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1.
Violence Against Women ; : 10778012241234895, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409964

RESUMO

After decades of work by feminists to criminalize domestic violence, more recently feminist abolitionists have identified the harm that the carceral state has on all impacted by it, including victims/survivors. Based on interviews with a diverse sample of 22 women and men who were system impacted, we find evidence of cases in which the criminal legal system both helped and harmed the victim/survivor. We identify policy interventions that promote alternative methods to intervening in intimate partner violence relationships that center the victim/survivor, create safety, and reduce the increased surveillance and overall impact of the criminal legal system.

2.
Doc Ophthalmol ; 147(1): 45-57, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36995437

RESUMO

PURPOSE: Exposure to blue light is thought to be harmful to the retina. The purpose of this study was to determine the effects of long-term exposure to narrowband blue light on retinal function in rhesus monkeys. METHODS: Young rhesus monkeys were reared under short-wavelength "blue" light (n = 7; 465 nm, 183 ± 28 lx) on a 12-h light/dark cycle starting at 26 ± 2 days of age. Age-matched control monkeys were reared under broadband "white" light (n = 8; 504 ± 168 lx). Light- and dark-adapted full-field flash electroretinograms (ERGs) were recorded at 330 ± 9 days of age. Photopic stimuli were brief red flashes (0.044-5.68 cd.s/m2) on a rod-saturating blue background and the International Society for Clinical Electrophysiology of Vision (ISCEV) standard 3.0 white flash on a 30 cd/m2 white background. Monkeys were dark adapted for 20 min and scotopic stimuli were ISCEV standard white flashes of 0.01, 3.0, and 10 cd.s/m2. A-wave, b-wave, and photopic negative response (PhNR) amplitudes were measured. Light-adapted ERGs in young monkeys were compared to ERGs in adult monkeys reared in white light (n = 10; 4.91 ± 0.88 years of age). RESULTS: For red flashes on a blue background, there were no significant differences in a-wave (P = 0.46), b-wave (P = 0.75), and PhNR amplitudes (P = 0.94) between white light and blue light reared monkeys for all stimulus energies. ISCEV standard light- and dark-adapted a- and b-wave amplitudes were not significantly different between groups (P > 0.05 for all). There were no significant differences in a- and b-wave implicit times between groups for all ISCEV standard stimuli (P > 0.05 for all). PhNR amplitudes of young monkeys were significantly smaller compared to adult monkeys for all stimulus energies (P < 0.05 for all). There were no significant differences in a-wave (P = 0.19) and b-wave (P = 0.17) amplitudes between young and adult white light reared monkeys. CONCLUSIONS: Long-term exposure to narrowband blue light did not affect photopic or scotopic ERG responses in young monkeys. Findings suggest that exposure to 12 h of daily blue light for approximately 10 months does not result in altered retinal function.


Assuntos
Visão de Cores , Eletrorretinografia , Animais , Macaca mulatta , Estimulação Luminosa , Retina
3.
Optom Vis Sci ; 100(1): 117-124, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542468

RESUMO

SIGNIFICANCE: As the myopia epidemic unfolds, there is growing urgency to identify and implement effective interventions to slow myopia progression. This investigation evaluated the effectiveness of an evidence-based myopia treatment algorithm in a clinical setting among 342 consecutive children. PURPOSE: This study aimed to evaluate effectiveness of a clinical treatment algorithm for myopia progression in children. METHODS: A retrospective cohort analysis was performed using data from myopic children treated for at least 1 year with a defined treatment algorithm incorporating orthokeratology, multifocal lenses, and atropine. The main outcome measures were the percentage of children experiencing ≤0.25 D of myopic cycloplegic spherical equivalent autorefraction (CSER) progression and ≤0.10 mm of axial elongation at 1, 2, and 3 years. The secondary outcome measures were the cumulative absolute reduction of axial elongation values derived from age- and ethnicity-matched virtual control data at 1, 2, and 3 years. RESULTS: Mean annual CSER change values (excluding orthokeratology) were -0.30, -0.20, and -0.13 D at 1, 2, and 3 years, respectively, with 59, 56, and 60% of patients demonstrating ≤0.25 D of change over the prior year. Mean annual axial elongation values were 0.13, 0.12, and 0.09 mm at 1, 2, and 3 years, respectively, with 52, 46, and 65% of patients demonstrating ≤0.10 mm of change over the prior year. The cumulative absolute reduction of axial elongation values were 0.11, 0.20, and 0.29 mm for 1, 2, and 3 years, respectively. CONCLUSIONS: The treatment algorithm demonstrated effective control of CSER and axial length in a diverse group of progressive myopic children, supporting its use for the clinical management of childhood myopia.


Assuntos
Miopia , Procedimentos Ortoceratológicos , Criança , Humanos , Estudos Retrospectivos , Miopia/diagnóstico , Miopia/epidemiologia , Miopia/terapia , Refração Ocular , Atropina/uso terapêutico , Midriáticos , Progressão da Doença , Comprimento Axial do Olho
4.
Exp Eye Res ; 217: 108937, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35074342

RESUMO

We investigated a commercial low-coherence interferometer (LenStar LS 900 optical biometer) in measuring young rhesus monkey ocular dimensions. Ocular biometry data obtained using a LenStar and an A-scan ultrasound instrument (OPT-scan 1000) from 163 rhesus monkeys during 20-348 days of age were compared by means of coefficients of concordance and 95% limits of agreement. Linear regression was employed to examine and analyze the inter-instrument discrepancies. In young rhesus monkeys, the test-retest reliability of the LenStar was equal to or exceeded that of A-scan ultrasound (intraclass correlation = 0.86 to 0.93). The inter-instrument agreement was strong for vitreous chamber depth and axial length (coefficient of concordance = 0.95 and 0.86, respectively) and moderate for anterior chamber depth and lens thickness (coefficient of concordance = 0.74 and 0.63, respectively). The LenStar systematically underestimated ocular dimensions when compared to A-scan ultrasound (mean magnitude of difference = 0.11-0.57 mm). This difference could be minimized using linear calibration functions to equate LenStar data with ultrasound data. When this method was applied, the values between instruments were in excellent absolute agreement (mean magnitude of difference = 0.004-0.01 mm). In conclusion, the LenStar reliably measured ocular dimensions in young monkeys. When an appropriate calibration function is applied, the LenStar can be used as a substitute for A-scan ultrasonography.


Assuntos
Biometria , Interferometria , Animais , Câmara Anterior/anatomia & histologia , Câmara Anterior/diagnóstico por imagem , Segmento Anterior do Olho , Comprimento Axial do Olho/anatomia & histologia , Córnea/diagnóstico por imagem , Interferometria/métodos , Macaca mulatta , Reprodutibilidade dos Testes , Ultrassonografia
6.
Front Physiol ; 12: 711525, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34393828

RESUMO

Purpose: Light affects a variety of non-image forming processes, such as circadian rhythm entrainment and the pupillary light reflex, which are mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs). The purpose of this study was to assess the effects of long- and short-wavelength ambient lighting on activity patterns and pupil responses in rhesus monkeys. Methods: Infant rhesus monkeys were reared under either broadband "white" light (n = 14), long-wavelength "red" light (n = 20; 630 nm), or short-wavelength "blue" light (n = 21; 465 nm) on a 12-h light/dark cycle starting at 24.1 ± 2.6 days of age. Activity was measured for the first 4 months of the experimental period using a Fitbit activity tracking device and quantified as average step counts during the daytime (lights-on) and nighttime (lights-off) periods. Pupil responses to 1 s red (651 nm) and blue (456 nm) stimuli were measured after approximately 8 months. Pupil metrics included maximum constriction and the 6 s post-illumination pupil response (PIPR). Results: Activity during the lights-on period increased with age during the first 10 weeks (p < 0.001 for all) and was not significantly different for monkeys reared in white, red, or blue light (p = 0.07). Activity during the 12-h lights-off period was significantly greater for monkeys reared in blue light compared to those in white light (p = 0.02), but not compared to those in red light (p = 0.08). However, blue light reared monkeys exhibited significantly lower activity compared to both white and red light reared monkeys during the first hour of the lights-off period (p = 0.01 for both) and greater activity during the final hour of the lights-off period (p < 0.001 for both). Maximum pupil constriction and the 6 s PIPR to 1 s red and blue stimuli were not significantly different between groups (p > 0.05 for all). Conclusion: Findings suggest that long-term exposure to 12-h narrowband blue light results in greater disruption in nighttime behavioral patterns compared to narrowband red light. Normal pupil responses measured later in the rearing period suggest that ipRGCs adapt after long-term exposure to narrowband lighting.

7.
Optom Vis Sci ; 98(5): 500-511, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33973918

RESUMO

SIGNIFICANCE: Planning for the effective delivery of eye care, on all levels, depends on an accurate and detailed knowledge of the optometric workforce and an understanding of demographic/behavioral trends to meet future needs of the public. PURPOSE: The purposes of this study were to assess the current and future supply of doctors of optometry and to examine in-depth trends related to (1) demographic shifts, (2) sex-based differences, (3) differences in practice behaviors in between self-employed and employed optometrists, and (4) the concept of additional capacity within the profession. METHODS: The 2017 National Optometry Workforce Survey (31 items) was distributed to 4050 optometrists, randomly sampled from a population of 45,033 currently licensed and practicing optometrists listed in the American Optometric Association's Optometry Master Data File. A stratified sampling method was applied to the population of optometrists using primary license state, age, and sex as variables to ensure a representative sample. RESULTS: With a response rate of 29% (1158 responses), the sample ensured a 95% confidence interval with a margin of error of <5%. Key results include finding no significant differences between men and women for hours worked (38.9 vs. 37.5), productivity (patient visits per hour, 2.0 vs. 1.9), or career options/professional growth satisfaction with 65% for both. The data indicate a likely range of additional patient capacity of 2.29 to 2.57 patients per week (5.05 to 5.65 million annually profession-wide). CONCLUSIONS: The optometric workforce for the next decade is projected to grow 0.6 to 0.7% more annually than the U.S. population. The study found additional capacity for the profession more limited than previously suggested. Findings also illustrate an evolving/equitable workforce based on sex, in terms of both productivity and satisfaction. The trend toward employed versus self-employed was marked with 44% reporting they are employed, up from 29% in 2012.


Assuntos
Necessidades e Demandas de Serviços de Saúde/estatística & dados numéricos , Mão de Obra em Saúde/estatística & dados numéricos , Optometristas/provisão & distribuição , Optometria/estatística & dados numéricos , Adulto , Idoso , Feminino , Pesquisa sobre Serviços de Saúde/estatística & dados numéricos , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Prática Profissional/estatística & dados numéricos , Inquéritos e Questionários , Estados Unidos
8.
Invest Ophthalmol Vis Sci ; 62(5): 6, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909032

RESUMO

The prevalence of myopia has markedly increased in East and Southeast Asia, and pathologic consequences of myopia, including myopic maculopathy and high myopia-associated optic neuropathy, are now some of the most common causes of irreversible blindness. Hence, strategies are warranted to reduce the prevalence of myopia and the progression to high myopia because this is the main modifiable risk factor for pathologic myopia. On the basis of published population-based and interventional studies, an important strategy to reduce the development of myopia is encouraging schoolchildren to spend more time outdoors. As compared with other measures, spending more time outdoors is the safest strategy and aligns with other existing health initiatives, such as obesity prevention, by promoting a healthier lifestyle for children and adolescents. Useful clinical measures to reduce or slow the progression of myopia include the daily application of low-dose atropine eye drops, in concentrations ranging between 0.01% and 0.05%, despite the side effects of a slightly reduced amplitude of accommodation, slight mydriasis, and risk of an allergic reaction; multifocal spectacle design; contact lenses that have power profiles that produce peripheral myopic defocus; and orthokeratology using corneal gas-permeable contact lenses that are designed to flatten the central cornea, leading to midperipheral steeping and peripheral myopic defocus, during overnight wear to eliminate daytime myopia. The risk-to-benefit ratio needs to be weighed up for the individual on the basis of their age, health, and lifestyle. The measures listed above are not mutually exclusive and are beginning to be examined in combination.


Assuntos
Acomodação Ocular/fisiologia , Lentes de Contato , Óculos , Miopia/prevenção & controle , Refração Ocular/fisiologia , Progressão da Doença , Saúde Global , Humanos , Miopia/epidemiologia , Miopia/fisiopatologia , Prevalência
9.
Invest Ophthalmol Vis Sci ; 62(5): 7, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909031

RESUMO

Purpose: The International Myopia Institute (IMI) Yearly Digest highlights new research considered to be of importance since the publication of the first series of IMI white papers. Methods: A literature search was conducted for articles on myopia between 2019 and mid-2020 to inform definitions and classifications, experimental models, genetics, interventions, clinical trials, and clinical management. Conference abstracts from key meetings in the same period were also considered. Results: One thousand articles on myopia have been published between 2019 and mid-2020. Key advances include the use of the definition of premyopia in studies currently under way to test interventions in myopia, new definitions in the field of pathologic myopia, the role of new pharmacologic treatments in experimental models such as intraocular pressure-lowering latanoprost, a large meta-analysis of refractive error identifying 336 new genetic loci, new clinical interventions such as the defocus incorporated multisegment spectacles and combination therapy with low-dose atropine and orthokeratology (OK), normative standards in refractive error, the ethical dilemma of a placebo control group when myopia control treatments are established, reporting the physical metric of myopia reduction versus a percentage reduction, comparison of the risk of pediatric OK wear with risk of vision impairment in myopia, the justification of preventing myopic and axial length increase versus quality of life, and future vision loss. Conclusions: Large amounts of research in myopia have been published since the IMI 2019 white papers were released. The yearly digest serves to highlight the latest research and advances in myopia.


Assuntos
Miopia/terapia , Procedimentos Ortoceratológicos/métodos , Qualidade de Vida , Refração Ocular/fisiologia , Progressão da Doença , Humanos , Miopia/classificação , Miopia/fisiopatologia
10.
Invest Ophthalmol Vis Sci ; 62(5): 1, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33909037

RESUMO

The International Myopia Institute's (IMI) mission is to advance research, education, and management of myopia to decrease future vision impairment and blindness associated with increasing myopia. Its approach is to bring together scientists, clinicians, policymakers, government members, and educators into the field of myopia to stimulate collaboration and sharing of knowledge. The latest reports are on pathologic myopia, the impact of myopia, risk factors for myopia, accommodation and binocular vision in myopia development and progression, and the prevention of myopia and its progression. Together with the digest updating the 2019 International Myopia Institute white papers using the research published in the last 18 months, these evidence-based consensus white papers help to clarify the imperative for myopia control and the role of environmental modification initiatives, informing an evidence-based clinical approach. This guidance includes who to treat and when to start or stop treatment, and the advantages and limitations of different management approaches.


Assuntos
Acomodação Ocular , Miopia/prevenção & controle , Procedimentos Ortoceratológicos/métodos , Visão Binocular/fisiologia , Congressos como Assunto , Humanos , Miopia/fisiopatologia
11.
Invest Ophthalmol Vis Sci ; 62(4): 27, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33891682

RESUMO

Purpose: Infantile strabismus impedes the development of stereopsis. In optically strabismic monkeys, 2 continuous hours of normal binocular vision per day has been shown to preserve near-normal stereopsis. In this study, we investigated whether, as in learning, multiple shorter periods of intervention would further boost performance. Methods: To simulate infantile esotropia, infant monkeys were reared with 30 prism diopters base-in starting at 4 weeks of age. Daily periods of normal binocular vision were provided by replacing prisms with plano lenses. Altogether, 14 monkeys were prism reared: 2 with continuous prism, 2 with 2 continuous hours of normal binocular vision per day, 6 with 2 noncontinuous hours, and 4 with 1 noncontinuous hour of binocular vision each day. Seven normally reared monkeys provided control data. Behavioral methods were employed to measure spatial contrast sensitivity, eye alignment, and stereopsis. Results: One monkey reared with continuous prism had poor stereopsis, and the other had no stereopsis. Ten of the 12 monkeys reared with periods of normal binocular vision had stereopsis, and those with longer and more continuous periods of binocular vision had stereopsis approaching that of normally reared monkeys. Conclusions: During early development, multiple short periods of binocular vision were effective in preserving clinically significant stereopsis in monkeys. These results suggest that by providing relatively short multiple daily intervention periods, stereopsis may be preserved in strabismic human children.


Assuntos
Ritmo Circadiano/fisiologia , Percepção de Profundidade/fisiologia , Estrabismo/fisiopatologia , Visão Binocular/fisiologia , Córtex Visual/fisiopatologia , Animais , Sensibilidades de Contraste/fisiologia , Modelos Animais de Doenças , Macaca mulatta
12.
Vision Res ; 183: 106-117, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33799131

RESUMO

Although reduced ambient lighting ("dim" light) can cause myopia in emmetropizing chicks, it does not necessarily lead to myopic changes in emmetropizing rhesus monkeys. Because myopia is rarely spontaneous, a question remained whether dim light would hasten the progression of visually induced myopia. To determine the effects of dim light on the development of and recovery from form-deprivation myopia (FDM), seven 3-week-old infant rhesus monkeys were reared under dim light (mean ± SD = 55 ± 9 lx) with monocular diffuser spectacles until ~154 days of age, then maintained in dim light with unrestricted vision until ~337 days of age to allow for recovery. Refractive errors, corneal powers, ocular axial dimensions and sub-foveal choroidal thicknesses were measured longitudinally and compared to those obtained from form-deprived monkeys reared under typical laboratory lighting (504 ± 168 lx). Five of the seven subjects developed FDMs that were similar to those observed among their normal-light-reared counterparts. The average degree of form-deprivation-induced myopic anisometropia did not differ significantly between dim-light subjects (-3.88 ± 3.26D) and normal-light subjects (-4.45 ± 3.75D). However, three of the five dim-light subjects that developed obvious FDM failed to exhibit any signs of recovery and the two monkeys that were isometropic at the end of the treatment period manifest abnormal refractive errors during the recovery period. All refractive changes were associated with alterations in vitreous chamber elongation rates. It appears that dim light is not a strong myopiagenic stimulus by itself, but it can impair the optical regulation of refractive development in primates.


Assuntos
Iluminação , Miopia , Animais , Córnea , Olho , Macaca mulatta , Miopia/etiologia , Refração Ocular , Privação Sensorial
13.
Exp Eye Res ; 203: 108438, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33428866

RESUMO

Oral administration of the adenosine receptor (ADOR) antagonist, 7-methylxanthine (7-MX), reduces both form-deprivation and lens-induced myopia in mammalian animal models. We investigated whether topically instilled caffeine, another non-selective ADOR antagonist, retards vision-induced axial elongation in monkeys. Beginning at 24 days of age, a 1.4% caffeine solution was instilled in both eyes of 14 rhesus monkeys twice each day until the age of 135 days. Concurrent with the caffeine regimen, the monkeys were fitted with helmets that held either -3 D (-3D/pl caffeine, n = 8) or +3 D spectacle lenses (+3D/pl caffeine, n = 6) in front of their lens-treated eyes and zero-powered lenses in front of their fellow-control eyes. Refractive errors and ocular dimensions were measured at baseline and periodically throughout the lens-rearing period. Control data were obtained from 8 vehicle-treated animals also reared with monocular -3 D spectacles (-3D/pl vehicle). In addition, historical comparison data were available for otherwise untreated lens-reared controls (-3D/pl controls, n = 20; +3D/pl controls, n = 9) and 41 normal monkeys. The vehicle controls and the untreated lens-reared controls consistently developed compensating axial anisometropias (-3D/pl vehicle = -1.44 ± 1.04 D; -3D/pl controls = -1.85 ± 1.20 D; +3D/pl controls = +1.92 ± 0.56 D). The caffeine regime did not interfere with hyperopic compensation in response to +3 D of anisometropia (+1.93 ± 0.82 D), however, it reduced the likelihood that animals would compensate for -3 D of anisometropia (+0.58 ± 1.82 D). The caffeine regimen also promoted hyperopic shifts in both the lens-treated and fellow-control eyes; 26 of the 28 caffeine-treated eyes became more hyperopic than the median normal monkey (mean (±SD) relative hyperopia = +2.27 ± 1.65 D; range = +0.31 to +6.37 D). The effects of topical caffeine on refractive development, which were qualitatively similar to those produced by oral administration of 7-MX, indicate that ADOR antagonists have potential in treatment strategies for preventing and/or reducing myopia progression.


Assuntos
Comprimento Axial do Olho/efeitos dos fármacos , Cafeína/administração & dosagem , Emetropia/fisiologia , Miopia/prevenção & controle , Antagonistas de Receptores Purinérgicos P1/administração & dosagem , Administração Oftálmica , Animais , Animais Recém-Nascidos , Biometria , Óculos , Macaca mulatta , Miopia/fisiopatologia , Refração Ocular/fisiologia
14.
J Addict Med ; 15(3): 181-186, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32833748

RESUMO

BACKGROUND: In 2017, approximately 11.4 million Americans used opioids inappropriately. Nearly 47,600 deaths in 2017 were attributable to overdose on opioids. Intranasal naloxone was approved by the Food and Drug Administration in 2015 as a rescue medication for opioid overdose. New York State launched a prescription drug monitoring program in 2012, the Internet System for Tracking Over-Prescribing (I-STOP), that required completion before dispensing any controlled substance. Currently, prescribing naloxone at our institution requires 10 clicks and 2 free text boxes. The goal of this project was to increase the prescribing of intranasal naloxone by utilizing EMR automation and visualization tools. METHODS: Our intervention embedded a section within the required I-STOP note, displaying the last date naloxone was prescribed and an option to "prescribe intranasal naloxone." If checked, a prepopulated order dialog box was generated. RESULTS: Intranasal naloxone orders for the institution totaled 65 for 2 months before the intervention and 203 for 2 months after the intervention, with 112 (55%) coming directly from the I-STOP note modification. Ease of prescribing improved as total clicks were reduced from 10 to 2, and free text boxes from 2 to 0. CONCLUSIONS: Our findings suggest that a clinical decision support system can be an effective way to increase hospital-wide naloxone prescribing rates. We were able to increase prescribing rates by more than three-fold, significantly increasing the availability of a rescue medication to individuals at high-risk for overdose. Intranasal naloxone prescribing increased with the implementation of a visual reminder and a more intuitive ordering experience while preserving provider autonomy.


Assuntos
Overdose de Drogas , Naloxona , Administração Intranasal , Analgésicos Opioides/uso terapêutico , Automação , Overdose de Drogas/tratamento farmacológico , Humanos , Naloxona/uso terapêutico , Antagonistas de Entorpecentes/uso terapêutico
15.
Vision Res ; 176: 48-59, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32777589

RESUMO

Studies in chickens suggest low intensity ambient lighting causes myopia. The purpose of this experiment was to examine the effects of low intensity ambient lighting (dim light) on normal refractive development in macaque monkeys. Seven infant rhesus monkeys were reared under dim light (room illumination level: ~55 lx) from 24 to ~310 days of age with otherwise unrestricted vision. Refractive error, corneal power, ocular axial dimensions, and choroidal thickness were measured in anesthetized animals at the onset of the experiment and periodically throughout the dim-light-rearing period, and were compared with those of normal-light-reared monkeys. We found that dim light did not produce myopia; instead, dim-light monkeys were hyperopic relative to normal-light monkeys (median refractive errors at ~155 days, OD: +3.13 D vs. +2.31 D; OS: +3.31D vs. +2.44 D; at ~310 days, OD: +2.75D vs. +1.78D, OS: +3.00D vs. +1.75D). In addition, dim-light rearing caused sustained thickening in the choroid, but it did not alter corneal power development, nor did it change the axial nature of the refractive errors. These results showed that, for rhesus monkeys and possibly other primates, low ambient lighting by itself is not necessarily myopiagenic, but might compromise the efficiency of emmetropization.


Assuntos
Hiperopia , Iluminação , Animais , Animais Recém-Nascidos , Galinhas , Córnea , Olho , Macaca mulatta , Refração Ocular
16.
J Neurosci ; 39(29): 5673-5684, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31147523

RESUMO

Encoding of visual information requires precisely timed spiking activity in the network of cortical neurons; irregular spiking can interfere with information processing especially for low-contrast images. The vision of newborn infants is impoverished. An infant's contrast sensitivity is low and the ability to discriminate complex stimuli is poor. The neural mechanisms that limit the visual capacities of infants are a matter of debate. Here we asked whether noisy spiking and/or crude information processing in visual cortex limit infant vision. Since neurons beyond the primary visual cortex (V1) have rarely been studied in neonates or infants, we focused on the firing pattern of neurons in visual area V2, the earliest extrastriate visual area of both male and female macaque monkeys (Maccaca mulatta). For eight stimulus contrasts ranging from 0% to 80%, we analyzed spiking irregularity by calculating the square of the coefficient of variation (CV2) in interspike intervals, the trial-to-trial fluctuation in spiking (Fano factor), and the amount of information on contrast conveyed by each spiking (information density). While the contrast sensitivity of infant neurons was reduced as expected, spiking noise, both the magnitude of spiking irregularity and the trial-to-trial fluctuations, was much lower in the spike trains of infant V2 neurons compared with those of adults. However, information density for V2 neurons was significantly lower in infants. Our results suggest that poor contrast sensitivity combined with lower information density of extrastriate neurons, despite their lower spiking noise, may limit behaviorally determined contrast sensitivity soon after birth.SIGNIFICANCE STATEMENT Despite >50 years of investigations on the postnatal development of the primary visual cortex (V1), cortical mechanisms that may limit infant vision are still unclear. We investigated the quality and strength of neuronal firing in primate visual area V2 by analyzing contrast sensitivity, spiking variability, and the amount of information on contrast conveyed by each action potential (information density). Here we demonstrate that the firing rate, contrast sensitivity, and dynamic range of V2 neurons were depressed in infants compared with adults. Although spiking noise was less, information density was lower in infant V2. Impoverished neuronal drive and lower information density in extrastriate visual areas, despite lower spiking noise, largely explain the impoverished visual sensitivity of primates near birth.


Assuntos
Potenciais de Ação/fisiologia , Neurônios/fisiologia , Córtex Visual/citologia , Córtex Visual/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Feminino , Macaca mulatta , Estimulação Luminosa/métodos
17.
Ophthalmic Physiol Opt ; 39(4): 294-307, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31180155

RESUMO

PURPOSE: We aimed to determine myopia control efficacy with novel contact lenses (CL) that (1) reduced both central and peripheral defocus, and (2) provided extended depth of focus with better global retinal image quality for points on, and anterior to, the retina and degraded for points posterior to the retina. METHODS: Children (n = 508, 8-13 years) with cycloplegic spherical equivalent (SE) -0.75 to -3.50D were enrolled in a prospective, double blind trial and randomised to one of five groups: (1) single vision, silicone hydrogel (SH) CL; (2) two groups wearing SH CL that imposed myopic defocus across peripheral and central retina (test CL I and II; +1.00D centrally and +2.50 and +1.50 for CL I and II at 3 mm semi-chord respectively); and (3) two groups wearing extended depth of focus (EDOF) hydrogel CL incorporating higher order aberrations to modulate retinal image quality (test CL III and IV; extended depth of focus of up to +1.75D and +2.50D respectively). Cycloplegic autorefraction and axial length (AL) measurements were conducted at six monthly intervals. Compliance to lens wear was assessed with a diary and collected at each visit. Additionally, subjective responses to various aspects of lens wear were assessed. The trial commenced in February 2014 and was terminated in January 2017 due to site closure. Myopia progression over time between groups was compared using linear mixed models and where needed post hoc analysis with Bonferroni corrections conducted. RESULTS: Myopia progressed with control CL -1.12 ± 0.51D/0.58 ± 0.27 mm for SE/AL at 24 months. In comparison, all test CL had reduced progression with SE/AL ranging from -0.78D to -0.87D/0.41-0.46 mm at 24 months (AL: p < 0.05 for all test CL; SE p < 0.05 for test CL III and IV) and represented a reduction in axial length elongation of about 22% to 32% and reduction in spherical equivalent of 24% to 32%. With test CL, a greater slowing ranging from 26% to 43% was observed in compliant wearers (≥6 days per week; Control CL: -0.64D/0.30 mm and -1.14D/0.58 mm vs test CL: -0.42D to -0.47D/0.12-0.18 mm and -0.70 to -0.81D/0.19-0.25 mm at 12 and 24 months respectively). CONCLUSIONS: Contact lenses that either imposed myopic defocus at the retina or modulated retinal image quality resulted in a slower progression of myopia with greater efficacy seen in compliant wearers. Importantly, there was no difference in the myopia control provided by either of these strategies.


Assuntos
Lentes de Contato Hidrofílicas , Miopia Degenerativa/terapia , Adolescente , Análise de Variância , Criança , Método Duplo-Cego , Feminino , Humanos , Masculino , Miopia Degenerativa/prevenção & controle , Estudos Prospectivos , Desenho de Prótese
19.
Invest Ophthalmol Vis Sci ; 60(3): M1-M19, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30817825

RESUMO

With the growing prevalence of myopia, already at epidemic levels in some countries, there is an urgent need for new management approaches. However, with the increasing number of research publications on the topic of myopia control, there is also a clear necessity for agreement and guidance on key issues, including on how myopia should be defined and how interventions, validated by well-conducted clinical trials, should be appropriately and ethically applied. The International Myopia Institute (IMI) reports the critical review and synthesis of the research evidence to date, from animal models, genetics, clinical studies, and randomized controlled trials, by more than 85 multidisciplinary experts in the field, as the basis for the recommendations contained therein. As background to the need for myopia control, the risk factors for myopia onset and progression are reviewed. The seven generated reports are summarized: (1) Defining and Classifying Myopia, (2) Experimental Models of Emmetropization and Myopia, (3) Myopia Genetics, (4) Interventions for Myopia Onset and Progression, (5) Clinical Myopia Control Trials and Instrumentation, (6) Industry Guidelines and Ethical Considerations for Myopia Control, and (7) Clinical Myopia Management Guidelines.


Assuntos
Miopia/prevenção & controle , Transtornos da Visão/prevenção & controle , Animais , Progressão da Doença , Humanos , Internacionalidade , Miopia/classificação , Miopia/epidemiologia , Prevalência , Fatores de Risco
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