Factors That Influence the Receipt of Eye Care

PubMed Central

Alexander, Robert L.; Miller, Nancy A.; Cotch, Mary Frances; Janiszewski, Rosemary

2010-01-01

Objectives To better understand what factors influence the receipt of eye care so that screening and education programs can be designed to promote early detection and treatment. Methods Twenty focus groups were conducted. Analyses entailed debriefing sessions, coding, and interpreting transcribed data. Results Attitudes about eyesight and eye exams influence the receipt of preventive eye care. Limited knowledge about certain eye diseases and conditions was reported. Participants stated that their primary care providers did not communicate information with them about eyesight nor did they conduct basic eye screenings. Conclusions Improving provider-patient interactions and developing public health messages about eye diseases and preventive eye care can facilitate increased use of appropriate eye care services. PMID:18241139

Incidence of short-term complications and associated factors after primary trabeculectomy in Chiang Mai University Hospital.

PubMed

Leeungurasatien, Thidarat; Khunsongkiet, Preeyanuch; Pathanapitoon, Kassara; Wiwatwongwana, Damrong

2016-10-01

To determine the incidence of early postoperative complications and associated factors after primary trabeculectomy in Thai glaucoma patients. This was a retrospective observational study performed in Chiang Mai University Hospital. One hundred and eighteen glaucoma patients participated in the study. All glaucoma patients underwent primary trabeculectomy with mitomycin C (MMC) using fornix-based conjunctival flap technique between December 2011 and May 2013. Surgical complications during the first 3 months of follow-up were recorded, and associated risk factors were analyzed. The incidence of posttrabeculectomy complications was the main outcome measure. One hundred and eighteen eyes of 118 patients were included. Early postoperative complications developed in 55 eyes (56.7%). Complications included hypotony (25 eyes, 27.2%), serous choroidal detachment (CD) (14 eyes, 15.6%), subconjunctival hemorrhage (12 eyes, 13.0%), hyphema (11 eyes, 12.4%), bleb leak (8 eyes, 8.8%), encapsulated bleb (2 eyes, 2.2%), aqueous misdirection (1 eyes, 1.1%), corneal epithelial defect (1 eyes, 1.1%), and overfiltration (1 eyes, 1.1%). There were no reported cases of endophthalmitis or blebitis. Hypotony was associated with serous CD (P = 0.006), and hyphema was associated with neovascular glaucoma (NVG) patients (P = 0.009). NVG was not associated with the increased rate of surgical failure (P = 0.083). The incidence of early complications after first-time trabeculectomy with MMC was high (56.7%) in this Thai clinic setting, but most were transient and self-limited conditions. The correlations between hypotony and CD as well as hyphema and NVG were compatible with the previous studies.

Interocular suppression in strabismic amblyopia results in an attenuated and delayed hemodynamic response function in early visual cortex.

PubMed

Farivar, Reza; Thompson, Benjamin; Mansouri, Behzad; Hess, Robert F

2011-12-20

Factors such as strabismus or anisometropia during infancy can disrupt normal visual development and result in amblyopia, characterized by reduced visual function in an otherwise healthy eye and often associated with persistent suppression of inputs from the amblyopic eye by those from the dominant eye. It has become evident from fMRI studies that the cortical response to stimulation of the amblyopic eye is also affected. We were interested to compare the hemodynamic response function (HRF) of early visual cortex to amblyopic vs. dominant eye stimulation. In the first experiment, we found that stimulation of the amblyopic eye resulted in a signal that was both attenuated and delayed in its time to peak. We postulated that this delay may be due to suppressive effects of the dominant eye and, in our second experiment, measured the cortical response of amblyopic eye stimulation under two conditions--where the dominant eye was open and seeing a static pattern (high suppression) or where the dominant eye was patched and closed (low suppression). We found that the HRF in response to amblyopic eye stimulation depended on whether the dominant eye was open. This effect was manifested as both a delayed HRF under the suppressed condition and an amplitude reduction.

Visual Data Mining: An Exploratory Approach to Analyzing Temporal Patterns of Eye Movements

ERIC Educational Resources Information Center

Yu, Chen; Yurovsky, Daniel; Xu, Tian

2012-01-01

Infant eye movements are an important behavioral resource to understand early human development and learning. But the complexity and amount of gaze data recorded from state-of-the-art eye-tracking systems also pose a challenge: how does one make sense of such dense data? Toward this goal, this article describes an interactive approach based on…

FOUR-YEAR INCIDENCE AND PROGRESSION OF AGE-RELATED MACULAR DEGENERATION: THE LOS ANGELES LATINO EYE STUDY

PubMed Central

Varma, Rohit; Foong, Athena W.P.; Lai, Mei-Ying; Choudhury, Farzana; Klein, Ronald; Azen, Stanley P.

2011-01-01

Purpose To estimate 4-year incidence and progression of early and advanced age-related macular degeneration (AMD). Design Population-based cohort study. Methods A comprehensive ophthalmologic examination including stereoscopic fundus photography was performed on adult Latinos at baseline and follow-up. Photographs were graded using a modified Wisconsin Age-Related Maculopathy Grading System. For estimations of incidence and progression of AMD, the Age Related Eye Disease Study Scale was used. Main outcome measures are incidence and progression of early AMD (drusen type, drusen size, and retinal pigmentary abnormalities) and advanced AMD (exudative AMD and geographic atrophy). Results 4,658/6100 (76%) completed the follow-up examination. The 4-year incidence of early AMD was 7.5% (95%CI:6.6,8.4) and advanced AMD was 0.2% (95%CI:0.1,0.4). Progression of any AMD occurred in 9.3% (95%CI:8.4,10.3) of at-risk participants. Incidence and progression increased with age. Incidence of early AMD in the second eye (10.8%) was higher than incidence in the first eye (6.9%). Baseline presence of soft indistinct large drusen≥250μm in diameter was more likely to predict the 4-year incidence of pigmentary abnormalities, geographic atrophy, and exudative AMD than smaller or hard or soft distinct drusen. Conclusions Age-specific incidence and progression of AMD in Latinos are lower than in non-Hispanic whites. While incident early AMD is more often unilateral, the risk of its development in the second is higher than in the first eye. Older persons and those with soft indistinct large drusen had a higher risk of developing advanced AMD compared to those who were younger and did not have soft indistinct large drusen. PMID:20399926

Dry eye after laser in-situ keratomileusis.

PubMed

Raoof, Duna; Pineda, Roberto

2014-01-01

Laser-assisted in-situ keratomileusis (LASIK) is one of the most commonly performed refractive procedures with excellent visual outcomes. Dry eye syndrome is one of the most frequently seen complications after LASIK, with most patients developing at least some mild dry eye symptoms postoperatively. To achieve improved visual outcomes and greater patient satisfaction, it is essential to identify patients prone to dry eyes preoperatively, and initiate treatment early in the course. Enhanced understanding of the pathophysiology of post-LASIK dry eye will help advance our approach to its management.

Astigmatism in the Early Treatment for Retinopathy of Prematurity Study: findings to 3 years of age

PubMed Central

Davitt, Bradley V.; Dobson, Velma; Quinn, Graham E.; Hardy, Robert J.; Tung, Betty; Good, William V.

2009-01-01

Purpose To examine the prevalence of astigmatism (≥ 1.00 diopter (D)) and high astigmatism (≥ 2.00 D) at 6 and 9 months post-term and 2 and 3 years postnatal, in preterm children with birth weight < 1251g who developed high-risk prethreshold retinopathy of prematurity (ROP) and participated in the Early Treatment for ROP (ETROP) Study. Design Randomized controlled clinical trial Participants 401 infants who developed prethreshold ROP in one or both eyes and were randomized after they were determined to have a high risk (≥ 15%) of poor structural outcome without treatment, using the RM-ROP2 risk management program. Refractive error was measured by cycloplegic retinoscopy. Eyes with additional retinal, glaucoma, or cataract surgery were excluded. Intervention Eyes were randomized to receive laser photocoagulation at high-risk prethreshold ROP (early treated (ET)) or to be conventionally managed (CM), receiving treatment only if threshold ROP developed. Main Outcome Measures Astigmatism and high astigmatism at each visit. Astigmatism was classified as “with-the rule” (75° – 105° (WTR)), “against-the-rule” (0° – 15° and 165° – 180° (ATR), or “oblique” (16° – 74° and 106° – 164° (OBL)). Results The prevalence of astigmatism in ET and CM eyes was similar at each test age. For both groups, there was an increase in prevalence of astigmatism from approximately 32% at 6 months to approximately 42% by 3 years, mostly occurring between 6 and 9 months. Among eyes that could be refracted, astigmatism was not influenced by zone of acute-phase ROP, presence of plus disease, or retinal residua of ROP. Eyes with astigmatism and high astigmatism most often had WTR astigmatism. Conclusions By age 3 years, nearly 43% of eyes treated at high-risk prethreshold ROP developed astigmatism ≥ 1.00 D and nearly 20% had astigmatism ≥ 2.00 D. Presence of astigmatism was not influenced by timing of treatment of acute-phase ROP, characteristics of acute-phase or cicatricial ROP. These findings reinforce the need for follow-up eye examinations in infants with high risk prethreshold ROP. PMID:19091409

Long-term visual outcomes in extremely low-birth-weight children (an American Ophthalmological Society thesis).

PubMed

Spencer, Rand

2006-01-01

The goal is to analyze the long-term visual outcome of extremely low-birth-weight children. This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at >/=36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision. Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 +/- 36 months, and 183 eyes had recognition acuity testing at 76 +/- 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were /=3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at >/=3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at 28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity. Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of

Genetic analysis of fibroblast growth factor signaling in the Drosophila eye.

PubMed

Mukherjee, T; Choi, I; Banerjee, Utpal

2012-01-01

The development of eyes in Drosophila involves intricate epithelial reorganization events for accurate positioning of cells and proper formation and organization of ommatidial clusters. We demonstrate that Branchless (Bnl), the fibroblast growth factor ligand, regulates restructuring events in the eye disc primordium from as early as the emergence of clusters from a morphogenetic front to the cellular movements during pupal eye development. Breathless (Btl) functions as the fibroblast growth factor receptor to mediate Bnl signal, and together they regulate expression of DE-cadherin, Crumbs, and Actin. In addition, in the eye Bnl regulates the temporal onset and extent of retinal basal glial cell migration by activating Btl in the glia. We hypothesized that the Bnl functions in the eye are Hedgehog dependent and represent novel aspects of Bnl signaling not explored previously.

ASSOCIATION BETWEEN VISUAL FUNCTION AND SUBRETINAL DRUSENOID DEPOSITS IN NORMAL AND EARLY AGE-RELATED MACULAR DEGENERATION EYES.

PubMed

Neely, David; Zarubina, Anna V; Clark, Mark E; Huisingh, Carrie E; Jackson, Gregory R; Zhang, Yuhua; McGwin, Gerald; Curcio, Christine A; Owsley, Cynthia

2017-07-01

To examine the association between subretinal drusenoid deposits (SDDs) identified by multimodal retinal imaging and visual function in older eyes with normal macular health or in the earliest phases of age-related macular degeneration (AMD). Age-related macular degeneration status for each eye was defined according to the Age-Related Eye Disease Study (AREDS) 9-step classification system (normal = Step 1, early AMD = Steps 2-4) based on color fundus photographs. Visual functions measured were best-corrected photopic visual acuity, contrast and light sensitivity, mesopic visual acuity, low-luminance deficit, and rod-mediated dark adaptation. Subretinal drusenoid deposits were identified through multimodal imaging (color fundus photographs, infrared reflectance and fundus autofluorescence images, and spectral domain optical coherence tomography). The sample included 1,202 eyes (958 eyes with normal health and 244 eyes with early AMD). In normal eyes, SDDs were not associated with any visual function evaluated. In eyes with early AMD, dark adaptation was markedly delayed in eyes with SDDs versus no SDD (a 4-minute delay on average), P = 0.0213. However, this association diminished after age adjustment, P = 0.2645. Other visual functions in early AMD eyes were not associated with SDDs. In a study specifically focused on eyes in normal macular health and in the earliest phases of AMD, early AMD eyes with SDDs have slower dark adaptation, largely attributable to the older ages of eyes with SDD; they did not exhibit deficits in other visual functions. Subretinal drusenoid deposits in older eyes in normal macular health are not associated with any visual functions evaluated.

The Early Development of Sight-Reading Skills in Adulthood: A Study of Eye Movements

ERIC Educational Resources Information Center

Penttinen, Marjaana; Huovinen, Erkki

2011-01-01

In this study the effects of skill development on the eye movements of beginning adult sight-readers were examined, focusing on changes in the allocation of visual attention within metrical units as well as in the processing of larger melodic intervals. The participants were future elementary school teachers, taking part in a 9-month-long music…

A Dosing Study of Bevacizumab for Retinopathy of Prematurity: Late Recurrences and Additional Treatments.

PubMed

Wallace, David K; Dean, Trevano W; Hartnett, Mary Elizabeth; Kong, Lingkun; Smith, Lois E; Hubbard, G Baker; McGregor, Mary Lou; Jordan, Catherine O; Mantagos, Iason S; Bell, Edward F; Kraker, Raymond T

2018-06-07

Intravitreal bevacizumab is increasingly used to treat severe retinopathy of prematurity (ROP), but it enters the bloodstream, and there is concern that it may alter development of other organs. Previously we reported short-term outcomes of 61 infants enrolled in a dose de-escalation study, and we report the late recurrences and additional treatments. Masked, multicenter, dose de-escalation study. A total of 61 premature infants with type 1 ROP. If type 1 ROP was bilateral at enrollment, then the study eye was randomly selected. In the study eye, bevacizumab intravitreal injections were given at de-escalating doses of 0.25 mg, 0.125 mg, 0.063 mg, or 0.031 mg; if needed, fellow eyes received 1 dose level higher: 0.625 mg, 0.25 mg, 0.125 mg, or 0.063 mg, respectively. After 4 weeks, additional treatment was at the discretion of the investigator. Early and late ROP recurrences, additional treatments, and structural outcomes after 6 months. Of 61 study eyes, 25 (41%; 95% confidence interval [CI], 29%-54%) received additional treatment: 3 (5%; 95% CI, 1%-14%) for early failure (within 4 weeks), 11 (18%; 95% CI, 9%-30%) for late recurrence of ROP (after 4 weeks), and 11 (18%; 95% CI, 9%-30%) for persistent avascular retina. Re-treatment for early failure or late recurrence occurred in 2 of 11 eyes (18%; 95% CI, 2%-52%) treated with 0.25 mg, 4 of 16 eyes (25%; 95% CI, 7%-52%) treated with 0.125 mg, 8 of 24 eyes (33%; 95% CI, 16%-55%) treated with 0.063 mg, and 0 (0%; 95% CI, 0%-31%) of 10 eyes treated with 0.031 mg. By 6 months corrected age, 56 of 61 study eyes had regression of ROP with normal posterior poles, 1 study eye had developed a Stage 5 retinal detachment, and 4 infants had died of preexisting medical conditions. Retinal structural outcomes are very good after low-dose bevacizumab treatment for ROP, although many eyes received additional treatment. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Eye movement accuracy determines natural interception strategies.

PubMed

Fooken, Jolande; Yeo, Sang-Hoon; Pai, Dinesh K; Spering, Miriam

2016-11-01

Eye movements aid visual perception and guide actions such as reaching or grasping. Most previous work on eye-hand coordination has focused on saccadic eye movements. Here we show that smooth pursuit eye movement accuracy strongly predicts both interception accuracy and the strategy used to intercept a moving object. We developed a naturalistic task in which participants (n = 42 varsity baseball players) intercepted a moving dot (a "2D fly ball") with their index finger in a designated "hit zone." Participants were instructed to track the ball with their eyes, but were only shown its initial launch (100-300 ms). Better smooth pursuit resulted in more accurate interceptions and determined the strategy used for interception, i.e., whether interception was early or late in the hit zone. Even though early and late interceptors showed equally accurate interceptions, they may have relied on distinct tactics: early interceptors used cognitive heuristics, whereas late interceptors' performance was best predicted by pursuit accuracy. Late interception may be beneficial in real-world tasks as it provides more time for decision and adjustment. Supporting this view, baseball players who were more senior were more likely to be late interceptors. Our findings suggest that interception strategies are optimally adapted to the proficiency of the pursuit system.

Excess caffeine exposure impairs eye development during chick embryogenesis

PubMed Central

Ma, Zheng-lai; Wang, Guang; Cheng, Xin; Chuai, Manli; Kurihara, Hiroshi; Lee, Kenneth Ka Ho; Yang, Xuesong

2014-01-01

Caffeine has been an integral component of our diet and medicines for centuries. It is now known that over consumption of caffeine has detrimental effects on our health, and also disrupts normal foetal development in pregnant mothers. In this study, we investigated the potential teratogenic effect of caffeine over-exposure on eye development in the early chick embryo. Firstly, we demonstrated that caffeine exposure caused chick embryos to develop asymmetrical microphthalmia and induced the orbital bone to develop abnormally. Secondly, caffeine exposure perturbed Pax6 expression in the retina of the developing eye. In addition, it perturbed the migration of HNK-1+ cranial neural crest cells. Pax6 is an important gene that regulates eye development, so altering the expression of this gene might be the cause for the abnormal eye development. Thirdly, we found that reactive oxygen species (ROS) production was significantly increased in eye tissues following caffeine treatment, and that the addition of anti-oxidant vitamin C could rescue the eyes from developing abnormally in the presence of caffeine. This suggests that excess ROS induced by caffeine is one of the mechanisms involved in the teratogenic alterations observed in the eye during embryogenesis. In sum, our experiments in the chick embryo demonstrated that caffeine is a potential teratogen. It causes asymmetrical microphthalmia to develop by increasing ROS production and perturbs Pax6 expression. PMID:24636305

Genetic Analysis of Fibroblast Growth Factor Signaling in the Drosophila Eye

PubMed Central

Mukherjee, T.; Choi, I.; Banerjee, Utpal

2012-01-01

The development of eyes in Drosophila involves intricate epithelial reorganization events for accurate positioning of cells and proper formation and organization of ommatidial clusters. We demonstrate that Branchless (Bnl), the fibroblast growth factor ligand, regulates restructuring events in the eye disc primordium from as early as the emergence of clusters from a morphogenetic front to the cellular movements during pupal eye development. Breathless (Btl) functions as the fibroblast growth factor receptor to mediate Bnl signal, and together they regulate expression of DE-cadherin, Crumbs, and Actin. In addition, in the eye Bnl regulates the temporal onset and extent of retinal basal glial cell migration by activating Btl in the glia. We hypothesized that the Bnl functions in the eye are Hedgehog dependent and represent novel aspects of Bnl signaling not explored previously. PMID:22384378

Unilateral Amblyopia Affects Two Eyes: Fellow Eye Deficits in Amblyopia.

PubMed

Meier, Kimberly; Giaschi, Deborah

2017-03-01

Unilateral amblyopia is a visual disorder that arises after selective disruption of visual input to one eye during critical periods of development. In the clinic, amblyopia is understood as poor visual acuity in an eye that was deprived of pattern vision early in life. By its nature, however, amblyopia has an adverse effect on the development of a binocular visual system and the interactions between signals from two eyes. Visual functions aside from visual acuity are impacted, and many studies have indicated compromised sensitivity in the fellow eye even though it demonstrates normal visual acuity. While these fellow eye deficits have been noted, no overarching theory has been proposed to describe why and under what conditions the fellow eye is impacted by amblyopia. Here, we consider four explanations that may account for decreased fellow eye sensitivity: the fellow eye is adversely impacted by treatment for amblyopia; the maturation of the fellow eye is delayed by amblyopia; fellow eye sensitivity is impacted for visual functions that rely on binocular cortex; and fellow eye deficits reflect an adaptive mechanism that works to equalize the sensitivity of the two eyes. To evaluate these ideas, we describe five visual functions that are commonly reported to be deficient in the amblyopic eye (hyperacuity, contrast sensitivity, spatial integration, global motion, and motion-defined form), and unify the current evidence for fellow eye deficits. Further research targeted at exploring fellow eye deficits in amblyopia will provide us with a broader understanding of normal visual development and how amblyopia impacts the developing visual system.

Different modes of APC/C activation control growth and neuron-glia interaction in the developing Drosophila eye.

PubMed

Neuert, Helen; Yuva-Aydemir, Yeliz; Silies, Marion; Klämbt, Christian

2017-12-15

The development of the nervous system requires tight control of cell division, fate specification and migration. The anaphase-promoting complex/cyclosome (APC/C) is an E3 ubiquitin ligase that affects different steps of cell cycle progression, as well as having postmitotic functions in nervous system development. It can therefore link different developmental stages in one tissue. The two adaptor proteins, Fizzy/Cdc20 and Fizzy-related/Cdh1, confer APC/C substrate specificity. Here, we show that two distinct modes of APC/C function act during Drosophila eye development. Fizzy/Cdc20 controls the early growth of the eye disc anlage and the concomitant entry of glial cells onto the disc. In contrast, fzr/cdh1 acts during neuronal patterning and photoreceptor axon growth, and subsequently affects neuron-glia interaction. To further address the postmitotic role of Fzr/Cdh1 in controlling neuron-glia interaction, we identified a series of novel APC/C candidate substrates. Four of our candidate genes are required for fzr/cdh1 -dependent neuron-glia interaction, including the dynein light chain Dlc90F Taken together, our data show how different modes of APC/C activation can couple early growth and neuron-glia interaction during eye disc development. © 2017. Published by The Company of Biologists Ltd.

Pleiotropic functions of embryonic sonic hedgehog expression link jaw and taste bud amplification with eye loss during cavefish evolution.

PubMed

Yamamoto, Yoshiyuki; Byerly, Mardi S; Jackman, William R; Jeffery, William R

2009-06-01

This study addresses the role of sonic hedgehog (shh) in increasing oral-pharyngeal constructive traits (jaws and taste buds) at the expense of eyes in the blind cavefish Astyanax mexicanus. In cavefish embryos, eye primordia degenerate under the influence of hyperactive Shh signaling. In concert, cavefish show amplified jaw size and taste bud numbers as part of a change in feeding behavior. To determine whether pleiotropic effects of hyperactive Shh signaling link these regressive and constructive traits, shh expression was compared during late development of the surface-dwelling (surface fish) and cave-dwelling (cavefish) forms of Astyanax. After an initial expansion along the midline of early embryos, shh was elevated in the oral-pharyngeal region in cavefish and later was confined to taste buds. The results of shh inhibition and overexpression experiments indicate that Shh signaling has an important role in oral and taste bud development. Conditional overexpression of an injected shh transgene at specific times in development showed that taste bud amplification and eye degeneration are sensitive to shh overexpression during the same early developmental period, although taste buds are not formed until much later. Genetic crosses between cavefish and surface fish revealed an inverse relationship between eye size and jaw size/taste bud number, supporting a link between oral-pharyngeal constructive traits and eye degeneration. The results suggest that hyperactive Shh signaling increases oral and taste bud amplification in cavefish at the expense of eyes. Therefore, selection for constructive oral-pharyngeal traits may be responsible for eye loss during cavefish evolution via pleiotropic function of the Shh signaling pathway.

The fascinating early history of optics! Archaeological optics 2009: our knowledge of the early history of lenses, mirrors, and artificial eyes!

NASA Astrophysics Data System (ADS)

Enoch, Jay M.

2009-08-01

The early history of optics and vision science (older term: physiological optics) is indeed fascinating. The earliest known true lenses have been found in "eyes" of Egyptian statues which contain superb, complex, and well-polished eye-lens units. The oldest ones known are dated circa 2575 BCE = BC, Dynasty IV, Old Kingdom. These eye-lens units induce a fascinating and powerful visual illusion, but they are just too good to have been the first lenses, or even the first lenses of this design! So saying, no earlier dateable lenses have been found in Egypt or elsewhere. Recently, at the Boston Museum of Fine Arts, the writer noted a previously undetected lens in this series (a first in the Western Hemisphere). Oddly, dateable simpler magnifying lenses and burning glasses seem to have appeared later in time (?)! Manufactured mirrors are quite a bit older, dating from circa 6000 BCE in atal Hyk, located in south-central modern-day Turkey. Using these ancient mirrors, the image quality obtained is remarkable! Recently discovered ancient artificial eyes, located, in situ, in exhumed corpses, have been dated circa 3000 BCE (one discovered in Iran) 5000 BCE (one found in Spain). On the 3000 BCE artificial eye, there are drawn light rays (the writer believes these to be the oldest known depiction of light rays!) spreading out from (or passing into) the iris/ pupil border! Added interesting aspects associated with the early development of light-rays are considered. Thus, early optics can be readily traced back to the Neolithic era (the new stone age), and in some cases before that time period. We have deep roots indeed!

Outcomes following acute primary angle closure in an Asian population.

PubMed

Tan, Anna M; Loon, Seng C; Chew, Paul T K

2009-07-01

Data regarding development of primary angle closure glaucoma (PACG) following acute primary angle closure (APAC) is conflicting. This study looks at outcomes after an APAC episode with a secondary aim to identify any risk factors that could predict progression to PACG. This is a retrospective review of the charts of consecutive patients who were diagnosed with APAC from December 2003 to June 2006. All were treated in a standard manner with initial intensive medical therapy or laser iridoplasty followed by early laser peripheral iridotomy within 24 h of presentation. Forty-two eyes of 41 patients were analysed. The mean follow-up period was 27.3 +/- 16.2 months. Nine eyes (21.4%) developed an increase in intraocular pressure (IOP) within a mean of 11.9 months (median 5 months) after resolution of APAC. Eight eyes went on to have trabeculectomy or glaucoma drainage device. At final follow up, the mean IOP of attack eye was 13.3 +/- 2.92 mmHg. None of the eyes, including those that underwent surgery, required topical medication to control IOP. Thirty-eight eyes (90.5%) have BCVA of 6/6 to 6/12. The duration of symptoms before presentation (P = 0.00) and duration taken to abort the acute attack (P = 0.01) were found to be significantly associated with development of PACG. The results of this study suggest that outcomes following successful treatment of APAC may not be as poor as described previously. Early aggressive management of the acute episode may have a role to play in preventing development of PACG after APAC.

Opening a Window into Reading Development: Eye Movements’ Role Within a Broader Literacy Research Framework

PubMed Central

Miller, Brett; O’Donnell, Carol

2013-01-01

The cumulative body of eye movement research provides significant insight into how readers process text. The heart of this work spans roughly 40 years reflecting the maturity of both the topics under study and experimental approaches used to investigate reading. Recent technological advancements offer increased flexibility to the field providing the potential to more concertedly study reading and literacy from an individual differences perspective. Historically, eye movement research focused far less on developmental issues related to individual differences in reading; however, this issue and the broader change it represents signal a meaningful transition inclusive of individual differences. The six papers in this special issue signify the recent, increased attention to and recognition of eye movement research’s transition to emphasize individual differences in reading while appreciating early contributions (e.g., Rayner, 1986) in this direction. We introduce these six papers and provide some historical context for the use of eye movement methodology to examine reading and context for the eye movement field’s early transition to examining individual differences, culminating in future research recommendations. PMID:24391304

Opening a Window into Reading Development: Eye Movements' Role Within a Broader Literacy Research Framework.

PubMed

Miller, Brett; O'Donnell, Carol

2013-01-01

The cumulative body of eye movement research provides significant insight into how readers process text. The heart of this work spans roughly 40 years reflecting the maturity of both the topics under study and experimental approaches used to investigate reading. Recent technological advancements offer increased flexibility to the field providing the potential to more concertedly study reading and literacy from an individual differences perspective. Historically, eye movement research focused far less on developmental issues related to individual differences in reading; however, this issue and the broader change it represents signal a meaningful transition inclusive of individual differences. The six papers in this special issue signify the recent, increased attention to and recognition of eye movement research's transition to emphasize individual differences in reading while appreciating early contributions (e.g., Rayner, 1986) in this direction. We introduce these six papers and provide some historical context for the use of eye movement methodology to examine reading and context for the eye movement field's early transition to examining individual differences, culminating in future research recommendations.

Monochromatic ocular wave aberrations in young monkeys

PubMed Central

Ramamirtham, Ramkumar; Kee, Chea-su; Hung, Li-Fang; Qiao-Grider, Ying; Roorda, Austin; Smith, Earl L.

2006-01-01

High-order monochromatic aberrations could potentially influence vision-dependent refractive development in a variety of ways. As a first step in understanding the effects of wave aberration on refractive development, we characterized the maturational changes that take place in the high-order aberrations of infant rhesus monkey eyes. Specifically, we compared the monochromatic wave aberrations of infant and adolescent animals and measured the longitudinal changes in the high-order aberrations of infant monkeys during the early period when emmetropization takes place. Our main findings were that (1) adolescent monkey eyes have excellent optical quality, exhibiting total RMS errors that were slightly better than those for adult human eyes that have the same numerical aperture and (2) shortly after birth, infant rhesus monkeys exhibited relatively larger magnitudes of high-order aberrations predominately spherical aberration, coma, and trefoil, which decreased rapidly to assume adolescent values by about 200 days of age. The results demonstrate that rhesus monkey eyes are a good model for studying the contribution of individual ocular components to the eye’s overall aberration structure, the mechanisms responsible for the improvements in optical quality that occur during early ocular development, and the effects of high-order aberrations on ocular growth and emmetropization. PMID:16750549

Complementary Gli activity mediates early patterning of the mouse visual system.

PubMed

Furimsky, Marosh; Wallace, Valerie A

2006-03-01

The Sonic hedgehog (Shh) signaling pathway plays a key role in the development of the vertebrate central nervous system, including the eye. This pathway is mediated by the Gli transcription factors (Gli1, Gli2, and Gli3) that differentially activate and repress the expression of specific downstream target genes. In this study, we investigated the roles of the three vertebrate Glis in mediating midline Shh signaling in early ocular development. We examined the ocular phenotypes of Shh and Gli combination mutant mouse embryos and monitored proximodistal and dorsoventral patterning by the expression of specific eye development regulatory genes using in situ hybridization. We show that midline Shh signaling relieves the repressor activity of Gli3 adjacent to the midline and then promotes eye pattern formation through the nonredundant activities of all three Gli proteins. Gli3, in particular, is required to specify the dorsal optic stalk and to define the boundary between the optic stalk and the optic cup.

Loss of Neurofilament Labeling in the Primary Visual Cortex of Monocularly Deprived Monkeys

PubMed Central

Duffy, Kevin R.; Livingstone, Margaret S.

2009-01-01

Visual experience during early life is important for the development of neural organizations that support visual function. Closing one eye (monocular deprivation) during this sensitive period can cause a reorganization of neural connections within the visual system that leaves the deprived eye functionally disconnected. We have assessed the pattern of neurofilament labeling in monocularly deprived macaque monkeys to examine the possibility that a cytoskeleton change contributes to deprivation-induced reorganization of neural connections within the primary visual cortex (V-1). Monocular deprivation for three months starting around the time of birth caused a significant loss of neurofilament labeling within deprived-eye ocular dominance columns. Three months of monocular deprivation initiated in adulthood did not produce a loss of neurofilament labeling. The evidence that neurofilament loss was found only when deprivation occurred during the sensitive period supports the notion that the loss permits restructuring of deprived-eye neural connections within the visual system. These results provide evidence that, in addition to reorganization of LGN inputs, the intrinsic circuitry of V-1 neurons is altered when monocular deprivation occurs early in development. PMID:15563721

LONG-TERM VISUAL OUTCOMES IN EXTREMELY LOW-BIRTH-WEIGHT CHILDREN (AN AMERICAN OPHTHALMOLOGICAL SOCIETY THESIS)

PubMed Central

Spencer, Rand

2006-01-01

Purpose The goal is to analyze the long-term visual outcome of extremely low-birth-weight children. Methods This is a retrospective analysis of eyes of extremely low-birth-weight children on whom vision testing was performed. Visual outcomes were studied by analyzing acuity outcomes at ≥36 months of adjusted age, correlating early acuity testing with final visual outcome and evaluating adverse risk factors for vision. Results Data from 278 eyes are included. Mean birth weight was 731g, and mean gestational age at birth was 26 weeks. 248 eyes had grating acuity outcomes measured at 73 ± 36 months, and 183 eyes had recognition acuity testing at 76 ± 39 months. 54% had below normal grating acuities, and 66% had below normal recognition acuities. 27% of grating outcomes and 17% of recognition outcomes were ≤20/200. Abnormal early grating acuity testing was predictive of abnormal grating (P < .0001) and recognition (P = .0001) acuity testing at ≥3 years of age. A slower-than-normal rate of early visual development was predictive of abnormal grating acuity (P < .0001) and abnormal recognition acuity (P < .0001) at ≥3 years of age. Eyes diagnosed with maximal retinopathy of prematurity in zone I had lower acuity outcomes (P = .0002) than did those with maximal retinopathy of prematurity in zone II/III. Eyes of children born at ≤28 weeks gestational age had 4.1 times greater risk for abnormal recognition acuity than did those of children born at >28 weeks gestational age. Eyes of children with poorer general health after premature birth had a 5.3 times greater risk of abnormal recognition acuity. Conclusions Long-term visual development in extremely low-birth-weight infants is problematic and associated with a high risk of subnormal acuity. Early acuity testing is useful in identifying children at greatest risk for long-term visual abnormalities. Gestational age at birth of ≤ 28 weeks was associated with a higher risk of an abnormal long-term outcome. PMID:17471358

Drosophila Pax6 promotes development of the entire eye-antennal disc, thereby ensuring proper adult head formation

PubMed Central

Zhu, Jinjin; Palliyil, Sneha; Ran, Chen; Kumar, Justin P.

2017-01-01

Paired box 6 (Pax6) is considered to be the master control gene for eye development in all seeing animals studied so far. In vertebrates, it is required not only for lens/retina formation but also for the development of the CNS, olfactory system, and pancreas. Although Pax6 plays important roles in cell differentiation, proliferation, and patterning during the development of these systems, the underlying mechanism remains poorly understood. In the fruit fly, Drosophila melanogaster, Pax6 also functions in a range of tissues, including the eye and brain. In this report, we describe the function of Pax6 in Drosophila eye-antennal disc development. Previous studies have suggested that the two fly Pax6 genes, eyeless (ey) and twin of eyeless (toy), initiate eye specification, whereas eyegone (eyg) and the Notch (N) pathway independently regulate cell proliferation. Here, we show that Pax6 controls eye progenitor cell survival and proliferation through the activation of teashirt (tsh) and eyg, thereby indicating that Pax6 initiates both eye specification and proliferation. Although simultaneous loss of ey and toy during early eye-antennal disc development disrupts the development of all head structures derived from the eye-antennal disc, overexpression of N or tsh in the absence of Pax6 rescues only antennal and head epidermis development. Furthermore, overexpression of tsh induces a homeotic transformation of the fly head into thoracic structures. Taking these data together, we demonstrate that Pax6 promotes development of the entire eye-antennal disc and that the retinal determination network works to repress alternative tissue fates, which ensures proper development of adult head structures. PMID:28584125

Ocular allergy and dry eye syndrome.

PubMed

Bielory, Leonard

2004-10-01

Ocular allergy is a common clinical disorder that includes dry eye syndrome in its differential diagnosis. While ocular allergy treatments have continued to evolve since the early 1990s when the new prescription topical agents became available, there have been no major advances in the treatment of dry eye syndrome other than changes in the chemical structures of various artificial tear formulations. This review is timely and relevant due to the recent FDA approval of several new agents for the treatment of dry eye syndrome. The literature reviewed brings the practicing allergist/clinical immunologist up to date on the recent understanding that T-cell activation plays a key role in dry eye syndrome immunopathophysiology. In addition, the parallel novel treatment developments are discussed, including new formulations for tear substitutes, topical cyclosporine A and purinergic receptor (P2Y2) agonists. The recent developments bode well for patients who are referred for ocular allergy, including dry eye syndrome. A new formulation for a tear substitute that generates a 'soft gel' covering the ocular surface (in situ) is ideal for early forms of dry syndrome, while topical cyclosporine is the first new real prescription treatment for patients with moderate to severe forms of dry eye. Another potential agent to revolutionize the treatment of various disorders is based on the discovery of the purinergic receptor agonists. This is not only relevant for the production of mucin and the change in tear fluid content, but it may also have implications for other sinopulmonary disorders such as cystic fibrosis and chronic sinusitis.

Visual acuity at 10 years in Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) study eyes: effect of retinal residua of retinopathy of prematurity.

PubMed

Dobson, Velma; Quinn, Graham E; Summers, C Gail; Hardy, Robert J; Tung, Betty

2006-02-01

To describe recognition (letter) acuity at age 10 years in eyes with and without retinal residua of retinopathy of prematurity (ROP). Presence and severity of ROP residua were documented by a study ophthalmologist. Masked testers measured monocular recognition visual acuity (Early Treatment of Diabetic Retinopathy Study) when the children were 10 years old. Two hundred forty-seven of 255 surviving Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) randomized trial patients participated. A reference group of 102 of 104 Philadelphia-based CRYO-ROP study participants who did not develop ROP was also tested. More severe retinal residua were associated with worse visual acuity, regardless of whether retinal ablation was performed to treat the severe acute-phase ROP. However, within each ROP residua category, there was a wide range of visual acuity results. This is the first report of the relation between visual acuity (Early Treatment of Diabetic Retinopathy Study charts) and structural abnormalities related to ROP in a large group of eyes that developed threshold ROP in the perinatal period. Visual deficits are greater in eyes with more severe retinal residua than in eyes with mild or no residua. However, severity of ROP residua does not predict the visual acuity of an individual eye because within a single residua category, acuity may range from near normal to blind.

Analysis of novel Sjogren's syndrome autoantibodies in patients with dry eyes.

PubMed

Everett, Sandra; Vishwanath, Sahana; Cavero, Vanessa; Shen, Long; Suresh, Lakshmanan; Malyavantham, Kishore; Lincoff-Cohen, Norah; Ambrus, Julian L

2017-03-07

Dry eye is a common problem in Ophthalmology and may occur for many reasons including Sjogren's syndrome (SS). Recent studies have identified autoantibodies, anti-salivary gland protein 1 (SP1), anti-carbonic anhydrase 6 (CA6) and anti-parotid secretory protein (PSP), which occur early in the course of SS. The current studies were designed to evaluate how many patients with idiopathic dry eye and no evidence of systemic diseases from a dry eye practice have these autoantibodies. Patients from a dry eye clinic and normal controls were assessed by Schirmer's test for tear flow. Sera were assessed for autoantibodies using ELISA assays. Statistics was performed with Prism 7 software and student's unpaired t test. In this study 60% of the dry eye patients expressed one of these autoantibodies. Only 30% expressed one of the autoantibodies associated with long-standing SS, which are included in the diagnostic criteria for SS, anti-Ro and anti-La. Patients with disease for less than 2 years and mild dry eyes did not express anti-Ro or anti-La, while 25% expressed anti-SP1. Similar observations, with smaller numbers, were made when patients had not only dry eye but also dry mouth. Antibodies to SP1, CA6 and PSP occur in some patients with idiopathic dry eyes. Further studies will be needed to determine how many of these patients go on to develop systemic manifestations of SS. Testing for these autoantibodies may allow early recognition of patients with SS. This will lead to improved management of the patients and the development of new strategies to maintain normal lacrimal and salivary gland function in patients with SS.

Diagnostic ability of macular ganglion cell-inner plexiform layer thickness in glaucoma suspects.

PubMed

Xu, Xiaoyu; Xiao, Hui; Guo, Xinxing; Chen, Xiangxi; Hao, Linlin; Luo, Jingyi; Liu, Xing

2017-12-01

The purpose is to assess the diagnostic ability for early glaucoma of macular ganglion cell-inner plexiform layer (GCIPL) thickness in a Chinese population including glaucoma suspects.A total of 367 eyes with primary open-angle glaucoma (168 early glaucoma, 78 moderate glaucoma, and 121 advanced glaucoma), 52 eyes with ocular hypertension (OHT), 59 eyes with enlarged cup-to-disc ratio (C/D), and 225 normal eyes were included. GCIPL thickness (average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal), retinal nerve fiber layer (RNFL) thickness, and optic nerve head (ONH) parameters were measured using Cirrus high-definition optical coherence tomography (OCT) and compared. The diagnostic ability of OCT parameters was assessed by area under receiver operating characteristic curve (AUROC) in 3 distinguishing groups: normal eyes and eyes with early glaucoma, normal eyes and eyes with glaucoma regardless of disease stage, and nonglaucomatous eyes (normal eyes, eyes with OHT, and enlarged C/D) and early glaucomatous eyes.Glaucomatous eyes showed a significant reduction in GCIPL thickness compared with nonglaucomatous eyes. In all 3 distinguishing groups, best-performing parameters of GCIPL thickness, RNFL thickness, and ONH parameters were minimum GCIPL thickness (expressed in AUROC, 0.899, 0.952, and 0.900, respectively), average RNFL thickness (0.904, 0.953, and 0.892, respectively), and rim area (0.861, 0.925, and 0.824, respectively). There was no statistical significance of AUROC between minimum GCIPL thickness and average RNFL thickness (all P > .05).GCIPL thickness could discriminate early glaucoma from normal and glaucoma suspects with good sensitivity and specificity. The glaucoma diagnostic ability of GCIPL thickness was comparable to that of RNFL thickness. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Introduction to the development of intraocular lens

NASA Astrophysics Data System (ADS)

Li, Yifan; Peng, Runling; Hu, Shuilan; Wei, Maowei; Chen, Jiabi

2013-08-01

In order to cure the cataract disease or injuries in eyes, intraocular lens(IOL) has been studied all the time to replace the crystalline lens in human eyes. Researches on IOL are started early from 19th century, and it develops greatly in the hundreds years after. This article introduces several main kinds of IOLs that appear in the development history of IOL, and raises the double-liquid zoom IOL based on electrowetting, which will be the trend of IOL study.

The Utrecht Ophthalmic Hospital and the development of the ophthalmoscope.

PubMed

Den Tonkelaar, I; Henkes, H E; van Leersum, G K

1988-01-01

The first useful table model ophthalmoscope was designed by Donders and the instrumentmaker Epkens. With the use of this instrument Donders' pupil Van Trigt made the first drawings of the normal and pathological fundus of the eye. His contribution was of great importance for the early diffusion of knowledge of the fundus of the eye.

Young Children's Visual Attention to Environmental Print as Measured by Eye Tracker Analysis

ERIC Educational Resources Information Center

Neumann, Michelle M.; Acosta, Camillia; Neumann, David L.

2014-01-01

Environmental print, such as signs and product labels, consist of both print and contextual cues designed to attract the visual attention of the reader. However, contextual cues may draw young children's attention away from the print, thus questioning the value of environmental print in early reading development. Eye tracker technology was used to…

Molecular aspects of eye evolution and development: from the origin of retinal cells to the future of regenerative medicine.

PubMed

Ohuchi, Hideyo

2013-01-01

A central issue of evolutionary developmental biology is how the eye is diverged morphologically and functionally. However, the unifying mechanisms or schemes that govern eye diversification remain unsolved. In this review, I first introduce the concept of evolutionary developmental biology of the eye with a focus on photoreception, the fundamental property of retinal cells. Second, I summarize the early development of vertebrate eyes and the role of a homeobox gene, Lhx1, in subdivision of the retina into 2 domains, the neural retina and retinal pigmented epithelium of the optic primordium. The 2 retinal domains are essential components of the eye as they are found in such prototypic eyes as the extant planarian eye. Finally, I propose the presence of novel retinal cell subtypes with photosensory functions based on our recent work on atypical photopigments (opsins) in vertebrates. Since human diseases are attributable to the aberration of various types of cells due to alterations in gene expression, understanding the precise mechanisms of cellular diversification and unraveling the molecular profiles of cellular subtypes are essential to future regenerative medicine.

Comparison of 1000-Centistoke versus 5000-Centistoke Silicone Oil in Complex Retinal Detachment Surgery.

PubMed

Zafar, Shakir; Shakir, Munira; Mahmood, Syed Asaad; Amin, Saima; Iqbal, Zafar

2016-01-01

To compare the efficacy and complications of using 1000-centistoke versus 5000-centistoke silicone oil for complex retinal detachment repair. Case series. LRBT Tertiary Eye Hospital, Karachi, from January 2007 to June 2013. Eighty-five eyes (85 patients) presenting with superior rhegmatogenous retinal detachments associated with PVR grades B and C (involving not more than 3 clock hours) were randomized to either 1000 centistokes (n=44) or 5000 centistokes (n=41) silicone oil group. All patients underwent 23-gauge pars plana vitrectomy surgery with silicone oil intraocular tamponade. Patient data was analysed at 18 months post-operatively. IBM SPSS 21 was used for data analysis. There were 52 male and 33 female patients aged between 22 and 70 years (45.2 ±16.2). After the first surgery, successful reattachment of the retina was achieved in 67 eyes (78.8%); of which 35 eyes were in 1000-centistoke and 32 eyes in 5000-centistoke groups. Mean pre-operative Best Corrected Visual Acuity (BCVA) was 1.63 ±0.54 which was improved to a mean post-operative BCVAof 1.46 ±0.78 (1.42 ±0.74 in 1000-centistoke group; 1.49 ±0.78 in 5000 centistoke group). The 1000-centistoke group had a significantly higher frequency of oil emulsification which necessitated early removal of silicone oil. There were 66 eyes (77%) with at least one complication (34 eyes in 1000-centistoke group; 32 eyes in 5000-centistoke group) including cataract, corneal abnormalities, raised IOP, hypotony, vitreous haemorrhage and retinal redetachment. Although visual and anatomical outcomes were comparable between the two groups, the 1000-centistoke silicone oil group developed early oil emulsification necessitating its early removal.

Observations on the Relationship between Anisometropia, Amblyopia and Strabismus

PubMed Central

Smith, Earl L; Hung, Li-Fang; Arumugam, Baskar; Wensveen, Janice M.; Chino, Yuzo M.; Harwerth, Ronald S.

2017-01-01

We investigated the potential causal relationships between anisometropia, amblyopia and strabismus, specifically to determine whether either amblyopia or strabismus interfered with emmetropization. We analyzed data from non-human primates that were relevant to the co-existence of anisometropia, amblyopia and strabismus in children. We relied on interocular comparisons of spatial vision and refractive development in animals reared with 1) monocular form deprivation; 2) anisometropia optically imposed by either contact lenses or spectacle lenses; 3) organic amblyopia produced by laser ablation of the fovea; and 4) strabismus that was either optically imposed with prisms or produced by either surgical or pharmacological manipulation of the extraocular muscles. Hyperopic anisometropia imposed early in life produced amblyopia in a dose-dependent manner. However, when potential methodological confounds were taken into account, there was no support for the hypothesis that the presence of amblyopia interferes with emmetropization or promotes hyperopia or that the degree of image degradation determines the direction of eye growth. To the contrary, there was strong evidence that amblyopic eyes were able to detect the presence of a refractive error and alter ocular growth to eliminate the ametropia. On the other hand, early onset strabismus, both optically and surgically imposed, disrupted the emmetropization process producing anisometropia. In surgical strabismus, the deviating eyes were typically more hyperopic than their fellow fixating eyes. The results show that early hyperopic anisometropia is a significant risk factor for amblyopia. Early esotropia can trigger the onset of both anisometropia and amblyopia. However, amblyopia, in isolation, does not pose a significant risk for the development of hyperopia or anisometropia. PMID:28404522

Observations on the relationship between anisometropia, amblyopia and strabismus.

PubMed

Smith, Earl L; Hung, Li-Fang; Arumugam, Baskar; Wensveen, Janice M; Chino, Yuzo M; Harwerth, Ronald S

2017-05-01

We investigated the potential causal relationships between anisometropia, amblyopia and strabismus, specifically to determine whether either amblyopia or strabismus interfered with emmetropization. We analyzed data from non-human primates that were relevant to the co-existence of anisometropia, amblyopia and strabismus in children. We relied on interocular comparisons of spatial vision and refractive development in animals reared with 1) monocular form deprivation; 2) anisometropia optically imposed by either contact lenses or spectacle lenses; 3) organic amblyopia produced by laser ablation of the fovea; and 4) strabismus that was either optically imposed with prisms or produced by either surgical or pharmacological manipulation of the extraocular muscles. Hyperopic anisometropia imposed early in life produced amblyopia in a dose-dependent manner. However, when potential methodological confounds were taken into account, there was no support for the hypothesis that the presence of amblyopia interferes with emmetropization or promotes hyperopia or that the degree of image degradation determines the direction of eye growth. To the contrary, there was strong evidence that amblyopic eyes were able to detect the presence of a refractive error and alter ocular growth to eliminate the ametropia. On the other hand, early onset strabismus, both optically and surgically imposed, disrupted the emmetropization process producing anisometropia. In surgical strabismus, the deviating eyes were typically more hyperopic than their fellow fixating eyes. The results show that early hyperopic anisometropia is a significant risk factor for amblyopia. Early esotropia can trigger the onset of both anisometropia and amblyopia. However, amblyopia, in isolation, does not pose a significant risk for the development of hyperopia or anisometropia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Theory for the alignment of cortical feature maps during development.

PubMed

Bressloff, Paul C; Oster, Andrew M

2010-08-01

We present a developmental model of ocular dominance column formation that takes into account the existence of an array of intrinsically specified cytochrome oxidase blobs. We assume that there is some molecular substrate for the blobs early in development, which generates a spatially periodic modulation of experience-dependent plasticity. We determine the effects of such a modulation on a competitive Hebbian mechanism for the modification of the feedforward afferents from the left and right eyes. We show how alternating left and right eye dominated columns can develop, in which the blobs are aligned with the centers of the ocular dominance columns and receive a greater density of feedforward connections, thus becoming defined extrinsically. More generally, our results suggest that the presence of periodically distributed anatomical markers early in development could provide a mechanism for the alignment of cortical feature maps.

Changes in tear volume and ocular symptoms of patients receiving oral anticancer drug S-1.

PubMed

Kuriki, Reiko; Hata, Tsuyoshi; Nakayama, Kinuyo; Ito, Yuichi; Misawa, Kazunari; Ito, Seiji; Tatematsu, Michiko; Kaneda, Norio

2018-01-01

Most eye disorders are not fatal but may deteriorate the quality of life of a patient. The eye disorder that is most frequently reported in the cancer chemotherapy is associated with the combination of tegafur/gimeracil/potassium oxonate (S-1). However, preventive methods or treatment methods for the eye disorder have not yet been established. This study aimed to determine changes in tear volume and subjective ocular symptoms during the treatment period in patients receiving S-1 monotherapy for early detection of adverse effects in the eye and establishment of its treatment methods. This study included eleven patients receiving S-1 monotherapy as a postoperative adjuvant chemotherapy for gastric cancer. Six subjective ocular symptoms including watering eyes were evaluated and changes in tear volume measured by the Schirmer's test in patients receiving S-1 during the treatment period. In the present study, the patients were divided into "no watering eyes" (patients not experienced watering eyes) group and "watering eyes" (patients experienced watering eyes even once) group. Six out of eleven patients developed watering eyes after receiving S-1 monotherapy. Among these, the earliest onset occurred on the 2nd week after oral administration. Watering eyes and eye discharge were highly related in patients having a trouble in daily life due to the decreased QOL. Changes in tear volume in the "watering eyes" group significantly increased compared to the "no watering eyes" group during the treatment period, especially when the patients had no subjective symptom of the increased tear volume. It is essential to prevent eye disorders including watering eyes as an adverse effect of S-1 administration. The present study recommends that the tear volume should be periodically measured using Schirmer's test, and the patient should be interviewed regarding the subjective ocular symptoms for the early detection of watering eyes caused by S-1 administration. If the tear volume can not be measured periodically, medical staffs should pay attention to the patient with eye discharge.

Sensitivity and specificity for detecting early glaucoma in eyes with high myopia from normative database of macular ganglion cell complex thickness obtained from normal non-myopic or highly myopic Asian eyes.

PubMed

Nakanishi, Hideo; Akagi, Tadamichi; Hangai, Masanori; Kimura, Yugo; Suda, Kenji; Kumagai, Kyoko Kawashima; Morooka, Satoshi; Ikeda, Hanako Ohashi; Yoshimura, Nagahisa

2015-07-01

We aimed to determine the sensitivity and specificity of the normative database of non-myopic and highly myopic eyes of the macular ganglion cell complex (mGCC) thickness embedded in the NIDEK RS-3000 spectral-domain optical coherence tomography (SD-OCT) for detecting early glaucoma in highly myopic eyes. Forty-seven highly myopic eyes (axial length ≥26.0 mm) of 47 subjects were studied. The SD-OCT images were used to determine the mGCC thickness within a 9-mm diameter circle centered on the fovea. The sensitivity and specificity of the non-myopic database were compared to that of the highly myopic database for distinguishing the early glaucomatous eyes from the non-glaucomatous eyes. The mGCC scans were classified as abnormal if at least one of the eight sectors of the significance map was < 1 % of the normative thickness. Twenty-one eyes were diagnosed to be non-glaucomatous and 26 eyes to have early glaucoma. . The average mGCC thickness was significantly thinner (80.9 ± 8.5 μm) in the early glaucoma group than in the non-glaucomatous group (91.2 ± 7.5 μm; p <1 × 10(-4)). The sensitivity was 96.2 % and specificity was 47.6 % when the non-myopic database was used, and the sensitivity was 92.3 % and the specificity was 90.5 % when the highly myopic database was used. The difference in the specificity was significant (p < 0.01). The significantly higher specificity of the myopic normative database for detecting early glaucoma in highly myopic eyes will lead to fewer false positive diagnoses. The database obtained from highly myopic eyes should be used when evaluating the mGCC thickness of highly myopic eyes.

MACULAR HOLE FORMATION FOLLOWED BY SPONTANEOUS CLOSURE AFTER PNEUMATIC RETINOPEXY IN A PATIENT WITH DIABETIC MACULAR EDEMA.

PubMed

Cohen, Michael N; Baumal, Caroline R

2018-05-10

To report early formation and spontaneous closure of a full-thickness macular hole that developed after successful pneumatic retinopexy in a patient who had been undergoing treatment for diabetic macular edema. Case report of a 68-year-old man with bilateral nonproliferative diabetic retinopathy who was currently undergoing anti-vascular endothelial growth factor treatment for bilateral diabetic macular edema. On presentation, visual acuity was 20/200 in the left eye, and examination revealed a bullous, macula-off retinal detachment with a single horseshoe tear at 12 o'clock in the left eye. Pneumatic retinopexy was performed followed by laser augmentation 3 days later. Three weeks postoperatively, he returned with visual acuity of 20/50 and a full-thickness macular hole in the left eye. Although he elected for initial observation, he returned 2 weeks later with visual acuity of 20/50 in both eyes and a retinal detachment with a single break at 10 o'clock in the right eye. The macular hole in the left eye had spontaneously resolved. Pneumatic retinopexy was performed to the right eye. Over 1 year after bilateral pneumatic retinopexy, his retina remains without recurrence of a macular hole in the left eye. In the early postoperative period after pneumatic retinopexy to repair a retinal detachment, a macular hole can form and spontaneously close.

Six-Year Incidence of Age-Related Macular Degeneration in Asian Malays: The Singapore Malay Eye Study.

PubMed

Cheung, Chui Ming Gemmy; Ong, Peng Guan; Neelam, Kumari; Tan, Pok Chien; Shi, Yuan; Mitchell, Paul; Wang, Jie Jin; Sabanayagam, Charumathi; Cheng, Ching-Yu; Wong, Tien Yin

2017-09-01

To determine the 6-year incidence of early and late age-related macular degeneration (AMD) in a Singaporean Malay population and to validate the Age-Related Eye Disease Study (AREDS) simplified severity scale in Asians. Prospective, population cohort study. The Singapore Malay Eye Study baseline participants (age, ≥40 years; 2006-2008) were followed up in 2011 through 2013, and 1901 of 3280 of eligible participants (72.1%) took part. Fundus photographs were graded using the Wisconsin AMD grading system. Incidence of early and late AMD. Gradable fundus photographs were available for 1809 participants who attended both baseline and 6-year follow-up examinations. The age-standardized incidences of early and late AMD were 5.89% (95% confidence interval [CI], 4.81-7.16) and 0.76% (95% CI, 0.42-1.29), respectively. The 5-year age-standardized incidence of early AMD (calculated based on the 6-year incidence) was lower in our population (5.58%; 95% CI, 4.43-7.01) compared with the Beaver Dam Eye Study population (8.19%). The incidence of late AMD in our population was similar to that of the Beaver Dam Eye Study population (0.98% [95% CI, 0.49-1.86] vs. 0.91%), the Blue Mountains Eye Study population (1.10% [95% CI, 0.52-9.56] vs. 1.10%), and the Hisayama Study population (1.09% [95% CI, 0.54-4.25] vs. 0.84%). The incidence of late AMD increased markedly with increasing baseline AREDS score (step 0, 0.23%; step 4, 9.09%). This study documented the incidence of early and late AMD in a Malay population. The AREDS simplified severity scale is useful in predicting the risk of late AMD development in Asians. Copyright © 2017 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

The importance of the eyes: communication skills in infants of blind parents.

PubMed

Senju, Atsushi; Tucker, Leslie; Pasco, Greg; Hudry, Kristelle; Elsabbagh, Mayada; Charman, Tony; Johnson, Mark H

2013-06-07

The effects of selectively different experience of eye contact and gaze behaviour on the early development of five sighted infants of blind parents were investigated. Infants were assessed longitudinally at 6-10, 12-15 and 24-47 months. Face scanning and gaze following were assessed using eye tracking. In addition, established measures of autistic-like behaviours and standardized tests of cognitive, motor and linguistic development, as well as observations of naturalistic parent-child interaction were collected. These data were compared with those obtained from a larger group of sighted infants of sighted parents. Infants with blind parents did not show an overall decrease in eye contact or gaze following when they observed sighted adults on video or in live interactions, nor did they show any autistic-like behaviours. However, they directed their own eye gaze somewhat less frequently towards their blind mothers and also showed improved performance in visual memory and attention at younger ages. Being reared with significantly reduced experience of eye contact and gaze behaviour does not preclude sighted infants from developing typical gaze processing and other social-communication skills. Indeed, the need to switch between different types of communication strategy may actually enhance other skills during development.

The Speed Death of the Eye: The Ideology of Hollywood Film Special Effects

ERIC Educational Resources Information Center

Blackmore, Tim

2007-01-01

In the late 20th and early 21st centuries, increased computing power has made possible extraordinary leaps in film special effects. This article argues that special effects developed since the beginning of digital animation, when coupled with standard editing room techniques (jump cuts, cutaways), have brought us to an era where the eye cannot…

The Development of Research Networks among Early-Career Faculty Members in the Science, Engineering and Health Disciplines

ERIC Educational Resources Information Center

Bankart, Charles Allen Swanson

2012-01-01

The purpose of this study was to develop a better understanding of the patterns and processes of collaboration in the performance of research, as well as to understand why and how early-career faculty members engage in collaborative partnerships. With an eye toward institutional policy and academic programming, special emphasis was placed on how…

Nanosecond pulsed electric field suppresses development of eyes and germ cells through blocking synthesis of retinoic acid in Medaka (Oryzias latipes).

PubMed

Shiraishi, Eri; Hosseini, Hamid; Kang, Dong K; Kitano, Takeshi; Akiyama, Hidenori

2013-01-01

Application of nanosecond pulsed electric fields (nsPEFs) has attracted rising attention in various scientific fields including medical, pharmacological, and biological sciences, although its effects and molecular mechanisms leading to the effects remain poorly understood. Here, we show that a single, high-intensity (10-30 kV/cm), 60-ns PEF exposure affects gene expression and impairs development of eyes and germ cells in medaka (Oryzias latipes). Exposure of early blastula stage embryos to nsPEF down-regulated the expression of several transcription factors which are essential for eye development, causing abnormal eye formation. Moreover, the majority of the exposed genetic female embryos showed a fewer number of germ cells similar to that of the control (unexposed) genetic male at 9 days post-fertilization (dpf). However, all-trans retinoic acid (atRA) treatment following the exposure rescued proliferation of germ cells and resumption of normal eye development, suggesting that the phenotypes induced by nsPEF are caused by a decrease of retinoic acid levels. These results confirm that nsPEFs induce novel effects during embryogenesis in medaka.

Training the intelligent eye: understanding illustrations in early modern astronomy texts.

PubMed

Crowther, Kathleen M; Barker, Peter

2013-09-01

Throughout the early modern period, the most widely read astronomical textbooks were Johannes de Sacrobosco's De sphaera and the Theorica planetarum, ultimately in the new form introduced by Georg Peurbach. This essay argues that the images in these texts were intended to develop an "intelligent eye." Students were trained to transform representations of specific heavenly phenomena into moving mental images of the structure of the cosmos. Only by learning the techniques of mental visualization and manipulation could the student "see" in the mind's eye the structure and motions of the cosmos. While anyone could look up at the heavens, only those who had acquired the intelligent eye could comprehend the divinely created order of the universe. Further, the essay demonstrates that the visual program of the Sphaera and Theorica texts played a significant and hitherto unrecognized role in later scientific work. Copernicus, Galileo, and Kepler all utilized the same types of images in their own texts to explicate their ideas about the cosmos.

[Clinical features and treatment of choroidal metastasis].

PubMed

Wang, Guang-lu; Wang, Ming-yang; Wei, Wen-bin

2009-03-01

To assess the clinical features and management of choroidal metastasis. Fundus examination was performed in 49 patients (66 eyes) with choroidal metastasis. Fundus fluorescein angiography (FFA) was performed in 44 cases, combined with indocyanine green angiography (ICGA) examination in 12 cases. B-scan ultrasound examination was performed in 8 cases. Transpupillary thermotherapy (TTT) was performed in 24 eyes, combined with photo-dynamic therapy in one eye. Plaque radio-therapy was used in one eye. The parameters of treatment for TTT were 1.2 - 3 mm spot size, 450 - 1000 mV, 60 s; 2 sessions of TTT in 2 eyes and 3 sessions in 3 eyes. Fourteen cases were male and 35 cases were female. Both eyes were affected in 17 cases (34.7%). Age ranged from 23 - 74 years old with an average of 47 years. The visual acuity was 0.05 or less in 13 eyes; 0.06 - 0.2 in 22 eyes and 0.3 or more in 31 eyes. Primary tumours were found in 40 cases (81.6%) (surgical excision in 25 cases), consisting of breast carcinoma in 16 cases (32.7%), lung carcinoma in 14 cases (28.6%), hepatoma and cholangiocarcinoma in 3 cases, colon and stomach carcinomas in 3 cases, gynecologic appendix carcinoma (including 1 case of ovarian mucous cyst adenocarcinoma) in 2 cases, nasopharyngeal adenocarcinoma in 1 case, vertebra tumor in 1 case, undetected in 5 cases (10.2%) and under detection in 4 cases (8.2%). The fundus had 1 lesion in 58 eyes (58/66 = 87.8%), 2 lesions in 4 eyes (4/66 = 6.0%), 3 or more lesions in 2 eyes (including 7 lesions in 1 eye). According to the location and development status of the lesions, they could be divided into solitary type, 39 eyes (39/66 = 59.1%); diffuse type, 19 eyes (19/66 = 28.8%); and early type, 8 eyes (8/66 = 12.1%). FFA examination: early stage lesions showed hypofluorescence and later stage lesions showed moderate to strong hyperfluorescence. In 8 cases of solitary lesions, the size of the lesion measured by B-scan averaged 11.5 mm x 10.5 mm x 3.6 mm with the maximal height at 4.9 mm. The tumor became flattened and vision remained stable at 3 months after plaque radiotherapy in 1 case. Three cases were followed-up for 2, 3, and 4 months after TTT treatment. The lesions remained stable with vision unchanged or slightly decreased. The choroidal metastasis has specific clinical features. The classification of metastatic lesions into solitary, diffuse and early types is helpful for the evaluation of the disease process. The primary tumor can be found in 80% of cases. The most common primary cancer is breast carcinoma, followed by lung carcinoma. These two cancers account for 75% of primary tumors. In solitary type and early type lesions, TTT combines with systemic treatment could result in regression of lesions, saving of vision and improvement of the life quality.

Early Childhood Intervention: Shaping the Future for Children with Special Needs and Their Families

ERIC Educational Resources Information Center

Eidelman, Steven, Ed.; Kaczmarek, Louise A., Ed.; Maude, Susan P., Ed.

2011-01-01

This eye-opening set looks at young children with special needs, their families, and the laws, policies, programs, and services designed to help them. It is scientifically known that early childhood is a time of significant brain development. That makes it especially crucial that children with special needs be recognized early so that appropriate…

Optical aberrations, retinal image quality and eye growth: Experimentation and modeling

NASA Astrophysics Data System (ADS)

Tian, Yibin

2007-12-01

Retinal image quality is important for normal eye growth. Optical aberrations are of interest for two reasons: first, they degrade retinal images; second, they might provide some cues to defocus. Higher than normal ocular aberrations have been previously associated with human myopia. However, these studies were cross-sectional in design, and only reported aberrations in terms of root mean square (RMS) errors of Zernike coefficients, a poor metric of optical quality. This dissertation presents results from investigations of ocular optical aberrations, retinal image quality and eye growth in chicks and humans. A number of techniques were utilized, including Shack-Hartmann aberrometry, high-frequency A-scan ultrasonography, ciliary nerve section (CNX), photorefractive keratectomy (PRK) as well as computer simulations and modeling. A technique to extract light scatter information from Shack-Hartmann images was also developed. The main findings of the dissertation are summarized below. In young chicks, most ocular aberrations decreased with growth in both normal and CNX eyes, and there were diurnal fluctuations in some aberrations. Modeling suggested active reduction in higher order aberrations (HOAs) during early development. Although CNX eyes manifested greater than normal HOAs, they showed near normal growth. Retinal image degradation varied greatly among individual eyes post-PRK in young chicks. Including light scatter information into analyses of retinal image quality better estimated the latter. Albino eyes showed more severe retinal image degradation than normal eyes, due to increased optical aberrations and light scatter, but their growth was similar to those of normal eyes, implying that they are relatively insensitive to retina image quality. Although the above results questioned the influence of optical aberrations on early ocular growth, some optical quality metrics, derived from optical aberrations data, could predict how much the eyes of young chicks subsequently elongated. The performance of some focus measures was very poor when non-defocus aberrations exceeded a certain level; presumably, these non-defocus aberrations might interfere with the eye's ability to interpret defocus. In anisomyopic human adults, more myopic eyes had larger anterior and vitreous chambers, greater astigmatism, and more positive spherical aberration. However, compared to isometropes, only interocular differences in spherical equivalent refractive errors were significantly increased.

Early Experience with Technology-Based Eye Care Services (TECS): A Novel Ophthalmologic Telemedicine Initiative.

PubMed

Maa, April Y; Wojciechowski, Barbara; Hunt, Kelly J; Dismuke, Clara; Shyu, Jason; Janjua, Rabeea; Lu, Xiaoqin; Medert, Charles M; Lynch, Mary G

2017-04-01

The aging population is at risk of common eye diseases, and routine eye examinations are recommended to prevent visual impairment. Unfortunately, patients are less likely to seek care as they age, which may be the result of significant travel and time burdens associated with going to an eye clinic in person. A new method of eye-care delivery that mitigates distance barriers and improves access was developed to improve screening for potentially blinding conditions. We present the quality data from the early experience (first 13 months) of Technology-Based Eye Care Services (TECS), a novel ophthalmologic telemedicine program. With TECS, a trained ophthalmology technician is stationed in a primary care clinic away from the main hospital. The ophthalmology technician follows a detailed protocol that collects information about the patient's eyes. The information then is interpreted remotely. Patients with possible abnormal findings are scheduled for a face-to-face examination in the eye clinic. Any patient with no known ocular disease who desires a routine eye screening examination is eligible. Technology-Based Eye Care Services was established in 5 primary care clinics in Georgia surrounding the Atlanta Veterans Affairs hospital. Four program operation metrics (patient satisfaction, eyeglass remakes, disease detection, and visit length) and 2 access-to-care metrics (appointment wait time and no-show rate) were tracked. Care was rendered to 2690 patients over the first 13 months of TECS. The program has been met with high patient satisfaction (4.95 of 5). Eyeglass remake rate was 0.59%. Abnormal findings were noted in 36.8% of patients and there was >90% agreement between the TECS reading and the face-to-face findings of the physician. TECS saved both patient (25% less) and physician time (50% less), and access to care substantially improved with 99% of patients seen within 14 days of contacting the eye clinic, with a TECS no-show rate of 5.2%. The early experience with TECS has been promising. Tele-ophthalmology has the potential to improve operational efficiency, reduce cost, and significantly improve access to care. Although further study is necessary, TECS shows potential to help prevent avoidable vision loss. Published by Elsevier Inc.

[The effect of yellow filter intraocular lens on the macula after cataract phacoemulsification in patients with age macular degeneration].

PubMed

Shpak, A A; Maliugin, B É; Fadeeva, T V

2012-01-01

Macula changes diagnosed with optical coherence tomography (OCT) within a year after cataract phacoemulsification (PE) with intraocular lens implantation with and without yellow filter are presented. 32 patients (36 eyes) with early stages of age macular degeneration (AMD) were included into the experimental group and 35 patients (36 eyes) served as controls. IOLs with yellow filter were implanted in 21 eyes, and in 15 cases IOLs without filter were used in each group. According to OCT data thickening of fovea and increasing of macula volume developed within 6 months after cataract PE. Implantation of yellow filter IOLs reduced the intensity of these changes after surgery in patients with AMD. The progression of early AMD into advanced stages within a year after PE was not observed.

Dry Eye Disease Incidence Associated with Chronic Graft-Host Disease: Nonconcurrent Cohort Study (An American Ophthalmological Society Thesis)

PubMed Central

Mian, Shahzad I.; De la Parra-Colín, Paola; De Melo-Franco, Rafael; Johnson, Christopher; Barrientos-Gutierrez, Tonatiuh

2015-01-01

Purpose: To determine if chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT) is associated with stable or progressive dry eye disease and to determine the true incidence in patients with no prior history of dry eye disease. Methods: A nonconcurrent cohort study at a single institution with 136 patients who had no previous history of dry eye disease before HSCT. Survival analysis was used to estimate dry eye disease incidence. The incidence rate was calculated using life tables as the number of observed dry eye disease cases divided by the person-time at risk accumulated by the cohort. Transition probabilities were calculated from time of transplant to time of diagnosis, and then to last recorded visit. Results: Incidence rate was 0.8 cases of dry eye disease per person-year, and half of the population at risk developed dry eye disease during the first 10 months post transplant. Time to develop dry eye disease was 2.5 months for mild dry eye disease, 9.6 months for moderate dry eye disease, and 13.2 months for severe dry eye disease. In terms of cumulative incidence, 73% of subjects developed dry eye disease (50% mild, 16% moderate, and 7% severe) at the time of diagnosis. Conclusions: Our findings suggest that dry eye disease associated with cGVHD is an extremely frequent event and shows a wide spectrum of severity, with a mild form presenting early and a moderate to severe form presenting later after HSCT. These findings need to be studied further to elucidate if these are two different pathophysiological entities or just different expressions of the same pathology. PMID:27507907

Eye Lens Radiation Exposure in Greek Interventional Cardiology Article.

PubMed

Thrapsanioti, Zoi; Askounis, Panagiotis; Datseris, Ioannis; Diamanti, Ramza Anastasia; Papathanasiou, Miltiadis; Carinou, Eleftheria

2017-07-01

The lens of the eye is one of the radiosensitive tissues of the human body; if exposed to ionizing radiation can develop radiation-induced cataract at early ages. This study was held in Greece and included 44 Interventional Cardiologists (ICs) and an unexposed to radiation control group of 22 persons. Of the note, 26 ICs and the unexposed individuals underwent special eye examinations. The detected lens opacities were classified according to LOCS III protocol. Additionally, the lens doses of the ICs were measured using eye lens dosemeters. The mean dose to the lenses of the ICs per month was 0.83 ± 0.59 mSv for the left and 0.35 ± 0.38 mSv for the right eye, while the annual doses ranged between 0.7 and 11 mSv. Regarding the lens opacities, the two groups did not differ significantly in the prevalence of either nuclear or cortical lens opacities, whereas four ICs were detected with early stage subcapsular sclerosis. Though no statistically difference was observed in the cohort, the measured doses indicate that the eye doses received from the ICs can be significant. To minimize the radiation-induced risk at the eye lenses, the use of protective equipment and appropriate training on this issue is highly recommended. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The developmental emergence of unconscious fear processing from eyes during infancy.

PubMed

Jessen, Sarah; Grossmann, Tobias

2016-02-01

From early in life, emotion detection plays an important role during social interactions. Recently, 7-month-old infants have been shown to process facial signs of fear in others without conscious perception and solely on the basis of their eyes. However, it is not known whether unconscious fear processing from eyes is present before 7months of age or only emerges at around 7months. To investigate this question, we measured 5-month-old infants' event-related potentials (ERPs) in response to subliminally presented fearful and non-fearful eyes and compared these with 7-month-old infants' ERP responses from a previous study. Our ERP results revealed that only 7-month-olds, but not 5-month-olds, distinguished between fearful and non-fearful eyes. Specifically, 7-month-olds' processing of fearful eyes was reflected in early visual processes over occipital cortex and later attentional processes over frontal cortex. This suggests that, in line with prior work on the conscious detection of fearful faces, the brain processes associated with the unconscious processing of fearful eyes develop between 5 and 7months of age. More generally, these findings support the notion that emotion perception and the underlying brain processes undergo critical change during the first year of life. Therefore, the current data provide further evidence for viewing infancy as a formative period in human socioemotional functioning. Copyright © 2015 Elsevier Inc. All rights reserved.

Acquired color vision and visual field defects in patients with ocular hypertension and early glaucoma.

PubMed

Papaconstantinou, Dimitris; Georgalas, Ilias; Kalantzis, George; Karmiris, Efthimios; Koutsandrea, Chrysanthi; Diagourtas, Andreas; Ladas, Ioannis; Georgopoulos, Gerasimos

2009-01-01

To study acquired color vision and visual field defects in patients with ocular hypertension (OH) and early glaucoma. In a prospective study we evaluated 99 eyes of 56 patients with OH without visual field defects and no hereditary color deficiencies, followed up for 4 to 6 years (mean = 4.7 +/- 0.6 years). Color vision defects were studied using a special computer program for Farnsworth-Munsell 100 hue test and visual field tests were performed with Humphrey analyzer using program 30-2. Both tests were repeated every six months. In fifty-six eyes, glaucomatous defects were observed during the follow-up period. There was a statistically significant difference in total error score (TES) between eyes that eventually developed glaucoma (157.89 +/- 31.79) and OH eyes (75.51 +/- 31.57) at the first examination (t value 12.816, p < 0.001). At the same time visual field indices were within normal limits in both groups. In the glaucomatous eyes the earliest statistical significant change in TES was identified at the first year of follow-up and was -20.62 +/- 2.75 (t value 9.08, p < 0.001) while in OH eyes was -2.11 +/- 4.36 (t value 1.1, p = 0.276). Pearson's coefficient was high in all examinations and showed a direct correlation between TES and mean deviation and corrected pattern standard deviation in both groups. Quantitative analysis of color vision defects provides the possibility of follow-up and can prove a useful means for detecting early glaucomatous changes in patients with normal visual fields.

Impaired Eye Region Search Accuracy in Children with Autistic Spectrum Disorders

PubMed Central

Pruett, John R.; Hoertel, Sarah; Constantino, John N.; LaMacchia Moll, Angela; McVey, Kelly; Squire, Emma; Feczko, Eric; Povinelli, Daniel J.; Petersen, Steven E.

2013-01-01

To explore mechanisms underlying reduced fixation of eyes in autism, children with Autistic Spectrum Disorders (ASD) and typically developing children were tested in five visual search experiments: simple color feature; color-shape conjunction; face in non-face objects; mouth region; and eye region. No group differences were found for reaction time profile shapes in any of the five experiments, suggesting intact basic search mechanics in children with ASD. Contrary to early reports in the literature, but consistent with other more recent findings, we observed no superiority for conjunction search in children with ASD. Importantly, children with ASD did show reduced accuracy for eye region search (p = .005), suggesting that eyes contribute less to high-level face representations in ASD or that there is an eye region-specific disruption to attentional processes engaged by search in ASD. PMID:23516446

Impaired eye region search accuracy in children with autistic spectrum disorders.

PubMed

Pruett, John R; Hoertel, Sarah; Constantino, John N; Moll, Angela LaMacchia; McVey, Kelly; Squire, Emma; Feczko, Eric; Povinelli, Daniel J; Petersen, Steven E

2013-01-01

To explore mechanisms underlying reduced fixation of eyes in autism, children with autistic spectrum disorders (ASD) and typically developing children were tested in five visual search experiments: simple color feature; color-shape conjunction; face in non-face objects; mouth region; and eye region. No group differences were found for reaction time profile shapes in any of the five experiments, suggesting intact basic search mechanics in children with ASD. Contrary to early reports in the literature, but consistent with other more recent findings, we observed no superiority for conjunction search in children with ASD. Importantly, children with ASD did show reduced accuracy for eye region search (p = .005), suggesting that eyes contribute less to high-level face representations in ASD or that there is an eye region-specific disruption to attentional processes engaged by search in ASD.

Long-Term Observation of Triplex Surgery for Cataract after Phakic 6H Implantation for Super High Myopia

PubMed Central

Liu, Xin; Wang, Xiaoying; Lu, Yi; Zheng, Tianyu; Zhou, Xingtao

2016-01-01

Purpose. To analyze the safety, effectiveness, and stability of triplex surgery for phakic 6H anterior chamber phakic intraocular lens explantation and phacoemulsification with in-the-bag IOL implantation for super high myopia in long-term observations. Methods. This retrospective case series evaluated 16 eyes of 10 patients who underwent triplex surgery. Best corrected visual acuity (BCVA), endothelial cell density (ECD), and associated adverse events were evaluated. Results. The mean follow-up time after the triplex surgery was 46 ± 14 months. The mean logMAR BCVA was significantly improved after triplex surgery (P = 0.047). One eye developed endophthalmitis five days postoperatively and underwent pars plana vitrectomy (PPV). Five eyes with preoperative severe endothelial cell loss developed corneal decompensation and underwent keratoplasty at a mean time of 9.4 ± 2.6 months after the triplex surgery. One eye had graft failure and underwent a second keratoplasty. The eye developed rhegmatogenous retinal detachment and underwent PPV with silicone oil 18 months later. ECD before the triplex surgery was not significantly different compared with that at last follow-up (P = 0.495) apart from these five eyes. Three eyes (18.8%) developed posterior capsule opacification. Conclusions. Triplex surgery was safe and effective for phakic 6H related complicated cataracts. Early extraction before severe ECD loss is recommended. PMID:27190642

A Model of the Spatio-temporal Dynamics of Drosophila Eye Disc Development.

PubMed

Fried, Patrick; Sánchez-Aragón, Máximo; Aguilar-Hidalgo, Daniel; Lehtinen, Birgitta; Casares, Fernando; Iber, Dagmar

2016-09-01

Patterning and growth are linked during early development and have to be tightly controlled to result in a functional tissue or organ. During the development of the Drosophila eye, this linkage is particularly clear: the growth of the eye primordium mainly results from proliferating cells ahead of the morphogenetic furrow (MF), a moving signaling wave that sweeps across the tissue from the posterior to the anterior side, that induces proliferating cells anterior to it to differentiate and become cell cycle quiescent in its wake. Therefore, final eye disc size depends on the proliferation rate of undifferentiated cells and on the speed with which the MF sweeps across the eye disc. We developed a spatio-temporal model of the growing eye disc based on the regulatory interactions controlled by the signals Decapentaplegic (Dpp), Hedgehog (Hh) and the transcription factor Homothorax (Hth) and explored how the signaling patterns affect the movement of the MF and impact on eye disc growth. We used published and new quantitative data to parameterize the model. In particular, two crucial parameter values, the degradation rate of Hth and the diffusion coefficient of Hh, were measured. The model is able to reproduce the linear movement of the MF and the termination of growth of the primordium. We further show that the model can explain several mutant phenotypes, but fails to reproduce the previously observed scaling of the Dpp gradient in the anterior compartment.

A Method to Quantify Visual Information Processing in Children Using Eye Tracking

PubMed Central

Kooiker, Marlou J.G.; Pel, Johan J.M.; van der Steen-Kant, Sanny P.; van der Steen, Johannes

2016-01-01

Visual problems that occur early in life can have major impact on a child's development. Without verbal communication and only based on observational methods, it is difficult to make a quantitative assessment of a child's visual problems. This limits accurate diagnostics in children under the age of 4 years and in children with intellectual disabilities. Here we describe a quantitative method that overcomes these problems. The method uses a remote eye tracker and a four choice preferential looking paradigm to measure eye movement responses to different visual stimuli. The child sits without head support in front of a monitor with integrated infrared cameras. In one of four monitor quadrants a visual stimulus is presented. Each stimulus has a specific visual modality with respect to the background, e.g., form, motion, contrast or color. From the reflexive eye movement responses to these specific visual modalities, output parameters such as reaction times, fixation accuracy and fixation duration are calculated to quantify a child's viewing behavior. With this approach, the quality of visual information processing can be assessed without the use of communication. By comparing results with reference values obtained in typically developing children from 0-12 years, the method provides a characterization of visual information processing in visually impaired children. The quantitative information provided by this method can be advantageous for the field of clinical visual assessment and rehabilitation in multiple ways. The parameter values provide a good basis to: (i) characterize early visual capacities and consequently to enable early interventions; (ii) compare risk groups and follow visual development over time; and (iii), construct an individual visual profile for each child. PMID:27500922

A Method to Quantify Visual Information Processing in Children Using Eye Tracking.

PubMed

Kooiker, Marlou J G; Pel, Johan J M; van der Steen-Kant, Sanny P; van der Steen, Johannes

2016-07-09

Visual problems that occur early in life can have major impact on a child's development. Without verbal communication and only based on observational methods, it is difficult to make a quantitative assessment of a child's visual problems. This limits accurate diagnostics in children under the age of 4 years and in children with intellectual disabilities. Here we describe a quantitative method that overcomes these problems. The method uses a remote eye tracker and a four choice preferential looking paradigm to measure eye movement responses to different visual stimuli. The child sits without head support in front of a monitor with integrated infrared cameras. In one of four monitor quadrants a visual stimulus is presented. Each stimulus has a specific visual modality with respect to the background, e.g., form, motion, contrast or color. From the reflexive eye movement responses to these specific visual modalities, output parameters such as reaction times, fixation accuracy and fixation duration are calculated to quantify a child's viewing behavior. With this approach, the quality of visual information processing can be assessed without the use of communication. By comparing results with reference values obtained in typically developing children from 0-12 years, the method provides a characterization of visual information processing in visually impaired children. The quantitative information provided by this method can be advantageous for the field of clinical visual assessment and rehabilitation in multiple ways. The parameter values provide a good basis to: (i) characterize early visual capacities and consequently to enable early interventions; (ii) compare risk groups and follow visual development over time; and (iii), construct an individual visual profile for each child.

Identification of cornifelin and early growth response-1 gene as novel biomarkers for in vitro eye irritation using a 3D reconstructed human cornea model MCTT HCE™.

PubMed

Choi, Seunghye; Lee, Miri; Lee, Su-Hyon; Jung, Haeng-Sun; Kim, Seol-Yeong; Chung, Tae-Young; Choe, Tae-boo; Chun, Young-Jin; Lim, Kyung-Min

2015-09-01

Evaluation of the eye irritation is essential in the development of new cosmetic products. Draize rabbit eye irritation test has been widely used in which chemicals are directly applied to rabbit eye, and the symptoms and signs of eyes are scored. However, due to the invasive procedure, it causes substantial pain and discomfort to animals. Recently, we reported in vitro eye irritation test method using a 3D human corneal epithelial model (MCTT HCE™) which is reconstructed from remaining human tissues after a corneal transplantation. This model exhibited an excellent predictive capacity for 25 reference chemicals (sensitivity 100%, specificity 77% and accuracy 88% vs. GHS). To improve the test performance, we explored new biomarkers for the eye irritation through transcriptomic approach. Three surfactants were selected as model eye irritants that include sodium lauryl sulfate, benzalkonium chloride and triton X-100. After test chemicals were treated, we investigated differentially expressed genes through a whole-gene microarray (Affymetrix GeneChip(®) Human Gene 2.0 ST Array, 48,000 probes). As a result, we identified that mRNAs of cornifelin (CNFN), a constituent of the insoluble cornified cell envelope of stratified squamous epithelia, and early growth response-1 (EGR1), a nuclear transcriptional regulator, were significantly up-regulated by all three irritants. Up-regulation of CNFN and EGR1 was further confirmed by Q-RT-PCR, and immunohistochemistry revealed increased level of CNFN in irritant-treated tissues, supporting the relevance of CNFN and EGR1 as new biomarkers for eye irritation.

Effects of aqueous humor hydrodynamics on human eye heat transfer under external heat sources.

PubMed

Tiang, Kor L; Ooi, Ean H

2016-08-01

The majority of the eye models developed in the late 90s and early 00s considers only heat conduction inside the eye. This assumption is not entirely correct, since the anterior and posterior chambers are filled aqueous humor (AH) that is constantly in motion due to thermally-induced buoyancy. In this paper, a three-dimensional model of the human eye is developed to investigate the effects AH hydrodynamics have on the human eye temperature under exposure to external heat sources. If the effects of AH flow are negligible, then future models can be developed without taking them into account, thus simplifying the modeling process. Two types of external thermal loads are considered; volumetric and surface irradiation. Results showed that heat convection due to AH flow contributes to nearly 95% of the total heat flow inside the anterior chamber. Moreover, the circulation inside the anterior chamber can cause an upward shift of the location of hotspot. This can have significant consequences to our understanding of heat-induced cataractogenesis. Copyright © 2016 IPEM. Published by Elsevier Ltd. All rights reserved.

Eye ontogeny in Pleurodema bufoninum: A comparison with Pleurodema somuncurense (Anura, Leptodactylidae).

PubMed

Volonteri, Clara; Barrasso, Diego A; Cotichelli, Leonardo; Basso, Néstor G; Hermida, Gladys N

2017-07-01

Vision is one of the main sensory systems in amphibians, and the eye structure is highly associated with habitat conditions. The ontogeny, as well as the adult structure, of the eye has been studied in only a few species. The life change after metamorphosis is accompanied by changes in the visual environment. The aim of this work is to describe the eye ontogeny of Pleurodema bufoninum and to compare it with that of Pleurodema somuncurense. Specimens of both Pleurodema species were processed for histology analysis at different stages of development, including the tadpole, postmetamorphic, and adult forms. Eyes in both Pleurodema species are composed of the 3 tunics, tunica fibrosa, tunica vasculosa, and tunica interna, and the lens. Additionally, in both, the iris presents a projection on its dorsal and ventral free ends that screens the cornea. This structure has been reported in the eye of several anuran species and is called the umbraculum, meniscus or pupillary nodule. Our results show that the structures related to light capture (retina and lens) appear early in larval life, while the components of the terrestrial-life eye (scleral cartilage, specialized cornea, eyelids, nictitating membrane, and Harderian's gland) do not develop until the metamorphic climax, when the tadpole leaves the water. The adult eyes of P. bufoninum and P. somuncurense are very similar in structure and development. © 2017 Wiley Periodicals, Inc.

Eye lens radiation exposure to interventional cardiologists: a retrospective assessment of cumulative doses.

PubMed

Jacob, Sophie; Donadille, Laurent; Maccia, Carlo; Bar, Olivier; Boveda, Serge; Laurier, Dominique; Bernier, Marie-Odile

2013-03-01

Radiation dose to the eye lens is a crucial issue for interventional cardiologists (ICs) who are exposed during the procedures they perform. This paper presents a retrospective assessment of the cumulative eye lens doses of ICs enrolled in the O'CLOC study for Occupational Cataracts and Lens Opacities in interventional Cardiology. Information on the workload in the catheterisation laboratory, radiation protection equipment, eye lens dose per procedure and dose reduction factors associated with eye-protective equipment were considered. For the 129 ICs at an average age of 51 who had worked for an average period of 22 years, the estimated cumulative eye lens dose ranged from 25 mSv to more than 1600 mSv; the mean ± SD was 423 ± 359 mSv. After several years of practice, without eye protection, ICs may exceed the new ICRP lifetime eye dose threshold of 500 mSv and be at high risk of developing early radiation-induced cataracts. Radiation protection equipment can reduce these doses and should be used routinely.

Progressive Susac syndrome with bilateral visual loss and disability.

PubMed

Entezari, Morteza; Karimi, Saeed; Feizi, Mohammadali

2016-09-01

Susac syndrome (SS) is a rare retinal-cochlear-cerebral disease with an unclear etiology. A 35-year-old man presented with sudden painless vision loss in the right eye and 2 months later in the left eye with hemiparesis, behavioral changes, and hearing loss. Ophthalmic examinations revealed multiple branch retinal artery occlusions (BRAOs) in both eyes. Brain magnetic resonance imaging showed inflammatory changes with multiple "punched-out" lesions in the corpus callosum which confirmed the diagnosis of SS. Despite intravenous and oral corticosteroid therapy, the disease progressed with the development of new BRAOs, low vision in both eyes, and disability. Prompt diagnosis and early treatment may save the vision and even patient's life.

The sophisticated visual system of a tiny Cambrian crustacean: analysis of a stalked fossil compound eye

PubMed Central

Schoenemann, Brigitte; Castellani, Christopher; Clarkson, Euan N. K.; Haug, Joachim T.; Maas, Andreas; Haug, Carolin; Waloszek, Dieter

2012-01-01

Fossilized compound eyes from the Cambrian, isolated and three-dimensionally preserved, provide remarkable insights into the lifestyle and habitat of their owners. The tiny stalked compound eyes described here probably possessed too few facets to form a proper image, but they represent a sophisticated system for detecting moving objects. The eyes are preserved as almost solid, mace-shaped blocks of phosphate, in which the original positions of the rhabdoms in one specimen are retained as deep cavities. Analysis of the optical axes reveals four visual areas, each with different properties in acuity of vision. They are surveyed by lenses directed forwards, laterally, backwards and inwards, respectively. The most intriguing of these is the putatively inwardly orientated zone, where the optical axes, like those orientated to the front, interfere with axes of the other eye of the contralateral side. The result is a three-dimensional visual net that covers not only the front, but extends also far laterally to either side. Thus, a moving object could be perceived by a two-dimensional coordinate (which is formed by two axes of those facets, one of the left and one of the right eye, which are orientated towards the moving object) in a wide three-dimensional space. This compound eye system enables small arthropods equipped with an eye of low acuity to estimate velocity, size or distance of possible food items efficiently. The eyes are interpreted as having been derived from individuals of the early crustacean Henningsmoenicaris scutula pointing to the existence of highly efficiently developed eyes in the early evolutionary lineage leading towards the modern Crustacea. PMID:22048954

Specification of embryonic stem cell-derived tissues into eye fields by Wnt signaling using rostral diencephalic tissue-inducing culture.

PubMed

Sakakura, Eriko; Eiraku, Mototsugu; Takata, Nozomu

2016-08-01

The eyes are subdivided from the rostral diencephalon in early development. How the neuroectoderm regulates this subdivision, however, is largely unknown. Taking advantage of embryonic stem cell (ESC) culture using a Rax reporter line to monitor rostral diencephalon formation, we found that ESC-derived tissues at day 7 grown in Glasgow Minimum Expression Media (GMEM) containing knockout serum replacement (KSR) exhibited higher levels of expression of axin2, a Wnt target gene, than those grown in chemically defined medium (CDM). Surprisingly, Wnt agonist facilitated eye field-like tissue specification in CDM. In contrast, the addition of Wnt antagonist diminished eye field tissue formation in GMEM+KSR. Furthermore, the morphological formation of the eye tissue anlage, including the optic vesicle, was accompanied by Wnt signaling activation. Additionally, using CDM culture, we developed an efficient method for generating Rax+/Chx10+ retinal progenitors, which could become fully stratified retina. Here we provide a new avenue for exploring the mechanisms of eye field specification in vitro. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Grating visual acuity results in the early treatment for retinopathy of prematurity study.

PubMed

Dobson, Velma; Quinn, Graham E; Summers, C Gail; Hardy, Robert J; Tung, Betty; Good, William V

2011-07-01

To compare grating (resolution) visual acuity at 6 years of age in eyes that received early treatment (ET) for high-risk prethreshold retinopathy of prematurity (ROP) with that in eyes that underwent conventional management (CM). In a randomized clinical trial, infants with bilateral, high-risk prethreshold ROP (n = 317) had one eye undergo ET and the other eye undergo CM, with treatment only if ROP progressed to threshold severity. For asymmetric cases (n = 84), the high-risk prethreshold eye was randomized to ET or CM. Grating visual acuity measured at 6 years of age by masked testers using Teller acuity cards. Monocular grating acuity results were obtained from 317 of 370 surviving children (85.6%). Analysis of grating acuity results for all study participants with high-risk prethreshold ROP showed no statistically significant overall benefit of ET (18.1% vs 22.8% unfavorable outcomes; P = .08). When the 6-year grating acuity results were analyzed according to a clinical algorithm (high-risk types 1 and 2 prethreshold ROP), a benefit was seen in type 1 eyes (16.4% vs 25.2%; P = .004) undergoing ET, but not in type 2 eyes (21.3% vs 15.9%; P = .29). Early treatment of eyes with type 1 ROP improves grating acuity outcomes, but ET for eyes with type 2 ROP does not. APPLICATION TO CLINICAL MEDICINE: Type 1 eyes should be treated early; however, based on acuity results at 6 years of age, type 2 eyes should be cautiously monitored for progression to type 1 ROP. Trial Registration clinicaltrials.gov Identifier: NCT00027222.

An Epha4/Sipa1l3/Wnt pathway regulates eye development and lens maturation.

PubMed

Rothe, Melanie; Kanwal, Noreen; Dietmann, Petra; Seigfried, Franziska A; Hempel, Annemarie; Schütz, Desiree; Reim, Dominik; Engels, Rebecca; Linnemann, Alexander; Schmeisser, Michael J; Bockmann, Juergen; Kühl, Michael; Boeckers, Tobias M; Kühl, Susanne J

2017-01-15

The signal-induced proliferation-associated family of proteins comprises four members, SIPA1 and SIPA1L1-3. Mutations of the human SIPA1L3 gene result in congenital cataracts. In Xenopus, loss of Sipa1l3 function led to a severe eye phenotype that was distinguished by smaller eyes and lenses including lens fiber cell maturation defects. We found a direct interaction between Sipa1l3 and Epha4, building a functional platform for proper ocular development. Epha4 deficiency phenocopied loss of Sipa1l3 and rescue experiments demonstrated that Epha4 acts upstream of Sipa1l3 during eye development, with both Sipa1l3 and Epha4 required for early eye specification. The ocular phenotype, upon loss of either Epha4 or Sipa1l3, was partially mediated by rax We demonstrate that canonical Wnt signaling is inhibited downstream of Epha4 and Sipa1l3 during normal eye development. Depletion of either Sipa1l3 or Epha4 resulted in an upregulation of axin2 expression, a direct Wnt/β-catenin target gene. In line with this, Sipa1l3 or Epha4 depletion could be rescued by blocking Wnt/β-catenin or activating non-canonical Wnt signaling. We therefore conclude that this pathomechanism prevents proper eye development and maturation of lens fiber cells, resulting in congenital cataracts. © 2017. Published by The Company of Biologists Ltd.

The Early Development of Joint Attention in Infants with Autistic Disorder Using Home Video Observations and Parental Interview

ERIC Educational Resources Information Center

Clifford, Sally M; Dissanayake, Cheryl

2008-01-01

The aim in the current study was to investigate the early development of joint attention, eye contact and affect during the first 2 years of life, by using retrospective parental interviews and analyses of home videos of infants who were later diagnosed with Autistic Disorder (AD). The 36 children with AD and the 27 matched control children were…

Differential toxicity of copper, zinc, and lead during the embryonic development of Chasmagnathus granulatus (Brachyura, Varunidae).

PubMed

Lavolpe, Mariano; Greco, Laura López; Kesselman, Daniela; Rodríguez, Enrique

2004-04-01

Ovigerous females of the estuarine crab Chasmagnathus granulatus were exposed to copper (0.01 and 1 mg/L), zinc (0.05, 1, and 10 mg/L), or lead (0.01 and 1 mg/L) during early, late, or whole embryonic development. None of the assayed heavy metals produced a significant mortality of females, neither a decrease in the number of hatched larvae nor a decrease in the egg incubation time, but several morphological abnormalities were detected in hatched larvae. The abnormalities were classified in three categories: eye, body pigmentary, and body morphological abnormalities. Those larvae with eye and body pigmentary abnormalities, particularly those involving retinal pigments and chromatophores, showed the highest incidence by exposure to the assayed metals. In addition, embryos were more susceptible to copper and zinc during the late period of development, whereas the effect of lead was greater during the early period of embryogenesis. Some teratogenic effects observed in C. granulatus embryos exposed to heavy metals, particularly the hypertrophy and hypopigmentation of eyes observed in the laboratory at a lead concentration as low as that reported for the natural environment, could be considered as sensitive biomarkers for this kind of pollutant.

Bilateral Coats' Disease Combined with Retinopathy of Prematurity

PubMed Central

Gursoy, Huseyin; Erol, Nazmiye; Bilgec, Mustafa Deger; Basmak, Hikmet; Kutlay, Ozden; Aslan, Huseyin

2015-01-01

Purpose. To report a case of bilateral Coats' disease combined with retinopathy of prematurity (ROP). Case. Retinal vascularization was complete in the right eye, whereas zone III, stage 3 ROP and preplus disease were observed in the left eye at 43 weeks of postmenstrual age (PMA) in a 31-week premature, 1200-g neonate. Intraretinal exudates developed and retinal hemorrhages increased in the left eye at 51 weeks of PMA. Diode laser photocoagulation (LP) was applied to the left eye. Exudates involved the macula, and telangiectatic changes developed one month following LP. Additional LP was applied to the left eye combined with intravitreal bevacizumab (IVB) injection at 55 weeks of PMA. Disease regressed one month after the additional therapy. At the 14-month examination of the baby, telangiectatic changes and intraretinal exudates were observed in the right eye. Diode LP was applied to the right eye combined with IVB injection. Exudates did not resolve completely, and cryotherapy was applied one month following LP. Retinal findings regressed three months following the cryotherapy. Conclusion. This is the first report of presumed bilateral Coats' disease combined with ROP. If Coats' disease could be diagnosed at early stages, it would be a disease associated with better prognosis. PMID:26413362

The Nedd4 binding protein 3 is required for anterior neural development in Xenopus laevis.

PubMed

Kiem, Lena-Maria; Dietmann, Petra; Linnemann, Alexander; Schmeisser, Michael J; Kühl, Susanne J

2017-03-01

The Fezzin family member Nedd4-binding protein 3 (N4BP3) is known to regulate axonal and dendritic branching. Here, we show that n4bp3 is expressed in the neural tissue of the early Xenopus laevis embryo including the eye, the brain and neural crest cells. Knockdown of N4bp3 in the Xenopus anterior neural tissue results in severe developmental impairment of the eye, the brain and neural crest derived cranial cartilage structures. Moreover, we demonstrate that N4bp3 depletion leads to a significant reduction of both eye and brain specific marker genes and reduced neural crest cell migration. Finally, we demonstrate an impact of N4bp3 deficiency on cell apoptosis and proliferation. Our studies indicate that N4bp3 is required for early anterior neural development of vertebrates. This is in line with a study implicating that genetic disruption of N4BP3 in humans might be related to neurodevelopmental disease. Copyright © 2017 Elsevier Inc. All rights reserved.

A Homolog of Subtilisin-Like Proprotein Convertase 7 Is Essential to Anterior Neural Development in Xenopus

PubMed Central

Senturker, Sema; Thomas, John Terrig; Mateshaytis, Jennifer; Moos, Malcolm

2012-01-01

Background Subtilisin-like Proprotein Convertase 7 (SPC7) is a member of the subtilisin/kexin family of pro-protein convertases. It cleaves many pro-proteins to release their active proteins, including members of the bone morphogenetic protein (BMP) family of signaling molecules. Other SPCs are known to be required during embryonic development but corresponding data regarding SPC7 have not been reported previously. Methodology/Principal Findings We demonstrated that Xenopus SPC7 (SPC7) was expressed predominantly in the developing brain and eye, throughout the neural plate initially, then more specifically in the lens and retina primordia as development progressed. Since no prior functional information has been reported for SPC7, we used gain- and loss-of-function experiments to investigate the possibility that it may also convey patterning or tissue specification information similarly to Furin, SPC4, and SPC6. Overexpression of SPC7 was without effect. In contrast, injection of SPC7 antisense morpholino oligonucleotides (MO) into a single blastomere at the 2- or 4-cell stage produced marked disruption of head structures; anophthalmia was salient. Bilateral injections suppressed head and eye formation completely. In parallel with suppression of eye and brain development by SPC7 knockdown, expression of early anterior neural markers (Sox2, Otx2, Rx2, and Pax6) and late eye-specific markers (β-Crystallin and Opsin), and of BMP target genes such as Tbx2 and Tbx3, was reduced or eliminated. Taken together, these findings suggest a critical role for SPC7–perhaps, at least in part, due to activation of one or more BMPs–in early patterning of the anterior neural plate and its derivatives. Conclusion/Significance SPC7 is required for normal development of the eye and brain, possibly through processing BMPs, though other potential substrates cannot be excluded. PMID:22761776

Outcome of retinopathy in chronic hepatitis C patients treated with peginterferon and ribavirin.

PubMed

Mehta, Nilesh; Murthy, Uma K; Kaul, Vivek; Alpert, Samuel; Abruzzese, Gerald; Teitelbaum, Charles

2010-02-01

The purpose of this study is to evaluate the incidence and outcome of retinopathy in chronic hepatitis C patients treated with peginterferon and ribavirin. A total of 74 hepatitis C patients with baseline eye exams and eye exams during therapy were included. Retinopathy was defined as development of cotton wool spots and/or intra-retinal hemorrhage. Demographics, hepatitis C viral characteristics, treatment and laboratory data, and eye exam findings were compared in groups with and without retinopathy. Retinopathy developed in 28 (38%), early in therapy. Pre-treatment eye exams did not predict risk of retinopathy. Therapy was continued in all but one; cotton wool spots resolved in 24 of 26. All nine patients with intra-retinal hemorrhage had resolution. No patient had retinopathy-related visual deterioration. Retinopathy is common with peginterferon therapy, but the outcome is favorable. Cessation of therapy for retinopathy is not warranted. Severe visual disturbances and scotomas deserve further evaluation.

dlx and sp6-9 Control Optic Cup Regeneration in a Prototypic Eye

PubMed Central

Lapan, Sylvain W.; Reddien, Peter W.

2011-01-01

Optic cups are a structural feature of diverse eyes, from simple pit eyes to camera eyes of vertebrates and cephalopods. We used the planarian prototypic eye as a model to study the genetic control of optic cup formation and regeneration. We identified two genes encoding transcription factors, sp6-9 and dlx, that were expressed in the eye specifically in the optic cup and not the photoreceptor neurons. RNAi of these genes prevented formation of visible optic cups during regeneration. Planarian regeneration requires an adult proliferative cell population with stem cell-like properties called the neoblasts. We found that optic cup formation occurred only after migration of progressively differentiating progenitor cells from the neoblast population. The eye regeneration defect caused by dlx and sp6-9 RNAi can be explained by a failure to generate these early optic cup progenitors. Dlx and Sp6-9 genes function as a module during the development of diverse animal appendages, including vertebrate and insect limbs. Our work reveals a novel function for this gene pair in the development of a fundamental eye component, and it utilizes these genes to demonstrate a mechanism for total organ regeneration in which extensive cell movement separates new cell specification from organ morphogenesis. PMID:21852957

Short-latency primate vestibuloocular responses during translation

NASA Technical Reports Server (NTRS)

Angelaki, D. E.; McHenry, M. Q.

1999-01-01

Short-lasting, transient head displacements and near target fixation were used to measure the latency and early response gain of vestibularly evoked eye movements during lateral and fore-aft translations in rhesus monkeys. The latency of the horizontal eye movements elicited during lateral motion was 11.9 +/- 5.4 ms. Viewing distance-dependent behavior was seen as early as the beginning of the response profile. For fore-aft motion, latencies were different for forward and backward displacements. Latency averaged 7.1 +/- 9.3 ms during forward motion (same for both eyes) and 12.5 +/- 6.3 ms for the adducting eye (e.g., left eye during right fixation) during backward motion. Latencies during backward motion were significantly longer for the abducting eye (18.9 +/- 9.8 ms). Initial acceleration gains of the two eyes were generally larger than unity but asymmetric. Specifically, gains were consistently larger for abducting than adducting eye movements. The large initial acceleration gains tended to compensate for the response latencies such that the early eye movement response approached, albeit consistently incompletely, that required for maintaining visual acuity during the movement. These short-latency vestibuloocular responses could complement the visually generated optic flow responses that have been shown to exhibit much longer latencies.

Screening for Dyslexia Using Eye Tracking during Reading.

PubMed

Nilsson Benfatto, Mattias; Öqvist Seimyr, Gustaf; Ygge, Jan; Pansell, Tony; Rydberg, Agneta; Jacobson, Christer

2016-01-01

Dyslexia is a neurodevelopmental reading disability estimated to affect 5-10% of the population. While there is yet no full understanding of the cause of dyslexia, or agreement on its precise definition, it is certain that many individuals suffer persistent problems in learning to read for no apparent reason. Although it is generally agreed that early intervention is the best form of support for children with dyslexia, there is still a lack of efficient and objective means to help identify those at risk during the early years of school. Here we show that it is possible to identify 9-10 year old individuals at risk of persistent reading difficulties by using eye tracking during reading to probe the processes that underlie reading ability. In contrast to current screening methods, which rely on oral or written tests, eye tracking does not depend on the subject to produce some overt verbal response and thus provides a natural means to objectively assess the reading process as it unfolds in real-time. Our study is based on a sample of 97 high-risk subjects with early identified word decoding difficulties and a control group of 88 low-risk subjects. These subjects were selected from a larger population of 2165 school children attending second grade. Using predictive modeling and statistical resampling techniques, we develop classification models from eye tracking records less than one minute in duration and show that the models are able to differentiate high-risk subjects from low-risk subjects with high accuracy. Although dyslexia is fundamentally a language-based learning disability, our results suggest that eye movements in reading can be highly predictive of individual reading ability and that eye tracking can be an efficient means to identify children at risk of long-term reading difficulties.

Acquired color vision and visual field defects in patients with ocular hypertension and early glaucoma

PubMed Central

Papaconstantinou, Dimitris; Georgalas, Ilias; Kalantzis, George; Karmiris, Efthimios; Koutsandrea, Chrysanthi; Diagourtas, Andreas; Ladas, Ioannis; Georgopoulos, Gerasimos

2009-01-01

Purpose: To study acquired color vision and visual field defects in patients with ocular hypertension (OH) and early glaucoma. Methods: In a prospective study we evaluated 99 eyes of 56 patients with OH without visual field defects and no hereditary color deficiencies, followed up for 4 to 6 years (mean = 4.7 ± 0.6 years). Color vision defects were studied using a special computer program for Farnsworth–Munsell 100 hue test and visual field tests were performed with Humphrey analyzer using program 30–2. Both tests were repeated every six months. Results: In fifty-six eyes, glaucomatous defects were observed during the follow-up period. There was a statistically significant difference in total error score (TES) between eyes that eventually developed glaucoma (157.89 ± 31.79) and OH eyes (75.51 ± 31.57) at the first examination (t value 12.816, p < 0.001). At the same time visual field indices were within normal limits in both groups. In the glaucomatous eyes the earliest statistical significant change in TES was identified at the first year of follow-up and was −20.62 ± 2.75 (t value 9.08, p < 0.001) while in OH eyes was −2.11 ± 4.36 (t value 1.1, p = 0.276). Pearson’s coefficient was high in all examinations and showed a direct correlation between TES and mean deviation and corrected pattern standard deviation in both groups. Conclusion: Quantitative analysis of color vision defects provides the possibility of follow-up and can prove a useful means for detecting early glaucomatous changes in patients with normal visual fields. PMID:19668575

Recognizing Cataracts

MedlinePlus

... age-related cataract. They recommend eating plenty of green leafy vegetables, fruits, nuts and other healthy foods. Also, don’t smoke, because smoking may speed cataract development. To screen for early signs of eye disease, Bishop recommends ...

Eye Diseases

MedlinePlus

... the back of the eye Macular degeneration - a disease that destroys sharp, central vision Diabetic eye problems ... defense is to have regular checkups, because eye diseases do not always have symptoms. Early detection and ...

Analysis of Pax6 contiguous gene deletions in the mouse, Mus musculus, identifies regions distinct from Pax6 responsible for extreme small-eye and belly-spotting phenotypes.

PubMed

Favor, Jack; Bradley, Alan; Conte, Nathalie; Janik, Dirk; Pretsch, Walter; Reitmeir, Peter; Rosemann, Michael; Schmahl, Wolfgang; Wienberg, Johannes; Zaus, Irmgard

2009-08-01

In the mouse Pax6 function is critical in a dose-dependent manner for proper eye development. Pax6 contiguous gene deletions were shown to be homozygous lethal at an early embryonic stage. Heterozygotes express belly spotting and extreme microphthalmia. The eye phenotype is more severe than in heterozygous Pax6 intragenic null mutants, raising the possibility that deletions are functionally different from intragenic null mutations or that a region distinct from Pax6 included in the deletions affects eye phenotype. We recovered and identified the exact regions deleted in three new Pax6 deletions. All are homozygous lethal at an early embryonic stage. None express belly spotting. One expresses extreme microphthalmia and two express the milder eye phenotype similar to Pax6 intragenic null mutants. Analysis of Pax6 expression levels and the major isoforms excluded the hypothesis that the deletions expressing extreme microphthalmia are directly due to the action of Pax6 and functionally different from intragenic null mutations. A region distinct from Pax6 containing eight genes was identified for belly spotting. A second region containing one gene (Rcn1) was identified for the extreme microphthalmia phenotype. Rcn1 is a Ca(+2)-binding protein, resident in the endoplasmic reticulum, participates in the secretory pathway and expressed in the eye. Our results suggest that deletion of Rcn1 directly or indirectly contributes to the eye phenotype in Pax6 contiguous gene deletions.

ENLARGEMENT OF FOVEAL AVASCULAR ZONE IN DIABETIC EYES EVALUATED BY EN FACE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PubMed

Takase, Noriaki; Nozaki, Miho; Kato, Aki; Ozeki, Hironori; Yoshida, Munenori; Ogura, Yuichiro

2015-11-01

To evaluate the area of the foveal avascular zone (FAZ) detected by en face OCTA (AngioVue, Avanti OCT; Optovue) in healthy and diabetic eyes. Retrospective chart review of patients who underwent fundus examination including en face OCTA. Eyes with proliferative diabetic retinopathy and history of laser photocoagulation were excluded. The FAZ area in the superficial and deep plexus layers were measured and evaluated using ImageJ software. The FAZ area in the superficial layer was 0.25 ± 0.06 mm² in healthy eyes (n = 19), whereas it was 0.37 ± 0.07 mm² in diabetic eyes without retinopathy (n = 24) and 0.38 ± 0.11 mm² in eyes with diabetic retinopathy (n = 20). Diabetic eyes showed statistically significant FAZ enlargement compared with healthy eyes, regardless of the presence of retinopathy (P < 0.01). The FAZ area in the deep plexus layer was also significantly larger in diabetic eyes than in healthy eyes (P < 0.01). Our data suggest that diabetic eyes show retinal microcirculation impairment in the macula even before retinopathy develops. En face OCTA is a useful noninvasive screening tool for detecting early microcirculatory disturbance in patients with diabetes.

Development and origins of zebrafish ocular vasculature.

PubMed

Kaufman, Rivka; Weiss, Omri; Sebbagh, Meyrav; Ravid, Revital; Gibbs-Bar, Liron; Yaniv, Karina; Inbal, Adi

2015-03-27

The developing eye receives blood supply from two vascular systems, the intraocular hyaloid system and the superficial choroidal vessels. In zebrafish, a highly stereotypic and simple set of vessels develops on the surface of the eye prior to development of choroidal vessels. The origins and formation of this so-called superficial system have not been described. We have analyzed the development of superficial vessels by time-lapse imaging and identified their origins by photoconversion experiments in kdrl:Kaede transgenic embryos. We show that the entire superficial system is derived from a venous origin, and surprisingly, we find that the hyaloid system has, in addition to its previously described arterial origin, a venous origin for specific vessels. Despite arising solely from a vein, one of the vessels in the superficial system, the nasal radial vessel (NRV), appears to acquire an arterial identity while growing over the nasal aspect of the eye and this happens in a blood flow-independent manner. Our results provide a thorough analysis of the early development and origins of zebrafish ocular vessels and establish the superficial vasculature as a model for studying vascular patterning in the context of the developing eye.

Conserved genetic pathways associated with microphthalmia, anophthalmia, and coloboma

PubMed Central

Reis, Linda M.; Semina, Elena V.

2016-01-01

The human eye is a complex organ whose development requires extraordinary coordination of developmental processes. The conservation of ocular developmental steps in vertebrates suggests possible common genetic mechanisms. Genetic diseases involving the eye represent a leading cause of blindness in children and adults. During the last decades, there has been an exponential increase in genetic studies of ocular disorders. In this review, we summarize current success in identification of genes responsible for microphthalmia, anophthalmia and coloboma (MAC) phenotypes, which are associated with early defects in embryonic eye development. Studies in animal models for the orthologous genes identified overlapping phenotypes for most factors confirming the conservation of their function in vertebrate development. These animal models allow for further investigation of the mechanisms of MAC, integration of various identified genes into common developmental pathways and, finally, provide an avenue for the development and testing of therapeutic interventions. PMID:26046913

Conserved genetic pathways associated with microphthalmia, anophthalmia, and coloboma.

PubMed

Reis, Linda M; Semina, Elena V

2015-06-01

The human eye is a complex organ whose development requires extraordinary coordination of developmental processes. The conservation of ocular developmental steps in vertebrates suggests possible common genetic mechanisms. Genetic diseases involving the eye represent a leading cause of blindness in children and adults. During the last decades, there has been an exponential increase in genetic studies of ocular disorders. In this review, we summarize current success in identification of genes responsible for microphthalmia, anophthalmia, and coloboma (MAC) phenotypes, which are associated with early defects in embryonic eye development. Studies in animal models for the orthologous genes identified overlapping phenotypes for most factors, confirming the conservation of their function in vertebrate development. These animal models allow for further investigation of the mechanisms of MAC, integration of various identified genes into common developmental pathways and finally, provide an avenue for the development and testing of therapeutic interventions. © 2015 Wiley Periodicals, Inc.

Goji

MedlinePlus

... people who are not taking medicine for diabetes. Dry eyes. Early research shows that using eye drops and ... ingredients for one month can improve symptoms of dry eyes better than using eye drops alone. It's not ...

Early Detection Rapid Response Program Targets New Noxious Weed Species in Washington State

ERIC Educational Resources Information Center

Andreas, Jennifer E.; Halpern, Alison D.; DesCamp, Wendy C.; Miller, Timothy W.

2015-01-01

Early detection, rapid response is a critical component of invasive plant management. It can be challenging, however, to detect new invaders before they become established if landowners cannot identify species of concern. In order to increase awareness, eye-catching postcards were developed in Washington State as part of a noxious weed educational…

Incidence of secondary glaucoma in behcet disease.

PubMed

Elgin, Ufuk; Berker, Nilufer; Batman, Aygen

2004-12-01

To determine the incidence of secondary glaucoma in Behcet disease. A total of 230 eyes of 129 patients with Behcet disease, were examined in uveitis and glaucoma clinics of Ankara Social Security Eye Hospital between January 1997 and September 2002. The data from all patients were investigated both retrospectively and prospectively. The mean age of 129 patients was 34.2 +/- 7.4 years (range, 18 to 55 years). In 22 patients (17%), the disease was diagnosed on the basis of the ocular findings, while in the remaining 107 patients (83%), the period between the diagnosis of Behcet disease and the onset of the ocular symptoms was 23.3 +/- 17 months (range, 1 month to 5.3 years); 122 eyes (53%) had the episodes of acute recurrent iridocyclitis, while 108 eyes (47%) developed chronic posterior uveitis, including vitreitis, retinitis, vasculitis, or optic nerve involvement. Secondary glaucoma was diagnosed in 25 eyes (10.9%); 11 eyes (44%) with steroid or inflammation induced open angle glaucoma, 6 eyes (24%) with partial angle-closure glaucoma and peripheral anterior synechiae, 5 eyes (20%) with angle closure glaucoma, peripheral anterior synechiae, and pupil block and 3 eyes (12%) with neovascular glaucoma. The treatments included YAG-laser iridotomy in 5 eyes, diode-laser cyclodestruction in 3 eyes, primary trabeculectomies with mitomycin-c in 4 eyes, secondary trabeculectomies with mitomycin-c in 2 eyes, Ahmed valve implantations in 2 eyes, and cyclocryotherapy in 3 eyes. We suggest that secondary glaucoma is a common and serious complication of Behcet disease. It develops as a result of multiple factors, generally triggered by recurrent intraocular inflammation. Early recognition and treatment of these factors have vital importance to avoid the visual morbidity.

Vocabulary Development and Language Learning

ERIC Educational Resources Information Center

Strickland, Ruth G.

1972-01-01

Teachers, through raising their eyes from textbooks and looking at living language as it influences the lives of individual people and the course of human events, can help children preserve their early zest for language. (Author)

Basal ganglia dysfunction in idiopathic REM sleep behaviour disorder parallels that in early Parkinson's disease.

PubMed

Rolinski, Michal; Griffanti, Ludovica; Piccini, Paola; Roussakis, Andreas A; Szewczyk-Krolikowski, Konrad; Menke, Ricarda A; Quinnell, Timothy; Zaiwalla, Zenobia; Klein, Johannes C; Mackay, Clare E; Hu, Michele T M

2016-08-01

SEE POSTUMA DOI101093/AWW131 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Resting state functional magnetic resonance imaging dysfunction within the basal ganglia network is a feature of early Parkinson's disease and may be a diagnostic biomarker of basal ganglia dysfunction. Currently, it is unclear whether these changes are present in so-called idiopathic rapid eye movement sleep behaviour disorder, a condition associated with a high rate of future conversion to Parkinson's disease. In this study, we explore the utility of resting state functional magnetic resonance imaging to detect basal ganglia network dysfunction in rapid eye movement sleep behaviour disorder. We compare these data to a set of healthy control subjects, and to a set of patients with established early Parkinson's disease. Furthermore, we explore the relationship between resting state functional magnetic resonance imaging basal ganglia network dysfunction and loss of dopaminergic neurons assessed with dopamine transporter single photon emission computerized tomography, and perform morphometric analyses to assess grey matter loss. Twenty-six patients with polysomnographically-established rapid eye movement sleep behaviour disorder, 48 patients with Parkinson's disease and 23 healthy control subjects were included in this study. Resting state networks were isolated from task-free functional magnetic resonance imaging data using dual regression with a template derived from a separate cohort of 80 elderly healthy control participants. Resting state functional magnetic resonance imaging parameter estimates were extracted from the study subjects in the basal ganglia network. In addition, eight patients with rapid eye movement sleep behaviour disorder, 10 with Parkinson's disease and 10 control subjects received (123)I-ioflupane single photon emission computerized tomography. We tested for reduction of basal ganglia network connectivity, and for loss of tracer uptake in rapid eye movement sleep behaviour disorder and Parkinson's disease relative to each other and to controls. Connectivity measures of basal ganglia network dysfunction differentiated both rapid eye movement sleep behaviour disorder and Parkinson's disease from controls with high sensitivity (96%) and specificity (74% for rapid eye movement sleep behaviour disorder, 78% for Parkinson's disease), indicating its potential as an indicator of early basal ganglia dysfunction. Rapid eye movement sleep behaviour disorder was indistinguishable from Parkinson's disease on resting state functional magnetic resonance imaging despite obvious differences on dopamine transported single photon emission computerized tomography. Basal ganglia connectivity is a promising biomarker for the detection of early basal ganglia network dysfunction, and may help to identify patients at risk of developing Parkinson's disease in the future. Future risk stratification using a polymodal approach could combine basal ganglia network connectivity with clinical and other imaging measures, with important implications for future neuroprotective trials in rapid eye movement sleep behaviour disorder. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.

Basal ganglia dysfunction in idiopathic REM sleep behaviour disorder parallels that in early Parkinson’s disease

PubMed Central

Rolinski, Michal; Griffanti, Ludovica; Piccini, Paola; Roussakis, Andreas A.; Szewczyk-Krolikowski, Konrad; Menke, Ricarda A.; Quinnell, Timothy; Zaiwalla, Zenobia; Klein, Johannes C.; Mackay, Clare E.

2016-01-01

Abstract See Postuma (doi:10.1093/aww131) for a scientific commentary on this article. Resting state functional magnetic resonance imaging dysfunction within the basal ganglia network is a feature of early Parkinson’s disease and may be a diagnostic biomarker of basal ganglia dysfunction. Currently, it is unclear whether these changes are present in so-called idiopathic rapid eye movement sleep behaviour disorder, a condition associated with a high rate of future conversion to Parkinson’s disease. In this study, we explore the utility of resting state functional magnetic resonance imaging to detect basal ganglia network dysfunction in rapid eye movement sleep behaviour disorder. We compare these data to a set of healthy control subjects, and to a set of patients with established early Parkinson’s disease. Furthermore, we explore the relationship between resting state functional magnetic resonance imaging basal ganglia network dysfunction and loss of dopaminergic neurons assessed with dopamine transporter single photon emission computerized tomography, and perform morphometric analyses to assess grey matter loss. Twenty-six patients with polysomnographically-established rapid eye movement sleep behaviour disorder, 48 patients with Parkinson’s disease and 23 healthy control subjects were included in this study. Resting state networks were isolated from task-free functional magnetic resonance imaging data using dual regression with a template derived from a separate cohort of 80 elderly healthy control participants. Resting state functional magnetic resonance imaging parameter estimates were extracted from the study subjects in the basal ganglia network. In addition, eight patients with rapid eye movement sleep behaviour disorder, 10 with Parkinson’s disease and 10 control subjects received 123I-ioflupane single photon emission computerized tomography. We tested for reduction of basal ganglia network connectivity, and for loss of tracer uptake in rapid eye movement sleep behaviour disorder and Parkinson’s disease relative to each other and to controls. Connectivity measures of basal ganglia network dysfunction differentiated both rapid eye movement sleep behaviour disorder and Parkinson’s disease from controls with high sensitivity (96%) and specificity (74% for rapid eye movement sleep behaviour disorder, 78% for Parkinson’s disease), indicating its potential as an indicator of early basal ganglia dysfunction. Rapid eye movement sleep behaviour disorder was indistinguishable from Parkinson’s disease on resting state functional magnetic resonance imaging despite obvious differences on dopamine transported single photon emission computerized tomography. Basal ganglia connectivity is a promising biomarker for the detection of early basal ganglia network dysfunction, and may help to identify patients at risk of developing Parkinson’s disease in the future. Future risk stratification using a polymodal approach could combine basal ganglia network connectivity with clinical and other imaging measures, with important implications for future neuroprotective trials in rapid eye movement sleep behaviour disorder. PMID:27297241

Eye movement analysis and cognitive processing: detecting indicators of conversion to Alzheimer’s disease

PubMed Central

Pereira, Marta LG Freitas; Camargo, Marina von Zuben A; Aprahamian, Ivan; Forlenza, Orestes V

2014-01-01

A great amount of research has been developed around the early cognitive impairments that best predict the onset of Alzheimer’s disease (AD). Given that mild cognitive impairment (MCI) is no longer considered to be an intermediate state between normal aging and AD, new paths have been traced to acquire further knowledge about this condition and its subtypes, and to determine which of them have a higher risk of conversion to AD. It is now known that other deficits besides episodic and semantic memory impairments may be present in the early stages of AD, such as visuospatial and executive function deficits. Furthermore, recent investigations have proven that the hippocampus and the medial temporal lobe structures are not only involved in memory functioning, but also in visual processes. These early changes in memory, visual, and executive processes may also be detected with the study of eye movement patterns in pathological conditions like MCI and AD. In the present review, we attempt to explore the existing literature concerning these patterns of oculomotor changes and how these changes are related to the early signs of AD. In particular, we argue that deficits in visual short-term memory, specifically in iconic memory, attention processes, and inhibitory control, may be found through the analysis of eye movement patterns, and we discuss how they might help to predict the progression from MCI to AD. We add that the study of eye movement patterns in these conditions, in combination with neuroimaging techniques and appropriate neuropsychological tasks based on rigorous concepts derived from cognitive psychology, may highlight the early presence of cognitive impairments in the course of the disease. PMID:25031536

Event-related potential and eye tracking evidence of the developmental dynamics of face processing.

PubMed

Meaux, Emilie; Hernandez, Nadia; Carteau-Martin, Isabelle; Martineau, Joëlle; Barthélémy, Catherine; Bonnet-Brilhault, Frédérique; Batty, Magali

2014-04-01

Although the wide neural network and specific processes related to faces have been revealed, the process by which face-processing ability develops remains unclear. An interest in faces appears early in infancy, and developmental findings to date have suggested a long maturation process of the mechanisms involved in face processing. These developmental changes may be supported by the acquisition of more efficient strategies to process faces (theory of expertise) and by the maturation of the face neural network identified in adults. This study aimed to clarify the link between event-related potential (ERP) development in response to faces and the behavioral changes in the way faces are scanned throughout childhood. Twenty-six young children (4-10 years of age) were included in two experimental paradigms, the first exploring ERPs during face processing, the second investigating the visual exploration of faces using an eye-tracking system. The results confirmed significant age-related changes in visual ERPs (P1, N170 and P2). Moreover, an increased interest in the eye region and an attentional shift from the mouth to the eyes were also revealed. The proportion of early fixations on the eye region was correlated with N170 and P2 characteristics, highlighting a link between the development of ERPs and gaze behavior. We suggest that these overall developmental dynamics may be sustained by a gradual, experience-dependent specialization in face processing (i.e. acquisition of face expertise), which produces a more automatic and efficient network associated with effortless identification of faces, and allows the emergence of human-specific social and communication skills. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Eye-tracking-based assessment of cognitive function in low-resource settings.

PubMed

Forssman, Linda; Ashorn, Per; Ashorn, Ulla; Maleta, Kenneth; Matchado, Andrew; Kortekangas, Emma; Leppänen, Jukka M

2017-04-01

Early development of neurocognitive functions in infants can be compromised by poverty, malnutrition and lack of adequate stimulation. Optimal management of neurodevelopmental problems in infants requires assessment tools that can be used early in life, and are objective and applicable across economic, cultural and educational settings. The present study examined the feasibility of infrared eye tracking as a novel and highly automated technique for assessing visual-orienting and sequence-learning abilities as well as attention to facial expressions in young (9-month-old) infants. Techniques piloted in a high-resource laboratory setting in Finland (N=39) were subsequently field-tested in a community health centre in rural Malawi (N=40). Parents' perception of the acceptability of the method (Finland 95%, Malawi 92%) and percentages of infants completing the whole eye-tracking test (Finland 95%, Malawi 90%) were high, and percentages of valid test trials (Finland 69-85%, Malawi 68-73%) satisfactory at both sites. Test completion rates were slightly higher for eye tracking (90%) than traditional observational tests (87%) in Malawi. The predicted response pattern indicative of specific cognitive function was replicated in Malawi, but Malawian infants exhibited lower response rates and slower processing speed across tasks. High test completion rates and the replication of the predicted test patterns in a novel environment in Malawi support the feasibility of eye tracking as a technique for assessing infant development in low-resource setting. Further research is needed to the test-retest stability and predictive validity of the eye-tracking scores in low-income settings. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Mfsd2a Is a Transporter for the Essential ω-3 Fatty Acid Docosahexaenoic Acid (DHA) in Eye and Is Important for Photoreceptor Cell Development*

PubMed Central

Wong, Bernice H.; Chan, Jia Pei; Cazenave-Gassiot, Amaury; Poh, Rebecca W.; Foo, Juat Chin; Galam, Dwight L. A.; Ghosh, Sujoy; Nguyen, Long N.; Barathi, Veluchamy A.; Yeo, Sia W.; Luu, Chi D.; Wenk, Markus R.; Silver, David L.

2016-01-01

Eye photoreceptor membrane discs in outer rod segments are highly enriched in the visual pigment rhodopsin and the ω-3 fatty acid docosahexaenoic acid (DHA). The eye acquires DHA from blood, but transporters for DHA uptake across the blood-retinal barrier or retinal pigment epithelium have not been identified. Mfsd2a is a newly described sodium-dependent lysophosphatidylcholine (LPC) symporter expressed at the blood-brain barrier that transports LPCs containing DHA and other long-chain fatty acids. LPC transport via Mfsd2a has been shown to be necessary for human brain growth. Here we demonstrate that Mfsd2a is highly expressed in retinal pigment epithelium in embryonic eye, before the development of photoreceptors, and is the primary site of Mfsd2a expression in the eye. Eyes from whole body Mfsd2a-deficient (KO) mice, but not endothelium-specific Mfsd2a-deficient mice, were DHA-deficient and had significantly reduced LPC/DHA transport in vivo. Fluorescein angiography indicated normal blood-retinal barrier function. Histological and electron microscopic analysis indicated that Mfsd2a KO mice exhibited a specific reduction in outer rod segment length, disorganized outer rod segment discs, and mislocalization of and reduction in rhodopsin early in postnatal development without loss of photoreceptors. Minor photoreceptor cell loss occurred in adult Mfsd2a KO mice, but electroretinography indicated visual function was normal. The developing eyes of Mfsd2a KO mice had activated microglia and up-regulation of lipogenic and cholesterogenic genes, likely adaptations to loss of LPC transport. These findings identify LPC transport via Mfsd2a as an important pathway for DHA uptake in eye and for development of photoreceptor membrane discs. PMID:27008858

Spatial updating depends on gaze direction even after loss of vision.

PubMed

Reuschel, Johanna; Rösler, Frank; Henriques, Denise Y P; Fiehler, Katja

2012-02-15

Direction of gaze (eye angle + head angle) has been shown to be important for representing space for action, implying a crucial role of vision for spatial updating. However, blind people have no access to vision yet are able to perform goal-directed actions successfully. Here, we investigated the role of visual experience for localizing and updating targets as a function of intervening gaze shifts in humans. People who differed in visual experience (late blind, congenitally blind, or sighted) were briefly presented with a proprioceptive reach target while facing it. Before they reached to the target's remembered location, they turned their head toward an eccentric direction that also induced corresponding eye movements in sighted and late blind individuals. We found that reaching errors varied systematically as a function of shift in gaze direction only in participants with early visual experience (sighted and late blind). In the late blind, this effect was solely present in people with moveable eyes but not in people with at least one glass eye. Our results suggest that the effect of gaze shifts on spatial updating develops on the basis of visual experience early in life and remains even after loss of vision as long as feedback from the eyes and head is available.

Arthropod eyes: The early Cambrian fossil record and divergent evolution of visual systems.

PubMed

Strausfeld, Nicholas J; Ma, Xiaoya; Edgecombe, Gregory D; Fortey, Richard A; Land, Michael F; Liu, Yu; Cong, Peiyun; Hou, Xianguang

2016-03-01

Four types of eyes serve the visual neuropils of extant arthropods: compound retinas composed of adjacent facets; a visual surface populated by spaced eyelets; a smooth transparent cuticle providing inwardly directed lens cylinders; and single-lens eyes. The first type is a characteristic of pancrustaceans, the eyes of which comprise lenses arranged as hexagonal or rectilinear arrays, each lens crowning 8-9 photoreceptor neurons. Except for Scutigeromorpha, the second type typifies Myriapoda whose relatively large eyelets surmount numerous photoreceptive rhabdoms stacked together as tiers. Scutigeromorph eyes are facetted, each lens crowning some dozen photoreceptor neurons of a modified apposition-type eye. Extant chelicerate eyes are single-lensed except in xiphosurans, whose lateral eyes comprise a cuticle with a smooth outer surface and an inner one providing regular arrays of lens cylinders. This account discusses whether these disparate eye types speak for or against divergence from one ancestral eye type. Previous considerations of eye evolution, focusing on the eyes of trilobites and on facet proliferation in xiphosurans and myriapods, have proposed that the mode of development of eyes in those taxa is distinct from that of pancrustaceans and is the plesiomorphic condition from which facetted eyes have evolved. But the recent discovery of enormous regularly facetted compound eyes belonging to early Cambrian radiodontans suggests that high-resolution facetted eyes with superior optics may be the ground pattern organization for arthropods, predating the evolution of arthrodization and jointed post-protocerebral appendages. Here we provide evidence that compound eye organization in stem-group euarthropods of the Cambrian can be understood in terms of eye morphologies diverging from this ancestral radiodontan-type ground pattern. We show that in certain Cambrian groups apposition eyes relate to fixed or mobile eyestalks, whereas other groups reveal concomitant evolution of sessile eyes equipped with optics typical of extant xiphosurans. Observations of fossil material, including that of trilobites and eurypterids, support the proposition that the ancestral compound eye was the apposition type. Cambrian arthropods include possible precursors of mandibulate eyes. The latter are the modified compound eyes, now sessile, and their underlying optic lobes exemplified by scutigeromorph chilopods, and the mobile stalked compound eyes and more elaborate optic lobes typifying Pancrustacea. Radical divergence from an ancestral apposition type is demonstrated by the evolution of chelicerate eyes, from doublet sessile-eyed stem-group taxa to special apposition eyes of xiphosurans, the compound eyes of eurypterids, and single-lens eyes of arachnids. Different eye types are discussed with respect to possible modes of life of the extinct species that possessed them, comparing these to extant counterparts and the types of visual centers the eyes might have served. Copyright © 2015 Elsevier Ltd. All rights reserved.

Visual Impairment in Infants and Young Children.

ERIC Educational Resources Information Center

Teplin, Stuart W.

1995-01-01

This article reviews the structure, development, function, and assessment of the visual system and then considers: common eye problems of young children with visual impairment; impacts of severe impairment on child development; and the roles of early intervention professionals, ophthalmologists, and pediatricians in working with these children and…

[Color vision impairment in workers exposed to mercury vapor].

PubMed

Jedrejko, Marta; Skoczyńska, Anna

2011-01-01

Acquired reversible dyschromatopsia has been associated with occupational exposure to mercury vapor. Early-detected impairments in color discrimination precede adverse permanent effects of mercury, so they may help to monitor the health of the exposed workers. The aim of this study was to evaluate the color discrimination ability in this group of workers, using Lanthony D-15d test. Employed in a chloralkali plant, 27 male workers exposed to mercury vapor and 27 healthy white-collar workers (control group) were qualified for the study. To assess color discrimination, the Lanthony 15-Hue desaturated test (Lanthony D-15) was used. In order to investigate quantitative and qualitative results, the Lanthony D-15d scoring software was performed. Urinary mercury was determined using flameless atomic absorption spectrometry. In the workers exposed to mercury vapor, urine mercury concentration was 117.4 +/- 62.6 microg/g creatinine on average compared with 0.279 +/- 0.224 mg/g creatinine in the control group (p < 0.0001). In 18 exposed persons (66.7%), the results of the Lanthony D-15d test showed qualitative changes, which are borderline corresponding to the early stage of developing dyschromatopsia type III. The quantitative analysis of the test findings indicated a significantly higher value of the Color Confusion Index (CCI) in the right eye in the exposed group compared to the control group (p = 0.01), with no significant difference in the CCI in the left eye. In the exposed group, the CCI in the right eye was significantly higher than the CCI in the left eye (p = 0.0005). There was neither correlation between CCI and the level of urinary mercury, nor between CCI and duration of exposure. The results showed that the Lanthony D-15d test is useful in the detection of early toxic effects in the eyesight of the workers exposed to mercury vapor. The observed color vision impairments are borderline corresponding to the early stage of developing dyschromatopsia type III.

Recent perspectives on the delivery of biologics to back of the eye

PubMed Central

Joseph, Mary; Trinh, Hoang M.; Cholkar, Kishore; Pal, Dhananjay; Mitra, Ashim K.

2017-01-01

Introduction Biologics are generally macromolecules, large in size with poor stability in biological environments. Delivery of biologics to tissues at the back of the eye remains a challenge. To overcome these challenges and treat posterior ocular diseases, several novel approaches have been developed. Nanotechnology-based delivery systems, like drug encapsulation technology, macromolecule implants and gene delivery are under investigation. We provide an overview of emerging technologies for biologics delivery to back of the eye tissues. Moreover, new biologic drugs currently in clinical trials for ocular neovascular diseases have been discussed. Areas Covered Anatomy of the eye, posterior segment disease and diagnosis, barriers to biologic delivery, ocular pharmacokinetic, novel biologic delivery system Expert Opinion Anti-VEGF therapy represents a significant advance in developing biologics for the treatment of ocular neovascular diseases. Various strategies for biologic delivery to posterior ocular tissues are under development with some in early or late stages of clinical trials. Despite significant progress in the delivery of biologics, there is unmet need to develop sustained delivery of biologics with nearly zero-order release kinetics to the back of the eye tissues. In addition, elevated intraocular pressure associated with frequent intravitreal injections of macromolecules is another concern that needs to be addressed. PMID:27573097

Feasibility of Undertaking Off-Site Infant Eye-Tracking Assessments of Neuro-Cognitive Functioning in Early-Intervention Centres

ERIC Educational Resources Information Center

Ballieux, Haiko; Tomalski, Przemyslaw; Kushnerneko, Elena; Johnson, Mark H.; Karmiloff-Smith, Annette; Moore, Derek G.

2016-01-01

Recent work suggests that differences in functional brain development are already identifiable in 6- to 9-month-old infants from low socio-economic status (SES) backgrounds. Investigation of early SES-related differences in neuro-cognitive functioning requires the recruitment of large and diverse samples of infants, yet it is often difficult to…

Corneal polarimetry after LASIK refractive surgery

NASA Astrophysics Data System (ADS)

Bueno, Juan M.; Berrio, Esther; Artal, Pablo

2006-01-01

Imaging polarimetry provides spatially resolved information on the polarization properties of a system. In the case of the living human eye, polarization could be related to the corneal biomechanical properties, which vary from the normal state as a result of surgery or pathologies. We have used an aberro-polariscope, which we recently developed, to determine and to compare the spatially resolved maps of polarization parameters across the pupil between normal healthy and post-LASIK eyes. The depolarization distribution is not uniform across the pupil, with post-surgery eyes presenting larger levels of depolarization. While retardation increases along the radius in normal eyes, this pattern becomes irregular after LASIK refractive surgery. The maps of slow axis also differ in normal and post-surgery eyes, with a larger disorder in post-LASIK eyes. Since these changes in polarization indicate subtle structural modifications of the cornea, this approach can be useful in a clinical environment to follow the biomechanical and optical changes of the cornea after refractive surgery or for the early diagnosis of different corneal pathologies.

Factors associated with early detection of choroidal neovascularization in age-related macular degeneration in the clinic setting.

PubMed

Lichtinger, Alejandro; Caraza, Mauricio; Galbinur, Tural; Chowers, Itay

2012-06-01

Delayed diagnosis of choroidal neovas cularization (CNV) in age-related macular degeneration (AMD) adversely affects visual outcome. To identify factors associated with early detection of CNV in the clinic setting. Demographic and clinical data and lesion characteristics were retrospectively collected from 76 consecutive AMD patients who had a history of CNV in one eye and presented with CNV in the second eye. These data were evaluated for association with visual acuity (VA) at the time of presentation. Better VA was associated with a history of CNV in the fellow eye (P < 0.0001), adherence to follow-up every 4 months (P = 0.015), younger age (P = 0.03), smaller lesion (P < 0.0001), and non-subfoveal location (P = 0.048). VA of the fellow eye did not correlate with VA at presentation with CNV. These data suggest that patients' experience of CNV, regardless of VA, facilitates early diagnosis in the fellow eye. Adherence to follow-up in the routine clinic setting also facilitates early detection of CNV.

Cullin-4 regulates Wingless and JNK signaling-mediated cell death in the Drosophila eye

PubMed Central

Tare, Meghana; Sarkar, Ankita; Bedi, Shimpi; Kango-Singh, Madhuri; Singh, Amit

2016-01-01

In all multicellular organisms, the fundamental processes of cell proliferation and cell death are crucial for growth regulation during organogenesis. Strict regulation of cell death is important to maintain tissue homeostasis by affecting processes like regulation of cell number, and elimination of unwanted/unfit cells. The developing Drosophila eye is a versatile model to study patterning and growth, where complex signaling pathways regulate growth and cell survival. However, the molecular mechanisms underlying regulation of these processes is not fully understood. In a gain-of-function screen, we found that misexpression of cullin-4 (cul-4), an ubiquitin ligase, can rescue reduced eye mutant phenotypes. Previously, cul-4 has been shown to regulate chromatin remodeling, cell cycle and cell division. Genetic characterization of cul-4 in the developing eye revealed that loss-of-function of cul-4 exhibits a reduced eye phenotype. Analysis of twin-spots showed that in comparison with their wild-type counterparts, the cul-4 loss-of-function clones fail to survive. Here we show that cul-4 clones are eliminated by induction of cell death due to activation of caspases. Aberrant activation of signaling pathways is known to trigger cell death in the developing eye. We found that Wingless (Wg) and c-Jun-amino-terminal-(NH2)-Kinase (JNK) signaling are ectopically induced in cul-4 mutant clones, and these signals co-localize with the dying cells. Modulating levels of Wg and JNK signaling by using agonists and antagonists of these pathways demonstrated that activation of Wg and JNK signaling enhances cul-4 mutant phenotype, whereas downregulation of Wg and JNK signaling rescues the cul-4 mutant phenotypes of reduced eye. Here we present evidences to demonstrate that cul-4 is involved in restricting Wg signaling and downregulation of JNK signaling-mediated cell death during early eye development. Overall, our studies provide insights into a novel role of cul-4 in promoting cell survival in the developing Drosophila eye. PMID:28032862

Non-mydriatic video ophthalmoscope to measure fast temporal changes of the human retina

NASA Astrophysics Data System (ADS)

Tornow, Ralf P.; Kolář, Radim; Odstrčilík, Jan

2015-07-01

The analysis of fast temporal changes of the human retina can be used to get insight to normal physiological behavior and to detect pathological deviations. This can be important for the early detection of glaucoma and other eye diseases. We developed a small, lightweight, USB powered video ophthalmoscope that allows taking video sequences of the human retina with at least 25 frames per second without dilating the pupil. Short sequences (about 10 s) of the optic nerve head (20° x 15°) are recorded from subjects and registered offline using two-stage process (phase correlation and Lucas-Kanade approach) to compensate for eye movements. From registered video sequences, different parameters can be calculated. Two applications are described here: measurement of (i) cardiac cycle induced pulsatile reflection changes and (ii) eye movements and fixation pattern. Cardiac cycle induced pulsatile reflection changes are caused by changing blood volume in the retina. Waveform and pulse parameters like amplitude and rise time can be measured in any selected areas within the retinal image. Fixation pattern ΔY(ΔX) can be assessed from eye movements during video acquisition. The eye movements ΔX[t], ΔY[t] are derived from image registration results with high temporal (40 ms) and spatial (1,86 arcmin) resolution. Parameters of pulsatile reflection changes and fixation pattern can be affected in beginning glaucoma and the method described here may support early detection of glaucoma and other eye disease.

Opposing interactions between homothorax and Lobe define the ventral eye margin of Drosophila eye

PubMed Central

Singh, Amit; Tare, Meghana; Kango-Singh, Madhuri; Son, Won-Seok; Cho, Kyung-Ok; Choi, Kwang-wook

2011-01-01

SUMMARY Patterning in multi-cellular organisms involves progressive restriction of cell fates by generation of boundaries to divide an organ primordium into smaller fields. We have employed the Drosophila eye model to understand the genetic circuitry responsible for defining the boundary between the eye and the head cuticle on the ventral margin. The default state of the early eye is ventral and depends on the function of Lobe (L) and the Notch ligand Serrate (Ser). We identified homothorax (hth) as a strong enhancer of the L mutant phenotype of loss of ventral eye. Hth is a MEIS class gene with a highly conserved Meis-Hth (MH) domain and a homeodomain (HD). Hth is known to bind Extradenticle (Exd) via its MH domain for its nuclear translocation. Loss-of-function of hth, a negative regulator of eye, results in ectopic ventral eye enlargements. This phenotype is complementary to the L mutant phenotype of loss-of-ventral eye. However, if L and hth interact during ventral eye development remains unknown. Here we show that (i) L acts antagonistically to hth, (ii) Hth is upregulated in the L mutant background, and (iii) MH domain of Hth is required for its genetic interaction with L, while its homeodomain is not, (iv) in L mutant background ventral eye suppression function of Hth involves novel MH domain-dependent factor(s), (v) Nuclear localization of Exd is not sufficient to mediate the Hth function in the L mutant background. Further, Exd is not a critical rate-limiting factor for the Hth function. Thus, optimum levels of L and Hth are required to define the boundary between the developing eye and head cuticle on the ventral margin. PMID:21920354

Novel methodology to examine cognitive and experiential factors in language development: combining eye-tracking and LENA technology

PubMed Central

Odean, Rosalie; Nazareth, Alina; Pruden, Shannon M.

2015-01-01

Developmental systems theory posits that development cannot be segmented by influences acting in isolation, but should be studied through a scientific lens that highlights the complex interactions between these forces over time (Overton, 2013a). This poses a unique challenge for developmental psychologists studying complex processes like language development. In this paper, we advocate for the combining of highly sophisticated data collection technologies in an effort to move toward a more systemic approach to studying language development. We investigate the efficiency and appropriateness of combining eye-tracking technology and the LENA (Language Environment Analysis) system, an automated language analysis tool, in an effort to explore the relation between language processing in early development, and external dynamic influences like parent and educator language input in the home and school environments. Eye-tracking allows us to study language processing via eye movement analysis; these eye movements have been linked to both conscious and unconscious cognitive processing, and thus provide one means of evaluating cognitive processes underlying language development that does not require the use of subjective parent reports or checklists. The LENA system, on the other hand, provides automated language output that describes a child’s language-rich environment. In combination, these technologies provide critical information not only about a child’s language processing abilities but also about the complexity of the child’s language environment. Thus, when used in conjunction these technologies allow researchers to explore the nature of interacting systems involved in language development. PMID:26379591

Early physical and motor development of mouse offspring exposed to valproic acid throughout intrauterine development.

PubMed

Podgorac, Jelena; Pešić, Vesna; Pavković, Željko; Martać, Ljiljana; Kanazir, Selma; Filipović, Ljupka; Sekulić, Slobodan

2016-09-15

Clinical research has identified developmental delay and physical malformations in children prenatally exposed to the antiepileptic drug (AED) valproic acid (VPA). However, the early signs of neurodevelopmental deficits, their evolution during postnatal development and growth, and the dose effects of VPA are not well understood. The present study aimed to examine the influence of maternal exposure to a wide dose range (50, 100, 200 and 400mg/kg/day) of VPA during breeding and gestation on early physical and neuromotor development in mice offspring. Body weight gain, eye opening, the surface righting reflex (SRR) and tail suspension test (TST) were examined in the offspring at postnatal days 5, 10 and 15. We observed that: (1) all tested doses of VPA reduced the body weight of the offspring and the timing of eye opening; (2) offspring exposed to VPA displayed immature forms of righting and required more time to complete the SRR; (3) latency for the first immobilization in the TST is shorter in offspring exposed to higher doses of VPA; however, mice in all groups exposed to VPA exhibited atypical changes in this parameter during the examined period of maturation; (4) irregularities in swinging and curling activities were observed in animals exposed to higher doses of VPA. This study points to delayed somatic development and postponed maturation of the motor system in all of the offspring prenatally exposed to VPA, with stronger effects observed at higher doses. The results implicate that the strategy of continuous monitoring of general health and achievements in motor milestones during the early postnatal development in prenatally VPA-exposed offspring, irrespectively of the dose applied, could help to recognize early developmental irregularities. Copyright © 2016 Elsevier B.V. All rights reserved.

Utilization of Telehealth Technology to Develop and Implement a Comprehensive Management Initiative for Chronic Diseases

DTIC Science & Technology

2011-10-01

Diabetic Retinopathy Study Research Group, 1981; Early Treatment Diabetic Retinopathy Research Group, 1991). Diabetes -related vision loss is often...2001; Chow et al., 2006). For diagnosis of diabetic retinopathy and diabetic macular edema, the telehealth eye care assessments agree substantially...with mydriatic seven-standard field Early Treatment Diabetic Retinopathy Study (ETDRS) protocol photography (Bursell et al., 2001) and with dilated

Eye contrast polarity is critical for face recognition by infants.

PubMed

Otsuka, Yumiko; Motoyoshi, Isamu; Hill, Harold C; Kobayashi, Megumi; Kanazawa, So; Yamaguchi, Masami K

2013-07-01

Just as faces share the same basic arrangement of features, with two eyes above a nose above a mouth, human eyes all share the same basic contrast polarity relations, with a sclera lighter than an iris and a pupil, and this is unique among primates. The current study examined whether this bright-dark relationship of sclera to iris plays a critical role in face recognition from early in development. Specifically, we tested face discrimination in 7- and 8-month-old infants while independently manipulating the contrast polarity of the eye region and of the rest of the face. This gave four face contrast polarity conditions: fully positive condition, fully negative condition, positive face with negated eyes ("negative eyes") condition, and negated face with positive eyes ("positive eyes") condition. In a familiarization and novelty preference procedure, we found that 7- and 8-month-olds could discriminate between faces only when the contrast polarity of the eyes was preserved (positive) and that this did not depend on the contrast polarity of the rest of the face. This demonstrates the critical role of eye contrast polarity for face recognition in 7- and 8-month-olds and is consistent with previous findings for adults. Copyright © 2013 Elsevier Inc. All rights reserved.

Modulation of the Early Inflammatory Microenvironment in the Alkali-Burned Eye by Systemically Administered Interferon-γ-Treated Mesenchymal Stromal Cells

PubMed Central

Javorkova, Eliska; Trosan, Peter; Zajicova, Alena; Krulova, Magdalena; Hajkova, Michaela

2014-01-01

The aim of this study was to investigate the effects of systemically administered bone-marrow-derived mesenchymal stromal cells (MSCs) on the early acute phase of inflammation in the alkali-burned eye. Mice with damaged eyes were either untreated or treated 24 h after the injury with an intravenous administration of fluorescent-dye-labeled MSCs that were unstimulated or pretreated with interleukin-1α (IL-1α), transforming growth factor-β (TGF-β), or interferon-γ (IFN-γ). Analysis of cell suspensions prepared from the eyes of treated mice on day 3 after the alkali burn revealed that MSCs specifically migrated to the damaged eye and that the number of labeled MSCs was more than 30-times higher in damaged eyes compared with control eyes. The study of the composition of the leukocyte populations within the damaged eyes showed that all types of tested MSCs slightly decreased the number of infiltrating lymphoid and myeloid cells, but only MSCs pretreated with IFN-γ significantly decreased the percentage of eye-infiltrating cells with a more profound effect on myeloid cells. Determining cytokine and NO production in the damaged eyes confirmed that the most effective immunomodulation was achieved with MSCs pretreated with IFN-γ, which significantly decreased the levels of the proinflammatory molecules IL-1α, IL-6, and NO. Taken together, the results show that systemically administered MSCs specifically migrate to the damaged eye and that IFN-γ-pretreated MSCs are superior in inhibiting the acute phase of inflammation, decreasing leukocyte infiltration, and attenuating the early inflammatory environment. PMID:24849741

Interactive stereo games to improve vision in children with amblyopia using dichoptic stimulation

NASA Astrophysics Data System (ADS)

Herbison, Nicola; Ash, Isabel M.; MacKeith, Daisy; Vivian, Anthony; Purdy, Jonathan H.; Fakis, Apostolos; Cobb, Sue V.; Hepburn, Trish; Eastgate, Richard M.; Gregson, Richard M.; Foss, Alexander J. E.

2015-03-01

Amblyopia is a common condition affecting 2% of all children and traditional treatment consists of either wearing a patch or penalisation. We have developed a treatment using stereo technology, not to provide a 3D image but to allow dichoptic stimulation. This involves presenting an image with the same background to both eyes but with features of interest removed from the image presented to the normal eye with the aim to preferentially stimulated visual development in the amblyopic, or lazy, eye. Our system, called I-BiT can use either a game or a video (DVD) source as input. Pilot studies show that this treatment is effective with short treatment times and has proceeded to randomised controlled clinical trial. The early indications are that the treatment has a high degree of acceptability and corresponding good compliance.

The Role of Early Visual Attention in Social Development

ERIC Educational Resources Information Center

Wagner, Jennifer B.; Luyster, Rhiannon J.; Yim, Jung Yeon; Tager-Flusberg, Helen; Nelson, Charles A.

2013-01-01

Faces convey important information about the social environment, and even very young infants are preferentially attentive to face-like over non-face stimuli. Eye-tracking studies have allowed researchers to examine which features of faces infants find most salient across development, and the present study examined scanning of familiar (i.e.,…

Turning into Teachers before Our Eyes: The Development of Professional Identity through Professional Dialogue

ERIC Educational Resources Information Center

Mantei, Jessica; Kervin, Lisa

2011-01-01

This paper examines the development of professional identity in early career teachers enrolled in an "add-on year" of an undergraduate teacher education degree. Through a series of readings focused on reflection and pedagogy, participants engaged in professional dialogue as they made connections between the themes in their professional…

Alterations in molecular pathways in the retina of early experimental glaucoma eyes

PubMed Central

Cao, Li; Wang, Lin; Cull, Grant; Zhou, An

2015-01-01

Glaucoma is a multifactorial, neurodegenerative disease. The molecular mechanisms that underlie the pathophysiological changes in glaucomatous eyes, especially at the early stage of the disease, are poorly understood. Here, we report the findings from a quantitative proteomic analysis of retinas from experimental glaucoma (EG) eyes. An early stage of EG was modeled on unilateral eyes of five nonhuman primates (NHP) by laser treatment-induced elevation of intraocular pressure (IOP). Retinal proteins were extracted from individual EG eyes and their contralateral control eyes of the same animals, respectively, and analyzed by quantitative mass spectrometry (MS). As a result, a total, 475 retinal proteins were confidently identified and quantified. Results of bioinformatic analysis of proteins that showed an increase in the EG eyes suggested changes in apoptosis, DNA damage, immune response, cytoskeleton rearrangement and cell adhesion processes. Interestingly, hemoglobin subunit alpha (HBA) and Ras related C3 botulinum toxin substrate 1 (Rac1) were among the increased proteins. Results of molecular modeling of HBA- and Rac1-associated signaling network implicated the involvement of Mitogen-Activated Protein Kinase (MAPK) pathway in the EG, through which Rac1 may exert a regulatory role on HBA. This is the first observation of this potentially novel signaling network in the NHP retina and in EG. Results of Western blot analyses for Rac1, HBA and a selected MAPK pathway protein indicated synergistic changes in all three proteins in the EG eyes. Further, results of hierarchical cluster analysis of proteomes of control eyes revealed a clear age-proteome relationship, and such relationship appeared disrupted in the EG eyes. In conclusion, our results suggested an increased presence of a potentially novel signaling network at the early stage of glaucoma, and age might be one of the determinant factors in retinal proteomic characteristics under normal conditions. PMID:26069528

A Compact Fiber Optic Eye Diagnostic System

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.; Suh, Kwang I.; Dubin, Stephen; Dellavecchia, Michael A.

1995-01-01

A new fiber optic probe developed for determining transport properties of sub-micron particles in fluid experiments in a microgravity environment has been applied to study different parts of an eye. The probe positioned in front of an eye, delivers a low power (approximately few microW) light from a laser diode into the eye and guides the light which is back scattered by different components (aqueous humor, lens, and vitreous humor) of the eye through a receiving optical fiber to a photo detector. The probe provides rapid determination of macromolecular diffusivities and their respective size distributions in the eye lens and the gel-like materials in the vitreous humor. In a clinical setting, the probe can be mounted on a standard slit-lamp apparatus simply using a Hruby lens holder. The capability of detecting cataracts, both nuclear and cortical, in their early stages of formation, in a non invasive and quantitative fashion, has the potential in patient monitoring and in developing and testing new drugs or diet therapies to 'dissolve' or slow down the cataract formation before the surgery becomes necessary. The ability to detect biochemical and macromolecular changes in the vitreous structure can be very useful in identifying certain diseases of the posterior chamber and their complications, e.g., posterior vitreous detachment and diabetic retinopathy.

A Compact Fiber Optic Eye Diagnostics System

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.; Suh, Kwang I.; DellaVecchia, Michael A.; Dubin, Stephen; Zigler, J. Samuel, Jr.

1995-01-01

A new fiber optic probe development for determining transport properties of sub-micron particles in fluids experiments in a microgravity environment has been applied to study different parts of the eye. The probe positioned in front of an eye, delivers a low power (approximately a few mu W) light from a laser diode into the eye and guides the light which is back scattered by different components (aqueous humor, lens, and vitreous humor) of the eye through a receiving optical fiber to a photo detector. The probe provides rapid determination of macromolecular diffusivities and their respective size distributions in the eye lens and the gel-like material in the vitreous humor. For a clinical use, the probe is mounted on a standard slit-lamp apparatus simply using Hruby lens holder. The capability of detecting cataracts, both nuclear and cortical, in their early stages of formation, in a non invasive and quantitative fashion, has the potential in patient monitoring and in developing and testing new drugs or diet therapies to 'dissolve' or slow down the cataract formation before the surgery becomes necessary. The ability to detect biochemical and macromolecular changes in the vitreous structure can be very useful in identifying certain diseases of the posterior chamber and their complications, e.g., posterior vitreous detachment and diabetic retinopathy.

Eye tracking reveals a crucial role for facial motion in recognition of faces by infants

PubMed Central

Xiao, Naiqi G.; Quinn, Paul C.; Liu, Shaoying; Ge, Liezhong; Pascalis, Olivier; Lee, Kang

2015-01-01

Current knowledge about face processing in infancy comes largely from studies using static face stimuli, but faces that infants see in the real world are mostly moving ones. To bridge this gap, 3-, 6-, and 9-month-old Asian infants (N = 118) were familiarized with either moving or static Asian female faces and then their face recognition was tested with static face images. Eye tracking methodology was used to record eye movements during familiarization and test phases. The results showed a developmental change in eye movement patterns, but only for the moving faces. In addition, the more infants shifted their fixations across facial regions, the better was their face recognition, but only for the moving faces. The results suggest that facial movement influences the way faces are encoded from early in development. PMID:26010387

Mfsd2a Is a Transporter for the Essential ω-3 Fatty Acid Docosahexaenoic Acid (DHA) in Eye and Is Important for Photoreceptor Cell Development.

PubMed

Wong, Bernice H; Chan, Jia Pei; Cazenave-Gassiot, Amaury; Poh, Rebecca W; Foo, Juat Chin; Galam, Dwight L A; Ghosh, Sujoy; Nguyen, Long N; Barathi, Veluchamy A; Yeo, Sia W; Luu, Chi D; Wenk, Markus R; Silver, David L

2016-05-13

Eye photoreceptor membrane discs in outer rod segments are highly enriched in the visual pigment rhodopsin and the ω-3 fatty acid docosahexaenoic acid (DHA). The eye acquires DHA from blood, but transporters for DHA uptake across the blood-retinal barrier or retinal pigment epithelium have not been identified. Mfsd2a is a newly described sodium-dependent lysophosphatidylcholine (LPC) symporter expressed at the blood-brain barrier that transports LPCs containing DHA and other long-chain fatty acids. LPC transport via Mfsd2a has been shown to be necessary for human brain growth. Here we demonstrate that Mfsd2a is highly expressed in retinal pigment epithelium in embryonic eye, before the development of photoreceptors, and is the primary site of Mfsd2a expression in the eye. Eyes from whole body Mfsd2a-deficient (KO) mice, but not endothelium-specific Mfsd2a-deficient mice, were DHA-deficient and had significantly reduced LPC/DHA transport in vivo Fluorescein angiography indicated normal blood-retinal barrier function. Histological and electron microscopic analysis indicated that Mfsd2a KO mice exhibited a specific reduction in outer rod segment length, disorganized outer rod segment discs, and mislocalization of and reduction in rhodopsin early in postnatal development without loss of photoreceptors. Minor photoreceptor cell loss occurred in adult Mfsd2a KO mice, but electroretinography indicated visual function was normal. The developing eyes of Mfsd2a KO mice had activated microglia and up-regulation of lipogenic and cholesterogenic genes, likely adaptations to loss of LPC transport. These findings identify LPC transport via Mfsd2a as an important pathway for DHA uptake in eye and for development of photoreceptor membrane discs. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Electronic eye occluder with time-counting and reflection control

NASA Astrophysics Data System (ADS)

Karitans, V.; Ozolinsh, M.; Kuprisha, G.

2008-09-01

In pediatric ophthalmology 2 - 3 % of all the children are impacted by a visual pathology - amblyopia. It develops if a clear image isn't presented to the retina during an early stage of the development of the visual system. A common way of treating this pathology is to cover the better-seeing eye to force the "lazy" eye to learn seeing. However, children are often reluctant to wear such an occluder because they are ashamed or simply because they find it inconvenient. This fact requires to find a way how to track the regime of occlusion because results of occlusion is a hint that the actual regime of occlusion isn't that what the optometrist has recommended. We design an electronic eye occluder that allows to track the regime of eye occlusion. We employ real-time clock DS1302 providing time information from seconds to years. Data is stored in the internal memory of the CPU (EEPROM). The MCU (PIC16F676) switches on only if a mechanical switch is closed and temperature has reached a satisfactory level. The occlusion is registered between time moments when the infrared signal appeared and disappeared.

Abnormal Eye Movements in Creutzfeldt-Jakob Disease

NASA Technical Reports Server (NTRS)

Grant, Michael P.; Cohen, Mark; Petersen, Robert B.; Halmagyi, G. Michael; McDougall, Alan; Tusa, Ronald J.; Leigh, R. John

1993-01-01

We report 3 patients with autopsy-proven Creutzfeldt-Jakob disease who, early in their course, developed abnormal eye movements that included periodic alternating nystagmus and slow vertical saccades. These findings suggested involvement of the cerebellar nodulus and uvula, and the brainstem reticular formation, respectively. Cerebellar ataxia was also an early manifestation and, in one patient, a frontal lobe brain biopsy was normal at a time when ocular motor and cerebellar signs were conspicuous. As the disease progressed, all saccades and quick phases of nystagmus were lost, but periodic alternating gaze deviation persisted. At autopsy, 2 of the 3 patients had pronounced involvement of the cerebellum, especially of the midline structures. Creutzfeldt-Jakob disease should be considered in patients with subacute progressive neurological disease when cognitive changes are overshadowed by ocular motor findings or ataxia.

Rapidly progressive idiopathic lenticular astigmatism.

PubMed

Tint, Naing L; Jayaswal, Rakesh; Masood, Imran; Maharajan, V Senthil

2007-02-01

A myopic 43-year-old woman with early nuclear sclerotic cataract developed more than 11.0 diopters (D) of astigmatism over a 6-month period. This was found to be lenticular in origin. Phacoemulsification with intraocular lens implantation was performed, resulting in residual astigmatism of 0.75 D. To our knowledge, this is the first case of rapidly progressive lenticular astigmatism in an otherwise healthy eye with early nuclear sclerotic cataract.

Optical Design and Optimization of Translational Reflective Adaptive Optics Ophthalmoscopes

NASA Astrophysics Data System (ADS)

Sulai, Yusufu N. B.

The retina serves as the primary detector for the biological camera that is the eye. It is composed of numerous classes of neurons and support cells that work together to capture and process an image formed by the eye's optics, which is then transmitted to the brain. Loss of sight due to retinal or neuro-ophthalmic disease can prove devastating to one's quality of life, and the ability to examine the retina in vivo is invaluable in the early detection and monitoring of such diseases. Adaptive optics (AO) ophthalmoscopy is a promising diagnostic tool in early stages of development, still facing significant challenges before it can become a clinical tool. The work in this thesis is a collection of projects with the overarching goal of broadening the scope and applicability of this technology. We begin by providing an optical design approach for AO ophthalmoscopes that reduces the aberrations that degrade the performance of the AO correction. Next, we demonstrate how to further improve image resolution through the use of amplitude pupil apodization and non-common path aberration correction. This is followed by the development of a viewfinder which provides a larger field of view for retinal navigation. Finally, we conclude with the development of an innovative non-confocal light detection scheme which improves the non-invasive visualization of retinal vasculature and reveals the cone photoreceptor inner segments in healthy and diseased eyes.

Mild decentration measured by a Scheimpflug camera and its impact on visual quality following SMILE in the early learning curve.

PubMed

Li, Meiyan; Zhao, Jing; Miao, Huamao; Shen, Yang; Sun, Ling; Tian, Mi; Wadium, Elizabeth; Zhou, Xingtao

2014-05-20

To measure decentration following femtosecond laser small incision lenticule extraction (SMILE) for the correction of myopia and myopic astigmatism in the early learning curve, and to investigate its impact on visual quality. A total of 55 consecutive patients (100 eyes) who underwent the SMILE procedure were included. Decentration was measured using a Scheimpflug camera 6 months after surgery. Uncorrected and corrected distance visual acuity (UDVA, CDVA), manifest refraction, and wavefront errors were also measured. Associations between decentration and the preoperative spherical equivalent were analyzed, as well as the associations between decentration and wavefront aberrations. Regarding efficacy and safety, 40 eyes (40%) had an unchanged CDVA; 32 eyes (32%) gained one line; and 11 eyes (11%) gained two lines. Fifteen eyes (15%) lost one line of CDVA, and two eyes (2%) lost two lines. Ninety-nine of the treated eyes (99%) had a postoperative UDVA better than 1.0, and 100 eyes (100%) had a UDVA better than 0.8. The mean decentered displacement was 0.17 ± 0.09 mm. The decentered displacement of all treated eyes (100%) was within 0.50 mm; 70 eyes (70%) were within 0.20 mm; and 90 eyes (90%) were within 0.30 mm. The vertical coma showed the greatest increase in magnitude. The magnitude of horizontal decentration was found to be associated with an induced horizontal coma. This study suggests that, although mild decentration occurred in the early learning curve, good visual outcomes were achieved after the SMILE surgery. Special efforts to minimize induced vertical coma are necessary. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Characteristics of choroidal neovascularization in the complications of age-related macular degeneration prevention trial.

PubMed

Maguire, Maureen G; Alexander, Judith; Fine, Stuart L

2008-09-01

To describe the characteristics of incident choroidal neovascularization (CNV) in observed and treated eyes in the Complications of Age-related Macular Degeneration Prevention Trial (CAPT). Cross-sectional descriptive study within a multicenter, randomized clinical trial. Patients who developed CNV during CAPT follow-up. Inclusion criteria for CAPT specified bilateral large drusen (>or=10 drusen at least 125 micro), visual acuity >or=20/40 in each eye, and age >or=50. Exclusion criteria included CNV and geographic atrophy >1 Macular Photocoagulation Study (MPS) disc area or within 500 micro of the foveal center. One eye of each person was selected randomly for low-intensity laser treatment and the contralateral eye was observed. Fluorescein angiography was performed at baseline, annually for >or=5 years, and whenever there were symptoms of CNV. Trained readers at the CAPT Photograph Reading Center assessed color stereo photographs and angiogram negatives to identify CNV. Choroidal neovascularization was classified by type (predominantly classic CNV, minimally classic CNV, occult only CNV, or scar), location, and area. Visual acuity was measured by certified examiners. Symmetry of characteristics between eyes of bilaterally affected patients was examined. Choroidal neovascularization developed in 282 eyes of 225 patients. At the time of detection, 192 (68%) of the lesions were occult only, 153 (54%) were subfoveal, and 157 (56%) were or=20/40 in 123 (69%) of 179 eyes with visual acuity measured at the time of detection. Choroidal neovascularization developed in both eyes in 57 patients (25%) during CAPT follow-up. Lesions in eyes of bilaterally affected patients were no more similar to each other than affected eyes in 2 different patients. When patients are monitored closely, many CNV lesions can be detected outside of the fovea and when they are relatively small. Early detection may lead to improved long-term visual acuity.

Discriminating anisometropic amblyopia from myopia based on interocular inhibition

PubMed Central

Jia, Wuli; Zhou, Jiawei; Lu, Zhong-Lin; Lesmes, Luis A.; Huang, Chang-Bing

2016-01-01

Amblyopia screening during childhood is critical for early detection and successful treatment. In the current study, we develop and evaluate a screening method that exploits the imbalanced interocular inhibition between amblyopic and fellow eyes. In nineteen subjects with anisometropic amblyopia and twenty-two age-matched subjects with myopia, we measured the area under the contrast sensitivity functions (AUCSFs) in eight monocular conditions defined by tested eye (left, right), patching of the untested eye (translucent, opaque), and refractive status (corrected, uncorrected). For each test eye, we defined the inhibition index as the ratio between AUCSF values obtained in the translucent and opaque patching conditions of the untested eye. To evaluate the screening potential of the inhibition index, we compared results from patients with amblyopia and myopia. With and without optical correction, the index was significantly lower in the amblyopic eye than in the fellow eye of the amblyopic subjects and both eyes of the myopic subjects. No significant difference was found among the two eyes of the myopic subjects and the fellow eyes of the amblyopic subjects. With the inhibition index as the predictor, a logistic regression model successfully discriminated amblyopic eyes from myopic eyes with 100% accuracy in the uncorrected condition. In the corrected condition, with the inhibition index and interocular visual acuity difference as predictors, amblyopic eyes were likewise discriminated from myopic eyes with 100% accuracy. This pattern of CSF changes, caused by the different patching modes of the untested eye, provides a potential CSF signature to discriminate anisometropic amblyopia from myopia. PMID:25701741

Retinal Wave Patterns Are Governed by Mutual Excitation among Starburst Amacrine Cells and Drive the Refinement and Maintenance of Visual Circuits

PubMed Central

Xu, Hong-Ping; Burbridge, Timothy J.; Ye, Meijun; Chen, Minggang; Ge, Xinxin; Zhou, Z. Jimmy

2016-01-01

Retinal waves are correlated bursts of spontaneous activity whose spatiotemporal patterns are critical for early activity-dependent circuit elaboration and refinement in the mammalian visual system. Three separate developmental wave epochs or stages have been described, but the mechanism(s) of pattern generation of each and their distinct roles in visual circuit development remain incompletely understood. We used neuroanatomical, in vitro and in vivo electrophysiological, and optical imaging techniques in genetically manipulated mice to examine the mechanisms of wave initiation and propagation and the role of wave patterns in visual circuit development. Through deletion of β2 subunits of nicotinic acetylcholine receptors (β2-nAChRs) selectively from starburst amacrine cells (SACs), we show that mutual excitation among SACs is critical for Stage II (cholinergic) retinal wave propagation, supporting models of wave initiation and pattern generation from within a single retinal cell type. We also demonstrate that β2-nAChRs in SACs, and normal wave patterns, are necessary for eye-specific segregation. Finally, we show that Stage III (glutamatergic) retinal waves are not themselves necessary for normal eye-specific segregation, but elimination of both Stage II and Stage III retinal waves dramatically disrupts eye-specific segregation. This suggests that persistent Stage II retinal waves can adequately compensate for Stage III retinal wave loss during the development and refinement of eye-specific segregation. These experiments confirm key features of the “recurrent network” model for retinal wave propagation and clarify the roles of Stage II and Stage III retinal wave patterns in visual circuit development. SIGNIFICANCE STATEMENT Spontaneous activity drives early mammalian circuit development, but the initiation and patterning of activity vary across development and among modalities. Cholinergic “retinal waves” are initiated in starburst amacrine cells and propagate to retinal ganglion cells and higher-order visual areas, but the mechanism responsible for creating their unique and critical activity pattern is incompletely understood. We demonstrate that cholinergic wave patterns are dictated by recurrent connectivity within starburst amacrine cells, and retinal ganglion cells act as “readouts” of patterned activity. We also show that eye-specific segregation occurs normally without glutamatergic waves, but elimination of both cholinergic and glutamatergic waves completely disrupts visual circuit development. These results suggest that each retinal wave pattern during development is optimized for concurrently refining multiple visual circuits. PMID:27030771

Relationship of Basal laminar deposit and membranous debris to the clinical presentation of early age-related macular degeneration.

PubMed

Sarks, Shirley; Cherepanoff, Svetlana; Killingsworth, Murray; Sarks, John

2007-03-01

To correlate basal laminar deposit (BLamD) and membranous debris, including basal linear deposit (BLinD), with the evolution of early age-related macular degeneration (AMD). A clinicopathologic collection of 132 eyes with a continuous layer of BLamD was reviewed. The thickness and type of BLamD and the sites of membranous debris deposition were correlated with the clinical progression of the disease. Two types of BLamD, termed early and late, were identified based on light microscopic appearance by using the picro-Mallory stain. The progressive accumulation of late type BLamD correlated well with increasing BLamD thickness, advancing RPE degeneration, poorer vision, increasing age, and clinically evident pigment changes. Membranous debris initially accumulated diffusely as BLinD, most eyes with BLinD and early BLamD remaining funduscopically normal. However, membranous debris also formed focal collections as basal mounds internal to the RPE basement membrane and as soft drusen external to the basement membrane. Eyes in which membranous debris remained confined to basal mounds belonged to older patients with poorer vision, whereas patients with soft drusen were younger and had better vision. The presence of BLinD and early BLamD define threshold AMD, which manifests clinically as a normal fundus. Although late BLamD correlates most closely with clinical pigment abnormalities, it is the quantity and sites of membranous debris accumulation that appear to determine whether the disease develops pigment changes only or follows the alternative pathway of soft drusen formation with its attendant greater risk of choroidal neovascularization (CNV).

How can clinicians detect and treat autism early? Methodological trends of technology use in research

PubMed Central

Bölte, S; Bartl-Pokorny, KD; Jonsson, U; Berggren, S; Zhang, D; Kostrzewa, E; Falck-Ytter, T; Einspieler, C; Pokorny, FB; Jones, EJH; Roeyers, H; Charman, T; Marschik, PB

2018-01-01

We reviewed original research papers that used quantifiable technology to detect early autism spectrum disorder (ASD) and identified 376 studies from 34 countries from 1965-2013. Publications have increased significantly since 2000, with most coming from the USA. Electroencephalogram, magnetic resonance imaging and eye-tracking were the most frequently used technologies. Conclusion The use of quantifiable technology to detect early ASD has increased in recent decades, but has had limited impact on early detection and treatment. Further scientific developments are anticipated and we hope that they will increasingly be used in clinical practice for early ASD screening, diagnosis and intervention. PMID:26479859

[Clinical evaluation of the effectiveness of cholinesterase inhibition with neuromidin in the treatment of primary glaucoma patients].

PubMed

Zakharova, I A; Avdeev, R V; Pristavka, V A; Surnin, S N; Makhmutov, V Yu; Savrasova, I I

to investigate neuromidin effectiveness in the treatment of patients with primary glaucoma and compensated intraocular pressure (IOP). A total of 40 patients (80 eyes) were examined. Of them, 10 eyes with early glaucoma, 36 eyes with moderate-stage glaucoma, 33 eyes with advanced glaucoma, and 1 eye with end-stage glaucoma. In 19 eyes, IOP was controlled through beta-blockers, in 11 eyes - through carbonic anhydrase inhibitors, in 10 eyes - through prostaglandin analogues, and in 39 eyes - through combination drugs. Twenty-six eyes had received glaucoma surgery some time earlier. Ipidacrine was prescribed in tablets at 20 mg 2 times daily for 25 days. Treatment effectiveness was judged by visual functions, hydrodynamics, and morphometric parameters of the optic disc. In moderate-stage eyes, visual acuity improved in 66.6% of cases and remained unchanged in 33.3%. In advanced-stage eyes, visual acuity improved in 51.5% of cases and remained unchanged in 48.5%. Visual field broadened in all cases. Moreover, under the neuromidin therapy, the number of scotomas in early-stage eyes decreased, while the number of areas with normal sensitivity of the retina increased by 14.9%. In advanced-stage glaucoma, the effect was less pronounced: the number of type 1 and type 2 scotomas decreased by 3.0±0.6% and 2.9±0.8%, respectively; the number of absolute scotomas did not change; the number of areas with normal sensitivity of the retina increased by 7.4±2.0%. Also, P0 was found to be reduced and intraocular fluid outflow - activated. In early and moderate glaucoma, there was a significant reduction in the cup area as well as an increase in the neuroretinal rim area and retinal nerve fiber layer thickness. In advanced-stage cases, it was only the retinal nerve fiber layer thickness that changed. Neuromidin has a positive impact on visual function, hydrodynamics, and morphometric parameters of the optic disc.

Psychological implications of a vision disorder.

PubMed

Weber, Brian E

2017-04-01

The paper discusses how the condition of crossed-eyes affects a baby's eye contact with mother and potentially results in the loss of a vital emotional connection with her during the earliest days of life. This loss may contribute to a rupture that arrests emotional development at a deep psychic level. It is suggested that, in the same way as premature separation, the rupture can precipitate a 'fusional complex', a defence that develops to protect the infant against psychotic anxieties. The paper proposes that psychological development atrophies in this place and creates a blind spot. These ideas are explored through analytic theory and developmental literature. The dreams of a patient and his art are used to illustrate a 10-year 'alchemical' process of bringing repressed material into consciousness and transformation. Healing the psychological wounds of deficits in early eye contact may be found to bring sight to a blind spot that was created by the nature of the condition itself. © 2017, The Society of Analytical Psychology.

Zebrafish mab21l2 is specifically expressed in the presumptive eye and tectum from early somitogenesis onwards.

PubMed

Kudoh, T; Dawid, I B

2001-11-01

Random screening for tissue specific genes in zebrafish by in situ hybridization led us to isolate a gene which showed highly restricted expression in the developing eyes and midbrain at somitogenesis stages. This gene was very similar to mouse and human mab21l2. The characteristic expression pattern of mab21l2 facilitates a detailed description of the morphogenesis of the eyes and midbrain in the zebrafish. In the eye field, mab21l2 expression illustrates the transformation of the eye field to form two separate eyes in the anterior neural plate. Mab21l2 staining in the cyclopic mutants, cyc and oep, exhibited incomplete splitting of the eye primodium. In the midbrain, mab21l2 is expressed in the tectum, and its expression follows the expansion of the tectal region. In mutants affecting the mid-hindbrain boundary (MHB), mab21l2 expression is affected differentially. In the noi/pax2.1 mutant, mab21l2 is down-regulated and the size of the tectum remains small, whereas in the ace/fgf8 mutant, mab21l2 expression persists although the shape of the tectum is altered.

DETECTION OF MICROVASCULAR CHANGES IN EYES OF PATIENTS WITH DIABETES BUT NOT CLINICAL DIABETIC RETINOPATHY USING OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

PubMed

de Carlo, Talisa E; Chin, Adam T; Bonini Filho, Marco A; Adhi, Mehreen; Branchini, Lauren; Salz, David A; Baumal, Caroline R; Crawford, Courtney; Reichel, Elias; Witkin, Andre J; Duker, Jay S; Waheed, Nadia K

2015-11-01

To evaluate the ability of optical coherence tomography angiography to detect early microvascular changes in eyes of diabetic individuals without clinical retinopathy. Prospective observational study of 61 eyes of 39 patients with diabetes mellitus and 28 control eyes of 22 age-matched healthy subjects that received imaging using optical coherence tomography angiography between August 2014 and March 2015. Eyes with concomitant retinal, optic nerve, and vitreoretinal interface diseases and/or poor-quality images were excluded. Foveal avascular zone size and irregularity, vessel beading and tortuosity, capillary nonperfusion, and microaneurysm were evaluated. Foveal avascular zone size measured 0.348 mm² (0.1085-0.671) in diabetic eyes and 0.288 mm² (0.07-0.434) in control eyes (P = 0.04). Foveal avascular zone remodeling was seen more often in diabetic than control eyes (36% and 11%, respectively; P = 0.01). Capillary nonperfusion was noted in 21% of diabetic eyes and 4% of control eyes (P = 0.03). Microaneurysms and venous beading were noted in less than 10% of both diabetic and control eyes. Both diabetic and healthy control eyes demonstrated tortuous vessels in 21% and 25% of eyes, respectively. Optical coherence tomography angiography was able to image foveal microvascular changes that were not detected by clinical examination in diabetic eyes. Changes to the foveal avascular zone and capillary nonperfusion were more prevalent in diabetic eyes, whereas vessel tortuosity was observed with a similar frequency in normal and diabetic eyes. Optical coherence tomography angiography may be able to detect diabetic eyes at risk of developing retinopathy and to screen for diabetes quickly and noninvasively before the systemic diagnosis is made.

20 CFR 10.313 - Will OWCP pay for preventive treatment?

Code of Federal Regulations, 2011 CFR

2011-04-01

... may be authorized. (d) Where injury to one eye has resulted in loss of vision, periodic examination of the uninjured eye to detect possible sympathetic involvement of the uninjured eye at an early stage. ...

20 CFR 10.313 - Will OWCP pay for preventive treatment?

Code of Federal Regulations, 2010 CFR

2010-04-01

... may be authorized. (d) Where injury to one eye has resulted in loss of vision, periodic examination of the uninjured eye to detect possible sympathetic involvement of the uninjured eye at an early stage. ...

Eye Development in Sepia officinalis Embryo: What the Uncommon Gene Expression Profiles Tell Us about Eye Evolution.

PubMed

Imarazene, Boudjema; Andouche, Aude; Bassaglia, Yann; Lopez, Pascal-Jean; Bonnaud-Ponticelli, Laure

2017-01-01

In metazoans, there is a remarkable diversity of photosensitive structures; their shapes, physiology, optical properties, and development are different. To approach the evolution of photosensitive structures and visual function, cephalopods are particularly interesting organisms due to their most highly centralized nervous system and their camerular eyes which constitute a convergence with those of vertebrates. The eye morphogenesis in numerous metazoans is controlled mainly by a conserved Retinal Determination Gene Network (RDGN) including pax, six, eya , and dac playing also key developmental roles in non-retinal structures and tissues of vertebrates and Drosophila . Here we have identified and explored the role of Sof-dac, Sof-six1/2, Sof-eya in eye morphogenesis, and nervous structures controlling the visual function in Sepia officinalis . We compare that with the already shown expressions in eye development of Sof-otx and Sof-pax genes. Rhodopsin is the pigment responsible for light sensitivity in metazoan, which correlate to correlate visual function and eye development. We studied Sof-rhodopsin expression during retina differentiation. By in situ hybridization, we show that (1) all of the RDGN genes, including Sof-pax6 , are expressed in the eye area during the early developmental stages but they are not expressed in the retina, unlike Sof-otx , which could have a role in retina differentiation; (2) Sof-rhodopsin is expressed in the retina just before vision gets functional, from stage 23 to hatching. Our results evidence a role of Sof-six1/2, Sof-eya , and Sof-dac in eye development. However, the gene network involved in the retinal photoreceptor differentiation remains to be determined. Moreover, for the first time, Sof-rhodopsin expression is shown in the embryonic retina of cuttlefish suggesting the evolutionary conservation of the role of rhodopsin in visual phototransduction within metazoans. These findings are correlated with the physiological and behavioral observations suggesting that S. officinalis is able to react to light stimuli from stage 25 of organogenesis on, as soon as the first retinal pigments appear.

Electroencephalographic prodromal markers of dementia across conscious states in Parkinson’s disease

PubMed Central

Latreille, Véronique; Gaudet-Fex, Benjamin; Rodrigues-Brazète, Jessica; Panisset, Michel; Chouinard, Sylvain; Postuma, Ronald B.

2016-01-01

Abstract In Parkinson’s disease, electroencephalographic abnormalities during wakefulness and non-rapid eye movement sleep (spindles) were found to be predictive biomarkers of dementia. Because rapid eye movement sleep is regulated by the cholinergic system, which shows early degeneration in Parkinson’s disease with cognitive impairment, anomalies during this sleep stage might mirror dementia development. In this prospective study, we examined baseline electroencephalographic absolute spectral power across three states of consciousness (non-rapid eye movement sleep, rapid eye movement sleep, and wakefulness) in 68 non-demented patients with Parkinson’s disease and 44 healthy controls. All participants underwent baseline polysomnographic recordings and a comprehensive neuropsychological assessment. Power spectral analyses were performed on standard frequency bands. Dominant occipital frequency during wakefulness and ratios of slow-to-fast frequencies during rapid eye movement sleep and wakefulness were also computed. At follow-up (an average 4.5 years after baseline), 18 patients with Parkinson’s disease had developed dementia and 50 patients remained dementia-free. In rapid eye movement sleep, patients with Parkinson’s disease who later developed dementia showed, at baseline, higher absolute power in delta and theta bands and a higher slowing ratio, especially in temporal, parietal, and occipital regions, compared to patients who remained dementia-free and controls. In non-rapid eye movement sleep, lower baseline sigma power in parietal cortical regions also predicted development of dementia. During wakefulness, patients with Parkinson’s disease who later developed dementia showed lower dominant occipital frequency as well as higher delta and slowing ratio compared to patients who remained dementia-free and controls. At baseline, higher slowing ratios in temporo-occipital regions during rapid eye movement sleep were associated with poor performance on visuospatial tests in patients with Parkinson’s disease. Using receiver operating characteristic curves, we found that best predictors of dementia in Parkinson’s disease were rapid eye movement sleep slowing ratios in posterior regions, wakefulness slowing ratios in temporal areas, and lower dominant occipital frequency. These results suggest that electroencephalographic slowing during sleep is a new promising predictive biomarker for Parkinson’s disease dementia, perhaps as a marker of cholinergic denervation. PMID:26912643

Eye Development in Sepia officinalis Embryo: What the Uncommon Gene Expression Profiles Tell Us about Eye Evolution

PubMed Central

Imarazene, Boudjema; Andouche, Aude; Bassaglia, Yann; Lopez, Pascal-Jean; Bonnaud-Ponticelli, Laure

2017-01-01

In metazoans, there is a remarkable diversity of photosensitive structures; their shapes, physiology, optical properties, and development are different. To approach the evolution of photosensitive structures and visual function, cephalopods are particularly interesting organisms due to their most highly centralized nervous system and their camerular eyes which constitute a convergence with those of vertebrates. The eye morphogenesis in numerous metazoans is controlled mainly by a conserved Retinal Determination Gene Network (RDGN) including pax, six, eya, and dac playing also key developmental roles in non-retinal structures and tissues of vertebrates and Drosophila. Here we have identified and explored the role of Sof-dac, Sof-six1/2, Sof-eya in eye morphogenesis, and nervous structures controlling the visual function in Sepia officinalis. We compare that with the already shown expressions in eye development of Sof-otx and Sof-pax genes. Rhodopsin is the pigment responsible for light sensitivity in metazoan, which correlate to correlate visual function and eye development. We studied Sof-rhodopsin expression during retina differentiation. By in situ hybridization, we show that (1) all of the RDGN genes, including Sof-pax6, are expressed in the eye area during the early developmental stages but they are not expressed in the retina, unlike Sof-otx, which could have a role in retina differentiation; (2) Sof-rhodopsin is expressed in the retina just before vision gets functional, from stage 23 to hatching. Our results evidence a role of Sof-six1/2, Sof-eya, and Sof-dac in eye development. However, the gene network involved in the retinal photoreceptor differentiation remains to be determined. Moreover, for the first time, Sof-rhodopsin expression is shown in the embryonic retina of cuttlefish suggesting the evolutionary conservation of the role of rhodopsin in visual phototransduction within metazoans. These findings are correlated with the physiological and behavioral observations suggesting that S. officinalis is able to react to light stimuli from stage 25 of organogenesis on, as soon as the first retinal pigments appear. PMID:28883798

Quasi-Elastic Light Scattering in Ophthalmology

NASA Astrophysics Data System (ADS)

Ansari, Rafat R.

The eye is not just a "window to the soul"; it can also be a "window to the human body." The eye is built like a camera. Light which travels from the cornea to the retina traverses through tissues that are representative of nearly every tissue type and fluid type in the human body. Therefore, it is possible to diagnose ocular and systemic diseases through the eye. Quasi-elastic light scattering (QELS) also known as dynamic light scattering (DLS) is a laboratory technique routinely used in the characterization of macromolecular dispersions. QELS instrumentation has now become more compact, sensitive, flexible, and easy to use. These developments have made QELS/DLS an important tool in ophthalmic research where disease can be detected early and noninvasively before the clinical symptoms appear.

Age-related differences in memory expression during infancy: using eye-tracking to measure relational memory in 6- and 12-month-olds.

PubMed

Richmond, Jenny L; Power, Jessica

2014-09-01

Relational memory, or the ability to bind components of an event into a network of linked representations, is a primary function of the hippocampus. Here we extend eye-tracking research showing that infants are capable of forming memories for the relation between arbitrarily paired scenes and faces, by looking at age-related changes in relational memory over the first year of life. Six- and 12-month-old infants were familiarized with pairs of faces and scenes before being tested with arrays of three familiar faces that were presented on a familiar scene. Preferential looking at the face that matches the scene is typically taken as evidence of relational memory. The results showed that while 6-month-old showed very early preferential looking when face/scene pairs were tested immediately, 12-month-old did not exhibit evidence of relational memory either immediately or after a short delay. Theoretical implications for the functional development of the hippocampus and practical implications for the use of eye tracking to measure memory during early life are discussed. © 2014 Wiley Periodicals, Inc.

[Anophthalmia and microphthalmia requires multidisciplinary care. Many of the children also have other medical problems].

PubMed

Jugård, Ylva; Odersjö, Marie; Topa, Alexandra; Lindgren, Gun; Andersson Grönlund, Marita

2015-07-13

Anophthalmia/microphthalmia (A/M) are rare congenital eye malformations. Early intervention with ocular prosthesis can stimulate orbital growth and prevent facial asymmetry. We reviewed medical records from 18 individuals with A/M (0.8-31 years) treated with ocular prosthesis at Sahlgrenska University Hospital between 2000 and 2012. A majority had other ocular findings. Seven had subnormal visual acuity in the fellow eye, one third were in contact with vision support services and half of the group wore glasses. Eleven individuals had extra-ocular findings such as cardiac defect, hearing impairment and neuropsychiatric disorders, possibly indicating syndromic conditions. We suggest that investigation of A/M children should include ultrasound of the eye, optionally visual evoked potential and magnetic resonance imaging of the CNS. The ophthalmologist should initiate treatment with prosthesis, pediatric assessment, hearing tests and genetic counseling, but should also monitor visual development of the fellow eye.

Eye tracking reveals a crucial role for facial motion in recognition of faces by infants.

PubMed

Xiao, Naiqi G; Quinn, Paul C; Liu, Shaoying; Ge, Liezhong; Pascalis, Olivier; Lee, Kang

2015-06-01

Current knowledge about face processing in infancy comes largely from studies using static face stimuli, but faces that infants see in the real world are mostly moving ones. To bridge this gap, 3-, 6-, and 9-month-old Asian infants (N = 118) were familiarized with either moving or static Asian female faces, and then their face recognition was tested with static face images. Eye-tracking methodology was used to record eye movements during the familiarization and test phases. The results showed a developmental change in eye movement patterns, but only for the moving faces. In addition, the more infants shifted their fixations across facial regions, the better their face recognition was, but only for the moving faces. The results suggest that facial movement influences the way faces are encoded from early in development. (c) 2015 APA, all rights reserved).

The 2014 Bowman Lecture—Bowman's and Bruch's: a tale of two membranes during the laser revolution

PubMed Central

Marshall, J

2015-01-01

To describe the historical evolution of the role of lasers in effecting therapeutic changes in the four acellular membranes of the eye. Over the past 50 years, iterative developments have been instituted in lasers used for various forms of eye surgery predominately on the basis of data generated in early experiments in the 1960s to determine thresholds for damage and their incorporation in codes of practice for laser safety. The evolutionary steps are described. Excimer laser technology resulted in the generation of the new field of laser refractive surgery with over 40 million individuals now having undergone procedures such as photorefractive keratectomy and LASIK. Developments in lasers used for various forms of retinal surgery have undergone changes involving shorter and shorter pulse durations together with changes in beam energy distribution with implications for potential intervention in AMD prophylactically. Lasers have made a major impact on surgical treatment on all four acellular membranes of the eye but particularly Bowman's membrane in refractive surgery, where it has been demonstrated that it can be removed without significant consequences for eye health or vision. PMID:25567376

Early Binocular Input Is Critical for Development of Audiovisual but Not Visuotactile Simultaneity Perception.

PubMed

Chen, Yi-Chuan; Lewis, Terri L; Shore, David I; Maurer, Daphne

2017-02-20

Temporal simultaneity provides an essential cue for integrating multisensory signals into a unified perception. Early visual deprivation, in both animals and humans, leads to abnormal neural responses to audiovisual signals in subcortical and cortical areas [1-5]. Behavioral deficits in integrating complex audiovisual stimuli in humans are also observed [6, 7]. It remains unclear whether early visual deprivation affects visuotactile perception similarly to audiovisual perception and whether the consequences for either pairing differ after monocular versus binocular deprivation [8-11]. Here, we evaluated the impact of early visual deprivation on the perception of simultaneity for audiovisual and visuotactile stimuli in humans. We tested patients born with dense cataracts in one or both eyes that blocked all patterned visual input until the cataractous lenses were removed and the affected eyes fitted with compensatory contact lenses (mean duration of deprivation = 4.4 months; range = 0.3-28.8 months). Both monocularly and binocularly deprived patients demonstrated lower precision in judging audiovisual simultaneity. However, qualitatively different outcomes were observed for the two patient groups: the performance of monocularly deprived patients matched that of young children at immature stages, whereas that of binocularly deprived patients did not match any stage in typical development. Surprisingly, patients performed normally in judging visuotactile simultaneity after either monocular or binocular deprivation. Therefore, early binocular input is necessary to develop normal neural substrates for simultaneity perception of visual and auditory events but not visual and tactile events. Copyright © 2017 Elsevier Ltd. All rights reserved.

Physiologic Inter-eye Differences in Monkey Optic Nerve Head Architecture and Their Relation to Changes in Early Experimental Glaucoma

PubMed Central

Yang, Hongli; Downs, J. Crawford; Burgoyne, Claude F.

2009-01-01

Purpose To characterize physiologic inter-eye differences in optic nerve head (ONH) architecture within six normal rhesus monkeys and compare them to inter-eye differences within three previously-reported cynomolgus monkeys with early experimental glaucoma (EEG). Methods Trephinated ONH and peripapillary sclera from both eyes of six normal monkeys were serial sectioned, 3D reconstructed, 3D delineated and parameterized. For each normal animal, and each parameter, physiologic inter-eye difference (PID) was calculated (both overall and regionally) by converting all OS data to OD configuration and subtracting the OS from the OD value and Physiologic Inter-eye Percent Difference (PIPD) was calculated as the PID divided by the measurement mean of the two eyes. For each EEG monkey, inter-eye (EEG minus normal) differences and percent differences for each parameter overall and regionally were compared to the PID and PIPD Maximums. Results For all parameters the PID Maximums were relatively small overall. Compared to overall PID maximums, overall inter-eye differences in EEG monkeys were greatest for laminar deformation and thickening, posterior scleral canal enlargement, cupping and prelaminar neural tissue thickening. Compared to the regional PID Maximums, the lamina cribrosa was posteriorly deformed centrally, inferiorly, inferonasally and superiorly and was thickened centrally. The prelaminar neural tissues were thickened inferiorly, inferonasally and superiorly. Conclusion These data provide the first characterization of PID/PIPD maximums for ONH neural and connective tissue parameters in normal monkeys and serve to further clarify the location and character of early ONH change in experimental glaucoma. However, because of the species differences, the findings in EEG need to be confirmed within EEG rhesus monkey eyes. PMID:18775866

Children's Ophthalmologic Problems.

ERIC Educational Resources Information Center

Robb, Richard M.

1977-01-01

The author points out the need for early screening for ophthalmologic disorders and reviews symptoms of various eye disorders. Among the types of eye pathology considered are retinoblastoma, retrolental fibroplasia, congenital glaucoma, congenital cataracts, congenital strabismus, chlamydia oculogenitalis, orbital cellulitis, and eye injuries.…

Unique Temporal Expression of Triplicated Long-Wavelength Opsins in Developing Butterfly Eyes

PubMed Central

Arikawa, Kentaro; Iwanaga, Tomoyuki; Wakakuwa, Motohiro; Kinoshita, Michiyo

2017-01-01

Following gene duplication events, the expression patterns of the resulting gene copies can often diverge both spatially and temporally. Here we report on gene duplicates that are expressed in distinct but overlapping patterns, and which exhibit temporally divergent expression. Butterflies have sophisticated color vision and spectrally complex eyes, typically with three types of heterogeneous ommatidia. The eyes of the butterfly Papilio xuthus express two green- and one red-absorbing visual pigment, which came about via gene duplication events, in addition to one ultraviolet (UV)- and one blue-absorbing visual pigment. We localized mRNAs encoding opsins of these visual pigments in developing eye disks throughout the pupal stage. The mRNAs of the UV and blue opsin are expressed early in pupal development (pd), specifying the type of the ommatidium in which they appear. Red sensitive photoreceptors first express a green opsin mRNA, which is replaced later by the red opsin mRNA. Broadband photoreceptors (that coexpress the green and red opsins) first express the green opsin mRNA, later change to red opsin mRNA and finally re-express the green opsin mRNA in addition to the red mRNA. Such a unique temporal and spatial expression pattern of opsin mRNAs may reflect the evolution of visual pigments and provide clues toward understanding how the spectrally complex eyes of butterflies evolved. PMID:29238294

Evaluating Glaucomatous Retinal Nerve Fiber Damage by GDx VCC Polarimetry in Taiwan Chinese Population

PubMed Central

Chen, Hsin-Yi; Huang, Mei-Ling; Huang, Wei-Cheng

2010-01-01

Purpose To study the capability of scanning laser polarimetry with variable corneal compensation (GDx VCC) to detect differences in retinal nerve fiber layer thickness between normal and glaucomatous eyes in a Taiwan Chinese population. Methods This study included 44 normal eyes and 107 glaucomatous eyes. The glaucomatous eyes were divided into three subgroups on the basis of its visual field defects (early, moderate, severe). Each subject underwent a GDx-VCC exam and visual field testing. The area under the receiver-operating characteristic curve (AROC) of each relevant parameter was used to differentiate normal from each glaucoma subgroup, respectively. The correlation between visual field index and each parameter was evaluated for the eyes in the glaucoma group. Results For normal vs. early glaucoma, the parameter with the best AROC was Nerve fiber indicator (NFI) (0.942). For normal vs. moderate glaucoma, the parameter showing the best AROC was NFI (0.985). For normal vs. severe glaucoma, the parameter that had the best AROC was NFI (1.000). For early vs. moderate glaucoma, the parameter with the best AROC was NFI (0.732). For moderate vs. severe, the parameter showing the best AROC was temporal-superior-nasal-inferior-temporal average (0.652). For early vs. severe, the parameter with the best AROC was NFI (0.852). Conclusions GDx-VCC-measured parameters may serve as a useful tool to distinguish normal from glaucomatous eyes; in particular, NFI turned out to be the best discriminating parameter.

The eye limits the brain's learning potential

PubMed Central

Zhou, Jiawei; Zhang, Yudong; Dai, Yun; Zhao, Haoxin; Liu, Rong; Hou, Fang; Liang, Bo; Hess, Robert F.; Zhou, Yifeng

2012-01-01

The concept of a critical period for visual development early in life during which sensory experience is essential to normal neural development is now well established. However recent evidence suggests that a limited degree of plasticity remains after this period and well into adulthood. Here, we ask the question, "what limits the degree of plasticity in adulthood?" Although this limit has been assumed to be due to neural factors, we show that the optical quality of the retinal image ultimately limits the brain potential for change. We correct the high-order aberrations (HOAs) normally present in the eye's optics using adaptive optics, and reveal a greater degree of neuronal plasticity than previously appreciated. PMID:22509464

Comparison of matrix frequency-doubling technology perimetry and standard automated perimetry in monitoring the development of visual field defects for glaucoma suspect eyes.

PubMed

Hu, Rongrong; Wang, Chenkun; Racette, Lyne

2017-01-01

Perimetry is indispensable for the clinical management of glaucoma suspects. Our goal is to compare the performance of standard automated perimetry (SAP) and Matrix frequency-doubling technology (FDT) perimetry in monitoring the development of visual field (VF) defects in glaucoma suspect eyes. Longitudinal data of paired SAP and FDT from 221 eyes of 155 glaucoma suspects enrolled in the Diagnostic Innovations in Glaucoma Study or the African Descent and Glaucoma Evaluation Study were included. All eyes had glaucomatous optic neuropathy or ocular hypertension, but normal SAP and FDT results at baseline. The development of glaucomatous VF defects was defined as the presence of a cluster of ≥ 3 (less conservative) or ≥ 4 (more conservative) locations confirmed on ≥ 2 additional consecutive tests. Risk factors for the development of VF defects were analyzed by COX proportional hazard models. After conversion into common logarithmic units, the rates of change of global VF indices were fitted with linear mixed models. FDT detected more eyes that developed VF defects than SAP using the less conservative criterion, and no significant difference was observed using the more conservative criterion. For those eyes detected by both SAP and FDT, FDT detected the development of VF defects either earlier than SAP or simultaneously in most cases. Baseline structural measurements were not significantly associated with an increased risk for the development of glaucomatous VF defects on either SAP or FDT. Older age was significantly associated with the development of VF defects on FDT but not on SAP. Both SAP and FDT detected a progressing worsening trend of pattern standard deviation over time with a similar rate of change between these test types. Matrix FDT would be useful to monitor the onset of VF defects in glaucoma suspects and may outperform SAP in the early stage of glaucomatous VF damage.

Biochemical Measurements of Free Opsin in Macular Degeneration Eyes: Examining the 11-CIS Retinal Deficiency Hypothesis of Delayed Dark Adaptation (An American Ophthalmological Society Thesis).

PubMed

Hanneken, Anne; Neikirk, Thomas; Johnson, Jennifer; Kono, Masahiro

2017-08-01

To test the hypothesis that delayed dark adaptation in patients with macular degeneration is due to an excess of free unliganded opsin (apo-opsin) and a deficiency of the visual chromophore, 11 -cis retinal, in rod outer segments. A total of 50 human autopsy eyes were harvested from donors with and without macular degeneration within 2-24 hrs. postmortem. Protocols were developed which permitted dark adaptation of normal human eyes after death and enucleation. Biochemical methods of purifying rod outer segments were optimized and the concentration of rhodopsin and apo-opsin was measured with UV-visible scanning spectroscopy. The presence of apo-opsin was calculated by measuring the difference in the rhodopsin absorption spectra before and after the addition of 11 -cis retinal. A total of 20 normal eyes and 16 eyes from donors with early, intermediate and advanced stages of macular degeneration were included in the final analysis. Dark adaptation was achieved by harvesting whole globes in low light, transferring into dark (light-proof) canisters and dissecting the globes using infrared light and image converters for visualization. Apo-opsin was readily detected in positive controls after the addition of 11 -cis retinal. Normal autopsy eyes showed no evidence of apo-opsin. Eyes with macular degeneration also showed no evidence of apo-opsin, regardless of the severity of disease. Methods have been developed to study dark adaptation in human autopsy eyes. Eyes with age-related macular degeneration do not show a deficiency of 11 -cis retinal or an excess of apo-opsin within rod outer segments.

Determinants of Utilization of Eye Care Services in a Rural Adult Population of a Developing Country

PubMed Central

Olusanya, Bolutife A.; Ashaye, Adeyinka O.; Owoaje, Eme T.; Baiyeroju, Aderonke M.; Ajayi, Benedictus G.

2016-01-01

Purpose: To describe the factors that determine the utilization of eye care services in a rural community in South-Western Nigeria. Methods: A descriptive cross-sectional survey using a multistage sampling technique was conducted. The main outcome measure was self-reported previous consultation of an orthodox medical facility for eye care. Results: The study sample included 643 participants. Only 122 (19%) respondents had previously visited orthodox facilities in search of eye care and 24% of those with presenting visual acuity <6/18 had sought eye care. Characteristics associated with previous utilization of eye care services were age of =70 years (odds ratio [OR] ≥ 1.7, P = 0.02); male gender (OR = 1.5, P = 0.04); literacy (OR = 1.7, P = 0.007); and residing close to an eye care facility (OR = 2.8, P < 0.001). Blind respondents were three times more likely to seek eye care (P < 0.001). Regression analysis revealed that factors associated with increased likelihood of utilization of eye care services included age ≥70 years; literacy; residence close to an eye facility; being diabetic or hypertensive; history of ocular symptoms, and blindness. Conclusions: These findings suggest that a significant proportion (75%) of adults in the study area are not utilizing eye care services and that blindness is an important determinant of utilization of eye care services. Health education and awareness campaigns about the importance and benefits of seeking eye care early, and the provision of community-based eye care programs are essential to boost the uptake of eye care services in this community as well as other rural areas of West Africa. PMID:26957847

Microaneurysm turnover is a predictor of diabetic retinopathy progression.

PubMed

Pappuru, Rajeev K R; Ribeiro, Luísa; Lobo, Conceição; Alves, Dalila; Cunha-Vaz, José

2018-04-26

To analyse retinopathy phenotypes and microaneurysm (MA) turnover in mild non-proliferative diabetic retinopathy (NPDR) as predictors of progression to diabetic central-involved macular oedema (CIMO) in patients with type 2 diabetes mellitus (DM) in two different ethnic populations. 205 patients with type 2 DM and mild NPDR were followed in a prospective observational study for 2 years or until development of CIMO, in two centres from different regions of the world. Ophthalmological examinations, including best-corrected visual acuity (BCVA), fundus photography with RetmarkerDR analysis, and optical coherence tomography (OCT), were performed at baseline and 6 12 and 24 months. 158 eyes/patients reached either the study endpoint, CIMO (24) or performed the last study visit (24-month visit) without developing CIMO (134). From the eyes/patients in analysis, 27 eyes (17.1%) progressed to more advanced ETDRS (Early Treatment Diabetic Retinopathy Study) levels: 6 progressed to mild NPDR (level 35), 15 progressed to moderate NPDR (level 43), 5 progressed to moderately severe NPDR (level 47) and 1 progressed to high risk PDR (level 71). Worsening in ETDRS level is associated with phenotype C (p=0.005). From the 130 eyes/patients with a low MA turnover, 18 (13.8%) eyes/patients had an increase in ETDRS level, and from the 19 eyes/patients with a high MA turnover, 9 (47.4%) had an increase in ETDRS level (p<0.001). Eyes in the initial stages of diabetic retinopathy show different phenotypes with different risks for progression to CIMO. In phenotype C, MA turnover correlates with ETDRS grading worsening and development of CIMO. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Deletion of OTX2 in neural ectoderm delays anterior pituitary development

PubMed Central

Mortensen, Amanda H.; Schade, Vanessa; Lamonerie, Thomas; Camper, Sally A.

2015-01-01

OTX2 is a homeodomain transcription factor that is necessary for normal head development in mouse and man. Heterozygosity for loss-of-function alleles causes an incompletely penetrant, haploinsufficiency disorder. Affected individuals exhibit a spectrum of features that range from developmental defects in eye and/or pituitary development to acephaly. To investigate the mechanism underlying the pituitary defects, we used different cre lines to inactivate Otx2 in early head development and in the prospective anterior and posterior lobes. Mice homozygous for Otx2 deficiency in early head development and pituitary oral ectoderm exhibit craniofacial defects and pituitary gland dysmorphology, but normal pituitary cell specification. The morphological defects mimic those observed in humans and mice with OTX2 heterozygous mutations. Mice homozygous for Otx2 deficiency in the pituitary neural ectoderm exhibited altered patterning of gene expression and ablation of FGF signaling. The posterior pituitary lobe and stalk, which normally arise from neural ectoderm, were extremely hypoplastic. Otx2 expression was intact in Rathke's pouch, the precursor to the anterior lobe, but the anterior lobe was hypoplastic. The lack of FGF signaling from the neural ectoderm was sufficient to impair anterior lobe growth, but not the differentiation of hormone-producing cells. This study demonstrates that Otx2 expression in the neural ectoderm is important intrinsically for the development of the posterior lobe and pituitary stalk, and it has significant extrinsic effects on anterior pituitary growth. Otx2 expression early in head development is important for establishing normal craniofacial features including development of the brain, eyes and pituitary gland. PMID:25315894

Pattern of Expression of p53, Its Family Members, and Regulators during Early Ocular Development and in the Post-Mitotic Retina

PubMed Central

Vuong, Linda; Brobst, Daniel E.; Saadi, Anisse; Ivanovic, Ivana; Al-Ubaidi, Muayyad R.

2012-01-01

Purpose. Because of its role in cell cycle regulation and apoptosis, p53 may be involved in maintaining the post-mitotic state of the adult eye. To shed light on the role of p53 in retinal development and maintenance, this study investigated the pattern of expression of p53, its family members, and its regulators during the development of the mouse eye. Methods. Relative quantitative real-time PCR (qRT-PCR) was used to determine the steady-state levels of target transcripts in RNA extracted from wild-type mouse whole eyes or retinas between embryonic day (E) 15 and post-natal day (P) 30. Immunoblotting was used to compare the steady-state levels of the protein to that of the transcript. Results. Transcript and protein levels for p53 in the eye were highest at E17 and E18, respectively. However, both p53 transcript and protein levels dropped precipitously thereafter, and no protein was detected on immunoblots after P3. Expression patterns of p63, p73, Mdm2, Mdm4, and Yy1 did not follow that of p53. Immunohistochemistry analysis of the developing eye showed that both p53 and Mdm2 are abundantly expressed at E18 in all layers of the retinal neuroblast. Conclusions. Downregulation of p53 in the post-mitotic retina suggests that, although p53 may be involved in ocular and retinal development, it may play a minimal role in healthy adult retinal function. PMID:22714890

Rotating Scheimpflug Imaging Indices in Different Grades of Keratoconus

PubMed Central

2016-01-01

Purpose. To evaluate accuracy of various Keratoconus (KC) screening indices, in relation to Topographic Keratoconus (TKC) grading. Setting. Al Watany Eye Hospital, Cairo, Egypt. Methods. Data of 103 normal (group 1) and 73 KC eyes (group 2), imaged by Pentacam (branded as Allegro Oculyzer), were analysed. Group 2 was divided into 2a: 14 eyes (TKC = 1, early KC), 2b: 25 eyes (TKC = 1 to 2 or 2, moderate KC), and 2c: 34 eyes (TKC = 2 to 3 up to 4, severe KC). Participants were followed up for six years to confirm diagnosis. Area under the receiver operating characteristic curve (AUROC) was calculated for evaluated curvature, elevation, and pachymetry indices with various reference shapes at different diameters. Results. When comparing normal to KC eyes, ten indices had significantly higher AUROC. Only five of them had significantly higher AUROC in early KC compared to normal corneas: Pachymetry Progression Index- (PPI-) Maximum (Max), Ambrósio's Relational Thickness- (ART-) Max, PPI-Max minus PPI-Minimum (Min), central corneal thickness (CCT), and diagonal decentration of thinnest point from the apex (AUROC = 0.690, 0.690, 0.687, 0.683, and 0.674, resp.). Conclusion. Generally, ten pachymetry and elevation-based indices had significantly higher AUROC. Five indices had statistically significant high AUROC when comparing early KC to normal corneas. PMID:27579178

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

PubMed

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

2017-04-01

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

Ophthalmic Diagnostics Using a New Dynamic Light Scattering Fiber Optic Probe

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.; Suh, Kwang I.; Dellavecchia, Michael A.; Dubin, Stephen

1995-01-01

A new fiber optic probe is developed to study different parts of the eye. The probe positioned in front of an eye, delivers a low power light from a laser diode into the eye and guides the light which is back scattered by different components (aqueous humor, lens, and vitreous humor) of the eye through a receiving optical fiber to a photo detector. The probe provides rapid determination of macromolecular diffusivities and their respective size distributions in the eye lens and the gel-like material in the vitreous humor. We report alpha-crystalline size distributions, as a function of penetration depth, inside the lens and hyaluronic acid molecular size distribution in the vitreous body. In a clinical setting, the probe can be mounted on a slit-lamp apparatus simply by using a H-ruby lens holder. The capability of detecting cataracts, both nuclear and peripheral, in their early stages of formation, in a non invasive and quantitative fashion, has the potential in patient monitoring and in developing and testing new drugs or diet therapies to 'dissolve' or slow down the cataract formation before surgery is necessary. The ability to detect biochemical and macromolecular changes in the vitreous structure can be very useful in identifying certain diseases of the posterior chamber, e.g., posterior vitreous detachment.

Intraocular (Eye) Melanoma—Patient Version

Cancer.gov

Intraocular (uveal) melanoma is a rare cancer that forms in the eye. It usually has no early signs or symptoms. As with melanoma of the skin, risk factors include having fair skin and light-colored eyes. Start here to find information on intraocular melanoma treatment.

Ultra-wide-field scanning laser ophthalmoscopy assists in the clinical detection and evaluation of asymptomatic early-stage familial exudative vitreoretinopathy.

PubMed

Lyu, Jiao; Zhang, Qi; Wang, Shi-Yuan; Chen, Yi-Ye; Xu, Yu; Zhao, Pei-Quan

2017-01-01

This study aims to investigate the ability of the ultra-wide-field scanning laser ophthalmoscope (UWF SLO) in clinically detecting and evaluating asymptomatic early-stage familial exudative vitreoretinopathy (FEVR). We retrospectively reviewed 163 eyes of 83 asymptomatic family members of 48 patients with FEVR. UWF SLO imaging (Optos® PLC, Scotland, UK) was performed on asymptomatic family members as a preliminary screening test for fundus anomalies, and the findings were compared with subsequent examinations using indirect fundus ophthalmoscopy in full mydriasis, fluorescein angiography (FA), fundus autoflourescence, and genetic sequencing. A total of 86 eyes of 43 asymptomatic family members were clinically diagnosed with early-stage FEVR, and 17 of the affected 43 family members were also genetically diagnosed. Compared with FA as a standard, the UWF SLO was highly effective in diagnosing FEVR with a sensitivity and specificity of 93.0 % and 97.5 %, respectively. The UWF SLO was able to diagnose early-stage FEVR in 93.0 % of eyes, and guided the selection of therapies in 46.5 % of the eyes studied. UWF SLO is a valuable imaging tool for detecting fundus anomalies related to early-stage FEVR, and this tool can assist in the clinical diagnosis and evaluation of early-stage FEVR in asymptomatic family members of patients with FEVR.

Emergence of order in visual system development.

PubMed Central

Shatz, C J

1996-01-01

Neural connections in the adult central nervous system are highly precise. In the visual system, retinal ganglion cells send their axons to target neurons in the lateral geniculate nucleus (LGN) in such a way that axons originating from the two eyes terminate in adjacent but nonoverlapping eye-specific layers. During development, however, inputs from the two eyes are intermixed, and the adult pattern emerges gradually as axons from the two eyes sort out to form the layers. Experiments indicate that the sorting-out process, even though it occurs in utero in higher mammals and always before vision, requires retinal ganglion cell signaling; blocking retinal ganglion cell action potentials with tetrodotoxin prevents the formation of the layers. These action potentials are endogenously generated by the ganglion cells, which fire spontaneously and synchronously with each other, generating "waves" of activity that travel across the retina. Calcium imaging of the retina shows that the ganglion cells undergo correlated calcium bursting to generate the waves and that amacrine cells also participate in the correlated activity patterns. Physiological recordings from LGN neurons in vitro indicate that the quasiperiodic activity generated by the retinal ganglion cells is transmitted across the synapse between ganglion cells to drive target LGN neurons. These observations suggest that (i) a neural circuit within the immature retina is responsible for generating specific spatiotemporal patterns of neural activity; (ii) spontaneous activity generated in the retina is propagated across central synapses; and (iii) even before the photoreceptors are present, nerve cell function is essential for correct wiring of the visual system during early development. Since spontaneously generated activity is known to be present elsewhere in the developing CNS, this process of activity-dependent wiring could be used throughout the nervous system to help refine early sets of neural connections into their highly precise adult patterns. Images Fig. 1 Fig. 4 PMID:8570602

He Opened His Eyes and Smiled.

ERIC Educational Resources Information Center

Dixon, Harrison A.

1989-01-01

A father relates his family's efforts to provide early stimulation to a son diagnosed with cerebral palsy and visual impairments. As the boy developed, he listened to audiotape recordings of music and nursery rhymes, explored household objects, watched television, played computer games, and was eventually enrolled in a mainstreamed kindergarten.…

Infants Generate Goal-Based Action Predictions

ERIC Educational Resources Information Center

Cannon, Erin N.; Woodward, Amanda L.

2012-01-01

Predicting the actions of others is critical to smooth social interactions. Prior work suggests that both understanding and anticipation of goal-directed actions appears early in development. In this study, on-line goal prediction was tested explicitly using an adaptation of Woodward's (1998) paradigm for an eye-tracking task. Twenty 11-month-olds…

Asymmetrical Interhemispheric Connections Develop in Cat Visual Cortex after Early Unilateral Convergent Strabismus: Anatomy, Physiology, and Mechanisms

PubMed Central

Bui Quoc, Emmanuel; Ribot, Jérôme; Quenech’Du, Nicole; Doutremer, Suzette; Lebas, Nicolas; Grantyn, Alexej; Aushana, Yonane; Milleret, Chantal

2011-01-01

In the mammalian primary visual cortex, the corpus callosum contributes to the unification of the visual hemifields that project to the two hemispheres. Its development depends on visual experience. When this is abnormal, callosal connections must undergo dramatic anatomical and physiological changes. However, data concerning these changes are sparse and incomplete. Thus, little is known about the impact of abnormal postnatal visual experience on the development of callosal connections and their role in unifying representation of the two hemifields. Here, the effects of early unilateral convergent strabismus (a model of abnormal visual experience) were fully characterized with respect to the development of the callosal connections in cat visual cortex, an experimental model for humans. Electrophysiological responses and 3D reconstruction of single callosal axons show that abnormally asymmetrical callosal connections develop after unilateral convergent strabismus, resulting from an extension of axonal branches of specific orders in the hemisphere ipsilateral to the deviated eye and a decreased number of nodes and terminals in the other (ipsilateral to the non-deviated eye). Furthermore this asymmetrical organization prevents the establishment of a unifying representation of the two visual hemifields. As a general rule, we suggest that crossed and uncrossed retino-geniculo-cortical pathways contribute successively to the development of the callosal maps in visual cortex. PMID:22275883

Early detection of glaucoma by means of a novel 3D computer‐automated visual field test

PubMed Central

Nazemi, Paul P; Fink, Wolfgang; Sadun, Alfredo A; Francis, Brian; Minckler, Donald

2007-01-01

Purpose A recently devised 3D computer‐automated threshold Amsler grid test was used to identify early and distinctive defects in people with suspected glaucoma. Further, the location, shape and depth of these field defects were characterised. Finally, the visual fields were compared with those obtained by standard automated perimetry. Patients and methods Glaucoma suspects were defined as those having elevated intraocular pressure (>21 mm Hg) or cup‐to‐disc ratio of >0.5. 33 patients and 66 eyes with risk factors for glaucoma were examined. 15 patients and 23 eyes with no risk factors were tested as controls. The recently developed 3D computer‐automated threshold Amsler grid test was used. The test exhibits a grid on a computer screen at a preselected greyscale and angular resolution, and allows patients to trace those areas on the grid that are missing in their visual field using a touch screen. The 5‐minute test required that the patients repeatedly outline scotomas on a touch screen with varied displays of contrast while maintaining their gaze on a central fixation marker. A 3D depiction of the visual field defects was then obtained that was further characterised by the location, shape and depth of the scotomas. The exam was repeated three times per eye. The results were compared to Humphrey visual field tests (ie, achromatic standard or SITA standard 30‐2 or 24‐2). Results In this pilot study 79% of the eyes tested in the glaucoma‐suspect group repeatedly demonstrated visual field loss with the 3D perimetry. The 3D depictions of visual field loss associated with these risk factors were all characteristic of or compatible with glaucoma. 71% of the eyes demonstrated arcuate defects or a nasal step. Constricted visual fields were shown in 29% of the eyes. No visual field changes were detected in the control group. Conclusions The 3D computer‐automated threshold Amsler grid test may demonstrate visual field abnormalities characteristic of glaucoma in glaucoma suspects with normal achromatic Humphrey visual field testing. This test may be used as a screening tool for the early detection of glaucoma. PMID:17504855

Neuro-ophthalmologic aspects of multiple sclerosis: Using eye movements as a clinical and experimental tool

PubMed Central

Niestroy, Annette; Rucker, Janet C; Leigh, R John

2007-01-01

Ocular motor disorders are a well recognized feature of multiple sclerosis (MS). Clinical abnormalities of eye movements, early in the disease course, are associated with generalized disability, probably because the burden of disease in affected patients falls on the brainstem and cerebellar pathways, which are important for gait and balance. Measurement of eye movements, especially when used to detect internuclear ophthalmoplegia (INO), may aid diagnosis of MS. Measurement of the ocular following response to moving sinusoidal gratings of specified spatial frequency and contrast can be used as an experimental tool to better understand persistent visual complaints in patients who have suffered optic neuritis. Patients with MS who develop acquired pendular nystagmus often benefit from treatment with gabapentin or memantine. PMID:19668480

Nerve fibre layer analysis with GDx with a variable corneal compensator in patients with multiple sclerosis.

PubMed

Della Mea, Giovanni; Bacchetti, Sonia; Zeppieri, Marco; Brusini, Paolo; Cutuli, Daniela; Gigli, Gian Luigi

2007-01-01

To evaluate the ability of GDx with variable corneal compensator (VCC) compared to visual-evoked potentials (VEPs) and standard automated perimetry (SAP) in the detection of early optic nerve damage in patients with multiple sclerosis (MS). 46 eyes of 23 MS patients were included. Ten of them had a history of acute retrobulbar optic neuritis. A control group of 20 normal subjects was also included. All subjects underwent a complete ophthalmological examination and testing with SAP, GDx VCC and VEPs. 19 eyes (41.3%) were abnormal with GDx VCC compared to 38 eyes (82.6%) with SAP and 31 (64.4%) with VEPs. In the optic neuritis group, 9 eyes (69.2%) had optic nerve pallor; SAP was abnormal in 8 of these eyes (61.5%) while VEPs and GDx VCC were abnormal in 6 eyes (46.1%). 2/20 eyes (10.0%) in the control group gave a false-positive abnormal result with SAP. GDx VCC and VEP were normal for all the eyes in the control group. GDx VCC is less able to detect early defects in MS patients compared to the currently used standard techniques of SAP and VEPs. Copyright (c) 2007 S. Karger AG, Basel.

Non-Invasive Evaluation of Corneal Abnormalities Using Static and Dynamic Light Scattering

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.; Misra, Anup K.; Leung, Alfred B.; King, James F.; Datiles, Manuel B., III

2002-01-01

A preliminary study of corneal abnormalities in intact bovine eyes is presented. Twenty-one eyes were treated with chemicals, cotton swabs, and radial and photo-refractive surgeries. Dynamic and static light scattering was performed as a function of the penetration depth into the corneal tissue. Topographical maps of corneal refractive power from untreated and treated corneas were also obtained using videokeratoscopy and results compared. The ultimate aim is to develop the technique of dynamic light scattering (DLS) for clinical applications in early evaluation of corneal complications after laser-assisted in situ keratomileusis (LASIK) surgeries and other corneal abnormalities.

Noninvasive evaluation of corneal abnormalities using static and dynamic light scattering

NASA Astrophysics Data System (ADS)

Ansari, Rafat R.; Misra, Anup K.; Leung, Alfred B.; King, James F.; Datiles, Manuel B., III

2002-06-01

A preliminary study of corneal abnormalities in intact bovine eyes is presented. Twenty-one eyes were treated with chemicals, cotton swabs, and radial and photo-refractive surgeries. Dynamic and static light scattering was performed as a function of the penetration depth into the corneal tissue. Topographical maps of corneal refractive power from untreated and treated corneas were also obtained using videokeratoscopy and results compared. The ultimate aim is to develop the technique of dynamic light scattering (DLS) for clinical applications in early evaluation of corneal complications after laser-assisted in situ keratomileusis (LASIK) surgeries and other corneal abnormalities.

Detection of Early Loss of Color Vision in Age-Related Macular Degeneration - With Emphasis on Drusen and Reticular Pseudodrusen.

PubMed

Vemala, Roopa; Sivaprasad, Sobha; Barbur, John L

2017-05-01

To evaluate chromatic sensitivity in patients with age-related macular degeneration (AMD) characterized by drusen and reticular pseudodrusen. To investigate whether the severity of color vision loss can distinguish between various stages of AMD and hence be used as an index of progression toward advanced AMD. Chromatic sensitivity was measured by using the Color Assessment and Diagnosis (CAD) test in asymptomatic individuals with early and intermediate AMD and compared to normative data. All study participants had logMAR visual acuity of 0.3 or better. The CAD thresholds measured in eyes with and without reticular pseudodrusen were also compared and related to central macular thickness (CMT). Student's t-test P values < 0.05 were considered significant. All early- and intermediate-AMD eyes (n = 90) had chromatic sensitivity loss in either RG (red/green) or YB (yellow/blue), or both (P < 0.0001) as compared to age-matched normal subjects. The eyes exhibited a range of CAD thresholds affecting both color mechanisms, but YB color thresholds were in general higher than RG thresholds (P < 0.001). Intermediate-AMD patients exhibited large intersubject variability. In general, eyes with reticular pseudodrusen and eyes with CMT < 200 μm had significantly higher CAD thresholds. The anatomic integrity of cone photoreceptors remains relatively unaffected in early and intermediate stages of AMD. The processing of cone signals in the retina can, however, be heavily disrupted with subsequent loss of both YB and RG chromatic sensitivity. The greatest losses were observed in eyes with reticular pseudodrusen.

The early-stage diagnosis of albinic embryos by applying optical coherence tomography

NASA Astrophysics Data System (ADS)

Yang, Bor-Wen; Wang, Shih-Yuan; Wang, Yu-Yen; Cai, Jyun-Jhang; Chang, Chung-Hao

2013-09-01

Albinism is a kind of congenital disease of abnormal metabolism. Poecilia reticulata (guppy fish) is chosen as the model to study the development of albinic embryos as it is albinic, ovoviviparous and with short life period. This study proposed an imaging method for penetrative embryo investigation using optical coherence tomography. By imaging through guppy mother’s reproduction purse, we found the embryo’s eyes were the early-developed albinism features. As human’s ocular albinism typically appear at about four weeks old, it is the time to determine if an embryo will grow into an albino.

[Comparison of Discriminant Analysis and Decision Trees for the Detection of Subclinical Keratoconus].

PubMed

Kleinhans, Sonja; Herrmann, Eva; Kohnen, Thomas; Bühren, Jens

2017-08-15

Background Iatrogenic keratectasia is one of the most dreaded complications of refractive surgery. In most cases, keratectasia develops after refractive surgery of eyes suffering from subclinical stages of keratoconus with few or no signs. Unfortunately, there has been no reliable procedure for the early detection of keratoconus. In this study, we used binary decision trees (recursive partitioning) to assess their suitability for discrimination between normal eyes and eyes with subclinical keratoconus. Patients and Methods The method of decision tree analysis was compared with discriminant analysis which has shown good results in previous studies. Input data were 32 eyes of 32 patients with newly diagnosed keratoconus in the contralateral eye and preoperative data of 10 eyes of 5 patients with keratectasia after laser in-situ keratomileusis (LASIK). The control group was made up of 245 normal eyes after LASIK and 12-month follow-up without any signs of iatrogenic keratectasia. Results Decision trees gave better accuracy and specificity than did discriminant analysis. The sensitivity of decision trees was lower than the sensitivity of discriminant analysis. Conclusion On the basis of the patient population of this study, decision trees did not prove to be superior to linear discriminant analysis for the detection of subclinical keratoconus. Georg Thieme Verlag KG Stuttgart · New York.

Image projection optical system for measuring pattern electroretinograms

NASA Astrophysics Data System (ADS)

Starkey, Douglas E.; Taboada, John; Peters, Daniel

1994-06-01

The use of the pattern-electroretinogram (PERG) as a noninvasive diagnostic tool for the early detection of glaucoma has been supported by a number of recent studies. We have developed a unique device which uses a laser interferometer to generate a sinusoidal fringe pattern that is presented to the eye in Maxwellian view for the purpose of producing a PERG response. The projection system stimulates a large visual field and is designed to bypass the optics of the eye in order to measure the true retinal response to a temporally alternating fringe pattern. The contrast, spatial frequency, total power output, orientation, alternating temporal frequency, and field location of the fringe pattern presented to the eye can all be varied by the device. It is critical for these parameters to be variable so that optimal settings may be determined for the normal state and any deviation from it, i.e. early or preclinical glaucoma. Several interferometer designs and optical projection systems were studied in order to design a compact system which provided the desired variable pattern stimulus to the eye. This paper will present a description of the clinical research instrument and its performance with the primary emphasis on the optical system design as it relates to the fringe pattern generation and other optical parameters. Examples of its use in the study of glaucoma diagnosis will also be presented.

The selective disruption of spatial working memory by eye movements

PubMed Central

Postle, Bradley R.; Idzikowski, Christopher; Sala, Sergio Della; Logie, Robert H.; Baddeley, Alan D.

2005-01-01

In the late 1970s/early 1980s, Baddeley and colleagues conducted a series of experiments investigating the role of eye movements in visual working memory. Although only described briefly in a book (Baddeley, 1986), these studies have influenced a remarkable number of empirical and theoretical developments in fields ranging from experimental psychology to human neuropsychology to nonhuman primate electrophysiology. This paper presents, in full detail, three critical studies from this series, together with a recently performed study that includes a level of eye movement measurement and control that was not available for the older studies. Together, the results demonstrate several facts about the sensitivity of visuospatial working memory to eye movements. First, it is eye movement control, not movement per se, that produces the disruptive effects. Second, these effects are limited to working memory for locations, and do not generalize to visual working memory for shapes. Third, they can be isolated to the storage/maintenance components of working memory (e.g., to the delay period of the delayed-recognition task). These facts have important implications for models of visual working memory. PMID:16556561

Ocular pathology in melanomatous Sinclair miniature swine.

PubMed Central

Feeney-Burns, L.; Burns, R. P.; Gao, C. L.

1988-01-01

Eyes of cutaneous melanoma-bearing miniature Sinclair swine were examined by light and electron microscopy during growth and maturation of animals. The histology of ocular depigmentation, which occurs during melanoma arrest and skin depigmentation, was studied in eyes of animals that had successful and unsuccessful tumor regression. In 12 animals one eye was removed at an early stage and the second eye at a later stage of disease or maturation. The histologic and clinical course of the ocular changes was correlated with changes in the cutaneous tumors. Animals showing rapid cutaneous tumor regression developed acute uveitis that was characterized by an influx of mononuclear cells into the stroma of the ciliary body; later this spread to the iris and choroid. In late stages the cornea sometimes developed a band of calcium precipitates beneath the basal epithelial cells (band keratopathy). Uveal melanocytes developed watery cytoplasm typical of cells with ruptured plasma membranes. Released melanin granules were taken up initially into the lysosomal compartment of mononuclear cells having the various morphologic features of lymphocytes and monocytes; later, melanin also appeared in fibrocyte lysosomes. The relationship of these processes to various cell-mediated immunity phenomena is being studied. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 PMID:3354645

A PC-based shutter glasses controller for visual stimulation using multithreading in LabWindows/CVI.

PubMed

Gramatikov, Ivan; Simons, Kurt; Guyton, David; Gramatikov, Boris

2017-05-01

Amblyopia, commonly known as "lazy eye," is poor vision in an eye from prolonged neurologic suppression. It is a major public health problem, afflicting up to 3.6% of children, and will lead to lifelong visual impairment if not identified and treated in early childhood. Traditional treatment methods, such as occluding or penalizing the good eye with eye patches or blurring eye drops, do not always yield satisfactory results. Newer methods have emerged, based on liquid crystal shutter glasses that intermittently occlude the better eye, or alternately occlude the two eyes, thus stimulating vision in the "lazy" eye. As yet there is no technology that allows easy and efficient optimization of the shuttering characteristics for a given individual. The purpose of this study was to develop an inexpensive, computer-based system to perform liquid crystal shuttering in laboratory and clinical settings to help "wake up" the suppressed eye in amblyopic patients, and to help optimize the individual shuttering parameters such as wave shape, level of transparency/opacity, frequency, and duty cycle of the shuttering. We developed a liquid crystal glasses controller connected by USB cable to a PC computer. It generates the voltage waveforms going to the glasses, and has potentiometer knobs for interactive adjustments by the patient. In order to achieve good timing performance in this bidirectional system, we used multithreading programming techniques with data protection, implemented in LabWindows/CVI. The hardware and software developed were assessed experimentally. We achieved an accuracy of ±1Hz for the frequency, and ±2% for the duty cycle of the occlusion pulses. We consider these values to be satisfactory for the purpose of optimizing the visual stimulation by means of shutter glasses. The system can be used for individual optimization of shuttering attributes by clinicians, for training sessions in clinical settings, or even at home, aimed at stimulating vision in the "lazy" eye. Multithreading offers significant benefits for data acquisition and instrument control, making it possible to implement time-efficient algorithms in inexpensive yet versatile medical instrumentation with only minimum requirements on the hardware. Copyright © 2017 Elsevier B.V. All rights reserved.

Expansions of the Neurovascular Scleral Canal and Contained Optic Nerve Occur Early in the Hypertonic Saline Rat Experimental Glaucoma Model

PubMed Central

Pazos, Marta; Yang, Hongli; Gardiner, Stuart K.; Cepurna, W.O.; Johnson, E.C.; Morrison, J.C.; Burgoyne, Claude F.

2015-01-01

Purpose To characterize early optic nerve head (ONH) structural change in rat experimental glaucoma (EG). Methods Unilateral intraocular pressure (IOP) elevation was induced in Brown Norway rats by hypertonic saline injection into the episcleral veins and animals were sacrificed 4 weeks later by perfusion fixation. Optic nerve cross-sections were graded from 1 (normal) to 5 (extensive injury) by 5 masked observers. ONH’s with peripapillary retina and sclera were embedded, serial sectioned, 3-D reconstructed, delineated, and quantified. Overall and animal-specific EG versus Control eye ONH parameter differences were assessed globally and regionally by linear mixed effect models with significance criteria adjusted for multiple comparisons. Results Expansions of the optic nerve and surrounding anterior scleral canal opening achieved statistical significance overall (p<.0022), and in 7 of 8 EG eyes (p<.005). In at least 5 EG eyes, significant expansions (p<.005) in Bruch’s membrane opening (range 3–10%), the anterior and posterior scleral canal openings (8–21% and 5–21%, respectively), and the optic nerve at the anterior and posterior scleral canal openings (11–30% and 8–41%, respectively) were detected. Optic nerve expansion was greatest within the superior and inferior quadrants. Optic nerve expansion at the posterior scleral canal opening was significantly correlated to optic nerve damage (R= 0.768, P=.042). Conclusion In the rat ONH, the optic nerve and surrounding Bruch’s membrane opening and neurovascular scleral canal expand early in their response to chronic experimental IOP elevation. These findings provide phenotypic landmarks and imaging targets for detecting the development of experimental glaucomatous optic neuropathy in the rat eye. PMID:26500195

Expansions of the neurovascular scleral canal and contained optic nerve occur early in the hypertonic saline rat experimental glaucoma model.

PubMed

Pazos, Marta; Yang, Hongli; Gardiner, Stuart K; Cepurna, William O; Johnson, Elaine C; Morrison, John C; Burgoyne, Claude F

2016-04-01

To characterize early optic nerve head (ONH) structural change in rat experimental glaucoma (EG). Unilateral intraocular pressure (IOP) elevation was induced in Brown Norway rats by hypertonic saline injection into the episcleral veins and animals were sacrificed 4 weeks later by perfusion fixation. Optic nerve cross-sections were graded from 1 (normal) to 5 (extensive injury) by 5 masked observers. ONHs with peripapillary retina and sclera were embedded, serial sectioned, 3-D reconstructed, delineated, and quantified. Overall and animal-specific EG versus Control eye ONH parameter differences were assessed globally and regionally by linear mixed effect models with significance criteria adjusted for multiple comparisons. Expansions of the optic nerve and surrounding anterior scleral canal opening achieved statistical significance overall (p < 0.0022), and in 7 of 8 EG eyes (p < 0.005). In at least 5 EG eyes, significant expansions (p < 0.005) in Bruch's membrane opening (BMO) (range 3-10%), the anterior and posterior scleral canal openings (8-21% and 5-21%, respectively), and the optic nerve at the anterior and posterior scleral canal openings (11-30% and 8-41%, respectively) were detected. Optic nerve expansion was greatest within the superior and inferior quadrants. Optic nerve expansion at the posterior scleral canal opening was significantly correlated to optic nerve damage (R = 0.768, p = 0.042). In the rat ONH, the optic nerve and surrounding BMO and neurovascular scleral canal expand early in their response to chronic experimental IOP elevation. These findings provide phenotypic landmarks and imaging targets for detecting the development of experimental glaucomatous optic neuropathy in the rat eye. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of Perfused Foveal Microvascular Density and Identification of Nonperfused Capillaries in Healthy and Vasculopathic Eyes

PubMed Central

Pinhas, Alexander; Razeen, Moataz; Dubow, Michael; Gan, Alexander; Chui, Toco Y.; Shah, Nishit; Mehta, Mitul; Gentile, Ronald C.; Weitz, Rishard; Walsh, Joseph B.; Sulai, Yusufu N.; Carroll, Joseph; Dubra, Alfredo; Rosen, Richard B.

2014-01-01

Purpose. To analyze the foveal microvasculature of young healthy eyes and older vasculopathic eyes, imaged using in vivo adaptive optics scanning light ophthalmoscope fluorescein angiography (AOSLO FA). Methods. AOSLO FA imaging of the superficial retinal microvasculature within an 800-μm radius from the foveal center was performed using simultaneous confocal infrared (IR) reflectance (790 nm) and fluorescence (488 nm) channels. Corresponding IR structural and FA perfusion maps were compared with each other to identify nonperfused capillaries adjacent to the foveal avascular zone. Microvascular densities were calculated from skeletonized FA perfusion maps. Results. Sixteen healthy adults (26 eyes; mean age 25 years, range, 21–29) and six patients with a retinal vasculopathy (six eyes; mean age 55 years, range, 44–70) were imaged. At least one nonperfused capillary was observed in five of the 16 healthy nonfellow eyes and in four of the six vasculopathic eyes. Compared with healthy eyes, capillary nonperfusion in the vasculopathic eyes was more extensive. Microvascular density of the 16 healthy nonfellow eyes was 42.0 ± 4.2 mm−1 (range, 33–50 mm−1). All six vasculopathic eyes had decreased microvascular densities. Conclusions. AOSLO FA provides an in vivo method for estimating foveal microvascular density and reveals occult nonperfused retinal capillaries. Nonperfused capillaries in healthy young adults may represent a normal variation and/or an early sign of pathology. Although limited, the normative data presented here is a step toward developing clinically useful microvascular parameters for ocular and/or systemic diseases. PMID:25414179

Early and Later Life Stress Alter Brain Activity and Sleep in Rats

PubMed Central

Mrdalj, Jelena; Pallesen, Ståle; Milde, Anne Marita; Jellestad, Finn Konow; Murison, Robert; Ursin, Reidun; Bjorvatn, Bjørn; Grønli, Janne

2013-01-01

Exposure to early life stress may profoundly influence the developing brain in lasting ways. Neuropsychiatric disorders associated with early life adversity may involve neural changes reflected in EEG power as a measure of brain activity and disturbed sleep. The main aim of the present study was for the first time to characterize possible changes in adult EEG power after postnatal maternal separation in rats. Furthermore, in the same animals, we investigated how EEG power and sleep architecture were affected after exposure to a chronic mild stress protocol. During postnatal day 2–14 male rats were exposed to either long maternal separation (180 min) or brief maternal separation (10 min). Long maternally separated offspring showed a sleep-wake nonspecific reduction in adult EEG power at the frontal EEG derivation compared to the brief maternally separated group. The quality of slow wave sleep differed as the long maternally separated group showed lower delta power in the frontal-frontal EEG and a slower reduction of the sleep pressure. Exposure to chronic mild stress led to a lower EEG power in both groups. Chronic exposure to mild stressors affected sleep differently in the two groups of maternal separation. Long maternally separated offspring showed more total sleep time, more episodes of rapid eye movement sleep and higher percentage of non-rapid eye movement episodes ending in rapid eye movement sleep compared to brief maternal separation. Chronic stress affected similarly other sleep parameters and flattened the sleep homeostasis curves in all offspring. The results confirm that early environmental conditions modulate the brain functioning in a long-lasting way. PMID:23922857

Aggressive posterior retinopathy of prematurity in Asian Indian babies: spectrum of disease and outcome after laser treatment.

PubMed

Sanghi, Gaurav; Dogra, Mangat R; Das, Pranab; Vinekar, Anand; Gupta, Amod; Dutta, Saurabh

2009-10-01

To analyze the spectrum of aggressive posterior retinopathy of prematurity and outcome after laser treatment. This is a retrospective review of 81 eyes of 44 consecutive infants diagnosed to have aggressive posterior retinopathy of prematurity and treated between September 2005 and March 2007 from a large tertiary care center in North India. Qualitative variables were tested for statistical significance using the chi-square test and independent samples with the student's t-test. Mean birth weight and gestational age were 1,259.66 +/- 310.51 g (range, 660-2,000 g) and 29.75 +/- 2.35 weeks (range, 26-36 weeks), respectively. Twenty-one infants (47.72%) had a birth weight > 1,250 g. Thirty-three (40.74%) eyes had Zone 1, and 48 (59.26%) had posterior Zone 2 disease. All eyes underwent confluent laser photocoagulation at a mean postconceptional age of 34.58 +/- 2.19 weeks (range, 31-40.5 weeks). Mean follow-up was 12.8 months (range, 6-24 months). At the last follow-up visit, 55 (71.4%) of 77 eyes had a favorable outcome. Eighteen eyes (23.4%) had a localized (1-3 clock hours) partial peripheral tractional detachment (Stage 4a), which remained stable at last follow-up. Two eyes (2.6%) developed falciform fold involving the macular area, and 2 (2.6%) developed Stage 5 retinopathy of prematurity. Aggressive posterior retinopathy of prematurity is encountered not only in low birth weight infants, but also in heavier and more mature Asian Indian infants. Early, aggressive confluent laser photocoagulation is necessary to maximize outcomes in these eyes.

The effect of transcranial direct current stimulation on contrast sensitivity and visual evoked potential amplitude in adults with amblyopia

PubMed Central

Ding, Zhaofeng; Li, Jinrong; Spiegel, Daniel P.; Chen, Zidong; Chan, Lily; Luo, Guangwei; Yuan, Junpeng; Deng, Daming; Yu, Minbin; Thompson, Benjamin

2016-01-01

Amblyopia is a neurodevelopmental disorder of vision that occurs when the visual cortex receives decorrelated inputs from the two eyes during an early critical period of development. Amblyopic eyes are subject to suppression from the fellow eye, generate weaker visual evoked potentials (VEPs) than fellow eyes and have multiple visual deficits including impairments in visual acuity and contrast sensitivity. Primate models and human psychophysics indicate that stronger suppression is associated with greater deficits in amblyopic eye contrast sensitivity and visual acuity. We tested whether transcranial direct current stimulation (tDCS) of the visual cortex would modulate VEP amplitude and contrast sensitivity in adults with amblyopia. tDCS can transiently alter cortical excitability and may influence suppressive neural interactions. Twenty-one patients with amblyopia and twenty-seven controls completed separate sessions of anodal (a-), cathodal (c-) and sham (s-) visual cortex tDCS. A-tDCS transiently and significantly increased VEP amplitudes for amblyopic, fellow and control eyes and contrast sensitivity for amblyopic and control eyes. C-tDCS decreased VEP amplitude and contrast sensitivity and s-tDCS had no effect. These results suggest that tDCS can modulate visual cortex responses to information from adult amblyopic eyes and provide a foundation for future clinical studies of tDCS in adults with amblyopia. PMID:26763954

The effect of transcranial direct current stimulation on contrast sensitivity and visual evoked potential amplitude in adults with amblyopia.

PubMed

Ding, Zhaofeng; Li, Jinrong; Spiegel, Daniel P; Chen, Zidong; Chan, Lily; Luo, Guangwei; Yuan, Junpeng; Deng, Daming; Yu, Minbin; Thompson, Benjamin

2016-01-14

Amblyopia is a neurodevelopmental disorder of vision that occurs when the visual cortex receives decorrelated inputs from the two eyes during an early critical period of development. Amblyopic eyes are subject to suppression from the fellow eye, generate weaker visual evoked potentials (VEPs) than fellow eyes and have multiple visual deficits including impairments in visual acuity and contrast sensitivity. Primate models and human psychophysics indicate that stronger suppression is associated with greater deficits in amblyopic eye contrast sensitivity and visual acuity. We tested whether transcranial direct current stimulation (tDCS) of the visual cortex would modulate VEP amplitude and contrast sensitivity in adults with amblyopia. tDCS can transiently alter cortical excitability and may influence suppressive neural interactions. Twenty-one patients with amblyopia and twenty-seven controls completed separate sessions of anodal (a-), cathodal (c-) and sham (s-) visual cortex tDCS. A-tDCS transiently and significantly increased VEP amplitudes for amblyopic, fellow and control eyes and contrast sensitivity for amblyopic and control eyes. C-tDCS decreased VEP amplitude and contrast sensitivity and s-tDCS had no effect. These results suggest that tDCS can modulate visual cortex responses to information from adult amblyopic eyes and provide a foundation for future clinical studies of tDCS in adults with amblyopia.

Retinal Wave Patterns Are Governed by Mutual Excitation among Starburst Amacrine Cells and Drive the Refinement and Maintenance of Visual Circuits.

PubMed

Xu, Hong-Ping; Burbridge, Timothy J; Ye, Meijun; Chen, Minggang; Ge, Xinxin; Zhou, Z Jimmy; Crair, Michael C

2016-03-30

Retinal waves are correlated bursts of spontaneous activity whose spatiotemporal patterns are critical for early activity-dependent circuit elaboration and refinement in the mammalian visual system. Three separate developmental wave epochs or stages have been described, but the mechanism(s) of pattern generation of each and their distinct roles in visual circuit development remain incompletely understood. We used neuroanatomical,in vitroandin vivoelectrophysiological, and optical imaging techniques in genetically manipulated mice to examine the mechanisms of wave initiation and propagation and the role of wave patterns in visual circuit development. Through deletion of β2 subunits of nicotinic acetylcholine receptors (β2-nAChRs) selectively from starburst amacrine cells (SACs), we show that mutual excitation among SACs is critical for Stage II (cholinergic) retinal wave propagation, supporting models of wave initiation and pattern generation from within a single retinal cell type. We also demonstrate that β2-nAChRs in SACs, and normal wave patterns, are necessary for eye-specific segregation. Finally, we show that Stage III (glutamatergic) retinal waves are not themselves necessary for normal eye-specific segregation, but elimination of both Stage II and Stage III retinal waves dramatically disrupts eye-specific segregation. This suggests that persistent Stage II retinal waves can adequately compensate for Stage III retinal wave loss during the development and refinement of eye-specific segregation. These experiments confirm key features of the "recurrent network" model for retinal wave propagation and clarify the roles of Stage II and Stage III retinal wave patterns in visual circuit development. Spontaneous activity drives early mammalian circuit development, but the initiation and patterning of activity vary across development and among modalities. Cholinergic "retinal waves" are initiated in starburst amacrine cells and propagate to retinal ganglion cells and higher-order visual areas, but the mechanism responsible for creating their unique and critical activity pattern is incompletely understood. We demonstrate that cholinergic wave patterns are dictated by recurrent connectivity within starburst amacrine cells, and retinal ganglion cells act as "readouts" of patterned activity. We also show that eye-specific segregation occurs normally without glutamatergic waves, but elimination of both cholinergic and glutamatergic waves completely disrupts visual circuit development. These results suggest that each retinal wave pattern during development is optimized for concurrently refining multiple visual circuits. Copyright © 2016 the authors 0270-6474/16/363872-16$15.00/0.

Social Smiling and its Components in High-Risk Infant Siblings Without Later ASD Symptomatology

PubMed Central

Nichols, Caitlin McMahon; Ibañez, Lisa V.; Foss-Feig, Jennifer H.; Stone, Wendy L.

2013-01-01

Impaired affective expression, including social smiling, is common in children with autism spectrum disorder (ASD), and may represent an early marker for ASD in their infant siblings (Sibs-ASD). Social smiling and its component behaviors (eye contact and non-social smiling) were examined at 15 months in Sibs-ASD who demonstrated later ASD symptomatology (Sibs-ASD/AS), those who did not (Sibs-ASD/NS), and low-risk controls (Sibs-TD). Both Sibs-ASD subgroups demonstrated lower levels of social smiling than Sibs-TD, suggesting that early social smiling may reflect elevated genetic vulnerability rather than a specific marker for ASD. Only the Sibs-ASD/AS demonstrated less eye contact and non-social smiling than Sibs-TD, suggesting that different processes, threshold effects, or protective factors may underlie social smiling development in the two Sibs-ASD subgroups. PMID:24057094

Functional Optical Coherence Tomography Enables In Vivo Physiological Assessment of Retinal Rod and Cone Photoreceptors

PubMed Central

Zhang, Qiuxiang; Lu, Rongwen; Wang, Benquan; Messinger, Jeffrey D.; Curcio, Christine A.; Yao, Xincheng

2015-01-01

Transient intrinsic optical signal (IOS) changes have been observed in retinal photoreceptors, suggesting a unique biomarker for eye disease detection. However, clinical deployment of IOS imaging is challenging due to unclear IOS sources and limited signal-to-noise ratios (SNRs). Here, by developing high spatiotemporal resolution optical coherence tomography (OCT) and applying an adaptive algorithm for IOS processing, we were able to record robust IOSs from single-pass measurements. Transient IOSs, which might reflect an early stage of light phototransduction, are consistently observed in the photoreceptor outer segment almost immediately (<4 ms) after retinal stimulation. Comparative studies of dark- and light-adapted retinas have demonstrated the feasibility of functional OCT mapping of rod and cone photoreceptors, promising a new method for early disease detection and improved treatment of diseases such as age-related macular degeneration (AMD) and other eye diseases that can cause photoreceptor damage. PMID:25901915

Automated analysis of connected speech reveals early biomarkers of Parkinson's disease in patients with rapid eye movement sleep behaviour disorder.

PubMed

Hlavnička, Jan; Čmejla, Roman; Tykalová, Tereza; Šonka, Karel; Růžička, Evžen; Rusz, Jan

2017-02-02

For generations, the evaluation of speech abnormalities in neurodegenerative disorders such as Parkinson's disease (PD) has been limited to perceptual tests or user-controlled laboratory analysis based upon rather small samples of human vocalizations. Our study introduces a fully automated method that yields significant features related to respiratory deficits, dysphonia, imprecise articulation and dysrhythmia from acoustic microphone data of natural connected speech for predicting early and distinctive patterns of neurodegeneration. We compared speech recordings of 50 subjects with rapid eye movement sleep behaviour disorder (RBD), 30 newly diagnosed, untreated PD patients and 50 healthy controls, and showed that subliminal parkinsonian speech deficits can be reliably captured even in RBD patients, which are at high risk of developing PD or other synucleinopathies. Thus, automated vocal analysis should soon be able to contribute to screening and diagnostic procedures for prodromal parkinsonian neurodegeneration in natural environments.

Functional Optical Coherence Tomography Enables In Vivo Physiological Assessment of Retinal Rod and Cone Photoreceptors

NASA Astrophysics Data System (ADS)

Zhang, Qiuxiang; Lu, Rongwen; Wang, Benquan; Messinger, Jeffrey D.; Curcio, Christine A.; Yao, Xincheng

2015-04-01

Transient intrinsic optical signal (IOS) changes have been observed in retinal photoreceptors, suggesting a unique biomarker for eye disease detection. However, clinical deployment of IOS imaging is challenging due to unclear IOS sources and limited signal-to-noise ratios (SNRs). Here, by developing high spatiotemporal resolution optical coherence tomography (OCT) and applying an adaptive algorithm for IOS processing, we were able to record robust IOSs from single-pass measurements. Transient IOSs, which might reflect an early stage of light phototransduction, are consistently observed in the photoreceptor outer segment almost immediately (<4 ms) after retinal stimulation. Comparative studies of dark- and light-adapted retinas have demonstrated the feasibility of functional OCT mapping of rod and cone photoreceptors, promising a new method for early disease detection and improved treatment of diseases such as age-related macular degeneration (AMD) and other eye diseases that can cause photoreceptor damage.

Learning One's Place and Position through Play: Social Class and Educational Opportunity in Early Years Education

ERIC Educational Resources Information Center

Stirrup, Julie; Evans, John; Davies, Brian

2017-01-01

Drawing on the theoretical work of the British sociologist Basil Bernstein, this paper documents how learning is structured and organised through play in three Early Years Education (EYE) settings catering for children aged three to five in England, UK. Its data address current issues raised within EYE research relating to "quality and high…

Guideline for Early Interventions

DTIC Science & Technology

2006-04-01

desensitization and reprocessing ( EMDR ) as a early mental health intervention, following mass violence and disasters, is a treatment of choice over other...village. Military operations take place under the eye of the world and are surrounded by high political attention. International missions far exceed...consistently reduce risks of later post-traumatic stress disorder or related adjustment difficulties. • There is no evidence that eye movement

Fixation to features and neural processing of facial expressions in a gender discrimination task

PubMed Central

Neath, Karly N.; Itier, Roxane J.

2017-01-01

Early face encoding, as reflected by the N170 ERP component, is sensitive to fixation to the eyes. Whether this sensitivity varies with facial expressions of emotion and can also be seen on other ERP components such as P1 and EPN, was investigated. Using eye-tracking to manipulate fixation on facial features, we found the N170 to be the only eye-sensitive component and this was true for fearful, happy and neutral faces. A different effect of fixation to features was seen for the earlier P1 that likely reflected general sensitivity to face position. An early effect of emotion (~120 ms) for happy faces was seen at occipital sites and was sustained until ~350 ms post-stimulus. For fearful faces, an early effect was seen around 80 ms followed by a later effect appearing at ~150 ms until ~300 ms at lateral posterior sites. Results suggests that in this emotion-irrelevant gender discrimination task, processing of fearful and happy expressions occurred early and largely independently of the eye-sensitivity indexed by the N170. Processing of the two emotions involved different underlying brain networks active at different times. PMID:26277653

Early sensitivity for eyes within faces: a new neuronal account of holistic and featural processing

PubMed Central

Nemrodov, Dan; Anderson, Thomas; Preston, Frank F.; Itier, Roxane J.

2017-01-01

Eyes are central to face processing however their role in early face encoding as reflected by the N170 ERP component is unclear. Using eye tracking to enforce fixation on specific facial features, we found that the N170 was larger for fixation on the eyes compared to fixation on the forehead, nasion, nose or mouth, which all yielded similar amplitudes. This eye sensitivity was seen in both upright and inverted faces and was lost in eyeless faces, demonstrating it was due to the presence of eyes at fovea. Upright eyeless faces elicited largest N170 at nose fixation. Importantly, the N170 face inversion effect (FIE) was strongly attenuated in eyeless faces when fixation was on the eyes but was less attenuated for nose fixation and was normal when fixation was on the mouth. These results suggest the impact of eye removal on the N170 FIE is a function of the angular distance between the fixated feature and the eye location. We propose the Lateral Inhibition, Face Template and Eye Detector based (LIFTED) model which accounts for all the present N170 results including the FIE and its interaction with eye removal. Although eyes elicit the largest N170 response, reflecting the activity of an eye detector, the processing of upright faces is holistic and entails an inhibitory mechanism from neurons coding parafoveal information onto neurons coding foveal information. The LIFTED model provides a neuronal account of holistic and featural processing involved in upright and inverted faces and offers precise predictions for further testing. PMID:24768932

Eye morphogenesis driven by epithelial flow into the optic cup facilitated by modulation of bone morphogenetic protein

PubMed Central

Heermann, Stephan; Schütz, Lucas; Lemke, Steffen; Krieglstein, Kerstin; Wittbrodt, Joachim

2015-01-01

The hemispheric, bi-layered optic cup forms from an oval optic vesicle during early vertebrate eye development through major morphological transformations. The overall basal surface, facing the developing lens, is increasing, while, at the same time, the space basally occupied by individual cells is decreasing. This cannot be explained by the classical view of eye development. Using zebrafish (Danio rerio) as a model, we show that the lens-averted epithelium functions as a reservoir that contributes to the growing neuroretina through epithelial flow around the distal rims of the optic cup. We propose that this flow couples morphogenesis and retinal determination. Our 4D data indicate that future stem cells flow from their origin in the lens-averted domain of the optic vesicle to their destination in the ciliary marginal zone. BMP-mediated inhibition of the flow results in ectopic neuroretina in the RPE domain. Ultimately the ventral fissure fails to close resulting in coloboma. DOI: http://dx.doi.org/10.7554/eLife.05216.001 PMID:25719386

Development and learning of saccadic eye movements in 7- to 42-month-old children.

PubMed

Alahyane, Nadia; Lemoine-Lardennois, Christelle; Tailhefer, Coline; Collins, Thérèse; Fagard, Jacqueline; Doré-Mazars, Karine

2016-01-01

From birth, infants move their eyes to explore their environment, interact with it, and progressively develop a multitude of motor and cognitive abilities. The characteristics and development of oculomotor control in early childhood remain poorly understood today. Here, we examined reaction time and amplitude of saccadic eye movements in 93 7- to 42-month-old children while they oriented toward visual animated cartoon characters appearing at unpredictable locations on a computer screen over 140 trials. Results revealed that saccade performance is immature in children compared to a group of adults: Saccade reaction times were longer, and saccade amplitude relative to target location (10° eccentricity) was shorter. Results also indicated that performance is flexible in children. Although saccade reaction time decreased as age increased, suggesting developmental improvements in saccade control, saccade amplitude gradually improved over trials. Moreover, similar to adults, children were able to modify saccade amplitude based on the visual error made in the previous trial. This second set of results suggests that short visual experience and/or rapid sensorimotor learning are functional in children and can also affect saccade performance.

Differential expression of endothelial nutrient transporters (MCT1 and GLUT1) in the developing eyes of mice.

PubMed

Kishimoto, Ayuko; Takahashi-Iwanaga, Hiromi; Watanabe M, Masahiko; Iwanaga, Toshihiko

2016-12-01

The blood-brain barrier in the neonatal brain expresses the monocarboxylate transporter (MCT)-1 rather than the glucose transporter (GLUT)-1, due to the special energy supply during the suckling period. The hyaloid vascular system, consisting of the vasa hyaloidea propria and tunica vasculosa lentis, is a temporary vasculature present only during the early development of mammalian eyes and later regresses. Although the ocular vasculature manifests such a unique developmental process, no information is available concerning the expression of endothelial nutrient transporters in the developing eye. The present immunohistochemical study using whole mount preparations of murine eyes found that the hyaloid vascular system predominantly expressed GLUT1 in the endothelium, in contrast to the brain endothelium. Characteristically, the endothelium in peripheral regions of the neonatal hyaloid vessels displayed a mosaic pattern of MCT1-immunoreactive cells scattered within the GLUT1-expressing endothelium. The proper retinal vessels first developed by sprouting angiogenesis endowed with filopodia, which were absolutely free from the immunoreactivities of GLUT1 and MCT1. The remodeling retinal capillary networks and veins in the surface layer of the retina mainly expressed MCT1 until the weaning period. Immunostaining of MCT1 in the retina revealed fine radicular processes projecting from the endothelium, differing from the MCT1-immunonegative filopodia. These findings suggest that the expression of nutrient transporters in the ocular blood vessels is differentially regulated at a cellular level and that the neonatal eyes provide an interesting model for research on nutrient transporters in the endothelium. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

Mouw, Kent W.; Department of Radiation Oncology, Massachusetts General Hospital, Boston, Massachusetts; Sethi, Roshan V.

Purpose: To investigate long-term disease and toxicity outcomes for pediatric retinoblastoma patients treated with proton radiation therapy (PRT). Methods and Materials: This is a retrospective analysis of 49 retinoblastoma patients (60 eyes) treated with PRT between 1986 and 2012. Results: The majority (84%) of patients had bilateral disease, and nearly half (45%) had received prior chemotherapy. At a median follow-up of 8 years (range, 1-24 years), no patients died of retinoblastoma or developed metastatic disease. The post-PRT enucleation rate was low (18%), especially in patients with early-stage disease (11% for patients with International Classification for Intraocular Retinoblastoma [ICIR] stage A-B disease vs 23%more » for patients with ICIR stage C-D disease). Post-PRT ophthalmologic follow-up was available for 61% of the preserved eyes (30 of 49): 14 of 30 eyes (47%) had 20/40 visual acuity or better, 7 of 30 (23%) had moderate visual acuity (20/40-20/600), and 9 of 30 (30%) had little or no useful vision (worse than 20/600). Twelve of 60 treated eyes (20%) experienced a post-PRT event requiring intervention, with cataracts the most common (4 eyes). No patients developed an in-field second malignancy. Conclusions: Long-term follow-up of retinoblastoma patients treated with PRT demonstrates that PRT can achieve high local control rates, even in advanced cases, and many patients retain useful vision in the treated eye. Treatment-related ocular side effects were uncommon, and no radiation-associated malignancies were observed.« less

IRIS COLOUR CLASSIFICATION SCALES – THEN AND NOW

PubMed Central

Grigore, Mariana; Avram, Alina

2015-01-01

Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual’s eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale. PMID:27373112

IRIS COLOUR CLASSIFICATION SCALES--THEN AND NOW.

PubMed

Grigore, Mariana; Avram, Alina

2015-01-01

Eye colour is one of the most obvious phenotypic traits of an individual. Since the first documented classification scale developed in 1843, there have been numerous attempts to classify the iris colour. In the past centuries, iris colour classification scales has had various colour categories and mostly relied on comparison of an individual's eye with painted glass eyes. Once photography techniques were refined, standard iris photographs replaced painted eyes, but this did not solve the problem of painted/ printed colour variability in time. Early clinical scales were easy to use, but lacked objectivity and were not standardised or statistically tested for reproducibility. The era of automated iris colour classification systems came with the technological development. Spectrophotometry, digital analysis of high-resolution iris images, hyper spectral analysis of the human real iris and the dedicated iris colour analysis software, all accomplished an objective, accurate iris colour classification, but are quite expensive and limited in use to research environment. Iris colour classification systems evolved continuously due to their use in a wide range of studies, especially in the fields of anthropology, epidemiology and genetics. Despite the wide range of the existing scales, up until present there has been no generally accepted iris colour classification scale.

Early evolution of multifocal optics for well-focused colour vision in vertebrates.

PubMed

Gustafsson, O S E; Collin, S P; Kröger, R H H

2008-05-01

Jawless fishes (Agnatha; lampreys and hagfishes) most closely resemble the earliest stage in vertebrate evolution and lamprey-like animals already existed in the Lower Cambrian [about 540 million years ago (MYA)]. Agnathans are thought to have separated from the main vertebrate lineage at least 500 MYA. Hagfishes have primitive eyes, but the eyes of adult lampreys are well-developed. The southern hemisphere lamprey, Geotria australis, possesses five types of opsin genes, three of which are clearly orthologous to the opsin genes of jawed vertebrates. This suggests that the last common ancestor of all vertebrate lineages possessed a complex colour vision system. In the eyes of many bony fishes and tetrapods, well-focused colour images are created by multifocal crystalline lenses that compensate for longitudinal chromatic aberration. To trace the evolutionary origins of multifocal lenses, we studied the optical properties of the lenses in four species of lamprey (Geotria australis, Mordacia praecox, Lampetra fluviatilis and Petromyzon marinus), with representatives from all three of the extant lamprey families. Multifocal lenses are present in all lampreys studied. This suggests that the ability to create well-focused colour images with multifocal optical systems also evolved very early.

Early lens ablation causes dramatic long-term effects on the shape of bones in the craniofacial skeleton of Astyanax mexicanus.

PubMed

Dufton, Megan; Hall, Brian K; Franz-Odendaal, Tamara A

2012-01-01

The Mexican tetra, Astyanax mexicanus, exists as two morphs of a single species, a sighted surface morph and a blind cavefish. In addition to eye regression, cavefish have an increased number of taste buds, maxillary teeth and have an altered craniofacial skeleton compared to the sighted morph. We investigated the effect the lens has on the development of the surrounding skeleton, by ablating the lens at different time points during ontogeny. This unique long-term study sheds light on how early embryonic manipulations on the eye can affect the shape of the adult skull more than a year later, and the developmental window during which time these effects occur. The effects of lens ablation were analyzed by whole-mount bone staining, immunohistochemisty and landmark based morphometric analyzes. Our results indicate that lens ablation has the greatest impact on the skeleton when it is ablated at one day post fertilisation (dpf) compared to at four dpf. Morphometric analyzes indicate that there is a statistically significant difference in the shape of the supraorbital bone and suborbital bones four through six. These bones expand into the eye orbit exhibiting plasticity in their shape. Interestingly, the number of caudal teeth on the lower jaw is also affected by lens ablation. In contrast, the shape of the calvariae, the length of the mandible, and the number of mandibular taste buds are unaltered by lens removal. We demonstrate the plasticity of some craniofacial elements and the stability of others in the skull. Furthermore, this study highlights interactions present between sensory systems during early development and sheds light on the cavefish phenotype.

Electrophoresis of tear proteins as a new diagnostic tool for two high risk groups for dry eye: computer users and contact lens wearers.

PubMed

Chiva, Andreea

2011-08-15

Dry eye is the most prevalent condition seen by the ophthalmologist, in particular in elderly. The identification of new common risk factors (computer use and contact lens wear) extends the disease among the young people. The early diagnosis of dry eye is essential, but difficult, because the biochemical changes in tear film usually occur before any detectable signs. Due its advantages, electrophoresis of tear proteins could be an important tool for diagnosis of tear film impairment in high risk groups for dry eye. The role of tear proteins electrophoresis in early diagnosis of dry eye related to computer use and contact lens wear, as well as the biochemical changes in these high risk groups are presented. This review will summarize the actual data concerning the electrophoretic changes of tear proteins in computer users and contact lens wearers, two common high risk groups for dry eye. Electrophoresis of tear proteins using automated system Hyrys-Hydrasys SEBIA France is an important tool for early diagnosis of tear film alterations and monitoring of therapy. The quantification of many proteins in a single analysis using a small quantity of unconcentrated reflex tears is the main advantage of this technique. Electrophoresis of tear proteins should became a prerequisite, in particular for computer users less than 3 h/day, as well as at prescribing contact lenses.

Development of online use of theory of mind during adolescence: An eye-tracking study.

PubMed

Symeonidou, Irene; Dumontheil, Iroise; Chow, Wing-Yee; Breheny, Richard

2016-09-01

We investigated the development of theory of mind use through eye-tracking in children (9-13years old, n=14), adolescents (14-17.9years old, n=28), and adults (19-29years old, n=23). Participants performed a computerized task in which a director instructed them to move objects placed on a set of shelves. Some of the objects were blocked off from the director's point of view; therefore, participants needed to take into consideration the director's ignorance of these objects when following the director's instructions. In a control condition, participants performed the same task in the absence of the director and were told that the instructions would refer only to items in slots without a back panel, controlling for general cognitive demands of the task. Participants also performed two inhibitory control tasks. We replicated previous findings, namely that in the director-present condition, but not in the control condition, children and adolescents made more errors than adults, suggesting that theory of mind use improves between adolescence and adulthood. Inhibitory control partly accounted for errors on the director task, indicating that it is a factor of developmental change in perspective taking. Eye-tracking data revealed early eye gaze differences between trials where the director's perspective was taken into account and those where it was not. Once differences in accuracy rates were considered, all age groups engaged in the same kind of online processing during perspective taking but differed in how often they engaged in perspective taking. When perspective is correctly taken, all age groups' gaze data point to an early influence of perspective information. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Involvement of Lypge in the formation of eye and pineal gland in zebrafish.

PubMed

Ji, Dongrui; Wang, Su; Li, Mingyue; Zhang, Shicui; Li, Hongyan

2018-02-05

The proteins of Ly-6 (lymphocyte antigen-6) family are involved in the regulation of immunoreaction, cell migration and adhesion, and neuronal excitability. However, little is known about the function of Ly-6 proteins in embryogenesis. Herein, we identified a GPI anchored Ly-6 member named ly6 expressed in pineal gland and eye (lypge). Dynamic expression pattern of lypge was revealed by whole mount in situ hybridization. It was strikingly expressed in the pineal gland and cone photoreceptor, and its expression was regulated by orthodenticle homolog 5 (otx5) which has been shown to control the expression of many pineal genes. In addition, we demonstrated that lypge was rhythmically expressed in larvae from 4dpf on. Moreover, knockdown of lypge resulted in small head and small eye formed in zebrafish embryos. These suggest that Lypge is involved in the formation of the eye and pineal gland in early development of zebrafish. Copyright © 2017 Elsevier B.V. All rights reserved.

Fetal eye movements on magnetic resonance imaging.

PubMed

Woitek, Ramona; Kasprian, Gregor; Lindner, Christian; Stuhr, Fritz; Weber, Michael; Schöpf, Veronika; Brugger, Peter C; Asenbaum, Ulrika; Furtner, Julia; Bettelheim, Dieter; Seidl, Rainer; Prayer, Daniela

2013-01-01

Eye movements are the physical expression of upper fetal brainstem function. Our aim was to identify and differentiate specific types of fetal eye movement patterns using dynamic MRI sequences. Their occurrence as well as the presence of conjugated eyeball motion and consistently parallel eyeball position was systematically analyzed. Dynamic SSFP sequences were acquired in 72 singleton fetuses (17-40 GW, three age groups [17-23 GW, 24-32 GW, 33-40 GW]). Fetal eye movements were evaluated according to a modified classification originally published by Birnholz (1981): Type 0: no eye movements; Type I: single transient deviations; Type Ia: fast deviation, slower reposition; Type Ib: fast deviation, fast reposition; Type II: single prolonged eye movements; Type III: complex sequences; and Type IV: nystagmoid. In 95.8% of fetuses, the evaluation of eye movements was possible using MRI, with a mean acquisition time of 70 seconds. Due to head motion, 4.2% of the fetuses and 20.1% of all dynamic SSFP sequences were excluded. Eye movements were observed in 45 fetuses (65.2%). Significant differences between the age groups were found for Type I (p = 0.03), Type Ia (p = 0.031), and Type IV eye movements (p = 0.033). Consistently parallel bulbs were found in 27.3-45%. In human fetuses, different eye movement patterns can be identified and described by MRI in utero. In addition to the originally classified eye movement patterns, a novel subtype has been observed, which apparently characterizes an important step in fetal brainstem development. We evaluated, for the first time, eyeball position in fetuses. Ultimately, the assessment of fetal eye movements by MRI yields the potential to identify early signs of brainstem dysfunction, as encountered in brain malformations such as Chiari II or molar tooth malformations.

Shape Up: An Eye-Tracking Study of Preschoolers' Shape Name Processing and Spatial Development

ERIC Educational Resources Information Center

Verdine, Brian N.; Bunger, Ann; Athanasopoulou, Angeliki; Golinkoff, Roberta Michnick; Hirsh-Pasek, Kathy

2017-01-01

Learning the names of geometric shapes is at the intersection of early spatial, mathematical, and language skills, all important for school-readiness and predictors of later abilities in science, technology, engineering, and mathematics (STEM). We investigated whether socioeconomic status (SES) influenced children's processing of shape names and…

The Cortically Blind Infant: Educational Guidelines and Suggestions.

ERIC Educational Resources Information Center

Silverrain, Ann

Cortical blindness is defined and its diagnosis is explained. Guidelines and sample activities are presented for use in a cognitive/visual/multi-sensory stimulation program to produce progress in cortically blind infants. The importance of using the eyes from birth through early development in order to form the nerve pathways responsible for…

Biracial and Monoracial Infant Own-Race Face Perception: An Eye Tracking Study

ERIC Educational Resources Information Center

Gaither, Sarah E.; Pauker, Kristin; Johnson, Scott P.

2012-01-01

We know that early experience plays a crucial role in the development of face processing, but we know little about how infants learn to distinguish faces from different races, especially for non-Caucasian populations. Moreover, it is unknown whether differential processing of different race faces observed in typically studied monoracial infants…

Pathfinding in a large vertebrate axon tract: isotypic interactions guide retinotectal axons at multiple choice points

PubMed Central

Pittman, Andrew J.; Law, Mei-Yee; Chien, Chi-Bin

2008-01-01

Summary Navigating axons respond to environmental guidance signals, but can also follow axons that have gone before—pioneer axons. Pioneers have been studied extensively in simple systems, but the role of axon-axon interactions remains largely unexplored in large vertebrate axon tracts, where cohorts of identical axons could potentially use isotypic interactions to guide each other through multiple choice points. Furthermore, the relative importance of axon-axon interactions compared to axon-autonomous receptor function has not been assessed. Here we test the role of axon-axon interactions in retinotectal development, by devising a technique to selectively remove or replace early-born retinal ganglion cells (RGCs). We find that early RGCs are both necessary and sufficient for later axons to exit the eye. Furthermore, introducing misrouted axons by transplantation reveals that guidance from eye to tectum relies heavily on interactions between axons, including both pioneer-follower and community effects. We conclude that axon-axon interactions and ligand-receptor signaling have coequal roles, cooperating to ensure the fidelity of axon guidance in developing vertebrate tracts. PMID:18653554

Regression of early diabetic macular oedema is associated with prevention of dark adaptation

PubMed Central

Arden, G B; Jyothi, S; Hogg, C H; Lee, Y F; Sivaprasad, S

2011-01-01

Hypothesis Dark-adapted rods consume oxygen at high rates and light adaptation decreases this oxygen burden and can have therapeutic effects on diabetic macular oedema (DMO). Methods Patients with mild non-proliferative diabetic retinopathy (DR) and early, untreated non-sight-threatening DMO slept for 6 months wearing masks that illuminated the eyelid of one closed eye by 505 nm light. Exclusion criteria were any concomitant eye disease, DR >ETDRS grade 35, and other systemic diseases. Primary outcome: change of OCT retinal thickness in the local region where oedema was present. Results A total of 34 out of 40 patients completed the study. Mean baseline OCT macular cube thickness was equivalent for study and fellow eyes. But study eyes had a greater mean thickness in the central subfield zone 1 (282±53 μm) vs (256±19 μm) the fellow eyes. Twenty-eight study eyes showed intraretinal cysts compared with nine in the fellow eyes. At 6 months, only 19 study eyes had cysts while cysts were seen in 20 fellow eyes. After 6 months, the worst affected ETDRS zone and the central subfield zone 1 reduced in thickness in study eyes only by 12 μm (95% CI 20 to −7, P=0.01). The secondary outcomes of change in visual acuity, achromatic contrast sensitivity, and microperimetric thresholds improved significantly in study eyes and deteriorated in fellow eyes. Conclusions Sleeping in dim light that can keep rods light adapted may reverse the changes of DMO. PMID:22020171

Callous-unemotional traits in children and mechanisms of impaired eye contact during expressions of love: a treatment target?

PubMed

Dadds, Mark R; Allen, Jennifer L; McGregor, Kimberley; Woolgar, Matthew; Viding, Essi; Scott, Stephen

2014-07-01

We previously hypothesised that the early development of psychopathy is associated with a failure to attend to the eyes of attachment figures, and we have presented preliminary data from a parent-child 'love' scenario in support of this. Here, we confirm the association in a larger sample and test mechanisms of impaired eye contact during expressions of love in control and behaviourally disturbed children. Oppositional defiant disorder children, assessed for callous-unemotional (CU) traits, and controls, were observed in a brief interaction task where the mother was asked to show love to her child. Eye contact and affection were measured for each dyad. As predicted, there were no group differences in affection and eye contact expressed by mothers; levels of CU traits predicted low levels of eye contact towards their mothers across all groups of children. As expected, low eye contact was correlated with psychopathic fearlessness in their fathers, and maternal reports of negative feelings towards the child. Independent observations showed that child's behaviour largely drives the low eye contact associated with CU traits, and low eye contact was not associated with independent observations of the quality of attachment-related behaviours in mothers. Impaired eye contact is a unique characteristic of children with CU traits; these impairments are largely independent of maternal behaviour, but associated with psychopathic traits in the fathers. These impairments should be tested for functional significance and amenability to change in longitudinal and treatment studies. © 2013 The Authors. Journal of Child Psychology and Psychiatry © 2013 Association for Child and Adolescent Mental Health.

Early alcohol exposure impairs ocular dominance plasticity throughout the critical period.

PubMed

Medina, Alexandre E; Ramoa, Ary S

2005-06-09

Animal models of fetal alcohol syndrome (FAS) have revealed an impairment of sensory neocortex plasticity. Here, we examine whether early alcohol exposure leads to a permanent impairment of ocular dominance plasticity (OD) or to an alteration in the timing of the critical period. Ferrets were exposed to alcohol during a brief period of development prior to eye opening and effects of monocular deprivation examined during early, mid and late critical period. Single-unit electrophysiology revealed markedly reduced OD plasticity at every age examined. This finding provides evidence that early alcohol exposure does not affect the timing or duration of the critical period of OD plasticity and suggests an enduring impairment of neural plasticity in FAS.

Early light deprivation effects on human cone-driven retinal function.

PubMed

Esposito Veneruso, Paolo; Ziccardi, Lucia; Magli, Giulia; Parisi, Vincenzo; Falsini, Benedetto; Magli, Adriano

2017-03-01

To assess whether the early light deprivation induced by congenital cataract may influence the cone-driven retinal function in humans. Forty-one patients affected by congenital cataract (CC) who had undergone uncomplicated cataract extraction surgery and intraocular lens implant, and 14 healthy subjects (HS) were enrolled. All patients underwent complete ophthalmological and orthoptic evaluations and best-corrected visual acuity (BCVA) measurement; light-adapted full-field electroretinograms (ERG) and photopic negative responses (PhNR) were recorded to obtain a reliable measurement of the outer/inner retinal function and of the retinal ganglion cells' function respectively. Mean values of light-adapted ERG a- and b-wave and PhNR amplitude of CC eyes were significantly reduced and photopic ERG b-wave implicit time mean values were significantly delayed when compared to HS ones. When studying photopic ERG mean amplitudes at 5 ms, significant differences were found when comparing CC and control eyes. In CC eyes, statistically significant correlations were found between a- and b- wave amplitudes and PhNR amplitudes. No significant correlations were found between ERG parameters and BCVA, as well as between the age of CC patients at surgery and the time elapsed from lens extraction. No significant differences were found when functional parameters of bilateral and unilateral congenital cataract (uCC) eyes were compared, however uCC eyes showed significant differences when compared with contralateral healthy eyes. We found a significant impairment of cone-driven retinal responses in patients with a history of congenital cataract. These changes might result from the long-lasting effects of early light deprivation on the cone retinal pathways. Our findings support the relevance of retinal involvement in deficits induced by early light deprivation. © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

[Core principles of treatment of corneal damage in patients with thyroid eye disease].

PubMed

Grusha, Y O; Ismailova, D S; Sherstneva, L V

To develop a therapeutic approach and to estimate the efficiency of complex treatment of corneal damage in patients with thyroid eye disease (TED). The study enrolled 44 patients (52 eyes) divided into 2 groups depending on the severity of corneal damage. Treatment of those with severe involvement included pathogenetic measures (pulse steroid therapy and/or radiation therapy) and surgery (orbital decompression, eyelid and corneal surgery). As the result of the treatment, orbital inflammation decreased and the state of the cornea improved in all patients. The treatment of corneal damage in patients with TED may differ depending on numerous factors, such as the severity of corneal damage and activity of orbital inflammation. Taking into account the potential danger of corneal involvement, one should make efforts to early detection and management of the risk factors.

Central corneal thickness measurements in unoperated eyes and eyes after PRK for myopia using Pentacam, Orbscan II, and ultrasonic pachymetry.

PubMed

Kim, Sun Woong; Byun, Yeo Jue; Kim, Eung Kweon; Kim, Tae-im

2007-11-01

To compare central corneal thickness measurements obtained in unoperated eyes and eyes after myopic photorefractive keratectomy (PRK) using a rotating Scheimpflug camera (Pentacam), a scanning slit corneal topography system (Orbscan II), and ultrasonic pachymetry. Corneal thickness was measured using Pentacam, Orbscan II, and ultrasonic pachymetry in 25 unoperated eyes (unoperated group), 24 eyes 1 to 3 months after myopic PRK (early postoperative PRK group), and 21 eyes 4 months or more after myopic PRK (late postoperative PRK group). In the unoperated group, corneal thickness measurements were similar for all three methods (P=.125). In the early postoperative PRK group, Orbscan measurements were thinner than Pentacam and ultrasonic measurements by a mean of 69.4 microm and 63.4 microm (P<.001 and P=.002, respectively). In the late postoperative PRK group, Orbscan measurements were thinner than Pentacam measurements by a mean of 36.0 microm (P=.017). Pentacam and ultrasonic pachymetry measurements were similar for all three groups with a mean difference of approximately 10 microm. Following myopic PRK, Pentacam was comparable to ultrasonic pachymetry in measuring corneal thickness, whereas Orbscan measurements were thinner.

Rapid eye movement sleep does not seem to unbind memories from their emotional context.

PubMed

Deliens, Gaétane; Neu, Daniel; Peigneux, Philippe

2013-12-01

Sleep unbinds memories from their emotional learning context, protecting them from emotional interference due to a change of mood between learning and recall. According to the 'sleep to forget and sleep to remember' model, emotional unbinding takes place during rapid eye movement sleep. To test this hypothesis, we investigated emotional contextual interference effects after early versus late post-learning sleep periods, in which slow wave and rapid eye movement sleep, respectively, predominate. Participants learned a list of neutral word pairs after induction of a happy or a sad mood, then slept immediately afterwards for 3 h of early or late sleep under polysomnographic recording, in a within-subject counterbalanced design. They slept for 3 h before learning in the late sleep condition. Polysomnographic data confirmed more rapid eye movement sleep in the late than in the early sleep condition. After awakening, half the list was recalled after induction of a similar mood than during the encoding session (non-interference condition), and the other half of the list was recalled after induction of a different mood (interference condition). The results disclosed an emotional interference effect on recall both in the early and late sleep conditions, which does not corroborate the hypothesis of a rapid eye movement sleep-related protection of recent memories from emotional contextual interference. Alternatively, the contextual demodulation process initiated during the first post-learning night might need several consecutive nights of sleep to be achieved. © 2013 European Sleep Research Society.

Interferon gamma-inducible protein-10 (IP-10) and eotaxin as biomarkers in age-related macular degeneration.

PubMed

Mo, Fong Ming; Proia, Alan D; Johnson, Walter H; Cyr, Desiree; Lashkari, Kameran

2010-08-01

To analyze serum cytokine levels in subjects with different stages of AMD and to study the expression of salient cytokines in postmortem eyes with AMD. A suspension array system was used to analyze sera (n = 18 to 20/group) from control subjects and those with early AMD (AREDS stage 1), intermediate dry AMD (AREDS stage 3), advanced AMD with geographic atrophy (GA), or neovascular AMD (CNV). Postmortem eyes with AMD or control eyes were examined immunohistochemically for expression of IP-10 and eotaxin (n = 4 to 8/group). Serum eotaxin and IP-10 levels were significantly elevated in all stages of AMD, except for eotaxin levels in neovascular AMD (P < 0.07). The peak of serum IP-10 concentration was at intermediate dry AMD. In donor eyes, IP-10 and eotaxin expressions were increased in the RPE of eyes with early AMD, GA, and CNV. Eotaxin accumulated within the layer of basal linear/laminar deposits in all stages of AMD, while IP-10 was mainly in eyes with GA and CNV. IP-10 was abundant in the connective tissue matrix associated with CNV, and eotaxin was usually present but more focally and with less intense staining. Both IP-10 and eotaxin were expressed by neovascular endothelial cells. Both IP-10 and eotaxin were expressed in the neurosensory retina, but there was no detectable difference in staining between eyes with or without AMD. IP-10 and eotaxin may be early biomarkers in AMD. The authors hypothesize that the relative balance between levels of IP-10 and eotaxin is critical in regulating the neovascular response.

Remodeling of the Connective Tissue Microarchitecture of the Lamina Cribrosa in Early Experimental Glaucoma

PubMed Central

Roberts, Michael D.; Grau, Vicente; Grimm, Jonathan; Reynaud, Juan; Bellezza, Anthony J.; Burgoyne, Claude F.; Downs, J. Crawford

2009-01-01

Purpose To characterize the trabeculated connective tissue microarchitecture of the lamina cribrosa (LC) in terms of total connective tissue volume (CTV), connective tissue volume fraction (CTVF), predominant beam orientation, and material anisotropy in monkeys with early experimental glaucoma (EG). Methods The optic nerve heads from three monkeys with unilateral EG and four bilaterally normal monkeys were three dimensionally reconstructed from tissues perfusion fixed at an intraocular pressure of 10 mm Hg. A three-dimensional segmentation algorithm was used to extract a binary, voxel-based representation of the porous LC connective tissue microstructure that was regionalized into 45 subvolumes, and the following quantities were calculated: total CTV within the LC, mean and regional CTVF, regional predominant beam orientation, and mean and regional material anisotropy. Results Regional variation within the laminar microstructure was considerable within the normal eyes of all monkeys. The laminar connective tissue was generally most dense in the central and superior regions for the paired normal eyes, and laminar beams were radially oriented at the periphery for all eyes considered. CTV increased substantially in EG eyes compared with contralateral normal eyes (82%, 44%, 45% increases; P < 0.05), but average CTVF changed little (−7%, 1%, and −2% in the EG eyes). There were more laminar beams through the thickness of the LC in the EG eyes than in the normal controls (46%, 18%, 17% increases). Conclusions The substantial increase in laminar CTV with little change in CTVF suggests that significant alterations in connective and nonconnective tissue components in the laminar region occur in the early stages of glaucomatous damage. PMID:18806292

Choroidal metastasis from early rectal cancer: Case report and literature review

PubMed Central

Tei, Mitsuyoshi; Wakasugi, Masaki; Akamatsu, Hiroki

2014-01-01

INTRODUCTION Choroidal metastasis from colorectal cancer is rare, and there have been no reported cases of such metastasis from early colorectal cancer. We report a case of choroidal metastasis from early rectal cancer. PRESENTATION OF CASE A 61 year-old-man experienced myodesopsia in the left eye 2 years and 6 months after primary rectal surgery for early cancer, and was diagnosed with left choroidal metastasis and multiple lung metastases. Radiotherapy was initiated for the left eye and systemic chemotherapy is initiated for the multiple lung metastases. The patient is living 2 years and 3 months after the diagnosis of choroidal metastasis without signs of recurrence in the left eye, and continues to receive systemic chemotherapy for multiple lung metastases. DISCUSSION Current literatures have few recommendations regarding the appropriate treatment of choroidal metastasis from colorectal cancer, but an aggressive multi-disciplinary approach may be effective in local regression. CONCLUSION This is the first report of choroidal metastasis from early rectal cancer. We consider it important to enforce systemic chemotherapy in addition to radiotherapy for choroidal metastasis from colorectal cancer. PMID:25460493

Choroidal metastasis from early rectal cancer: Case report and literature review.

PubMed

Tei, Mitsuyoshi; Wakasugi, Masaki; Akamatsu, Hiroki

2014-01-01

Choroidal metastasis from colorectal cancer is rare, and there have been no reported cases of such metastasis from early colorectal cancer. We report a case of choroidal metastasis from early rectal cancer. A 61 year-old-man experienced myodesopsia in the left eye 2 years and 6 months after primary rectal surgery for early cancer, and was diagnosed with left choroidal metastasis and multiple lung metastases. Radiotherapy was initiated for the left eye and systemic chemotherapy is initiated for the multiple lung metastases. The patient is living 2 years and 3 months after the diagnosis of choroidal metastasis without signs of recurrence in the left eye, and continues to receive systemic chemotherapy for multiple lung metastases. Current literatures have few recommendations regarding the appropriate treatment of choroidal metastasis from colorectal cancer, but an aggressive multi-disciplinary approach may be effective in local regression. This is the first report of choroidal metastasis from early rectal cancer. We consider it important to enforce systemic chemotherapy in addition to radiotherapy for choroidal metastasis from colorectal cancer. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Longitudinal Increase in Anisometropia in Older Adults

PubMed Central

Haegerstrom-Portnoy, Gunilla; Schneck, Marilyn E.; Lott, Lori A.; Hewlett, Susan E.; Brabyn, John A.

2014-01-01

Purpose Anisometropia shows an exponential increase in prevalence with increasing age based on cross-sectional studies. The purpose of this study was to evaluate longitudinal changes in anisometropia in all refractive components in older observers and to assess the influence of early cataract development. Methods Refractive error was assessed at two time points separated by ~12 years in 118 older observers (ages 67.1 and 79.3 years at the two test times). Anisometropia defined as ≥1.00 D was calculated for all refractive components. The subjects had intact ocular lenses in both eyes throughout the study. Lens evaluations were performed at the second test using LOCS III. Results All refractive components approximately doubled in prevalence of anisometropia. Spherical equivalent anisometropia changed from 16.1% to 32.2%. Similar changes were found for spherical error (17% to 38.1%), primary astigmatism (7.6% to 17.8%) and oblique astigmatism (14.4% to 29.7%). Many who did not have anisometropia at the first visit subsequently developed anisometropia (for ex. 26.3% for spherical error and 22.9% for oblique cylinder). The onset of anisometropia occurred at all ages within the studied age range with no particular preference for any one age. A small number lost anisometropia over time. Individual comparisons of refractive error changes in the two eyes in combination with nuclear lens changes showed that early changes in nuclear sclerosis in the two eyes could account for a large proportion of anisometropia (~40%) but unequal hyperopic shift in the spherical component in the two eyes was the primary cause of the anisometropia. Conclusions Anisometropia is at least 10 times more common in the elderly than in children and anisometropia develops in all refractive components in the oldest observers. Clinicians need to be aware of this common condition that could lead to binocular vision problems and potentially cause falls in the elderly. PMID:24276578

Awareness, Knowledge, and Concern about Age-Related Macular Degeneration

ERIC Educational Resources Information Center

Cimarolli, Verena R.; Laban-Baker, Allie; Hamilton, Wanda S.; Stuen, Cynthia

2012-01-01

Age-related macular degeneration (AMD)--a common eye disease causing vision loss--can be detected early through regular eye-health examinations, and measures can be taken to prevent visual decline. Getting eye examinations requires certain levels of awareness, knowledge, and concern related to AMD. However, little is known about AMD-related…

Intact unconscious processing of eye contact in schizophrenia.

PubMed

Seymour, Kiley; Rhodes, Gillian; Stein, Timo; Langdon, Robyn

2016-03-01

The perception of eye gaze is crucial for social interaction, providing essential information about another person's goals, intentions, and focus of attention. People with schizophrenia suffer a wide range of social cognitive deficits, including abnormalities in eye gaze perception. For instance, patients have shown an increased bias to misjudge averted gaze as being directed toward them. In this study we probed early unconscious mechanisms of gaze processing in schizophrenia using a technique known as continuous flash suppression. Previous research using this technique to render faces with direct and averted gaze initially invisible reveals that direct eye contact gains privileged access to conscious awareness in healthy adults. We found that patients, as with healthy control subjects, showed the same effect: faces with direct eye gaze became visible significantly faster than faces with averted gaze. This suggests that early unconscious processing of eye gaze is intact in schizophrenia and implies that any misjudgments of gaze direction must manifest at a later conscious stage of gaze processing where deficits and/or biases in attributing mental states to gaze and/or beliefs about being watched may play a role.

Recent advances in laser in situ keratomileusis-associated dry eye.

PubMed

Xie, Wenjia

2016-03-01

Dry eye is the most common complication after laser in situ keratomileusis (LASIK). The major cause of LASIK-associated dry eye is corneal nerve damage. Early identification and treatment of post-operative dry eye are essential to prevent further ocular surface damage. This article reviews the recent studies of LASIK-associated dry eye, including clinical features, aetiology, risk factors, evaluations and treatment. The applications of novel technologies in LASIK-associated dry eye evaluation like anterior segment spectral-domain optical coherence tomography (SD-OCT) and corneal confocal microscopy are also introduced in this review. © 2016 Optometry Australia.

[Assessment of lipid layer thickness of tear film in the diagnosis of dry-eye syndrome in children after the hematopoietic stem cell transplantation].

PubMed

Kurpińska, Małgorzata; Gorczyńska, Ewa; Owoc-Lempach, Joanna; Bernacka, Aleksandra; Misiuk-Hojło, Marta; Chybicka, Alicja

2011-01-01

Dry eye syndrome (DES), also known as keratoconjunctivitis sicca (KCS) is recognized as the most frequent ocular complication after allogeneic stem cell transplantation (allo-SCT). KCS can appear either due to insufficient tear production or excessive tear evaporation, both resulting in tears hyperosmolarity that leads to ocular damage. The evaporation rate and better film stability is determined primarily by the status of the lipid layer. Observation and classification of tear film lipid layer interference patterns in normal and dry eyes in patients after allogeneic stem cell transplantation with a follow-up time of 6 months-5 years (median 26.54 months). Investigation of the relation between the lipid layer interference patterns in normal and dry eyes and the results of other dry eye examinations and complaints. Relation between DES and conditioning regimes, including total body irradiation and high-dose chemotherapy, immunosuppressive drugs, the time after allogeneic stem cell transplantation and chronic graft-versus-host disease. Precorneal tears lipid layer interference patterns, were examined in 114 eyes in treatment group with the Tearscope-plus. Patient with dry eye were identified on the basis of Schirmer test scores and/or tear breakup time, and positive lissamine and/or fluorescein staining. 42 of 114 eyes (36.8%) developed DES after allo-SCT A significant correlation between thickness of lipid layer and BUT, Schirmer test, lissamine green and fluorescein staining was found in the treatment group. A significant association was found between present chronic GVHD and DES in children. DES was not associated with TBI, corticosteroids, immunosuppressive drugs and the time in the present study. Tears lipid layer interference patterns are highly correlated with the diagnosis of DES. Tears lipid layer interference patterns ( noninvasive method), can be used to diagnose early DES in children after allo-SCT. Chronic GVHD play a major role in development of DES. dry eye syndrome, graft versus host disease, stem cell transplantation.

Anterior Segment Optical Coherence Tomography Angiography for Identification of Iris Vasculature and Staging of Iris Neovascularization: A Pilot Study.

PubMed

Roberts, Philipp K; Goldstein, Debra A; Fawzi, Amani A

2017-08-01

Purpose/Aim of the study: To assess the ability of optical coherence tomographic angiography (OCTA) to visualize the normal iris vasculature as well as neovascularization of the iris (NVI). Study participants with healthy eyes, patients at risk of NVI development and patients with active or regressed NVI were consecutively included in this cross-sectional observational study. Imaging was performed using a commercially available OCTA system (RTVue- XR Avanti, Optovue Inc., Fremont, CA, USA). Abnormal iris vessels were graded on OCTA according to a modified clinical staging system and compared to slitlamp and gonioscopic findings. Fifty eyes of 26 study participants (16 healthy eyes, 19 eyes at risk, 15 eyes with different stages of NVI) were imaged using OCTA. In 11 out of 16 healthy eyes (69%) with light or moderately dark iris pigmentation, we observed physiological, radially aligned iris vasculature on OCTA imaging, which could not be visualized in five eyes (31%) with darkly pigmented irides. One eye in the "eyes at risk" group was diagnosed with NVI based on OCTA, which was not observed clinically. Fifteen eyes with clinically active or regressed NVI were imaged. Different stages of NVI could be differentiated by OCTA, corresponding well to an established clinical grading system. Four eyes showed regressed NVI by OCTA, not seen clinically, and were graded as a newly defined stage 4. This pilot clinical study showed that OCTA for imaging of the iris vasculature in health and disease is highly dependent on iris pigmentation. Fine, clinically invisible iris vessels can be visualized by OCTA in the very early stages as well as in the regressed stage of NVI.

Anterior Segment Optical Coherence Tomography Angiography for Identification of Iris Vasculature and Staging of Iris Neovascularization: A Pilot Study

PubMed Central

Roberts, Philipp K.; Goldstein, Debra A.; Fawzi, Amani A.

2017-01-01

Purpose/Aim of the study To assess the ability of optical coherence tomographic angiography (OCTA) to visualize the normal iris vasculature as well as neovascularization of the iris (NVI). Materials and Methods Study participants with healthy eyes, patients at risk of NVI development and patients with active or regressed NVI were consecutively included in this cross-sectional observational study. Imaging was performed using a commercially available OCTA system (RTVue- XR Avanti, Optovue Inc., Fremont, CA, USA). Abnormal iris vessels were graded on OCTA according to a modified clinical staging system and compared to slitlamp and gonioscopic findings. Results Fifty eyes of 26 study participants (16 healthy eyes, 19 eyes at risk, 15 eyes with different stages of NVI) were imaged using OCTA. In 11 out of 16 healthy eyes (69%) with light or moderately dark iris pigmentation, we observed physiological, radially aligned iris vasculature on OCTA imaging, which could not be visualized in five eyes (31%) with darkly pigmented irides. One eye in the “eyes at risk” group was diagnosed with NVI based on OCTA, which was not observed clinically. Fifteen eyes with clinically active or regressed NVI were imaged. Different stages of NVI could be differentiated by OCTA, corresponding well to an established clinical grading system. Four eyes showed regressed NVI by OCTA, not seen clinically, and were graded as a newly defined stage 4. Conclusions This pilot clinical study showed that OCTA for imaging of the iris vasculature in health and disease is highly dependent on iris pigmentation. Fine, clinically invisible iris vessels can be visualized by OCTA in the very early stages as well as in the regressed stage of NVI. PMID:28441067

Adaptive optics scanning laser ophthalmoscopy for in vivo imaging of lamina cribrosa

NASA Astrophysics Data System (ADS)

Vilupuru, Abhiram S.; Rangaswamy, Nalini V.; Frishman, Laura J.; Smith, Earl L., III; Harwerth, Ronald S.; Roorda, Austin

2007-05-01

The lamina cribrosa has been postulated from in vitro studies as an early site of damage in glaucoma. Prior in vivo measures of laminar morphology have been confounded by ocular aberrations. In this study the lamina cribrosa was imaged after correcting for ocular aberrations using the adaptive optics scanning laser ophthalmoscope (AOSLO) in normal and glaucomatous eyes of rhesus monkeys. All measured laminar morphological parameters showed increased magnitudes in glaucomatous eyes relative to fellow control eyes, indicating altered structure. The AOSLO provides high-quality images of the lamina cribrosa and may have potential as a tool for early identification of glaucoma.

Morphologic analysis of artifacts in human fetal eyes confounding histopathologic investigations.

PubMed

Herwig, Martina C; Müller, Annette M; Holz, Frank G; Loeffler, Karin U

2011-04-25

Human fetal eyes are an excellent source for studies of the normal ocular development and for examining early ocular changes associated with various syndromes in the context of a pediatric pathologic or prenatal sonographic diagnosis. However, artifacts caused by different factors often render an exact interpretation difficult. In this study, the frequency and extent of artifacts in human fetal eyes were investigated with the aim of distinguishing more precisely these artifacts from real findings, allowing also for a more diligent forensic interpretation. The cohort included 341 fetal eyes, ranging in age from 8 to 38 weeks of gestation, that were investigated macroscopically and by light microscopy. In most specimens, artifacts such as pigment spillage and autolytic changes of the retina were noted. Nearly all specimens showed changes of the lens with remarkable similarities to cataractous lenses in adult eyes. Structural ocular changes associated with systemic syndromes were also observed and in most instances could be distinguished from artifacts. Morphologic changes in fetal eyes should be classified in artifacts caused by way of abortion, mechanical effects from the removal of the eyes, delayed fixation with autolysis, and the fixative itself and should be distinguished from genuine structural abnormalities associated with ocular or systemic disease. This classification can be fairly difficult and requires experience. In addition, lens artifacts are often misleading, and the diagnosis of a fetal cataract should not be made based on histopathologic examination alone.

Treatment with sodium hyaluronate eye drops in a patient who had early-onset bleb leakage after trabeculectomy with mitomycin C

PubMed Central

Sagara, Hideto; Sekiryu, Tetsuju; Noji, Hiroki; Ogasawara, Masashi; Imaizumi, Kimihiro; Yago, Keiko

2015-01-01

We present the case of a 47-year-old man who had bilateral proliferative diabetic retinopathy and neovascular glaucoma. Schirmer I test revealed tear secretions of 5 mm and 3 mm in the right and left eyes, respectively. Tear breakup times in the right and left eyes were 7 and 8 seconds, respectively. The ocular surface staining in both eyes was scored as Grade 1 as per the Oxford scheme. Retinal photocoagulation was performed for correction of the proliferative diabetic retinopathy and rubeosis iridis, which resolved with treatment. However, the intraocular pressure in the left eye could not be adequately controlled. Therefore, trabeculectomy with mitomycin C using limbal-based conjunctival flap was performed. Three hours after the surgery, the patient developed a large and diffuse filtering bleb, but no leakage occurred from the conjunctival scar. However, on the first postoperative day, leakage was noted and the conjunctiva was at the leakage point. The leakage resolved transiently, but recurred the next day. Severe keratoconjunctival epithelial failure was detected, and the patient was administrated 0.1% sodium hyaluronate eye drops six times daily. The epithelial failure improved, and many microcysts were detected on the bleb surface where the epithelial failure improved. The leakage resolved 2 days after initiation of the sodium hyaluronate eye drops. The microcysts disappeared and the bleb surface became smooth 1 month later. PMID:26664245

Treatment with sodium hyaluronate eye drops in a patient who had early-onset bleb leakage after trabeculectomy with mitomycin C.

PubMed

Sagara, Hideto; Sekiryu, Tetsuju; Noji, Hiroki; Ogasawara, Masashi; Imaizumi, Kimihiro; Yago, Keiko

2015-01-01

We present the case of a 47-year-old man who had bilateral proliferative diabetic retinopathy and neovascular glaucoma. Schirmer I test revealed tear secretions of 5 mm and 3 mm in the right and left eyes, respectively. Tear breakup times in the right and left eyes were 7 and 8 seconds, respectively. The ocular surface staining in both eyes was scored as Grade 1 as per the Oxford scheme. Retinal photocoagulation was performed for correction of the proliferative diabetic retinopathy and rubeosis iridis, which resolved with treatment. However, the intraocular pressure in the left eye could not be adequately controlled. Therefore, trabeculectomy with mitomycin C using limbal-based conjunctival flap was performed. Three hours after the surgery, the patient developed a large and diffuse filtering bleb, but no leakage occurred from the conjunctival scar. However, on the first postoperative day, leakage was noted and the conjunctiva was at the leakage point. The leakage resolved transiently, but recurred the next day. Severe keratoconjunctival epithelial failure was detected, and the patient was administrated 0.1% sodium hyaluronate eye drops six times daily. The epithelial failure improved, and many microcysts were detected on the bleb surface where the epithelial failure improved. The leakage resolved 2 days after initiation of the sodium hyaluronate eye drops. The microcysts disappeared and the bleb surface became smooth 1 month later.

The Relation of Ocular Surface Irregularity and Visual Disturbance in Early Stage Acanthamoeba Keratitis.

PubMed

Matsumoto, Yukihiro; Kodama, Asako; Goto, Eiki; Kawakita, Tetsuya; Dogru, Murat; Tsubota, Kazuo

2017-01-01

To evaluate the relation between ocular surface irregularity and visual disturbance in early stage Acanthamoeba keratitis (AK). Fifteen patients with culture-proven AK underwent routine ophthalmic examinations, including best-corrected visual acuity (BCVA) measurement, slitlamp biomicroscope examination, and corneal fluorescein dye staining test, in both the eyes. We also evaluated the corneal sensitivity with Cochet-Bonnet esthesiometer, tear functions by Schirmer's test, and ocular surface irregularity by corneal topography and compared the results with the contralateral healthy eyes in this study. The mean logarithm of the minimum angle of resolution BCVA (0.71±0.77) was significantly lower in the eyes with AK (P=0.002). Epithelial disorders were present in all eyes, and radial keratoneuritis in 14 eyes (93.3%). The mean corneal sensitivity (39.3±24.1 mm) was significantly lower in eyes with AK compared with the healthy eyes (P=0.005). The mean Schirmer's test value (22.5±12.0 mm) in eyes with AK was significantly higher compared with the healthy eyes (P=0.01). The ocular surface irregularity indices (the surface regularity index, 2.47±0.42; the surface asymmetry index, 3.24±1.31) were significantly higher in eyes with AK compared with contralateral healthy eyes (P<0.0001 and P<0.0001, respectively). The ocular surface disease in AK is associated with decrease in corneal sensitivity and increase in Schirmer's test value and ocular surface irregularity indices. The visual disturbance in AK may owe not only to corneal haze but also to ocular surface irregularity.

[Treatment of difficult endocrine orbitopathy cases].

PubMed

Breuer, T; Ammann-Rauch, D; Tasman, A J

2007-05-01

There can be many differences between the clinical presentation and disease development of endocrine orbitopathy. Uncommon clinical expressions of the disease may lead to misinterpretations causing difficulties in treatment. Misdiagnosed forms of the disease can end with irreversible vision loss. A 79-year old female with severe bilateral thyroid eye disease, progressive almost blinding visual loss, with the absence of exophthalmos is described. Second, a 39 year old female with a unilateral thyroid eye disease and relapsing episodes of the disease is reported. Exophthalmos, as a symptom, occurs in about 60 % of the patients diagnosed with thyroid eye disease. The absence of exophthalmos may be due to a reduced volume (atrophy ) of retrobulbar fat tissue. Progressive visual loss can be related to direct compression of the optic nerve by thickened eye muscles in the orbital apex. Thyroid eye disease presents itself unilaterally in 5-11 % of all cases and involvement of the contra lateral orbit may occur years later. A relapse of the disease may be triggered by episodes of hypo- or hyperthyroidism. Smoking is a significant risk factor for orbitopathy relapse. Physicians treating thyroid eye disease should be aware of atypical clinical presentations in order for early satisfactory treatment. An interdisciplinary approach including ophthalmologists, endocrinologists and oto-rhino-laryngologists is necessary for optimal management.

Fixation to features and neural processing of facial expressions in a gender discrimination task.

PubMed

Neath, Karly N; Itier, Roxane J

2015-10-01

Early face encoding, as reflected by the N170 ERP component, is sensitive to fixation to the eyes. Whether this sensitivity varies with facial expressions of emotion and can also be seen on other ERP components such as P1 and EPN, was investigated. Using eye-tracking to manipulate fixation on facial features, we found the N170 to be the only eye-sensitive component and this was true for fearful, happy and neutral faces. A different effect of fixation to features was seen for the earlier P1 that likely reflected general sensitivity to face position. An early effect of emotion (∼120 ms) for happy faces was seen at occipital sites and was sustained until ∼350 ms post-stimulus. For fearful faces, an early effect was seen around 80 ms followed by a later effect appearing at ∼150 ms until ∼300 ms at lateral posterior sites. Results suggests that in this emotion-irrelevant gender discrimination task, processing of fearful and happy expressions occurred early and largely independently of the eye-sensitivity indexed by the N170. Processing of the two emotions involved different underlying brain networks active at different times. Copyright © 2015 Elsevier Inc. All rights reserved.

Differential Attention to Faces in Infant Siblings of Children with Autism Spectrum Disorder and Associations with Later Social and Language Ability.

PubMed

Wagner, Jennifer B; Luyster, Rhiannon J; Moustapha, Hana; Tager-Flusberg, Helen; Nelson, Charles A

2018-01-01

A growing body of literature has begun to explore social attention in infant siblings of children with autism spectrum disorder (ASD) with hopes of identifying early differences that are associated with later ASD or other aspects of development. The present study used eye-tracking to familiar (mother) and unfamiliar (stranger) faces in two groups of 6-month-old infants: infants with no family history of ASD (low-risk controls; LRC), and infants at high risk for ASD (HRA), by virtue of having an older sibling with ASD. HRA infants were further characterized based on autism classification at 24 months or older as HRA- (HRA without an ASD outcome) or HRA+ (HRA with an ASD outcome). For time scanning faces overall, HRA+ and LRC showed similar patterns of attention, and this was significantly greater than in HRA-. When examining duration of time spent on eyes and mouth, all infants spent more time on eyes than mouth, but HRA+ showed the greatest amount of time looking at these regions, followed by LRC, then HRA-. LRC showed a positive association between 6-month attention to eyes and 18-month social-communicative behavior, while HRA- showed a negative association between attention to eyes at 6 months and expressive language at 18 months (all correlations controlled for non-verbal IQ; HRA- correlations held with and without the inclusion of the small sample of HRA+). Differences found in face scanning at 6 months, as well as associations with social communication at 18 months, point to potential variation in the developmental significance of early social attention in children at low and high risk for ASD.

BMP signaling protects telencephalic fate by repressing eye identity and its Cxcr4-dependent morphogenesis.

PubMed

Bielen, Holger; Houart, Corinne

2012-10-16

Depletion of Wnt signaling is a major requirement for the induction of the anterior prosencephalon. However, the molecular events driving the differential regionalization of this area into eye-field and telencephalon fates are still unknown. Here we show that the BMP pathway is active in the anterior neural ectoderm during late blastula to early gastrula stage in zebrafish. Bmp2b mutants and mosaic loss-of-function experiments reveal that BMP acts as a repressor of eye-field fate through inhibition of its key transcription factor Rx3, thereby protecting the future telencephalon from acquiring eye identity. This BMP-driven mechanism initiates the establishment of the telencephalon prior to the involvement of Wnt antagonists from the anterior neural border. Furthermore, we demonstrate that Rx3 and BMP are respectively required to maintain and restrict the chemokine receptor cxcr4a, which in turn contributes to the morphogenetic separation of eye-field and telencephalic cells during early neurulation. Copyright © 2012 Elsevier Inc. All rights reserved.

The Rate of Visual Field Change in the Ocular Hypertension Treatment Study

PubMed Central

De Moraes, Carlos Gustavo V.; Gardiner, Stuart K.; Liebmann, Jeffrey M.; Cioffi, George A.; Ritch, Robert; Gordon, Mae O.; Kass, Michael A.

2012-01-01

Purpose. To assess the rate of change of visual field (VF) mean deviation (MD) in the Ocular Hypertension Treatment Study (OHTS). Methods. OHTS data were filtered to exclude eyes that had fewer than 10 reliable VFs or less than 5 years of follow-up or that reached a nonglaucomatous endpoint. The rate of change of MD (MDR) was calculated for each eye. Differences were sought between groups of eyes differing in primary open angle glaucoma (POAG) outcome, how POAG was determined, and original randomization. Results. In total, 2609 eyes (1379 participants) met the selection criteria. The mean MDR was −0.08 ± 0.20 dB/y (±SD). POAG eyes (n = 359) had significantly worse MDRs (−0.26 ± 0.36 dB/y) than non-POAG eyes (n = 2250; −0.05 ± 0.14 dB/y; P < 0.001). Eyes that reached POAG endpoints based on only VF change (n = 74; −0.29 ± 0.31 dB/y) or only optic disc change (n = 158; −0.12 ± 0.19 dB/y) had significantly worse MDRs than non-POAG eyes (both P < 0.001). Eyes that reached POAG endpoints for both VF and optic disc change (n = 127) deteriorated more rapidly (−0.42 ± 0.46 dB/y) than eyes showing only VF change (P = 0.017) or only optic disc change (P < 0.001). There was not a significant association between MDR and original OHTS randomization (observe vs. treat, P = 0.168). Conclusions. Eyes that develop POAG have significantly worse MDRs than eyes that do not. Eyes that reached endpoints due to both VF and optic disc change had worse MDRs than eyes displaying change in only one of these. MDR was not significantly associated with randomization, suggesting that MDR may not be the best measure of VF change in early-stage POAG. (ClinicalTrials.gov number, NCT00000125.) PMID:22159015

Eye movement disorders are an early manifestation of CACNA1A mutations in children.

PubMed

Tantsis, Esther M; Gill, Deepak; Griffiths, Lyn; Gupta, Sachin; Lawson, John; Maksemous, Neven; Ouvrier, Robert; Riant, Florence; Smith, Robert; Troedson, Christopher; Webster, Richard; Menezes, Manoj P

2016-06-01

The alpha-1 isoform of the calcium channel gene is expressed abundantly in neuronal tissue, especially within the cerebellum. Mutations in this gene may manifest with hemiplegic migraine, spinocerebellar ataxia type 6 (SCA6) and episodic ataxia type 2 (EA2) in adults. There are reports of children with CACAN1A mutations presenting with paroxysmal tonic upgaze, abnormal saccades and congenital nystagmus as well as severe forms of hemiplegic migraine. The aim of this study was to review the clinical presentation and subsequent course of all children with a CACNA1A mutation who presented to a tertiary children's hospital. We reviewed retrospectively nine children with a proven CACNA1A mutation who presented to the Children's Hospital at Westmead between 2005-2015. The initial and subsequent clinical presentation, radiological features and molecular genetic profile of each child was reviewed. Nine children presented to out institute over a 10 year period; six were female and three male. The median age of presentation was 1.2 years. Eye movement disorders were the presenting feature in eight children. Three of these children later presented with severe hemiplegic migraine episodes often requiring ICU care. Affected children also had developmental delay and developed classical hemiplegic migraine, episodic ataxia and seizures. Calcium channel blockers were used with some efficacy in preventing severe HM episodes. Eye movement disorders are an early manifestation of CACNA1A mutations in children. Improved recognition of the CACNA1A phenotype in childhood is important for early diagnosis, counselling and appropriate emergency management. There is some early evidence that calcium channel blockers may be an effective prophylactic agent for the severe hemiplegic migraine episodes. © 2016 Mac Keith Press.

Indocyanine green angiography of juvenile X-linked retinoschisis.

PubMed

Souied, Eric H; Goritsa, Anna; Querques, Giuseppe; Coscas, Gabriel; Soubrane, Gisele

2005-09-01

In juvenile X-linked retinoschisis (XLRS), fluorescein angiography is usually unremarkable and contributes poorly to the diagnosis. However, indocyanine green (ICG) angiography features in eyes that are affected with XLRS were not yet described. Retrospective observational case series. A complete ophthalmologic examination that included ICG angiography was performed on three unrelated male patients (six eyes) who were 15, 22, and 48 years old. A distinct hyperfluorescent stellate pattern in the macular area that was associated with radial lines of hypofluorescence that were centered on the foveola was observed on the early phase of ICG examination (six of six eyes). This feature disappeared on the late phase of ICG examination. On these six XLRS eyes, early phases of ICG examination revealed an unusual radial aspect on the macula. This finding suggests that ICG angiography may be useful for the diagnosis of XLRS.

Disruption of Msx-1 and Msx-2 reveals roles for these genes in craniofacial, eye, and axial development.

PubMed

Foerst-Potts, L; Sadler, T W

1997-05-01

In mouse embryos, the muscle segment homeobox genes, Msx-1 and Msx-2 are expressed during critical stages of neural tube, neural crest, and craniofacial development, suggesting that these genes play important roles in organogenesis and cell differentiation. Although the patterns of expression are intriguing, little is known about the function of these genes in vertebrate embryonic development. Therefore, the expression of both genes, separately and together, was disrupted using antisense oligodeoxynucleotides and whole embryo culture techniques. Antisense attenuation of Msx-1 during early stages of neurulation produced hypoplasia of the maxillary, mandibular, and frontonasal prominences, eye anomalies, and somite and neural tube abnormalities. Eye defects consisted of enlarged optic vesicles, which may ultimately result in micropthalmia similar to that observed in Small eye mice homozygous for mutations in the Pax-6 gene. Histological sections and SEM analysis revealed a thinning of the neuroepithelium in the diencephalon and optic vesicle and mesenchymal deficiencies in the craniofacial region. Injections of Msx-2 antisense oligodeoxynucleotides produced similar malformations as those targeting Msx-1, with the exception that there was an increase in number and severity of neural tube and somite defects. Embryos injected with the combination of Msx-1 + Msx-2 antisense oligodeoxynucleotides showed no novel abnormalities, suggesting that the genes do not operate in a redundant manner.

Detecting early functional damage in glaucoma suspect and ocular hypertensive patients with the multifocal VEP technique.

PubMed

Thienprasiddhi, Phamornsak; Greenstein, Vivienne C; Chu, David H; Xu, Li; Liebmann, Jeffrey M; Ritch, Robert; Hood, Donald C

2006-08-01

To determine whether the multifocal visual evoked potential (mfVEP) technique can detect early functional damage in ocular hypertensive (OHT) and glaucoma suspect (GS) patients with normal standard achromatic automated perimetry (SAP) results. Twenty-five GS patients (25 eyes), 25 patients with OHT (25 eyes), and 50 normal controls (50 eyes) were enrolled in this study. All GS, OHT and normal control eyes had normal SAP as defined by a pattern standard deviation and mean deviation within the 95% confidence interval and a glaucoma hemifield test within normal limits on the Humphrey visual field 24-2 program. Eyes with GS had optic disc changes consistent with glaucoma with or without raised intraocular pressure (IOP), and eyes with OHT showed no evidence of glaucomatous optic neuropathy and IOPs >or=22 mm Hg. Monocular mfVEPs were obtained from both eyes of each subject using a pattern-reversal dartboard array with 60 sectors. The entire display had a radius of 22.3 degrees. The mfVEPs, for each eye, were defined as abnormal when either the monocular or interocular probability plot had a cluster of 3 or more contiguous points with P<0.05 and at least 2 of these points with P<0.01. The mfVEP results were abnormal in 4% of the eyes from normal subjects. Abnormal mfVEPs were detected in 20% of the eyes of GS patients and 16% of the eyes of OHT patients. Significantly more mfVEP abnormalities were detected in GS patients than in normal controls. However, there was no significant difference in mfVEP results between OHT patients and normal controls. The mfVEP technique can detect visual field deficits in a minority of eyes with glaucomatous optic disks and normal SAP results.

Interactive Whiteboard Professional Development: A Look through the Eyes of Early Childhood Educators

ERIC Educational Resources Information Center

Evans, Nicole Southerland

2012-01-01

With vastly ever-changing technology, there come greater possibilities in the school classroom. One possibility includes the interactive whiteboard, IWB (Higgins, Beauchamp, & Miller, 2007). However, there is little research on how to effectively promote the use of an IWB in the classroom for anything other than as a mediating tool. One option…

The Slow Developmental Time Course of Real-Time Spoken Word Recognition

ERIC Educational Resources Information Center

Rigler, Hannah; Farris-Trimble, Ashley; Greiner, Lea; Walker, Jessica; Tomblin, J. Bruce; McMurray, Bob

2015-01-01

This study investigated the developmental time course of spoken word recognition in older children using eye tracking to assess how the real-time processing dynamics of word recognition change over development. We found that 9-year-olds were slower to activate the target words and showed more early competition from competitor words than…

Retinal laser burn (RLB) induced neuropathy leads to substance P dependent loss of ocular immune privilege

PubMed Central

Lucas, Kenyatta; Karamichos, Dimitris; Mathew, Rose; Zieske, James D.; Stein-Streilein, Joan

2012-01-01

Inflammation in the eye is tightly regulated by multiple mechanisms that together contribute to ocular immune privilege. Many studies have shown that it is very difficult to abrogate the immune privileged mechanism called anterior chamber associated immune deviation (ACAID). Previously, we showed that retinal laser burn (RLB) to one eye abrogated immune privilege (ACAID) bilaterally for an extended period of time. In an effort to explain the inflammation in the non-burned eye, we postulated that neuronal signals initiated inflammation in the contralateral eye. Here, we test the role of substance P, a neuroinflamatory peptide, in RLB-induced loss of ACAID. Histological examination of the retina with and without RLB revealed an increase of the substance P-inducible neurokinin 1 receptor (NK1-R) in the retina of first, the burned eye, and then the contralateral eye. Specific antagonists for NK1-R, given locally with antigen within 24h, but not 3,5, or 7 days post RLB treatment, prevented the bilateral loss of ACAID. Substance P Knockout (KO) mice retained their ability to develop ACAID post RLB. These data support the postulate that substance P transmits early inflammatory signals from the RLB eye to the contralateral eye to induce changes to ocular immune privilege and has a central role in the bilateral loss of ACAID. The possibility is raised that blocking of the substance P pathway with NK1-R antagonists post ocular trauma may prevent unwanted and perhaps extended consequences of trauma-induced inflammation in the eye. PMID:22745377

Shorter spontaneous fixation durations in infants with later emerging autism.

PubMed

Wass, Sam V; Jones, Emily J H; Gliga, Teodora; Smith, Tim J; Charman, Tony; Johnson, Mark H

2015-02-06

Little is known about how spontaneous attentional deployment differs on a millisecond-level scale in the early development of autism spectrum disorders (ASD). We measured fine-grained eye movement patterns in 6-to 9-month-old infants at high or low familial risk (HR/LR) of ASD while they viewed static images. We observed shorter fixation durations (i.e. the time interval between saccades) in HR than LR infants. Preliminary analyses indicate that these results were replicated in a second cohort of infants. Fixation durations were shortest in those infants who went on to receive an ASD diagnosis at 36 months. While these findings demonstrate early-developing atypicality in fine-grained measures of attentional deployment early in the etiology of ASD, the specificity of these effects to ASD remains to be determined.

Content Design and System Implementation of a Teleophthalmology System for Eye Disease Diagnosis and Treatment and Its Preliminary Practice in Guangdong, China.

PubMed

Xiao, Di; Vignarajan, Janardhan; Chen, Tingting; Ye, Tiantian; Xiao, Baixiang; Congdon, Nathan; Kanagasingam, Yogessan

2017-12-01

We have developed a new telemedicine system for comprehensive eye examination, diabetic retinopathy (DR) screening, and eye disease diagnosis and treatment. The novel points of the system include a tablet application for facilitating doctor's examination and diagnosis process, a comprehensive eye examination component, and integrated treatment planning and recording. The system provided a new service model through one ophthalmological center linking with multiple remote and rural hospitals for eye care in Guangdong province, China. The early stage of the project study also undertook the responsibility of educations for remote-area doctors and image graders for DR grading and glaucoma grading and research on the effectiveness of short message service (SMS) reminder for patient revisit. Some other research, such as the comparison of the accuracy of graders' DR grading with the gold standard, and doctor's tentative diagnosis with final diagnosis and related statistical information, has been implemented in the system. In the preliminary practice, we summarized the outcomes related to presenting system performance and made an initial analysis. From the practice, the project has shown the telemedicine system and associated contents have satisfied our initial goal and demonstrated their effectiveness and efficiency.

Eye-Tracking as a Measure of Responsiveness to Joint Attention in Infants at Risk for Autism

ERIC Educational Resources Information Center

Navab, Anahita; Gillespie-Lynch, Kristen; Johnson, Scott P.; Sigman, Marian; Hutman, Ted

2012-01-01

Reduced responsiveness to joint attention (RJA), as assessed by the Early Social Communication Scales (ESCS), is predictive of both subsequent language difficulties and autism diagnosis. Eye-tracking measurement of RJA is a promising prognostic tool because it is highly precise and standardized. However, the construct validity of eye-tracking…

Molecular Evolution of Spider Vision: New Opportunities, Familiar Players.

PubMed

Morehouse, Nathan I; Buschbeck, Elke K; Zurek, Daniel B; Steck, Mireille; Porter, Megan L

2017-08-01

Spiders are among the world's most species-rich animal lineages, and their visual systems are likewise highly diverse. These modular visual systems, composed of four pairs of image-forming "camera" eyes, have taken on a huge variety of forms, exhibiting variation in eye size, eye placement, image resolution, and field of view, as well as sensitivity to color, polarization, light levels, and motion cues. However, despite this conspicuous diversity, our understanding of the genetic underpinnings of these visual systems remains shallow. Here, we review the current literature, analyze publicly available transcriptomic data, and discuss hypotheses about the origins and development of spider eyes. Our efforts highlight that there are many new things to discover from spider eyes, and yet these opportunities are set against a backdrop of deep homology with other arthropod lineages. For example, many (but not all) of the genes that appear important for early eye development in spiders are familiar players known from the developmental networks of other model systems (e.g., Drosophila). Similarly, our analyses of opsins and related phototransduction genes suggest that spider photoreceptors employ many of the same genes and molecular mechanisms known from other arthropods, with a hypothesized ancestral spider set of four visual and four nonvisual opsins. This deep homology provides a number of useful footholds into new work on spider vision and the molecular basis of its extant variety. We therefore discuss what some of these first steps might be in the hopes of convincing others to join us in studying the vision of these fascinating creatures.

Altered gene expression in dry age-related macular degeneration suggests early loss of choroidal endothelial cells.

PubMed

Whitmore, S Scott; Braun, Terry A; Skeie, Jessica M; Haas, Christine M; Sohn, Elliott H; Stone, Edwin M; Scheetz, Todd E; Mullins, Robert F

2013-01-01

Age-related macular degeneration (AMD) is a major cause of blindness in developed countries. The molecular pathogenesis of early events in AMD is poorly understood. We investigated differential gene expression in samples of human retinal pigment epithelium (RPE) and choroid from early AMD and control maculas with exon-based arrays. Gene expression levels in nine human donor eyes with early AMD and nine control human donor eyes were assessed using Affymetrix Human Exon ST 1.0 arrays. Two controls did not pass quality control and were removed. Differentially expressed genes were annotated using the Database for Annotation, Visualization and Integrated Discovery (DAVID), and gene set enrichment analysis (GSEA) was performed on RPE-specific and endothelium-associated gene sets. The complement factor H (CFH) genotype was also assessed, and differential expression was analyzed regarding high AMD risk (YH/HH) and low AMD risk (YY) genotypes. Seventy-five genes were identified as differentially expressed (raw p value <0.01; ≥50% fold change, mean log2 expression level in AMD or control ≥ median of all average gene expression values); however, no genes were significant (adj. p value <0.01) after correction for multiple hypothesis testing. Of 52 genes with decreased expression in AMD (fold change <0.5; raw p value <0.01), 18 genes were identified by DAVID analysis as associated with vision or neurologic processes. The GSEA of the RPE-associated and endothelium-associated genes revealed a significant decrease in genes typically expressed by endothelial cells in the early AMD group compared to controls, consistent with previous histologic and proteomic studies. Analysis of the CFH genotype indicated decreased expression of ADAMTS9 in eyes with high-risk genotypes (fold change = -2.61; raw p value=0.0008). GSEA results suggest that RPE transcripts are preserved or elevated in early AMD, concomitant with loss of endothelial cell marker expression. These results are consistent with the notion that choroidal endothelial cell dropout or dedifferentiation occurs early in the pathogenesis of AMD.

Ocular static and dynamic light scattering: a noninvasive diagnostic tool for eye research and clinical practice

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.

2004-01-01

The noninvasive techniques of static and dynamic light scattering are emerging as valuable diagnostic tools for the early detection of ocular and systemic diseases. These include corneal abnormalities, pigmentary dispersion syndrome, glaucoma, cataract, diabetic vitreopathy, and possibly macular degeneration. Systemic conditions such as diabetes and possibly Alzheimer's disease can potentially be detected early via ocular tissues. The current state of development of these techniques for application to ophthalmic research and ultimately clinical practice is reviewed. (c) 2004 Society of Photo-Optical Instrumentation Engineers.

Low Vision Research at the Schepens Eye Research Institute

DTIC Science & Technology

2003-07-01

subjects is completed. Project 5 is also a continuation of the identification of factors that can predict dry eye complications of LASIK surgery. Patient enrollment is proceeding well and early analyses are complete.

Diagnostic Ability of Wide-field Retinal Nerve Fiber Layer Maps Using Swept-Source Optical Coherence Tomography for Detection of Preperimetric and Early Perimetric Glaucoma.

PubMed

Lee, Won June; Na, Kyeong Ik; Kim, Young Kook; Jeoung, Jin Wook; Park, Ki Ho

2017-06-01

To evaluate the diagnostic ability of wide-field retinal nerve fiber layer (RNFL) maps with swept-source optical coherence tomography (SS-OCT) for detection of preperimetric (PPG) and early perimetric glaucoma (EG). One hundred eighty-four eyes, including 67 healthy eyes, 43 eyes with PPG, and 74 eyes with EG, were analyzed. Patients underwent a comprehensive ocular examination including red-free RNFL photography, visual field testing and wide-field SS-OCT scanning (DRI-OCT-1 Atlantis; Topcon, Tokyo, Japan). SS-OCT provides a wide-field RNFL thickness map and a SuperPixel map, which are composed of the RNFL deviation map of the peripapillary area and the deviation map of the composition of the ganglion cell layer with the inner plexiform layer and RNFL (GC-IPL+RNFL) in the macular area. The ability to discriminate PPG and EG from healthy eyes was assessed using sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) for all parameters and criteria provided by the wide-field SS-OCT scan. The wide-field RNFL thickness map using SS-OCT showed the highest sensitivity of PPG-diagnostic and EG-diagnostic performance compared with the other SS-OCT criteria based on the internal normative base (93.0 and 97.3%, respectively). Among the SS-OCT continuous parameters, the RFNL thickness of the 7 clock-hour, inferior and inferotemporal macular ganglion cell analyses showed the largest AUC of PPG-diagnostic and EG-diagnostic performance (AUC=0.809 to 0.865). The wide-field RNFL thickness map using SS-OCT performed well in distinguishing eyes with PPG and EG from healthy eyes. In the clinical setting, wide-field RNFL maps of SS-OCT can be useful tools for detection of early-stage glaucoma.

Orientation Discrimination with Macular Changes Associated with Early AMD

PubMed Central

Bedell, Harold E.; Tong, Jianliang; Woo, Stanley Y.; House, Jon R.; Nguyen, Tammy

2010-01-01

Purpose Age-related macular degeneration (AMD) is a condition that progressively reduces central vision in elderly individuals, resulting in a reduced capacity to perform many daily activities and a diminished quality of life. Recent studies identified clinical treatments that can slow or reverse the progression of exudative (wet) AMD and ongoing research is evaluating earlier interventions. Because early diagnosis is critical for an optimal outcome, the goal of this study is to assess psychophysical orientation discrimination for randomly positioned short line segments as a potential indicator of subtle macular changes in eyes with early AMD. Methods Orientation discrimination was measured in a sample of 74 eyes of patients aged 47 to 82 years old, none of which had intermediate or advanced AMD. Amsler-grid testing was performed as well. A masked examiner graded each eye as level 0, 1, 2, or 3 on a streamlined version of the Age-Related Eye Disease Study (AREDS) scale for AMD, based on the presence and extent of macular drusen or retinal pigment epithelium (RPE) changes. Visual acuity in the 74 eyes ranged from 20/15 to 20/40+1, with no significant differences among the grading levels. Humphrey 10–2 and Nidek MP-1 micro-perimetry were used to assess retinal sensitivity at test locations 1° from the locus of fixation. Results Average orientation-discrimination thresholds increased systematically from 7.4° to 11.3° according to the level of macular changes. In contrast, only 3 of 74 eyes exhibited abnormalities on the Amsler grid and central-field perimetric defects occurred with approximately equal probability at all grading levels. Conclusions In contrast to Amsler grid and central-visual-field testing, psychophysical orientation discrimination has the capability to distinguish between eyes with and without subtle age-related macular changes. PMID:19319009

Retinotopic maps and foveal suppression in the visual cortex of amblyopic adults.

PubMed

Conner, Ian P; Odom, J Vernon; Schwartz, Terry L; Mendola, Janine D

2007-08-15

Amblyopia is a developmental visual disorder associated with loss of monocular acuity and sensitivity as well as profound alterations in binocular integration. Abnormal connections in visual cortex are known to underlie this loss, but the extent to which these abnormalities are regionally or retinotopically specific has not been fully determined. This functional magnetic resonance imaging (fMRI) study compared the retinotopic maps in visual cortex produced by each individual eye in 19 adults (7 esotropic strabismics, 6 anisometropes and 6 controls). In our standard viewing condition, the non-tested eye viewed a dichoptic homogeneous mid-level grey stimulus, thereby permitting some degree of binocular interaction. Regions-of-interest analysis was performed for extrafoveal V1, extrafoveal V2 and the foveal representation at the occipital pole. In general, the blood oxygenation level-dependent (BOLD) signal was reduced for the amblyopic eye. At the occipital pole, population receptive fields were shifted to represent more parafoveal locations for the amblyopic eye, compared with the fellow eye, in some subjects. Interestingly, occluding the fellow eye caused an expanded foveal representation for the amblyopic eye in one early-onset strabismic subject with binocular suppression, indicating real-time cortical remapping. In addition, a few subjects actually showed increased activity in parietal and temporal cortex when viewing with the amblyopic eye. We conclude that, even in a heterogeneous population, abnormal early visual experience commonly leads to regionally specific cortical adaptations.

Helicoid peripapillary chorioretinal degeneration complicated by choroidal neovascularization.

PubMed

Triantafylla, Magdalini; Panos, Georgios D; Dardabounis, Doukas; Nanos, Panagiotis; Konstantinidis, Aristeidis

2016-02-15

Helicoid peripapillary chorioretinal degeneration (HPCD) is a hereditary disease of the fundus that is characterized by atrophic chorioretinal areas that appear early in life and expand gradually from the optic disc towards the macula and the periphery. We describe the case of an elderly man with a known diagnosis of HPCD who developed choroidal neovascular membrane (CNV) in both eyes during the course of the disease. The patient was treated with intravitreal injection of ranibizumab, to which he had excellent response. The CNV subsided with 2 injections in the right eye and 1 in the left. Two years after the initial diagnosis of CNV in the right eye, visual acuity was 5/10 OD and 9/10 OS. Helicoid peripapillary chorioretinal degeneration is rarely complicated by CNV as the fundus lacks the trigger factors that would sustain this process. Although rare, HPCD complicated by CNV can be seen bilaterally, but responds well to few ranibizumab injections.

Anterior ischemic optic neuropathy in a patient with Churg-Strauss syndrome.

PubMed

Lee, Ji Eun; Lee, Seung Uk; Kim, Soo Young; Jang, Tae Won; Lee, Sang Joon

2012-12-01

We describe a patient with Churg-Strauss syndrome who developed unilateral anterior ischemic optic neuropathy. A 54-year-old man with a history of bronchial asthma, allergic rhinitis, and sinusitis presented with sudden decreased visual acuity in his right eye that had begun 2 weeks previously. The visual acuity of his right eye was 20 / 50. Ophthalmoscopic examination revealed a diffusely swollen right optic disc and splinter hemorrhages at its margin. Goldmann perimetry showed central scotomas in the right eye and fluorescein angiography showed remarkable hyperfluorescence of the right optic nerve head. Marked peripheral eosinphilia, extravascular eosinophils in a bronchial biopsy specimen, and an increased sedimentation rate supported the diagnosis of Churg-Strauss syndrome. Therapy with methylprednisolone corrected the laboratory abnormalities, improved clinical features, and preserved vision, except for the right central visual field defect. Early recognition of this systemic disease by ophthalmologists may help in preventing severe ocular complications.

Anterior Ischemic Optic Neuropathy in a Patient with Churg-Strauss Syndrome

PubMed Central

Lee, Ji Eun; Lee, Seung Uk; Kim, Soo Young; Jang, Tae Won

2012-01-01

We describe a patient with Churg-Strauss syndrome who developed unilateral anterior ischemic optic neuropathy. A 54-year-old man with a history of bronchial asthma, allergic rhinitis, and sinusitis presented with sudden decreased visual acuity in his right eye that had begun 2 weeks previously. The visual acuity of his right eye was 20 / 50. Ophthalmoscopic examination revealed a diffusely swollen right optic disc and splinter hemorrhages at its margin. Goldmann perimetry showed central scotomas in the right eye and fluorescein angiography showed remarkable hyperfluorescence of the right optic nerve head. Marked peripheral eosinphilia, extravascular eosinophils in a bronchial biopsy specimen, and an increased sedimentation rate supported the diagnosis of Churg-Strauss syndrome. Therapy with methylprednisolone corrected the laboratory abnormalities, improved clinical features, and preserved vision, except for the right central visual field defect. Early recognition of this systemic disease by ophthalmologists may help in preventing severe ocular complications. PMID:23204805

Noninvasive two-photon fluorescence microscopy imaging of mouse retina and RPE through the pupil of the eye

PubMed Central

Palczewska, Grazyna; Dong, Zhiqian; Golczak, Marcin; Hunter, Jennifer J.; Williams, David R.; Alexander, Nathan S.; Palczewski, Krzysztof

2014-01-01

Two-photon excitation microscopy (TPM) can image retinal molecular processes in vivo. Intrinsically fluorescent retinyl esters in sub-cellular structures called retinosomes are an integral part of the visual chromophore regeneration pathway. Fluorescent condensation products of all–trans–retinal accumulate in the eye with age and are also associated with age-related macular degeneration (AMD). Here we report repetitive, dynamic imaging of these compounds in live mice, through the pupil of the eye. Leveraging advanced adaptive optics we developed a data acquisition algorithm that permitted the identification of retinosomes and condensation products in the retinal pigment epithelium (RPE) by their characteristic localization, spectral properties, and absence in genetically modified or drug-treated mice. This imaging approach has the potential to detect early molecular changes in retinoid metabolism that trigger light and AMD-induced retinal defects and to assess the effectiveness of treatments for these conditions. PMID:24952647

A characterization of Parkinson's disease by describing the visual field motion during gait

NASA Astrophysics Data System (ADS)

Trujillo, David; Martínez, Fabio; Atehortúa, Angélica; Alvarez, Charlens; Romero, Eduardo

2015-12-01

An early diagnosis of Parkinson's Disease (PD) is crucial towards devising successful rehabilitation programs. Typically, the PD diagnosis is performed by characterizing typical symptoms, namely bradykinesia, rigidity, tremor, postural instability or freezing gait. However, traditional examination tests are usually incapable of detecting slight motor changes, specially for early stages of the pathology. Recently, eye movement abnormalities have correlated with early onset of some neurodegenerative disorders. This work introduces a new characterization of the Parkinson disease by describing the ocular motion during a common daily activity as the gait. This paper proposes a fully automatic eye motion analysis using a dense optical flow that tracks the ocular direction. The eye motion is then summarized using orientation histograms constructed during a whole gait cycle. The proposed approach was evaluated by measuring the χ2 distance between the orientation histograms, showing substantial differences between control and PD patients.

Phacoemulsification in pseudoexfoliation syndrome.

PubMed

Akinci, Arsen; Batman, Cosar; Zilelioglu, Orhan

2008-01-01

To compare the incidence of intraoperative and early postoperative complications (IEPC), visual outcomes, and change in intraocular pressure (IOP) between eyes with and without pseudoexfoliation syndrome (PEX) having cataract extraction by phacoemulsification. 800 eyes with PEX and 1,600 eyes without PEX having cataract extraction by phacoemulsification were included in this retrospective study. Evaluated parameters were incidence of IEPC, visual outcomes and change in IOP. chi2 and Student's t test were used for statistical analysis. There were no significant differences in the incidence of IEPC and visual acuity gain between the two groups (p > 0.05). Rise in IOP in the early postoperative period was significantly higher in the PEX group (p < 0.02). Patients with PEX who have phacoemulsification can achieve results similar to patients without PEX. IOP control in the early postoperative period seems to be more important in patients with PEX. Copyright 2008 S. Karger AG, Basel.

Early Clinical Features of Pseudoexfoliation Syndrome in Anterior Segment and Gonioscopy Examination.

PubMed

Gür Güngör, Sirel; Bayer, Atilla; Akman, Ahmet; Asena, Leyla

2017-01-01

To determine the early signs of pseudoexfoliation (PEX) in fellow eyes of cases with unilateral PEX. Fellow eyes of 34 cases with unilateral PEX were evaluated by slit-lamp and gonioscopy. Findings associated with PEX were recorded. Mean age was 67.8±8.1 years (range 55-86 years). Twenty-five patients (73.5%) had pigmentation in the inferior angle and 23 patients (67.6%) had Sampaolesi's line located on the inferior angle in fellow eyes. The other most common findings were loss of peripupillary ruff in 10 patients (29.4%) and pigment dispersion following pupil dilation in 14 patients (41.1%). Pigmentation in the inferior angle and Sampaolesi's line on the inferior angle seem to be the most common early findings associated with PEX. Special attention should be paid to these findings in cases with ocular hypertension for proper management.

Biracial and monoracial infant own-race face perception: an eye tracking study.

PubMed

Gaither, Sarah E; Pauker, Kristin; Johnson, Scott P

2012-11-01

We know that early experience plays a crucial role in the development of face processing, but we know little about how infants learn to distinguish faces from different races, especially for non-Caucasian populations. Moreover, it is unknown whether differential processing of different race faces observed in typically studied monoracial infants extends to biracial infants as well. Thus, we investigated 3-month-old Caucasian, Asian and biracial (Caucasian-Asian) infants' ability to distinguish Caucasian and Asian faces. Infants completed two within-subject, infant-controlled habituation sequences and test trials as an eye tracker recorded looking times and scanning patterns. Examination of individual differences revealed significant positive correlations between own-race novelty preference and scanning frequency between eye and mouth regions of own-race habituation stimuli for Caucasian and Asian infants, suggesting that facility in own-race face discrimination stems from active inspection of internal facial features in these groups. Biracial infants, however, showed the opposite effect: An 'own-race' novelty preference was associated with reduced scanning between eye and mouth regions of 'own-race' habituation stimuli, suggesting that biracial infants use a distinct approach to processing frequently encountered faces. Future directions for investigating face processing development in biracial populations are discussed. © 2012 Blackwell Publishing Ltd.

Pediatric vision screening using binocular retinal birefringencr scanning

NASA Astrophysics Data System (ADS)

Nassif, Deborah S.; Gramatikov, Boris; Guyton, David L.; Hunter, David G.

2003-07-01

Amblyopia, a leading cause of vision loss in childhood, is responsive to treatment if detected early in life. Risk factors for amblyopia, such as refractive error and strabismus, may be difficult to identify clinically in young children. Our laboratory has developed retinal birefringence scanning (RBS), in which a small spot of polarized light is scanned in a circle on the retina, and the returning light is measured for changes in polarization caused by the pattern of birefringent fibers that comprise the fovea. Binocular RBS (BRBS) detects the fixation of both eyes simultaneously and thus screens for strabismus, one of the risk factors of amblyopia. We have also developed a technique to automatically detect when the eye is in focus without measuring refractive error. This focus detection system utilizes a bull's eye photodetector optically conjugate to a point fixation source. Reflected light is focused back to the point source by the optical system of the eye, and if the subject focuses on the fixation source, the returning light will be focused on the detector. We have constructed a hand-held prototype combining BRBS and focus detection measurements in one quick (< 0.5 second) and accurate (theoretically detecting +/-1 of misalignment) measurement. This approach has the potential to reliably identify children at risk for amblyopia.

Biracial and Monoracial Infant Own-Race Face Perception: An Eye Tracking Study

PubMed Central

Gaither, Sarah E.; Pauker, Kristin; Johnson, Scott P.

2012-01-01

We know early experience plays a crucial role in the development of face processing, but we know little about how infants learn to distinguish faces from different races, especially for non-Caucasian populations. Moreover, it is unknown whether differential processing of different race faces observed in typically-studied monoracial infants extends to biracial infants as well. Thus, we investigated 3-month-old Caucasian, Asian and biracial (Caucasian-Asian) infants’ ability to distinguish Caucasian and Asian faces. Infants completed two within-subject, infant-controlled habituation sequences and test trials as an eye tracker recorded looking times and scanning patterns. Examination of individual differences revealed significant positive correlations between own-race novelty preference and scanning frequency between eye and mouth regions of own-race habituation stimuli for Caucasian and Asian infants, suggesting that facility in own-race face discrimination stems from active inspection of internal facial features in these groups. Biracial infants, however, showed the opposite effect: An “own-race” novelty preference was associated with reduced scanning between eye and mouth regions of “own-race” habituation stimuli, suggesting that biracial infants use a distinct approach to processing frequently encountered faces. Future directions for investigating face processing development in biracial populations are discussed. PMID:23106731

Parents' awareness and perception of children's eye diseases in Nigeria.

PubMed

Ebeigbe, Jennifer A; Emedike, Chike Martin

Most causes of childhood blindness are treatable or preventable. Knowledge of parents' awareness and perception of eye problems is important in helping to understand parents' eye care seeking behavior. This understanding becomes necessary as early detection and intervention can be effective when done at an early age. Study was carried out in Benin City, Nigeria. Thirty-five parents aged 38-54 years with a mean age of 43(±2) years were recruited. Twenty six were females and nine males. Ten eye care practitioners aged 30-45 years with a mean age of 40 (±2) were included. Seven were males and three were females. Data was analyzed qualitatively and in percentages. Majority of parents were aware of common eye problems: Blurry vision (85.7%), measles in eye (48.5%), cataract (74.3%), conjunctivitis (48.5%), itching and redness (74.3%), crossed eyes (34.3%), strabismus (57.1%), short sightedness (48.5%) and stye or hordeolum (57.1%). Too much carbohydrate, night reading and too much TV were some of the reasons given for bad eyesight. Self medication and use of local remedies for treatment of conjunctivitis was common practice (94.3%). Chloramphenicol eyedrop was the most common drug used for any eye problem before visiting a doctor (80.0%). Parents are aware of common eye diseases in children but have wrong perception of their causes. Programs to increase public awareness of causes of eye problems and harmful effects of self medication are advocated for to expose inherent dangers. Copyright © 2016 Spanish General Council of Optometry. Published by Elsevier España, S.L.U. All rights reserved.

Characteristics of Incident Geographic Atrophy in the Complications of Age-related Macular Degeneration Prevention Trial

PubMed Central

Brader, Hilary Smolen; Ying, Gui-shuang; Martin, E. Revell; Maguire, Maureen G.

2013-01-01

Objective To characterize the size, location, conformation, and features of incident geographic atrophy (GA) as detected by annual stereoscopic color photographs and fluorescein angiograms (FAs). Design Retrospective cohort study within a larger clinical trial Participants Patients with bilateral large drusen who developed GA during the course of the Complications of Age-related Macular Degeneration Prevention Trial (CAPT). Methods Annual stereoscopic color photographs and FAs were reviewed from 114 CAPT patients who developed GA in the untreated eye during 5-6 years of follow-up. Geographic atrophy was defined according to the Revised GA Criteria for identifying early GA23. Color-optimized fundus photographs were viewed concurrently with the FAs during grading. Main Outcome Measures Size and distance from the fovea of individual GA lesions, number of areas of atrophy, and change in visual acuity (VA) when GA first developed in an eye. Results At presentation, the median total GA area was 0.26mm2 (0.1 Disc area). GA presented as a single lesion in 89 (78%) of eyes. The median distance from the fovea was 395μm. Twenty percent of incident GA lesions were subfoveal and an additional 18% were within 250μm of the foveal center. Development of GA was associated with a mean decrease of 7 letters from the baseline visual acuity level compared to 1 letter among matched early age-related macular degeneration (AMD) eyes without GA. GA that formed in areas previously occupied by drusenoid pigment epithelial detachments (DPED) were on average larger (0.53 vs. 0.20 mm2; p=0.0001), more central (50 vs. 500 microns from the center of the fovea; p<0.0001), and associated with significantly worse visual outcome (20/50 vs. 20/25; p=0.0003) than GA with other drusen types as precursors. Conclusions Incident geographic atrophy most often appears on color fundus photographs and fluorescein angiograms as a small, singular, parafoveal lesion, though a large minority of lesions are subfoveal or multifocal at initial detection. The characteristics of incident geographic atrophy vary with precursor drusen types. These data can facilitate design of future clinical trials of therapies for GA. PMID:23622873

Studies of Weak, ELF Electromagnetic Fields Effects on the Early Embryonic Development

DTIC Science & Technology

1988-12-29

characters: - General aspect: stage; size of the embryo; size of the head relatively to the trunk. - Head : morphology of the skull; development of...the eyes; size and morphology of the beak; size of the neck . - Trunk: morphology of the vertebral column; development of the tail; closure of thorax and...mishandled, the orientation of the embryo was not taken into account. As indicated in Fig. 7, the head -tail axis orientation of an embryo was North (N

Highly Sensitive Naked-Eye Assay for Enterovirus 71 Detection Based on Catalytic Nanoparticle Aggregation and Immunomagnetic Amplification.

PubMed

Xiong, Ling-Hong; He, Xuewen; Xia, Junjie; Ma, Hanwu; Yang, Fan; Zhang, Qian; Huang, Dana; Chen, Long; Wu, Chunli; Zhang, Xiaomin; Zhao, Zheng; Wan, Chengsong; Zhang, Renli; Cheng, Jinquan

2017-05-03

Development of sensitive, convenient, and cost-effective virus detection product is of great significance to meet the growing demand of clinical diagnosis at the early stage of virus infection. Herein, a naked-eye readout of immunoassay by means of virion bridged catalase-mediated in situ reduction of gold ions and growth of nanoparticles, has been successfully proposed for rapid visual detection of Enterovirus 71 (EV71). Through tailoring the morphologies of the produced gold nanoparticles (GNPs) varying between dispersion and aggregation, a distinguishing color changing was ready for observation. This colorimetric detection assay, by further orchestrating the efficient magnetic enrichment and the high catalytic activity of enzyme, is managed to realize highly sensitive detection of EV71 virions with the limit of detection (LOD) down to 0.65 ng/mL. Our proposed method showed a much lower LOD value than the commercial ELISA for EV71 virion detection. Comparing to the current clinical gold standard polymerase chain reaction (PCR) method, our strategy provided the same diagnostic outcomes after testing real clinical samples. Besides, this strategy has no need of complicated sample pretreatment or expensive instruments. Our presented naked-eye immunoassay method holds a promising prospect for the early detection of virus-infectious disease especially in resource-constrained settings.

An Integrative Model for the Neural Mechanism of Eye Movement Desensitization and Reprocessing (EMDR).

PubMed

Coubard, Olivier A

2016-01-01

Since the seminal report by Shapiro that bilateral stimulation induces cognitive and emotional changes, 26 years of basic and clinical research have examined the effects of Eye Movement Desensitization and Reprocessing (EMDR) in anxiety disorders, particularly in post-traumatic stress disorder (PTSD). The present article aims at better understanding EMDR neural mechanism. I first review procedural aspects of EMDR protocol and theoretical hypothesis about EMDR effects, and develop the reasons why the scientific community is still divided about EMDR. I then slide from psychology to physiology describing eye movements/emotion interaction from the physiological viewpoint, and introduce theoretical and technical tools used in movement research to re-examine EMDR neural mechanism. Using a recent physiological model for the neuropsychological architecture of motor and cognitive control, the Threshold Interval Modulation with Early Release-Rate of rIse Deviation with Early Release (TIMER-RIDER)-model, I explore how attentional control and bilateral stimulation may participate to EMDR effects. These effects may be obtained by two processes acting in parallel: (i) activity level enhancement of attentional control component; and (ii) bilateral stimulation in any sensorimotor modality, both resulting in lower inhibition enabling dysfunctional information to be processed and anxiety to be reduced. The TIMER-RIDER model offers quantitative predictions about EMDR effects for future research about its underlying physiological mechanisms.

Vancomycin-Associated Hemorrhagic Occlusive Retinal Vasculitis: Clinical Characteristics of 36 Eyes.

PubMed

Witkin, Andre J; Chang, David F; Jumper, J Michael; Charles, Steve; Eliott, Dean; Hoffman, Richard S; Mamalis, Nick; Miller, Kevin M; Wykoff, Charles C

2017-05-01

To expand understanding of presentation, diagnosis, and outcomes of hemorrhagic occlusive retinal vasculitis (HORV). Retrospective case series. Thirty-six eyes of 23 patients. The American Society of Cataract and Refractive Surgery (ASCRS) and the American Society of Retina Specialists (ASRS) formed a joint task force to define clinical characteristics of HORV and to study its prevalence, cause, treatment, and outcomes. An online registry was established on both societies' web sites. Surveys were e-mailed to members of both societies soliciting cases of suspected HORV. A literature search was performed to uncover additional cases. Historical data including intraoperative characteristics, images, treatment regimens, and visual and anatomic outcomes. Characteristic findings of HORV included unremarkable postoperative day 1 undilated examination, delayed-onset painless vision loss, mild anterior chamber and vitreous inflammation, sectoral retinal hemorrhages in areas of ischemia, and predilection for venules and peripheral involvement. Based on predetermined diagnostic criteria, 36 eyes of 23 patients were diagnosed with HORV. All eyes received intraocular vancomycin via intracameral bolus (33/36), via intravitreal injection (1/36), or through the irrigation bottle (2/36). Patients sought treatment with HORV 1 to 21 days after surgery or intravitreal injection. Visual results usually were poor: 22 of 36 eyes (61%) had 20/200 or worse visual acuity and 8 of 36 eyes (22%) had no light perception (NLP). Neovascular glaucoma developed in 20 of 36 eyes (56%). Seven eyes received additional intravitreal vancomycin after surgery; 5 of these 7 eyes had NLP visual acuity at the most recent examination. Three eyes received intravitreal corticosteroids and had final visual acuities of 20/40, 20/70, and hand movements. Hemorrhagic occlusive retinal vasculitis is a rare, potentially devastating condition that can develop after cataract surgery or intraocular injection. All cases in this series were associated with intraocular vancomycin. Disease course and findings suggest that HORV is caused by a delayed hypersensitivity reaction to vancomycin. Early treatment with corticosteroids likely is beneficial. Subsequently, anti-vascular endothelial growth factor injections and panretinal photocoagulation are important to prevent neovascular glaucoma, a common complication. Avoidance of additional intravitreal vancomycin is recommended if HORV is suspected. Published by Elsevier Inc.

Impaired Attention to the Eyes of Attachment Figures and the Developmental Origins of Psychopathy

ERIC Educational Resources Information Center

Dadds, Mark R.; Jambrak, Jasmin; Pasalich, Dave; Hawes, David J.; Brennan, John

2011-01-01

Background: A pervasive failure to attend and respond to emotionally salient stimuli is a core feature of psychopathy. We hypothesise that this begins early in life and is expressed most importantly as a failure to attend to core emotional features (viz., the eyes) of attachment figures. The current study tested whether impaired eye contact is a…

In vivo laser scanning confocal microscopy of the cornea in patients with silicone oil tamponade after vitreoretinal surgery.

PubMed

Le, Qihua; Wang, Xin; Lv, Jiahua; Sun, Xinghuai; Xu, Jianjiang

2012-08-01

To evaluate the morphological changes in the cornea by in vivo laser scanning confocal microscopy (LSCM) in a large case series with silicone oil endotamponade after vitreoretinal surgery and to explore the value of LSCM in the early detection of silicone keratopathy (SK). Ninety-nine patients (99 eyes) with silicone oil endotamponade after vitreoretinal surgery were included in the current study. Slit-lamp examination and measurement of intraocular pressure (IOP) were performed first. Then the central corneas of the subjects' eyes were examined by in vivo LSCM. The analysis of images of each corneal layer was performed and the endothelial cellular density (ECD), endothelial cellular area (ECA), coefficient of variation of cell size (CoV), and percentage of hexagonal cells (PHC) were measured. Moreover, the total size of stromal deposits was measured, and the correlation between the size of deposits and the parameters of endothelial cells was analyzed. Clinically recognizable abnormalities involving the cornea were identified in only 12 eyes (12.1%) under slit-lamp biomicroscopy, whereas in vivo LSCM revealed morphological abnormalities in 40 eyes (40.4%). The manifestations of endothelial lesions varied from decreased cellular density, increased polymegathism and pleomorphism to hyperreflective silicone oil membrane or droplets adhering to the endothelium. Moreover, hyperreflective deposits with various shapes could be identified in both posterior and anterior stroma, along with the infiltration of Langerhans cells beneath the epithelium. The average ECD and PHC of eyes with corneal abnormalities were significantly lower than those of normal corneas, whereas the average ECA and CoV were significantly larger (all Ps < 0.001). The patients with corneal abnormalities were significantly older than those others (P = 0.003). The rate of pseudophakic and aphakic eyes having corneal abnormalities was significantly higher than that of phakic eyes (P = 0.045). Interestingly, the total size of stromal deposits had a significant negative correlation with ECD and PHC but a significant positive correlation with ECA and CoV (all Ps < 0.001). Further correlation analysis performed in groups divided according to the lens status showed similar results and even stronger correlations in aphakic and pseudophakic eyes, whereas no statistically significant correlations were found in phakic eyes. In vivo LSCM was a useful tool in the early detection of corneal abnormalities caused by silicone oil injection, including varying corneal endothelium lesions and stromal abnormalities. Pseudophakic or aphakic eyes, as well as those of older patients, should receive more attention because they are more inclined to develop silicone keratopathy.

Comparing the Rates of Retinal Nerve Fiber Layer and Ganglion Cell-Inner Plexiform Layer Loss in Healthy Eyes and in Glaucoma Eyes.

PubMed

Hammel, Naama; Belghith, Akram; Weinreb, Robert N; Medeiros, Felipe A; Mendoza, Nadia; Zangwill, Linda M

2017-06-01

To compare the rates of circumpapillary retinal nerve fiber layer (RNFL) and macular retinal ganglion cell-inner plexiform layer (GCIPL) change over time in healthy and glaucoma eyes. Cohort study. The rates of circumpapillary RNFL and macular GCIPL loss in 28 healthy subjects and 97 glaucoma subjects from the Diagnostic Innovations in Glaucoma Study (DIGS) were compared using mixed-effects models. The median follow-up time and number of visits were 1.7 years and 6 visits and 3.2 years and 7 visits for healthy and glaucoma eyes, respectively. Significant rates of loss of both global circumpapillary RNFL and average macular GCIPL thickness were detectable in early and moderate glaucoma eyes; in severe glaucoma eyes, rates of average macular GCIPL loss were significant, but rates of global circumpapillary RNFL loss were not. In glaucoma eyes, mean rates of global circumpapillary RNFL thickness change (-0.98 μm/year [95% confidence interval (CI), -1.20 to -0.76]) and normalized global circumpapillary RNFL change (-1.7%/year [95% CI, -2.1 to -1.3]) were significantly faster than average macular GCIPL change (-0.57 μm/year [(95% CI, -0.73 to -0.41]) and normalized macular GCIPL change (-1.3%/year [95% CI, -1.7 to -0.9]). The rates of global and inferior RNFL change were weakly correlated with global and inferior macular GCIPL change (r ranges from 0.16 to 0.23, all P < .05). In this cohort, the rate of circumpapillary RNFL thickness change was faster than macular GCIPL change for glaucoma eyes. Global circumpapillary RNFL thickness loss was detectable in early and moderate glaucoma, and average macular GCIPL thickness loss was detectable in early, moderate, and severe glaucoma, suggesting that structural changes can be detected in severe glaucoma. Copyright © 2017 Elsevier Inc. All rights reserved.

Diagnosis, disease notification, and management of rapid eye movement (REM) sleep behavior disorder.

PubMed

Shimohata, Takayoshi; Inoue, Yuichi; Hirata, Koichi

2017-02-25

Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by dream enactment behavior during REM sleep. It has been demonstrated that patients with idiopathic RBD are at a significantly increased risk of developing one of the α-synucleinopathies later in life, and this is called "phenoconversion". Although some physicians argue against disclosing information that could cause patients psychological stress, the patients also have a "right to know" about their own disease. Therefore, determining when and how to disclose this information, in addition to appropriate follow-up, is important. Clonazepam is the first choice of treatment for RBD associated with α-synucleinopathies. Since RBD is one of the premotor symptoms of α-synucleinopathies, and enables its early diagnosis, a combination of RBD and other examinations may contribute to the realization of a disease-modifying therapy. It is hoped that the early establishment of biomarkers could help predict the phenoconversion from RBD to α-synucleinopathies.

Ophthalmic Vascular Events after Primary Unilateral Intra-arterial Chemotherapy for Retinoblastoma in Early and Recent Eras.

PubMed

Dalvin, Lauren A; Ancona-Lezama, David; Lucio-Alvarez, J Antonio; Masoomian, Babak; Jabbour, Pascal; Shields, Carol L

2018-06-16

To assess risk factors for ophthalmic vascular events after intra-arterial chemotherapy (IAC) for retinoblastoma. Retrospective cohort study. Patients who received unilateral IAC as primary treatment for retinoblastoma from January 1, 2009, to November 30, 2017, at a single center. Records were reviewed for patient demographics, tumor features, IAC parameters, and treatment-related vascular events in the early IAC era (2009-2011) compared with the recent era (2012-2017) using the t test and Fisher exact test. Change in event rates over time was assessed using Poisson regression analysis, with Spearman's rho used to test correlation. Rate of IAC-induced ophthalmic vascular events. There were 243 chemotherapy infusions in 76 eyes of 76 patients, divided into early (22 eyes, 57 infusions) and recent (54 eyes, 186 infusions) eras. Intra-arterial chemotherapy consisted of melphalan (243 infusions), topotecan (124 infusions), and carboplatin (9 infusions). A comparison (early vs. recent era) revealed fewer mean number of infusions (2.6 vs. 3.4, P = 0.02) with similar mean patient age and presenting tumor features. Event rates decreased over time (P < 0.01), with fewer ophthalmic vascular events (early era vs. recent era) in the recent era (59% vs. 9% per eye, 23% vs. 3% per infusion, P < 0.01), including peripheral retinal nonperfusion (5% vs. 2% per eye, P = 0.50), vitreous hemorrhage (9% vs. 2%, P = 0.20), subretinal hemorrhage (0% vs. 2%, P = 0.99), branch retinal vein occlusion (5% vs. 0%, P = 0.29), choroidal ischemia (14% vs. 4%, P = 0.14), and ophthalmic artery spasm/occlusion (27% vs. 0%, P < 0.01). Events did not correlate to patient age (P = 0.75), tumor diameter (P = 0.32), tumor thickness (P = 0.59), or cumulative dosage of melphalan (P = 0.13) or topotecan (P = 0.59). There were no IAC-induced vascular events in 72 infusions of 21 consecutively treated eyes in 2016 to 2017. Ophthalmic vascular events after IAC have decreased from the early era (2009-2011) through the current era (2012-2017) at this center. Experience performing this highly specialized procedure could be an important factor predicting IAC-related vascular events. Copyright © 2018 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Drosophila Protein Kinase CK2: Genetics, Regulatory Complexity and Emerging Roles during Development

PubMed Central

Bandyopadhyay, Mohna; Arbet, Scott; Bishop, Clifton P.; Bidwai, Ashok P.

2016-01-01

CK2 is a Ser/Thr protein kinase that is highly conserved amongst all eukaryotes. It is a well-known oncogenic kinase that regulates vital cell autonomous functions and animal development. Genetic studies in the fruit fly Drosophila are providing unique insights into the roles of CK2 in cell signaling, embryogenesis, organogenesis, neurogenesis, and the circadian clock, and are revealing hitherto unknown complexities in CK2 functions and regulation. Here, we review Drosophila CK2 with respect to its structure, subunit diversity, potential mechanisms of regulation, developmental abnormalities linked to mutations in the gene encoding CK2 subunits, and emerging roles in multiple aspects of eye development. We examine the Drosophila CK2 “interaction map” and the eye-specific “transcriptome” databases, which raise the prospect that this protein kinase has many additional targets in the developing eye. We discuss the possibility that CK2 functions during early retinal neurogenesis in Drosophila and mammals bear greater similarity than has been recognized, and that this conservation may extend to other developmental programs. Together, these studies underscore the immense power of the Drosophila model organism to provide new insights and avenues to further investigate developmentally relevant targets of this protein kinase. PMID:28036067

Fetal Eye Movements on Magnetic Resonance Imaging

PubMed Central

Woitek, Ramona; Kasprian, Gregor; Lindner, Christian; Stuhr, Fritz; Weber, Michael; Schöpf, Veronika; Brugger, Peter C.; Asenbaum, Ulrika; Furtner, Julia; Bettelheim, Dieter; Seidl, Rainer; Prayer, Daniela

2013-01-01

Objectives Eye movements are the physical expression of upper fetal brainstem function. Our aim was to identify and differentiate specific types of fetal eye movement patterns using dynamic MRI sequences. Their occurrence as well as the presence of conjugated eyeball motion and consistently parallel eyeball position was systematically analyzed. Methods Dynamic SSFP sequences were acquired in 72 singleton fetuses (17–40 GW, three age groups [17–23 GW, 24–32 GW, 33–40 GW]). Fetal eye movements were evaluated according to a modified classification originally published by Birnholz (1981): Type 0: no eye movements; Type I: single transient deviations; Type Ia: fast deviation, slower reposition; Type Ib: fast deviation, fast reposition; Type II: single prolonged eye movements; Type III: complex sequences; and Type IV: nystagmoid. Results In 95.8% of fetuses, the evaluation of eye movements was possible using MRI, with a mean acquisition time of 70 seconds. Due to head motion, 4.2% of the fetuses and 20.1% of all dynamic SSFP sequences were excluded. Eye movements were observed in 45 fetuses (65.2%). Significant differences between the age groups were found for Type I (p = 0.03), Type Ia (p = 0.031), and Type IV eye movements (p = 0.033). Consistently parallel bulbs were found in 27.3–45%. Conclusions In human fetuses, different eye movement patterns can be identified and described by MRI in utero. In addition to the originally classified eye movement patterns, a novel subtype has been observed, which apparently characterizes an important step in fetal brainstem development. We evaluated, for the first time, eyeball position in fetuses. Ultimately, the assessment of fetal eye movements by MRI yields the potential to identify early signs of brainstem dysfunction, as encountered in brain malformations such as Chiari II or molar tooth malformations. PMID:24194885

Robust Eye Center Localization through Face Alignment and Invariant Isocentric Patterns

PubMed Central

Teng, Dongdong; Chen, Dihu; Tan, Hongzhou

2015-01-01

The localization of eye centers is a very useful cue for numerous applications like face recognition, facial expression recognition, and the early screening of neurological pathologies. Several methods relying on available light for accurate eye-center localization have been exploited. However, despite the considerable improvements that eye-center localization systems have undergone in recent years, only few of these developments deal with the challenges posed by the profile (non-frontal face). In this paper, we first use the explicit shape regression method to obtain the rough location of the eye centers. Because this method extracts global information from the human face, it is robust against any changes in the eye region. We exploit this robustness and utilize it as a constraint. To locate the eye centers accurately, we employ isophote curvature features, the accuracy of which has been demonstrated in a previous study. By applying these features, we obtain a series of eye-center locations which are candidates for the actual position of the eye-center. Among these locations, the estimated locations which minimize the reconstruction error between the two methods mentioned above are taken as the closest approximation for the eye centers locations. Therefore, we combine explicit shape regression and isophote curvature feature analysis to achieve robustness and accuracy, respectively. In practical experiments, we use BioID and FERET datasets to test our approach to obtaining an accurate eye-center location while retaining robustness against changes in scale and pose. In addition, we apply our method to non-frontal faces to test its robustness and accuracy, which are essential in gaze estimation but have seldom been mentioned in previous works. Through extensive experimentation, we show that the proposed method can achieve a significant improvement in accuracy and robustness over state-of-the-art techniques, with our method ranking second in terms of accuracy. According to our implementation on a PC with a Xeon 2.5Ghz CPU, the frame rate of the eye tracking process can achieve 38 Hz. PMID:26426929

Inter-Creative Course Model Proposal: Teaching- Learning Design in Secondary Schools of TRNC

ERIC Educational Resources Information Center

Ulas-Dagli, Ugur; Pasaoglulari-Sahin, Nil; Güley, Kamil

2013-01-01

Problem Statement: Design is an indispensable part of the human being. It enters one's life on the very first day that the eyes open. Design awareness is developed at an early age. With a proper education, even in the preschool years, design is experienced within one's close environment. Purpose of the Study: This study aims to determine the…

Shunning the Bird's Eye View: General Science in the Schools of Ontario and Quebec

ERIC Educational Resources Information Center

Hoffman, Michelle

2013-01-01

This paper considers the adoption of general science courses in two Canadian provinces, Ontario and Quebec, during the 1930s. In Ontario, a few science teachers had followed the early general science movements in the United States and Britain with interest. During the 1930s, several developments made the cross-disciplinary, applied thrust of…

The Harvard angiogenesis story.

PubMed

Miller, Joan W

2014-01-01

I shall discuss the work of researchers at Harvard Medical School who came together in the early 1990s. Scattered across various Harvard-affiliated hospitals and research centers, these individuals were unified by their interest in ocular neovascularization. Together and separately, they investigated models of ocular neovascularization, exploring tumor angiogenesis in eye development and disease. Copyright © 2014 The Author. Published by Elsevier Inc. All rights reserved.

Objects predict fixations better than early saliency.

PubMed

Einhäuser, Wolfgang; Spain, Merrielle; Perona, Pietro

2008-11-20

Humans move their eyes while looking at scenes and pictures. Eye movements correlate with shifts in attention and are thought to be a consequence of optimal resource allocation for high-level tasks such as visual recognition. Models of attention, such as "saliency maps," are often built on the assumption that "early" features (color, contrast, orientation, motion, and so forth) drive attention directly. We explore an alternative hypothesis: Observers attend to "interesting" objects. To test this hypothesis, we measure the eye position of human observers while they inspect photographs of common natural scenes. Our observers perform different tasks: artistic evaluation, analysis of content, and search. Immediately after each presentation, our observers are asked to name objects they saw. Weighted with recall frequency, these objects predict fixations in individual images better than early saliency, irrespective of task. Also, saliency combined with object positions predicts which objects are frequently named. This suggests that early saliency has only an indirect effect on attention, acting through recognized objects. Consequently, rather than treating attention as mere preprocessing step for object recognition, models of both need to be integrated.

Investigation of changes in fractal dimension from layered retinal structures of healthy and diabetic eyes with optical coherence tomography

NASA Astrophysics Data System (ADS)

Gao, Wei; Zakharov, Valery P.; Myakinin, Oleg O.; Bratchenko, Ivan A.; Artemyev, Dmitry N.; Kornilin, Dmitry V.

2015-07-01

Optical coherence tomography (OCT) is usually employed for the measurement of retinal thickness characterizing the structural changes of tissue. However, fractal dimension (FD) could also character the structural changes of tissue. Therefore, fractal dimension changes may provide further information regarding cellular layers and early damage in ocular diseases. We investigated the possibility of OCT in detecting changes in fractal dimension from layered retinal structures. OCT images were obtained from diabetic patients without retinopathy (DM, n = 38 eyes) or mild diabetic retinopathy (MDR, n = 43 eyes) and normal healthy subjects (Controls, n = 74 eyes). Fractal dimension was calculated using the differentiate box counting methodology. We evaluated the usefulness of quantifying fractal dimension of layered structures in the detection of retinal damage. Generalized estimating equations considering within-subject intereye relations were used to test for differences between the groups. A modified p value of <0.001 was considered statistically significant. Receiver operating characteristic (ROC) curves were constructed to describe the ability of fractal dimension to discriminate between the eyes of DM, MDR and healthy eyes. Significant decreases of fractal dimension were observed in all layers in the MDR eyes compared with controls except in the inner nuclear layer (INL). Significant decreases of fractal dimension were also observed in all layers in the MDR eyes compared with DM eyes. The highest area under receiver operating characteristic curve (AUROC) values estimated for fractal dimension were observed for the outer plexiform layer (OPL) and outer segment photoreceptors (OS) when comparing MDR eyes with controls. The highest AUROC value estimated for fractal dimension were also observed for the retinal nerve fiber layer (RNFL) and OS when comparing MDR eyes with DM eyes. Our results suggest that fractal dimension of the intraretinal layers may provide useful information to differentiate pathological from healthy eyes. Further research is warranted to determine how this approach may be used to improve diagnosis of early retinal neurodegeneration.

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

PubMed

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

2012-09-01

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

Ahmed Glaucoma Valve Implantation in Vitrectomized Eyes.

PubMed

Erçalık, Nimet Yeşim; İmamoğlu, Serhat

2018-01-01

To evaluate the outcomes of Ahmed glaucoma valve (AGV) implantation in vitrectomized eyes. The medical records of 13 eyes that developed glaucoma due to emulsified silicon oil or neovascularization following pars plana vitrectomy and underwent AGV implantation were retrospectively reviewed. The main outcome measures were intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of antiglaucoma medications, and postoperative complications. Surgical success was defined as last IOP ≤21 mmHg or ≥6 mmHg and without loss of light perception. The mean follow-up duration was 11.7 ± 5.5 (range, 6-23) months. The mean IOP before the AGV implantation was 37.9 ± 6.7 mmHg with an average of 3.5 ± 1.2 drugs. At the final visit, the mean IOP was 15.9 ± 4.6 mmHg ( p =0.001) and the mean number of glaucoma medications decreased to 2.3 ± 1.3 ( p =0.021). At the last visit, 11 eyes (84.4%) had stable or improved VA and one eye (7.7%) had a final VA of no light perception. Surgical success was achieved in 11 of the 13 eyes (84.4%). Postoperative complications were bleb encapsulation (69.2%), early hypotony (38.5%), hyphema (23.1%), decompression retinopathy (23.1%), choroidal detachment (15.4%), intraocular hemorrhage (7.7%), and late endophthalmitis (7.7%). One eye (7.7%) was enucleated because of late endophthalmitis. Despite complications necessitating medical and surgical interventions, vitrectomized eyes were effectively managed with AGV implantation.

Air Bubble-Induced High Intraocular Pressure After Descemet Membrane Endothelial Keratoplasty.

PubMed

Röck, Daniel; Bartz-Schmidt, Karl Ulrich; Röck, Tobias; Yoeruek, Efdal

2016-08-01

To investigate the incidence and risk factors of pupillary block caused by an air bubble in the anterior chamber in the early postoperative period after Descemet membrane endothelial keratoplasty (DMEK). A retrospective review was conducted in 306 eyes that underwent DMEK from September 2009 through October 2014 at the Tübingen Eye Hospital. Intraocular pressure (IOP) elevation was defined as a spike above 30 mm Hg. In the first 190 eyes, an intraoperative peripheral iridectomy was performed at the 12-o'clock position and in the other 116 eyes at the 6-o'clock position. If possible, reasons for IOP elevation were identified. For all eyes, preoperative and postoperative slit-lamp examinations and IOP measurements were performed. Overall, 30 eyes (9.8%) showed a postoperative IOP elevation within the first postoperative day. The incidence of IOP elevation was 13.9% (5/36) in the triple DMEK group, and 2 of 5 phakic eyes (40%) developed an air bubble-induced IOP elevation. All eyes presented with a de novo IOP elevation, associated in 25 patients with pupillary block from air anterior to iris and in 5 patients with angle closure from air migration posterior to the iris. All of them had an iridectomy at the 12-o'clock position. A postoperative pupillary block with IOP elevation caused by the residual intraoperative air bubble may be an important complication that could be avoided by close and frequent observations, especially in the first postoperative hours and by an inferior peripheral iridectomy and an air bubble with a volume of ≤80% of the anterior chamber.

Refractive Amblyopia among children in Ibadan: the need for amblyopia screening programmes.

PubMed

Olusanya, B A; Ugalahi, M O; Okoli, C E; Baiyeroju, A M

2015-09-01

The prevalence and burden of amblyopia in developing countries is probably underestimated, and little is known about the pattern of amblyopia in West Africa. To determine the relative frequency and types of amblyopia among children with refractive errors seen in the eye clinic of a tertiary hospital over a 2 year period. A cross-sectional study conducted at the eye clinic of the University College Hospital, Ibadan, Nigeria between January 2012 and December 2013. Case notes of children with refractive errors seen during this period were retrieved and information including socio-demographic data, presenting visual acuity and visual acuity with correction were recorded. Amblyopia was defined as best corrected visual acuity worse than 6/9 or a difference of ≥ 2 Snellen chart lines between both eyes in the absence of any ocular pathology that could explain the visual impairment. A total of 250 eligible patients who had refractive errors were included in the study. Visual acuity was corrected to 6/9 or better in 224 (89.6%) children while 26 (10.4%) of them had amblyopia. Among the 26 children with amblyopia, 21 (80.8%) children had amblyopia in both eyes and majority (65.4%) had iso-ametropic amblyopia. Of the 47 amblyopic eyes, 36 (76.6%) eyes had moderate amblyopia while 11 (23.4%) eyes had severe amblyopia. There is a high relative frequency of amblyopia in this study and we recommend preschool eye examinations for all children to ensure early detection and management of amblyopia, thereby reducing the burden of amblyopia in our populace.

Influence of Corticosteroids and Vitamin E Deficiency on Onset and Cytopathology of Radiation-Induced Cataract

NASA Astrophysics Data System (ADS)

Junk, A. K.; Worgul, B. V.

Cataracts characteristic of those arising from radiation exposure have been reported among the astronaut and cosmonaut corps. This being the case it is critical to appreciate how radiogenic cataracts relate to those arising from other exogenous causes such as therapeutics, which may, one day, have to be administered on an extended mission. Because they produce precisely the same clinical picture, corticosteroids are examples of a class of drugs that potentially can exacerbate damage to the lens from radiation. On the other hand, Vitamin E, a free radical scavenger, has been shown to ameliorate oxidative damage as caused by ionizing radiation and evidence is accumulating that it may constitute protection from radiogenic damage. An experimental study was conducted to understand if corticosteroids with and in the absence of Vitamin E deficiency modulate the onset of cataract induced by ionizing radiation. The right eyes of 72 28-day-old Brown-Norway rats were irradiated with 6 Gy of 240 kV X-rays, the shielded left eyes served as controls. Half of the animals were maintained on a Vitamin E free diet after irradiation, the others were kept on regular chow. In each nutritional group 18 rats additionally received dexamethasone. The initial daily dose of 10 mg/kg body weight injected subcutaneously was reduced to 0.5 mg/kg over the course of 6 months. Cataract onset and development were followed by weekly slit-lamp exam. After 6 month the lenses were harvested for microscopic analyses. Irradiated eyes in all treatment subgroups showed early cataract onset [5 wks versus 11 wks in controls (p<0.0001)]. Corticosteroids accounted for accelerated cataract development in both irradiated (p<0.0005) and non-irradiated eyes (p<0.0001) relative to respective control eyes. Vitamin E deficiency did not affect cataract incidence in combination with radiation or steroids alone. Unexpectedly, when compared to irradiated controls, cataract development was inhibited in the group that received radiation, dexamethasone and the Vitamin E free diet (p<0.0005). Radiation, at the applied dose, was the predominant risk factor for early cataract onset. However, corticosteroids accelerate cataract formation. The surprising protective influence of Vitamin E deficiency may be the result of a stathmokinetic effect on mitosis - a possibility that is supported by lens epithelial histopathology in the regions of cell mitosis and differentiation.

Influence of corticosteroids and vitamin E deficiency on onset of radiation-induced cataract

NASA Astrophysics Data System (ADS)

Junk, A. K.; Worgul, B. W.

Cataracts characteristic of those arising from radiation exposure have been reported among the astronaut and cosmonaut corps. This being the case it is critical to appreciate how radiogenic cataracts relate to those arising from other exogenous causes such as therapeutics, which may, one day, have to be administered on an extended mission. Because they produce precisely the same clinical picture, corticosteroids are examples of a class of drugs that potentially can exacerbate damage to the lens from radiation. On the other hand, Vitamin E, a free radical scavenger, has been shown to ameliorate oxidative damage as caused by ionizing radiation and evidence is accumulating that it may constitute protection from radiogenic damage. An experimental study was conducted to understand if corticosteroids with, and in the absence of Vitamin E deficiency modulate the onset of cataract induced by ionizing radiation. The right eyes of seventy-two 28-day-old Brown-Norway rats were irradiated with 6 Gy of 240 kV X-rays, the shielded left eyes served as controls. Half of the animals were maintained on a Vitamin E free diet after irradiation, the others were kept on standard chow. Fifty per cent of the animals in each nutritional group received dexamethasone. The initial daily dose of 10 mg/kg body weight injected subcutaneously was reduced to 0.5 mg/kg over the course of six months. Cataract onset and development were followed by weekly slit-lamp exam. After six month the lenses were harvested for microscopic analyses. Irradiated eyes in all treatment subgroups showed early cataract onset [5 wks vs. 11 wks in controls ( p < 0.0001)]. Corticosteroids accounted for accelerated cataract development in both irradiated ( p < 0.0005) and non-irradiated eyes ( p < 0.0001) relative to respective control eyes. Vitamin E deficiency did not affect cataract incidence in combination with radiation or steroids alone. Unexpectedly, when compared to irradiated controls, cataract development was inhibited in the group that received radiation, dexamethasone and the Vitamin E free diet ( p < 0.0005). Radiation, at the applied dose, was the predominant risk factor for early cataract onset. However, corticosteroids accelerate cataract formation. The surprising protective influence of Vitamin E deficiency may be the result of a stathmokinetic effect on mitosis - a possibility that is supported by lens epithelial histopathology in the regions of cell mitosis and differentiation.

Descemet membrane endothelial keratoplasty (DMEK) early stage graft failure in eyes with preexisting glaucoma.

PubMed

Treder, Maximilian; Alnawaiseh, Maged; Eter, Nicole

2017-07-01

To evaluate the effect of a preexisting glaucoma on the early postoperative outcome of a descemet membrane endothelial keratoplasty (DMEK). All patients who underwent DMEK surgery at the Department of Ophthalmology of the University of Muenster with a follow-up of at least 3 months (90d) were included in this study. The best corrected distance visual acuity (BCDVA), the intraocular pressure (IOD), the rate of re-keratoplasty and the rebubbling rate were inter alia recorded. The results of patients with (group 1) and without a preexisting glaucoma (group 2) were compared. 74 eyes of 59 patients with a mean follow-up of 152 ± 70 days were included. 65 eyes were in group 1 and 9 eyes in group 2. The BCDVA significantly improved in both groups after surgery (p < 0.03). The Re-keratoplasty rate (p = 0.172), the number of rebubblings per patient (p = 0.571) and the rebubbling rate (p = 0.939) were not significantly different in patients without glaucoma compared to patients with a preexisting glaucoma. In the early stage outcome of DMEK no significant impact of a preexisting glaucoma was found.

Anticipatory eye movements and long-term memory in early infancy.

PubMed

Wong-Kee-You, Audrey M B; Adler, Scott A

2016-11-01

Advances in our understanding of long-term memory in early infancy have been made possible by studies that have used the Rovee-Collier's mobile conjugate reinforcement paradigm and its variants. One function that has been attributed to long-term memory is the formation of expectations (Rovee-Collier & Hayne, 1987); consequently, a long-term memory representation should be established during expectation formation. To examine this prediction and potentially open the door on a new paradigm for exploring infants' long-term memory, using the Visual Expectation Paradigm (Haith, Hazan, & Goodman, 1988), 3-month-old infants were trained to form an expectation for predictable color and spatial information of picture events and emit anticipatory eye movements to those events. One day later, infants' anticipatory eye movements decreased in number relative to the end of training when the predictable colors were changed but not when the spatial location of the predictable color events was changed. These findings confirm that information encoded during expectation formation are stored in long-term memory, as hypothesized by Rovee-Collier and colleagues. Further, this research suggests that eye movements are potentially viable measures of long-term memory in infancy, providing confirmatory evidence for early mnemonic processes. © 2016 Wiley Periodicals, Inc.

Occlusive ligature and standardized fenestration of a Baerveldt tube with and without antimetabolites for early postoperative intraocular pressure control.

PubMed

Trible, J R; Brown, D B

1998-12-01

To determine the effectiveness of a surgical modification for a nonvalved aqueous tube shunt in controlling intraocular pressure (IOP) in the early postoperative period. The effect of antimetabolite use on IOP also was studied. A retrospective study of consecutive patients who underwent modified Baerveldt 350-mm2 implant with varied, nonrandomized, exposure to antimetabolites. Fifty-one eyes of 46 patients with uncontrolled glaucoma were examined. Identical surgical modification of a Baerveldt 350-mm2 tube was performed in all cases and consisted of placement of an occlusive 7-0 polyglactin suture just anterior to the plate followed by a through-and-through penetration of the tube just anterior to the occlusive ligature with a standardized 15 degrees blade. Seventeen eyes were not exposed to antimetabolite, while 2 groups of 17 eyes had 3 minutes' episcleral exposure to either 5-fluorouracil 50 mg/ml or mitomycin C 0.4 mg/ml at the location corresponding to the fenestration. The Tenon's layer and conjunctiva were not exposed because of concerns regarding conjunctival erosion over the device. Intraocular pressure and number of antiglaucoma medications required were analyzed. For the group, mean IOP before surgery and on postoperative days 1, 4, 10, 21, 42, 63, 84, and 112 was (in millimeters of mercury) 34.6, 20.1, 17.0, 17.2, 22.0, 17.3, 18.7, 17.4, and 15.6, respectively. There was an elevation of IOP at day 21 relative to fibrotic blockage of the fenestration before suture autolysis. This was temporized with antiglaucoma medication until suture autolysis occurred or treated with laser suture lysis (8 eyes). On day 1, hypotony occurred in 3 (6%) eyes whereas IOP greater than 30 mmHg was observed in 13 (26%) eyes. By day 10, the frequency had decreased to one (2.1 %) eye and three (6.4%) eyes, respectively. The use of antimetabolites did not result in lower IOP or less medication needed for any group at any interval (analysis of variance). This modification of a nonvalved glaucoma tube shunt device provides adequate IOP control in the early postoperative period with a low rate of hypotony and surgical complications. If elevation of IOP occurs before suture autolysis, it generally is well controlled by antiglaucoma medications or laser suture lysis. Antimetabolite exposure did not influence early postoperative IOP in this study.

Early immune responses are independent of RGC dysfunction in glaucoma with complement component C3 being protective.

PubMed

Harder, Jeffrey M; Braine, Catherine E; Williams, Pete A; Zhu, Xianjun; MacNicoll, Katharine H; Sousa, Gregory L; Buchanan, Rebecca A; Smith, Richard S; Libby, Richard T; Howell, Gareth R; John, Simon W M

2017-05-09

Various immune response pathways are altered during early, predegenerative stages of glaucoma; however, whether the early immune responses occur secondarily to or independently of neuronal dysfunction is unclear. To investigate this relationship, we used the Wld s allele, which protects from axon dysfunction. We demonstrate that DBA/2J .Wld s mice develop high intraocular pressure (IOP) but are protected from retinal ganglion cell (RGC) dysfunction and neuroglial changes that otherwise occur early in DBA/2J glaucoma. Despite this, immune pathways are still altered in DBA/2J .Wld s mice. This suggests that immune changes are not secondary to RGC dysfunction or altered neuroglial interactions, but may be directly induced by the increased strain imposed by high IOP. One early immune response following IOP elevation is up-regulation of complement C3 in astrocytes of DBA/2J and DBA/2J. Wld s mice. Unexpectedly, because the disruption of other complement components, such as C1Q, is protective in glaucoma, C3 deficiency significantly increased the number of DBA/2J eyes with nerve damage and RGC loss at an early time point after IOP elevation. Transcriptional profiling of C3-deficient cultured astrocytes implicated EGFR signaling as a hub in C3-dependent responses. Treatment with AG1478, an EGFR inhibitor, also significantly increased the number of DBA/2J eyes with glaucoma at the same early time point. These findings suggest that C3 protects from early glaucomatous damage, a process that may involve EGFR signaling and other immune responses in the optic nerve head. Therefore, therapies that target specific components of the complement cascade, rather than global inhibition, may be more applicable for treating human glaucoma.

Early immune responses are independent of RGC dysfunction in glaucoma with complement component C3 being protective

PubMed Central

Harder, Jeffrey M.; Braine, Catherine E.; Williams, Pete A.; Zhu, Xianjun; MacNicoll, Katharine H.; Sousa, Gregory L.; Buchanan, Rebecca A.; Smith, Richard S.; Howell, Gareth R.; John, Simon W. M.

2017-01-01

Various immune response pathways are altered during early, predegenerative stages of glaucoma; however, whether the early immune responses occur secondarily to or independently of neuronal dysfunction is unclear. To investigate this relationship, we used the Wlds allele, which protects from axon dysfunction. We demonstrate that DBA/2J.Wlds mice develop high intraocular pressure (IOP) but are protected from retinal ganglion cell (RGC) dysfunction and neuroglial changes that otherwise occur early in DBA/2J glaucoma. Despite this, immune pathways are still altered in DBA/2J.Wlds mice. This suggests that immune changes are not secondary to RGC dysfunction or altered neuroglial interactions, but may be directly induced by the increased strain imposed by high IOP. One early immune response following IOP elevation is up-regulation of complement C3 in astrocytes of DBA/2J and DBA/2J.Wlds mice. Unexpectedly, because the disruption of other complement components, such as C1Q, is protective in glaucoma, C3 deficiency significantly increased the number of DBA/2J eyes with nerve damage and RGC loss at an early time point after IOP elevation. Transcriptional profiling of C3-deficient cultured astrocytes implicated EGFR signaling as a hub in C3-dependent responses. Treatment with AG1478, an EGFR inhibitor, also significantly increased the number of DBA/2J eyes with glaucoma at the same early time point. These findings suggest that C3 protects from early glaucomatous damage, a process that may involve EGFR signaling and other immune responses in the optic nerve head. Therefore, therapies that target specific components of the complement cascade, rather than global inhibition, may be more applicable for treating human glaucoma. PMID:28446616

Inter-eye Asymmetry of Optical Coherence Tomography Angiography Vessel Density in Bilateral Glaucoma, Glaucoma Suspect, and Healthy Eyes.

PubMed

Hou, Huiyuan; Moghimi, Sasan; Zangwill, Linda M; Shoji, Takuhei; Ghahari, Elham; Manalastas, Patricia Isabel C; Penteado, Rafaella C; Weinreb, Robert N

2018-03-23

To investigate inter-eye retinal vessel density asymmetry in healthy, glaucoma suspect, and mild to moderate glaucoma subjects, and its potential utility for early detection of glaucomatous damage. Cross-sectional study. 153 subjects including 55 healthy, 32 glaucoma suspect, and 66 glaucoma subjects enrolled in the Diagnostic Innovations in Glaucoma Study(DIGS). Vessel density was obtained from optical coherence tomography angiography (OCT-A) macular and optic nerve head scans. Thickness of peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell complex (mGCC) was measured with spectral-domain optical coherence tomography (SD-OCT) scans. Inter-eye asymmetry was calculated by taking the absolute value of difference in vessel density and thickness between the right and left eyes. Inter-eye retinal vessel density asymmetry parameters were significantly different among the three groups. Glaucoma suspects had significantly higher peripapillary and macular inter-eye vessel density asymmetries compared to healthy groups in univariate (1.1% vs. 2.0%, P=0.014 and 1.2% vs. 2.5%, P=0.027, respectively) and multivariate analyses (P=0.007 and 0.038, respectively). No significant differences in asymmetry of thickness parameters were found between glaucoma suspect and healthy groups (all P> 0.718). However significant differences in asymmetry of thickness parameters between glaucoma suspects and glaucoma patients (P<0.01) were found for all parameters. Inter-eye vessel density asymmetry can be quantified by OCT-A measurement. Glaucoma suspects have significantly greater vessel density asymmetry than healthy eyes. Longitudinal studies are needed to better characterize the relationship of vessel density asymmetry with the development and progression of glaucoma. Copyright © 2018 Elsevier Inc. All rights reserved.

Visual processing and social cognition in schizophrenia: relationships among eye movements, biological motion perception, and empathy.

PubMed

Matsumoto, Yukiko; Takahashi, Hideyuki; Murai, Toshiya; Takahashi, Hidehiko

2015-01-01

Schizophrenia patients have impairments at several levels of cognition including visual attention (eye movements), perception, and social cognition. However, it remains unclear how lower-level cognitive deficits influence higher-level cognition. To elucidate the hierarchical path linking deficient cognitions, we focused on biological motion perception, which is involved in both the early stage of visual perception (attention) and higher social cognition, and is impaired in schizophrenia. Seventeen schizophrenia patients and 18 healthy controls participated in the study. Using point-light walker stimuli, we examined eye movements during biological motion perception in schizophrenia. We assessed relationships among eye movements, biological motion perception and empathy. In the biological motion detection task, schizophrenia patients showed lower accuracy and fixated longer than healthy controls. As opposed to controls, patients exhibiting longer fixation durations and fewer numbers of fixations demonstrated higher accuracy. Additionally, in the patient group, the correlations between accuracy and affective empathy index and between eye movement index and affective empathy index were significant. The altered gaze patterns in patients indicate that top-down attention compensates for impaired bottom-up attention. Furthermore, aberrant eye movements might lead to deficits in biological motion perception and finally link to social cognitive impairments. The current findings merit further investigation for understanding the mechanism of social cognitive training and its development. Copyright © 2014 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

Rapid Simultaneous Enhancement of Visual Sensitivity and Perceived Contrast during Saccade Preparation

PubMed Central

Rolfs, Martin; Carrasco, Marisa

2012-01-01

Humans and other animals with foveate vision make saccadic eye movements to prioritize the visual analysis of behaviorally relevant information. Even before movement onset, visual processing is selectively enhanced at the target of a saccade, presumably gated by brain areas controlling eye movements. Here we assess concurrent changes in visual performance and perceived contrast before saccades, and show that saccade preparation enhances perception rapidly, altering early visual processing in a manner akin to increasing the physical contrast of the visual input. Observers compared orientation and contrast of a test stimulus, appearing briefly before a saccade, to a standard stimulus, presented previously during a fixation period. We found simultaneous progressive enhancement in both orientation discrimination performance and perceived contrast as time approached saccade onset. These effects were robust as early as 60 ms after the eye movement was cued, much faster than the voluntary deployment of covert attention (without eye movements), which takes ~300 ms. Our results link the dynamics of saccade preparation, visual performance, and subjective experience and show that upcoming eye movements alter visual processing by increasing the signal strength. PMID:23035086

Shorter spontaneous fixation durations in infants with later emerging autism

PubMed Central

Wass, Sam V.; Jones, Emily J. H.; Gliga, Teodora; Smith, Tim J.; Charman, Tony; Johnson, Mark H.; Baron-Cohen, Simon; Bedford, Rachael; Bolton, Patrick; Chandler, Susie; Davies, Kim; Fernandes, Janice; Garwood, Holly; Hudry, Kristelle; Maris, Helen; Pasco, Greg; Pickles, Andrew; Ribiero, Helena; Tucker, Leslie; Volein, Agnes

2015-01-01

Little is known about how spontaneous attentional deployment differs on a millisecond-level scale in the early development of autism spectrum disorders (ASD). We measured fine-grained eye movement patterns in 6-to 9-month-old infants at high or low familial risk (HR/LR) of ASD while they viewed static images. We observed shorter fixation durations (i.e. the time interval between saccades) in HR than LR infants. Preliminary analyses indicate that these results were replicated in a second cohort of infants. Fixation durations were shortest in those infants who went on to receive an ASD diagnosis at 36 months. While these findings demonstrate early-developing atypicality in fine-grained measures of attentional deployment early in the etiology of ASD, the specificity of these effects to ASD remains to be determined. PMID:25655672

[Hereditary cerebro-oculo-renal syndromes].

PubMed

Sessa, Galina; Hjortshøj, Tina Duelund; Egfjord, Martin

2014-02-17

Although many congenital diseases present disturbances of the central nervous system, eyes and renal function, only few of these have a defined genetic basis. The first clinical features of cerebro-oculo-renal diseases usually develop in early childhood and deterioration of kidney function and even end-stage kidney disease may occur in a young age. The syndromes should be considered in patients with retarded growth and development, central nervous system abnormalities, impaired vision or blindness and progressive renal failure.

Non-topography-guided PRK combined with CXL for the correction of refractive errors in patients with early stage keratoconus.

PubMed

Fadlallah, Ali; Dirani, Ali; Chelala, Elias; Antonios, Rafic; Cherfan, George; Jarade, Elias

2014-10-01

To evaluate the safety and clinical outcome of combined non-topography-guided photorefractive keratectomy (PRK) and corneal collagen cross-linking (CXL) for the treatment of mild refractive errors in patients with early stage keratoconus. A retrospective, nonrandomized study of patients with early stage keratoconus (stage 1 or 2) who underwent simultaneous non-topography-guided PRK and CXL. All patients had at least 2 years of follow-up. Data were collected preoperatively and postoperatively at the 6-month, 1-year, and 2-year follow-up visit after combined non-topography-guided PRK and CXL. Seventy-nine patients (140 eyes) were included in the study. Combined non-topography-guided PRK and CXL induced a significant improvement in both visual acuity and refraction. Uncorrected distance visual acuity significantly improved from 0.39 ± 0.22 logMAR before combined non-topography-guided PRK and CXL to 0.12 ± 0.14 logMAR at the last follow-up visit (P <.001) and corrected distance visual acuity remained stable (0.035 ± 0.062 logMAR preoperatively vs 0.036 ± 0.058 logMAR postoperatively, P =.79). The mean spherical equivalent decreased from -1.78 ± 1.43 to -0.42 ± 0.60 diopters (D) (P <.001), and the mean cylinder decreased from 1.47 ± 1.10 to 0.83 ± 0.55 D (P <.001). At the last follow-up visit mean keratometry flat was 43.30 ± 1.75 vs 45.62 ± 1.72 D preoperatively (P = .03) and mean keratometry steep was 44.39 ± 3.14 vs 46.53 ± 2.13 D preoperatively (P = .02). Mean central corneal thickness decreased from 501.74 ± 13.11 to 475.93 ± 12.25 µm following combined non-topography-guided PRK and CXL (P < .001). No intraoperative complications occurred. Four eyes developed mild haze that responded well to a short course of topical steroids. No eye developed infectious keratitis. Combined non-topography-guided PRK and CXL is an effective and safe option for correcting mild refractive error and improving visual acuity in patients with early stable keratoconus. Copyright 2014, SLACK Incorporated.

Effect of spectrum bias on the diagnostic accuracy of spectral-domain optical coherence tomography in glaucoma.

PubMed

Rao, Harsha L; Kumbar, Tukaram; Addepalli, Uday K; Bharti, Neha; Senthil, Sirisha; Choudhari, Nikhil S; Garudadri, Chandra S

2012-02-29

To evaluate the influence of a control group on the diagnostic accuracy of spectral-domain optical coherence tomography (SD-OCT) in early glaucoma. In a diagnostic, case-control study, 119 eyes of 60 normal subjects with no findings suspicious for glaucoma (control cohort 1); 76 eyes of 41 subjects referred by general ophthalmologists as glaucoma suspects based on optic disc morphology, but found by glaucoma experts to be normal but with physiological variations in their optic nerves (control cohort 2); and 65 eyes of 46 early-glaucoma patients (cases) underwent imaging of the optic nerve head (ONH), retinal nerve fiber layer (RNFL), and ganglion cell complex (GCC) by SD-OCT. Areas under the receiver operating characteristic curves (AUC) of ONH parameters discriminating glaucomatous eyes from normal eyes of control cohort 2 were significantly lesser (P < 0.001) than those discriminating glaucomatous eyes from normal eyes of control cohort 1. AUCs of RNFL parameters discriminating glaucomatous eyes from normal eyes of control cohorts 2 and 1 were comparable. Although the AUCs of GCC thickness parameters were comparable, AUCs of GCC focal and global loss volume in control cohort 2 (0.684 and 0.671. respectively) were significantly less (P < 0.05) than in control cohort 1 (0.881 and 0.841, respectively). The effectiveness of most SD-OCT parameters in detecting glaucoma significantly decreased when evaluated against a clinically relevant control group with suspicious-looking optic nerves compared with that against a control group consisting of normal subjects with no findings suspicious for glaucoma.

ELECTRICAL STUDIES ON THE COMPOUND EYE OF LIGIA OCCIDENTALIS DANA (CRUSTACEA: ISOPODA)

PubMed Central

Ruck, Philip; Jahn, Theodore L.

1954-01-01

The ERG of the compound eye in freshly collected Ligia occidentalis, in response to high intensity light flashes of ⅛ second or longer duration, begins with a negative on-effect quickly followed by an early positive deflection, rapidly returns to the baseline during illumination, and ends with a positive off-effect. As the stimulus intensity is decreased the early positivity progressively decreases and the rapid return to the baseline is replaced by a slowing decline of the negative on-effect. Responses were recorded with one active electrode subcorneally situated in the illuminated eye, the reference electrode in the dark eye. The dark-adapted eye shows a facilitation of the amplitude and rates of rise and fall of the on-effect to a brief, high intensity light stimulus. This facilitation may persist for more than 2 minutes. Following light adaptation under conditions in which the human eye loses sensitivity by a factor of almost 40,000 the Ligia eye loses sensitivity by a factor of only 3. The flicker fusion frequency of the ERG may be as high as 120/second with a corneal illumination of 15,000 foot-candles. Bleeding an otherwise intact animal very rapidly results in a decline of amplitude, change of wave form, and loss of facilitation in the ERG. When the eye is deganglionated without bleeding the animal the isolated retina responds in the same manner as the intact eye. Histological examination of the Ligia receptor layer showed that each ommatidium contains three different retinula cell types, each of which may be responsible for a different aspect of the ERG. PMID:13174786

Cancer through black eyes - The views of UK based black men towards cancer: A constructivist grounded theory study.

PubMed

Mulugeta, Betselot; Williamson, Susan; Monks, Rob; Hack, Thomas; Beaver, Kinta

2017-08-01

Little is known about black African (BA) and black African-Caribbean (BAC) men's views towards cancer; yet culture and acculturation can contribute to the way in which people understand, explain and develop their attitudes towards cancer. Hence, cancer prevention and early detection strategies may not be sensitive to United Kingdom (UK)-based black men's views, affecting their awareness of risk factors and early detection services. This study explored the views of UK-based BA and BAC men towards cancer. In collaboration with black community organisations based in four major cities in the UK, 25 participants were recruited using convenience and theoretical sampling methods. Data were collected using 33 semi-structured interviews, and analysed using grounded theory analytic procedures. One core category (cancer through black eyes) and seven sub-categories emerged; 'cultural views', 'religious beliefs', 'avoiding Babylon', 'alienation', 'suspicious mind', 'advertisements and information influence very little', and 'gap in service provision (bridging the gap)'. Participants' views towards cancer were linked to socially constructed perspectives, linked with cultural and religious beliefs, and shaped by what being a black male means in society. Risk factors such as smoking and obesity had different meanings and symbolisation through black eyes. There were macro- and micro-level similarities and differences between BA and BAC men. Cancer services and related public-health campaigns aimed at black men need to understand cancer through black eyes. Public health campaigns based solely on the clinical meaning of cancer are incongruent with black men's understandings of cancer, and therefore ineffective at reducing health inequality. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of brief daily periods of unrestricted vision during early monocular form deprivation on development of visual area 2.

PubMed

Zhang, Bin; Tao, Xiaofeng; Wensveen, Janice M; Harwerth, Ronald S; Smith, Earl L; Chino, Yuzo M

2011-09-14

Providing brief daily periods of unrestricted vision during early monocular form deprivation reduces the depth of amblyopia. To gain insights into the neural basis of the beneficial effects of this treatment, the binocular and monocular response properties of neurons were quantitatively analyzed in visual area 2 (V2) of form-deprived macaque monkeys. Beginning at 3 weeks of age, infant monkeys were deprived of clear vision in one eye for 12 hours every day until 21 weeks of age. They received daily periods of unrestricted vision for 0, 1, 2, or 4 hours during the form-deprivation period. After behavioral testing to measure the depth of the resulting amblyopia, microelectrode-recording experiments were conducted in V2. The ocular dominance imbalance away from the affected eye was reduced in the experimental monkeys and was generally proportional to the reduction in the depth of amblyopia in individual monkeys. There were no interocular differences in the spatial properties of V2 neurons in any subject group. However, the binocular disparity sensitivity of V2 neurons was significantly higher and binocular suppression was lower in monkeys that had unrestricted vision. The decrease in ocular dominance imbalance in V2 was the neuronal change most closely associated with the observed reduction in the depth of amblyopia. The results suggest that the degree to which extrastriate neurons can maintain functional connections with the deprived eye (i.e., reducing undersampling for the affected eye) is the most significant factor associated with the beneficial effects of brief periods of unrestricted vision.

Effects of Brief Daily Periods of Unrestricted Vision during Early Monocular Form Deprivation on Development of Visual Area 2

PubMed Central

Zhang, Bin; Tao, Xiaofeng; Wensveen, Janice M.; Harwerth, Ronald S.; Smith, Earl L.

2011-01-01

Purpose. Providing brief daily periods of unrestricted vision during early monocular form deprivation reduces the depth of amblyopia. To gain insights into the neural basis of the beneficial effects of this treatment, the binocular and monocular response properties of neurons were quantitatively analyzed in visual area 2 (V2) of form-deprived macaque monkeys. Methods. Beginning at 3 weeks of age, infant monkeys were deprived of clear vision in one eye for 12 hours every day until 21 weeks of age. They received daily periods of unrestricted vision for 0, 1, 2, or 4 hours during the form-deprivation period. After behavioral testing to measure the depth of the resulting amblyopia, microelectrode-recording experiments were conducted in V2. Results. The ocular dominance imbalance away from the affected eye was reduced in the experimental monkeys and was generally proportional to the reduction in the depth of amblyopia in individual monkeys. There were no interocular differences in the spatial properties of V2 neurons in any subject group. However, the binocular disparity sensitivity of V2 neurons was significantly higher and binocular suppression was lower in monkeys that had unrestricted vision. Conclusions. The decrease in ocular dominance imbalance in V2 was the neuronal change most closely associated with the observed reduction in the depth of amblyopia. The results suggest that the degree to which extrastriate neurons can maintain functional connections with the deprived eye (i.e., reducing undersampling for the affected eye) is the most significant factor associated with the beneficial effects of brief periods of unrestricted vision. PMID:21849427

Persistent hyperplastic primary vitreous in transgenic mice expressing IE180 of the pseudorabies virus.

PubMed

Taharaguchi, Satoshi; Yoshida, Kazuhiko; Tomioka, Yukiko; Yoshino, Saori; Uede, Toshimitsu; Ono, Etsuro

2005-05-01

Pseudorabies virus (PRV), a representative member of the alpha-herpesvirus family, causes nervous symptoms and ocular lesions, such as keratoconjunctivitis and retinal degeneration in piglets. The immediate-early protein IE180 of the PRV is known to be essential, not only in viral gene expression, but also in the cellular gene expression in host cells. The purpose of this study was to examine the effect of IE180 on the development of the mouse eye, by using transgenic technology. Transgenic mice expressing IE180 were generated and their eyes analyzed by histology, immunocytochemistry, and the bromodeoxyuridine cell proliferation assay. A fibrovascular retrolental tissue analogous to persistent hyperplastic primary vitreous (PHPV) in humans was observed in a transgenic mouse line expressing IE180. The gross anatomy of the eye showed white pupils. Analysis of hematoxylin and eosin-stained sections revealed that the retrolental tissue adhered to the neuroretina, the inner nuclear and ganglion cell layers were disorganized, and rosettelike arrangements of dysplastic photoreceptor cells were present. Bromodeoxyuridine-positive cells were detected in the retrolental tissues of postnatal day (P)1, P7, and P14 mice. The retrolental mass in the P7 transgenic mouse was composed of melanocytes and endothelial cells, which were detected by a cocktail of antibodies against endoglin, CD31, and VEGF receptor-2. The observation that the eye disease in transgenic mice is similar to that in PHPV in humans raises the possibility that expression of the immediate-early gene of alpha-herpesviruses may contribute to PHPV.

Diagnostic ability of macular ganglion cell asymmetry for glaucoma.

PubMed

Hwang, Young Hoon; Ahn, Sang Il; Ko, Sung Ju

2015-11-01

Using spectral-domain optical coherence tomography (OCT), this study aims to investigate the glaucoma diagnostic ability of macular ganglion cell asymmetry analysis. A cross-sectional study was conducted. This study was performed to investigate glaucoma diagnostic ability of macular ganglion cell asymmetry analysis in eyes with various degrees of glaucoma. We enrolled 181 healthy eyes and 265 glaucomatous eyes. Glaucomatous eyes were subdivided into pre-perimetric, early, moderate and advanced-to-severe glaucoma based on visual field test results. For each eye, macular ganglion cell-inner plexiform layer (GCIPL) thickness was measured using OCT. Average GCIPL thickness, GCIPL thicknesses in superior and inferior hemispheres, absolute difference in GCIPL thickness between superior and inferior hemispheres and GCIPL asymmetry index calculated as the absolute value of log10 (inferior hemisphere thickness/superior hemisphere thickness) were analysed. Areas under the receiver operating characteristics curves (AUCs) of GCIPL parameter were calculated and compared. All of the GCIPL parameters showed good glaucoma diagnostic ability (AUCs ≥ 0.817, P < 0.01). AUCs of average, superior and inferior GCIPL thickness increased as the severity of glaucoma increased. GCIPL thickness difference and asymmetry index showed the highest AUCs in early and moderate glaucoma and lower AUCs in pre-perimetric and advanced-to-severe glaucoma. GCIPL thickness difference and asymmetry index showed better glaucoma diagnostic ability than other GCIPL parameters only in early stage of glaucoma (P < 0.05); in other stages, these parameters had similar to or worse glaucoma diagnostic ability than other GCIPL parameters. Macular ganglion cell asymmetry analysis showed good glaucoma diagnostic ability, especially in early-stage glaucoma. However, it has limited usefulness in other stages of glaucoma. © 2015 Royal Australian and New Zealand College of Ophthalmologists.

The case from animal studies for balanced binocular treatment strategies for human amblyopia.

PubMed

Mitchell, Donald E; Duffy, Kevin R

2014-03-01

Although amblyopia typically manifests itself as a monocular condition, its origin has long been linked to unbalanced neural signals from the two eyes during early postnatal development, a view confirmed by studies conducted on animal models in the last 50 years. Despite recognition of its binocular origin, treatment of amblyopia continues to be dominated by a period of patching of the non-amblyopic eye that necessarily hinders binocular co-operation. This review summarizes evidence from three lines of investigation conducted on an animal model of deprivation amblyopia to support the thesis that treatment of amblyopia should instead focus upon procedures that promote and enhance binocular co-operation. First, experiments with mixed daily visual experience in which episodes of abnormal visual input were pitted against normal binocular exposure revealed that short exposures of the latter offset much longer periods of abnormal input to allow normal development of visual acuity in both eyes. Second, experiments on the use of part-time patching revealed that purposeful introduction of episodes of binocular vision each day could be very beneficial. Periods of binocular exposure that represented 30-50% of the daily visual exposure included with daily occlusion of the non-amblyopic could allow recovery of normal vision in the amblyopic eye. Third, very recent experiments demonstrate that a short 10 day period of total darkness can promote very fast and complete recovery of visual acuity in the amblyopic eye of kittens and may represent an example of a class of artificial environments that have similar beneficial effects. Finally, an approach is described to allow timing of events in kitten and human visual system development to be scaled to optimize the ages for therapeutic interventions. © 2014 The Authors Ophthalmic & Physiological Optics © 2014 The College of Optometrists.

Adrenal hormones interact with sympathetic innervation to modulate growth of embryonic heart in oculo.

PubMed

Tucker, D C; Torres, A

1992-02-01

To allow experimental manipulation of adrenal hormone and autonomic influences on developing myocardium without alteration of hemodynamic load, embryonic rat heart was cultured in the anterior eye chamber of an adult rat. Sympathetic innervation of embryonic day 12 heart grafts was manipulated by surgical sympathectomy of one eye chamber in each host rat. Adrenal hormone exposure was manipulated by host adrenal medullectomy (MEDX) in experiment 1 and by host adrenalectomy (ADX) in experiment 2. In experiment 1, whole heart grafts were larger in MEDX than in sham-operated hosts by 8 wk in oculo (6.14 +/- 0.71 vs. 5.09 +/- 0.69 mm2 with innervation intact and 7.97 +/- 2.07 vs. 3.09 +/- 0.63 mm2 with sympathetic innervation prevented). In experiment 2, host ADX increased growth of embryonic day 12 ventricles grafted into sympathectomized eye chambers (0.69 +/- 0.10 vs. 0.44 +/- 0.04 mm2) but did not affect growth of grafts in intact eye chambers (0.85 +/- 0.09 vs. 1.05 +/- 0.15 mm2). Corticosterone replacement (4 mg/day) entirely reversed the effect of host ADX on graft growth (superior cervical ganglionectomy, 0.47 +/- 0.03 mm2; intact eye chambers, 0.90 +/- 0.91 mm2). Beating rate of grafts was not affected by adrenal hormone manipulations. These experiments indicate that the compromised growth of embryonic heart grafts placed in sympathectomized eye chambers requires exposure to adult levels of glucocorticoids during the early days after grafting. These results suggest that interactions between neural and hormonal stimulation influence cardiac growth in the in oculo culture system and during normal development.

Resting-State Retinotopic Organization in the Absence of Retinal Input and Visual Experience

PubMed Central

Binda, Paola; Benson, Noah C.; Bridge, Holly; Watkins, Kate E.

2015-01-01

Early visual areas have neuronal receptive fields that form a sampling mosaic of visual space, resulting in a series of retinotopic maps in which the same region of space is represented in multiple visual areas. It is not clear to what extent the development and maintenance of this retinotopic organization in humans depend on retinal waves and/or visual experience. We examined the corticocortical receptive field organization of resting-state BOLD data in normally sighted, early blind, and anophthalmic (in which both eyes fail to develop) individuals and found that resting-state correlations between V1 and V2/V3 were retinotopically organized for all subject groups. These results show that the gross retinotopic pattern of resting-state connectivity across V1-V3 requires neither retinal waves nor visual experience to develop and persist into adulthood. SIGNIFICANCE STATEMENT Evidence from resting-state BOLD data suggests that the connections between early visual areas develop and are maintained even in the absence of retinal waves and visual experience. PMID:26354906

Influence of visual experience on developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei.

PubMed

Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Pettorossi, Vito Enrico

2004-11-01

The influence of visual experience deprivation on changes in synaptic plasticity during postnatal development was studied in the ventral part of the rat medial vestibular nuclei (vMVN). We analysed the differences in the occurrence, expressed as a percentage, of long-term depression (LTD) and long-term potentiation (LTP) induced by high frequency stimulation (HFS) of the primary vestibular afferents in rats reared in the light (LR) and those in the dark (DR). In LR rats, HFS only induced LTD in the early stages of development, but the occurrence of LTD progressively decreased to zero before their eyes opened, while that of LTP enhanced from zero to about 50%. Once the rats' eyes had opened, LTD was no longer inducible while LTP occurrence gradually reached the normal adult value (70%). In DR rats, a similar shift from LTD to LTP was observed before their eyes opened, showing only a slightly slower LTD decay and LTP growth, and the LTD annulment was delayed by 1 day. By contrast, the time courses of LTD and LTP development in DR and LR rats showed remarkable differences following eye opening. In fact, LTD occurrence increased to about 50% in a short period of time and remained high until the adult stage. In addition, the occurrence of LTP slowly decreased to less than 20%. The effect of light-deprivation was reversible, since the exposure of DR rats to light, 5 days after eye opening, caused a sudden disappearance of LTD and a partial recover of LTP occurrence. In addition, we observed that a week of light deprivation in LR adult rats did not affect the normal adult LTP occurrence. These results provide evidence that in a critical period of development visual input plays a crucial role in shaping synaptic plasticity of the vMVN, and suggest that the visual guided shift from LTD to LTP during development may be necessary to refine and consolidate vestibular circuitry.

Evidence for a potential role of glucagon during eye growth regulation in chicks.

PubMed

Feldkaemper, Marita P; Schaeffel, Frank

2002-01-01

Eye growth and refraction are regulated by visual processing in the retina. Until now, the messengers released by the retina to induce these changes are largely unknown. Previously, it was found that glucagon amacrine cells respond to defocus in the retinal image and even to its sign. The expression of the immediate-early gene product ZENK increased in this cell population in eyes wearing plus lenses and decreased in minus lens-treated chicks. Moreover, it was shown that the amount of retinal glucagon mRNA increased during treatment with positive lenses. Therefore, it seems likely that these cells contribute to the visual regulation of ocular growth and that glucagon may act as a stop signal for eye growth. The purpose of the present study was to accumulate further evidence for a role of glucagon in the visual control of eye growth. Chicks were treated with plus and minus lenses after injection of different amounts of the glucagon antagonist des-His1-Glu1-glucagon-amide or the agonist Lys17,18,Glu21-glucagon, respectively. Refractive development and eye growth were recorded by automated infrared photorefraction and A-scan ultrasound, respectively. The glucagon antagonist inhibited hyperopia development, albeit only in a narrow concentration range, and at most by 50%, but not myopia development. In contrast, the agonist inhibited myopia development in a dose-dependent fashion. At high concentrations, it also prevented hyperopia development. The amount of glucagon peptide in the retinae and choroids of lens-treated chicks and its diurnal variation was measured by using a radio-immunoassay. Retinal glucagon content decreased after minus lens treatment and choroidal glucagon content increased after plus lens treatment. No diurnal variation in the retinal amount of glucagon was detected. In addition, using an optokinetic nystagmus paradigm, the effect of glucagon and the antagonist des-His1-Glu9-glucagon-amide on suprathreshold contrast sensitivity was studied. Glucagon reduced contrast sensitivity (which might be linked to a signal for growth inhibition) whereas the antagonist des-His1-Glu9-glucagon-amide increased contrast sensitivity. The results of the study are in line with the hypothesis that glucagon plays a role in the visual control of eye growth in the chick.

Adaptability of the Immature Ocular Motor Control System: Unilateral IGF-1 Medial Rectus Treatment.

PubMed

Willoughby, Christy L; Fleuriet, Jérome; Walton, Mark M; Mustari, Michael J; McLoon, Linda K

2015-06-01

Unilateral treatment with sustained release IGF-1 to one medial rectus muscle in infant monkeys was performed to test the hypothesis that strabismus would develop as a result of changes in extraocular muscles during the critical period of development of binocularity. Sustained release IGF-1 pellets were implanted unilaterally on one medial rectus muscle in normal infant monkeys during the first 2 weeks of life. Eye position was monitored using standard photographic methods. After 3 months of treatment, myofiber and neuromuscular size, myosin composition, and innervation density were quantified in all rectus muscles and compared to those in age-matched controls. Sustained unilateral IGF-1 treatments resulted in strabismus for all treated subjects; 3 of the 4 subjects had a clinically significant strabismus of more than 10°. Both the treated medial rectus and the untreated ipsilateral antagonist lateral rectus muscles had significantly larger myofibers. No adaptation in myofiber size occurred in the contralateral functionally yoked lateral rectus or in myosin composition, neuromuscular junction size, or nerve density. Sustained unilateral IGF-1 treatment to extraocular muscles during the sensitive period of development of orthotropic eye alignment and binocularity was sufficient to disturb ocular motor development, resulting in strabismus in infant monkeys. This could be due to altering fusion of gaze during the early sensitive period. Serial measurements of eye alignment suggested the IGF-1-treated infants received insufficient coordinated binocular experience, preventing the establishment of normal eye alignment. Our results uniquely suggest that abnormal signaling by the extraocular muscles may be a cause of strabismus.

Adaptability of the Immature Ocular Motor Control System: Unilateral IGF-1 Medial Rectus Treatment

PubMed Central

Willoughby, Christy L.; Fleuriet, Jérome; Walton, Mark M.; Mustari, Michael J.; McLoon, Linda K.

2015-01-01

Purpose. Unilateral treatment with sustained release IGF-1 to one medial rectus muscle in infant monkeys was performed to test the hypothesis that strabismus would develop as a result of changes in extraocular muscles during the critical period of development of binocularity. Methods. Sustained release IGF-1 pellets were implanted unilaterally on one medial rectus muscle in normal infant monkeys during the first 2 weeks of life. Eye position was monitored using standard photographic methods. After 3 months of treatment, myofiber and neuromuscular size, myosin composition, and innervation density were quantified in all rectus muscles and compared to those in age-matched controls. Results. Sustained unilateral IGF-1 treatments resulted in strabismus for all treated subjects; 3 of the 4 subjects had a clinically significant strabismus of more than 10°. Both the treated medial rectus and the untreated ipsilateral antagonist lateral rectus muscles had significantly larger myofibers. No adaptation in myofiber size occurred in the contralateral functionally yoked lateral rectus or in myosin composition, neuromuscular junction size, or nerve density. Conclusions. Sustained unilateral IGF-1 treatment to extraocular muscles during the sensitive period of development of orthotropic eye alignment and binocularity was sufficient to disturb ocular motor development, resulting in strabismus in infant monkeys. This could be due to altering fusion of gaze during the early sensitive period. Serial measurements of eye alignment suggested the IGF-1-treated infants received insufficient coordinated binocular experience, preventing the establishment of normal eye alignment. Our results uniquely suggest that abnormal signaling by the extraocular muscles may be a cause of strabismus. PMID:26030103

New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation

NASA Astrophysics Data System (ADS)

Irsch, Kristina; Gramatikov, Boris I.; Wu, Yi-Kai; Guyton, David L.

2014-06-01

Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach.

New pediatric vision screener employing polarization-modulated, retinal-birefringence-scanning-based strabismus detection and bull's eye focus detection with an improved target system: opto-mechanical design and operation.

PubMed

Irsch, Kristina; Gramatikov, Boris I; Wu, Yi-Kai; Guyton, David L

2014-06-01

Amblyopia ("lazy eye") is a major public health problem, caused by misalignment of the eyes (strabismus) or defocus. If detected early in childhood, there is an excellent response to therapy, yet most children are detected too late to be treated effectively. Commercially available vision screening devices that test for amblyopia's primary causes can detect strabismus only indirectly and inaccurately via assessment of the positions of external light reflections from the cornea, but they cannot detect the anatomical feature of the eyes where fixation actually occurs (the fovea). Our laboratory has been developing technology to detect true foveal fixation, by exploiting the birefringence of the uniquely arranged Henle fibers delineating the fovea using retinal birefringence scanning (RBS), and we recently described a polarization-modulated approach to RBS that enables entirely direct and reliable detection of true foveal fixation, with greatly enhanced signal-to-noise ratio and essentially independent of corneal birefringence (a confounding variable with all polarization-sensitive ophthalmic technology). Here, we describe the design and operation of a new pediatric vision screener that employs polarization-modulated, RBS-based strabismus detection and bull's eye focus detection with an improved target system, and demonstrate the feasibility of this new approach.

Spatial scale and distribution of neurovascular signals underlying decoding of orientation and eye of origin from fMRI data

PubMed Central

Harrison, Charlotte; Jackson, Jade; Oh, Seung-Mock; Zeringyte, Vaida

2016-01-01

Multivariate pattern analysis of functional magnetic resonance imaging (fMRI) data is widely used, yet the spatial scales and origin of neurovascular signals underlying such analyses remain unclear. We compared decoding performance for stimulus orientation and eye of origin from fMRI measurements in human visual cortex with predictions based on the columnar organization of each feature and estimated the spatial scales of patterns driving decoding. Both orientation and eye of origin could be decoded significantly above chance in early visual areas (V1–V3). Contrary to predictions based on a columnar origin of response biases, decoding performance for eye of origin in V2 and V3 was not significantly lower than that in V1, nor did decoding performance for orientation and eye of origin differ significantly. Instead, response biases for both features showed large-scale organization, evident as a radial bias for orientation, and a nasotemporal bias for eye preference. To determine whether these patterns could drive classification, we quantified the effect on classification performance of binning voxels according to visual field position. Consistent with large-scale biases driving classification, binning by polar angle yielded significantly better decoding performance for orientation than random binning in V1–V3. Similarly, binning by hemifield significantly improved decoding performance for eye of origin. Patterns of orientation and eye preference bias in V2 and V3 showed a substantial degree of spatial correlation with the corresponding patterns in V1, suggesting that response biases in these areas originate in V1. Together, these findings indicate that multivariate classification results need not reflect the underlying columnar organization of neuronal response selectivities in early visual areas. NEW & NOTEWORTHY Large-scale response biases can account for decoding of orientation and eye of origin in human early visual areas V1–V3. For eye of origin this pattern is a nasotemporal bias; for orientation it is a radial bias. Differences in decoding performance across areas and stimulus features are not well predicted by differences in columnar-scale organization of each feature. Large-scale biases in extrastriate areas are spatially correlated with those in V1, suggesting biases originate in primary visual cortex. PMID:27903637

Social anxiety and detection of facial untrustworthiness: Spatio-temporal oculomotor profiles.

PubMed

Gutiérrez-García, Aida; Calvo, Manuel G; Eysenck, Michael W

2018-04-01

Cognitive models posit that social anxiety is associated with biased attention to and interpretation of ambiguous social cues as threatening. We investigated attentional bias (selective early fixation on the eye region) to account for the tendency to distrust ambiguous smiling faces with non-happy eyes (interpretative bias). Eye movements and fixations were recorded while observers viewed video-clips displaying dynamic facial expressions. Low (LSA) and high (HSA) socially anxious undergraduates with clinical levels of anxiety judged expressers' trustworthiness. Social anxiety was unrelated to trustworthiness ratings for faces with congruent happy eyes and a smile, and for neutral expressions. However, social anxiety was associated with reduced trustworthiness rating for faces with an ambiguous smile, when the eyes slightly changed to neutrality, surprise, fear, or anger. Importantly, HSA observers looked earlier and longer at the eye region, whereas LSA observers preferentially looked at the smiling mouth region. This attentional bias in social anxiety generalizes to all the facial expressions, while the interpretative bias is specific for ambiguous faces. Such biases are adaptive, as they facilitate an early detection of expressive incongruences and the recognition of untrustworthy expressers (e.g., with fake smiles), with no false alarms when judging truly happy or neutral faces. Copyright © 2018 Elsevier B.V. All rights reserved.

Differential Attention to Faces in Infant Siblings of Children with Autism Spectrum Disorder and Associations with Later Social and Language Ability

ERIC Educational Resources Information Center

Wagner, Jennifer; Luyster, Rhiannon J.; Moustapha, Hana; Tager-Flusberg, Helen; Nelson, Charles Alexander

2018-01-01

A growing body of literature has begun to explore social attention in infant siblings of children with autism spectrum disorder (ASD) with hopes of identifying early differences that are associated with later ASD or other aspects of development. The present study used eye-tracking to familiar (mother) and unfamiliar (stranger) faces in two groups…

A special role for binocular visual input during development and as a component of occlusion therapy for treatment of amblyopia.

PubMed

Mitchell, Donald E

2008-01-01

To review work on animal models of deprivation amblyopia that points to a special role for binocular visual input in the development of spatial vision and as a component of occlusion (patching) therapy for amblyopia. The studies reviewed employ behavioural methods to measure the effects of various early experiential manipulations on the development of the visual acuity of the two eyes. Short periods of concordant binocular input, if continuous, can offset much longer daily periods of monocular deprivation to allow the development of normal visual acuity in both eyes. It appears that the visual system does not weigh all visual input equally in terms of its ability to impact on the development of vision but instead places greater weight on concordant binocular exposure. Experimental models of patching therapy for amblyopia imposed on animals in which amblyopia had been induced by a prior period of early monocular deprivation, indicate that the benefits of patching therapy may be only temporary and decline rapidly after patching is discontinued. However, when combined with critical amounts of binocular visual input each day, the benefits of patching can be both heightened and made permanent. Taken together with demonstrations of retained binocular connections in the visual cortex of monocularly deprived animals, a strong argument is made for inclusion of specific training of stereoscopic vision for part of the daily periods of binocular exposure that should be incorporated as part of any patching protocol for amblyopia.

The Evolution and Development of Neural Superposition

PubMed Central

Agi, Egemen; Langen, Marion; Altschuler, Steven J.; Wu, Lani F.; Zimmermann, Timo

2014-01-01

Visual systems have a rich history as model systems for the discovery and understanding of basic principles underlying neuronal connectivity. The compound eyes of insects consist of up to thousands of small unit eyes that are connected by photoreceptor axons to set up a visual map in the brain. The photoreceptor axon terminals thereby represent neighboring points seen in the environment in neighboring synaptic units in the brain. Neural superposition is a special case of such a wiring principle, where photoreceptors from different unit eyes that receive the same input converge upon the same synaptic units in the brain. This wiring principle is remarkable, because each photoreceptor in a single unit eye receives different input and each individual axon, among thousands others in the brain, must be sorted together with those few axons that have the same input. Key aspects of neural superposition have been described as early as 1907. Since then neuroscientists, evolutionary and developmental biologists have been fascinated by how such a complicated wiring principle could evolve, how it is genetically encoded, and how it is developmentally realized. In this review article, we will discuss current ideas about the evolutionary origin and developmental program of neural superposition. Our goal is to identify in what way the special case of neural superposition can help us answer more general questions about the evolution and development of genetically “hard-wired” synaptic connectivity in the brain. PMID:24912630

The evolution and development of neural superposition.

PubMed

Agi, Egemen; Langen, Marion; Altschuler, Steven J; Wu, Lani F; Zimmermann, Timo; Hiesinger, Peter Robin

2014-01-01

Visual systems have a rich history as model systems for the discovery and understanding of basic principles underlying neuronal connectivity. The compound eyes of insects consist of up to thousands of small unit eyes that are connected by photoreceptor axons to set up a visual map in the brain. The photoreceptor axon terminals thereby represent neighboring points seen in the environment in neighboring synaptic units in the brain. Neural superposition is a special case of such a wiring principle, where photoreceptors from different unit eyes that receive the same input converge upon the same synaptic units in the brain. This wiring principle is remarkable, because each photoreceptor in a single unit eye receives different input and each individual axon, among thousands others in the brain, must be sorted together with those few axons that have the same input. Key aspects of neural superposition have been described as early as 1907. Since then neuroscientists, evolutionary and developmental biologists have been fascinated by how such a complicated wiring principle could evolve, how it is genetically encoded, and how it is developmentally realized. In this review article, we will discuss current ideas about the evolutionary origin and developmental program of neural superposition. Our goal is to identify in what way the special case of neural superposition can help us answer more general questions about the evolution and development of genetically "hard-wired" synaptic connectivity in the brain.

Combatting Terrorism through Study of the Genetic Psychology of Terrorist Leaders. The Early Development of the Terrorist Mind

DTIC Science & Technology

1989-12-01

that many aspects of appearance are inherited. Genetic factors determine such characteristics as sex, eye color, texture and color of skin and hair...characteris- tics are important and link child to parent(s). If an individual can inherit physical characteristics from his parents, why not behavioral... characteristics ? Is there any truth in the saying: "If you want to know what iPaul H. Mussen, The Psychological Development of the child (New Jersey

Multifocal blue-on-yellow visual evoked potentials in early glaucoma.

PubMed

Klistorner, Alexander; Graham, Stuart L; Martins, Alessandra; Grigg, John R; Arvind, Hemamalini; Kumar, Rajesh S; James, Andrew C; Billson, Francis A

2007-09-01

To determine the sensitivity and specificity of blue-on-yellow multifocal visual evoked potentials (mfVEPs) in early glaucoma. Cross-sectional study. Fifty patients with a confirmed diagnosis of early glaucoma and 60 normal participants. Black-and-white mfVEPs and blue-on-yellow mfVEPs were recorded using the Accumap version 2.0 (ObjectiVision Pty. Ltd., Sydney, Australia). All patients also underwent achromatic standard automated perimetry (SAP). Multifocal VEP amplitude and latency values in glaucoma patients were analyzed and compared with those of the normal controls. Based on the definition of visual field defect, in the group of glaucomatous eyes with SAP defects, amplitude of blue-on-yellow mfVEP was abnormal in all 64 cases (100% sensitivity), whereas black-and-white mfVEP missed 5 cases (92.2% sensitivity). Generally, larger scotomata were noted on blue-on-yellow mfVEP compared with black-and-white mfVEP for the same eyes. There was high topographic correspondence between SAP and amplitude of blue-on-yellow mfVEP and significant (P<0.0001) correlation between them (correlation coefficient, 0.73). Abnormal amplitude was detected in 3 of 60 eyes of control subjects (95% specificity). There was, however, no correlation between visual field defect and latency delay in glaucoma patients. Although there was a significant difference between averaged latency of control and glaucoma eyes, values considerably overlapped. The blue-on-yellow mfVEP is a sensitive and specific tool for detecting early glaucoma based on amplitude analysis.

Early surgical managment of penetrating ocular injuries involving the posterior segment.

PubMed

Michels, R G

1976-09-01

Pars plana vitrectomy technic can be used in the early management of certain penetrating ocular injuries involving the posterior segment, including selected intraocular foreign bodies. This study reports the results of ten consecutive cases of intraocular foreign bodies in the posterior segment treated by a combination of vitrectomy (including lensectomy when necessary) and foreign-body extraction with forceps. The foreign body was successfully removed in nine of ten eyes, and nine of ten eyes were salvaged. This favorable experience using early vitreous surgery suggests that the vitrectomy technic can be used in other penetrating injuries involving the posterior segment that are not associated with intraocular foreign bodies. Possible indications for early vitrectomy are presented, including cases with a poor prognosis when managed by conventional methods.

A novel approach to training attention and gaze in ASD: A feasibility and efficacy pilot study.

PubMed

Chukoskie, Leanne; Westerfield, Marissa; Townsend, Jeanne

2018-05-01

In addition to the social, communicative and behavioral symptoms that define the disorder, individuals with ASD have difficulty re-orienting attention quickly and accurately. Similarly, fast re-orienting saccadic eye movements are also inaccurate and more variable in both endpoint and timing. Atypical gaze and attention are among the earliest symptoms observed in ASD. Disruption of these foundation skills critically affects the development of higher level cognitive and social behavior. We propose that interventions aimed at these early deficits that support social and cognitive skills will be broadly effective. We conducted a pilot clinical trial designed to demonstrate the feasibility and preliminary efficacy of using gaze-contingent video games for low-cost in-home training of attention and eye movement. Eight adolescents with ASD participated in an 8-week training, with pre-, mid- and post-testing of eye movement and attention control. Six of the eight adolescents completed the 8 weeks of training and all six showed improvement in attention (orienting, disengagement) and eye movement control or both. All game systems remained intact for the duration of training and all participants could use the system independently. We delivered a robust, low-cost, gaze-contingent game system for home use that, in our pilot training sample, improved the attention orienting and eye movement performance of adolescent participants in 8 weeks of training. We are currently conducting a clinical trial to replicate these results and to examine what, if any, aspects of training transfer to more real-world tasks. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 546-554, 2018. © 2017 Wiley Periodicals, Inc.

Eye Tracking Dysfunction in Schizophrenia: Characterization and Pathophysiology

PubMed Central

Sereno, Anne B.; Gooding, Diane C.; O’Driscoll, Gilllian A.

2011-01-01

Eye tracking dysfunction (ETD) is one of the most widely replicated behavioral deficits in schizophrenia and is over-represented in clinically unaffected first-degree relatives of schizophrenia patients. Here, we provide an overview of research relevant to the characterization and pathophysiology of this impairment. Deficits are most robust in the maintenance phase of pursuit, particularly during the tracking of predictable target movement. Impairments are also found in pursuit initiation and correlate with performance on tests of motion processing, implicating early sensory processing of motion signals. Taken together, the evidence suggests that ETD involves higher-order structures, including the frontal eye fields, which adjust the gain of the pursuit response to visual and anticipated target movement, as well as early parts of the pursuit pathway, including motion areas (the middle temporal area and the adjacent medial superior temporal area). Broader application of localizing behavioral paradigms in patient and family studies would be advantageous for refining the eye tracking phenotype for genetic studies. PMID:21312405

Can infants' orientation to social stimuli predict later joint attention skills?

PubMed

Schietecatte, Inge; Roeyers, Herbert; Warreyn, Petra

2012-06-01

From the moment infants are born, they seem to prefer orienting to social stimuli, over objects and non-social stimuli. This preference lasts throughout adulthood and is believed to play a crucial role in social-communicative development. By following up a group of infants at the age of 6, 8, and 12 months, this study explored the role of social orienting in the early development of joint attention skills. The expected association between social orienting and joint attention was partially confirmed. Social orienting in real-life photographs of everyday situations was not related to later joint attention skills, however fixation to the eyes in a neutral face was related to response to joint attention skills, and fixation to the eyes in a dynamic video clip of a talking person was predictive of initiating joint attention skills. Several alternative interpretations of the results are discussed. ©2011 The British Psychological Society.

Prophylactic laser in age-related macular degeneration: the past, the present and the future.

PubMed

Findlay, Quan; Jobling, Andrew I; Vessey, Kirstan A; Greferath, Ursula; Phipps, Joanna A; Guymer, Robyn H; Fletcher, Erica L

2018-05-01

The presence of drusen in the posterior eye is a hallmark feature of the early stages of age-related macular degeneration and their size is an indicator of risk of progression to vision-threatening forms of the disease. Since the initial observations that laser treatment can resolve drusen, there has been great interest in whether laser treatment can be used to reduce the progression of age-related macular degeneration. In this article, we review the development of lasers for the treatment of those with age-related macular degeneration. We provide an overview of the clinical trial results that demonstrated drusen resolution but that had mixed effects on progression of disease. In addition, we provide a summary of the recent developments in pulsed lasers that are designed to reduce the energy applied to the posterior eye to provide the therapeutic effects of conventional continuous wave lasers while reducing the secondary tissue effects.

Retinoblastoma: A Three-Year-Study at a Brazilian Medical School Hospital

PubMed Central

Bonanomi, Maria Teresa Brizzi Chizzotti; de Almeida, Maria Tereza Assis; Cristofani, Lilian Maria; Filho, Vicente Odone

2009-01-01

OBJECTIVE: To present the characteristics and treatment outcomes of patients with retinoblastoma. METHODS: A retrospective case series was conducted to review the records of all new patients diagnosed with retinoblastoma between 2003 and 2005. Eyes with early disease, or advanced disease with potential vision were treated with chemotherapy (carboplatin and etoposide) in conjunction with early local therapy (laser or cryo). Radiotherapy was used in cases where the disease did not respond to the above protocols or in recurrent cases. Eyes in the late stage of disease with no potential vision in the initial examination or eyes and where conservative treatment had failed were enucleated. RESULTS: In total, we reviewed 28 new cases of retinoblastoma, 15 of which were unilateral and 13 of which were bilateral (46%). These data correspond to a mean of 9.3 new cases per year (0.77 case/month). The mean age at diagnosis was 33.8 months for unilateral cases, and 19.15 months for bilateral cases (p=0.015). Leucocoria was the major presenting symptom (75%). All but one patient with unilateral disease had the affected eye enucleated due to advanced disease (mean follow-up: 39.91 months). Among the 13 bilateral cases, 13 eyes (50%) were enucleated, 11 eyes (42.4%) were saved with chemotherapy in conjunction with local therapy and 2 eyes (7.6%) were saved using external beam radiotherapy (mean follow-up: 41.91 months). In unilateral and bilateral disease, pathology data revealed choroid involvement in 50% and 30%, respectively, and optic nerve invasion in 92% and 50%, respectively. CONCLUSION: In this population, retinoblastoma was diagnosed too late and most eyes were consequently enucleated. In cases with bilateral disease, half of the eyes were preserved. PMID:19488609

An Integrative Model for the Neural Mechanism of Eye Movement Desensitization and Reprocessing (EMDR)

PubMed Central

Coubard, Olivier A.

2016-01-01

Since the seminal report by Shapiro that bilateral stimulation induces cognitive and emotional changes, 26 years of basic and clinical research have examined the effects of Eye Movement Desensitization and Reprocessing (EMDR) in anxiety disorders, particularly in post-traumatic stress disorder (PTSD). The present article aims at better understanding EMDR neural mechanism. I first review procedural aspects of EMDR protocol and theoretical hypothesis about EMDR effects, and develop the reasons why the scientific community is still divided about EMDR. I then slide from psychology to physiology describing eye movements/emotion interaction from the physiological viewpoint, and introduce theoretical and technical tools used in movement research to re-examine EMDR neural mechanism. Using a recent physiological model for the neuropsychological architecture of motor and cognitive control, the Threshold Interval Modulation with Early Release-Rate of rIse Deviation with Early Release (TIMER-RIDER)—model, I explore how attentional control and bilateral stimulation may participate to EMDR effects. These effects may be obtained by two processes acting in parallel: (i) activity level enhancement of attentional control component; and (ii) bilateral stimulation in any sensorimotor modality, both resulting in lower inhibition enabling dysfunctional information to be processed and anxiety to be reduced. The TIMER-RIDER model offers quantitative predictions about EMDR effects for future research about its underlying physiological mechanisms. PMID:27092064

The eyes reveal uncertainty about object distinctions in semantic variant primary progressive aphasia.

PubMed

Faria, Andreia V; Race, David; Kim, Kevin; Hillis, Argye E

2018-06-01

At least three distinct variants of primary progressive aphasia (PPA) have been described, but they are difficult to distinguish early in the course, when individuals experience primarily anomia. People with svPPA are often the hardest to care for, because they have impaired comprehension of words and objects and often have negative changes in comportment. We sought to identify an early marker of semantic variant primary progressive aphasia (svPPA) and to enhance the understanding of the semantic deficit in svPPA. We hypothesized that the pattern of eye tracking in a word picture matching task can differentiate svPPA from other variants and can predict which participants with unclassifiable PPA will progress to svPPA. We tested 19 individuals with PPA on a word picture matching task with eye tracking. We found that individuals with svPPA were less accurate than other variants when the foils were semantic coordinates (horse-cow) or schematically related (horse-saddle), but not when they were thematically related (saw-horse) or unrelated. Moreover, even in the condition in which they were highly accurate (unrelated foils) they looked much more often to the foils and for longer, than other variants or controls. Unclassifiable PPA participants who eventually developed svPPA showed the same pattern. This abnormal pattern was associated with atrophy in bilateral temporal poles. Copyright © 2018. Published by Elsevier Ltd.

Ahmed Glaucoma Valve Implantation in Vitrectomized Eyes

PubMed Central

İmamoğlu, Serhat

2018-01-01

Purpose To evaluate the outcomes of Ahmed glaucoma valve (AGV) implantation in vitrectomized eyes. Materials and Methods The medical records of 13 eyes that developed glaucoma due to emulsified silicon oil or neovascularization following pars plana vitrectomy and underwent AGV implantation were retrospectively reviewed. The main outcome measures were intraocular pressure (IOP), best-corrected visual acuity (BCVA), number of antiglaucoma medications, and postoperative complications. Surgical success was defined as last IOP ≤21 mmHg or ≥6 mmHg and without loss of light perception. Results The mean follow-up duration was 11.7 ± 5.5 (range, 6–23) months. The mean IOP before the AGV implantation was 37.9 ± 6.7 mmHg with an average of 3.5 ± 1.2 drugs. At the final visit, the mean IOP was 15.9 ± 4.6 mmHg (p=0.001) and the mean number of glaucoma medications decreased to 2.3 ± 1.3 (p=0.021). At the last visit, 11 eyes (84.4%) had stable or improved VA and one eye (7.7%) had a final VA of no light perception. Surgical success was achieved in 11 of the 13 eyes (84.4%). Postoperative complications were bleb encapsulation (69.2%), early hypotony (38.5%), hyphema (23.1%), decompression retinopathy (23.1%), choroidal detachment (15.4%), intraocular hemorrhage (7.7%), and late endophthalmitis (7.7%). One eye (7.7%) was enucleated because of late endophthalmitis. Conclusions Despite complications necessitating medical and surgical interventions, vitrectomized eyes were effectively managed with AGV implantation. PMID:29862068

Brief report: Do children with autism gather information from social contexts to aid their word learning?

PubMed

Jing, Wei; Fang, Junming

2014-06-01

Typically developing (TD) infants could capitalize on social eye gaze and social contexts to aid word learning. Although children with autism disorder (AD) are known to exhibit atypicality in word learning via social eye gaze, their ability to utilize social contexts for word learning is not well understood. We investigated whether verbal AD children exhibit word learning ability via social contextual cues by late childhood. We found that AD children, unlike TD controls, failed to infer the speaker’s referential intention through information gathered from the social context. This suggests that TD children can learn words in diverse social pragmatic contexts in as early as toddlerhood whereas AD children are still unable to do so by late childhood.

Retcam fluorescein gonioangiography: a new modality for early detection of angle neovascularization in diabetic retinopathy.

PubMed

Azad, Rajvardhan; Arora, Tarun; Sihota, Ramanjit; Chandra, Parijat; Mahajan, Deepankur; Sain, Siddarth; Sharma, Yograj

2013-10-01

To evaluate the role of Retcam fluorescein gonioangiography in detecting neovascularization of the angle and correlate the same with gonioscopy in diabetic retinopathy. One hundred and fifty eyes of 150 patients (25 each of mild, moderate, severe, very severe nonproliferative diabetic retinopathy (NPDR) proliferative diabetic retinopathy (PDR); and PDR with high-risk characteristics) were recruited. They underwent complete ocular examination including applanation tonometry, gonioscopy, Retcam fluorescein gonioangiography, and fundus fluorescein angiography. Using Retcam fluorescein gonioangiography, of 150 eyes neovascularization of the angle was detected in 37 eyes (24.66%) compared with 22 eyes (14.66%) on gonioscopy (P = 0.04). Small newly formed vessels were evident only with Retcam fluorescein gonioangiography. In 10 of 50 patients (20%) with severe/very severe NPDR, angle neovascularization was appreciable on Retcam fluorescein angiography compared with 5 patients (10%) on gonioscopy. Similarly, 25 of 50 patients (50%) with PDR/PDR with high-risk characteristics had neovascularization of the angle on Retcam gonioangiography compared with 17 (34%) on gonioscopy. Retcam fluorescein gonioangiography is a novel technique for early detection of angle neovascularization in diabetic retinopathy and hence preventing progression to neovascular glaucoma. The objective nature of this test helps in precise decision making compared with gonioscopy for early intervention especially in cases of pre-PDR.

The History of Otolaryngology In New Orleans.

PubMed

Lyons, George D

2016-01-01

George D. Lyons, MD, now becoming "an elder statesman," he decided summarize the early history of otolaryngology as it developed in New Orleans. Francis LeJeune, MD, Sr., a much admired and loved otolaryngologist, has afforded a great insight through his memoirs in the early development of our specialty in his report of Otolaryngology in the South. Dr. LeJune, Sr. began his brief paper just before his death. Excerpts from this paper have been used by the American Laryngological Association. There will be no bibliography. Most of this information was obtained from Dr. LeJeune's memoirs, history departments of the Academy, Touro Infirmary, Eye, Ear, Nose, and Throat (EENT) archives and interviews with descendants of our early leaders. A special thanks to them for their time, research, and generosity of information. There has been some debate regarding the precision of some of the dates, but they are as chronologically accurate as possible.

Vision Screening of School Children by Teachers as a Community Based Strategy to Address the Challenges of Childhood Blindness.

PubMed

Kaur, Gurvinder; Koshy, Jacob; Thomas, Satish; Kapoor, Harpreet; Zachariah, Jiju George; Bedi, Sahiba

2016-04-01

Early detection and treatment of vision problems in children is imperative to meet the challenges of childhood blindness. Considering the problems of inequitable distribution of trained manpower and limited access of quality eye care services to majority of our population, innovative community based strategies like 'Teachers training in vision screening' need to be developed for effective utilization of the available human resources. To evaluate the effectiveness of introducing teachers as the first level vision screeners. Teacher training programs were conducted for school teachers to educate them about childhood ocular disorders and the importance of their early detection. Teachers from government and semi-government schools located in Ludhiana were given training in vision screening. These teachers then conducted vision screening of children in their schools. Subsequently an ophthalmology team visited these schools for re-evaluation of children identified with low vision. Refraction was performed for all children identified with refractive errors and spectacles were prescribed. Children requiring further evaluation were referred to the base hospital. The project was done in two phases. True positives, false positives, true negatives and false negatives were calculated for evaluation. In phase 1, teachers from 166 schools underwent training in vision screening. The teachers screened 30,205 children and reported eye problems in 4523 (14.97%) children. Subsequently, the ophthalmology team examined 4150 children and confirmed eye problems in 2137 children. Thus, the teachers were able to correctly identify eye problems (true positives) in 47.25% children. Also, only 13.69% children had to be examined by the ophthalmology team, thus reducing their work load. Similarly, in phase 2, 46.22% children were correctly identified to have eye problems (true positives) by the teachers. By random sampling, 95.65% children were correctly identified as normal (true negatives) by the teachers. Considering the high true negative rates and reasonably good true positive rates and the wider coverage provided by the program, vision screening in schools by teachers is an effective method of identifying children with low vision. This strategy is also valuable in reducing the workload of the eye care staff.

[Knowledge about the relationship through protagonist-director interactions in psychodrama groups].

PubMed

Erdélyi, Ildikó

2005-01-01

This report follows emotional behavior in two psychodrama groups from the "present moment" until "moment of contact" using the Consensus Rorschach method. In the analysis of verbal and nonverbal material of protagonist-director dyads the following patterns were distinguished: a) early relationship patterns; b) affective attunement; c) fit of knowledge about the relationship. The author describes the relationship between the concept of "present moment" in therapy and the role of eye contact. Eye contact produces emotional tension in the context of the "present moment". Moments of contact, however, require implicit and explicit knowledge about the relationship to be constructed simultaneously as well as development of affective interactions. Emotional impulses are stored in implicit memory, which has no immediate availability. However, therapy--including psychodrama--attaches words to behaviors that are beyond the verbal levels as well, and therefore it extends the domain of memory. This is the way in which non-symbolized emotional behavior (including eye contact) and the play's verbal level with symbolic representations of memories are interconnected.

Cognitive load disrupts implicit theory-of-mind processing.

PubMed

Schneider, Dana; Lam, Rebecca; Bayliss, Andrew P; Dux, Paul E

2012-08-01

Eye movements in Sally-Anne false-belief tasks appear to reflect the ability to implicitly monitor the mental states of other individuals (theory of mind, or ToM). It has recently been proposed that an early-developing, efficient, and automatically operating ToM system subserves this ability. Surprisingly absent from the literature, however, is an empirical test of the influence of domain-general executive processing resources on this implicit ToM system. In the study reported here, a dual-task method was employed to investigate the impact of executive load on eye movements in an implicit Sally-Anne false-belief task. Under no-load conditions, adult participants displayed eye movement behavior consistent with implicit belief processing, whereas evidence for belief processing was absent for participants under cognitive load. These findings indicate that the cognitive system responsible for implicitly tracking beliefs draws at least minimally on executive processing resources. Thus, even the most low-level processing of beliefs appears to reflect a capacity-limited operation.

Personalized ophthalmology.

PubMed

Porter, L F; Black, G C M

2014-07-01

Ophthalmology has been an early adopter of personalized medicine. Drawing on genomic advances to improve molecular diagnosis, such as next-generation sequencing, and basic and translational research to develop novel therapies, application of genetic technologies in ophthalmology now heralds development of gene replacement therapies for some inherited monogenic eye diseases. It also promises to alter prediction, diagnosis and management of the complex disease age-related macular degeneration. Personalized ophthalmology is underpinned by an understanding of the molecular basis of eye disease. Two important areas of focus are required for adoption of personalized approaches: disease stratification and individualization. Disease stratification relies on phenotypic and genetic assessment leading to molecular diagnosis; individualization encompasses all aspects of patient management from optimized genetic counseling and conventional therapies to trials of novel DNA-based therapies. This review discusses the clinical implications of these twin strategies. Advantages and implications of genetic testing for patients with inherited eye diseases, choice of molecular diagnostic modality, drivers for adoption of personalized ophthalmology, service planning implications, ethical considerations and future challenges are considered. Indeed, whilst many difficulties remain, personalized ophthalmology truly has the potential to revolutionize the specialty. © 2014 The Authors. Clinical Genetics published by JohnWiley & Sons A/S. Published by John Wiley & Sons Ltd.

Optimal Eye-Gaze Fixation Position for Face-Related Neural Responses

PubMed Central

Zerouali, Younes; Lina, Jean-Marc; Jemel, Boutheina

2013-01-01

It is generally agreed that some features of a face, namely the eyes, are more salient than others as indexed by behavioral diagnosticity, gaze-fixation patterns and evoked-neural responses. However, because previous studies used unnatural stimuli, there is no evidence so far that the early encoding of a whole face in the human brain is based on the eyes or other facial features. To address this issue, scalp electroencephalogram (EEG) and eye gaze-fixations were recorded simultaneously in a gaze-contingent paradigm while observers viewed faces. We found that the N170 indexing the earliest face-sensitive response in the human brain was the largest when the fixation position is located around the nasion. Interestingly, for inverted faces, this optimal fixation position was more variable, but mainly clustered in the upper part of the visual field (around the mouth). These observations extend the findings of recent behavioral studies, suggesting that the early encoding of a face, as indexed by the N170, is not driven by the eyes per se, but rather arises from a general perceptual setting (upper-visual field advantage) coupled with the alignment of a face stimulus to a stored face template. PMID:23762224

Optimal eye-gaze fixation position for face-related neural responses.

PubMed

Zerouali, Younes; Lina, Jean-Marc; Jemel, Boutheina

2013-01-01

It is generally agreed that some features of a face, namely the eyes, are more salient than others as indexed by behavioral diagnosticity, gaze-fixation patterns and evoked-neural responses. However, because previous studies used unnatural stimuli, there is no evidence so far that the early encoding of a whole face in the human brain is based on the eyes or other facial features. To address this issue, scalp electroencephalogram (EEG) and eye gaze-fixations were recorded simultaneously in a gaze-contingent paradigm while observers viewed faces. We found that the N170 indexing the earliest face-sensitive response in the human brain was the largest when the fixation position is located around the nasion. Interestingly, for inverted faces, this optimal fixation position was more variable, but mainly clustered in the upper part of the visual field (around the mouth). These observations extend the findings of recent behavioral studies, suggesting that the early encoding of a face, as indexed by the N170, is not driven by the eyes per se, but rather arises from a general perceptual setting (upper-visual field advantage) coupled with the alignment of a face stimulus to a stored face template.

Oxytocin attenuates neural reactivity to masked threat cues from the eyes.

PubMed

Kanat, Manuela; Heinrichs, Markus; Schwarzwald, Ralf; Domes, Gregor

2015-01-01

The neuropeptide oxytocin has recently been shown to modulate covert attention shifts to emotional face cues and to improve discrimination of masked facial emotions. These results suggest that oxytocin modulates facial emotion processing at early perceptual stages prior to full evaluation of the emotional expression. Here, we used functional magnetic resonance imaging to examine whether oxytocin alters neural responses to backwardly masked angry and happy faces while controlling for attention to the eye vs the mouth region. Intranasal oxytocin administration reduced amygdala reactivity to masked emotions when attending to salient facial features, ie, the eyes of angry faces and the mouth of happy faces. In addition, oxytocin decreased neural responses within the fusiform gyrus and brain stem areas, as well as functional coupling between the amygdala and the fusiform gyrus specifically for threat cues from the eyes. Effects of oxytocin on brain activity were not attributable to differences in behavioral performance, as oxytocin had no impact on mere emotion detection. Our results suggest that oxytocin attenuates neural correlates of early arousal by threat signals from the eye region. As reduced threat sensitivity may increase the likelihood of engaging in social interactions, our findings may have important implications for clinical states of social anxiety.

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

PubMed

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

2015-01-01

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

Ultrawide-field Fluorescein Angiography for Evaluation of Diabetic Retinopathy

PubMed Central

Kong, Mingui; Lee, Mee Yon

2012-01-01

Purpose To investigate the advantages of ultrawide-field fluorescein angiography (FA) over the standard fundus examination in the evaluation of diabetic retinopathy (DR). Methods Ultrawide-field FAs were obtained in 118 eyes of 59 diabetic patients; 11 eyes with no DR, 71 eyes with nonproliferative diabetic retinopathy (NPDR), and 36 eyes with proliferative diabetic retinopathy (PDR), diagnosed by the standard method. The presence of peripheral abnormal lesions beyond the standard seven fields was examined. Results Ultrawide-field FA images demonstrated peripheral microaneurysms in six (54.5%) of 11 eyes with no DR and all eyes with moderate to severe NPDR and PDR. Peripheral retinal neovascularizations were detected in three (4.2%) of 71 eyes with NPDR and in 13 (36.1%) of 36 eyes with PDR. Peripheral vascular nonperfusion and vascular leakage were found in two-thirds of eyes with severe NPDR and PDR. Conclusions Ultrawide-field FA demonstrates peripheral lesions beyond standard fields, which can allow early detection and a close evaluation of DR. PMID:23204797

Spectral analysis of fundus autofluorescence pattern as a tool to detect early stages of degeneration in the retina and retinal pigment epithelium.

PubMed

Feldman, Tatiana B; Yakovleva, Marina A; Larichev, Andrey V; Arbukhanova, Patimat M; Radchenko, Alexandra Sh; Borzenok, Sergey A; Kuzmin, Vladimir A; Ostrovsky, Mikhail A

2018-05-22

The aim of this work is the determination of quantitative diagnostic criteria based on the spectral characteristics of fundus autofluorescence to detect early stages of degeneration in the retina and retinal pigment epithelium (RPE). RPE cell suspension samples were obtained from the cadaver eyes with and without signs of age-related macular degeneration (AMD). Fluorescence analysis at an excitation wavelength of 488 nm was performed. The fluorescence lifetimes of lipofuscin-granule fluorophores were measured by counting time-correlated photon method. Comparative analysis of fluorescence spectra of RPE cell suspensions from the cadaver eyes with and without signs of AMD showed a significant difference in fluorescence intensity at 530-580 nm in response to fluorescence excitation at 488 nm. It was notably higher in eyes with visual pathology than in normal eyes regardless of the age of the eye donor. Measurements of fluorescence lifetimes of lipofuscin fluorophores showed that the contribution of photooxidation and photodegradation products of bisretinoids to the total fluorescence at 530-580 nm of RPE cell suspensions was greater in eyes with visual pathology than in normal eyes. Because photooxidation and photodegradation products of bisretinoids are markers of photodestructive processes, which can cause RPE cell death and initiate degenerative processes in the retina, quantitative determination of increases in these bisretinoid products in lipofuscin granules may be used to establish quantitative diagnostic criteria for degenerative processes in the retina and RPE.

Eye coding mechanisms in early human face event-related potentials.

PubMed

Rousselet, Guillaume A; Ince, Robin A A; van Rijsbergen, Nicola J; Schyns, Philippe G

2014-11-10

In humans, the N170 event-related potential (ERP) is an integrated measure of cortical activity that varies in amplitude and latency across trials. Researchers often conjecture that N170 variations reflect cortical mechanisms of stimulus coding for recognition. Here, to settle the conjecture and understand cortical information processing mechanisms, we unraveled the coding function of N170 latency and amplitude variations in possibly the simplest socially important natural visual task: face detection. On each experimental trial, 16 observers saw face and noise pictures sparsely sampled with small Gaussian apertures. Reverse-correlation methods coupled with information theory revealed that the presence of the eye specifically covaries with behavioral and neural measurements: the left eye strongly modulates reaction times and lateral electrodes represent mainly the presence of the contralateral eye during the rising part of the N170, with maximum sensitivity before the N170 peak. Furthermore, single-trial N170 latencies code more about the presence of the contralateral eye than N170 amplitudes and early latencies are associated with faster reaction times. The absence of these effects in control images that did not contain a face refutes alternative accounts based on retinal biases or allocation of attention to the eye location on the face. We conclude that the rising part of the N170, roughly 120-170 ms post-stimulus, is a critical time-window in human face processing mechanisms, reflecting predominantly, in a face detection task, the encoding of a single feature: the contralateral eye. © 2014 ARVO.

Studies shed light on youth sex and drinking. Parents and teens don't see eye to eye.

PubMed

2004-01-01

Researchers looking into early sexual behavior and attitudes about sex among youths have found that alcohol use does play a role in sexual initiation, and that children have different attitudes about sexual behavior even as young as preteens.

How to Keep Your Sight for Life

MedlinePlus

... through early detection and treatment of eye diseases. This year marks the 40th anniversary of the National Eye ... 28, according to one recent NEI-funded study. This figure is projected to reach 5.5 million by the year 2020. Low vision and blindness increase significantly with ...

Eye Movement Desensitization and Reprocessing: A Critical Analysis.

ERIC Educational Resources Information Center

Erwin, Terry McVannel

Since Shapiro's introduction of Eye Movement Desensitization and Reprocessing (EMDR) in 1989, it has been a highly controversial therapeutic technique. Critical reviews of Shapiro's initial study have highlighted many methodological shortcomings in her work. And early empirical research that followed Shapiro's original study has been criticized…

Automated cross-modal mapping in robotic eye/hand systems using plastic radial basis function networks

NASA Astrophysics Data System (ADS)

Meng, Qinggang; Lee, M. H.

2007-03-01

Advanced autonomous artificial systems will need incremental learning and adaptive abilities similar to those seen in humans. Knowledge from biology, psychology and neuroscience is now inspiring new approaches for systems that have sensory-motor capabilities and operate in complex environments. Eye/hand coordination is an important cross-modal cognitive function, and is also typical of many of the other coordinations that must be involved in the control and operation of embodied intelligent systems. This paper examines a biologically inspired approach for incrementally constructing compact mapping networks for eye/hand coordination. We present a simplified node-decoupled extended Kalman filter for radial basis function networks, and compare this with other learning algorithms. An experimental system consisting of a robot arm and a pan-and-tilt head with a colour camera is used to produce results and test the algorithms in this paper. We also present three approaches for adapting to structural changes during eye/hand coordination tasks, and the robustness of the algorithms under noise are investigated. The learning and adaptation approaches in this paper have similarities with current ideas about neural growth in the brains of humans and animals during tool-use, and infants during early cognitive development.

Drosophila Lin-52 Acts in Opposition to Repressive Components of the Myb-MuvB/dREAM Complex

PubMed Central

Lewis, Peter W.; Sahoo, Debashis; Geng, Cuiyun; Bell, Maren

2012-01-01

The Drosophila melanogaster Myb-MuvB/dREAM complex (MMB/dREAM) participates in both the activation and repression of developmentally regulated genes and origins of DNA replication. Mutants in MMB subunits exhibit diverse phenotypes, including lethality, eye defects, reduced fecundity, and sterility. Here, we used P-element excision to generate mutations in lin-52, which encodes the smallest subunit of the MMB/dREAM complex. lin-52 is required for viability, as null mutants die prior to pupariation. The generation of somatic and germ line mutant clones indicates that lin-52 is required for adult eye development and for early embryogenesis via maternal effects. Interestingly, the maternal-effect embryonic lethality, larval lethality, and adult eye defects could be suppressed by mutations in other subunits of the MMB/dREAM complex. These results suggest that a partial MMB/dREAM complex is responsible for the lethality and eye defects of lin-52 mutants. Furthermore, these findings support a model in which the Lin-52 and Myb proteins counteract the repressive activities of the other members of the MMB/dREAM complex at specific genomic loci in a developmentally controlled manner. PMID:22688510

Eye-rotation-induced spatial reorganization of horizontal connections in field 17 of the cat cortex.

PubMed

Shkorbatova, P Yu; Alekseenko, S V

2006-06-01

Six cats with rotation of one or both eyes (strabismus) produced surgically in the early postnatal period demonstrated torsional deviation of the eyes by 10-20 degrees in addition to the rotation. The spatial distribution of retrograde labeled neurons in field 17 was studied by microiontophoretic administration of horseradish peroxidase into individual cortical columns in fields 17 and 18. These studies showed that rotation of the eyes increased the extent of horizontal neuronal connections in field 17 along the projection of the vertical meridian of the field of vision. It is suggested that this reorganization of neuronal connections may support functional changes compensating for eye rotation, as described in the literature.

Epileptic encephalopathy in a girl with an interstitial deletion of Xp22 comprising promoter and exon 1 of the CDKL5 gene.

PubMed

Bahi-Buisson, Nadia; Girard, Benoit; Gautier, Agnes; Nectoux, Juliette; Fichou, Yann; Saillour, Yoann; Poirier, Karine; Chelly, Jamel; Bienvenu, Thierry

2010-01-05

We report a 2-year-old girl with early onset seizures variant of Rett syndrome with a deletion at Xp22 detected by multiplex ligation-dependent probe amplification (MLPA) technique. This patient presented with tonic seizures at 7 days of life. Subsequently, she developed infantile spasms at three months and finally refractory myoclonic epilepsy. She demonstrated severe encephalopathy with hypotonia, deceleration of head growth, with eye gaze but limited eye pursuit, no language, limited hand use, and intermittent hand stereotypies. This combination of clinical features, suggestive of early onset variant of Rett syndrome led us to screen the CDKL5 gene. In a first step, screening of the whole coding sequence of the CDKL5 gene revealed no point mutations. In a second step, we searched gross rearrangements by MLPA and identified a microdeletion affecting both the promoter and exon 1 in CDKL5. Subsequent analysis on a Nimblegen HD2 microarray confirmed a deletion of approximately 300 kb at Xp22, including the BEND2, SCML2, and CDKL5 genes. In conclusion, our report suggests that searching for large rearrangements in CDKL5 should be considered in girls with early onset seizures and Rett-like features. (c) 2009 Wiley-Liss, Inc.

Characteristics of incident geographic atrophy in the complications of age-related macular degeneration prevention trial.

PubMed

Brader, Hilary Smolen; Ying, Gui-Shuang; Martin, E Revell; Maguire, Maureen G

2013-09-01

To characterize the size, location, conformation, and features of incident geographic atrophy (GA) as detected by annual stereoscopic color photographs and fluorescein angiograms (FAs). Retrospective cohort study within a larger clinical trial. Patients with bilateral large drusen in whom GA developed during the course of the Complications of Age-related Macular Degeneration Prevention Trial (CAPT). Annual stereoscopic color photographs and FAs were reviewed from 114 CAPT patients in whom GA developed in the untreated eye during 5 to 6 years of follow-up. Geographic atrophy was defined according to the Revised GA Criteria for identifying early GA.(23) Color-optimized fundus photographs were viewed concurrently with the FAs during grading. Size and distance from the fovea of individual GA lesions, number of areas of atrophy, and change in visual acuity (VA) when GA first developed in an eye. At presentation, the median total GA area was 0.26 mm(2) (0.1 disc area). Geographic atrophy presented as a single lesion in 89 (78%) eyes. The median distance from the fovea was 395 μm. Twenty percent of incident GA lesions were subfoveal and an additional 18% were within 250 μm of the foveal center. Development of GA was associated with a mean decrease of 7 letters from the baseline VA level compared with 1 letter among matched early age-related macular degeneration eyes without GA. Geographic atrophy that formed in areas previously occupied by drusenoid pigment epithelial detachments on average were larger (0.53 vs. 0.20 mm(2); P = 0.0001), were more central (50 vs. 500 μm from the center of the fovea; P<0.0001), and were associated with significantly worse visual outcome (20/50 vs. 20/25; P = 0.0003) than GA with other drusen types as precursors. Incident GA most often appears on color fundus photographs and FAs as a small, singular, parafoveal lesion, although a large minority of lesions are subfoveal or multifocal at initial detection. The characteristics of incident GA vary with precursor drusen types. These data can facilitate design of future clinical trials of therapies for GA. The author(s) have no proprietary or commercial interest in any materials discussed in this article. Copyright © 2013 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Automated radial basis function neural network based image classification system for diabetic retinopathy detection in retinal images

NASA Astrophysics Data System (ADS)

Anitha, J.; Vijila, C. Kezi Selva; Hemanth, D. Jude

2010-02-01

Diabetic retinopathy (DR) is a chronic eye disease for which early detection is highly essential to avoid any fatal results. Image processing of retinal images emerge as a feasible tool for this early diagnosis. Digital image processing techniques involve image classification which is a significant technique to detect the abnormality in the eye. Various automated classification systems have been developed in the recent years but most of them lack high classification accuracy. Artificial neural networks are the widely preferred artificial intelligence technique since it yields superior results in terms of classification accuracy. In this work, Radial Basis function (RBF) neural network based bi-level classification system is proposed to differentiate abnormal DR Images and normal retinal images. The results are analyzed in terms of classification accuracy, sensitivity and specificity. A comparative analysis is performed with the results of the probabilistic classifier namely Bayesian classifier to show the superior nature of neural classifier. Experimental results show promising results for the neural classifier in terms of the performance measures.

Infant Neural Sensitivity to Dynamic Eye Gaze Relates to Quality of Parent-Infant Interaction at 7-Months in Infants at Risk for Autism

ERIC Educational Resources Information Center

Elsabbagh, Mayada; Bruno, Ruth; Wan, Ming Wai; Charman, Tony; Johnson, Mark H.; Green, Jonathan

2015-01-01

Links between brain function measures and quality of parent-child interactions within the early developmental period have been investigated in typical and atypical development. We examined such links in a group of 104 infants with and without a family history for autism in the first year of life. Our findings suggest robust associations between…

Intraocular (Uveal) Melanoma Symptoms, Tests, Prognosis, and Stages (PDQ®)—Patient Version

Cancer.gov

Intraocular melanoma is a rare cancer that forms from cells that make melanin in the eye. It is the most common eye cancer in adults and may not cause early signs or symptoms. Find out risk factors, tests to diagnose, prognosis, and staging for intraocular melanoma.

75 FR 10993 - Save Your Vision Week, 2010

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-10

... Your Vision Week, 2010 By the President of the United States of America A Proclamation While many Americans are fortunate to have healthy eyes, millions are affected by low vision or blindness. Maintaining good vision requires early diagnosis and timely treatment of eye conditions. Save Your Vision Week is a...

ERPs and Eye Movements Reflect Atypical Visual Perception in Pervasive Developmental Disorder

ERIC Educational Resources Information Center

Kemner, Chantal; van Engeland, Herman

2006-01-01

Many studies of eye tracking or event-related brain potentials (ERPs) in subjects with Pervasive Developmental Disorder (PDD) have yielded inconsistent results on attentional processing. However, recent studies have indicated that there are specific abnormalities in early processing that are probably related to perception. ERP amplitudes in…

Oculomotor Exploration of Impossible Figures in Early Infancy

ERIC Educational Resources Information Center

Shuwairi, Sarah M.; Johnson, Scott P.

2013-01-01

Previous studies have revealed that young infants can distinguish between displays of possible or impossible figures, which may require detection of inconsistent depth relations among local line junctions that disrupt global object configurations. Here, we used an eye-tracking paradigm to record eye movements in young infants during an object…

Integrated Eye Tracking and Neural Monitoring for Enhanced Assessment of Mild TBI

DTIC Science & Technology

2016-04-01

but these delays are nearing resolution and we anticipate the initiation of the neuroimaging portion of the study early in Year 3. The fMRI task...resonance imagining ( fMRI ) and diffusion tensor imaging (DTI) to characterize the extent of functional cortical recruitment and white matter injury...respectively. The inclusion of fMRI and DTI will provide an objective basis for cross-validating the EEG and eye tracking system. Both the EEG and eye

Pioneers of eye movement research

PubMed Central

Wade, Nicholas J

2010-01-01

Recent advances in the technology affording eye movement recordings carry the risk of neglecting past achievements. Without the assistance of this modern armoury, great strides were made in describing the ways the eyes move. For Aristotle the fundamental features of eye movements were binocular, and he described the combined functions of the eyes. This was later given support using simple procedures like placing a finger over the eyelid of the closed eye and culminated in Hering's law of equal innervation. However, the overriding concern in the 19th century was with eye position rather than eye movements. Appreciating discontinuities of eye movements arose from studies of vertigo. The characteristics of nystagmus were recorded before those of saccades and fixations. Eye movements during reading were described by Hering and by Lamare in 1879; both used similar techniques of listening to sounds made during contractions of the extraocular muscles. Photographic records of eye movements during reading were made by Dodge early in the 20th century, and this stimulated research using a wider array of patterns. In the mid-20th century attention shifted to the stability of the eyes during fixation, with the emphasis on involuntary movements. The contributions of pioneers from Aristotle to Yarbus are outlined. PMID:23396982

Greater Pupil Size in Response to Emotional Faces as an Early Marker of Social-Communicative Difficulties in Infants at High Risk for Autism

PubMed Central

Wagner, Jennifer B.; Luyster, Rhiannon J.; Tager-Flusberg, Helen; Nelson, Charles A.

2016-01-01

When scanning faces, individuals with autism spectrum disorder (ASD) have shown reduced visual attention (e.g., less time on eyes) and atypical autonomic responses (e.g., heightened arousal). To understand how these differences might explain sub-clinical variability in social functioning, 9-month-olds, with or without a family history of ASD, viewed emotionally-expressive faces, and gaze and pupil diameter (a measure of autonomic activation) were recorded using eye-tracking. Infants at high-risk for ASD with no subsequent clinical diagnosis (HRA-) and low-risk controls (LRC) showed similar face scanning and attention to eyes and mouth. Attention was overall greater to eyes than mouth, but this varied as a function of the emotion presented. HRA- showed significantly larger pupil size than LRC. Correlations between scanning at 9 months, pupil size at 9 months, and 18-month social-communicative behavior, revealed positive associations between pupil size and attention to both face and eyes at 9 months in LRC, and a negative association between 9-month pupil size and 18-month social-communicative behavior in HRA-. The present findings point to heightened autonomic arousal in HRA-. Further, with greater arousal relating to worse social-communicative functioning at 18 months, this work points to a mechanism by which unaffected siblings might develop atypical social behavior. PMID:27616938

Greater Pupil Size in Response to Emotional Faces as an Early Marker of Social-Communicative Difficulties in Infants at High Risk for Autism.

PubMed

Wagner, Jennifer B; Luyster, Rhiannon J; Tager-Flusberg, Helen; Nelson, Charles A

2016-01-01

When scanning faces, individuals with autism spectrum disorder (ASD) have shown reduced visual attention (e.g., less time on eyes) and atypical autonomic responses (e.g., heightened arousal). To understand how these differences might explain sub-clinical variability in social functioning, 9-month-olds, with or without a family history of ASD, viewed emotionally-expressive faces, and gaze and pupil diameter (a measure of autonomic activation) were recorded using eye-tracking. Infants at high-risk for ASD with no subsequent clinical diagnosis (HRA-) and low-risk controls (LRC) showed similar face scanning and attention to eyes and mouth. Attention was overall greater to eyes than mouth, but this varied as a function of the emotion presented. HRA- showed significantly larger pupil size than LRC. Correlations between scanning at 9 months, pupil size at 9 months, and 18-month social-communicative behavior, revealed positive associations between pupil size and attention to both face and eyes at 9 months in LRC, and a negative association between 9-month pupil size and 18-month social-communicative behavior in HRA-. The present findings point to heightened autonomic arousal in HRA-. Further, with greater arousal relating to worse social-communicative functioning at 18 months, this work points to a mechanism by which unaffected siblings might develop atypical social behavior.

Short-Term Moderately Elevated Intraocular Pressure Is Associated With Elevated Scotopic Electroretinogram Responses

PubMed Central

Choh, Vivian; Gurdita, Akshay; Tan, Bingyao; Prasad, Ratna C.; Bizheva, Kostadinka; Joos, Karen M.

2016-01-01

Purpose Moderately elevated intraocular pressure (IOP) is a risk factor for open-angle glaucoma. Some patients suffer glaucoma despite clinically measured normal IOPs. Fluctuations in IOP may have a significant role since IOPs are higher during sleep and inversion activities. Controlled transient elevations of IOPs in rats over time lead to optic nerve structural changes that are similar to the early changes observed in constant chronic models of glaucoma. Because early intervention decreases glaucoma progression, this study was done to determine if early physiological changes to the retina could be detected with noninvasive electrophysiological and optical imaging tests during moderately elevated IOP. Methods Intraocular pressures were raised to moderately high levels (35 mm Hg) in one eye of Sprague-Dawley rats while the other (control) eye was untreated. One group of rats underwent scotopic threshold response (STR) and electroretinogram (ERG) testing, while another 3 groups underwent optical coherence tomography (OCT) imaging, Western blot, or histologic evaluation. Results The amplitudes of the STR and ERG responses in eyes with moderately elevated IOPs were enhanced compared to the values before IOP elevation, and compared to untreated contralateral eyes. Structural changes to the optic nerve also occurred during IOP elevation. Conclusions Although ischemic IOP elevations are well-known to globally reduce components of the scotopic ERG, acute elevation in rats to levels often observed in untreated glaucoma patients caused an increase in these parameters. Further exploration of these phenomena may be helpful in better understanding the mechanisms mediating early retinal changes during fluctuating or chronically elevated IOP. PMID:27100161

Pulsar perimetry in the diagnosis of early glaucoma.

PubMed

Zeppieri, Marco; Brusini, Paolo; Parisi, Lucia; Johnson, Chris A; Sampaolesi, Roberto; Salvetat, Maria Letizia

2010-01-01

To assess the ability of Pulsar perimetry (Pulsar) in detecting early glaucomatous visual field (VF) damage in comparison with Frequency Doubling Technology (FDT), Scanning Laser Polarimetry (SLP, GDx VCC), and Heidelberg Retina Tomography (HRT). Prospective observational cross-sectional case study. This multicenter study included: 87 ocular hypertensives (OHT); 67 glaucomatous optic neuropathy (GON) patients; 75 primary open-angle glaucoma (POAG) patients; and 90 normals. All patients underwent standard automated perimetry (SAP) HFA 30-2, Pulsar T30W, FDT N-30, HRT II, and GDx VCC. Area under Receiver Operating Characteristic Curves (AROCs) for discriminating between healthy and glaucomatous eyes and agreement among instruments were determined. The best parameters for Pulsar, FDT, HRT, and GDx were, respectively: loss variance square root; no. of areas with P< 5%; Cup-Shape-Measure; and Nerve Fiber Indicator (NFI). In detecting POAG eyes, Pulsar (AROC, 0.90) appeared comparable with FDT (0.89) and significantly better than HRT (0.82) and GDx (0.79). For GON, Pulsar ability (0.74) was higher than GDx (0.69) and lower than FDT (0.80) and HRT (0.83). The agreement among instruments ranged from 0.12 to 0.56. Pulsar test duration was significantly shorter than SAP and FDT (P< .001). Pulsar T30W test is a rapid and easy perimetric method, showing higher sensitivity than SAP in detecting early glaucomatous VF loss. Its diagnostic ability is good for detecting early perimetric POAG eyes and fair for GON eyes. Pulsar performance was comparable with FDT, HRT, and GDx, even if the agreement between instruments was poor to fair. Copyright 2010 Elsevier Inc. All rights reserved.

Sunlight exposure, pigmentation, and incident age-related macular degeneration.

PubMed

Klein, Barbara E K; Howard, Kerri P; Iyengar, Sudha K; Sivakumaran, Theru A; Meyers, Kristin J; Cruickshanks, Karen J; Klein, Ronald

2014-08-14

Examine potential effects of sunlight exposure, hair color, eye color, and selected gene single-nucleotide polymorphisms (SNPs) on incidence of AMD. Subjects participated in up to five examinations over a 20-year period. Eye color, self-reported hair color as a teenager, and sunlight exposure were ascertained at the baseline examination. Presence and severity of AMD and its lesions were determined via fundus photographs. Genetic data were available on a subset of participants. The SNPs CFH Y402H rs1061170 and ARMS2 A69S rs10490924 were used to analyze genetic risk of AMD; OCA2 rs4778241 and HERC2 rs12913832 represented genetic determinants of eye color. Incidence of early AMD was higher in blond/red-haired persons compared with brown/black-haired persons (hazard ratio [HR] 1.25, P = 0.02) and in persons with high sun exposure in their thirties (HR 1.41, P = 0.02). However, neither was significant after adjustment for multiple comparisons. Eye (HR 1.36, P = 0.006) and hair color (HR 1.42, P = 0.003) were associated with incidence of any retinal pigmentary abnormalities (RPAs). Both remained significant after adjustment for multiple comparisons. Neither presence of alleles for light-colored eyes nor those associated with high risk of late AMD altered the association of eye or hair color with early AMD. None of the characteristics studied were significantly associated with late AMD. Modest associations of eye color, hair color, and HERC2 genotype with any RPAs were found. Genes for AMD did not affect these associations. Eye color phenotype was more strongly associated with outcomes than HERC2 or OCA2 genotype. Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.

Structure and function of a compound eye, more than half a billion years old.

PubMed

Schoenemann, Brigitte; Pärnaste, Helje; Clarkson, Euan N K

2017-12-19

Until now, the fossil record has not been capable of revealing any details of the mechanisms of complex vision at the beginning of metazoan evolution. Here, we describe functional units, at a cellular level, of a compound eye from the base of the Cambrian, more than half a billion years old. Remains of early Cambrian arthropods showed the external lattices of enormous compound eyes, but not the internal structures or anything about how those compound eyes may have functioned. In a phosphatized trilobite eye from the lower Cambrian of the Baltic, we found lithified remnants of cellular systems, typical of a modern focal apposition eye, similar to those of a bee or dragonfly. This shows that sophisticated eyes already existed at the beginning of the fossil record of higher organisms, while the differences between the ancient system and the internal structures of a modern apposition compound eye open important insights into the evolution of vision. Copyright © 2017 the Author(s). Published by PNAS.

Application of deep learning in the identification of TAO

NASA Astrophysics Data System (ADS)

Wu, Cong; Jin, Jicheng

2018-03-01

Thyroid associated ophthalmopathy (TAO) is one of the most common orbital disease, it can be easily detected by the human eye in the late onset due to obvious changes in extraocular muscles. But in the early stage, it is not easy to be distinguish by doctors with eye because of subtle changes in extraocular muscles, so it is a good way to use the computer's ability to assist doctors to pre-diagnosis of TAO for follow-up treatment. In this paper, according to the routine diagnosis process of doctors, a comprehensive detection system network is proposed. The network consists of three different convolutional neural subnetwork, corresponding to three bitmaps of eye CT images .Finally, the output of three subnetwork are combined to generate final diagnostic result by the majority vote. Through the experiment, the detection system, whose recognition rata is 94.87%, has a good ability to identify the characteristics of TAO, can assist the doctor in the early diagnosis of TAO in a certain extent, so as to help early patients get timely treatment.

Binocular visual training to promote recovery from monocular deprivation.

PubMed

Murphy, Kathryn M; Roumeliotis, Grayson; Williams, Kate; Beston, Brett R; Jones, David G

2015-01-08

Abnormal early visual experience often leads to poor vision, a condition called amblyopia. Two recent approaches to treating amblyopia include binocular therapies and intensive visual training. These reflect the emerging view that amblyopia is a binocular deficit caused by increased neural noise and poor signal-in-noise integration. Most perceptual learning studies have used monocular training; however, a recent study has shown that binocular training is effective for improving acuity in adult human amblyopes. We used an animal model of amblyopia, based on monocular deprivation, to compare the effect of binocular training either during or after the critical period for ocular dominance plasticity (early binocular training vs. late binocular training). We used a high-contrast, orientation-in-noise stimulus to drive the visual cortex because neurophysiological findings suggest that binocular training may allow the nondeprived eye to teach the deprived eye's circuits to function. We found that both early and late binocular training promoted good visual recovery. Surprisingly, we found that monocular deprivation caused a permanent deficit in the vision of both eyes, which became evident only as a sleeper effect following many weeks of visual training. © 2015 ARVO.

Corneal abrasion and alkali burn secondary to automobile air bag inflation

PubMed Central

Scarlett, Angela; Gee, Paul

2007-01-01

A 59‐year‐old woman self presented to the emergency department with a painful right eye following a motor vehicle accident. She had reduced visual acuity and the eye had an alkaline pH with complete corneal uptake of fluorescein. Diagnosis of corneal abrasion and alkali burn to her right eye secondary to inflation of a driver's automobile airbag was made. The eye was irrigated with normal saline. Such injuries, although rare, can easily be identified within the emergency department by the history of exposure, evidence of facial injuries or burns, and an alkaline pH in the inferior cul‐de‐sac of the eye. Early detection and management with ophthalmology review is therefore imperative to prevent irreversible visual impairment. PMID:17901284

Eye disorders in newborn infants (excluding retinopathy of prematurity).

PubMed

Wan, Michael J; VanderVeen, Deborah K

2015-05-01

A screening eye examination is an essential part of the newborn assessment. The detection of many ocular disorders in newborn infants can be achieved through careful observation of the infant's visual behaviour and the use of a direct ophthalmoscope to assess the ocular structures and check the red reflex. Early diagnosis and subspecialty referral can have a critical impact on the prognosis for many ocular conditions, including potentially blinding but treatable conditions such as congenital cataracts, life-threatening malignancies such as retinoblastoma and harbingers of disease elsewhere such as sporadic aniridia and its association with the development of Wilms tumour. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Automated detection of preserved photoreceptor on optical coherence tomography in choroideremia based on machine learning.

PubMed

Wang, Zhuo; Camino, Acner; Hagag, Ahmed M; Wang, Jie; Weleber, Richard G; Yang, Paul; Pennesi, Mark E; Huang, David; Li, Dengwang; Jia, Yali

2018-05-01

Optical coherence tomography (OCT) can demonstrate early deterioration of the photoreceptor integrity caused by inherited retinal degeneration diseases (IRDs). A machine learning method based on random forests was developed to automatically detect continuous areas of preserved ellipsoid zone structure (an easily recognizable part of the photoreceptors on OCT) in 16 eyes of patients with choroideremia (a type of IRD). Pseudopodial extensions protruding from the preserved ellipsoid zone areas are detected separately by a local active contour routine. The algorithm is implemented on en face images with minimum segmentation requirements, only needing delineation of the Bruch's membrane, thus evading the inaccuracies and technical challenges associated with automatic segmentation of the ellipsoid zone in eyes with severe retinal degeneration. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Developmental visual perception deficits with no indications of prosopagnosia in a child with abnormal eye movements.

PubMed

Gilaie-Dotan, Sharon; Doron, Ravid

2017-06-01

Visual categories are associated with eccentricity biases in high-order visual cortex: Faces and reading with foveally-biased regions, while common objects and space with mid- and peripherally-biased regions. As face perception and reading are among the most challenging human visual skills, and are often regarded as the peak achievements of a distributed neural network supporting common objects perception, it is unclear why objects, which also rely on foveal vision to be processed, are associated with mid-peripheral rather than with a foveal bias. Here, we studied BN, a 9 y.o. boy who has normal basic-level vision, abnormal (limited) oculomotor pursuit and saccades, and shows developmental object and contour integration deficits but with no indication of prosopagnosia. Although we cannot infer causation from the data presented here, we suggest that normal pursuit and saccades could be critical for the development of contour integration and object perception. While faces and perhaps reading, when fixated upon, take up a small portion of central visual field and require only small eye movements to be properly processed, common objects typically prevail in mid-peripheral visual field and rely on longer-distance voluntary eye movements as saccades to be brought to fixation. While retinal information feeds into early visual cortex in an eccentricity orderly manner, we hypothesize that propagation of non-foveal information to mid and high-order visual cortex critically relies on circuitry involving eye movements. Limited or atypical eye movements, as in the case of BN, may hinder normal information flow to mid-eccentricity biased high-order visual cortex, adversely affecting its development and consequently inducing visual perceptual deficits predominantly for categories associated with these regions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Integrated Eye Tracking and Neural Monitoring for Enhanced Assessment of Mild TBI

DTIC Science & Technology

2016-04-01

and we anticipate the initiation of the neuroimaging portion of the study early in Year 3. The fMRI task has been completed and is in beta testing...neurocognitive test battery, and self-report measures of cognitive efficacy. We will also include functional magnetic resonance imagining ( fMRI ) and... fMRI and DTI will provide an objective basis for cross-validating the EEG and eye tracking system. Both the EEG and eye tracking data will be

[Fatal air embolism during open eye surgery].

PubMed

Dermigny, F; Daelman, F; Guinot, P-G; Hubert, V; Jezraoui, P; Thomas, F; Milazzo, S; Dupont, H

2008-10-01

Gas embolism is well known for a specific subset of surgical interventions. Prevention and early detection are the main objectives of the anesthetic and surgical team. However, it may exceptionally occur during eye surgery with dramatic outcomes. We report the case of a 51-year-old man, ASA physical status 1, who presented a cardiac arrest during an open eye surgery for the extraction of a foreign body with intraocular air injection. Multiple organ failure has not been improved by hyperbaric oxygen therapy and the outcome was fatal.

Comparison of the Early Clinical Outcomes between Combined Small-Incision Lenticule Extraction and Collagen Cross-Linking versus SMILE for Myopia.

PubMed

Ng, Alex L K; Chan, Tommy C Y; Cheng, George P M; Jhanji, Vishal; Ye, Cong; Woo, Victor C P; Lai, Jimmy S M

2016-01-01

Background. To compare the early outcome of combined SMILE and collagen crosslinking (SMILE Xtra) with SMILE. Method. Prospective, comparative interventional study of 21 eyes receiving SMILE Xtra using a low energy protocol and 32 control eyes receiving SMILE only. The outcomes were compared at 1, 3, and 6 months postoperatively. Results. Both groups had myopia with spherical equivalent refraction (SEQ) > 4.00 D. The SMILE Xtra group had thinner preoperative central corneal thickness and residual stromal bed thickness (p < 0.021). At 6 months, no eyes lost more than 1 line in corrected distance visual acuity. The safety index was 0.96 ± 0.06 and 1.00 ± 0.00 in SMILE Xtra and control, respectively (p < 0.001). 89% and 94% of eyes were within ±0.50 D of target refraction, respectively, with the mean error in SEQ correction being -0.17 ± 0.26 D for SMILE Xtra and +0.03 ± 0.25 D for control (p = 0.021). The efficacy index was 0.88 ± 0.13 and 0.97 ± 0.06, respectively (p = 0.005). Conclusion. SMILE Xtra had good overall safety profile and predictability at 6 months. However, when compared with control, the safety index and efficacy index were statistically significantly lower in the early postoperative period.

Impaired eye movements in presymptomatic spinocerebellar ataxia type 6.

PubMed

Christova, Peka; Anderson, John H; Gomez, Christopher M

2008-04-01

Early detection of impaired neurological function in neurodegenerative diseases may aid in understanding disease pathogenesis and timing of therapeutic trials. To identify early abnormalities of ocular motor function in individuals who have the spinocerebellar ataxia type 6 (SCA6) gene (CACNA1A) but no clinical symptoms. Physiological techniques were used to record and analyze eye movements and postural sway. Four presymptomatic and 5 ataxic patients with SCA6, genetically identified, and 10 healthy controls. Presymptomatic individuals had normal postural sway but definite ocular motor abnormalities. Two had a low-amplitude horizontal gaze-evoked nystagmus, 1 of whom had a significantly decreased eye velocity for upward saccades and an abnormal frequency of square-wave jerks. Another had abnormal square-wave jerks and a fourth had a reduced gain for pursuit tracking. Not all of the presymptomatic patients had the same findings, but a multivariate analysis discriminated the presymptomatic patients, as a group, from healthy controls and the ataxic patients. Among the earliest functional deficits in SCA6 are eye movement abnormalities, including impaired saccade velocity, saccade metrics, and pursuit gain. This suggests that early functional impairments are caused by cellular dysfunction and/or loss in the posterior cerebellar vermis and flocculus. These findings might help to determine the timing of a treatment and to define variables that could be used as outcome measures for the efficacy of therapeutic trials.

PRK vs LASEK vs Epi-LASIK: a comparison of corneal haze, postoperative pain and visual recovery in moderate to high myopia.

PubMed

Reilly, C D; Panday, V; Lazos, V; Mittelstaedt, B R

2010-01-01

The field of refractive surgery continues to evolve amid continued concerns as to which surgical technique minimizes the risk of inducing ectasia. To compare clinical outcomes between PRK, LASEK and Epi-LASIK in moderately to highly myopic eyes (-4.00 D to -8.00 D). A retrospective chart review of 100 PRK eyes, 100 LASEK eyes (with alcohol) and 97 Epi-LASIK eyes was performed. Post-operative pain, uncorrected visual acuity, and corneal haze data was recorded and analyzed at post-op days 1, 4 and 7 and at post-op months 1, 3, 6 and 12. In all groups surgical corrections ranged from -4.00 D to -8.00 D. There was less pain associated with the epi-LASIK procedure especially early (post-op days 1 and 4). Visual recovery was superior within the PRK group during the first post-operative week but by post-op week 4 all three were equal. Haze scores were similar but a trend for less haze was demonstrated with epi-LASIK at 6 and 12 months. Epi-LASIK has a slight advantage over PRK and LASEK early on in the post-op course with regards to pain. Visual recovery is similar by 4 weeks and is better with PRK early. In addition, epi-LASIK trends toward less significant haze. © Nepal Ophthalmic Society.

The Rat With Oxygen-Induced Retinopathy Is Myopic With Low Retinal Dopamine

PubMed Central

Zhang, Nan; Favazza, Tara L.; Baglieri, Anna Maria; Benador, Ilan Y.; Noonan, Emily R.; Fulton, Anne B.; Hansen, Ronald M.; Iuvone, P. Michael; Akula, James D.

2013-01-01

Purpose. Dopamine (DA) is a neurotransmitter implicated both in modulating neural retinal signals and in eye growth. Therefore, it may participate in the pathogenesis of the most common clinical sequelae of retinopathy of prematurity (ROP), visual dysfunction and myopia. Paradoxically, in ROP myopia the eye is usually small. The eye of the rat with oxygen-induced retinopathy (OIR) is characterized by retinal dysfunction and short axial length. There have been several investigations of the early maturation of DA in rat retina, but little at older ages, and not in the OIR rat. Therefore, DA, retinal function, and refractive state were investigated in the OIR rat. Methods. In one set of rats, the development of dopaminergic (DAergic) networks was evaluated in retinal cross-sections from rats aged 14 to 120 days using antibodies against tyrosine hydroxylase (TH, the rate-limiting enzyme in the biosynthesis of DA). In another set of rats, retinoscopy was used to evaluate spherical equivalent (SE), electoretinography (ERG) was used to evaluate retinal function, and high-pressure liquid chromatography (HPLC) was used to evaluate retinal contents of DA, its precursor levodopamine (DOPA), and its primary metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). Results. The normally rapid postnatal ramification of DAergic neurons was disrupted in OIR rats. Retinoscopy revealed that OIR rats were relatively myopic. In the same eyes, ERG confirmed retinal dysfunction in OIR. HPLC of those eyes' retinae confirmed low DA. Regression analysis indicated that DA metabolism (evaluated by the ratio of DOPAC to DA) was an important additional predictor of myopia beyond OIR. Conclusions. The OIR rat is the first known animal model of myopia in which the eye is smaller than normal. Dopamine may modulate, or fail to modulate, neural activity in the OIR eye, and thus contribute to this peculiar myopia. PMID:24168993

The rat with oxygen-induced retinopathy is myopic with low retinal dopamine.

PubMed

Zhang, Nan; Favazza, Tara L; Baglieri, Anna Maria; Benador, Ilan Y; Noonan, Emily R; Fulton, Anne B; Hansen, Ronald M; Iuvone, P Michael; Akula, James D

2013-12-19

Dopamine (DA) is a neurotransmitter implicated both in modulating neural retinal signals and in eye growth. Therefore, it may participate in the pathogenesis of the most common clinical sequelae of retinopathy of prematurity (ROP), visual dysfunction and myopia. Paradoxically, in ROP myopia the eye is usually small. The eye of the rat with oxygen-induced retinopathy (OIR) is characterized by retinal dysfunction and short axial length. There have been several investigations of the early maturation of DA in rat retina, but little at older ages, and not in the OIR rat. Therefore, DA, retinal function, and refractive state were investigated in the OIR rat. In one set of rats, the development of dopaminergic (DAergic) networks was evaluated in retinal cross-sections from rats aged 14 to 120 days using antibodies against tyrosine hydroxylase (TH, the rate-limiting enzyme in the biosynthesis of DA). In another set of rats, retinoscopy was used to evaluate spherical equivalent (SE), electoretinography (ERG) was used to evaluate retinal function, and high-pressure liquid chromatography (HPLC) was used to evaluate retinal contents of DA, its precursor levodopamine (DOPA), and its primary metabolite 3,4-dihydroxyphenylacetic acid (DOPAC). The normally rapid postnatal ramification of DAergic neurons was disrupted in OIR rats. Retinoscopy revealed that OIR rats were relatively myopic. In the same eyes, ERG confirmed retinal dysfunction in OIR. HPLC of those eyes' retinae confirmed low DA. Regression analysis indicated that DA metabolism (evaluated by the ratio of DOPAC to DA) was an important additional predictor of myopia beyond OIR. The OIR rat is the first known animal model of myopia in which the eye is smaller than normal. Dopamine may modulate, or fail to modulate, neural activity in the OIR eye, and thus contribute to this peculiar myopia.

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss)

PubMed Central

Schultz, Irv; Brown, Kim H.; Nagler, James J.

2008-01-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 μg/kg/day BDE-47 and female trout continuously exposed for 60–77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two–three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring. PMID:18397801

Effect of parental exposure to trenbolone and the brominated flame retardant BDE-47 on fertility in rainbow trout (Oncorhynchus mykiss).

PubMed

Schultz, Irv; Brown, Kim H; Nagler, James J

2008-07-01

We exposed sexually maturing male rainbow trout (Oncorhynchus mykiss) to BDE-47 (a polybrominated diphenyl ether) and female rainbow trout to trenbolone (an anabolic steroid). Male trout were orally exposed for 17 days to 55 microg/kg/day BDE-47 and female trout continuously exposed for 60-77 days to a measured trenbolone water concentration of 35 ng/L. After the exposure, eggs and semen were collected and in vitro fertilization trials performed using a sperm:egg ratio of 300,000:1. In the BDE-47 study, eggs from control females were fertilized with semen from exposed males, while in the trenbolone study, eggs from exposed females were fertilized with semen from control males. All treatments were evaluated at two-three early developmental time-points representing first cleavage (0.5 day), embryonic keel (9 days), and eyed stages (19 days), respectively. The results indicated that BDE-47 exposure did not alter fertility as embryonic survival was similar between control and exposed groups. Trenbolone exposure also did not alter embryo survival. However, in the embryos fertilized with eggs from trenbolone exposed females, a noticeable delay in developmental progress was observed. On day 19 when eye development is normally complete, the majority of the embryos either lacked eyes or displayed under-developed eyes, in contrast to control embryos. This finding suggests steroidal androgen exposure in sexually maturing female rainbow trout can impact developmental timing of F1 offspring.

Early corneal nerve damage and recovery following small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK).

PubMed

Mohamed-Noriega, Karim; Riau, Andri K; Lwin, Nyein C; Chaurasia, Shyam S; Tan, Donald T; Mehta, Jodhbir S

2014-03-25

We compared early corneal nerve changes after small incision lenticule extraction (SMILE) and laser in situ keratomileusis (LASIK). A total of 12 rabbits underwent LASIK in one eye and SMILE in the fellow eye. Baseline and follow-up evaluations at 1, 2, and 4 weeks postoperatively were performed with in vivo confocal microscopy to evaluate 5 different areas within the treated zone: center, superior, inferior, nasal, and temporal. Cryosections of the corneas and whole mount of the extracted SMILE lenticules were analyzed with immunostaining of βIII-tubulin. One week after SMILE and LASIK, a decrease in nerve length and density was observed in all evaluated areas. A trend toward greater subbasal nerve length and density (SLD), more eyes with subbasal nerves (ESN), more eyes with subbasal nerves longer than 200 μm (SNL), and higher mean number of subbasal nerves by frame (NSN) in SMILE than in LASIK groups was observed at subsequent follow-up time points. Only the SMILE group showed a recovery of SLD, ESN, and NSN by week 4 (P > 0.05). A trend toward more eyes with sprouting subbasal nerves and greater mean number of sprouting nerves was observed in LASIK than in SMILE, indicating that more subbasal nerves were disrupted and undergoing regeneration after LASIK. Immunostaining at postoperative week 4 revealed a faster stromal nerve recovery in post-SMILE eyes compared to post-LASIK eyes. Our findings suggest that SMILE results in less nerve damage and faster nerve recovery than LASIK.

A Comparison of Patched HOTV Visual Acuity and Photoscreening

ERIC Educational Resources Information Center

Leman, Rachel; Clausen, Michelle M.; Bates, Janice; Stark, Lee; Arnold, Koni K.; Arnold, Robert W.

2006-01-01

Early detection of significant vision problems in children is a high priority for pediatricians and school nurses. Routine vision screening is a necessary part of that detection and has traditionally involved acuity charts. However, photoscreening in which "red eye" is elicited to show whether each eye is focusing may outperform routine acuity…

Effects of Contextual Predictability and Transitional Probability on Eye Movements During Reading

ERIC Educational Resources Information Center

Frisson, Steven; Rayner, Keith; Pickering, Martin J.

2005-01-01

In 2 eye-movement experiments, the authors tested whether transitional probability (the statistical likelihood that a word precedes or follows another word) affects reading times and whether this occurs independently from contextual predictability effects. Experiment 1 showed early effects of predictability, replicating S. A. McDonald and R. C.…

Semantic Preview Benefit in Eye Movements during Reading: A Parafoveal Fast-Priming Study

ERIC Educational Resources Information Center

Hohenstein, Sven; Laubrock, Jochen; Kliegl, Reinhold

2010-01-01

Eye movements in reading are sensitive to foveal and parafoveal word features. Whereas the influence of orthographic or phonological parafoveal information on gaze control is undisputed, there has been no reliable evidence for early parafoveal extraction of semantic information in alphabetic script. Using a novel combination of the gaze-contingent…

Sufism in the Novel: "Cat's Eyes"

ERIC Educational Resources Information Center

Miniawi, Nayera

2013-01-01

"Cat's Eyes" is a novel about suffering and endurance, early marriage, spirituality and the sanctuary it provides, and Sufism in particular. It uses certain motifs to depict the psychological suffering of a young girl, caused by her conservative father and unsatisfactory marriage, which persists until she finally reaches a moment of…

Performing pediatric eye exams in primary care.

PubMed

Martin, Elaine F

2017-08-17

Early vision care is critical for all children. If undetected, eye disorders such as amblyopia and strabismus may result in permanent vision loss. Vision exams should include a careful history and physical including fix and follow, red reflex, and cover/uncover testing. Photo screening and visual acuity exams should be administered whenever possible.

The relationship of major American dietary patterns to age-related macular degeneration

USDA-ARS?s Scientific Manuscript database

We hypothesized that major American dietary patterns are associated with age-related macular degeneration (AMD) risk. This was a cross-sectional study with 8,103 eyes from 4,088 eligible participants in the baseline Age-Related Eye Disease Study (AREDS) were classified into control (n=2,739), early ...

Visualization of dietary patterns and their associations with age-related macular degeneration

USDA-ARS?s Scientific Manuscript database

PURPOSE: We aimed to visualize the relationship of predominant dietary patterns and their associations with AMD. METHODS: A total of 8103 eyes from 4088 participants in the baseline Age-Related Eye Disease Study (AREDS) were classified into three groups: control (n=2739), early AMD (n=4599), and adv...

Binocular eye movement control and motion perception: what is being tracked?

PubMed

van der Steen, Johannes; Dits, Joyce

2012-10-19

We investigated under what conditions humans can make independent slow phase eye movements. The ability to make independent movements of the two eyes generally is attributed to few specialized lateral eyed animal species, for example chameleons. In our study, we showed that humans also can move the eyes in different directions. To maintain binocular retinal correspondence independent slow phase movements of each eye are produced. We used the scleral search coil method to measure binocular eye movements in response to dichoptically viewed visual stimuli oscillating in orthogonal direction. Correlated stimuli led to orthogonal slow eye movements, while the binocularly perceived motion was the vector sum of the motion presented to each eye. The importance of binocular fusion on independency of the movements of the two eyes was investigated with anti-correlated stimuli. The perceived global motion pattern of anti-correlated dichoptic stimuli was perceived as an oblique oscillatory motion, as well as resulted in a conjugate oblique motion of the eyes. We propose that the ability to make independent slow phase eye movements in humans is used to maintain binocular retinal correspondence. Eye-of-origin and binocular information are used during the processing of binocular visual information, and it is decided at an early stage whether binocular or monocular motion information and independent slow phase eye movements of each eye are produced during binocular tracking.

Binocular Eye Movement Control and Motion Perception: What Is Being Tracked?

PubMed Central

van der Steen, Johannes; Dits, Joyce

2012-01-01

Purpose. We investigated under what conditions humans can make independent slow phase eye movements. The ability to make independent movements of the two eyes generally is attributed to few specialized lateral eyed animal species, for example chameleons. In our study, we showed that humans also can move the eyes in different directions. To maintain binocular retinal correspondence independent slow phase movements of each eye are produced. Methods. We used the scleral search coil method to measure binocular eye movements in response to dichoptically viewed visual stimuli oscillating in orthogonal direction. Results. Correlated stimuli led to orthogonal slow eye movements, while the binocularly perceived motion was the vector sum of the motion presented to each eye. The importance of binocular fusion on independency of the movements of the two eyes was investigated with anti-correlated stimuli. The perceived global motion pattern of anti-correlated dichoptic stimuli was perceived as an oblique oscillatory motion, as well as resulted in a conjugate oblique motion of the eyes. Conclusions. We propose that the ability to make independent slow phase eye movements in humans is used to maintain binocular retinal correspondence. Eye-of-origin and binocular information are used during the processing of binocular visual information, and it is decided at an early stage whether binocular or monocular motion information and independent slow phase eye movements of each eye are produced during binocular tracking. PMID:22997286

Hyperosmolarity response of ocular standing potential as a clinical test for retinal pigment epithelium activity. Chorioretinal dystrophies.

PubMed

Yonemura, D; Kawasaki, K; Madachi-Yamamoto, S

1984-05-30

The hyperosmolarity response of the standing potential was recorded in retinitis pigmentosa (20 eyes), central (pericentral) retinitis pigmentosa (4 eyes), pigmented paravenous retinochoroidal atrophy (2 eyes), fundus albipunctatus (8 eyes), and Stargardt's disease (or fundus flavimaculatus) (14 eyes). The light peak/dark trough ratio (the L/D ratio) and the Diamox response were also determined. The hyperosmolarity response was greatly suppressed (less than M-4SD; M and SD indicate respectively the mean and the standard deviation in normal control subjects) in all examined eyes with retinitis pigmentosa (20 eyes) including retinitis pigmentosa sine pigmento (8 eyes), central (pericentral) retinitis pigmentosa (4 eyes), and pigmented paravenous retinochoroidal atrophy (2 eyes). The L/D ratio was larger than 1.26 (M-2.5 SD) in the half of the eyes with the above-described diseases. The hyperosmolarity response was abnormal (less than M-2 SD) in 4 of 8 eyes with fundus albipunctatus. The L/D ratio was normal in all 8 eyes. The hyperosmolarity response was abnormal (less than M-2 SD) in all 14 eyes with Stargardt's disease or fundus flavimaculatus. The L/D ratio was abnormal in 5 of these 14 eyes. The hyperosmolarity response was more frequently abnormal than the L/D ratio in the chorioretinal dystrophies mentioned above, and hence is useful particularly for early diagnosis of these disorders.

Hyperosmolarity response of ocular standing potential as a clinical test for retinal pigment epithelium activity chorioretinal dystrophies.

PubMed

Yonemura, D; Kawasaki, K; Madachi-Yamamoto, S

1984-05-01

The hyperosmolarity response of the standing potential was recorded in retinitis pigmentosa (20 eyes), central (pericentral) retinitis pigmentosa (4 eyes), pigmented paravenous retinochoroidal atrophy (2 eyes), fundus albipunctatus (8 eyes), and Stargardt's disease (or fundus flavimaculatus) (14 eyes). The light peak/dark trough ratio (the L/D ratio) and the Diamox response were also determined.The hyperosmolarity response was greatly suppressed (less than M-4SD; M and SD indicate respectively the mean and the standard deviation in normal control subjects) in all examined eyes with retinitis pigmentosa (20 eyes) including retinitis pigmentosa sine pigmento (8 eyes), central (pericentral) retinitis pigmentosa (4 eyes), and pigmented paravenous retinochoroidal atrophy (2 eyes). The L/D ratio was larger than 1.26 (M-2.5 SD) in the half of the eyes with the above-described diseases.The hyperosmolarity response was abnormal (less than M-2 SD) in 4 of 8 eyes with fundus albipunctatus. The L/D ratio was normal in all 8 eyes.The hyperosmolarity response was abnormal (less than M-2 SD) in all 14 eyes with Stargardt's disease or fundus flavimaculatus. The L/D ratio was abnormal in 5 of these 14 eyes.The hyperosmolarity response was more frequently abnormal than the L/D ratio in the chorioretinal dystrophies mentioned above, and hence is useful particularly for early diagnosis of these disorders.

Attention training for infants at familial risk of ADHD (INTERSTAARS): study protocol for a randomised controlled trial.

PubMed

Goodwin, Amy; Salomone, Simona; Bolton, Patrick; Charman, Tony; Jones, Emily J H; Pickles, Andrew; Robinson, Emily; Smith, Tim; Sonuga-Barke, Edmund J S; Wass, Sam; Johnson, Mark H

2016-12-28

Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder that can negatively impact on an individual's quality of life. It is pathophysiologically complex and heterogeneous with different neuropsychological processes being impaired in different individuals. Executive function deficits, including those affecting attention, working memory and inhibitory control, are common. Cognitive training has been promoted as a treatment option, based on the notion that by strengthening the neurocognitive networks underlying these executive processes, ADHD symptoms will also be reduced. However, if implemented in childhood or later, when the full disorder has become well-established, cognitive training has only limited value. INTERSTAARS is a trial designed to test a novel approach to intervention, in which cognitive training is implemented early in development, before the emergence of the disorder. The aim of INTERSTAARS is to train early executive skills, thereby increasing resilience and reducing later ADHD symptoms and associated impairment. Fifty 10-14-month-old infants at familial risk of ADHD will participate in INTERSTAARS. Infants will be randomised to an intervention or a control group. The intervention aims to train early attention skills by using novel eye-tracking technology and gaze-contingent training paradigms. Infants view animated games on a screen and different events take place contingent on where on the screen the infant is looking. Infants allocated to the intervention will receive nine weekly home-based attention training sessions. Control group infants will also receive nine weekly home visits, but instead of viewing the training games during these visits they will view non-gaze-contingent age-appropriate videos. At baseline and post treatment, infant attention control will be assessed using a range of eye-tracking, observational, parent-report and neurophysiological measures. The primary outcome will be a composite of eye-tracking tasks used to assess infant attention skills. Follow-up data will be collected on emerging ADHD symptoms when the infants are 2 and 3 years old. This is the first randomised controlled trial to assess the potential efficacy of cognitive training as a prevention measure for infants at familial risk of ADHD. If successful, INTERSTAARS could offer a promising new approach for developing early interventions for ADHD. International Standard Randomised Controlled Trial registry: ISRCTN37683928 . Registered on 22 June 2015.

The Role of Predictability in Saccadic Eye Responses in the Suppression Head Impulse Test of Horizontal Semicircular Canal Function.

PubMed

Rey-Martinez, Jorge; Yanes, Joaquin; Esteban, Jonathan; Sanz, Ricardo; Martin-Sanz, Eduardo

2017-01-01

In the suppression head impulse paradigm (SHIMP) vHIT protocol, the participant is instructed to follow with his gaze a mobile target generated by a laser placed on the participant's head. Recent studies have reported that the refixation saccade latencies are in relation with the time evolution of the vestibular dysfunction in both (standard and SHIMP) procedures. We hypothesized that some central mechanisms like head impulse prediction could be one of the causes for the differences in the saccadic eye responses. A prospective cohort non-randomized study was designed. For the SHIMP protocol, recorded with the ICS Impulse ver. 4.0 ® (Otometrics A/S, Taastrup, Denmark) vHIT device, three different algorithms were performed: "predictable," "less predictable," and "unpredictable" depending on the target's predictability. A mathematical method was developed to analyze the SHIMP responses. The method was implemented as an additional tool to the MATLAB open source script for the extended analysis of the vHIT responses named HITCal. In cohort 1, 52 participants were included in "predictable" SHIMP protocol. In cohort 2, 60 patients were included for the "less predictable" and 35 patients for the "unpredictable" SHIMP protocol. The participants made more early saccades when instructed to perform the "predictable" paradigm compared with the "less predictable" paradigm ( p  < 0.001). The less predictable protocol did not reveal any significant difference when compared with the unpredictable protocol ( p  = 0.189). For the latency of the first saccade, there was statistical difference between the "unpredictable" and "predictable" protocols ( p  < 0.001) and between the "less predictable" and "predictable" protocols ( p  < 0.001). Finally, we did not find any relationship between the horizontal vestibulo-ocular reflex (hVOR) gain and the latency of the saccades. We developed a specific method to analyze and detect early SHIMP saccades. Our findings offer evidence regarding the influence of predictability on the latency of the SHIMP saccadic responses, suggesting that early saccades are probably caused by a conditioned response of the participant. The lack of relationship between the hVOR gain and the latency of the saccades suggests that the predictive behavior that caused the early eye saccades are independent of the vestibular function.

Influence of visual experience on developmental shift from long-term depression to long-term potentiation in the rat medial vestibular nuclei

PubMed Central

Grassi, Silvarosa; Dieni, Cristina; Frondaroli, Adele; Pettorossi, Vito Enrico

2004-01-01

The influence of visual experience deprivation on changes in synaptic plasticity during postnatal development was studied in the ventral part of the rat medial vestibular nuclei (vMVN). We analysed the differences in the occurrence, expressed as a percentage, of long-term depression (LTD) and long-term potentiation (LTP) induced by high frequency stimulation (HFS) of the primary vestibular afferents in rats reared in the light (LR) and those in the dark (DR). In LR rats, HFS only induced LTD in the early stages of development, but the occurrence of LTD progressively decreased to zero before their eyes opened, while that of LTP enhanced from zero to about 50%. Once the rats' eyes had opened, LTD was no longer inducible while LTP occurrence gradually reached the normal adult value (70%). In DR rats, a similar shift from LTD to LTP was observed before their eyes opened, showing only a slightly slower LTD decay and LTP growth, and the LTD annulment was delayed by 1 day. By contrast, the time courses of LTD and LTP development in DR and LR rats showed remarkable differences following eye opening. In fact, LTD occurrence increased to about 50% in a short period of time and remained high until the adult stage. In addition, the occurrence of LTP slowly decreased to less than 20%. The effect of light-deprivation was reversible, since the exposure of DR rats to light, 5 days after eye opening, caused a sudden disappearance of LTD and a partial recover of LTP occurrence. In addition, we observed that a week of light deprivation in LR adult rats did not affect the normal adult LTP occurrence. These results provide evidence that in a critical period of development visual input plays a crucial role in shaping synaptic plasticity of the vMVN, and suggest that the visual guided shift from LTD to LTP during development may be necessary to refine and consolidate vestibular circuitry. PMID:15331680

Modified incision for maxillectomy: our experience.

PubMed

Bhavana, Kranti; Tyagi, Isha; Ramani, Mukesh Kumar

2012-06-01

Radical maxillectomy has usually been done by the classical Weber Ferguson incision since age old times and still is being used widely due to its advantage of excellent exposure and minimal scarring as the incision follows the natural skin crease. In our modification of radical maxillectomy incision we avoid a scar on the midface by performing a midface degloving and combining it with a subconjunctival eye incision thus avoiding any cosmetic deformity and associated eye complication. It also avoids the late complication of cutaneous fistula following radiotherapy to these areas and due to early healing of the wound, early radiotherapy can be started.

Wide Eyes and Drooping Arms: Adult-Like Congruency Effects Emerge Early in the Development of Sensitivity to Emotional Faces and Body Postures

ERIC Educational Resources Information Center

Mondloch, Catherine J.; Horner, Matthew; Mian, Jasmine

2013-01-01

Adults' and 8-year-old children's perception of emotional faces is disrupted when faces are presented in the context of incongruent body postures (e.g., when a sad face is displayed on a fearful body) if the two emotions are highly similar (e.g., sad/fear) but not if they are highly dissimilar (e.g., sad/happy). The current research investigated…

Development of a risk score for geographic atrophy in complications of the age-related macular degeneration prevention trial.

PubMed

Ying, Gui-Shuang; Maguire, Maureen G

2011-02-01

To develop a risk score for developing geographic atrophy (GA) involving easily obtainable information among patients with bilateral large drusen. Cohort study within a multicenter randomized clinical trial. We included 1052 participants with ≥ 10 large (>125 μm) drusen and visual acuity ≥ 20/40 in each eye. In the Complications of Age-related Macular Degeneration (AMD) Prevention Trial (CAPT), 1 eye of each participant was randomly assigned to laser treatment and the contralateral eye was assigned to observation to evaluate whether laser treatment of drusen could prevent vision loss. Gradings by a reading center were used to identify: CAPT end point GA (total area of GA [>250 μm] > 1 disc area), GA (>175 μm) involving the foveal center (CGA), and GA of any size and location (any GA). Established risk factors (age, smoking status, hypertension, Age-related Eye Disease Study simple severity scale score), both with and without a novel risk factor (night vision score), were used in assigning risk points. The risk scores were evaluated for the ability to discriminate and calibrate GA risk. Development of end point GA, CGA, and any GA. Among 942 CAPT participants who completed 5 years of follow-up and did not have any GA at baseline, 6.8% participants developed CAPT end point GA, 9.6% developed CGA, and 34.4% developed any GA. The 5-year incidence of end point GA in 1 or both eyes of a participant increased with the 15-point GA risk score, from 0.6% for <7 points to 15% for ≥ 12 points. The 5-factor risk score predicted development of GA moderately well with the area under the receiver operating characteristic curve (AUC) 0.76 (95% confidence interval [CI], 0.71-0.81) for end point GA; 0.76 (95% CI, 0.71-0.80) for CGA, and 0.68 (95% CI, 0.65-0.72) for any GA. Prediction from the risk score without the night vision score had lower AUCs (range, 0.67-0.72). If validated in other patients, the GA risk score will be useful for identifying high-risk patients for clinical trials of prevention of GA and for clinical assessment of GA risk in early AMD patients. Copyright © 2011 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

Eye contact modulates facial mimicry in 4-month-old infants: An EMG and fNIRS study.

PubMed

de Klerk, Carina C J M; Hamilton, Antonia F de C; Southgate, Victoria

2018-05-16

Mimicry, the tendency to spontaneously and unconsciously copy others' behaviour, plays an important role in social interactions. It facilitates rapport between strangers, and is flexibly modulated by social signals, such as eye contact. However, little is known about the development of this phenomenon in infancy, and it is unknown whether mimicry is modulated by social signals from early in life. Here we addressed this question by presenting 4-month-old infants with videos of models performing facial actions (e.g., mouth opening, eyebrow raising) and hand actions (e.g., hand opening and closing, finger actions) accompanied by direct or averted gaze, while we measured their facial and hand muscle responses using electromyography to obtain an index of mimicry (Experiment 1). In Experiment 2 the infants observed the same stimuli while we used functional near-infrared spectroscopy to investigate the brain regions involved in modulating mimicry by eye contact. We found that 4-month-olds only showed evidence of mimicry when they observed facial actions accompanied by direct gaze. Experiment 2 suggests that this selective facial mimicry may have been associated with activation over posterior superior temporal sulcus. These findings provide the first demonstration of modulation of mimicry by social signals in young human infants, and suggest that mimicry plays an important role in social interactions from early in life. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

Histologic development of the human fovea from midgestation to maturity.

PubMed

Hendrickson, Anita; Possin, Daniel; Vajzovic, Lejla; Toth, Cynthia A

2012-11-01

To describe the histologic development of the human central retina from fetal week (Fwk) 22 to 13 years. Retrospective observational case series. Retinal layers and neuronal substructures were delineated on foveal sections of fixed tissue stained in azure II-methylene blue and on frozen sections immunolabeled for cone, rod, or glial proteins. Postmortem tissue was from 11 eyes at Fwk 20-27; 8 eyes at Fwk 28-37; 6 eyes at postnatal 1 day to 6 weeks; 3 eyes at 9 to 15 months; and 5 eyes at 28 months to 13 years. At Fwk 20-22 the fovea could be identified by the presence of a single layer of cones in the outer nuclear layer. Immunolabeling detected synaptic proteins, cone and rod opsins, and Müller glial processes separating the photoreceptors. The foveal pit appeared at Fwk 25, involving progressive peripheral displacement of ganglion cell, inner plexiform, and inner nuclear layers. The pit became wider and shallower after birth, and appeared mature by 15 months. Between Fwk 25 and Fwk 38, all photoreceptors developed more distinct inner and outer segments, but these were longer on peripheral than foveal cones. After birth the foveal outer nuclear layer became much thicker as cone packing occurred. Cone packing and neuronal migration during pit formation combined to form long central photoreceptor axons, which changed the outer plexiform layer from a thin sheet of synaptic pedicles into the thickest layer in the central retina by 15 months. Foveal inner and outer segment length matched peripheral cones by 15 months and was 4 times longer by 13 years. These data are necessary to understand the marked changes in human retina from late gestation to early adulthood. They provide qualitative and quantitative morphologic information required to interpret the changes in hyper- and hyporeflexive bands in pediatric spectral-domain optical coherence tomography images at the same ages. Copyright © 2012 Elsevier Inc. All rights reserved.

The Auckland keratoconus study: identifying predictors of acute corneal hydrops in keratoconus.

PubMed

Fan Gaskin, Jennifer C; Good, William R; Jordan, Charlotte A; Patel, Dipika V; McGhee, Charles Nj

2013-03-01

The aim was to identify potential factors associated with acute corneal hydrops in a New Zealand population with keratoconus referred to a hospital eye service. In a single hospital centre, in a retrospective review, demographic and clinical features of subjects with keratoconus and corneal hydrops over a 17-year period were compared with an age- and gender-matched control group of subjects with keratoconus but no history of corneal hydrops. One hundred and one eyes of 101 subjects (mean age 24.6 ± 8.4 years) were identified with keratoconus-related corneal hydrops. Subjects were more likely to be of Pacific but less likely to be of New Zealand European ethnicity than control subjects (n = 101). In comparison, Maori ethnicity was not found to have a significantly positive or negative association with hydrops. The pre-hydrops visual acuity (VA) of affected eyes was poorer than that of controls (p < 0.001) at first presentation to our tertiary referral corneal and contact lens service. Hydrops typically developed approximately four years after diagnosis of keratoconus. Subjects with hydrops were more likely to have a history of eye-rubbing (p = 0.011) but less likely to have a family history of keratoconus (p = 0.05). In 31 cases, the acute hydrops event was their first optometric/ophthalmologic contact. There were no statistically significant differences in the prevalence of atopic disease, contact lens wear or overall corneal transplantation rate between the two groups. Pacific ethnicity, history of eye-rubbing, poor VA at first hospital presentation and lack of family history were statistically associated with developing acute corneal hydrops in keratoconus in a New Zealand population. Greater understanding of such predisposing risk factors may help develop early management strategies to delay or prevent progression of this disease. © 2013 The Authors. Clinical and Experimental Optometry © 2013 Optometrists Association Australia.

Allocation of distinct organ fates from a precursor field requires a shift in expression and function of gene regulatory networks

PubMed Central

Zhu, Jinjin; Baker, Luke R.; Bashirullah, Arash

2018-01-01

A common occurrence in metazoan development is the rise of multiple tissues/organs from a single uniform precursor field. One example is the anterior forebrain of vertebrates, which produces the eyes, hypothalamus, diencephalon, and telencephalon. Another instance is the Drosophila wing disc, which generates the adult wing blade, the hinge, and the thorax. Gene regulatory networks (GRNs) that are comprised of signaling pathways and batteries of transcription factors parcel the undifferentiated field into discrete territories. This simple model is challenged by two observations. First, many GRN members that are thought to control the fate of one organ are actually expressed throughout the entire precursor field at earlier points in development. Second, each GRN can simultaneously promote one of the possible fates choices while repressing the other alternatives. It is therefore unclear how GRNs function to allocate tissue fates if their members are uniformly expressed and competing with each other within the same populations of cells. We address this paradigm by studying fate specification in the Drosophila eye-antennal disc. The disc, which begins its development as a homogeneous precursor field, produces a number of adult structures including the compound eyes, the ocelli, the antennae, the maxillary palps, and the surrounding head epidermis. Several selector genes that control the fates of the eye and antenna, respectively, are first expressed throughout the entire eye-antennal disc. We show that during early stages, these genes are tasked with promoting the growth of the entire field. Upon segregation to distinct territories within the disc, each GRN continues to promote growth while taking on the additional roles of promoting distinct primary fates and repressing alternate fates. The timing of both expression pattern restriction and expansion of functional duties is an elemental requirement for allocating fates within a single field. PMID:29351292

Mouse Models as Tools to Identify Genetic Pathways for Retinal Degeneration, as Exemplified by Leber's Congenital Amaurosis.

PubMed

Chang, Bo

2016-01-01

Leber's congenital amaurosis (LCA) is an inherited retinal degenerative disease characterized by severe loss of vision in the first year of life. In addition to early vision loss, a variety of other eye-related abnormalities including roving eye movements, deep-set eyes, and sensitivity to bright light also occur with this disease. Many animal models of LCA are available and the study them has led to a better understanding of the pathology of the disease, and has led to the development of therapeutic strategies aimed at curing or slowing down LCA. Mouse models, with their well-developed genetics and similarity to human physiology and anatomy, serve as powerful tools with which to investigate the etiology of human LCA. Such mice provide reproducible, experimental systems for elucidating pathways of normal development, function, designing strategies and testing compounds for translational research and gene-based therapies aimed at delaying the diseases progression. In this chapter, I describe tools used in the discovery and evaluation of mouse models of LCA including a Phoenix Image-Guided Optical Coherence Tomography (OCT) and a Diagnosys Espion Visual Electrophysiology System. Three mouse models are described, the rd3 mouse model for LCA12 and LCA1, the rd12 mouse model for LCA2, and the rd16 mouse model for LCA10.

The feasibility of automated eye tracking with the Early Childhood Vigilance Test of attention in younger HIV-exposed Ugandan children.

PubMed

Boivin, Michael J; Weiss, Jonathan; Chhaya, Ronak; Seffren, Victoria; Awadu, Jorem; Sikorskii, Alla; Giordani, Bruno

2017-07-01

Tobii eye tracking was compared with webcam-based observer scoring on an animation viewing measure of attention (Early Childhood Vigilance Test; ECVT) to evaluate the feasibility of automating measurement and scoring. Outcomes from both scoring approaches were compared with the Mullen Scales of Early Learning (MSEL), Color-Object Association Test (COAT), and Behavior Rating Inventory of Executive Function for preschool children (BRIEF-P). A total of 44 children 44 to 65 months of age were evaluated with the ECVT, COAT, MSEL, and BRIEF-P. Tobii ×2-30 portable infrared cameras were programmed to monitor pupil direction during the ECVT 6-min animation and compared with observer-based PROCODER webcam scoring. Children watched 78% of the cartoon (Tobii) compared with 67% (webcam scoring), although the 2 measures were highly correlated (r = .90, p = .001). It is possible for 2 such measures to be highly correlated even if one is consistently higher than the other (Bergemann et al., 2012). Both ECVT Tobii and webcam ECVT measures significantly correlated with COAT immediate recall (r = .37, p = .02 vs. r = .38, p = .01, respectively) and total recall (r = .33, p = .06 vs. r = .42, p = .005) measures. However, neither the Tobii eye tracking nor PROCODER webcam ECVT measures of attention correlated with MSEL composite cognitive performance or BRIEF-P global executive composite. ECVT scoring using Tobii eye tracking is feasible with at-risk very young African children and consistent with webcam-based scoring approaches in their correspondence to one another and other neurocognitive performance-based measures. By automating measurement and scoring, eye tracking technologies can improve the efficiency and help better standardize ECVT testing of attention in younger children. This holds promise for other neurodevelopmental tests where eye movements, tracking, and gaze length can provide important behavioral markers of neuropsychological and neurodevelopmental processes associated with such tests. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Lamina Cribrosa Microarchitecture in Monkey Early Experimental Glaucoma: Global Change

PubMed Central

Reynaud, Juan; Lockwood, Howard; Gardiner, Stuart K.; Williams, Galen; Yang, Hongli; Burgoyne, Claude F.

2016-01-01

Purpose The purpose of this study was to characterize experimental glaucoma (EG) versus control eye differences in lamina cribrosa (LC), beam diameter (BD), pore diameter (PD), connective tissue volume fraction (CTVF), connective tissue volume (CTV), and LC volume (LV) in monkey early EG. Methods Optic nerve heads (ONHs) of 14 unilateral EG and 6 bilateral normal (BN) monkeys underwent three-dimensional reconstruction and LC beam segmentation. Each beam and pore voxel was assigned a diameter based on the largest sphere that contained it before transformation to a common cylinder with inner, middle, and outer layers. Full-thickness and layer averages for BD, PD, CTVF, CTV, and LV were calculated for each ONH. Beam diameter and PD distributions for each ONH were fit to a gamma distribution and summarized by scale and shape parameters. Experimental glaucoma and depth effects were assessed for each parameter by linear mixed-effects (LME) modeling. Animal-specific EG versus control eye differences that exceeded the maximum intereye difference among the six BN animals were considered significant. Results Overall EG eye mean PD was 12.8% larger (28.2 ± 5.6 vs. 25.0 ± 3.3 μm), CTV was 26.5% larger (100.06 ± 47.98 vs. 79.12 ± 28.35 × 106 μm3), and LV was 40% larger (229.29 ± 98.19 vs. 163.63 ± 39.87 × 106 μm3) than control eyes (P ≤ 0.05, LME). Experimental glaucoma effects were significantly different by layer for PD (P = 0.0097) and CTVF (P < 0.0001). Pore diameter expanded consistently across all PDs. Experimental glaucoma eye-specific parameter change was variable in magnitude and direction. Conclusions Pore diameter, CTV, and LV increase in monkey early EG; however, EG eye-specific change is variable and includes both increases and decreases in BD and CTVF. PMID:27362781

Ophthalmology in North America: Early Stories (1491-1801)

PubMed Central

Leffler, Christopher T; Schwartz, Stephen G; Wainsztein, Ricardo D; Pflugrath, Adam; Peterson, Eric

2017-01-01

New World plants, such as tobacco, tomato, and chili, were held to have beneficial effects on the eyes. Indigenous healers rubbed or scraped the eyes or eyelids to treat inflammation, corneal opacities, and even eye irritation from smoke. European settlers used harsh treatments, such as bleeding and blistering, when the eyes were inflamed or had loss of vision with a normal appearance (gutta serena). In New Spain, surgery for corneal opacity was performed in 1601 and cataract couching in 1611. North American physicians knew of contralateral loss of vision after trauma or surgery (sympathetic ophthalmia), which they called “sympathy.” To date, the earliest identified cataract couching by a surgeon trained in the New World was performed in 1769 by John Bartlett of Rhode Island. The American Revolution negatively affected ophthalmology, as loyalist surgeons were expelled and others were consumed with wartime activities. After the war, cataract extraction was imported to America in earnest and academic development resumed. Charles F Bartlett, the son of John, performed cataract extraction but was also a “rapacious privateer.” In 1801, a doctor in the frontier territory of Kentucky observed anticholinergic poisoning by Datura stramonium (Jimsonweed) and suggested that this agent be applied topically to dilate the pupil before cataract extraction. John Warren at Harvard preferred couching in the 1790s, but, after his son returned from European training, recommended treating angle closure glaucoma by lens extraction. Other eye procedures described or advertised in America before the 19th century included enucleation, resection of conjunctival lesions or periocular tumors, treatment of lacrimal fistula, and fitting of prosthetic eyes. PMID:28804247

Gaze holding deficits discriminate early from late onset cerebellar degeneration.

PubMed

Tarnutzer, Alexander A; Weber, K P; Schuknecht, B; Straumann, D; Marti, S; Bertolini, G

2015-08-01

The vestibulo-cerebellum calibrates the output of the inherently leaky brainstem neural velocity-to-position integrator to provide stable gaze holding. In healthy humans small-amplitude centrifugal nystagmus is present at extreme gaze-angles, with a non-linear relationship between eye-drift velocity and eye eccentricity. In cerebellar degeneration this calibration is impaired, resulting in pathological gaze-evoked nystagmus (GEN). For cerebellar dysfunction, increased eye drift may be present at any gaze angle (reflecting pure scaling of eye drift found in controls) or restricted to far-lateral gaze (reflecting changes in shape of the non-linear relationship) and resulting eyed-drift patterns could be related to specific disorders. We recorded horizontal eye positions in 21 patients with cerebellar neurodegeneration (gaze-angle = ±40°) and clinically confirmed GEN. Eye-drift velocity, linearity and symmetry of drift were determined. MR-images were assessed for cerebellar atrophy. In our patients, the relation between eye-drift velocity and gaze eccentricity was non-linear, yielding (compared to controls) significant GEN at gaze-eccentricities ≥20°. Pure scaling was most frequently observed (n = 10/18), followed by pure shape-changing (n = 4/18) and a mixed pattern (n = 4/18). Pure shape-changing patients were significantly (p = 0.001) younger at disease-onset compared to pure scaling patients. Atrophy centered around the superior/dorsal vermis, flocculus/paraflocculus and dentate nucleus and did not correlate with the specific drift behaviors observed. Eye drift in cerebellar degeneration varies in magnitude; however, it retains its non-linear properties. With different drift patterns being linked to age at disease-onset, we propose that the gaze-holding pattern (scaling vs. shape-changing) may discriminate early- from late-onset cerebellar degeneration. Whether this allows a distinction among specific cerebellar disorders remains to be determined.

Effects of spray-dried Pseudomonas fluorescens, strain CL145A (Zequanox®) on reproduction and early development of the fathead minnow (Pimephales promelas).

USGS Publications Warehouse

Waller, Diane L.; Luoma, James A.

2016-01-01

The biopesticide, Zequanox®, is registered for dreissenid mussel control in open water systems. Previous toxicity trials with nontarget organisms, including young-of-the year of several fish species and invertebrates, demonstrated selectivity of Zequanox for dreissenids. However, data are lacking on its safety to reproductive and early life stages of fish. The present study evaluated the effects of Zequanox on spawning and early life stages of the fathead minnow, Pimephales promelas, at the maximum approved concentration (100 mg Zequanox active ingredient /L) and exposure duration (8 h) for open water application. The results showed no significant effect of Zequanox on survival, condition, or cumulative egg deposition (21 d) in adult fathead minnow. Eggs (<24-h old) exposed to Zequanox developed to the eyed-stage at a similar rate to that of unexposed eggs. Additionally, Zequanox did not have a significant effect on survival and growth (90 d) of newly hatched fry (<24-h old). The results indicate that Zequanox treatment will not affect survival, spawning, and early life development of fathead minnows when applied at the recommended treatment regime.

Routine Eye Examinations for Persons 20-64 Years of Age

PubMed Central

2006-01-01

Executive Summary Objective The objective of this analysis was to determine the strength of association between age, gender, ethnicity, family history of disease and refractive error and the risk of developing glaucoma or ARM? Clinical Need A routine eye exam serves a primary, secondary, and tertiary care role. In a primary care role, it allows contact with a doctor who can provide advice about eye care, which may reduce the incidence of eye disease and injury. In a secondary care role, it can via a case finding approach, diagnose persons with degenerative eye diseases such as glaucoma and or AMD, and lead to earlier treatment to slow the progression of the disease. Finally in a tertiary care role, it provides ongoing monitoring and treatment to those with diseases associated with vision loss. Glaucoma is a progressive degenerative disease of the optic nerve, which causes gradual loss of peripheral (side) vision, and in advanced disease states loss of central vision. Blindness may results if glaucoma is not diagnosed and managed. The prevalence of primary open angle glaucoma (POAG) ranges from 1.1% to 3.0% in Western populations, and from 4.2% to 8.8% in populations of African descent. It is estimated up to 50% of people with glaucoma are aware that they have the disease. In Canada, glaucoma disease is the second leading cause of blindness in people aged 50 years and older. Tonometry, inspection of the optic disc and perimetry are used concurrently by physicians and optometrists to make the diagnosis of glaucoma. In general, the evidence shows that treating people with increased IOP only, increased IOP and clinical signs of early glaucoma or with normal-tension glaucoma can reduce the progression of disease. Age-related maculopathy (ARM) is a degenerative disease of the macula, which is a part of the retina. Damage to the macula causes loss of central vision affecting the ability to read, recognize faces and to move about freely. ARM can be divided into an early- stage (early ARM) and a late-stage (AMD). AMD is the leading cause of blindness in developed countries. The prevalence of AMD increases with increasing age. It is estimated that 1% of people 55 years of age, 5% aged 75 to 84 years and 15% 80 years of age and older have AMD. ARM can be diagnosed during fundoscopy (ophthalmoscopy) which is a visual inspection of the retina by a physician or optometrist, or from a photograph of the retina. There is no cure or prevention for ARM. Likewise, there is currently no treatment to restore vision lost due to AMD. However, there are treatments to delay the progression of the disease and further loss of vision. The Technology A periodic oculo-visual assessment is defined “as an examination of the eye and vision system rendered primarily to determine if a patient has a simple refractive error (visual acuity assessment) including myopia, hypermetropia, presbyopia, anisometropia or astigmatism.” This service includes a history of the presenting complaint, past medical history, visual acuity examination, ocular mobility examination, slit lamp examination of the anterior segment, ophthalmoscopy, and tonometry (measurement of IOP) and is completed by either a physician or an optometrist. Review Strategy The Medical Advisory Secretariat conducted a computerized search of the literature in the following databases: OVID MEDLINE, MEDLINE, In-Process & Other Non-Indexed Citations, EMBASE, INAHTA and the Cochrane Library. The search was limited to English-language articles with human subjects, published from January 2000 to March 2006. In addition, a search was conducted for published guidelines, health technology assessments, and policy decisions. Bibliographies of references of relevant papers were searched for additional references that may have been missed in the computerized database search. Studies including participants 20 years and older, population-based prospective cohort studies, population-based cross-sectional studies when prospective cohort studies were unavailable or insufficient and studies determining and reporting the strength of association or risk- specific prevalence or incidence rates of either age, gender, ethnicity, refractive error or family history of disease and the risk of developing glaucoma or AMD were included in the review. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) system was used to summarize the overall quality of the body of evidence. Summary of Findings A total of 498 citations for the period January 2000 through February 2006 were retrieved and an additional 313 were identified when the search was expanded to include articles published between 1990 and 1999. An additional 6 articles were obtained from bibliographies of relevant articles. Of these, 36 articles were retrieved for further evaluation. Upon review, 1 meta-analysis and 15 population-based epidemiological studies were accepted for this review Primary Open Angle Glaucoma Age Six cross-sectional studies and 1 prospective cohort study contributed data on the association between age and PAOG. From the data it can be concluded that the prevalence and 4-year incidence of POAG increases with increasing age. The odds of having POAG are statistically significantly greater for people 50 years of age and older relative to those 40 to 49 years of age. There is an estimated 7% per year incremental odds of having POAG in persons 40 years of age and older, and 10% per year in persons 49 years of age and older. POAG is undiagnosed in up to 50% of the population. The quality of the evidence is moderate. Gender Five cross-sectional studies evaluated the association between gender and POAG. Consistency in estimates is lacking among studies and because of this the association between gender and prevalent POAG is inconclusive. The quality of the evidence is very low. Ethnicity Only 1 cross-sectional study compared the prevalence rates of POAG between black and white participants. These data suggest that prevalent glaucoma is statistically significantly greater in a black population 50 years of age and older compared with a white population of similar age. There is an overall 4-fold increase in prevalent POAG in a black population compared with a white population. This increase may be due to a confounding variable not accounted for in the analysis. The quality of the evidence is low. Refractive Error Four cross-sectional studies assessed the association of myopia and POAG. These data suggest an association between myopia defined as a spherical equivalent of -1.00D or worse and prevalent POAG. However, there is inconsistency in results regarding the statistical significance of the association between myopia when defined as a spherical equivalent of -0.5D. The quality of the evidence is very low. Family History of POAG Three cross-sectional studies investigated the association between family history of glaucoma and prevalent POAG. These data suggest a 2.5 to 3.0 fold increase in the odds having POAG in persons with a family history (any first-degree relative) of POAG. The quality of the evidence is moderate. Age-Related Maculopathy Age Four cohort studies evaluated the association between age and early ARM and AMD. After 55 years of age, the incidence of both early ARM and AMD increases with increasing age. Progression to AMD occurs in up to 12% of persons with early ARM. The quality of the evidence is low Gender Four cohort studies evaluated the association between gender and early ARM and AMD. Gender differences in incident early ARM and incident AMD are not supported from these data. The quality of the evidence is lows. Ethnicity One meta-analysis and 2 cross-sectional studies reported the ethnic-specific prevalence rates of ARM. The data suggests that the prevalence of early ARM is higher in a white population compared with a black population. The data suggest that the ethnic-specific differences in the prevalence of AMD remain inconclusive. Refractive Error Two cohort studies investigated the association between refractive error and the development of incident early ARM and AMD. The quality of the evidence is very low. Family History Two cross-sectional studies evaluated the association of family history and early ARM and AMD. Data from one study supports an association between a positive family history of AMD and having AMD. The results of the study indicate an almost 4-fold increase in the odds of any AMD in a person with a family history of AMD. The quality of the evidence, as based on the GRADE criteria is moderate. Economic Analysis The prevalence of glaucoma is estimated at 1 to 3% for a Caucasian population and 4.2 to 8.8% for a black population. The incidence of glaucoma is estimated at 0.5 to 2.5% per year in the literature. The percentage of people who go blind per year as a result of glaucoma is approximately 0.55%. The total population of Ontarians aged 50 to 64 years is estimated at 2.6 million based on the April 2006 Ontario Ministry of Finance population estimates. The range of utilization for a major eye examination in 2006/07 for this age group is estimated at 567,690 to 669,125, were coverage for major eye exams extended to this age group. This would represent a net increase in utilization of approximately 440,116 to 541,551. The percentage of Ontario population categorized as black and/or those with a family history of glaucoma was approximately 20%. Therefore, the estimated range of utilization for a major eye examination in 2006/07 for this sub-population is estimated at 113,538 - 138,727 (20% of the estimated range of utilization in total population of 50-64 year olds in Ontario), were coverage for major eye exams extended to this sub-group. This would represent a net increase in utilization of approximately 88,023 to 108,310 within this sub-group. Costs The total cost of a major eye examination by a physician is $42.15, as per the 2006 Schedule of Benefits for Physician Services.(1) The total difference between the treatments of early-stage versus late-stage glaucoma was estimated at $167. The total cost per recipient was estimated at $891/person. Current Ontario Policy As of November 1, 2004 persons between 20 years and 64 years of age are eligible for an insured eye examination once every year if they have any of the following medical conditions: diabetes mellitus type 1 or 2, glaucoma, cataract(s), retinal disease, amblyopia, visual field defects, corneal disease, or strabismus. Persons between 20 to 64 years of age who do not have diabetes mellitus, glaucoma, cataract(s), retinal disease, amblyopia, visual field defects, corneal disease, or strabismus may be eligible for an annual eye examination if they have a valid “request for major eye examination” form completed by a physician (other than that who completed the eye exam) or a nurse practitioner working in a collaborative practice. Persons 20-64 years of age who are in receipt of social assistance and who do not have one of the 8 medical conditions listed above are eligible to receive an eye exam once every 2 years as a non-OHIP government funded service. Persons 19 years of age or younger and 65 years of age or older may receive an insured eye exam once every year. Considerations for Policy Development As of July 17, 2006 there were 1,402 practicing optometrists in Ontario. As of December 31, 2005 there were 404 practicing ophthalmologists in Ontario. It is unknown how many third party payers now cover routine eye exams for person between the ages of 20 and 64 years of age in Ontario. PMID:23074485

Diagnostic capability of scanning laser polarimetry with variable cornea compensator in Indian patients with early primary open-angle glaucoma.

PubMed

Parikh, Rajul S; Parikh, Shefali R; Kumar, Rajesh S; Prabakaran, S; Babu, J Gansesh; Thomas, Ravi

2008-07-01

To evaluate the diagnostic ability of scanning laser polarimetry (GDx variable corneal compensator [VCC]) for early glaucoma in Asian Indian eyes. Cross-sectional observational study. Two groups of patients (early glaucoma and normal) who satisfied the inclusion and exclusion criteria were included. Early glaucoma was diagnosed in presence of open angles, characteristic glaucomatous optic disc changes correlating with the visual field (VF) on automated perimetry (VF defect fulfilling at least 2 of 3 Anderson and Patella's criteria with mean deviation >or= -6 decibels). Normal subjects had visual acuity >or= 20/30 and intraocular pressure < 22 mmHg, with a normal optic disc and fields and no ocular abnormality. All patients underwent complete ophthalmic evaluation, including VF examination (24-2/30-2 Swedish interactive threshold algorithm standard program) and imaging with GDx VCC. Sensitivity, specificity, positive predictive value and negative predictive value, area under the receiving operating characteristic curve, and likelihood ratios (LRs) were calculated for various GDx VCC parameters. Seventy-four eyes (74 patients) with early glaucoma and 104 eyes (104 normal subjects) were enrolled. TSNIT Std Dev (temporal-superior-nasal-inferior-temporal standard deviation) had the best combination of sensitivity and specificity-61.3 and 95.2, respectively-followed by nerve fiber index score > 50 (sensitivity, 52.7%; specificity, 99%). Nerve fiber index score > 50 had positive and negative predictive values of 74.3% and 97.6%, respectively, for an assumed glaucoma prevalence of 5%. Nerve fiber index score > 50 had a positive LR (+LR) of 54.8 for early glaucoma. GDx VCC has moderate sensitivity, with high specificity, in the diagnosis of early glaucoma. The high +LR for the nerve fiber index score can provide valuable diagnostic information for individual patients.

Eye shape and the nocturnal bottleneck of mammals.

PubMed

Hall, Margaret I; Kamilar, Jason M; Kirk, E Christopher

2012-12-22

Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal 'bottleneck' in the early evolution of crown mammals.

Eye shape and the nocturnal bottleneck of mammals

PubMed Central

Hall, Margaret I.; Kamilar, Jason M.; Kirk, E. Christopher

2012-01-01

Most vertebrate groups exhibit eye shapes that vary predictably with activity pattern. Nocturnal vertebrates typically have large corneas relative to eye size as an adaptation for increased visual sensitivity. Conversely, diurnal vertebrates generally demonstrate smaller corneas relative to eye size as an adaptation for increased visual acuity. By contrast, several studies have concluded that many mammals exhibit typical nocturnal eye shapes, regardless of activity pattern. However, a recent study has argued that new statistical methods allow eye shape to accurately predict activity patterns of mammals, including cathemeral species (animals that are equally likely to be awake and active at any time of day or night). Here, we conduct a detailed analysis of eye shape and activity pattern in mammals, using a broad comparative sample of 266 species. We find that the eye shapes of cathemeral mammals completely overlap with nocturnal and diurnal species. Additionally, most diurnal and cathemeral mammals have eye shapes that are most similar to those of nocturnal birds and lizards. The only mammalian clade that diverges from this pattern is anthropoids, which have convergently evolved eye shapes similar to those of diurnal birds and lizards. Our results provide additional evidence for a nocturnal ‘bottleneck’ in the early evolution of crown mammals. PMID:23097513

Brain Mechanisms Involved in Early Visual Perception.

ERIC Educational Resources Information Center

Karmel, Bernard Z.

This document presents an analysis of the early attending responses and orienting reactions of infants which can be observed at birth and shortly thereafter. Focus is on one specific orienting reaction, the early direction and maintenance of one's eyes and head toward certain stimuli instead of others. The physical properties of stimuli that…

Controlled five-year follow-up study of laser trabeculoplasty as primary therapy for open-angle glaucoma

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

Tuulonen, A.; Niva, A.K.; Alanko, H.I.

1987-10-15

We followed up 32 eyes of 32 patients with early glaucoma (22 with capsular glaucoma and ten with simple glaucoma) who received laser trabeculoplasty as a primary therapy. These eyes were compared with a matched control group of 32 eyes treated with medication initially. The success rate (intraocular pressure below 22 mm Hg with laser alone or medication alone) at five years was 50% (16 of 32 eyes) in the laser-treated group and 22% (seven of 32 eyes) in the control group (P less than .02). The control group required more modifications of their therapy to control intraocular pressure. Themore » neuroretinal rim area in the control eyes decreased 2.5 times as much as in the laser group (P = .017). Changes in the Friedmann visual fields did not differ significantly between the two groups.« less

Dichoptic training enables the adult amblyopic brain to learn.

PubMed

Li, Jinrong; Thompson, Benjamin; Deng, Daming; Chan, Lily Y L; Yu, Minbin; Hess, Robert F

2013-04-22

Adults with amblyopia, a common visual cortex disorder caused primarily by binocular disruption during an early critical period, do not respond to conventional therapy involving occlusion of one eye. But it is now clear that the adult human visual cortex has a significant degree of plasticity, suggesting that something must be actively preventing the adult brain from learning to see through the amblyopic eye. One possibility is an inhibitory signal from the contralateral eye that suppresses cortical inputs from the amblyopic eye. Such a gating mechanism could explain the apparent lack of plasticity within the adult amblyopic visual cortex. Here we provide direct evidence that alleviating suppression of the amblyopic eye through dichoptic stimulus presentation induces greater levels of plasticity than forced use of the amblyopic eye alone. This indicates that suppression is a key gating mechanism that prevents the amblyopic brain from learning to see. Copyright © 2013 Elsevier Ltd. All rights reserved.

Affective empathy, cognitive empathy and social attention in children at high risk of criminal behaviour.

PubMed

van Zonneveld, Lisette; Platje, Evelien; de Sonneville, Leo; van Goozen, Stephanie; Swaab, Hanna

2017-08-01

Empathy deficits are hypothesized to underlie impairments in social interaction exhibited by those who engage in antisocial behaviour. Social attention is an essential precursor to empathy; however, no studies have yet examined social attention in relation to cognitive and affective empathy in those exhibiting antisocial behaviour. Participants were 8- to 12-year-old children at high risk of developing criminal behaviour (N = 114, 80.7% boys) and typically developing controls (N = 43, 72.1% boys). The high-risk children were recruited through an ongoing early identification and intervention project of the city of Amsterdam, focusing on the underage siblings or children of delinquents and those failing primary school. Video clips with neutral and emotional content (fear, happiness and pain) were shown, while heart rate (HR), skin conductance level (SCL) and skin conductance responses (SCRs) were recorded to measure affective empathy. Answers to questions about emotions in the clips were coded to measure cognitive empathy. Eye-tracking was used to evaluate visual scanning patterns towards social relevant cues (eyes and face) in the clips. The high-risk group did not differ from the control group in social attention and cognitive empathy, but showed reduced HR to pain and fear, and reduced SCL and SCRs to pain. Children at high risk of developing criminal behaviour show impaired affective empathy but unimpaired social attention and cognitive empathy. The implications for early identification and intervention studies with antisocial children are discussed. © 2017 Association for Child and Adolescent Mental Health.

The Potential Utility of Eye Movements in the Detection and Characterization of Everyday Functional Difficulties in Mild Cognitive Impairment.

PubMed

Seligman, Sarah C; Giovannetti, Tania

2015-06-01

Mild cognitive impairment (MCI) refers to the intermediate period between the typical cognitive decline of normal aging and more severe decline associated with dementia, and it is associated with greater risk for progression to dementia. Research has suggested that functional abilities are compromised in MCI, but the degree of impairment and underlying mechanisms remain poorly understood. The development of sensitive measures to assess subtle functional decline poses a major challenge for characterizing functional limitations in MCI. Eye-tracking methodology has been used to describe visual processes in everyday, naturalistic action among healthy older adults as well as several case studies of severely impaired individuals, and it has successfully differentiated healthy older adults from those with MCI on specific visual tasks. These studies highlight the promise of eye-tracking technology as a method to characterize subtle functional decline in MCI. However, to date no studies have examined visual behaviors during completion of naturalistic tasks in MCI. This review describes the current understanding of functional ability in MCI, summarizes findings of eye-tracking studies in healthy individuals, severe impairment, and MCI, and presents future research directions to aid with early identification and prevention of functional decline in disorders of aging.

Bidirectional Expression of Metabolic, Structural, and Immune Pathways in Early Myopia and Hyperopia

PubMed Central

Riddell, Nina; Giummarra, Loretta; Hall, Nathan E.; Crewther, Sheila G.

2016-01-01

Myopia (short-sightedness) affects 1.45 billion people worldwide, many of whom will develop sight-threatening secondary disorders. Myopic eyes are characterized by excessive size while hyperopic (long-sighted) eyes are typically small. The biological and genetic mechanisms underpinning the retina's local control of these growth patterns remain unclear. In the present study, we used RNA sequencing to examine gene expression in the retina/RPE/choroid across 3 days of optically-induced myopia and hyperopia induction in chick. Data were analyzed for differential expression of single genes, and Gene Set Enrichment Analysis (GSEA) was used to identify gene sets correlated with ocular axial length and refraction across lens groups. Like previous studies, we found few single genes that were differentially-expressed in a sign-of-defocus dependent manner (only BMP2 at 1 day). Using GSEA, however, we are the first to show that more subtle shifts in structural, metabolic, and immune pathway expression are correlated with the eye size and refractive changes induced by lens defocus. Our findings link gene expression with the morphological characteristics of refractive error, and suggest that physiological stress arising from metabolic and inflammatory pathway activation could increase the vulnerability of myopic eyes to secondary pathologies. PMID:27625591

Personalized ophthalmology

PubMed Central

Porter, LF; Black, GCM

2014-01-01

Porter L.F., Black G.C.M. Personalized ophthalmology. Clin Genet 2014: 86: 1–11. © 2014 The Authors. Clinical Genetics published by John Wiley & Sons A/S. Published by John Wiley & Sons Ltd., 2014 Ophthalmology has been an early adopter of personalized medicine. Drawing on genomic advances to improve molecular diagnosis, such as next-generation sequencing, and basic and translational research to develop novel therapies, application of genetic technologies in ophthalmology now heralds development of gene replacement therapies for some inherited monogenic eye diseases. It also promises to alter prediction, diagnosis and management of the complex disease age-related macular degeneration. Personalized ophthalmology is underpinned by an understanding of the molecular basis of eye disease. Two important areas of focus are required for adoption of personalized approaches: disease stratification and individualization. Disease stratification relies on phenotypic and genetic assessment leading to molecular diagnosis; individualization encompasses all aspects of patient management from optimized genetic counseling and conventional therapies to trials of novel DNA-based therapies. This review discusses the clinical implications of these twin strategies. Advantages and implications of genetic testing for patients with inherited eye diseases, choice of molecular diagnostic modality, drivers for adoption of personalized ophthalmology, service planning implications, ethical considerations and future challenges are considered. Indeed, whilst many difficulties remain, personalized ophthalmology truly has the potential to revolutionize the specialty. PMID:24665880

Comparison of macular choroidal thickness among patients older than age 65 with early atrophic age-related macular degeneration and normals.

PubMed

Sigler, Eric J; Randolph, John C

2013-09-19

To compare macular choroidal thickness between patients older than 65 years with early atrophic age-related macular degeneration (AMD) and normals. This was a consecutive, cross-sectional observational study. Enhanced depth imaging spectral-domain optical coherence tomography using horizontal raster scanning at 12 locations throughout the macula was performed in one eye of consecutive patients presenting with large soft drusen alone, drusen with additional features of early AMD, or a normal fundus. Choroidal thickness was measured at 7 points for each raster scan in the central 3 mm of the macula (total 84 points per eye). In addition, a single subfoveolar measurement was obtained for each eye. One hundred fifty eyes of 150 patients were included. There was no significant difference between mean refractive error for each diagnosis category via one-way ANOVA (P = 0.451). Mean macular choroidal thickness (CT) was 235 ± 49 μm (range, 125-334 μm; median 222 μm) for normals, 161 ± 39 μm (range, 89-260 μm; median = 158 μm) for the drusen group, and 115 ± 40 μm (range, 22-256 μm; median = 112 μm) for patients with AMD. Mean macular CT was significantly different via one-way ANOVA among all diagnosis categories (P < 0.001). The presence of features of early AMD without geographic atrophy and/or soft drusen alone is associated with decreased mean macular CT in vivo compared to that in patients with no chorioretinal pathology. Using enhanced depth imaging, measurement of a single subfoveolar choroidal thickness is highly correlated to mean central macular CT.

Dynamic Eye Tracking Based Metrics for Infant Gaze Patterns in the Face-Distractor Competition Paradigm

PubMed Central

Ahtola, Eero; Stjerna, Susanna; Yrttiaho, Santeri; Nelson, Charles A.; Leppänen, Jukka M.; Vanhatalo, Sampsa

2014-01-01

Objective To develop new standardized eye tracking based measures and metrics for infants’ gaze dynamics in the face-distractor competition paradigm. Method Eye tracking data were collected from two samples of healthy 7-month-old (total n = 45), as well as one sample of 5-month-old infants (n = 22) in a paradigm with a picture of a face or a non-face pattern as a central stimulus, and a geometric shape as a lateral stimulus. The data were analyzed by using conventional measures of infants’ initial disengagement from the central to the lateral stimulus (i.e., saccadic reaction time and probability) and, additionally, novel measures reflecting infants gaze dynamics after the initial disengagement (i.e., cumulative allocation of attention to the central vs. peripheral stimulus). Results The results showed that the initial saccade away from the centrally presented stimulus is followed by a rapid re-engagement of attention with the central stimulus, leading to cumulative preference for the central stimulus over the lateral stimulus over time. This pattern tended to be stronger for salient facial expressions as compared to non-face patterns, was replicable across two independent samples of 7-month-old infants, and differentiated between 7 and 5 month-old infants. Conclusion The results suggest that eye tracking based assessments of infants’ cumulative preference for faces over time can be readily parameterized and standardized, and may provide valuable techniques for future studies examining normative developmental changes in preference for social signals. Significance Standardized measures of early developing face preferences may have potential to become surrogate biomarkers of neurocognitive and social development. PMID:24845102

Effects of increased temperature on metabolic activity and oxidative stress in the first life stages of marble trout (Salmo marmoratus).

PubMed

Simčič, Tatjana; Jesenšek, Dušan; Brancelj, Anton

2015-08-01

Climate change may result in future alterations in thermal regime which could markedly affect the early developmental stages of cold water fish due to their expected high sensitivity to increasing temperature. In the present study, the effect of temperature increase of 2, 4 and 6°C on the oxygen consumption rate (R), the activity of respiratory electron transport system (ETS) and oxidative stress have been studied in four developmental stages of the marble trout (Salmo marmoratus)-eyed eggs, yolk-sac larvae and juveniles of 1 and 3 months. Oxygen consumption rate and ETS activity increased with level of development and with temperature in all four stages. ETS/R ratios decreased during development and correlated with temperature in eyed eggs, larvae and juveniles of 1 month, but not in juveniles of 3 months. Low ETS/R ratios at higher temperatures indicate stress response in eyed eggs, the most temperature sensitive developmental stage. Catalase (CAT) and glutathione reductase (GR) activities increased during development, but responded differently to elevated temperature in the different developmental stages. Stress in eyed eggs, caused by higher temperatures, resulted in increased oxygen consumption rate and increased activities of CAT and GR. Larvae were sensitive to increased temperature only at the highest experimental temperature of 16°C. Increased temperature did not stress the metabolism of the juveniles, since they were able to compensate their metabolic activity. The earlier developmental stages of marble trout are thus more sensitive to temperature increase than juveniles and therefore more endangered by higher water temperatures. This is the first report connecting oxygen consumption, ETS activity and ETS/R ratio with the activities of antioxidant enzymes in relation to increased temperature in salmonids.

Scientists repurpose HPV vaccine technology to fight eye cancer | Center for Cancer Research

Cancer.gov

Uveal melanoma is a rare eye cancer that affects about 1,600 people in the United States. A study by scientists in the Center for Cancer Research and Aura Biosciences, Cambridge, Mass., published December 14, 2017, in Molecular Cancer Therapeutics, provides new hope for the early treatment of uveal melanoma. Read more…

Semantic Evaluation of Syntactic Structure: Evidence from Eye Movements

ERIC Educational Resources Information Center

Frazier, Lyn; Carminati, Maria Nella; Cook, Anne E.; Majewski, Helen; Rayner, Keith

2006-01-01

An eye movement study of temporarily ambiguous closure sentences confirmed that the early closure penalty in a sentence like "While John hunted the frightened deer escaped" is larger for a simple past verb ("hunted") than for a past progressive verb ("was hunting"). The results can be explained by the observation that simple past tense verbs…

Anterior ocular abnormalities of captive Asian elephants (Elephas maximus indicus) in Thailand.

PubMed

Kraiwong, Natapong; Sanyathitiseree, Pornchai; Boonprasert, Khajohnpat; Diskul, Phiphatanachatr; Charoenphan, Patara; Pintawong, Weerasak; Thayananuphat, Aree

2016-07-01

To survey and classify anterior ocular abnormalities in 1478 captive Asian elephants (Elephas maximus indicus) in six regions of Thailand. Anterior ocular examination was performed in both eyes (n = 2956) of 1478 elephants selected from the annual health check program involving 2958 animals within six regions of Thailand from January to November 2013. Lesions were described and compared between age and gender. A total of 17.83% (527/2956) of examined eyes from 24.97% (369/1478) of examined elephants had anterior ocular abnormalities. The most common lesions in these examined eyes were frothy ocular discharge (5.85%), corneal edema (5.31%), and conjunctivitis (5.18%). In addition, epiphora, phthisis bulbi, other corneal abnormalities, anterior uveitis, and lens abnormalities were noted. Almost all lesions increased in frequency with age (P < 0.01). Regular ophthalmic examination in elephants should be included in their annual health check program. Early detection and treatment of any ocular abnormality may avoid the development of subsequent irreversible ocular pathology. © 2015 American College of Veterinary Ophthalmologists.

Second harmonic generation microscopy of the living human cornea

NASA Astrophysics Data System (ADS)

Artal, Pablo; Ávila, Francisco; Bueno, Juan

2018-02-01

Second Harmonic Generation (SHG) microscopy provides high-resolution structural imaging of the corneal stroma without the need of labelling techniques. This powerful tool has never been applied to living human eyes so far. Here, we present a new compact SHG microscope specifically developed to image the structural organization of the corneal lamellae in living healthy human volunteers. The research prototype incorporates a long-working distance dry objective that allows non-contact three-dimensional SHG imaging of the cornea. Safety assessment and effectiveness of the system were firstly tested in ex-vivo fresh eyes. The maximum average power of the used illumination laser was 20 mW, more than 10 times below the maximum permissible exposure (according to ANSI Z136.1-2000). The instrument was successfully employed to obtain non-contact and non-invasive SHG of the living human eye within well-established light safety limits. This represents the first recording of in vivo SHG images of the human cornea using a compact multiphoton microscope. This might become an important tool in Ophthalmology for early diagnosis and tracking ocular pathologies.

Fly's Eye camera system: optical imaging using a hexapod platform

NASA Astrophysics Data System (ADS)

Jaskó, Attila; Pál, András.; Vida, Krisztián.; Mészáros, László; Csépány, Gergely; Mező, György

2014-07-01

The Fly's Eye Project is a high resolution, high coverage time-domain survey in multiple optical passbands: our goal is to cover the entire visible sky above the 30° horizontal altitude with a cadence of ~3 min. Imaging is going to be performed by 19 wide-field cameras mounted on a hexapod platform resembling a fly's eye. Using a hexapod developed and built by our team allows us to create a highly fault-tolerant instrument that uses the sky as a reference to define its own tracking motion. The virtual axis of the platform is automatically aligned with the Earth's rotational axis; therefore the same mechanics can be used independently from the geographical location of the device. Its enclosure makes it capable of autonomous observing and withstanding harsh environmental conditions. We briefly introduce the electrical, mechanical and optical design concepts of the instrument and summarize our early results, focusing on sidereal tracking. Due to the hexapod design and hence the construction is independent from the actual location, it is considerably easier to build, install and operate a network of such devices around the world.

Current trends in the monitoring and treatment of diabetic retinopathy in young adults.

PubMed

Raczyńska, Dorota; Zorena, Katarzyna; Urban, Beata; Zalewski, Dominik; Skorek, Andrzej; Malukiewicz, Grażyna; Sikorski, Bartosz L

2014-01-01

The diagnosis and treatment of diabetic retinopathy (DR) in young adults have significantly improved in recent years. Research methods have widened significantly, for example, by introducing spectral optical tomography of the eye. Invasive diagnostics, for example, fluorescein angiography, are done less frequently. The early introduction of an insulin pump to improve the administration of insulin is likely to delay the development of diabetic retinopathy, which is particularly important for young patients with type 1 diabetes mellitus (T1DM). The first years of diabetes occurring during childhood and youth are the most appropriate to introduce proper therapeutic intervention before any irreversible changes in the eyes appear. The treatment of DR includes increased metabolic control, laserotherapy, pharmacological treatment (antiangiogenic and anti-inflammatory treatment, enzymatic vitreolysis, and intravitreal injections), and surgery. This paper summarizes the up-to-date developments in the diagnostics and treatment of DR. In the literature search, authors used online databases, PubMed, and clinitrials.gov and browsed through individual ophthalmology journals, books, and leading pharmaceutical company websites.

Effects of orthographic consistency on eye movement behavior: German and English children and adults process the same words differently.

PubMed

Rau, Anne K; Moll, Kristina; Snowling, Margaret J; Landerl, Karin

2015-02-01

The current study investigated the time course of cross-linguistic differences in word recognition. We recorded eye movements of German and English children and adults while reading closely matched sentences, each including a target word manipulated for length and frequency. Results showed differential word recognition processes for both developing and skilled readers. Children of the two orthographies did not differ in terms of total word processing time, but this equal outcome was achieved quite differently. Whereas German children relied on small-unit processing early in word recognition, English children applied small-unit decoding only upon rereading-possibly when experiencing difficulties in integrating an unfamiliar word into the sentence context. Rather unexpectedly, cross-linguistic differences were also found in adults in that English adults showed longer processing times than German adults for nonwords. Thus, although orthographic consistency does play a major role in reading development, cross-linguistic differences are detectable even in skilled adult readers. Copyright © 2014 Elsevier Inc. All rights reserved.

Detecting Plant Stress

NASA Technical Reports Server (NTRS)

2001-01-01

Through an exclusive patent license from NASA Stennis Space Center, Spectrum Technologies, Inc., has developed a hand-held tool that helps farmers, foresters and other growers detect unhealthy crops before the human eye can see the damage. Developed by two NASA researchers, the Observer,TM shows the viewer which plants are under stress through multispectral imaging, a process that uses specific wavelengths of the light spectrum to obtain information about objects-in this case, plants. With this device, several wavelengths of light collect information about the plant and results are immediately processed and displayed. NASA research found that previsible signs of stress, such as such as a lack of nutrients, insufficient water, disease, or insect damage, can be detected by measuring the chlorophyll content based on light energy reflected from the plant. The Observer detects stress up to 16 days before deterioration is visible to the eye. Early detection provides an opportunity to reverse stress and save the plant. The hand-held, easily operated unit works in both natural and artificial light, making it suitable for outdoor or indoor planting.

[Recurrent corneal edema without ocular hypertension, pigment degeneration combined with deafness, progressive dystrophy of the outer eye-muscles in a patient with proportional dwarfism and diabetes mellitus (author's transl)].

PubMed

Käfer, O

1977-04-22

A 27-year-old woman has been suffering from recurrent corneal edema without ocular hypertension since her early childhood. When the cornea is clear, visual acuity-with correction for high myopia-is 5/10 to 5/15 and Nieden I; when the cornea is swollen, it decrease to 5/50 and 1/10, respectively, and Nieden VII. Furthermore, there is an atypical pigment degeneration of the retina combined with deafness, a progressive ptosis since her 10th year of life, and a progressive dystrophy of the outer eye muscles, having developed in the past few years. In addition, the mentally normal developed patient presents a proportional dwarfism (no dysostosis) and a diabetes mellitus. This combination of symptoms is compared with the well known Bardet-Biedl syndrome and the De Grouchy syndrome and is found to constitute a new syndrome.

How do adults and teens with self-declared Autism Spectrum Disorder experience eye contact? A qualitative analysis of first-hand accounts

PubMed Central

Roberts, Nicole; Lin, Cathy; Birmingham, Elina

2017-01-01

A tendency to avoid eye contact is an early indicator of Autism Spectrum Disorder (ASD), and difficulties with eye contact often persist throughout the lifespan. Eye contact difficulties may underlie social cognitive deficits in ASD, and can create significant social and occupational barriers. Thus, this topic has received substantial research and clinical attention. In this study, we used qualitative methods to analyze self-reported experiences with eye contact as described by teens and adults with self-declared ASD. Results suggest people with a self- declared ASD diagnosis experience adverse emotional and physiological reactions, feelings of being invaded, and sensory overload while making eye contact, in addition to difficulties understanding social nuances, and difficulties receiving and sending nonverbal information. Some data support existing mindblindness frameworks, and hyperarousal or hypoarousal theories of eye contact, but we also present novel findings unaccounted for by existing frameworks. Additionally, we highlight innovative strategies people with self-declared ASD have devised to overcome or cope with their eye contact difficulties. PMID:29182643

Comparison of Glaucoma Progression Detection by Optical Coherence Tomography and Visual Field.

PubMed

Zhang, Xinbo; Dastiridou, Anna; Francis, Brian A; Tan, Ou; Varma, Rohit; Greenfield, David S; Schuman, Joel S; Huang, David

2017-12-01

To compare longitudinal glaucoma progression detection using optical coherence tomography (OCT) and visual field (VF). Validity assessment. We analyzed subjects with more than 4 semi-annual follow-up visits (every 6 months) in the multicenter Advanced Imaging for Glaucoma Study. Fourier-domain optical coherence tomography (OCT) was used to map the thickness of the peripapillary retinal nerve fiber layer (NFL) and ganglion cell complex (GCC). OCT-based progression detection was defined as a significant negative trend for either NFL or GCC. VF progression was reached if either the event or trend analysis reached significance. The analysis included 356 glaucoma suspect/preperimetric glaucoma (GS/PPG) eyes and 153 perimetric glaucoma (PG) eyes. Follow-up length was 54.1 ± 16.2 months for GS/PPG eyes and 56.7 ± 16.0 for PG eyes. Progression was detected in 62.1% of PG eyes and 59.8% of GS/PPG eyes by OCT, significantly (P < .001) more than the detection rate of 41.8% and 27.3% by VF. In severity-stratified analysis of PG eyes, OCT had significantly higher detection rate than VF in mild PG (63.1% vs. 38.7%, P < .001), but not in moderate and advanced PG. The rate of NFL thinning slowed dramatically in advanced PG, but GCC thinning rate remained relatively steady and allowed good progression detection even in advanced disease. The Kaplan-Meier time-to-event analyses showed that OCT detected progression earlier than VF in both PG and GS/PPG groups. OCT is more sensitive than VF for the detection of progression in early glaucoma. While the utility of NFL declines in advanced glaucoma, GCC remains a sensitive progression detector from early to advanced stages. Copyright © 2017 Elsevier Inc. All rights reserved.

Staging of Macular Telangiectasia: Power-Doppler Optical Coherence Tomography and Macular Pigment Optical Density

PubMed Central

Chin, Eric K.; Kim, Dae Yu; Hunter, Allan A.; Pilli, Suman; Wilson, Machelle; Zawadzki, Robert J.; Werner, John S.; Park, Susanna S.

2013-01-01

Purpose. Two methods were used to study the stages of macular telangiectasia (MacTel): Power-Doppler optical coherence tomography (PD-OCT), which allows imaging of the retinal circulation in three dimensions, and macular pigment optical density (MPOD), which quantifies the distribution of macular carotenoids. Methods. Among 49 patients with MacTel identified, 12 eyes (6 patients) with MacTel and 7 age-matched control eyes (7 patients) were imaged with a custom-built Fourier-domain OCT instrument to acquire PD-OCT images. MPOD was measured using heterochromatic flicker photometry in 10 eyes (5 patients) with MacTel and compared with 44 age-matched control eyes (44 patients). Clinical staging of MacTel was based on best-corrected visual acuity, fundus biomicroscopy, fluorescein angiography, and OCT. Results. Stage 1 eyes (n = 2) had subtle punctate vascular signal confined to the inner portion of the outer plexiform layer (OPL) on PD-OCT. Stage 2 (n = 2) showed larger oblique vascular signal extending into deeper OPL. Stage 3 (n = 5) had disruption of outer retinal layers with abnormal vasculature extending into the outer nuclear layer. Stage 4 (n = 3) showed diffuse blurring of the retinal layers with vascular channels extending the full thickness of the retina. MPOD values in four eyes with stage 1 or 2 MacTel correlated well with age-matched controls. Six eyes with stage 3 or 4 MacTel had loss of MPOD especially at the fovea. Conclusions. PD-OCT shows penetration of the retinal capillaries into the deeper retinal layers in early stages of MacTel, with full thickness vascular proliferation in advanced disease. MPOD is commonly depleted but may appear normal in early stage MacTel. PMID:23716628

Incidence and risk factors for chronic uveitis following cataract surgery.

PubMed

Patel, Chirag; Kim, Stephen Jae; Chomsky, Amy; Saboori, Mazeyar

2013-04-01

To determine the incidence of and associated risk factors for uveitis after cataract surgery. A total of 17,757 eyes were identified and records of 42 eyes that developed uveitis and 2320 eyes that did not were reviewed. Postsurgical uveitis was defined as persistent inflammation for ≥ 6 months after surgery. Forty-two eyes of 35 patients developed uveitis (0.24%). Eleven patients underwent consecutive cataract surgery but developed unilateral uveitis, and intraoperative complications occurred in 55% of uveitic eyes compared to 0% in fellow eyes (p < 0.05). Median duration of inflammation was 8 and 11.5 months in eyes with and without vitrectomy (p < 0.05). Intraocular complications occurred in 44 and 8.3% of eyes that did and did not develop uveitis, respectively (p = 0.01). Postsurgical uveitis developed after approximately 1 in 400 cataract surgeries and occurred more frequently in eyes experiencing intraoperative complications.

New therapeutic modality for corneal endothelial disease using Rho-associated kinase inhibitor eye drops.

PubMed

Koizumi, Noriko; Okumura, Naoki; Ueno, Morio; Kinoshita, Shigeru

2014-11-01

Corneal endothelial dysfunction accompanied by visual disturbance is a primary indication for corneal endothelial transplantation. However, despite the value and potential of endothelial graft surgery, a strictly pharmacological approach for treating corneal endothelial dysfunction remains an attractive proposition. Previously, we reported that the selective Rho-associated kinase (ROCK) inhibitor Y-27632 promotes cell adhesion and proliferation, and inhibits the apoptosis of primate corneal endothelial cells in culture. These findings have led us to develop a novel medical treatment for the early phase of corneal endothelial disease using ROCK inhibitor eye drops. In rabbit and monkey models of partial endothelial dysfunction, we showed that corneal endothelial wound healing was accelerated via the topical application of ROCK inhibitor to the ocular surface, resulting in the regeneration of a corneal endothelial monolayer with a high endothelial cell density. Based on these animal studies, we are now attempting to advance the clinical application of ROCK inhibitor eye drops for patients with corneal endothelial dysfunction. A pilot clinical study was performed at the Kyoto Prefectural University of Medicine, and the effects of Y-27632 eye drops after transcorneal freezing were evaluated in 8 patients with corneal endothelial dysfunction. We observed a positive effect of ROCK inhibitor eye drops in treating patients with central edema caused by Fuchs corneal endothelial dystrophy. We believe that our new findings will contribute to the establishment of a new approach for the treatment of corneal endothelial dysfunction.

Senior Leadership - The Crucial Element of Combat Power: A Leadership Analysis of Selected World War II Commanders, European Theater, 1944-45.

DTIC Science & Technology

1984-05-07

70 Analysis of General Simpson’s Management ...... 76 4. In the Eye of the Hurricane - Major General Troy Houston Middleton...promoted to four star rank on the retired list in 1954. He died in 1980 at the age of ninety-two. 90 CHAPTER 4 IN THE EYE OF THE HURRICANE - MAJOR GENERAL...while in the eye of this man-made hurricane that will stand as his greatest achievement. Background and Early Career of General Middleton: 1889-1944

Combining psychological and engineering approaches to utilizing social robots with children with autism.

PubMed

Dickstein-Fischer, Laurie; Fischer, Gregory S

2014-01-01

It is estimated that Autism Spectrum Disorder (ASD) affects 1 in 68 children. Early identification of an ASD is exceedingly important to the introduction of an intervention. We are developing a robot-assisted approach that will serve as an improved diagnostic and early intervention tool for children with autism. The robot, named PABI® (Penguin for Autism Behavioral Interventions), is a compact humanoid robot taking on an expressive cartoon-like embodiment. The robot is affordable, durable, and portable so that it can be used in various settings including schools, clinics, and the home. Thus enabling significantly enhanced and more readily available diagnosis and continuation of care. Through facial expressions, body motion, verbal cues, stereo vision-based tracking, and a tablet computer, the robot is capable of interacting meaningfully with an autistic child. Initial implementations of the robot, as part of a comprehensive treatment model (CTM), include Applied Behavioral Analysis (ABA) therapy where the child interacts with a tablet computer wirelessly interfaced with the robot. At the same time, the robot makes meaningful expressions and utterances and uses stereo cameras in eyes to track the child, maintain eye contact, and collect data such as affect and gaze direction for charting of progress. In this paper we present the clinical justification, anticipated usage with corresponding requirements, prototype development of the robotic system, and demonstration of a sample application for robot-assisted ABA therapy.

Delineation of a spatial working memory profile using a non-verbal eye-tracking paradigm in young children with autism and Williams syndrome.

PubMed

Fanning, Peter A J; Hocking, Darren R; Dissanayake, Cheryl; Vivanti, Giacomo

2018-05-01

Working memory deficits profoundly inhibit children's ability to learn. While deficits have been identified in disorders such as autism spectrum disorder (ASD) and Williams syndrome (WS), findings are equivocal, and very little is known about the nature of these deficits early in development. A major barrier to advances in this area is the availability of tasks suitable for young children with neurodevelopmental disorders who experience difficulties with following verbal instructions or who are distressed by formal testing demands. To address these issues, a novel eye-tracking paradigm was designed based on an adaptation of the classic A not B paradigm in order to examine the early foundations of spatial working memory capabilities in 26 developmentally delayed preschool children with ASD, 18 age- and IQ-matched children with WS, and 19 age-matched typically-developing (TD) children. The results revealed evidence that foundational spatial working memory performance in ASD and WS was comparable with that of TD children. Performance was associated with intellectual ability in the ASD and TD groups, but not in the WS group. Performance was not associated with adaptive behavior in any group. These findings are discussed in the context of previous research that has been largely limited to older and substantially less developmentally delayed children with these neurodevelopmental disorders.

Variable corneal compensation improves discrimination between normal and glaucomatous eyes with the scanning laser polarimeter.

PubMed

Tannenbaum, Dana P; Hoffman, Douglas; Lemij, Hans G; Garway-Heath, David F; Greenfield, David S; Caprioli, Joseph

2004-02-01

The presently available scanning laser polarimeter (SLP) has a fixed corneal compensator (FCC) that neutralizes corneal birefringence only in eyes with birefringence that matches the population mode. A prototype variable corneal compensator (VCC) provides neutralization of individual corneal birefringence based on individual macular retardation patterns. The aim of this study was to evaluate the relative ability of the SLP with the FCC and with the VCC to discriminate between normal and glaucomatous eyes. Prospective, nonrandomized, comparative case series. Algorithm-generating set consisting of 56 normal eyes and 55 glaucomatous eyes and an independent data set consisting of 83 normal eyes and 56 glaucomatous eyes. Sixteen retardation measurements were obtained with the SLP with the FCC and the VCC from all subjects. Dependency of parameters on age, gender, ethnic origin, and eye side was sought. Logistic regression was used to evaluate how well the various parameters could detect glaucoma. Discriminant functions were generated, and the area under the receiver operating characteristic (ROC) curve was determined. Discrimination between normal and glaucomatous eyes on the basis of single parameters was significantly better with the VCC than with the FCC for 6 retardation parameters: nasal average (P = 0.0003), superior maximum (P = 0.0003), ellipse average (P = 0.002), average thickness (P = 0.003), superior average (P = 0.010), and inferior average (P = 0.010). Discriminant analysis identified the optimal combination of parameters for the FCC and for the VCC. When the discriminant functions were applied to the independent data set, areas under the ROC curve were 0.84 for the FCC and 0.90 for the VCC (P<0.021). When the discriminant functions were applied to a subset of patients with early visual field loss, areas under the ROC curve were 0.82 for the FCC and 0.90 for the VCC (P<0.016). Individual correction for corneal birefringence with the VCC significantly improved the ability of the SLP to distinguish between normal and glaucomatous eyes and enabled detection of patients with early glaucoma.

The effect of maternal diabetes on the Wnt-PCP pathway during embryogenesis as reflected in the developing mouse eye

PubMed Central

López-Escobar, Beatriz; Cano, David A.; Rojas, Anabel; de Felipe, Beatriz; Palma, Francisco; Sánchez-Alcázar, José A.; Henderson, Deborah; Ybot-González, Patricia

2015-01-01

Embryopathies that develop as a consequence of maternal diabetes have been studied intensely in both experimental and clinical scenarios. Accordingly, hyperglycaemia has been shown to downregulate the expression of elements in the non-canonical Wnt-PCP pathway, such as the Dishevelled-associated activator of morphogenesis 1 (Daam1) and Vangl2. Daam1 is a formin that is essential for actin polymerization and for cytoskeletal reorganization, and it is expressed strongly in certain organs during mouse development, including the eye, neural tube and heart. Daam1gt/gt and Daam1gt/+ embryos develop ocular defects (anophthalmia or microphthalmia) that are similar to those detected as a result of hyperglycaemia. Indeed, studying the effects of maternal diabetes on the Wnt-PCP pathway demonstrated that there was strong association with the Daam1 genotype, whereby the embryopathy observed in Daam1gt/+ mutant embryos of diabetic dams was more severe. There was evidence that embryonic exposure to glucose in vitro diminishes the expression of genes in the Wnt-PCP pathway, leading to altered cytoskeletal organization, cell shape and cell polarity in the optic vesicle. Hence, the Wnt-PCP pathway appears to influence cell morphology and cell polarity, events that drive the cellular movements required for optic vesicle formation and that, in turn, are required to maintain the fate determination. Here, we demonstrate that the Wnt-PCP pathway is involved in the early stages of mouse eye development and that it is altered by diabetes, provoking the ocular phenotype observed in the affected embryos. PMID:25540130

EYE DEVELOPMENT

PubMed Central

Baker, Nicholas E.; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

2014-01-01

The eye has been one of the most intensively studied organs in Drosophila. The wealth of knowledge about its development, as well as the reagents that have been developed, and the fact that the eye is dispensable for survival, also make the eye suitable for genetic interaction studies and genetic screens. This chapter provides a brief overview of the methods developed to image and probe eye development at multiple developmental stages, including live imaging, immunostaining of fixed tissues, in situ hybridizations, and scanning electron microscopy and color photography of adult eyes. Also summarized are genetic approaches that can be performed in the eye, including mosaic analysis and conditional mutation, gene misexpression and knockdown, and forward genetic and modifier screens. PMID:24784530

Robot Competence Development by Constructive Learning

NASA Astrophysics Data System (ADS)

Meng, Q.; Lee, M. H.; Hinde, C. J.

This paper presents a constructive learning approach for developing sensor-motor mapping in autonomous systems. The system’s adaptation to environment changes is discussed and three methods are proposed to deal with long term and short term changes. The proposed constructive learning allows autonomous systems to develop network topology and adjust network parameters. The approach is supported by findings from psychology and neuroscience especially during infants cognitive development at early stages. A growing radial basis function network is introduced as a computational substrate for sensory-motor mapping learning. Experiments are conducted on a robot eye/hand coordination testbed and results show the incremental development of sensory-motor mapping and its adaptation to changes such as in tool-use.

Robot Competence Development by Constructive Learning

NASA Astrophysics Data System (ADS)

Meng, Q.; Lee, M. H.; Hinde, C. J.

This paper presents a constructive learning approach for developing sensor-motor mapping in autonomous systems. The system's adaptation to environment changes is discussed and three methods are proposed to deal with long term and short term changes. The proposed constructive learning allows autonomous systems to develop network topology and adjust network parameters. The approach is supported by findings from psychology and neuroscience especially during infants cognitive development at early stages. A growing radial basis function network is introduced as a computational substrate for sensory-motor mapping learning. Experiments are conducted on a robot eye/hand coordination testbed and results show the incremental development of sensory-motor mapping and its adaptation to changes such as in tool-use.

Sensitivity and specificity of scanning laser polarimetry using the GDx.

PubMed

Munkwitz, S; Funk, J; Loeffler, K U; Harbarth, U; Kremmer, S

2004-09-01

To determine the sensitivity and the specificity of the GDx in the detection of (1) advanced glaucoma, (2) early glaucoma, and (3) nerve fibre bundle defects (NFBD). Group A comprised 20 eyes with reproducible glaucomatous visual field defects confirmed by octopus perimetry, group B consisted of 10 eyes with normal visual fields but either glaucomatous NFBD or deterioration of the disc over time clearly visible upon flicker comparison, and group C included 16 eyes with glaucomatous or non-glaucomatous NFBD clearly visible on red free photographs. Forty four eyes of 22 healthy volunteers served as controls. The GDx printouts of all subjects were evaluated by three independent observers in a masked fashion and without the clinical picture of the optic disc. Two of the three observers (SK, UH) were GDx experts, one (KUL) was an untrained GDx user. Among the GDx experts, sensitivity/specificity was 100%/100% (SK) and 90%/100% (UH) in detecting advanced glaucoma, and 100%/100% (SK) and 90%/100% (UH) in detecting early glaucoma. The sensitivity in detecting NFBD was only 37.5% (SK and UH). For the untrained GDx user the corresponding values were 50%/100% (group A), 20%/100% (group B), and 12.5%/91% (group C). Detection of (early) glaucoma damage by the GDx, evaluated by trained experts, can be extremely high. To optimise its benefit in clinical routine training in interpreting GDx printouts is highly recommended. Detection of localised NFBD is crucial, even for experts.

Modification of visual function by early visual experience.

PubMed

Blakemore, C

1976-07-01

Physiological experiments, involving recording from the visual cortex in young kittens and monkeys, have given new insight into human developmental disorders. In the visual cortex of normal cats and monkeys most neurones are selectively sensitive to the orientation of moving edges and they receive very similar signals from both eyes. Even in very young kittens without visual experience, most neurones are binocularly driven and a small proportion of them are genuinely orientation selective. There is no passive maturation of the system in the absence of visual experience, but even very brief exposure to patterned images produces rapid emergence of the adult organization. These results are compared to observations on humans who have "recovered" from early blindness. Covering one eye in a kitten or a monkey, during a sensitive period early in life, produces a virtually complete loss of input from that eye in the cortex. These results can be correlated with the production of "stimulus deprivation amblyopia" in infants who have had one eye patched. Induction of a strabismus causes a loss of binocularity in the visual cortex, and in humans it leads to a loss of stereoscopic vision and binocular fusion. Exposing kittens to lines of one orientation modifies the preferred orientations of cortical cells and there is an analogous "meridional amblyopia" in astigmatic humans. The existence of a sensitive period in human vision is discussed, as well as the possibility of designing remedial and preventive treatments for human developmental disorders.

Infants’ Behavioral Styles in Joint Attention Situations and Parents’ Socio-economic Status

PubMed Central

Second, Monika Abels; Hutman, Ted

2016-01-01

In this study the eco-cultural model of parenting (Keller, 2007) was applied to the study of joint attention behavior of children from families with different socioeconomic status (SES). It was hypothesized that infants’ early communication styles would differ with SES reflecting more independent or interdependent interactions with their caregivers. It was also hypothesized that infants would use the same types of behaviors whether they have declarative or imperative communication goals. The Early Social Communication Scales (ESCS, Mundy et al., 2003) was administered to 103 typically developing infants of 12 months (half of them siblings of children with autism). A factor analysis, yielding four behavioral factors, namely pointing, eye contact, actions and following points, confirmed the hypothesis that infants use behaviors consistently across situations independent of their communicative intent. MANOVAs (comprising parental education and income) Revealed that higher SES infants showed actions more frequently in the ESCS whereas lower SES infants followed experimenter’s points more frequently. The results are discussed in the context of presumably differing socialization goals for infants and the divergent contribution of parental education and income that seem to have additive contribution to some factors (actions, following points) but divergent contributions to others (pointing, eye contact). PMID:26164418

Expression of growth hormone gene during early development of Siberian sturgeon (Acipenser baerii)

PubMed Central

Abdolahnejad, Zeinab; Pourkazemi, Mohammad; Khoshkholgh, Majid Reza; Yarmohammadi, Mahtab

2015-01-01

The mRNA expression of growth hormone (GH) gene in early development stages of Siberian sturgeon was investigated using RT-PCR method. Samples were collected from unfertilized eggs up to 50 days post hatched (dph) larvae in 11 different times. Ribosomal protein L6 (RPL6) transcripts were used as the internal standard during quantification of GH mRNA expression. The results showed that the GH mRNA could be observed in the eyed eggs and even at unfertilized eggs of Siberian sturgeon. The highest amounts of GH mRNA were found at 25 and 50 dph larvae, while the lowest levels were detected at 1 and 3 dph larvae stage. These findings suggest that, the GH mRNA play a key role during developmental stages of Siberian sturgeon. PMID:27844010

Pupillary Response and Phenotype in ASD: Latency to Constriction Discriminates ASD from Typically Developing Adolescents.

PubMed

Lynch, Georgina T F; James, Stephen M; VanDam, Mark

2018-02-01

Brain imaging data describe differences in the ASD brain, including amygdala overgrowth, neural interconnectivity, and a three-phase model of neuroanatomical changes from early post-natal development through late adolescence. The pupil reflex test (PRT), a noninvasive measure of brain function, may help improve early diagnosis and elucidate underlying physiology in expression of ASD endophenotype. Commonly observed characteristics of ASD include normal visual acuity but difficulty with eye gaze and photosensitivity, suggesting deficient neuromodulation of cranial nerves. Aims of this study were to confirm sensitivity of the PRT for identifying adolescents with ASD, determine if a phenotype for a subtype of ASD marked by pupil response is present in adolescence, and determine whether differences could be observed on a neurologic exam testing cranial nerves II and III (CNII; CNIII). Using pupillometry, constriction latency was measured serving as a proxy for recording neuromodulation of cranial nerves underlying the pupillary reflex. The swinging flashlight method, used to perform the PRT for measuring constriction latency and return to baseline, discriminated ASD participants from typically developing adolescents on 72.2% of trials. Results further confirmed this measure's sensitivity within a subtype of ASD in later stages of development, serving as a correlate of neural activity within the locus-coeruleus norepinephrine (LC-NE) system. A brainstem model of atypical PRT in ASD is examined in relation to modulation of cranial nerves and atypical arousal levels subserving the atypical pupillary reflex. Autism Res 2018, 11: 364-375. © 2017 International Society for Autism Research, Wiley Periodicals, Inc. Milder forms of autism spectrum disorder (ASD) can be difficult to diagnose based on behavioral testing alone. This study used eye-tracking equipment and a hand-held penlight to measure the pupil reflex in adolescents with "high functioning" ASD and in adolescents without ASD. The ASD group showed a delay in pupil response. This is the first eye-tracking study to conduct this test as typically performed by a clinical provider, demonstrating differences in older individuals with a subtype of ASD. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Comparing multifocal VEP and standard automated perimetry in high-risk ocular hypertension and early glaucoma.

PubMed

Fortune, Brad; Demirel, Shaban; Zhang, Xian; Hood, Donald C; Patterson, Emily; Jamil, Annisa; Mansberger, Steven L; Cioffi, George A; Johnson, Chris A

2007-03-01

To compare the diagnostic performance of multifocal visual evoked potential (mfVEP) and standard automated perimetry (SAP), in eyes with high-risk ocular hypertension or early glaucoma. Both eyes of 185 individuals with high-risk ocular hypertension or early glaucoma were evaluated. Subjects ranged in age from 37 to 87 (mean +/- SD: 61 +/- 11 years). Pattern-reversal mfVEPs were obtained by using VERIS (Electro-Diagnostic Imaging, San Mateo, CA) with a four-electrode array and were analyzed with custom software. SAP visual fields (SITA-standard; Carl Zeiss Meditec, Inc., Dublin, CA) were obtained within 22.3 +/- 27.0 days of the mfVEP. Stereo disc photographs and Heidelberg Retina Tomograph (HRT) images were obtained during one visit, which was within 24.8 +/- 50.4 days of the mfVEP and 33.1 +/- 62.9 days of the SAP visual field. Abnormalities on the mfVEP were defined by using a variety of cluster criteria: SAP with pattern standard deviation (PSD) P

Glaucoma Diagnostic Ability of the Optical Coherence Tomography Angiography Vessel Density Parameters.

PubMed

Chung, Jae Keun; Hwang, Young Hoon; Wi, Jae Min; Kim, Mijin; Jung, Jong Jin

2017-11-01

To investigate the glaucoma diagnostic abilities of vessel density parameters as determined by optical coherence tomography (OCT) angiography in different stages of glaucoma. A total of 113 healthy eyes and 140 glaucomatous eyes were enrolled. Diagnostic abilities of the OCT vessel density parameters in the optic nerve head (ONH), peripapillary, and macular regions were evaluated by calculating the area under the receiver operation characteristic curves (AUCs). AUCs of the peripapillary vessel density parameters and circumpapillary retinal nerve fiber layer (RNFL) thickness were compared. OCT angiography vessel densities in the ONH, peripapillary, and macular regions in the glaucomatous eyes were significantly lower than those in the healthy eyes (P < 0.05). Among the vessel density parameters, the average peripapillary vessel density showed higher AUC than the ONH and macular region (AUCs: 0.807, 0.566, and 0.651, respectively) for glaucoma detection. The peripapillary vessel density parameters showed similar AUCs with the corresponding sectoral RNFL thickness (P > 0.05). However, in the early stage of glaucoma, the AUCs of the inferotemporal and temporal peripapillary vessel densities were significantly lower than that of the RNFL thickness (P < 0.05). The glaucomatous eyes showed decreased vessel density as determined by OCT angiography. Although the peripapillary vessel density parameters showed similar glaucoma diagnostic ability with circumpapillary RNFL thickness, in the early stage, the vessel density parameters showed limited clinical value.

Early and Late Processes in Syllogistic Reasoning: Evidence from Eye-Movements

ERIC Educational Resources Information Center

Espino, Orlando; Santamaria, Carlos; Meseguer, Enrique; Carreiras, Manuel

2005-01-01

An eye-movement monitoring experiment was carried out to examine the effects of the difficulty of the problem (simple versus complex problems) and the type of figure (figure 1 or figure 4) on the time course of processing categorical syllogisms. The results showed that the course of influence for these two factors is different. We found early…

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2010-01-28

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Metaphorical Salience in Artistic Text Processing: Evidence From Eye Movement.

PubMed

Novikova, Eleonora G; Janyan, Armina; Tsaregorodtseva, Oksana V

2015-01-01

The study aimed to explore processing difference between a literal phrase and a metaphoric one. Unlike artificially created stimuli in most experimental research, an artistic text with an ambiguous binary metaphoric phrase was used. Eye tracking methodology was applied. Results suggested difference between the two types of phrases in both early and late processing measures. © The Author(s) 2015.

Loss of the BMP Antagonist, SMOC-1, Causes Ophthalmo-Acromelic (Waardenburg Anophthalmia) Syndrome in Humans and Mice

PubMed Central

Rainger, Joe; van Beusekom, Ellen; Ramsay, Jacqueline K.; McKie, Lisa; Al-Gazali, Lihadh; Pallotta, Rosanna; Saponari, Anita; Branney, Peter; Fisher, Malcolm; Morrison, Harris; Bicknell, Louise; Gautier, Philippe; Perry, Paul; Sokhi, Kishan; Sexton, David; Bardakjian, Tanya M.; Schneider, Adele S.; Elcioglu, Nursel; Ozkinay, Ferda; Koenig, Rainer; Mégarbané, Andre; Semerci, C. Nur; Khan, Ayesha; Zafar, Saemah; Hennekam, Raoul; Sousa, Sérgio B.; Ramos, Lina; Garavelli, Livia; Furga, Andrea Superti; Wischmeijer, Anita; Jackson, Ian J.; Gillessen-Kaesbach, Gabriele; Brunner, Han G.; Wieczorek, Dagmar; van Bokhoven, Hans; FitzPatrick, David R.

2011-01-01

Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2 identified homozygous mutations in SMOC1 (SPARC-related modular calcium binding 1) in eight unrelated families. Four of these mutations are nonsense, two frame-shift, and two missense. The missense mutations are both in the second Thyroglobulin Type-1 (Tg1) domain of the protein. The orthologous gene in the mouse, Smoc1, shows site- and stage-specific expression during eye, limb, craniofacial, and somite development. We also report a targeted pre-conditional gene-trap mutation of Smoc1 (Smoc1tm1a) that reduces mRNA to ∼10% of wild-type levels. This gene-trap results in highly penetrant hindlimb post-axial oligosyndactyly in homozygous mutant animals (Smoc1tm1a/tm1a). Eye malformations, most commonly coloboma, and cleft palate occur in a significant proportion of Smoc1tm1a/tm1a embryos and pups. Thus partial loss of Smoc-1 results in a convincing phenocopy of the human disease. SMOC-1 is one of the two mammalian paralogs of Drosophila Pentagone, an inhibitor of decapentaplegic. The orthologous gene in Xenopus laevis, Smoc-1, also functions as a Bone Morphogenic Protein (BMP) antagonist in early embryogenesis. Loss of BMP antagonism during mammalian development provides a plausible explanation for both the limb and eye phenotype in humans and mice. PMID:21750680

Loss of the BMP antagonist, SMOC-1, causes Ophthalmo-acromelic (Waardenburg Anophthalmia) syndrome in humans and mice.

PubMed

Rainger, Joe; van Beusekom, Ellen; Ramsay, Jacqueline K; McKie, Lisa; Al-Gazali, Lihadh; Pallotta, Rosanna; Saponari, Anita; Branney, Peter; Fisher, Malcolm; Morrison, Harris; Bicknell, Louise; Gautier, Philippe; Perry, Paul; Sokhi, Kishan; Sexton, David; Bardakjian, Tanya M; Schneider, Adele S; Elcioglu, Nursel; Ozkinay, Ferda; Koenig, Rainer; Mégarbané, Andre; Semerci, C Nur; Khan, Ayesha; Zafar, Saemah; Hennekam, Raoul; Sousa, Sérgio B; Ramos, Lina; Garavelli, Livia; Furga, Andrea Superti; Wischmeijer, Anita; Jackson, Ian J; Gillessen-Kaesbach, Gabriele; Brunner, Han G; Wieczorek, Dagmar; van Bokhoven, Hans; Fitzpatrick, David R

2011-07-01

Ophthalmo-acromelic syndrome (OAS), also known as Waardenburg Anophthalmia syndrome, is defined by the combination of eye malformations, most commonly bilateral anophthalmia, with post-axial oligosyndactyly. Homozygosity mapping and subsequent targeted mutation analysis of a locus on 14q24.2 identified homozygous mutations in SMOC1 (SPARC-related modular calcium binding 1) in eight unrelated families. Four of these mutations are nonsense, two frame-shift, and two missense. The missense mutations are both in the second Thyroglobulin Type-1 (Tg1) domain of the protein. The orthologous gene in the mouse, Smoc1, shows site- and stage-specific expression during eye, limb, craniofacial, and somite development. We also report a targeted pre-conditional gene-trap mutation of Smoc1 (Smoc1(tm1a)) that reduces mRNA to ∼10% of wild-type levels. This gene-trap results in highly penetrant hindlimb post-axial oligosyndactyly in homozygous mutant animals (Smoc1(tm1a/tm1a)). Eye malformations, most commonly coloboma, and cleft palate occur in a significant proportion of Smoc1(tm1a/tm1a) embryos and pups. Thus partial loss of Smoc-1 results in a convincing phenocopy of the human disease. SMOC-1 is one of the two mammalian paralogs of Drosophila Pentagone, an inhibitor of decapentaplegic. The orthologous gene in Xenopus laevis, Smoc-1, also functions as a Bone Morphogenic Protein (BMP) antagonist in early embryogenesis. Loss of BMP antagonism during mammalian development provides a plausible explanation for both the limb and eye phenotype in humans and mice.

Shall we stay, or shall we switch? Continued anti-VEGF therapy versus early switch to dexamethasone implant in refractory diabetic macular edema.

PubMed

Busch, Catharina; Zur, Dinah; Fraser-Bell, Samantha; Laíns, Inês; Santos, Ana Rita; Lupidi, Marco; Cagini, Carlo; Gabrielle, Pierre-Henry; Couturier, Aude; Mané-Tauty, Valérie; Giancipoli, Ermete; Ricci, Giuseppe D'Amico; Cebeci, Zafer; Rodríguez-Valdés, Patricio J; Chaikitmongkol, Voraporn; Amphornphruet, Atchara; Hindi, Isaac; Agrawal, Kushal; Chhablani, Jay; Loewenstein, Anat; Iglicki, Matias; Rehak, Matus

2018-05-05

To compare functional and anatomical outcomes of continued anti-vascular endothelial growth factor (VEGF) therapy versus dexamethasone (DEX) implant in eyes with refractory diabetic macular edema (DME) after three initial anti-VEGF injections in a real-world setting. To be included in this retrospective multicenter, case-control study, eyes were required: (1) to present with early refractory DME, as defined by visual acuity (VA) gain ≤ 5 letters or reduction in central subfield thickness (CST) ≤ 20%, after a loading phase of anti-VEGF therapy (three monthly injections) and (2) to treat further with (a) anti-VEGF therapy or (b) DEX implant. Main outcome measures were change in visual acuity (VA) and central subfield thickness (CST) at 12 months. Due to imbalanced baseline characteristics, a matched anti-VEGF group was formed by only keeping eyes with similar baseline characteristics as those in the DEX group. A total of 110 eyes from 105 patients were included (anti-VEGF group: 72 eyes, DEX group: 38 eyes). Mean change in VA at 12 months was - 0.4 ± 10.8 letters (anti-VEGF group), and + 6.1 ± 10.6 letters (DEX group) (P = 0.004). Over the same period, mean change in CST was + 18.3 ± 145.9 µm (anti-VEGF group) and - 92.8 ± 173.6 µm (DEX group) (P < 0.001). Eyes in the DEX group were more likely to gain ≥ 10 letters (OR 3.71, 95% CI 1.19-11.61, P = 0.024) at month 12. In a real-world setting, eyes with DME considered refractory to anti-VEGF therapy after three monthly injections which were switched to DEX implant and had better visual and anatomical outcomes at 12 months than those that continued treatment with anti-VEGF therapy.

Wavefront aberrations and retinal image quality in different lenticular opacity types and densities.

PubMed

Wu, Cheng-Zhe; Jin, Hua; Shen, Zhen-Nv; Li, Ying-Jun; Cui, Xun

2017-11-10

To investigate wavefront aberrations in the entire eye and in the internal optics (lens) and retinal image qualities according to different lenticular opacity types and densities. Forty-one eyes with nuclear cataract, 33 eyes with cortical cataract, and 29 eyes with posterior subcapsular cataract were examined. In each group, wavefront aberrations in the entire eye and in the internal optics and retinal image quality were measured using a raytracing aberrometer. Eyes with cortical cataracts showed significantly higher coma-like aberrations compared to the other two groups in both entire eye and internal optic aberrations (P = 0.012 and P = 0.007, respectively). Eyes with nuclear cataract had lower spherical-like aberrations than the other two groups in both entire eye and internal optics aberrations (P < 0.001 and P < 0.001, respectively). In the nuclear cataract group, nuclear lens density was negatively correlated with internal spherical aberrations (r = -0.527, P = 0.005). Wavefront technology is useful for objective and quantitative analysis of retinal image quality deterioration in eyes with different early lenticular opacity types and densities. Understanding the wavefront optical properties of different crystalline lens opacities may help ophthalmic surgeons determine the optimal time to perform cataract surgery.

The effects of early post-hatching changes of imprinting object on the pattern of monocular/unihemispheric sleep of domestic chicks.

PubMed

Bobbo, Daniela; Vallortigara, Giorgio; Mascetti, Gian Gastone

2006-06-03

The pattern of monocular/unihemispheric sleep (Mo-Un sleep) was studied behaviourally in male and female chicks after early post-hatching changes of the imprinting object. Chicks were reared with an imprinting object on day 1 post-hatching which was removed or changed on day 2. On day 1, time spent in binocular sleep (both eyes closed) was similar in male and female chicks, though the number of episodes was lower in females than in males. There was no eye-closure bias in the pattern of Mo-Un sleep (one eye shut and the other open) in chicks of both sexes. On day 2, chicks subjected to the removal of imprinting object showed less time and number of episodes of binocular sleep than control chicks and chicks subjected to changes of imprinting object. There was no eye-closure bias in control chicks whilst a significant bias for more right Mo-Un sleep was recorded in chicks after removal and changes of imprinting object of both sexes. It is suggested that the removal or changes of imprinting object would cause a decrease of binocular sleep and trigger processes associated to secondary imprinting involving the left hemisphere. The bias for more right Mo-Un sleep (right eye-closure) could be the by-product of consolidation processes of secondary imprinting memories in the left hemisphere and/or of more left eye-opening as a result of periodical awakening of right hemisphere to control the environment after a stressful condition such as the removal or change of imprinting object.

Connective Tissue Growth Factor Is Involved in Structural Retinal Vascular Changes in Long-Term Experimental Diabetes

PubMed Central

Van Geest, Rob J.; Leeuwis, Jan Willem; Dendooven, Amélie; Pfister, Frederick; Bosch, Klazien; Hoeben, Kees A.; Vogels, Ilse M.C.; Van der Giezen, Dionne M.; Dietrich, Nadine; Hammes, Hans-Peter; Goldschmeding, Roel; Klaassen, Ingeborg; Van Noorden, Cornelis J.F.

2014-01-01

Early retinal vascular changes in the development of diabetic retinopathy (DR) include capillary basal lamina (BL) thickening, pericyte loss and the development of acellular capillaries. Expression of the CCN (connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed) family member CCN2 or connective tissue growth factor (CTGF), a potent inducer of the expression of BL components, is upregulated early in diabetes. Diabetic mice lacking one functional CTGF allele (CTGF+/−) do not show this BL thickening. As early events in DR may be interrelated, we hypothesized that CTGF plays a role in the pathological changes of retinal capillaries other than BL thickening. We studied the effects of long-term (6-8 months) streptozotocin-induced diabetes on retinal capillary BL thickness, numbers of pericytes and the development of acellular capillaries in wild type and CTGF+/− mice. Our results show that an absence of BL thickening of retinal capillaries in long-term diabetic CTGF+/− mice is associated with reduced pericyte dropout and reduced formation of acellular capillaries. We conclude that CTGF is involved in structural retinal vascular changes in diabetic rodents. Inhibition of CTGF in the eye may therefore be protective against the development of DR. PMID:24217924

Diagnosing Stroke in Acute Vertigo: The HINTS Family of Eye Movement Tests and the Future of the "Eye ECG".

PubMed

Newman-Toker, David E; Curthoys, Ian S; Halmagyi, G Michael

2015-10-01

Patients who present to the emergency department with symptoms of acute vertigo or dizziness are frequently misdiagnosed. Missed opportunities to promptly treat dangerous strokes can result in poor clinical outcomes. Inappropriate testing and incorrect treatments for those with benign peripheral vestibular disorders leads to patient harm and unnecessary costs. Over the past decade, novel bedside approaches to diagnose patients with the acute vestibular syndrome have been developed and refined. A battery of three bedside tests of ocular motor physiology known as "HINTS" (head impulse, nystagmus, test of skew) has been shown to identify acute strokes more accurately than even magnetic resonance imaging with diffusion-weighted imaging (MRI-DWI) when applied in the early acute period by eye-movement specialists. Recent advances in lightweight, high-speed video-oculography (VOG) technology have made possible a future in which HINTS might be applied by nonspecialists in frontline care settings using portable VOG. Use of technology to measure eye movements (VOG-HINTS) to diagnose stroke in the acute vestibular syndrome is analogous to the use of electrocardiography (ECG) to diagnose myocardial infarction in acute chest pain. This "eye ECG" approach could transform care for patients with acute vertigo and dizziness around the world. In the United States alone, successful implementation would likely result in improved quality of emergency care for hundreds of thousands of peripheral vestibular patients and tens of thousands of stroke patients, as well as an estimated national health care savings of roughly $1 billion per year. In this article, the authors review the origins of the HINTS approach, empiric evidence and pathophysiologic principles supporting its use, and possible uses for the eye ECG in teleconsultation, teaching, and triage. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Monocular Perceptual Deprivation from Interocular Suppression Temporarily Imbalances Ocular Dominance.

PubMed

Kim, Hyun-Woong; Kim, Chai-Youn; Blake, Randolph

2017-03-20

Early visual experience sculpts neural mechanisms that regulate the balance of influence exerted by the two eyes on cortical mechanisms underlying binocular vision [1, 2], and experience's impact on this neural balancing act continues into adulthood [3-5]. One recently described, compelling example of adult neural plasticity is the effect of patching one eye for a relatively short period of time: contrary to intuition, monocular visual deprivation actually improves the deprived eye's competitive advantage during a subsequent period of binocular rivalry [6-8], the robust form of visual competition prompted by dissimilar stimulation of the two eyes [9, 10]. Neural concomitants of this improvement in monocular dominance are reflected in measurements of brain responsiveness following eye patching [11, 12]. Here we report that patching an eye is unnecessary for producing this paradoxical deprivation effect: interocular suppression of an ordinarily visible stimulus being viewed by one eye is sufficient to produce shifts in subsequent predominance of that eye to an extent comparable to that produced by patching the eye. Moreover, this imbalance in eye dominance can also be induced by prior, extended viewing of two monocular images differing only in contrast. Regardless of how shifts in eye dominance are induced, the effect decays once the two eyes view stimuli equal in strength. These novel findings implicate the operation of interocular neural gain control that dynamically adjusts the relative balance of activity between the two eyes [13, 14]. Copyright © 2017 Elsevier Ltd. All rights reserved.

Automated classifiers for early detection and diagnosis of retinopathy in diabetic eyes.

PubMed

Somfai, Gábor Márk; Tátrai, Erika; Laurik, Lenke; Varga, Boglárka; Ölvedy, Veronika; Jiang, Hong; Wang, Jianhua; Smiddy, William E; Somogyi, Anikó; DeBuc, Delia Cabrera

2014-04-12

Artificial neural networks (ANNs) have been used to classify eye diseases, such as diabetic retinopathy (DR) and glaucoma. DR is the leading cause of blindness in working-age adults in the developed world. The implementation of DR diagnostic routines could be feasibly improved by the integration of structural and optical property test measurements of the retinal structure that provide important and complementary information for reaching a diagnosis. In this study, we evaluate the capability of several structural and optical features (thickness, total reflectance and fractal dimension) of various intraretinal layers extracted from optical coherence tomography images to train a Bayesian ANN to discriminate between healthy and diabetic eyes with and with no mild retinopathy. When exploring the probability as to whether the subject's eye was healthy (diagnostic condition, Test 1), we found that the structural and optical property features of the outer plexiform layer (OPL) and the complex formed by the ganglion cell and inner plexiform layers (GCL + IPL) provided the highest probability (positive predictive value (PPV) of 91% and 89%, respectively) for the proportion of patients with positive test results (healthy condition) who were correctly diagnosed (Test 1). The true negative, TP and PPV values remained stable despite the different sizes of training data sets (Test 2). The sensitivity, specificity and PPV were greater or close to 0.70 for the retinal nerve fiber layer's features, photoreceptor outer segments and retinal pigment epithelium when 23 diabetic eyes with mild retinopathy were mixed with 38 diabetic eyes with no retinopathy (Test 3). A Bayesian ANN trained on structural and optical features from optical coherence tomography data can successfully discriminate between healthy and diabetic eyes with and with no retinopathy. The fractal dimension of the OPL and the GCL + IPL complex predicted by the Bayesian radial basis function network provides better diagnostic utility to classify diabetic eyes with mild retinopathy. Moreover, the thickness and fractal dimension parameters of the retinal nerve fiber layer, photoreceptor outer segments and retinal pigment epithelium show promise for the diagnostic classification between diabetic eyes with and with no mild retinopathy.

The attentional blink in amblyopia.

PubMed

Popple, Ariella V; Levi, Dennis M

2008-10-31

Amblyopia is a disorder of visual acuity in one eye, thought to arise from suppression by the other eye during development of the visual cortex. In the attentional blink, the second of two targets (T2) in a Rapid Serial Visual Presentation (RSVP) stream is difficult to detect and identify when it appears shortly but not immediately after the first target (T1). We investigated the attentional blink seen through amblyopic eyes and found that it was less finely tuned in time than when the 12 amblyopic observers viewed the stimuli with their preferred eyes. T2 performance was slightly better through amblyopic eyes two frames after T1 but worse one frame after T1. Previously (A. V. Popple & D. M. Levi, 2007), we showed that when the targets were red letters in a stream of gray letters (or vice versa), normal observers frequently confused T2 with the letters before and after it (neighbor errors). Observers viewing through their amblyopic eyes made significantly fewer neighbor errors and more T2 responses consisting of letters that were never presented. In normal observers, T1 (on the rare occasions when it was reported incorrectly) was often confused with the letter immediately after it. Viewing through their amblyopic eyes, observers with amblyopia made more responses to the letter immediately before T1. These results suggest that childhood suppression of the input from amblyopic eyes disrupts attentive processing. We hypothesize reduced connectivity between monocularly tuned lower visual areas, subcortical structures that drive foveal attention, and more frontal regions of the brain responsible for letter recognition and working memory. Perhaps when viewing through their amblyopic eyes, the observers were still processing the letter identity of a prior distractor when the color flash associated with the target was detected. After T1, unfocused temporal attention may have bound together erroneously the features of succeeding letters, resulting in the appearance of letters that were not actually presented. These findings highlight the role of early (monocular) visual processes in modulating the attentional blink, as well as the role of attention in amblyopic visual deficits.

Patients with Mild Alzheimer's Disease Fail When Using Their Working Memory: Evidence from the Eye Tracking Technique.

PubMed

Fernández, Gerardo; Manes, Facundo; Politi, Luis E; Orozco, David; Schumacher, Marcela; Castro, Liliana; Agamennoni, Osvaldo; Rotstein, Nora P

2016-01-01

Patients with Alzheimer's disease (AD) develop progressive language, visuoperceptual, attentional, and oculomotor changes that can have an impact on their reading comprehension. However, few studies have examined reading behavior in AD, and none have examined the contribution of predictive cueing in reading performance. For this purpose we analyzed the eye movement behavior of 35 healthy readers (Controls) and 35 patients with probable AD during reading of regular and high-predictable sentences. The cloze predictability of words N - 1, and N + 1 exerted an influence on the reader's gaze duration. The predictabilities of preceding words in high-predictable sentences served as task-appropriate cues that were used by Control readers. In contrast, these effects were not present in AD patients. In Controls, changes in predictability significantly affected fixation duration along the sentence; noteworthy, these changes did not affect fixation durations in AD patients. Hence, only in healthy readers did predictability of upcoming words influence fixation durations via memory retrieval. Our results suggest that Controls used stored information of familiar texts for enhancing their reading performance and imply that contextual-word predictability, whose processing is proposed to require memory retrieval, only affected reading behavior in healthy subjects. In AD patients, this loss reveals impairments in brain areas such as those corresponding to working memory and memory retrieval. These findings might be relevant for expanding the options for the early detection and monitoring in the early stages of AD. Furthermore, evaluation of eye movements during reading could provide a new tool for measuring drug impact on patients' behavior.

Exposure to Atomic Bomb Radiation and Age-Related Macular Degeneration in Later Life: The Hiroshima-Nagasaki Atomic Bomb Survivor Study.

PubMed

Itakura, Katsumasa; Takahashi, Ikuno; Nakashima, Eiji; Yanagi, Masahide; Kawasaki, Ryo; Neriishi, Kazuo; Wang, Jie Jin; Wong, Tien Yin; Hida, Ayumi; Ohishi, Waka; Kiuchi, Yoshiaki

2015-08-01

To investigate the association between radiation exposure from the atomic bombings and the prevalence of age-related macular degeneration (AMD) among older residents of Hiroshima and Nagasaki. The Adult Health Study is a cohort study of atomic bomb survivors living in Hiroshima and Nagasaki, comprising 2153 participants who underwent examinations with retinal fundus photographs in 2006-2008. The radiation dose to the eye for the analysis was estimated with the revised dosimetry system (DS02). The retinal photographs were graded according to the Wisconsin Age-Related Maculopathy Grading System modified for nonstereoscopic retinal images. Early and late AMD were defined according to the type of lesion detected in the worse eye of the participants. Person-specific data were analyzed by using a logistic regression model to assess the association between radiation dose and AMD. Among the 1824 subjects with gradable retinal images (84.7% of the overall participants), the estimated eye dose was widely distributed, with a mean of 0.45 Gy and standard deviation of 0.74 Gy. The prevalence of early and late AMD was 10.5% and 0.3%, respectively. There were no significant associations between radiation dose and AMD, with each 1-Gy increase in exposure, adjusted odds ratio was 0.93 (95% confidence interval [CI], 0.75-1.15) for early AMD and 0.79 (95% CI, 0.21-2.94) for late AMD. No significant associations were found between atomic bomb irradiation early in life and the prevalence of early or late AMD later in life among Japanese atomic bomb survivors.

Glaucoma-induced optic disc morphometric changes and glaucoma diagnostic ability of Heidelberg Retina Tomograph II in highly myopic eyes.

PubMed

Mayama, Chihiro; Tsutsumi, Tae; Saito, Hitomi; Asaoka, Ryo; Tomidokoro, Atsuo; Iwase, Aiko; Otani, Shinichiro; Miyata, Kazunori; Araie, Makoto

2014-01-01

This study was performed to first investigate the morphological differences in the optic nerve head between highly myopic non-glaucomatous controls and highly myopic glaucomatous eyes in comparison with the differences between emmetropic non-glaucomatous controls and emmetropic glaucomatous eyes using confocal scanning laser ophthalmoscopy. Further, the ability of the apparatus in glaucoma diagnosis in highly myopic eyes was compared with that in emmetropic eyes. Healthy subjects and age-matched patients with early-stage open-angle glaucoma were divided into two groups: emmetropic eyes (-1.0 to +1.0 diopters) and highly myopic eyes (-12.0 to -5.0 diopters).The participants were comprised of 65 emmetropic normal eyes, 59 emmetropic glaucomatous eyes, 62 highly myopic normal eyes, and 68 highly myopic glaucomatous eyes and eyes with pathologic myopia were carefully excluded. Confocal scanning laser tomographic parameters were compared among all subjects after adjustment for age and disc area. The ROC curves and sensitivity and specificity for glaucoma detection using several clinical methods were then compared between the emmetropic and highly myopic eyes. Rim area, cup/disc area ratio, mean cup depth, and cup shape measure of glaucoma eyes are significantly different from those of normal eyes in both highly myopic eyes and emmetropic eyes. Methodological overestimation of retinal nerve fiber layer cross sectional area due to optic disc tilting was suggested in the highly myopic eyes. The diagnostic performance of glaucoma using several discriminant methods significantly deteriorated in the highly myopic eyes. In the highly myopic glaucomatous eyes, confocal scanning laser tomographic parameters were significantly different from that of non-glaucomatous highly myopic eyes but diagnostic performance of glaucoma was deteriorated than that in emmetropic eyes. These findings demonstrate the utility and limitations of the apparatus in diagnosing glaucoma in highly myopic patients.

Light intensity modulates corneal power and refraction in the chick eye exposed to continuous light.

PubMed

Cohen, Yuval; Belkin, Michael; Yehezkel, Oren; Avni, Isaac; Polat, Uri

2008-09-01

Continuous exposure of chicks to light was shown to result in severe hyperopia, accompanied by anterior segment changes, such as severe corneal flattening. Since rearing chicks in complete darkness results only in mild hyperopia and minor changes in corneal curvature, we hypothesized that light intensity may play a role in the development of refractive changes under continuous light illumination. To test this hypothesis, we examined the effects of rearing chicks under various continuous light intensities. More specifically, we investigated the refractive parameters of the chicks' eyes, and avoided light cycling effects on ocular development. To this end, thirty-eight chicks were reared under 24-h incandescent illumination, at three different light intensities: 10,000 lux (n=13), 500 lux (n=12), and 50 lux (n=13). Their eyes underwent repeated retinoscopy, keratometry, and ultrasound biometry, as well as caliper measurements of enucleated eyes. Both refraction and corneal refractive power were found to be correlated with light intensity. On day 90 after hatching, exposure to light intensities of 10,000, 500, and 50 lux resulted in hyperopia of +11.97+/-3.7 (mean+/-SD) +7.9+/-4.08 and +0.63+/-3.61 diopters (D), respectively. Under those intensities, corneal refractive power was 46.10+/-3.62, 49.72+/-4.16, and 56.88+/-4.92D, respectively. Axial length did not differ significantly among the groups. The vitreous chamber was significantly deeper in the high than in the low-intensity groups. Thus, during the early life of chicks exposed to continuous lighting, light intensity affects the vitreous chamber depth as well as the anterior segment parameters, most notably the cornea. The higher the intensity, the more severe was the corneal flattening observed and the hyperopia that developed, whereas continuous illumination at low intensities resulted in emmetropia. Thus, light intensity is an important factor that should be taken into account when studying refractive development.

Non-Invasive Health Diagnostics using Eye as a 'Window to the Body'

NASA Technical Reports Server (NTRS)

Ansari, Rafat R.

2002-01-01

As a 'window to the body', the eye offers the opportunity to use light in various forms to detect ocular and systemic abnormalities long before clinical symptoms appear and help develop preventative/therapeutic countermeasures early. The effects of space travel on human body are similar to those of normal aging. For example, radiation exposure in space could lead to formation of cataracts and cancer by damaging the DNA and causing gene mutation. Additionally, the zero-gravity environment causes fluid shifts in the upper extremities of the body and changes the way blood flows and organ system performs. Here on Earth, cataract, age-related macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma are major eye diseases and are expected to double in next two decades. To detect, prevent, and treat untoward effects of prolonged space travel in real-time requires the development of non-invasive diagnostic technologies that are compact and powerful. We are developing fiber-optic sensors to evaluate the ocular tissues in health, aging, and disease employing the techniques of dynamic light scattering (cataract, uveitis, Alzheimer's, glaucoma, DR, radiation damage, refractive surgery outcomes), auto-fluorescence (aging, DR), laser-Doppler flowmetry (choroidal blood flow), Raman spectroscopy (AMD), polarimetry (diabetes), and retinal oximetry (occult blood loss). The non-invasive feature of these technologies integrated in a head-mounted/goggles-like device permits frequent repetition of tests, enabling evaluation of the results to therapy that may ultimately be useful in various telemedicine applications on Earth and in space.

Mechanical Effects of the Surface Ectoderm on Optic Vesicle Morphogenesis in the Chick Embryo

PubMed Central

Hosseini, Hadi S.; Beebe, David C.; Taber, Larry A.

2014-01-01

Precise shaping of the eye is crucial for proper vision. Here, we use experiments on chick embryos along with computational models to examine the mechanical factors involved in the formation of the optic vesicles (OVs), which grow outward from the forebrain of the early embryo. First, mechanical dissections were used to remove the surface ectoderm (SE), a membrane that contacts the outer surfaces of the OVs. Principal components analysis of OV shapes suggests that the SE exerts asymmetric loads that cause the OVs to flatten and shear caudally during the earliest stages of eye development and later to bend in the caudal and dorsal directions. These deformations cause the initially spherical OVs to become pear-shaped. Exposure to the myosin II inhibitor blebbistatin reduced these effects, suggesting that cytoskeletal contraction controls OV shape by regulating tension in the SE. To test the physical plausibility of these interpretations, we developed 2-D finite-element models for frontal and transverse cross-sections of the forebrain, including frictionless contact between the SE and OVs. With geometric data used to specify differential growth in the OVs, these models were used to simulate each experiment (control, SE removed, no contraction). For each case, the predicted shape of the OV agrees reasonably well with experiments. The results of this study indicate that differential growth in the OV and external pressure exerted by the SE are suffcient to cause the global changes in OV shape observed during the earliest stages of eye development. PMID:25458577

Evolution of Geographic Atrophy in Participants Treated with Ranibizumab for Neovascular Age-related Macular Degeneration.

PubMed

Thavikulwat, Alisa T; Jacobs-El, Naima; Kim, Jane S; Agrón, Elvira; Hasan, Jesia; Meyerle, Catherine B; Valent, David; Cukras, Catherine A; Wiley, Henry E; Wong, Wai T; Chew, Emily Y

2017-01-01

To evaluate the risk factors, incidence, and rate of progression of geographic atrophy (GA) in eyes with neovascular age-related macular degeneration (nAMD) treated with ranibizumab. Post-hoc analysis of a prospective clinical study. 69 participants with nAMD in at least one eye. Participants were prospectively treated in the study eye with 0.5 mg intravitreal ranibizumab. Study eyes received 4 monthly injections followed by pro re nata injections until a fluid-free macula was achieved on optical coherence tomography. Risk factors assessed included baseline demographics, treatment, and ocular characteristics on imaging. Eyes were evaluated on fundus autofluorescence (FAF) for GA. The rate of GA area growth in study and fellow eyes was analyzed by linear regression of square-root transformed areas. Development of new-onset GA and rate of GA area growth measured on ocular imaging, including FAF images of the study eyes. Sixty-nine participants (mean age 78.8±7.8 years) with an average of 40.0±13.6 months of follow-up were analyzed. Twenty-two of 69 study eyes (32%) were treatment naïve. During their first year of the study, participants received an average of 9.2±3.3 injections in the study eye. Of 63 study eyes with quality baseline images, 22 (35%) had pre-existing GA. Of the remaining 41 eyes, 7 (17%) developed new-onset GA during study follow-up. Those who developed new GA were older (all ≥79 years old) and had received fewer study injections on average (6.9 vs. 10.4 injections at 1 year) compared to those who did not develop new GA. Of the 12 treatment naïve study eyes without GA at baseline, 1 (8.3%) developed new GA during the study. In 21 study eyes with quantifiable GA area, eyes with GA present at baseline (16/21) enlarged by 0.34±0.26 mm/year, compared to 0.19±0.12 mm/year in eyes developing new-onset GA (5/21). While 17% of study eyes without GA present at baseline receiving ranibizumab developed new GA, the role of ranibizumab in the development of GA is unclear. Further prospective longitudinal studies are required to determine the eyes most at risk of developing GA in the setting of anti-VEGF treatment.

Primary Eye Irritation of Guanidine Nitrate in Male Rabbits.

DTIC Science & Technology

1986-01-01

nitrate were indicated by observ;Ition of pannus (I of 6) and corneal erosions (2 of 6) that persisted through termination at day 21. i L0&.. ’- DO I FO7...animals tested showed one or more of these lesions. Potential corrosive properties of guanidine nitrate were indicated by observation of pannus (1 of 6) and...developing pannus . In four rabbits, slight (score I) iritis (vascular injection) was observed. This was noted as early as the i-hour observation and

Simulating Photo-Refraction Images of Keratoconus and Near-Sightedness Eyes

NASA Astrophysics Data System (ADS)

Baker, Kevin; Lewis, James W. L.; Chen, Ying-Ling

2004-11-01

Keratoconus is an abnormal condition of the eye resulting from cone-shaped features on the cornea that degrade the quality of vision. These corneal features result from thinning and subsequent bulging due to intraocular pressure. The abnormal corneal curvature increases the refractive power asymmetrically and can be misdiagnosed by examiners as astigmatism and nearsightedness. Since corrective treatment is possible, early detection of this condition is desirable. Photo-refraction (PR) detects the retinal irradiance reflected from a single light source and is an inexpensive method used to identify refractive errors. For near- (far-) sighted eye, a crescent appears on the same (opposite) side of the light source. The capability of a PR device to detect keratoconus and to differentiate this condition from myopia was investigated. Using a commercial optical program, synthetic eye models were constructed for both near-sighted and keratoconus eyes. PR images of various eye conditions were calculated. The keratoconus cone shapes were modeled with typical published cone locations and sizes. The results indicate significant differences between the images of keratoconus and near-sighted eyes.