Is pupil diameter influenced by refractive error?

Purpose: To investigate the relationship between pupil diameter and refractive error and how refractive correction, target luminance, and accommodation modulate this relationship. Methods: Sixty emmetropic, myopic, and hyperopic subjects (age range, 18 to 35 years) viewed an illuminated target (luminance: 10, 100, 200, 400, 1000, 2000, and 4100 cd/m2) within a Badal optical system, at 0 diopters (D) and −3 D vergence, with and without refractive correction. Refractive error was corrected using daily disposable contact lenses. Pupil diameter and accommodation were recorded continuously using a commercially available photorefractor. Results: No significant difference in pupil diameter was found between the refractive groups at 0 D or −3 D target vergence, in the corrected or uncorrected conditions. As expected, pupil diameter decreased with increasing luminance. Target vergence had no significant influence on pupil diameter. In the corrected condition, at 0 D target vergence, the accommodation response was similar in all refractive groups. At −3 D target vergence, the emmetropic and myopic groups accommodated significantly more than the hyperopic group at all luminance levels. There was no correlation between accommodation response and pupil diameter or refractive error in any refractive group. In the uncorrected condition, the accommodation response was significantly greater in the hyperopic group than in the myopic group at all luminance levels, particularly for near viewing. In the hyperopic group, the accommodation response was significantly correlated with refractive error but not pupil diameter. In the myopic group, accommodation response level was not correlated with refractive error or pupil diameter. Conclusions: Refractive error has no influence on pupil diameter, irrespective of refractive correction or accommodative demand. This suggests that the pupil is controlled by the pupillary light reflex and is not driven by retinal blur.

Randomized crossover trial of silicone hydrogel presbyopic contact lenses

PURPOSE: To assess the performance of four commercially available silicone hydrogel multifocal monthly contact lens designs against monovision. METHODS: A double-masked randomized crossover trial of Air Optix Aqua multifocal, PureVision 2 for Presbyopia, Acuvue OASYS for Presbyopia, Biofinity multifocal, and monovision with Biofinity contact lenses was conducted on 35 presbyopes (54.3 ± 6.2 years). After 4 weeks of wear, visual performance was quantified by high- and low-contrast visual acuity under photopic and mesopic conditions, reading speed, defocus curves, stereopsis, halometry, aberrometry, Near Activity Visual Questionnaire rating, and subjective quality of vision scoring. Bulbar, limbal, and palpebral hyperemia and corneal staining were graded to monitor the impact of each contact lens on ocular physiology. RESULTS: High-contrast photopic visual acuity (p = 0.102), reading speed (F = 1.082, p = 0.368), and aberrometry (F = 0.855, p = 0.493) were not significantly different between presbyopic lens options. Defocus curve profiles (p <0.001), stereopsis (p <0.001), halometry (F = 4.101, p = 0.004), Near Activity Visual Questionnaire (F = 3.730, p = 0.007), quality of vision (p = 0.002), bulbar hyperemia (p = 0.020), and palpebral hyperemia (p = 0.012) differed significantly between lens types, with the Biofinity multifocal lens design principal (center-distance lens was fitted to the dominant eye and a center-near lens to the nondominant eye) typically outperforming the other lenses. CONCLUSIONS: Although ocular aberration variation between individuals largely masks the differences in optics between current multifocal contact lens designs, certain design strategies can outperform monovision, even in early presbyopes.

Eye movement analysis in congenital nystagmus:concise parameters estimation

Along with other diseases that can affect binocular vision, reducing the visual quality of a subject, Congenital Nystagmus (CN) is of peculiar interest. CN is an ocular-motor disorder characterized by involuntary, conjugated ocular oscillations and, while identified more than forty years ago, its pathogenesis is still under investigation. This kind of nystagmus is termed congenital (or infantile) since it could be present at birth or it can arise in the first months of life. The majority of CN patients show a considerable decrease of their visual acuity: image fixation on the retina is disturbed by nystagmus continuous oscillations, mainly horizontal. However, the image of a given target can still be stable during short periods in which eye velocity slows down while the target image is placed onto the fovea (called foveation intervals). To quantify the extent of nystagmus, eye movement recordings are routinely employed, allowing physicians to extract and analyze nystagmus main features such as waveform shape, amplitude and frequency. Use of eye movement recording, opportunely processed, allows computing "estimated visual acuity" predictors, which are analytical functions that estimate expected visual acuity using signal features such as foveation time and foveation position variability. Hence, it is fundamental to develop robust and accurate methods to measure both those parameters in order to obtain reliable values from the predictors. In this chapter the current methods to record eye movements in subjects with congenital nystagmus will be discussed and the present techniques to accurately compute foveation time and eye position will be presented. This study aims to disclose new methodologies in congenital nystagmus eye movements analysis, in order to identify nystagmus cycles and to evaluate foveation time, reducing the influence of repositioning saccades and data noise on the critical parameters of the estimation functions. Use of those functions extends the information acquired with typical visual acuity measurement (e.g., Landolt C test) and could be a support for treatment planning or therapy monitoring. © 2010 by Nova Science Publishers, Inc. All rights reserved.

Comparison of two formulas used to calculate summarized retinal vessel calibers

PURPOSE: To compare the Parr-Hubbard and Knudtson formulas to calculate retinal vessel calibers and to examine the effect of omitting vessels on the overall result. METHODS: We calculated the central retinal arterial equivalent (CRAE) and central retinal venular equivalent (CRVE) according to the formulas described by Parr-Hubbard and Knudtson including the six largest retinal arterioles and venules crossing through a concentric ring segment (measurement zone) around the optic nerve head. Once calculated, we removed one arbitrarily selected artery and one arbitrarily selected vein and recalculated all outcome parameters again for (1) omitting one artery only, (2) omitting one vein only, and (3) omitting one artery and one vein. All parameters were compared against each other. RESULTS: Both methods showed good correlation (r for CRAE = 0.58; r for CRVE = 0.84), but absolute values for CRAE and CRVE were significantly different from each other when comparing both methods (p < 0.000001): CRAE had higher values for the Parr-Hubbard (165 [±16] μm) method compared with the Knudtson method (148 [±15] μm). In addition, CRAE and CRVE values dropped for both methods when omitting one arbitrarily selected vessel each (all p < 0.000001). Arteriovenous ratio (AVR) calculations showed a similar change for both methods when omitting one vessel each: AVR decreased when omitting one arteriole whereas it increased when omitting one venule. No change, however, was observed for AVR calculated with six or five vessel pairs each. CONCLUSIONS: Although the absolute value for CRAE and CRVE is changing significantly depending on the number of vessels included, AVR appears to be comparable as long as the same number of arterioles and venules is included.

Overview of risk factors for age-related macular degeneration

Age related macular degeneration (AMD) is the leading cause of blindness in individuals older than 65 years of age. It is a multifactorial disorder and identification of risk factors enables individuals to make life style choices that may reduce the risk of disease. This review discusses the role of genetics, sunlight, diet, cardiovascular factors, smoking, and alcohol as possible risk factors for AMD. Genetics plays a more significant role in AMD than previously thought, especially in younger patients, histocompatibility locus antigen (HLA) and complement system genes being the most significant. Whether the risk of AMD is increased by exposure to sunlight, cardiovascular risk factors, and diet is more controversial. Smoking is the risk factor most consistently associated with AMD. Current smokers are exposed to a two to three times higher risk of AMD than non-smokers and the risk increases with intensity of smoking. Moderate alcohol consumption is unlikely to increase the risk of AMD. Optometrists as front-line informers and educators of ocular health play a significant role in increasing public awareness of the risks of AMD. Cessation of smoking, the use of eye protection in high light conditions, dietary changes, and regular use of dietary supplements should all be considered to reduce the lifetime risk of AMD.

Crossover evaluation of silicone hydrogel daily disposable contact lenses

PURPOSE: To assess the surface tear breakup time and clinical performance of three daily disposable silicone hydrogel contact lenses over 16 hours of wear. METHODS: Thirty-nine patients (mean [±SD] age, 22.1 [±3.5] years) bilaterally wore (narafilcon A, filcon II-3, and delefilcon A) contact lenses in a prospective, randomized, masked, 1-week crossover clinical trial. Tear film was assessed by the tear meniscus height (TMH), ocular/contact lens surface temperature dynamics, and lens surface noninvasive breakup time at 8, 12, and 16 hours of wear. Clinical performance and ocular physiology were assessed by subjective questionnaire, by high-/low-contrast logMAR (logarithm of the minimum angle of resolution) acuity, and through bulbar and limbal hyperemia grading. Corneal and conjunctival staining were assessed after lens removal. RESULTS: Delefilcon A demonstrated a longer noninvasive breakup time (13.4 [±4.4] seconds) than filcon II-3 (11.6 [±3.7] seconds; p < 0.001) and narafilcon A (12.3 [±3.7] seconds; p < 0.001). A greater TMH (0.35 [±0.11] mm) was shown by delefilcon A than filcon II-3 (0.32 [±0.10] seconds; p = 0.016). Delefilcon A showed less corneal staining after 16 hours of lens wear (0.7 [±0.6] Efron grade) than filcon II-3 (1.1 [±0.7]; p < 0.001) and narafilcon A (0.9 [±0.7]; p = 0.031). Time was not a significant factor for prelens tear film stability (F = 0.594, p = 0.555) or TMH (F = 0.632, p = 0.534). Lens brand did not affect temperature (F = 1.220, p = 0.308), but it decreased toward the end of the day (F = 19.497, p < 0.001). Comfort, quality of vision, visual acuity and contrast acuity, and limbal grading were similar between the lens brands but decreased with time during the day (p < 0.05). CONCLUSIONS: The tear breakup time over the contact lens surface differed between lens types and may have a role in protecting the ocular surface.

Clinical evaluation of the Shin-Nippon SRW-5000 autorefractor in adults:an update

Purpose: The Shin-Nippon SRW-5000 is an open view autorefractor that superseded the Canon R-1 autorefractor in the mid-1990s and has been used widely in optometry and vision science laboratories. It has been used to measure refractive error, accommodation responses both statically and dynamically, off-axis refractive error, and adapted to measure pupil size. This paper presents an overview of the original 2001 clinical evaluation of the SRW-5000 in adults (Mallen et al., Ophthal Physiol Opt 2001; 21: 101) and provides an update on the use and modification of the instrument since the original publication. Recent findings: The SRW-5000 instrument, and the family of devices which followed, have shown excellent validity, repeatability, and utility in clinical and research settings. The instruments have also shown great potential for increased research functionality following a number of modifications. Summary: The SRW-5000 and its derivatives have been, and continue to be, of significant importance in our drive to understand myopia progression, myopia control techniques, and oculomotor function in human vision.

Overview of risk factors for age-related macular degeneration (AMD)

Age related macular degeneration (AMD) is the leading cause of blindness in individuals older than 65 years of age. It is a multifactorial disorder and identification of risk factors enables individuals to make life style choices that may reduce the risk of disease. This review discusses the role of genetics, sunlight, diet, cardiovascular factors, smoking, and alcohol as possible risk factors for AMD. Genetics plays a more significant role in AMD than previously thought, especially in younger patients, histocompatibility locus antigen (HLA) and complement system genes being the most significant. Whether the risk of AMD is increased by exposure to sunlight, cardiovascular risk factors, and diet is more controversial. Smoking is the risk factor most consistently associated with AMD. Current smokers are exposed to a two to three times higher risk of AMD than non-smokers and the risk increases with intensity of smoking. Moderate alcohol consumption is unlikely to increase the risk of AMD. Optometrists as front-line informers and educators of ocular health play a significant role in increasing public awareness of the risks of AMD. Cessation of smoking, the use of eye protection in high light conditions, dietary changes, and regular use of dietary supplements should all be considered to reduce the lifetime risk of AMD.

Robust tensor analysis with L1-norm

Tensor analysis plays an important role in modern image and vision computing problems. Most of the existing tensor analysis approaches are based on the Frobenius norm, which makes them sensitive to outliers. In this paper, we propose L1-norm-based tensor analysis (TPCA-L1), which is robust to outliers. Experimental results upon face and other datasets demonstrate the advantages of the proposed approach. © 2006 IEEE.

Pathology of the superior colliculus in chronic traumatic encephalopathy

PURPOSE: To investigate neuropathological changes in the superior colliculus in chronic traumatic encephalopathy. METHODS: The densities of the tau-immunoreactive neurofibrillary tangles, neuropil threads, dot-like grains, astrocytic tangles, and neuritic plaques, together with abnormally enlarged neurons, typical neurons, vacuolation, and frequency of contacts with blood vessels, were studied across the superior colliculus from pia mater to the periaqueductal gray in eight chronic traumatic encephalopathy and six control cases. RESULTS: Tau-immunoreactive pathology was absent in the superior colliculus of controls but present in varying degrees in all chronic traumatic encephalopathy cases, significant densities of tau-immunoreactive neurofibrillary tangles, NT, or dot-like grains being present in three cases. No significant differences in overall density of the tau-immunoreactive neurofibrillary tangles, neuropil threads, dot-like grains, enlarged neurons, vacuoles, or contacts with blood vessels were observed in control and chronic traumatic encephalopathy cases, but chronic traumatic encephalopathy cases had significantly lower mean densities of neurons. The distribution of surviving neurons across the superior colliculus suggested greater neuronal loss in intermediate and lower laminae in chronic traumatic encephalopathy. Changes in density of the tau-immunoreactive pathology across the laminae were variable, but in six chronic traumatic encephalopathy cases, densities of tau-immunoreactive neurofibrillary tangles, neuropil threads, or dot-like grains were significantly greater in intermediate and lower laminae. Pathological changes were not correlated with the distribution of blood vessels. CONCLUSIONS: The data suggest significant pathology affecting the superior colliculus in a proportion of chronic traumatic encephalopathy cases with a laminar distribution which could compromise motor function rather than sensory analysis.

Institutional Self study for the Liaison Committee on Medical Education

Draft of the College of Medicine's Institutional Self-Study for the LCME. Includes an overview of the College of Medicine's history, development, and vision, as well as details regarding the organization of the college, educational programs and resources, and future goals.

A atenção à crise e o apoio matricial: analisadores da estratégia atenção psicossocial

The National Policy on Mental Health is characterized as a territorial - political community , and it has the Psychoso cial Care Strategy (Eaps) as guideline for the proposal and the development of their actions. In its design, CAPS is idealized to be a strategic equipment within the Psychoso cial Care Network/RAPS. Matricial support and at tention to the crisis constitute strategic areas of action of CAPS in its replacement mission , and as it is g uided by the scope of deinstitutionalization, those are essential to the success of these services. We argue that sustain crises in existential territories of life is a condition for the effectiveness of psychosocial care and, ultimately, to the sustainability of its Reform. In this direction, the matricial support tool reveals a territorial supporter, intercessory and powerful in building a psychosocial care to the crisis. Recognized as one of the major challenges by the Brazilian Ministry of Health, forward these fronts materializes for workers in their mi cropolitical crafts. Our research arises as an investment toward empower them , and aimed to understand the operationalization of attention to the crisis and matricial support in a CAPS II, in the view of its workers . Besides, it aims to examine such practi ces forward the principles and purposes of Psychosocial Care Strategy. Inspired by the research - intervention and by the political and social ideas of Institutiona l Analysis, we offer a space for reflection and exchange, by implicational interviews , enablin g workers to launch them in analysis of practices in the EAPs view. We have done a documentary consulting CAPS Technical Project, and a return stage to the institution, by organizing workshop and conversation groups with CAPS workers. The results have show n that there are institutional logics in competition on that service. When operating the logic risk, some difficulties in sustaining most intense crisis situations were identified, the psychiatric hospital internment is used as a facility, particularly in view of some cases, in which the aggressiveness of the person in crises becomes aggressive, and when the brackets SAMU, the CAPS III and Comprehensive Care Beds do not respond satisfactorily to their users requests. Order weaknesses were indicated in this thesis as macropolitical and micropolitical interfering in network support. The matricial actions were identified as a powerful intercessor resource in crisis care appeared weakened, and indicates little porosity in the relationship between the Service and the territory where it takes place. Noticed by the logic of home care, without operate primarily as a knowledge exchange device, we saw capture points in the logic of assistance with ambulatoriza tion production of CAPS, welfare practices and "ext empore " . T he E APs , although it emerge s as a guiding, it is not seen to workers as effective practice. On the one hand, the results signaled that the attention to the crisis and the matricial actions are developed without tenacious connection with the purposes of EA Ps, on the other hand, successful cases were indicated with the main leads to conducting wire of intersectoral actions to the powerful bonds and to the participation of user in their care process es , indicating insurgent forces tha t intend by traditional lo gic .

Merleau-Ponty: uma ontologia do visível

This work discusses the ontology of the visible at the thought of Maurice Merleau-Ponty (1908-1961), which points to a depth and opacity of the perceived world that oppose transparency of geometric world thought by René Descartes (1596-1650). At first we approached the Cartesian discourse developed in Dioptrics Descartes, the first of three scientific discourses published in 1637, being introduced by the famous Discourse method. In this sense, this research discusses the mechanistic explanation that the modern philosopher has the vision, process comprising the formation of images on the retina and its communication to the brain, and the subsequent reading performed by an immaterial mind. Discusses the notion of image as a result of the interpretation of the spirit because, for Descartes, is not the eye that sees, but the spirit that reads and decodes the signals that the body receives the world. At another point, reflected on the criticism of the philosopher Maurice Merleau-Ponty at the thought of overflight present in Dioptrics Descartes. Therefore, it takes as its reference the third part of the book The Eye and the Spirit (1961), in which the intellectualist approach of vision is considered a failed attempt to move away from the visible to rebuild it from anywhere . In this sense, it reflects on a new ontology proposed by Merleau-Ponty thinking being without departing from the puzzles of the body and vision. Puzzles that show a promiscuity between the seer and the seen, between sentient and sensitive. Thus, this paper discusses how visibility was treated by the contemporary philosopher, not as something to be judged by the spirit to get a real nature of things, but as a manifestation of the same things. Finally, this research explores the ontology of the visible in merleaupontiano thought, an ontology that does not rebuild or appropriates visible by a thought of overflight, but what you do from your own visibility as compared original and constant with depth in the world.

Merleau-Ponty: uma ontologia do visível

This work discusses the ontology of the visible at the thought of Maurice Merleau-Ponty (1908-1961), which points to a depth and opacity of the perceived world that oppose transparency of geometric world thought by René Descartes (1596-1650). At first we approached the Cartesian discourse developed in Dioptrics Descartes, the first of three scientific discourses published in 1637, being introduced by the famous Discourse method. In this sense, this research discusses the mechanistic explanation that the modern philosopher has the vision, process comprising the formation of images on the retina and its communication to the brain, and the subsequent reading performed by an immaterial mind. Discusses the notion of image as a result of the interpretation of the spirit because, for Descartes, is not the eye that sees, but the spirit that reads and decodes the signals that the body receives the world. At another point, reflected on the criticism of the philosopher Maurice Merleau-Ponty at the thought of overflight present in Dioptrics Descartes. Therefore, it takes as its reference the third part of the book The Eye and the Spirit (1961), in which the intellectualist approach of vision is considered a failed attempt to move away from the visible to rebuild it from anywhere . In this sense, it reflects on a new ontology proposed by Merleau-Ponty thinking being without departing from the puzzles of the body and vision. Puzzles that show a promiscuity between the seer and the seen, between sentient and sensitive. Thus, this paper discusses how visibility was treated by the contemporary philosopher, not as something to be judged by the spirit to get a real nature of things, but as a manifestation of the same things. Finally, this research explores the ontology of the visible in merleaupontiano thought, an ontology that does not rebuild or appropriates visible by a thought of overflight, but what you do from your own visibility as compared original and constant with depth in the world.

DESENVOLVIMENTO E JUSTIÇA NA MISSÃO INTEGRAL: UMA ANÁLISE CRÍTICA DA PRESENÇA DA TEOLOGIA E PRÁXIS DA MISSÃO INTEGRAL NO SOLO PAULISTANO - Estudo da PIBSP.

No presente estudo sobre o tema: “Desenvolvimento e Justiça na Missão Integral: Uma análise crítica da presença da Teologia e Práxis da Missão Integral no Solo Paulistano” procura-se analisar a presença do conceito de desenvolvimento e justiça da Missão Integral no solo paulistano. Para tal análise tomou-se como sujeito de pesquisa a Primeira Igreja Batista de São Paulo. Esta dissertação foi desenvolvida no Programa de Pós- Graduação em Ciências da Religião, e pertence à linha de pesquisa “Religião, Sociedade e Cultura”. A metodologia adotada na coleta de dados foi de uma revisão bibliográfica e pesquisa de campo por meio de um roteiro de entrevista. Os questionamentos que nortearam a pesquisa foram: O que é desenvolvimento e Justiça na Missão Integral? É possível notar a presença desses conceitos na práxis e na teologia da Primeira Igreja Batista de São Paulo? Após uma análise da Missão Integral e da Igreja pesquisada, foi possível verificar as aproximações e distanciamentos, assim como hipóteses que justificassem esses fatos. No primeiro capítulo foi apresentada a Missão Integral, sua história, teologia e método. No segundo capítulo os conceitos de desenvolvimento e justiça foram trabalhados. O último capítulo apresentou a Primeira Igreja Batista de São Paulo; buscou estabelecer diálogo entre o conceito de Desenvolvimento e Justiça da Missão Integral e a teologia e práxis da Primeira Igreja Batista de São Paulo.