third-order Seidel aberration are no longer applicable because the accuracy will decline dramatically when the field angle reaches a high value. In this paper, the main objective is to find an improved first-order aberration equation and an improved third-order Seidel aberration equation using field-dependent coefficients to correct lateral chromatic aberration (LAT) and distortion, respectively, for a high-field-angle singlet lens. The simulation results suggest that improved higher order aberration equations are more accurate to represent real aberrations than the lower order case. However, the chromatic aberration is still visible in the resultant images even though LAT is corrected, because of the differences of blur between different colors caused by axial chromatic aberration (AX) and other monochromatic aberrations such as field curvature. This poses a new research topic as our future work. Copyright © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [source] Looking through the Lens of Gender: A Postmodern Critique of a Modern Housing ParadigmJOURNAL OF INTERIOR DESIGN, Issue 2 2002Lucinda Kaukas Havenband M.A., M.Phil. ABSTRACT The shift from a modern to postmodern paradigm has dramatically impacted the nature and content of academic inquiry and has opened new categories and methods for research. Interior design has been traditionally critiqued on the basis of aesthetics, formal qualities, function, health and safety, and social/behavioral factors. A postmodern critique expands that criteria to include analysis of how designs may be inscribed with particular ideologies and meanings and consideration of how these meanings may empower or disempower certain groups, or philosophies. In a feminist critique, that analysis considers specifically the ideology of gender. This paper will demonstrate the use of the postmodern deconstructive method of "close reading" in a feminist critique of the Case Study program, a paradigm for modern housing in postwar America. A close reading makes the assumption that the text is not neutral and attempts to discover its biases by thoroughly examining how information has been edited, framed, explained, and constructed. Through this method every aspect of the design process as it has been documented will be scrutinized as texts to examine ideas about roles for women that are constructed through this method; it will not only demonstrate how ideological issues, specifically in this case about gender, can be inscribed within our designs for built spaces, but also provide a greater awareness of our ability as designers to perpetuate, create, or eliminate stereotypes. [source] Social Justice as a Wider Lens of Support for Childbearing WomenJOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 3 2010M. Cynthia Logsdon ABSTRACT The ecological model is used as a framework for applying social justice concepts to the care of childbearing women and families. In this model, the environment of childbearing women has 3 distinct levels: macrosystem, mesosystem, and microsystem. Two scenarios are described and examples of nursing actions to promote social justice at each level are provided. This article demonstrates how maternal/infant nursing practice can be expanded to promote health equities, social justice, and support. [source] Interpreting the U.S. Human Trafficking Debate Through the Lens of Symbolic PoliticsLAW & POLICY, Issue 3 2007BARBARA ANN STOLZ By enacting the Trafficking Victims Protection Act of 2000, U.S. policymakers acknowledged trafficking in persons as criminal behavior, punishable under federal law. The legislation was developed through the congressional policy-making process, usually studied from the perspective of who gets what, when, and how. To expand our understanding of criminal justice policymaking, this article analyzes the act from an alternative perspective,symbolic politics. It examines how the act performs symbolic functions identified in the criminal justice literature,reassuring the law abiding/threatening the lawbreaker, communicating a moral message, providing a model for the states, and educating about a problem. [source] A Typology of Organizational Membership: Understanding Different Membership Relationships Through the Lens of Social ExchangeMANAGEMENT AND ORGANIZATION REVIEW, Issue 3 2009Christina L. Stamper abstract Using a social exchange perspective and responding to prior calls to separate resources exchanged from the relationship between parties, we develop a relationship typology based on rights and responsibilities arguments. We begin with the idea that various levels and types of rights and responsibilities are the exchange currency utilized by the employer and employee, respectively. Further, the degree to which an organization grants rights to an individual and the degree to which the individual voluntarily accepts responsibilities results in four distinct organizational membership profiles (i.e., peripheral, associate, detached, and full). We believe this membership typology is an important theoretical mechanism that may be used to link the exchange between the employee and employer (as represented by psychological contracts) to psychological attachment (as represented by perceived membership) between these two parties. Specifically, members in each profile will tend to have certain kinds of psychological attachments to the organization, causing them to (i) perceive membership in certain ways and (ii) behave in a manner consistent with that perception. The article concludes by discussing the implications of the propositions for both researchers and practitioners, as well as making suggestions for future research efforts. [source] Negotiating a New Role in a Gendered Order: A Cultural LensNEGOTIATION AND CONFLICT MANAGEMENT RESEARCH, Issue 1 2009Karen Golden-Biddle Abstract This article examines how advocates for the nurse practitioner (NP) role negotiated its implementation in a large urban health system that differentiates nursing from medicine on the basis of gender. Using a cultural perspective, analyses show how advocates envisioned the NP role as liminal,neither traditional nursing nor medical,and as expanding the boundaries of nursing work through appropriation of some medical work. Four key negotiation strategies are profiled that advocates used to successfully implement and sustain this role in most settings. The conclusion examines whether and how this new role altered or maintained the gendered arrangements and more generally points to the significance of liminal phenomena in producing fundamental change. [source] A look at Nursing Leadership Through the Lens of a DancerNURSING FORUM, Issue 1 2003Mary O'Connor RN First page of article [source] Microbial contamination of contact lenses and lens care accessories of soft contact lens wearers (university students) in Hong KongOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 1 2007M. S. Yung Abstract Purpose:, This study aimed to examine the rates of microbial contamination, and identify contaminants associated with contact lenses and lens care accessories used by a group of young contact lens wearers. Methods:, Collected contact lenses, lens cases, and lens care solutions were studied by bacterial culture. Contamination rates of these samples were recorded and compared with those reported in previous studies. Results:, Of the samples tested, 9% of lens extracts, 34% of case extracts and 11% of solution samples were contaminated with ocular pathogenic microorganisms. Serratia spp., Staphylococcus aureus and coagulase-negative staphylococci were the most common microorganisms isolated. Lens cases were the most frequently contaminated item. Lens cases also yielded the widest range of bacterial isolates. Contact lenses used by occasional wearers were associated with a higher contamination rate. Using either saline or multipurpose solution to rinse lenses before use appeared to be effective in reducing incidence of contamination. Conclusion:, Our findings demonstrate that contact lenses and lens care accessories are not well maintained by contact lens wearers. Regular reviews and reinforcement of lens care procedures for the usage and care of contact lenses and lens care accessories is therefore important and essential. [source] Potential pitfalls on the road to a process-managed organization (PMO), Part 1: The organization as system lensPERFORMANCE IMPROVEMENT, Issue 4 2009Geary A. Rummler Process design and improvement over the past 20 years have yielded great gains in customer satisfaction and cost containment in organizations throughout the world. This article presents what we call the Organizations as a Systems Lens. It provides a way of looking at organizations essential to being process centered. We present a powerful framework called the Processing System Hierarchy, which makes it quite clear what must be done to successfully travel the road to the process-managed organization. [source] Effects of Light Exposure and Use of Intraocular Lens on Retinal Pigment Epithelial Cells In VitroPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2009Sheng Hui To investigate the effect of a blue light-filtering intraocular lens (IOL) and a UV-absorbing IOL on light-induced damage to retinal pigment epithelial (RPE) cells laden with the lipofuscin fluorophore N -retinylidene- N -retinylethanolamine (A2E), A2E-laden RPE cells were exposed to white light which was filtered by either a blue light-filtering IOL or a UV-absorbing IOL. After 30 min of illumination the cell viability and the level of reactive oxygen species (ROS), free glutathione (GSH), vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) were determined. In the absence of an IOL, the white light exposure decreased cell viability to 37.2% of the nonirradiated control. The UV-absorbing IOL tended to reduce light-induced cell death; however, the decrease was not significant. The blue light-filtering IOL significantly attenuated light-induced cell damage, increasing cell viability to 79.5% of the nonirradiated control. The presence of the blue light-filtering IOL significantly increased GSH and PEDF levels, and decreased ROS and VEGF levels. This study suggests that a blue light-filtering IOL may be more protective against A2E-induced light damage and inhibit more light-induced ROS and VEGF production than a conventional UV-absorbing IOL. [source] Effect of Two Different UVA Doses on the Rabbit Cornea and LensPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2009ejka, estmír The aim of the present paper was to examine the irradiation effect of two doses of UVA rays (365 nm) on the rabbit cornea and lens. Corneas of anesthetized adult albino rabbits were irradiated with UVA rays for 5 days (daily dose 1.01 J cm,2 in one group of rabbits and daily dose 2.02 J cm,2 in the second group of animals). The third day after the last irradiation, the rabbits were killed, and their eyes were employed for spectrophotometrical, biochemical and immunohistochemical investigations. Normal eyes served as controls. Absorption spectra of the whole corneal centers were recorded over the UV,VIS (visible) spectral range. Levels of antioxidant and prooxidant enzymes, nitric oxide synthases and nitric oxide (indirectly measured as nitrate concentration) were investigated in the cornea. Malondialdehyde, a byproduct of lipid peroxidation, was examined in the cornea and lens. The results show that the staining for endothelial nitric oxide synthase was more pronounced in corneas irradiated with the higher UVA dose. Otherwise, UVA rays at either dose did not significantly change corneal light absorption properties and did not cause statistically significant metabolic changes in the cornea or lens. In conclusion, UVA rays at the employed doses did not evoke harmful effects in the cornea or lens. [source] Photochemistry and Photocytotoxicity of Alkaloids from Goldenseal (Hydrastis canadensis L.) 3: Effect on Human Lens and Retinal Pigment Epithelial CellsPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2007Colin F. Chignell ABSTRACT The dried root or rhizome of Goldenseal (Hydrastis canadensis L.) contains several alkaloids including berberine, hydrastine, palmatine and lesser amounts of canadine and hydrastinine. Preparations derived from Goldenseal have been used to treat skin and eye ailments. Berberine, the major alkaloid in Goldenseal root powder, has been used in eye drops to treat trachoma, a disease characterized by keratoconjunctivitis. Berberine and palmatine are also present in extracts from Berberis amurensis Ruprecht (Berberidaceae) which are used to treat ocular disorders. We have previously shown that Goldenseal alkaloids are phototoxic to keratinocytes (Chem Res Toxicol. 14, 1529, 2001; ibid 19, 739, 2006) and now report their effect on human lens and retinal pigment epithelial cells. Human lens epithelial cells (HLE-B3) were severely damaged when incubated with berberine (25 ,M) and exposed to UVA (5 J cm,2). Under the same conditions, palmatine was less phototoxic and hydrastine, canadine and hydrastinine were inactive. Moderate protection against berberine phototoxicity was afforded by the antioxidants ascorbate (2 mM) and N -acetylcysteine (5 mM). When exposed to UVA (5 J cm,2) both berberine (10 ,M) and palmatine (10 ,M) caused mild DNA damage as determined by the alkaline comet assay which measures single strand breaks. Berberine and palmatine are the only Goldenseal alkaloids with appreciable absorption above 400 nm. Because light at wavelengths below 400 nm is cut off by the anterior portion of the adult human eye only berberine and palmatine were tested for phototoxicity to human retinal pigment epithelial (hRPE) cells. Although berberine did damage hRPE cells when irradiated with visible light (, > 400 nm) approximately 10 times higher concentrations were required to produce the same amount of damage as seen in lens cells. Palmatine was not phototoxic to hRPE cells. Neither berberine nor palmatine photodamaged DNA in hRPE. Infusions of Goldenseal are estimated to contain ,1 mM berberine, while in tinctures the alkaloid concentration may be more than 10 times higher. Our findings show that eyewashes and lotions derived from Goldenseal or containing berberine must be used with caution when the eyes are exposed to bright sunlight but that oral preparations are not likely to cause ocular phototoxicity. [source] Role of Xanthurenic Acid 8- O -,- d -Glucoside, a Novel Fluorophore that Accumulates in the Brunescent Human Eye Lens,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 3 2002Geetha Thiagarajan ABSTRACT We have been able to identify a blue fluorophore from the low-molecular weight soluble fraction of human adult nondiabetic brunescent cataract lenses as xanthurenic acid 8- O -,- d -glucoside (XA8OG) (excitation = 338 nm and emission = 440 nm). To determine the role of this fluorophore in the lens, we have examined its photophysical and photodynamic properties. We found XA8OG to have a fluorescence quantum yield (,) of 0.22 and a major emission lifetime of 12 ns. We found it to be a UVA-region sensitizer, capable of efficiently generating singlet oxygen species but little of superoxide. We also demonstrated that XA8OG oxidizes proteins when irradiated with UVA light, causing photodynamic covalent chemical damage to proteins. Its accumulation in the aging human lens (and the attendant decrease of its precursor O -,- d -glucoside of 3-hydroxykynurenine) can, thus, add to the oxidative burden on the system. XA8OG, thus, appears to be an endogenous chromophore in the lens, which can act as a cataractogenic agent. [source] Prison Drug Dealing and the Ethnographic LensTHE HOWARD JOURNAL OF CRIMINAL JUSTICE, Issue 4 2006BEN CREWE Having detailed the way that the research project proceeded, it analyses prison drug dealing as an individually meaningful act that takes place within a broader context of cultural codes, social relations and institutional policies. It suggests that, to unpack these issues fully, and chart the terms of the internal economy which heroin dominates, a committed attendance in the prison establishment, and an approach that is broad and exploratory, is of great benefit. [source] Savage and Sweet: The World Through the Shockumentary Film LensTHE JOURNAL OF POPULAR CULTURE, Issue 6 2007Robert G. Weiner No abstract is available for this article. [source] A re-assessment of the taxonomy of Lens Mill. (Leguminosae, Papilionoideae, Vicieae)BOTANICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2000MORAG E. FERGUSON Three taxonomic problems exist within the genus Lens. The first is the lark of agreement on classification and rank at the specific and sub-specific levels; the second involves the relationship between the recently distinguished L lamottei and L odemensis or L tomentosus and the third is the unreliability of stipule orientation as the primary character to distinguish between L odemensic and L. nigricans. The objectives of this study were to address these problems by investigating the classification of Lens in the light of evidence relating to crossability and phenetic relations, to idcntify morphological markers for taxon delimitation within the genus Lens., with special reference to L. lamottei, L nigricans and L odemensis, and to determine whether the taxon delimitation is supported by isozyme and RAPD evidence. As a result of these studies two new combinations are proposed, with L odemensis and I tamentosus being reduced to sub-species of L culinaris. A classification, key and descriptions of the accepted taxa within the genus are presented. [source] Powder on a Glass Lens, Courtesy of PhotoDisc, Inc./Getty Images (Chem. Eng.CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2009Technol. No abstract is available for this article. [source] 3425: Influence of cataract morphology on retinal straylight and straylight changes due to cataract surgery using the Morcher 89A Bag in the LensTMACTA OPHTHALMOLOGICA, Issue 2010MJ TASSIGNON Purpose To evaluate straylight and contrast sensitivity (CS) in eyes with various cataract morphologies, to determine which type of cataract presents a higher impairment of visual function with respect to proposed norms car driver safety and to compare retinal straylight and CS before and after implantation of a Morcher 89A IOL. Methods BCVA, CS and straylight were measured in 97 cataractous eyes using respectively a Snellen chart, a Pelli-Robson chart and the C-Quant. Cataracts were graded using the LOCS III scale and divided into four groups: nuclear, cortical, nuclear-cortical and posterior subcapsular cataract. These results were compared to data from 38 cataract-free control subjects. A separate group of 71 eyes had their straylight measured before and after cataract surgery. Results CS was reduced and straylight increased in all cataract patients, most notably in posterior subcapsular and nuclear-cortical cataract. CS and BCVA were correlated (r=0.44), whereas straylight and BCVA were not. Applying cut-off values as proposed by European drivers studies of l.25 log CS and 1.4 log straylight as safe margins for driving, 31% would be considered unfit to drive on the basis of CS and 78% on the basis of straylight although their visual acuity was still above the current European visual acuity requirement for driving. Retinal straylight reduced significantly from 1.560.26 to 1.250.22logunits (P<0.001) after IOL implantation . Conclusion Straylight and, to a lesser extent, CS are complementary to BCVA and should be taken into account when considering driving eligibility. After IOL implantation straylight reduces significantly, resulting in a significant increase in driving eligibility. [source] 2145: Descemet´s membrane detachment 16 years after PK and 10 months after phacoACTA OPHTHALMOLOGICA, Issue 2010JO FERNANDEZ MENDY Purpose The purpose of this paper is to present an unusual case of DMD and analyze this complication Methods A 57-year-old woman, who had bilateral keratoconus, underwent three penetrating keratoplasties (PK) on her RE in 1981, 1993 and 1995 resulting in ptisis bulbi. In her LE she underwent two PK (1981, 1994) follow by arcuate incisions (1995) and an uneventful phacoemulsification in 2007. 10 months after cataract surgery, she begun with blurred vision, the BCVA was 20/400 and was seen by 3 ophthalmologists who made the diagnosis of endothelial failure and suggested a new PK or a DSAEK. We performed an Optical Coherence Tomography, diagnosing a complete Descemet´s membrane detachment (DMD). An intracameral gas injection of C3F8 at 16% was performed in the operating room, and the patient was instructed to maintain a supine position. After 24 hours VA improved to 20/80 and after 72 hours 20/30 UCVA. A small bubble was present in the anterior chamber for more than 3 weeks. One month later she achieved 20/20 with Contact Lens. During the first year after reattachment it was necessary to change the CL due to an increasing with the rule astigmatism from 3D to 5D. Results Two years after gas injection BSVA is 20/25 because she is no longer using CL, Descemet´s membrane still remains well attached, even thought we realized that there was a trend to steepen the vertical meridian due to the widening of a nasal arcuate incision, that we think was the origin of the DMD. Conclusion DMD is a rare complication of Phacoemulsification, seen immediately after the surgery. So far there has not reported any complete DMD after phaco after PK. We think that it is mandatory to perform a corneal OCT in all cases of PK and stromal edema; it could probably be a DMD. [source] Visual function tests, eye disease and symptoms of visual disability: a population-based assessmentCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 1 2000Rebecca Q Ivers MPH ABSTRACT Purpose: To examine associations between eye disease and tests of visual function with self-reported visual disability. Methods: The Blue Mountains Eye Study is a cross-sectional census-based survey of eye disease in two postcode areas in the Blue Mountains, west of Sydney, Australia. Of 4433 eligible residents, 3654 (82.4%) participated. Subjects had a detailed eye examination, including tests of visual acuity, contrast sensitivity, disability glare and visual field. Lens and retinal photographs were taken and graded according to standardized protocols for presence of cataract, early and late age-related maculopathy, glaucoma, diabetic retinopathy, retinal vein occlusion and other eye diseases. An interviewer-administered questionnaire included questions about perception of visual disability. Results: Scores on all tests of visual function significantly decreased with age (P < 0.0001). This decrease persisted for all tests except disability glare after excluding subjects with identifiable eye disease. The presence of one or more eye diseases was significantly associated with all (self-reported) measures of visual disability (trouble driving at night, difficulty recognizing a friend across the street, reading a newspaper or recognizing detail on television); mixed cataract (cortical and nuclear, or posterior subcapsular and nuclear) was associated with trouble driving at night and difficulty recognizing a friend across the street. A 10-letter (two-line) decrease in best corrected or presenting visual acuity was significantly associated with all self-reported measures of visual disability, as was a two-step decrease in contrast sensitivity. A five-point increase in points missing in the visual field was weakly but significantly associated with all self-reported measures of visual disability except trouble driving at night. Conclusions: Visual function declines with age. Impaired visual function was strongly, and eye disease relatively weakly associated with reports of visual disability. [source] | ||||||||||||||||||||||||||||||||||||||||