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Sample records for age-matched normal eyes

  1. Evaluation of visual stress symptoms in age-matched dyslexic, Meares-Irlen syndrome and normal adults

    PubMed Central

    Alanazi, Mana A.; Alanazi, Saud A.; Osuagwu, Uchechukwu L.

    2016-01-01

    AIM To examine the prevalence of dyslexia and Meares-Irlen syndrome (MIS) among female students and determine their level of visual stress in comparison with normal subjects. METHODS A random sample of 450 female medical students of King Saud University Riyadh (age range, 18-30y) responded to a wide range of questions designed to accomplish the aims of this study. The detailed questionnaire consisted of 54 questions with 12 questions enquiring on ocular history and demography of participants while 42 questions were on visual symptoms. Items were categorized into critical and non-critical questions (CQ and NCQ) and were rated on four point Likert scale. Based on the responses obtained, the subjects were grouped into normal (control), dyslexic with or without MIS (Group 1) and subjects with MIS only (Group 2). Responses were analysed as averages and mean scores were calculated and compared between groups using one way analysis of variance to evaluate total visual stress score (TVSS=NCQ+CQ), critical and non-critical visual stress scores. The relationship between categorical variables such as age, handedness and condition were assessed with Chi-square test. RESULTS The completion rate was 97.6% and majority of the respondents (92%) were normal readers, 2% dyslexic and 6% had MIS. They were age-matched. More than half of the participants had visited an eye care practitioner in the last 2y. About 13% were recommended eye exercises and one participant experienced pattern glare. Hand preference was not associated with any condition but Group 1 subjects (3/9, 33%) were significantly more likely to be diagnosed of lazy eye than Group 2 (2/27, 7%) and control (27/414, 7%) subjects. The mean±SD of TVSS responses were 63±14 and it was 44±9 for CQ and 19±5 for NCQ. Responses from all three variables were normally distributed but the CQ responses were on the average more positive (82%) in Group 2 and less positive (46%) in Group 1 than control. With NCQ, the responses were

  2. Immunohistochemical characteristics of normal canine eyes.

    PubMed

    Labelle, P; Reilly, C M; Naydan, D K; Labelle, A L

    2012-09-01

    Immunohistochemistry is widely utilized in diagnostic laboratories to study neoplastic and nonneoplastic diseases. Knowledge of the immunohistochemical characteristics of normal tissue is essential for interpretation of immunoreactivity in pathologic conditions. In this study, immunohistochemistry was performed with a broad panel of diagnostically relevant antibodies on 4 normal canine globes--namely, vimentin, pan-cytokeratin (AE1/AE3), cytokeratin 7, cytokeratin 8/18, cytokeratin 20, α-smooth muscle actin, muscle specific actin, desmin, Melan-A, microphthalmia transcription factor, S-100, glial fibrillary acidic protein, triple neurofilaments, neuron-specific enolase, chromogranin A, synaptophysin, laminin and CD31. Results include cytokeratin immunoreactivity limited to the conjunctival epithelium, corneal epithelium, and retinal pigment epithelium; distinct patterns of immunopositivity of muscle markers; and widespread immunoreactivity for vimentin and most neural/neuroendocrine markers. These findings in normal eyes provide the basis for interpretation of ocular immunohistochemistry in dogs. Published immunophenotypes of primary ocular neoplasms are also reviewed.

  3. Better performance through amblyopic than through normal eyes.

    PubMed

    Fahle, M; Bachmann, G

    1996-07-01

    Spatio-temporal interpolation reconstructs the (complete) motion path of objects presented discontinuously, e.g. under stroboscopic illumination or in television. Interpolative vernier stimuli were created by presenting two line segments with a temporal delay instead of a spatial offset. Ten amblyopic patients had to indicate whether the lower segment of the moving target was offset to the left or right relative to the upper segment. For five patients we also measured thresholds for a conventional moving vernier. Five normal subjects were measured with sharply focused and blurred interpolative verniers. At low velocities of interpolative vernier targets, results of amblyopic eyes are inferior to those of normal eyes. However, 9 out of 10 patients perform better using their amblyopic than using their normal eye at high velocities. In control subjects, blurred stimuli yield results similar to those of amblyopic eyes, indicating a similarity between (optical) blur and the mechanisms underlying amblyopia. Thresholds for conventional vernier targets of amblyopic observers, on the other hand, are constant over the whole velocity range for both normal and amblyopic eyes, with a better performance of the normal eye at all velocities. The consequences for models of amblyopia are discussed.

  4. Eye-specific retinogeniculate segregation independent of normal neuronal activity.

    PubMed

    Huberman, Andrew D; Wang, Guo-Yong; Liets, Lauren C; Collins, Odell A; Chapman, Barbara; Chalupa, Leo M

    2003-05-09

    The segregation of initially intermingled left and right eye inputs to the dorsal lateral geniculate nucleus (DLGN) during development is thought to be in response to precise spatial and temporal patterns of spontaneous ganglion cell activity. To test this hypothesis, we disrupted the correlated activity of neighboring ganglion cells in the developing ferret retina through immunotoxin depletion of starburst amacrine cells. Despite the absence of this type of correlated activity, left and right eye inputs segregated normally in the DLGN. By contrast, when all spontaneous activity was blocked, the projections from the two eyes remained intermingled. Thus, certain features of normal neural activity patterns are not required for the formation of eye-specific projections to the DLGN.

  5. Retinal vessel density from optical coherence tomography angiography to differentiate early glaucoma, pre-perimetric glaucoma and normal eyes

    PubMed Central

    Akil, Handan; Huang, Alex S.; Francis, Brian A.; Sadda, Sirinivas R.; Chopra, Vikas

    2017-01-01

    Purpose To evaluate optic nerve vascular density using swept source optical coherence tomography angiography (OCTA) in patients with early primary open angle glaucoma (POAG), pre-perimetric glaucoma and normal eyes. Methods This is a prospective, observational study including 56 eyes in total and divided into 3 groups; 20 eyes with mild POAG, 20 pre-perimetric glaucoma eyes, and 16 age-matched normal eyes as controls. The optic disc region was imaged by a 1050-nm-wavelength swept-source OCT system (DRI OCT Triton, TOPCON). Vessel density was assessed as the ratio of the area occupied by the vessels in 3 distinct regions: 1) within the optic nerve head; 2) in the 3 mm papillary region around the optic disc; and 3) in the peripapillary region, defined as a 700-μm-wide elliptical annulus around the disc. The potential associations between vessel density and structural, functional measures were analyzed. Results There was a statistically significant difference for the peripapillary vessel density, optic nerve head vessel density, and papillary vessel density among all the groups (p<0.001). Control eyes showed a significant difference for all measured vessel densities compared to glaucomatous eyes (p values from 0.001 to 0.024). There was a statistically significant difference between control and pre-perimetric glaucoma eyes for peripapillary, optic nerve head and papillary vessel density values (p values from 0.001 to 0.007). The optic nerve head vessel density, superior and inferior papillary area vessel density (Pearson r = 0.512, 0.436, 0.523 respectively) were highly correlated with mean overall, superior and inferior RNFL thickness in POAG eyes (p = 0.04, p = 0.02 and p = 0.04 respectively). Multiple linear regression analysis of POAG group showed that optic nerve head vessel density in POAG group was more strongly linked to RNFL thickness than to any other variables. Conclusions Eyes with mild POAG could be differentiated from pre-perimetric glaucoma eyes, which

  6. Dancing Eye Syndrome associated with spontaneous recovery and normal neurodevelopment.

    PubMed

    Ki Pang, K; Lynch, Bryan J; Osborne, John P; Pike, Michael G

    2010-03-01

    Five patients with spontaneously recovering Dancing Eye Syndrome/Opsoclonus Myoclonus Syndrome are described. Age at presentation ranged from 4 to 19 months. Four had symptoms of fever and a coryzal illness within days to a few weeks prior to the onset. One of the 4 also had varicella zoster 4 weeks before presentation. All had opsoclonus, myoclonus/ataxia and irritability. Associated infective agents identified were Coxsackie virus and rotavirus. Spontaneous improvement of symptoms started within 9 days of presentation and total duration of illness ranged from 10 to 24 days. Developmental progress at follow-up was normal in all cases. A range of immunomodulatory therapies have been advocated for the treatment of Dancing Eye Syndrome/Opsoclonus Myoclonus Syndrome. However, in some children, early spontaneous recovery may occur, an observation which should be borne in mind when designing therapeutic trials in this condition.

  7. Normal SPECT thallium-201 bull's-eye display: gender differences.

    PubMed

    Eisner, R L; Tamas, M J; Cloninger, K; Shonkoff, D; Oates, J A; Gober, A M; Dunn, D W; Malko, J A; Churchwell, A L; Patterson, R E

    1988-12-01

    The bull's-eye technique synthesizes three-dimensional information from single photon emission computed tomographic 201TI images into two dimensions so that a patient's data can be compared quantitatively against a normal file. To characterize the normal database and to clarify differences between males and females, clinical data and exercise electrocardiography were used to identify 50 males and 50 females with less than 5% probability of coronary artery disease. Results show inhomogeneity of the 201TI distributions at stress and delay: septal to lateral wall count ratios are less than 1.0 in both females and males; anterior to inferior wall count ratios are greater than 1.0 in males but are approximately equal to 1.0 in females. Washout rate is faster in females than males at the same peak exercise heart rate and systolic blood pressure, despite lower exercise time. These important differences suggest that quantitative analysis of single photon emission computed tomographic 201TI images requires gender-matched normal files.

  8. Optic nerve head perfusion in normal eyes and eyes with glaucoma using optical coherence tomography-based microangiography

    PubMed Central

    Chen, Chieh-Li; Bojikian, Karine D.; Gupta, Divakar; Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Kono, Rei; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.

    2016-01-01

    Background To investigate the differences of perfusion in the optic nerve head (ONH) between normal and glaucomatous eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Methods One eye from each subject was scanned with a 68 kHz Cirrus 5000 HD-OCT-based OMAG prototype system centered at the ONH (Carl Zeiss Meditec Inc, Dublin, CA, USA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. En face OMAG images for preLC were generated using signals with highest blood flow signal intensity. ONH perfusion was quantified as flux, vessel area density, and normalized flux within the ONH. Standard t-tests were performed to analyze the ONH perfusion differences between normal and glaucomatous eyes. Linear regression models were constructed to analyze the correlation between ONH perfusion and other clinical measurements. Results Twenty normal and 21 glaucoma subjects were enrolled. Glaucomatous eyes had significantly lower ONH perfusion in preLC in all three perfusion metrics compared to normal eyes (P≤0.0003). Significant correlations between ONH perfusion and disease severity as well as structural changes were detected in glaucomatous eyes (P≤0.012). Conclusions ONH perfusion detected by OMAG showed significant differences between glaucoma and normal controls and was significantly correlated with disease severity and structural defects in glaucomatous eyes. ONH perfusion measurement using OMAG may provide useful information for detection and monitoring of glaucoma. PMID:27190764

  9. Retinal image degradation by optical aberrations and light scatter in normal and albino chick eyes

    NASA Astrophysics Data System (ADS)

    Tian, Yibin; Shieh, Kevin; Wildsoet, Christine F.

    2007-02-01

    Comprehensive evaluation of retinal image quality requires that light scatter as well as optical aberrations be considered. In investigating how retinal image degradation affects eye growth in the chick model of myopia, we developed a simple method based on Shack-Hartmann images for evaluating the effects of both monochromatic aberrations and light scatter on retinal image quality. We further evaluated our method in the current study by applying it to data collected from both normal chick eyes and albino eyes that were expected to show increased intraocular light scatter. To analyze light scatter in our method, each Shack-Hartmann dot is treated as a local point spread function (PSF) that is the convolution of a local scatter PSF and a lenslet diffraction PSF. The local scatter PSF is obtained by de-convolution, and is fitted with a circularly symmetric Gaussian function using nonlinear regressions. A whole-eye scatter PSF also can be derived from the local scatter PSFs for the analyzed pupil. Aberrations are analyzed using OSA standard Zernike polynomials, and aberration-related PSF calculated from reconstructed wavefront using fast Fourier transform. Modulation transfer functions (MTFs) are computed separately for aberration and scatter PSFs, and a whole-eye MTF is derived as the product of the two. This method was applied to 4 normal and 4 albino eyes. Compared to normal eyes, albino eyes were more aberrated and showed greater light scatter. As a result, overall retinal image degradation was much greater in albino eyes than in normal eyes, with the relative contribution to retinal image degradation of light scatter compared to aberrations also being greater for albino eyes.

  10. Eye-Hand Coordination in Children with High Functioning Autism and Asperger's Disorder Using a Gap-Overlap Paradigm

    ERIC Educational Resources Information Center

    Crippa, Alessandro; Forti, Sara; Perego, Paolo; Molteni, Massimo

    2013-01-01

    We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to…

  11. Eye and head movements in reading-disabled and normal children.

    PubMed

    Petri, J L; Anderson, M E

    1980-12-01

    Coordination of eye and head movements on nonreading tasks was investigated in 16 reading-disabled and 18 normal children aged 6 to 11 years. Types of eye movements are described and mechanisms controlling eye and head movement are reviewed. Significant differences were found between the two groups in sequencing of eye and head movements that were made in response to the appearance of visual stimuli at unexpected times and positions. Some reading-disabled children also were found to require more eye movements to achieve fixation on targets at known positions. It is suggested that the vestibular system may be implicated as a factor in the results obtained from the reading-disabled children and that the atypical eye-head movement patterns observed may did in stabilizing their visual world.

  12. Dissociated vertical deviation: an exaggerated normal eye movement used to damp cyclovertical latent nystagmus.

    PubMed Central

    Guyton, D L; Cheeseman, E W; Ellis, F J; Straumann, D; Zee, D S

    1998-01-01

    PURPOSE: Dissociated vertical deviation (DVD) has eluded explanation for more than a century. The purpose of this study has been to elucidate the etiology and mechanism of DVD. METHODS: Eye movement recordings of six young adults with DVD were made with dual-coil scleral search coils under various conditions of fixation, illumination, and head tilt. Horizontal, vertical, and torsional eye movements were recorded for both eyes simultaneously. Analyses of the simultaneous vertical and torsional movements occurring during the DVD response were used to separate and identify the component vergence and version eye movements involved. RESULTS: Typically, both horizontal and cyclovertical latent nystagmus developed upon occlusion of either eye. A cycloversion then occurred, with the fixing eye intorting and tending to depress, the covered eye extorting and elevating. Simultaneously, upward versions occurred for the maintenance of fixation, consisting variously of saccades and smooth eye movements, leading to further elevation of the eye behind the cover. The cyclovertical component of the latent nystagmus became partially damped as the DVD developed. CONCLUSIONS: In patients with an early-onset defect of binocular function, the occlusion of one eye, or even concentration on fixing with one eye, produces unbalanced input to the vestibular system. This results in latent nystagmus, sometimes seen only with magnification. The cyclovertical component of the latent nystagmus, when present, is similar to normal vestibular nystagmus induced by dynamic head tilting about an oblique axis. Such vestibular nystagmus characteristically produces a hyperdeviation of the eyes. In the case of cyclovertical latent nystagmus, the analogous hyperdeviation will persist unless corrected by a vertical vergence. A normal, oblique-muscle-mediated, cycloversion/vertical vergence is called into play. This occurs in the proper direction to correct the hyperdeviation, but it occurs in an exaggerated

  13. Central Retinal Venous Pressure in Eyes of Normal-Tension Glaucoma Patients with Optic Disc Hemorrhage

    PubMed Central

    Kim, Ko Eun; Kim, Dong Myung; Flammer, Josef; Kim, Kyoung Nam

    2015-01-01

    Objective To compare central retinal venous pressure (CRVP) among eyes with and without optic disc hemorrhage (ODH) in bilateral normal-tension glaucoma (NTG) patients and NTG eyes without an episode of ODH. Methods In this prospective study, 22 bilateral NTG patients showing a unilateral ODH and 29 bilateral NTG patients without an episode of ODH were included. Eyes were categorized into group A (n = 22, eyes with ODH), group B (n = 22, fellow eyes without ODH), and group C (n = 29, NTG eyes without an episode of ODH). A contact lens ophthalmodynamometer was used to measure CRVP and central retinal arterial pressure (CRAP). Results Intraocular pressure (IOP) measured on the day of contact lens ophthalmodynamometry showed no difference among groups. However, the mean baseline IOP in group A was significantly lower than that in group C (P = .008). The CRVP in group A (29.1 ± 10.8 mmHg) was significantly lower than that in group C (40.1 ± 8.8 mmHg, P = .001), but similar to that in group B (30.5 ± 8.7 mmHg, P = .409). A similar relationship was noted for CRAP. No significant eye-associated variable for ODH was found in group A and B by conditional logistic regression analysis (all P > 0.05). However, multivariate logistic regression analysis in groups A and C revealed that low mean baseline IOP (odds ratio [OR] = 0.69, 95% confidence interval [CI] 0.49-0.98, P = 0.043) and low CRVP (OR = 0.88, 95% CI 0.80-0.95, P = 0.003) were associated with ODH. Conclusions CRVP was lower in NTG eyes with ODH than in eyes without an episode of ODH, but similar to that of fellow eyes without ODH. These imply less likelihood of association between increased central retinal venous resistance and ODH. PMID:25996599

  14. Unilateral optic disc pit and orbital cyst in an eye with normal axial length.

    PubMed

    Dhir, Luna; Thaller, Vladimir T

    2010-01-01

    Orbital cyst and optic disc pits are both congenital embryological anomalies. Orbital cysts occurring in association with optic disc colobomata and microphthalmic eyes have been widely reported in literature. The authors describe the case of a 69-year-old man with an asymptomatic orbital mass, who was investigated and found to have a coexistent optic disc pit and orbital cyst. The axial length was normal. Visual acuity was reduced due to epiretinal membrane at the macula as a consequence of serous maculopathy secondary to the optic disc pit. No active intervention was offered due to poor visual potential, and no changes in the cyst occurred over time. This is an unusual case of coexistent orbital cyst and optic disc pit in an eye with normal axial length, although the dual pathology has previously been described in a microphthalmic eye.

  15. The anatomy at the lamina cribrosa in the normal cat eye.

    PubMed

    Radius, R L; Bade, B

    1982-10-01

    In normal cat eyes, the mean cross-sectional area of the nerve fiber bundles is greater in the temporal than in the nasal lamina cribrosa. The area occupied by the interbundle trabeculae is less in the temporal sectors than in the nasal sectors of the nerve. The number and the shape of the laminar pores are similar in all nerve sectors.

  16. Dynamic Characteristics of Saccadic Eye Movements in Normal and Mentally Retarded Children.

    ERIC Educational Resources Information Center

    Takahashi, Teruko; And Others

    1987-01-01

    Analysis of saccadic eye movements in 10 normal and 10 mentally retarded children (ages 13-15) suggested that retarded children may have difficulty in visual orientation. They followed a visual target on fewer than 50 percent of the trials, displaying frequent undershoot patterns and an average rising latency that was much longer than that of…

  17. Protein serine/threonine phosphotase-1 is essential in governing normal development of vertebrate eye.

    PubMed

    Liu, W-B; Yan, Q; Liu, F-Y; Tang, X-C; Chen, H-G; Liu, J; Nie, L; Zhang, X-W; Ji, W-K; Hu, X-H; Hu, W-F; Woodward, Z; Wu, K-L; Wu, M-X; Liu, X-L; Luo, L-X; Yu, M-B; Liu, Y-Z; Liu, S-J; Li, D W-C

    2012-12-01

    Protein serine/threonine phosphatase-1 (PP-1) is one of the key enzymes responsible for dephosphorylation in vertebrates. Protein dephosphorylation via PP-1 is implicated in many different biological processes including gene expression, cell cycle control, transformation, neuronal transmission, apoptosis, autophage and senescence. However, whether PP-1 directly controls animal development remains to be investigated. Here, we present direct evidence to show that PP-1 plays an essential role in regulating eye development of vertebrates. Using goldfish as a model system, we have shown the following novel results. First, inhibition of PP-1 activity leads to death of a majority of the treated embryos, and the survived embryos displayed severe phenotype in the eye. Second, knockdown of each catalytic subunit of PP-1 with morpholino oligomers leads to partial (PP-lα knockdown) or complete (PP-lβ or PP-lγ knockdown) death of the injected embryos. The survived embryos from PP-1α knockdown displayed clear retardation in lens differentiation. Finally, overexpression of each subunit of PP-1 also causes death of majority of the injected embryos and leads to abnormal development of goldfish eye. Mechanistically, Pax-6 is one of the major downstream targets mediating the effects of PP-1 function since the eye phenotype in Pax-6 knockdown fish is similar to that derived from overexpression of PP-1. Together, our results for the first time provide direct evidence that protein phosphatase-1 plays a key role in governing normal eye formation during goldfish development.

  18. Normal and diseased personal eye modeling using age-appropriate lens parameters

    PubMed Central

    Chen, Ying-Ling; Shi, L.; Lewis, J. W. L.; Wang, M.

    2012-01-01

    Personalized eye modeling of normal and diseased eye conditions is attractive due to the recent availability of detailed ocular measurements in clinic environments and the promise of its medical and industrial applications. In the customized modeling, the optical properties of the crystalline lens including the gradient refractive index, the lens bio-geometry and orientation are typically assigned with average lens parameters from literature since typically they are not clinically available. Although, through the optical optimization by assigning lens parameters as variables, the clinical measured wavefront aberration can be achieved, the optimized lens biometry and orientation often end up at edges of the statistical distribution. Without an effective validation of these models today, the fidelity of the final lens (and therefore the model) remains questionable. To develop a more reliable customized model without detailed lens information, we incorporate age-appropriate lens parameters as the initial condition of optical optimization. A biconic lens optimization was first performed to provide a correct lens profile for accurate lower order aberration and then followed by the wavefront optimization. Clinical subjects were selected from all ages with both normal and diseased corneal and refractive conditions. 19 ammetropic eyes ( + 4D to −11D), and 16 keratoconus eyes (mild to moderate with cylinder 0.25 to 6D) were modeled. Age- and gender-corrected refractive index was evaluated. Final models attained the lens shapes comparable to the statistical distribution in their age. PMID:22714237

  19. Nimodipine disposition and haemodynamic effects in patients with cirrhosis and age-matched controls.

    PubMed Central

    Gengo, F M; Fagan, S C; Krol, G; Bernhard, H

    1987-01-01

    Six biopsy proven cirrhotics and five age-matched controls (mean 55.3 vs 52.4 years) were randomly given single 60 mg p.o. and 30 mg s.l. doses of nimodipine. Serum concentrations and blood pressure were measured regularly over the subsequent 24 h period. The clearance of nimodipine was reduced in the patients with cirrhosis. Apparent oral clearance of nimodipine in the cirrhotic group was significantly lower than that observed in the normal group (187 +/- 163 l h-1 vs 469.6 +/- 198.4 l h-1, P less than 0.01). There were no significant changes in mean arterial pressure (MAP) in the normal subjects. There were, however, significant reductions in MAP following oral nimodipine in the cirrhotics. These reductions were significantly related to nimodipine concentrations in individual patients (P less than 0.05). PMID:3814462

  20. Sensory eye balance in surgically corrected intermittent exotropes with normal stereopsis

    PubMed Central

    Feng, Lixia; Zhou, Jiawei; Chen, Li; Hess, Robert F.

    2015-01-01

    Surgery to align a deviated or strabismic eye is often done for both functional as well as cosmetic reasons. Although amblyopia is often an impediment to regaining full binocularity in strabismics in general, intermittent exotropes, because their deviation is intermittent, have no amblyopia and some degree of stereopsis. Binocular function, including a balanced ocular dominance, could be expected to be normal after surgical correction if normal levels of stereopsis and visual acuity are postsurgically achieved. Here we used a binocular phase combination paradigm to quantitatively assess the ocular dominance in a group of surgically corrected intermittent exotropes who have normal stereo and visual acuity as defined clinically. Interestingly, we found significant interocular imbalance (balance point < 0.9) in most of the surgically treated patients (8 out 10) but in none of the controls. We conclude that the two eyes may still have a residual sensory imbalance in surgically corrected strabismus even if stereopsis is within normal limits. Our study opens the possibility that a further treatment aimed at re-balancing the ocular dominance might be necessary in surgically treated intermittent exotropia to provide more efficient binocular processing in the long term. PMID:26287935

  1. Distribution of albumin in the normal monkey eye as revealed by Evans blue fluorescence microscopy.

    PubMed

    Radius, R L; Anderson, D R

    1980-03-01

    Since intravenously injected Evans blue binds irreversibly to serum albumin, its distribution reflects albumin exchange between the intravascular and extravascular tissue compartments. In histologic specimens examined by fluorescence, microscopy, extravasated Evans blue--albumin complex was identified within the ciliary body and trabecular meshwork of normal monkey eyes. In eyes fixed by intra-arterial perfusion of fixative, no dye was identified in the choroid, retina, or optic nerve. With immersion fixation, however, some extravasation was seen in the choroid and adjacent optic nerve. In some specimens, the optic nerve was stained not only with material apparently leaking from the choroid but also from a breakdown of the blood-brain barrier in the major disc vasculature during the interval before fixative penetrates into the tissue. Perfusion fixation must be used to avoid this artifact, and freezing techniques would be even better.

  2. Comparison of macular OCTs in right and left eyes of normal people

    NASA Astrophysics Data System (ADS)

    Mahmudi, Tahereh; Kafieh, Rahele; Rabbani, Hossein; Mehri dehnavi, Alireza; Akhlagi, Mohammadreza

    2014-03-01

    Retinal 3D Optical coherence tomography (OCT) is a non-invasive imaging modality in ocular diseases. Due to large volumes of OCT data, it is better to utilize automatic extraction of information from OCT images, such as total retinal thickness and retinal nerve fiber layer thickness (RNFLT). These two thickness values have become useful indices to indicate the progress of diseases like glaucoma, according to the asymmetry between two eyes of an individual. Furthermore, the loss of ganglion cells may not be diagnosable by other tests and even not be evaluated when we only consider the thickness of one eye (due to dramatic different thickness among individuals). This can justify our need to have a comparison between thicknesses of two eyes in symmetricity. Therefore, we have proposed an asymmetry analysis of the retinal nerve layer thickness and total retinal thickness around the macula in the normal Iranian population. In the first step retinal borders are segmented by diffusion map method and thickness profiles were made. Then we found the middle point of the macula by pattern matching scheme. RNFLT and retinal thickness are analyzed in 9 sectors and the mean and standard deviation of each sector in the right and left eye are obtained. The maximums of the average RNFL thickness in right and left eyes are seen in the perifoveal nasal, and the minimums are seen in the fovea. Tolerance limits in RNFL thickness is shown to be between 0.78 to 2.4 μm for 19 volunteers used in this study.

  3. Searching for biomarkers of developmental toxicity with microarrays: normal eye morphogenesis in rodent embryos

    SciTech Connect

    Nemeth, Kimberly A.; Singh, Amar V.; Knudsen, Thomas B. . E-mail: thomas.knudsen@louisville.edu

    2005-08-07

    Gene expression arrays reveal the potential linkage of altered gene expression with specific adverse effects leading to disease phenotypes. But how closely do microarray data reflect early physiological or pharmacological measures that predict toxic event(s)? To explore this issue, we have undertaken experiments in early mouse embryos exposed to various teratogens during neurulation stages with the aim of correlating large-scale changes in gene expression across the critical period during exposure. This study reports some of the large-scale changes in gene expression that can be detected in the optic rudiment of the developing mouse and rat embryo across the window of development during which the eye is exceedingly sensitive to teratogen-induced micro-/anophthalmia. Microarray analysis was performed on RNA from the headfold or ocular region at the optic vesicle and optic cup stages when the ocular primordium is enriched for Pax-6, a master control gene for eye morphogenesis. Statistical selection of differentially regulated genes and various clustering techniques identified groups of genes in upward or downward trajectories in the normal optic primordium during early eye development in mouse and rat species. We identified 165 genes with significant differential expression during eye development, and a smaller subset of 58 genes that showed a tight correlation between mouse-rat development. Significantly over-represented functional categories included fatty acid metabolism (up-regulated) and glycolysis (down-regulated). From studies such as these that benchmark large-scale gene expression during normal embryonic development, we may be able to identify the panel of biomarkers that best correlate with species differences and the risks for developmental toxicity.

  4. Immunolocalization of CYP1B1 in normal, human, fetal and adult eyes.

    PubMed

    Doshi, Manali; Marcus, Craig; Bejjani, Bassem A; Edward, Deepak P

    2006-01-01

    CYP1B1 is a cytochrome P450 enzyme implicated in autosomal recessive primary congenital glaucoma (PCG). The mechanism and function of CYP1B1 in the development of the PCG phenotype is unknown. Previously, investigators have reported detection of Cyp1b1 mRNA in the ciliary body and epithelium and neuroepithelium in the developing mouse eye, employing in situ hybridization techniques. Similarly, additional investigators have detected CYP1B1 mRNA in the iris, ciliary body, non-pigmented ciliary epithelial line, cornea, retinal-pigment epithelium, and retina in the human adult eye, using Northern blotting. This study was designed to immunolocalize CYP1B1 protein in the various ocular structures of normal, human fetal and adult eyes. Normal fetal and adult eyes were immunolabeled with a polyclonal antibody against human CYP1B1 using indirect immunofluorescence, and then compared with appropriate controls. The intensity of immunolabeling of the various ocular structures was assessed by qualitative and semi-quantitative techniques. In the anterior segment anti-CYP1B1 immunoreactivity (IR) was detected early in fetal development in the primitive ciliary epithelium. As well, the most intense CYP1B1 IR was in the non-pigmented ciliary epithelium. In addition, CYP1B1 IR was also present in the corneal epithelium and keratocytes, both layers of the iris pigmented epithelium, and retina. However, CYP1B1 IR was absent in the trabecular meshwork in all of the samples. In general, CYP1B1 immunolabeling in the human fetal eyes was more intense when compared to adult eyes. CYP1B1 IR was primarily immunolocalized to the non-pigmented ciliary epithelium and early in fetal development. In addition, CYP1B1 IR was not detected in the trabecular meshwork. These findings suggest that the abnormalities in the development of the trabecular meshwork in PCG may result from diminished or absent metabolism of important endogenous substrates in the ciliary epithelium due to non-functional CYP1B1

  5. Analysis of normal human eye with different age groups using infrared images.

    PubMed

    Acharya, U Rajendra; Ng, E Y K; Yee, Gerk Chang; Hua, Tan Jian; Kagathi, Manjunath

    2009-06-01

    The human body temperature is a good health indicator. All objects emit thermal radiation as a function temperature and wavelength for all wavelengths. The wavelength of infrared rays lies between visible and microwave radiations ranging between 700 nm to 0.1 mm. Infrared (IR) imaging is relatively inexpensive, noninvasive and harmless. Nowadays, it is widely used in the medical field for diagnosis. In this work, we have applied image processing techniques on the IR images of the eye for the analysis of the ocular surface temperature (OST) of the normal subjects of three categories (young, middle and old ages). In our study, 67 IR normal images were analyzed. Two parameters, average ocular temperature and the temperature deviation were proposed to study the variability of OST in different normal category subjects. Our study shows that, the two parameters proposed, show distinct ranges for different groups with 'p' values less than 0.05.

  6. Lamina Cribrosa Microarchitecture in Normal Monkey Eyes Part 1: Methods and Initial Results

    PubMed Central

    Lockwood, Howard; Reynaud, Juan; Gardiner, Stuart; Grimm, Jonathan; Libertiaux, Vincent; Downs, J. Crawford; Yang, Hongli; Burgoyne, Claude F.

    2015-01-01

    Purpose. To introduce quantitative postmortem lamina cribrosa (LC) microarchitecture (LMA) assessment and characterize beam diameter (BD), pore diameter (PD), and connective tissue volume fraction (CTVF) in 21 normal monkey eyes. Methods. Optic nerve heads (ONHs) underwent digital three-dimensional (3D) 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 one of twelve 30° sectors in a common cylinder. Mean BD, PD, and CTVF within 12 central and 12 peripheral subsectors and within inner, middle, and outer LC depths were assessed for sector, subsector, and depth effects by analysis of variance using general estimating equations. Eye-specific LMA discordance (the pattern of lowest connective tissue density) was plotted for each parameter. Results. The ranges of mean BD, PD, and CTVF were 14.0 to 23.1 μm, 20.0 to 35.6 μm, and 0.247 to 0.638, respectively. Sector, subsector, and depth effects were significant (P < 0.01) for all parameters except subsector on CTVF. Beam diameter and CTVF were smaller and PD was larger within the superior-temporal (ST) and inferior-temporal (IT) sectors (P < 0.05). These differences were enhanced within the central versus peripheral subsectors. Beam diameter and CTVF were larger and PD was smaller (P < 0.05) within the middle LC layer. Lamina cribrosa microarchitecture discordance most commonly occurred within the ST and IT sectors, varied by eye, and generally diminished as CTVF increased. Conclusions. Our data support previous characterizations of diminished connective tissue density within the ST and IT ONH regions. The clinical importance of eye-specific LMA discordance warrants further study. PMID:25650423

  7. Effects of Exercise on the Structure and Circulation of Choroid in Normal Eyes

    PubMed Central

    Mori, Junya; Okuda, Natsuki; Imaizumi, Hiroko; Iwasaki, Masanori; Shimizu, Miho; Miyamoto, Hirotomo; Akaiwa, Kei; Semba, Kentaro; Sonoda, Shozo; Sakamoto, Taiji; Mitamura, Yoshinori

    2016-01-01

    Aims To determine the effects of dynamic exercise on the circulation and the luminal and stromal areas of the choroid in normal eyes. Methods This was a prospective interventional study of 38 eyes of 38 normal subjects enrolled by invitation. The systolic and diastolic blood pressures, heart rate, intraocularpressure, mean ocular perfusion pressure (MOPP), choroidal blood velocity, and enhanced depth imaging optical coherence tomographic (EDI-OCT) images were recorded before, and immediately after mild dynamic exercise. The same measurements were recorded after 10 min of rest. The choroidal blood velocity was measured bylaser speckle flowgraphy, and the mean blur rate was used for the evaluations. The horizontal EDI-OCT images of the subfoveal choroid were converted to binary images. The central choroidal thickness (CCT), total cross sectional choroidal area, luminal areas, stromal areas, and the ratio of luminal area to total choroidal area (L/C ratio) were determined from these images. Results The systolic and diastolic blood pressures, heart rate, MOPP, and the mean blur rate were significantly increased immediately after the exercise and significantly decreased 10 minutes after the exercise. There wereno significant changes in the mean CCT, the mean total choroidal area, the mean luminal and stromal areas, and the mean L/C ratio after the exercise. Conclusions Our results suggest that a rest period is needed before measurements of blood flow velocity but not necessary for the EDI-OCT imaging to determine the choroidal thickness and area. PMID:27973598

  8. Fellow Eye in Unilateral Primary Congenital Glaucoma

    PubMed Central

    2017-01-01

    ABSTRACT Aim This is a report of the incidence of bilateral cases in a cohort of primary congenital glaucoma (PCG) cases and a study of the biometric characteristics of the fellow normal eyes in unilateral cases. Materials and methods The charts of 134 PCG children were reviewed, of which 78 cases (58.2%) were found to have bilateral disease. The remaining 56 patients (41.8%) with unilateral disease had their fellow normal eyes compared with an age-matched cohort of ophthalmologically free children. Results There were no differences between the normal fellow eyes of PCG cases and the control eyes in the corneal diameter and central corneal thickness (CCT), whereas the normal fellow eyes of PCG cases had higher intraocular pressure (IOP) and cup/disc (C/D) ratios. Conclusion The fellow eyes of apparently unilateral PCG cases are not typically normal anatomically like other children unaffected by PCG. Clinical significance A very high index of suspicion has to be kept for PCG cases that present apparently unilaterally, and meticulous prolonged follow-up is mandatory. How to cite this article Bayoumi NHL. Fellow Eye in Unilateral Primary Congenital Glaucoma. J Curr Glaucoma Pract 2017;11(1):28-30. PMID:28138215

  9. Anterior segment angiography of the normal canine eye: a comparison between indocyanine green and sodium fluorescein.

    PubMed

    Pirie, C G; Alario, A

    2014-03-01

    The objective of this study was to assess and compare indocyanine green (IG) and sodium fluorescein (SF) angiographic findings in the normal canine anterior segment using a digital single lens reflex (dSLR) camera adaptor. Images were obtained from 10 brown-eyed Beagles, free of ocular and systemic disease. All animals received butorphanol (0.2 mg/kg IM), maropitant citrate (1.0 mg/kg SC) and diphenhydramine (2.0 mg/kg SC) 20 min prior to propofol (4 mg/kg IV bolus, 0.2 mg/kg/min continuous rate infusion). Standard color imaging was performed prior to the administration of 0.25% IG (1 mg/kg IV). Imaging was performed using a full spectrum dSLR camera, dSLR camera adaptor, camera lens (Canon 60 mm f/2.8 Macro) and an accessory flash. Images were obtained at a rate of 1/s immediately following IG bolus for 30 s, then at 1, 2, 3, 4 and 5 min. Ten minutes later, 10% SF (20 mg/kg IV) was administered. Imaging was repeated using the same adaptor system and imaging sequence protocol. Arterial, capillary and venous phases were identified during anterior segment IG angiography (ASIGA) and their time sequences were recorded. ASIGA offered improved visualization of the iris vasculature in heavily pigmented eyes compared to anterior segment SF angiography (ASSFA), since visualization of the vascular pattern during ASSFA was not possible due to pigment masking. Leakage of SF was noted in a total of six eyes. The use of IG and SF was not associated with any observed adverse events. The adaptor described here provides a cost-effective alternative to existing imaging systems.

  10. Macular thickness and macular volume measurements using spectral domain optical coherence tomography in normal Nepalese eyes

    PubMed Central

    Pokharel, Amrit; Shrestha, Gauri Shankar; Shrestha, Jyoti Baba

    2016-01-01

    Purpose To record the normative values for macular thickness and macular volume in normal Nepalese eyes. Methods In all, 126 eyes of 63 emmetropic subjects (mean age: 21.17±6.76 years; range: 10–37 years) were assessed for macular thickness and macular volume, using spectral domain-optical coherence tomography over 6×6 mm2 in the posterior pole. A fast macular thickness protocol was employed. Statistics such as the mean, median, standard deviation, percentiles, and range were used, while a P-value was set at 0.05 to test significance. Results Average macular thickness and total macular volume were larger in males compared to females. With each year of increasing age, these variables decreased by 0.556 μm and 0.0156 mm3 for average macular thickness and total macular volume, respectively. The macular thickness was greatest in the inner superior section and lowest at the center of the fovea. The volume was greatest in the outer nasal section and thinnest in the fovea. The central subfield thickness (r=−0.243, P=0.055) and foveal volume (r=0.216, P=0.09) did not correlate with age. Conclusion Males and females differ significantly with regard to macular thickness and macular volume measurements. Reports by other studies that the increase in axial length reduced thickness and volume, were negated by this study which found a positive correlation among axial length, thickness, and volume. PMID:27041990

  11. Optic Disc Perfusion in Primary Open Angle and Normal Tension Glaucoma Eyes Using Optical Coherence Tomography-Based Microangiography

    PubMed Central

    Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Gupta, Divakar; Mudumbai, Raghu C.; Johnstone, Murray A.; Wang, Ruikang K.; Chen, Philip P.

    2016-01-01

    Purpose To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Design Cross-sectional, observational study. Subjects Twenty-eight normal, 30 POAG, and 31 NTG subjects. Methods One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. Main Outcome Measures Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH. Results Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes. Conclusions Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for

  12. Argon laser trabeculoplasty as a means of decreasing intraocular pressure from ''normal'' levels in glaucomatous eyes

    SciTech Connect

    Sharpe, E.D.; Simmons, R.J.

    1985-06-15

    The authors conducted a retrospective study of 67 patients (85 eyes) with severe glaucoma to determine whether argon laser trabeculoplasty could reduce intraocular pressures below the ''normal'' range. All patients had initial intraocular pressures of less than or equal to 19 mm Hg. Success was defined as a decrease in intraocular pressure of at least 20%, no increase in medications, stable visual field, and no subsequent glaucoma surgery. After an average follow-up period of 30 months, treatment was successful in 31 cases. One half of the failures occurred by six months and 11 failures (30%) occurred after 12 months. Sixteen patients were able to decrease their medications. Two patients achieved intraocular pressures between 6 and 9 mm Hg and 20 between 10 and 12 mm Hg.

  13. Effect of age and sex on retinal layer thickness and volume in normal eyes

    PubMed Central

    Won, Jae Yon; Kim, Sung Eun; Park, Young-Hoon

    2016-01-01

    Abstract The aim of the study was to evaluate the effect of sex and age on the thickness of the retinal layer in normal eyes using spectral-domain optical coherence tomography (SD-OCT). Fifty healthy subjects between the ages of 20 and 80 had their retinal layers measured using SD-OCT at Seoul St. Mary's Hospital. Mean thickness and volume were measured for 9 retinal layers in the fovea, the pericentral ring, and the peripheral ring. The differences of sex- and age-related thickness and volume in each retinal layer were analyzed. The retinal nerve fiber layer (RNFL), ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer (INL), and outer plexiform layer (OPL) were thinnest in the fovea area, whereas the outer nuclear layer (ONL), photoreceptor layer (PHL), and retinal pigment epithelium (RPE) were thickest at similar locations. Mean thickness of the RNFL, GCL, IPL, and OPL was significantly greater in men than women. However, mean thickness of the ONL was greater in women than in men. When compared between patients < 30 years and > 60 years of age, the thickness and volume of peripheral RNFL, GCL, and pericentral and peripheral IPL were significantly larger in the younger group than the older group. Conversely, the thickness and volume of foveal INL and IR were larger in the older group than in the younger group. The thickness and volume of the retinal layer in normal eyes significantly vary depending on age and sex. These results should be considered when evaluating layer analysis in retinal disease. PMID:27861391

  14. Diurnal variations in luminal and stromal areas of choroid in normal eyes

    PubMed Central

    Kinoshita, Takamasa; Mitamura, Yoshinori; Shinomiya, Kayo; Egawa, Mariko; Iwata, Akiko; Fujihara, Akiko; Ogushi, Yoko; Semba, Kentaro; Akaiwa, Kei; Uchino, Eisuke; Sonoda, Shozo; Sakamoto, Taiji

    2017-01-01

    Aims To determine the diurnal variations of the luminal and stromal areas of the choroid in normal eyes. Methods This was a prospective observational study of 38 eyes of 38 normal subjects. The blood pressure, heart rate, intraocular pressure and enhanced depth imaging optical coherence tomographic (EDI-OCT) images were recorded every 3 hours between 6:00 and 21:00 hours. The horizontal EDI-OCT images of the subfoveal choroid were converted to binary images. The central choroidal thickness (CCT), total cross-sectional choroidal area, the luminal areas, stromal areas and the ratio of luminal area to total choroidal area (L/C ratio) were determined. Results There were significant diurnal variations in the CCT, total choroidal area, luminal area and L/C ratio with the maximum values at 6:00 hours and the minimum values at 15:00 hours (p<0.001 for the CCT, p=0.011 for the total choroidal area, p<0.001 for the luminal area and p=0.014 for the L/C ratio). There was no significant variation in the stromal area (p=0.216). The range of fluctuation in the CCT was significantly correlated with that in the luminal area and the total choroidal area (p<0.001). However, there was no significant correlation between the fluctuation range in the CCT and that in the stromal area (p=0.095). There was no statistical relationship between the systemic parameters and the choroidal parameters. Conclusions The changes in the luminal area are most likely responsible for the diurnal change in the CCT and subfoveal choroidal area. Trial registration number UMIN000019060, Pre-results. PMID:27297216

  15. Variation of Laminar Depth in Normal Eyes With Age and Race

    PubMed Central

    Rhodes, Lindsay A.; Huisingh, Carrie; Johnstone, John; Fazio, Massimo; Smith, Brandon; Clark, Mark; Downs, J. Crawford; Owsley, Cynthia; Girard, Michael J. A.; Mari, Jean Martial; Girkin, Christopher

    2014-01-01

    Purpose. To determine if laminar depth (LD) and prelaminar tissue volume (PTV) are associated with age and race in healthy human eyes. Methods. Optic nerve head images from enhanced depth imaging spectral-domain optical coherence tomography of 166 normal eyes from 84 subjects of African descent (AD) and European descent (ED) were manually delineated to identify the principal surfaces: internal limiting membrane, Bruch's membrane (BM), anterior sclera (AS), and anterior surface of the lamina cribrosa. These four surfaces defined the LD and PTV using Bruch's membrane opening (BMO) and AS for reference structures. Generalized estimating equations were used to evaluate whether the effect of age on each outcome was differential by race. Results. When age was analyzed as a continuous variable, the interaction term between age and race was statistically significant for mean LDBMO (P = 0.015) and mean LDAS (P = 0.0062) after adjusting for axial length and BMO area. For every 1-year increase in age, the LDAS was greater on average by 1.78 μm in AD subjects and less by 1.71 μm in ED subjects. Mean PTV was lower in the older subjects (1248 × 106 μm3 AD, 881 × 106 μm3 ED) compared to the younger subjects (1316 × 106 μm3 AD, 1102 × 106 μm3 ED) in both groups. Conclusions. With increasing age, the LD changes differently across racial groups in normal subjects. The LD in ED subjects showed a significantly decreasing slope suggesting that the lamina moves anteriorly with age in this group. PMID:25414182

  16. Peripapillary Choroidal Thickness Variation With Age and Race in Normal Eyes

    PubMed Central

    Rhodes, Lindsay A.; Huisingh, Carrie; Johnstone, John; Fazio, Massimo A.; Smith, Brandon; Wang, Lan; Clark, Mark; Downs, J. Crawford; Owsley, Cynthia; Girard, Michael J. A.; Mari, Jean Martial; Girkin, Christopher A.

    2015-01-01

    Purpose. This study examined the association between peripapillary choroidal thickness (PCT) with age and race in a group of African descent (AD) and European descent (ED) subjects with normal eyes. Methods. Optic nerve head images from enhanced depth imaging spectral-domain optical coherence tomography of 166 normal eyes from 84 subjects of AD and ED were manually delineated to identify the principal surfaces of Bruch's membrane (BM), Bruch's membrane opening (BMO), and anterior sclera (AS). Peripapillary choroidal thickness was measured between BM and AS at increasing distance away from BMO. The mean PCT was compared between AD and ED subjects and generalized estimating equation (GEE) regression analysis was used to examine the association between race and PCT overall, in each quadrant, and by distance from BMO. Models were adjusted for age, BMO area, and axial length in the regression analysis. Results. Overall, the mean PCT increased from 63.9 μm ± 18.1 at 0 to 250 μm to 170.3 μm ± 56.7 at 1500 to 2000 μm from BMO. Individuals of AD had a greater mean PCT than those of ED at all distances from BMO (P < 0.05 at each distance) and in each quadrant (P < 0.05 in each quadrant). Results from multivariate regression indicate that ED subjects had significantly lower PCT compared to AD overall and in all quadrants and distances from BMO. Increasing age was also significantly associated with a lower PCT in both ED and AD participants. Conclusions. Peripapillary choroidal thickness varies with race and age, as individuals of AD have a thicker peripapillary choroid than those of ED. (ClinicalTrials.gov number, NCT00221923.) PMID:25711640

  17. Gaze position corrective eye movements in normal subjects and in patients with vestibular deficits.

    PubMed

    Peng, Grace C Y; Minor, Lloyd B; Zee, David S

    2005-04-01

    Eye movements in response to high-acceleration head rotations (thrusts) in the horizontal plane from patients with unilateral (UVD) or bilateral vestibular loss (BVD) were recorded. The rapid, gaze-position corrections (GPCs) that appeared when vestibulo-ocular reflex (VOR) slow phases were undercompensatory were characterized. For comparison, eye movements from normal subjects who were asked to generate saccades in the direction opposite head rotation (in the same direction as slow phases) were recorded. This normal-subject model produced responses with spatial and temporal characteristics similar to those from GPCs in patients as follows: When head rotations were generated actively, compared with passively, gaze-position errors and corresponding GPCs were smaller and occurred earlier. During passively generated head thrusts, GPCs still occurred when head rotations were made in total darkness, though their accuracy decreased as the requirement for maintaining gaze on a specific location in space was relaxed. Time of onset of GPCs was not rigidly tied to head kinematics (peak velocity or peak acceleration). Speeds of GPCs, however, were lower than speeds of similar-sized, head-fixed saccades. Finally, during passive and active head thrusts in patients, sustained, high-frequency (20 to 30 Hz) oscillations that appeared as tiny saccades were occasionally observed, one immediately following the other, resembling a compensatory slow-phase response. Taken together, the results suggest that one strategy for overcoming a VOR deficit is to enlist the saccadic system to produce an oculomotor response that is required to compensate for head rotation. This response may come in the form of high-velocity GPCs or smaller-amplitude oscillations.

  18. Discrimination between normal and glaucomatous eyes with visual field and scanning laser polarimetry measurements

    PubMed Central

    Lauande-Pimentel, R.; Carvalho, R.; Oliveira, H.; Goncalves, D.; Silva, L.; Costa, V.

    2001-01-01

    AIM—To evaluate the ability of structural parameters (as determined by retinal nerve fibre layer (RNFL) measurements obtained with the scanning laser polarimeter (SLP-NFA/GDx)) and functional parameters (as determined by automated perimetry) to discriminate between normal and glaucomatous eyes.
METHODS—In a case-control study, a total of 91 normal subjects and 94 patients with glaucoma underwent automated perimetry and RNFL measurements obtained with the SLP. Three independent scans of each eye were obtained and a mean image was created and used for further analysis. Only one eye per individual was randomly included in the study. The sensitivity (Se) and specificity (Sp) of 12 RNFL parameters were calculated according to the SLP internal normative database. The Se and Sp of the visual field (VF) global indices and the glaucoma hemifield test (GHT) were also calculated according to the instrument's normative database. Receiver operator characteristic (ROC) curves were built for each SLP parameter and VF index. Fisher's linear discriminant formulas (LDFs) were developed for VF indices (VF LDF), SLP measurements (SLP LDF), and both examinations (combined LDF).
RESULTS—According to the SLP internal database, the parameters with better Se and Sp were: superior/nasal ratio (Se = 58.5%; Sp = 86.8%), and GDx the number (Se = 43.3%; Sp = 96.7%). The construction of an ROC curve for the number resulted in Se = 84% and Sp = 79%. The creation of LDFs improved both the sensitivities and specificities when compared with isolated parameters SLP LDF (Se = 90.4%; Sp = 82.4%), VF LDF (Se = 89.4%; Sp = 89.0%), and combined LDF (Se = 93.0%; Sp = 90.1%). The sensitivity to diagnose early and moderate glaucomatous damage observed with the GHT was lower than that obtained with the number (p<0.01).
CONCLUSIONS—Creation of LDFs enhanced the Se and Sp for both VF and SLP. Integration of SLP and VF in a combined LDF reached the highest Se/Sp relation

  19. Optical Coherence Tomography Measurement of Macular and Nerve Fiber Layer Thickness in Normal and Glaucomatous Human Eyes

    PubMed Central

    Guedes, Viviane; Schuman, Joel S.; Hertzmark, Ellen; Wollstein, Gadi; Correnti, Anthony; Mancini, Ronald; Lederer, David; Voskanian, Serineh; Velazquez, Leonardo; Pakter, Helena M.; Pedut-Kloizman, Tamar; Fujimoto, James G.; Mattox, Cynthia

    2007-01-01

    Purpose To evaluate the hypothesis that macular thickness correlates with the diagnosis of glaucoma. Design Cross-sectional study. Participants We studied 367 subjects (534 eyes), including 166 eyes of 109 normal subjects, 83 eyes of 58 glaucoma suspects, 196 eyes of 132 early glaucoma patients, and 89 eyes of 68 advanced glaucoma patients. Methods We used optical coherence tomography (OCT) to measure macular and nerve fiber layer (NFL) thickness and to analyze their correlation with each other and with glaucoma status. We used both the commercial and prototype OCT units and evaluated correspondence between measurements performed on the same eyes on the same days. Main Outcome Measure Macular and NFL thickness as measured by OCT. Results All NFL parameters both in prototype and commercial OCT units were statistically significantly different comparing normal subjects and either early or advanced glaucoma (P < 0.001). Inner ring, outer ring, and mean macular thickness both in prototype and commercial OCT devices were found to be significantly different between normal subjects and advanced glaucomatous eyes (P < 0.001). The outer ring was the only macular parameter that could significantly differentiate between normal and early glaucoma with either the prototype or commercial OCT unit (P = 0.003, P = 0.008, respectively). The area under the receiver operator characteristic (AROC) curves comparing mean NFL thickness between normal and advanced glaucomatous eyes was 1.00 for both the prototype and commercial OCT devices for eyes scanned on both machines on the same day. The AROC comparing mean macular thickness in normal and advanced glaucomatous eyes scanned on both machines on the same day was 0.88 for the prototype OCT device and 0.80 for the commercial OCT. Conclusions Both macular and NFL thickness as measured by OCT showed statistically significant correlations with glaucoma, although NFL thickness showed a stronger association than macular thickness. There was

  20. Characterization of Choroidal Layers in Normal Aging Eyes Using Enface Swept-Source Optical Coherence Tomography

    PubMed Central

    Mullins, Robert F.; Baumal, Caroline R.; Mohler, Kathrin J.; Kraus, Martin F.; Liu, Jonathan; Badaro, Emmerson; Alasil, Tarek; Hornegger, Joachim; Fujimoto, James G.; Duker, Jay S.; Waheed, Nadia K.

    2015-01-01

    Purpose To characterize qualitative and quantitative features of the choroid in normal eyes using enface swept-source optical coherence tomography (SS-OCT). Methods Fifty-two eyes of 26 consecutive normal subjects were prospectively recruited to obtain multiple three-dimensional 12x12mm volumetric scans using a long-wavelength high-speed SS-OCT prototype. A motion-correction algorithm merged multiple SS-OCT volumes to improve signal. Retinal pigment epithelium (RPE) was segmented as the reference and enface images were extracted at varying depths every 4.13μm intervals. Systematic analysis of the choroid at different depths was performed to qualitatively assess the morphology of the choroid and quantify the absolute thicknesses as well as the relative thicknesses of the choroidal vascular layers including the choroidal microvasculature (choriocapillaris, terminal arterioles and venules; CC) and choroidal vessels (CV) with respect to the subfoveal total choroidal thickness (TC). Subjects were divided into two age groups: younger (<40 years) and older (≥40 years). Results Mean age of subjects was 41.92 (24-66) years. Enface images at the level of the RPE, CC, CV, and choroidal-scleral interface were used to assess specific qualitative features. In the younger age group, the mean absolute thicknesses were: TC 379.4μm (SD±75.7μm), CC 81.3μm (SD±21.2μm) and CV 298.1μm (SD±63.7μm). In the older group, the mean absolute thicknesses were: TC 305.0μm (SD±50.9μm), CC 56.4μm (SD±12.1μm) and CV 248.6μm (SD±49.7μm). In the younger group, the relative thicknesses of the individual choroidal layers were: CC 21.5% (SD±4.0%) and CV 78.4% (SD±4.0%). In the older group, the relative thicknesses were: CC 18.9% (SD±4.5%) and CV 81.1% (SD±4.5%). The absolute thicknesses were smaller in the older age group for all choroidal layers (TC p=0.006, CC p=0.0003, CV p=0.03) while the relative thickness was smaller only for the CC (p=0.04). Conclusions Enface SS-OCT at

  1. Pulsatile flow into the aqueous veins: Manifestations in normal and glaucomatous eyes

    PubMed Central

    Johnstone, Murray; Martin, Elizabeth; Jamil, Annisa

    2015-01-01

    The aqueous outflow system is unique because nowhere else can the pattern of flow of an extravascular fluid be directly observed as it returns to the vascular system. Such observations reveal that aqueous flow both from Schlemm’s canal into the aqueous veins and from the aqueous veins into the episcleral veins is pulsatile. Pulsatile aqueous flow mechanisms are observable in vivo not only in normal and but also in glaucomatous eyes. A series of specific patterns accompany the pulsatile mixing of aqueous with blood in the episcleral veins. These directly observable patterns of pulsatile flow are synchronous with intraocular pressure (IOP) transients induced by the cardiac pulse, blinking and eye movement. Patterns of pulsatile flow are altered by events that increase IOP such as pressure on the side of the eye, tonography and water drinking. Pulsatile flow stops when IOP is reduced below its resting level, but begins again when IOP returns to the resting level. Pulsatile flow reduction probably results from the intrinsic reduction of pulse amplitude at a lower IOP, and may thus provide a passive mechanism to maintain short-term homeostasis. Thus modulation of the pulsatile flow phenomenon appears to maintain a homeostatic IOP setpoint. Visible pulsatile flow abnormalities develop in glaucoma patients. Medications that reduce IOP through improvement in outflow do so through pulsatile flow mechanisms. Laboratory studies have demonstrated that cyclic stresses in outflow tissues alter signaling pathways, cytoskeletal responses, extracellular matrix composition and cytokine secretion. How physiologic pulse transients orchestrate cellular responses and how cellular responses identified in the laboratory may in turn regulate pulsatile aqueous outflow is unknown. Linkage of laboratory and in vivo observations await an improved understanding of how cellular and extracellular structures within the outflow system are able to generate an aqueous pulse wave. The purpose of the

  2. 3D modeling to characterize lamina cribrosa surface and pore geometries using in vivo images from normal and glaucomatous eyes.

    PubMed

    Sredar, Nripun; Ivers, Kevin M; Queener, Hope M; Zouridakis, George; Porter, Jason

    2013-07-01

    En face adaptive optics scanning laser ophthalmoscope (AOSLO) images of the anterior lamina cribrosa surface (ALCS) represent a 2D projected view of a 3D laminar surface. Using spectral domain optical coherence tomography images acquired in living monkey eyes, a thin plate spline was used to model the ALCS in 3D. The 2D AOSLO images were registered and projected onto the 3D surface that was then tessellated into a triangular mesh to characterize differences in pore geometry between 2D and 3D images. Following 3D transformation of the anterior laminar surface in 11 normal eyes, mean pore area increased by 5.1 ± 2.0% with a minimal change in pore elongation (mean change = 0.0 ± 0.2%). These small changes were due to the relatively flat laminar surfaces inherent in normal eyes (mean radius of curvature = 3.0 ± 0.5 mm). The mean increase in pore area was larger following 3D transformation in 4 glaucomatous eyes (16.2 ± 6.0%) due to their more steeply curved laminar surfaces (mean radius of curvature = 1.3 ± 0.1 mm), while the change in pore elongation was comparable to that in normal eyes (-0.2 ± 2.0%). This 3D transformation and tessellation method can be used to better characterize and track 3D changes in laminar pore and surface geometries in glaucoma.

  3. Saccadic Eye Movements in Normal Children from 8 to 15 Years of Age: A Developmental Study of Visuospatial Attention.

    ERIC Educational Resources Information Center

    Ross, Randal G.; And Others

    1994-01-01

    This study used saccadic eye movements to assess visuospatial attention in 53 normal children (ages 8-15). Saccadic latency, the ability to suppress extraneous saccades during fixation, and the ability to inhibit task-provoked anticipatory saccades all improved with age. Developmental patterns varied by task. Analyses of age-related changes may be…

  4. Corneal thickness in dry eyes in an Iraqi population

    PubMed Central

    Ali, Noora Mauwafak; Hamied, Furkaan M; Farhood, Qasim K

    2017-01-01

    Background Dry eye disorder is a multifactorial disease of the tears and ocular surface that results in discomfort and visual disturbance. Corneal pachymetry becomes increasingly important in refractive surgery, for the accurate assessment of intraocular pressure, and in the preoperative assessment of other ocular surgeries. Purpose To assess the effect of dry eye disorder on the central corneal thickness (CCT) by comparing with CCT of normal eyes of age-matched individuals. Patients and methods The total number of eyes examined was 280 (140 dry eyes from 70 patients and 140 normal eyes from 70 individuals). Pentacam (Scheimpflug imaging system) was used for measuring the CCT of all eyes. Results Patients with dry eye syndrome had significantly lower CCT compared to the control group (P<0.01). Its mean was 536.5 versus 561.3, respectively. Conclusion CCT of dry eyes was significantly reduced when compared with age- and gender-matched population. This result can be attributed to chronic desiccation by the inflammatory mediators in dry eyes, leading to corneal thinning. PMID:28260857

  5. Relative contributions of the two eyes to perceived egocentric visual direction in normal binocular vision.

    PubMed

    Sridhar, Deepika; Bedell, Harold E

    2011-05-11

    Perceived egocentric direction (EVD) is based on the sensed position of the eyes in the orbit and the oculocentric visual direction (eye-centered, OVD). Previous reports indicate that in some subjects eye-position information from the two eyes contributes unequally to the perceived EVD. Findings from other studies indicate that the retinal information from the two eyes may not always contribute equally to perceived OVD. The goal of this study was to assess whether these two sources of information covary similarly within the same individuals. Open-loop pointing responses to an isolated target presented randomly at several horizontal locations were collected from 13 subjects during different magnitudes of asymmetric vergence to estimate the contribution of the position information from each eye to perceived EVD. For the same subjects, the direction at which a horizontally or vertically disparate target with different interocular contrast or luminance ratios appeared aligned with a non-disparate target estimated the relative contribution of each eye's retinal information. The results show that the eye-position and retinal information vary similarly in most subjects, which is consistent with a modified version of Hering's law of visual direction.

  6. Expression profile of the matricellular protein osteopontin in primary open-angle glaucoma and the normal human eye.

    PubMed

    Chowdhury, Uttio Roy; Jea, Seung-Youn; Oh, Dong-Jin; Rhee, Douglas J; Fautsch, Michael P

    2011-08-16

    PURPOSE. To characterize the role of osteopontin (OPN) in primary open-angle glaucoma (POAG) and normal eyes. METHODS. OPN quantification was performed by enzyme-linked immunosorbent assay in aqueous humor (AH) obtained from human donor eyes (POAG and normal) and surgical samples (POAG and elective cataract removal). OPN expression and localization in whole eye tissue sections and primary normal human trabecular meshwork (NTM) cells were studied by Western blot and immunohistochemistry. Latanoprost-free acid (LFA)-treated NTM cells were analyzed for OPN gene and protein expression. Intraocular pressure was measured by tonometry, and central corneal thickness was measured by optical coherence tomography in young OPN(-/-) and wild-type mice. RESULTS. OPN levels were significantly reduced in donor POAG AH compared with normal AH (0.54 ± 0.18 ng/μg [n = 8] vs. 0.77 ± 0.23 ng/μg [n = 9]; P = 0.039). A similar trend was observed in surgical AH (1.05 ± 0.31 ng/μg [n = 20] vs. 1.43 ± 0.88 ng/μg [n = 20]; P = 0.083). OPN was present in the trabecular meshwork, corneal epithelium and endothelium, iris, ciliary body, retina, vitreous humor, and optic nerve. LFA increased OPN gene expression, but minimal change in OPN protein expression was observed. No difference in intraocular pressure (17.5 ± 2.0 mm Hg [n = 56] vs. 17.3 ± 1.9 mm Hg [n = 68]) but thinner central corneal thickness (91.7 ± 3.6 μm [n = 50] vs. 99.2 ± 5.5 μm [n = 70]) was noted between OPN(-/-) and wild-type mice. CONCLUSIONS. OPN is widely distributed in the human eye and was found in lower concentrations in POAG AH. Reduction of OPN in young mice does not affect IOP.

  7. Eye-hand coordination in children with high functioning autism and Asperger's disorder using a gap-overlap paradigm.

    PubMed

    Crippa, Alessandro; Forti, Sara; Perego, Paolo; Molteni, Massimo

    2013-04-01

    We investigated eye-hand coordination in children with autism spectrum disorders (ASD) in comparison with age-matched normally developing peers. The eye-hand correlation was measured by putting fixation latencies in relation with pointing and key pressing responses in visual detection tasks where a gap-overlap paradigm was used and compared to fixation latencies in absence of manual response. ASD patients showed less efficient eye-hand coordination, which was particularly evident when pointing towards a target was being fixated. The data of normally developing participants confirmed that manual gap effects are more likely for more complex hand movements. An important discrepancy was discovered in participants with ASD: beside normal eye gap effects, they showed no concurrent hand gap effects when pointing to targets. This result has been interpreted as a further sign of inefficient eye-hand coordination in this patient population.

  8. Comparison of Anterior Segment Biometric Measurements between Pentacam HR and IOLMaster in Normal and High Myopic Eyes

    PubMed Central

    Zhang, Yaqin; Jia, Yading; Zhang, Haining; Jia, Zhijie; Wang, Xiaogang

    2015-01-01

    Purpose To compare the anterior chamber depth (ACD), keratometry (K) and astigmatism measurements taken by IOLMaster and Pentacam HR in normal and high myopic (HM) eyes. Design A prospective observational case series. Methods Sixty-six normal eyes and 59 HM eyes underwent ACD, keratometry and astigmatism measurements with both devices. Axial length (AL) was measured on IOLMaster. The interdevice agreement was evaluated using the Bland-Altman analysis and paired t-test. The correlations between age and AL & ACD were analyzed. Vector analysis was used to compare astigmatism measurements. Results The ACD from IOLMaster and Pentacam HR was different for the normal group (P = 0.003) but not for the HM group (P = 0.280). IOLMaster demonstrated higher steep K and mean K values than Pentacam HR for both normal and HM groups (P<0.001 for all). IOLMaster also have higher flat K values for the HM groups (P<0.001) but were statistically equivalent with Pentacam HR for the normal group (P = 0.119) IOLMaster and Pentacam HR were different in astigmatism measurements for the normal group but were statistically equivalent for the HM group. For the normal group, age was negatively correlated with AL, IOLMaster ACD and Pentacam HR ACD (r = -0.395, P = 0.001; r = -0.715, P < 0.001; r = -0.643, P < 0.001). For the HM group, age was positively correlated with AL but negatively correlated with IOLMaster ACD and Pentacam HR ACD (r = 0.377, P = 0.003; r = -0.392, P = 0.002; r = -0.616, P < 0.001). Conclusions The IOLMaster and Pentacam HR have significant difference in corneal power measurements for both normal and HM groups. The two instruments also differ in ACD and astigmatism measurement for the normal group. Therefore, a single instrument is recommended for studying longitudinal changes in anterior segment biometric measurements. Age should be considered as an influencing factor for both AL and ACD values in the normal and HM group. PMID:26575265

  9. Preface: The aging eye: normal changes, age-related diseases and sight-saving approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This volume presents chapters based on a workshop held on June 14-16, 2013 in Rancho Palos Verde, CA sponsored by the Ocular Research Symposia Foundation (ORSF). The mission of the ORSF is to focus attention on unmet needs and current research opportunities in eye research with the objective of acce...

  10. Comparison of Ethnic-specific Databases in Heidelberg Retina Tomography-3 to Discriminate Between Early Glaucoma and Normal Chinese Eyes

    PubMed Central

    Tan, Xiu Ling; Yap, Sae Cheong; Li, Xiang; Yip, Leonard W.

    2017-01-01

    Purpose: To compare the diagnostic accuracy of the 3 race-specific normative databases in Heidelberg Retina Tomography (HRT)-3, in differentiating between early glaucomatous and healthy normal Chinese eyes. Method: 52 healthy volunteers and 25 glaucoma patients were recruited for this prospective cross-sectional study. All underwent standardized interviews, ophthalmic examination, perimetry and HRT optic disc imaging. Area under the curve (AUC) receiver operating characteristics, sensitivity and specificity were derived to assess the discriminating abilities of the 3 normative databases, for both Moorfields Regression Analysis (MRA) and Glaucoma Probability Score (GPS). Results: A significantly higher percentage (65%) of patients were classified as “within normal limits” using the MRA-Indian database, as compared to the MRA-Caucasian and MRA-African-American databases. However, for GPS, this was observed using the African-American database. For MRA, the highest sensitivity was obtained with both Caucasian and African-American databases (68%), while the highest specificity was from the Indian database (94%). The AUC for discrimination between glaucomatous and normal eyes by MRA-Caucasian, MRA-African-American and MRA-Indian databases were 0.77 (95% CI, 0.67-0.88), 0.79 (0.69-0.89) and 0.73 (0.63-0.84) respectively. For GPS, the highest sensitivity was obtained using either Caucasian or Indian databases (68%). The highest specificity was seen with the African-American database (98%). The AUC for GPS-Caucasian, GPS-African-American and GPS-Indian databases were 0.76 (95% CI, 0.66-0.87), 0.77 (0.67-0.87) and 0.76 (0.66-0.87) respectively. Conclusion: Comparison of the 3 ethnic databases did not reveal significant differences to differentiate early glaucomatous from normal Chinese eyes.

  11. Morphometric measurement of Schlemm's canal in normal human eye using anterior segment swept source optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Shi, Guohua; Wang, Fei; Li, Xiqi; Lu, Jing; Ding, Zhihua; Sun, Xinghuai; Jiang, Chunhui; Zhang, Yudong

    2012-01-01

    We have used anterior segment swept source optical coherence tomography to measure Schlemm's canal (SC) morphometric values in the living human eye. Fifty healthy volunteers with 100 normal eyes were measured in the nasal and temporal side. Comparison with the published SC morphometric values of histologic sections proves the reliability of our results. The statistical results show that there are no significant differences between nasal and temporal SC with respect to their diameter, perimeter, and area in our study (diameter: t=0.122, p=0.903; perimeter: t=-0.003, p=0.998; area: t=-1.169, p=0.244); further, no significant differences in SC morphometric values are found between oculus sinister and oculus dexter (diameter: t=0.943, p=0.35; perimeter: t=1.346, p=0.18; area: t=1.501, p=0.135).

  12. Computed Tomography and Magnetic Resonance Anatomy of the Normal Orbit and Eye of the Horse.

    PubMed

    D'Août, C; Nisolle, J F; Navez, M; Perrin, R; Launois, T; Brogniez, L; Clegg, P; Hontoir, F; Vandeweerd, J M

    2015-10-01

    Traumatic and infectious diseases of the eye and orbit can occur in horses. For diagnosis and monitoring of such diseases, medical imaging is useful including computed tomography (CT) and magnetic resonance imaging (MRI). The aim of the current study was to describe CT and MRI anatomy of the equine orbit and ocular globe. The heads from four adult horses were scanned with a 6-slice Emotion 6 CT (Siemens, Erlangen), and a 3.0 Tesla Siemens Verio 6 MRI using T1 and T2-weighted sequences. To validate CT and MR reference images, these were compared with anatomical models and gross anatomical sections. The bony limits of the orbital cavity, the relationship of the orbit with sinuses and foramina of the skull were well identified by CT. MRI was useful to observe soft tissues and was able to identify adnexae of the ocular globe (eyelids, periorbital fat, extraocular muscles, lacrymal and tarsal glands). Although MRI was able to identify all components of the eye (including the posterior chamber), it could not differentiate sclera from choroid and retina. The only nerve identified was the optic nerve. Vessels were not seen in this series of cadaver heads. This study showed that CT and MRI are useful techniques to image the equine orbit and eye that can have clinical applications.

  13. Postural finger tremor exhibited by Parkinson patients and age-matched subjects.

    PubMed

    Palmer, S S; Hutton, J T

    1995-09-01

    Physiological correlates of postural tremor of the finger seen in Parkinson's disease patients are different from those seen in age-matched control subjects. A significant correlation between the spectral peak of acceleration and the spectral peak of rectified electromyographic activity from the muscle responsible for finger extension was found in Parkinson's disease patients. This correlation was not seen in age-matched control subjects. Any neural drive imposed on the motoneuron pool from supraspinal levels would enhance the electromyographic activity. Likewise, any feedback effects via spinal stretch reflexes or supraspinal stretch responses would be mediated through the motoneuron pool and electromyographic activity. The results of this research support the theory that Parkinson tremor is a centrally driven rhythm that may be influenced by feedback effects, whereas physiological tremor is due to a complex interaction of central, feedback, and mechanical effects.

  14. Studies of the Ability to Hold the Eye in Eccentric Gaze: Measurements in Normal Subjects with the Head Erect

    NASA Technical Reports Server (NTRS)

    Reschke, Millard F.; Somers, Jeffrey T.; Feiveson, Alan H.; Leigh, R. John; Wood, Scott J.; Paloski, William H.; Kornilova, Ludmila

    2006-01-01

    We studied the ability to hold the eyes in eccentric horizontal or vertical gaze angles in 68 normal humans, age range 19-56. Subjects attempted to sustain visual fixation of a briefly flashed target located 30 in the horizontal plane and 15 in the vertical plane in a dark environment. Conventionally, the ability to hold eccentric gaze is estimated by fitting centripetal eye drifts by exponential curves and calculating the time constant (t(sub c)) of these slow phases of gazeevoked nystagmus. Although the distribution of time-constant measurements (t(sub c)) in our normal subjects was extremely skewed due to occasional test runs that exhibited near-perfect stability (large t(sub c) values), we found that log10(tc) was approximately normally distributed within classes of target direction. Therefore, statistical estimation and inference on the effect of target direction was performed on values of z identical with log10t(sub c). Subjects showed considerable variation in their eyedrift performance over repeated trials; nonetheless, statistically significant differences emerged: values of tc were significantly higher for gaze elicited to targets in the horizontal plane than for the vertical plane (P less than 10(exp -5), suggesting eccentric gazeholding is more stable in the horizontal than in the vertical plane. Furthermore, centrifugal eye drifts were observed in 13.3, 16.0 and 55.6% of cases for horizontal, upgaze and downgaze tests, respectively. Fifth percentile values of the time constant were estimated to be 10.2 sec, 3.3 sec and 3.8 sec for horizontal, upward and downward gaze, respectively. The difference between horizontal and vertical gazeholding may be ascribed to separate components of the velocity position neural integrator for eye movements, and to differences in orbital mechanics. Our statistical method for representing the range of normal eccentric gaze stability can be readily applied in a clinical setting to patients who were exposed to environments

  15. Dendritic cells and macrophages in the uveal tract of the normal mouse eye

    PubMed Central

    McMenamin, P.

    1999-01-01

    BACKGROUND/AIMS—Dendritic cells (DC) and macrophages are components of the immune cell populations in the uveal tract whose density, distribution, turnover, and function may play a role in the maintenance of immunological homeostasis in the eye. Little is known of these cells in the mouse eye despite this being the predominant experimental model in many studies of ocular immune responses and immunoinflammatory mediated eye diseases. The aim of the present study was to obtain further immunophenotypic data on resident tissue macrophages and DC populations in the mouse uveal tract.
METHODS—Pieces of iris, ciliary body, and choroid dissected from perfusion fixed BALB/c mice were incubated whole in a variety of anti-macrophage and DC monoclonal antibodies (mAbs). Labelled cells were visualised using either single or double immunoperoxidase techniques.
RESULTS—Quantitative analysis and double immunolabelling revealed that 80% of F4/80+ cells (a mAb that recognises both DC and macrophages) in the iris are macrophages (SER4+). The iris contained a network of Ia+ cells (412 (SD 130) cells/mm2) of which two thirds appear to be DC. A similar pattern was observed in the ciliary body and choroid. Only a few DC in the uveal tract were very weakly reactive for mAbs which recognise B7-1 (CD80), B7-2 (CD86), β2 integrin (mAb N418), and multivesicular bodies associated with antigen presentation (mAb M342).
CONCLUSIONS—The present study reveals that the mouse uveal tract, like the rat, contains rich networks of DC and resident tissue macrophages. The networks of resident tissue macrophages in the mouse uveal tract closely resemble similar networks in non-ocular tissues. The phenotype of uveal tract DC suggests they are in the "immature" phase of their life cycle, similar to Langerhans cells of the skin, thus implying their role in situ within the eye is antigen capture and not antigen presentation.

 PMID:10216062

  16. Heterogeneity of SPECT bull`s-eyes in normal dogs: Comparison of attenuation compensation algorithms

    SciTech Connect

    DiBella, E.V.R.; Eisner, R.L.; Schmarkey, L.S.; Barclay, A.B.; Patterson, R.E.; Nowak, D.J.; Lalush, D.S.; Tsui, B.M.W. ||

    1995-08-01

    In normal dogs, SPECT {sup 99m}Tc Sestamibi (MIBI) and {sup 201}Tl myocardial perfusion images reconstructed with filtered backprojection (FBP) show a large decrease of counts in the septal wall (S) compared to the lateral wall (L). The authors evaluated the iterative method of Chang at 0 and 1 iterations (Chang0 and Chang1), and the Maximum Likelihood-Expectation Maximization with attenuation compensation (ML-EM-ATN) algorithm on data acquired from 5 normal dogs and from simulated projection data using a homogeneous count-density model of a normal canine myocardium in the attenuation field measured in one dog. Mean counts in the S and L regions were calculated from maximum-count circumferential profile arrays. Their results demonstrate that ML-EM-ATN and Chang1 result in improved uniformity, as measured by the S/L ratio.

  17. Comparison of choroidal thickness measurements between spectral-domain OCT and swept-source OCT in normal and diseased eyes

    PubMed Central

    Zafar, Sidra; Siddiqui, MA Rehman; Shahzad, Rida

    2016-01-01

    Purpose Sub-foveal choroidal thickness (SFCT) is affected in many ocular diseases. The aim of this study was to compare SFCT measurements between Topcon 3D 2000 spectral-domain optical coherence tomography (SD-OCT) and Topcon swept-source OCT (SS-OCT), with different laser wavelengths, in normal and diseased populations. Materials and methods This was a prospective, cross-sectional, noninterventional study including 27 normal volunteers and 27 participants with retinal disease. OCT scans were performed sequentially and under standardized conditions using both SD-OCT and SS-OCT. The OCT scans were evaluated by two independent graders. Paired t-tests and intraclass correlation coefficients (ICCs) were used to assess the statistically significant difference between SFCT measurements as measured by the two devices. Results Mean SFCT measurements for all 54 participants were 264.9±103.1 μm using SD-OCT (range: 47–470 μm) and 278.5±110.5 μm using SS-OCT (range: 56–502 μm), with an inter-device ICC of 0.850. Greater variability was noted in the diseased eyes. Inter-device ICCs were 0.870 (95% CI; 0.760–0.924) and 0.840 (95% CI; 0.654–0.930) for normal and diseased eyes, respectively. However, the difference was not statistically significant (P=0.132). Conclusion Both machines reliably measure SFCT. Larger studies are needed to confirm these findings. PMID:27881909

  18. Light scattering study of the normal human eye lens: Elastic properties and age dependence

    PubMed Central

    Bailey, Sheldon T.; Twa, Michael D.; Gump, Jared C.; Venkiteshwar, Manoj; Bullimore, Mark A.

    2015-01-01

    The human ocular lens is a tissue capable of changing its shape to dynamically adjust the optical power of the eye, a function known as accommodation, which gradually declines with age. This capability is the response of the lens tissue to external forces which, in turn, is modulated by the biomechanical characteristics of lens tissues. In order to investigate the contributions of lens sclerosis to loss of accommodation, we report on in vitro confocal Brillouin light scattering studies of human ocular lenses spanning over a 30-70 year age range. Using this non-destructive measurement method, we determined that the longitudinal bulk modulus (average ± SD) of the lens nucleus (2.79±0.14 GPa) was consistently greater than the bulk modulus of the lens cortex (2.36±0.09 GPa). Moreover, our results showed that these differences were not age dependent over the 40 year age range that we evaluated using healthy lens tissues. Our results are consistent with the hypothesis that an age-dependent change in the bulk modulus of lens tissues does not fully account for the natural decline of accommodation. PMID:20529725

  19. Prevalence of temporomandibular disorder pain in Chinese adolescents compared to an age-matched Swedish population.

    PubMed

    Hongxing, L; Astrøm, A N; List, T; Nilsson, I-M; Johansson, A

    2016-04-01

    This study aimed to (i) assess the prevalence and perceived need for treatment of TMD pain, and its association with socio-economic factors and gender, in adolescents in Xi᾽an, Shaanxi Province, China, and (ii) compare the prevalence and association with gender of TMD pain in Xi᾽an to an age-matched Swedish population. We surveyed Chinese adolescents aged 15 to 19 years in Xi'an, China (n = 5524), using a questionnaire with two-stage stratified sampling and the school as the sampling unit. The study included second-year students at selected high schools. It also included an age-matched Swedish population (n = 17,015) surveyed using the same diagnostic criteria for TMD pain as that used in the Chinese sample. The survey found TMD pain in 14·8% (n = 817) of the Chinese sample and 5·1% (n = 871) of the Swedish sample (P < 0·0001). Girls had significantly more TMD pain than boys in both the Chinese (P < 0·05) and Swedish (P < 0·001) samples. TMD pain increased with age in the Chinese population. Of the Chinese adolescents with TMD pain, 47% reported that they felt a need for treatment. Rural schools, low paternal education levels, poverty, living outside the home, poor general and oral health, and dissatisfaction with teeth all showed significant positive correlations with TMD pain. Prevalence of TMD pain in Chinese adolescents was significantly higher than in the Swedish sample.

  20. A proteomic study of protein variation between osteopenic and age-matched control bone tissue.

    PubMed

    Chaput, Christopher D; Dangott, Lawrence J; Rahm, Mark D; Hitt, Kirby D; Stewart, Donald S; Wayne Sampson, H

    2012-05-01

    The focus of this study was to identify changes in protein expression within the bone tissue environment between osteopenic and control bone tissue of human femoral neck patients with osteoarthritis. Femoral necks were compared from osteopenic patients and age-matched controls. A new method of bone protein extraction was developed to provide a swift, clear view of the bone proteome. Relative changes in protein expression between control and osteopenic samples were quantified using difference gel electrophoresis (DIGE) technology after affinity chromatographic depletion of albumin and IgG. The proteins that were determined to be differentially expressed were identified using standard liquid chromatography mass spectrometry (LC/MS/MS) and database searching techniques. In order to rule out blood contamination, blood from age-matched osteoporotic, osteopenic and controls were analyzed in a similar manner. Image analysis of the DIGE gels indicated that 145 spots in the osteopenic bone samples changed at least ± 1.5-fold from the control samples (P < 0.05). Three of the proteins were identified by LC/MS/MS. Of the proteins that increased in the osteopenic femurs, two were especially significant: carbonic anhydrase I and phosphoglycerate kinase 1. Apolipoprotein A-I was the most prominent protein that significantly decreased in the osteopenic femurs. The blood samples revealed no significant differences between groups for any of these proteins. In conclusion, carbonic anhydrase I, phosphoglycerate kinase 1 and apolipoprotein A-I appeared to be the most significant variations of proteins in patients with osteopenia and osteoarthritis.

  1. Comparison of Brachial Artery Vasoreactivity in Elite Power Athletes and Age-Matched Controls

    PubMed Central

    Welsch, Michael A.; Blalock, Paul; Credeur, Daniel P.; Parish, Tracie R.

    2013-01-01

    Elite endurance athletes typically have larger arteries contributing to greater skeletal muscle blood flow, oxygen and nutrient delivery and improved physical performance. Few studies have examined structural and functional properties of arteries in power athletes. Purpose To compare the size and vasoreactivity of the brachial artery of elite power athletes to age-matched controls. It was hypothesized brachial artery diameters of athletes would be larger, have less vasodilation in response to cuff occlusion, but more constriction after a cold pressor test than age-matched controls. Methods Eight elite power athletes (age = 23±2 years) and ten controls (age = 22±1 yrs) were studied. High-resolution ultrasonography was used to assess brachial artery diameters at rest and following 5 minutes of forearm occlusion (Brachial Artery Flow Mediated Dilation = BAFMD) and a cold pressor test (CPT). Basic fitness measures included a handgrip test and 3-minute step test. Results Brachial arteries of athletes were larger (Athletes 5.39±1.51 vs. Controls: 3.73±0.71 mm, p<0.05), had greater vasodilatory (BAFMD%: Athletes: 8.21±1.78 vs. Controls: 5.69±1.56%) and constrictor (CPT %: Athletes: -2.95±1.07 vs. Controls: −1.20±0.48%) responses, compared to controls. Vascular operating range (VOR = Peak dilation+Peak Constriction) was also greater in athletes (VOR: Athletes: 0.55±0.15 vs. Controls: 0.25±0.18 mm, p<0.05). Athletes had superior handgrip strength (Athletes: 55.92±17.06 vs. Controls: 36.77±17.06 kg, p<0.05) but similar heart rate responses at peak (Athletes: 123±16 vs. Controls: 130±25 bpm, p>0.05) and 1 minute recovery (Athletes: 88±21 vs. Controls: 98±26 bpm, p>0.05) following the step test. Conclusion Elite power athletes have larger brachial arteries, and greater vasoreactivity (greater vasodilatory and constrictor responses) than age-matched controls, contributing to a significantly greater VOR. These data extend the existence of an

  2. Biophysical and Morphological Evaluation of Human Normal and Dry Eye Meibum Using Hot Stage Polarized Light Microscopy

    PubMed Central

    Butovich, Igor A.; Lu, Hua; McMahon, Anne; Ketelson, Howard; Senchyna, Michelle; Meadows, David; Campbell, Elaine; Molai, Mike; Linsenbardt, Emily

    2014-01-01

    Purpose. To study melting characteristics and the morphology of human and mouse meibum. Methods. Hot stage cross-polarized light microscopy (HSPM) and immunohistochemical approaches were used. Results. Isolated human meibum, and meibum of mice (either isolated or within the meibomian ducts of mice), were found to be in liquid-crystal state at physiological temperatures. Melting of both types of meibum started at approximately 10°C and was completed at approximately 40°C. Melting curves of isolated meibum and meibum inside the meibomian ducts were multiphasic with at least two or three clearly defined phase transition temperatures, typically at approximately 12 ± 2°C (minor transition), 21 ± 3°C, and 32 ± 3°C, regardless the source of meibum. Melting was highly cooperative in nature. Samples of abnormal human meibum collected from dry eye patients with meibomian gland dysfunction often showed an increased presence of nonlipid, nonmelting, nonbirefringent, chloroform-insoluble inclusions of a protein nature. The inclusions were positively stained for cytokeratins. The presence of these inclusions was semiquantitatively characterized using a newly proposed 0 to 4 scale. In the presence of large amounts of these inclusions, melting characteristics of meibum and its structural integrity were altered. Conclusions. HSPM is an effective tool that is suitable for biophysical and morphological evaluation of meibum. Morphological properties and melting characteristics of human meibum were found to be similar to those of mice. Abnormal meibum of many dry eye patients contained large quantities of nonlipid, protein-like inclusions, which were routinely absent in meibum of normal controls. PMID:24282231

  3. A Comparison of Substantia Nigra T1 Hyperintensity in Parkinson's Disease Dementia, Alzheimer's Disease and Age-Matched Controls: Volumetric Analysis of Neuromelanin Imaging

    PubMed Central

    Park, Ju-Yeon; Yun, Won-Sung; Jeon, Ji Yeong; Moon, Yeon Sil; Kim, Heejin; Kwak, Ki-Chang; Lee, Jong-Min; Han, Seol-Heui

    2016-01-01

    Objective Neuromelanin loss of substantia nigra (SN) can be visualized as a T1 signal reduction on T1-weighted high-resolution imaging. We investigated whether volumetric analysis of T1 hyperintensity for SN could be used to differentiate between Parkinson's disease dementia (PDD), Alzheimer's disease (AD) and age-matched controls. Materials and Methods This retrospective study enrolled 10 patients with PDD, 18 patients with AD, and 13 age-matched healthy elderly controls. MR imaging was performed at 3 tesla. To measure the T1 hyperintense area of SN, we obtained an axial thin section high-resolution T1-weighted fast spin echo sequence. The volumes of interest for the T1 hyperintense SN were drawn onto heavily T1-weighted FSE sequences through midbrain level, using the MIPAV software. The measurement differences were tested using the Kruskal-Wallis test followed by a post hoc comparison. Results A comparison of the three groups showed significant differences in terms of volume of T1 hyperintensity (p < 0.001, Bonferroni corrected). The volume of T1 hyperintensity was significantly lower in PDD than in AD and normal controls (p < 0.005, Bonferroni corrected). However, the volume of T1 hyperintensity was not different between AD and normal controls (p = 0.136, Bonferroni corrected). Conclusion The volumetric measurement of the T1 hyperintensity of SN can be an imaging marker for evaluating neuromelanin loss in neurodegenerative diseases and a differential in PDD and AD cases. PMID:27587951

  4. Eye muscle repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100062.htm Eye muscle repair - series—Normal anatomy To use the sharing ... the eyeball to the eye socket. The external muscles of the eye are found behind the conjunctiva. ...

  5. Comparison of central corneal thickness measurements using ultrasound pachymetry, ultrasound biomicroscopy, and the Artemis-2 VHF scanner in normal eyes

    PubMed Central

    Al-Farhan, Haya M; Al-Otaibi, Wafa’a Majed

    2012-01-01

    Purpose To compare the precision of central corneal thickness (CCT) measurements taken with the handheld ultrasound pachymeter (USP), ultrasound biomicroscopy (UBM), and the Artemis-2 very high frequency ultrasound scanner (VHFUS) on normal subjects. Design Prospective study. Methods One eye from each of 61 normal subjects was randomly selected for this study. The measurements of the CCT were taken with the USP, VHFUS, and UBM. Results were compared statistically using repeated-measures analysis of variance (ANOVA), Pearson’s correlation coefficient, and limits of agreement. Results The average CCT (± standard deviation) was 530.1 ± 30.5 μm, 554.9 ± 31.7 μm, and 559.5 ± 30.7 μm for UBM, VHFUS, and USP respectively. The intraobserver repeatability analyses of variance are not significant for USP, UBM, and VHFUS. P-values were 0.17, 0.19, and 0.37 respectively. Repeated-measures ANOVA showed a significant difference between the three different methods of measuring CCT (P = 0.0001). The ANOVA test revealed no statistically significant difference between USP and VHFUS (P > 0.05), yet statistical significant differences with UBM versus USP and UBM versus VHFUS (P < 0.001). There were high correlations between the three instruments (P < 0.0001). The mean differences (and upper/lower limits of agreement) for CCT measurements were 29.4 ± 14.3 (2.7/56), 4.6 ± 8.6 (−14.7/23.8), and −24.8 ± 13.1 (−50.4/0.8) for USP versus UBM, USP versus VHFUS, and UBM versus VHFUS, respectively. Conclusion The UBM produces CCT measurements that vary significantly from those returned by the USP and the VHFUS, suggesting that the UBM may not be used interchangeably with either equipment for monitoring the CCT in the clinical setting. PMID:22848145

  6. Cardiovascular function is better in veteran football players than age-matched untrained elderly healthy men.

    PubMed

    Schmidt, J F; Andersen, T R; Andersen, L J; Randers, M B; Hornstrup, T; Hansen, P R; Bangsbo, J; Krustrup, P

    2015-02-01

    The aim of the study was to determine whether lifelong football training may improve cardiovascular function, physical fitness, and body composition. Our subjects were 17 male veteran football players (VPG; 68.1 ± 2.1 years) and 26 healthy age-matched untrained men who served as a control group (CG; 68.2 ± 3.2 years). Examinations included measurements of cardiac function, microvascular endothelial function [reactive hyperemic index (RHI)], maximum oxygen uptake (VO2max), and body composition. In VPG, left ventricular (LV) end-diastolic volume was 20% larger (P < 0.01) and LV ejection fraction was higher (P < 0.001). Tissue Doppler imaging revealed an augmented LV longitudinal displacement, i.e., LV shortening of 21% (P < 0.001) and longitudinal 2D strain was 12% higher (P < 0.05), in VPG. In VPG, resting heart rate was lower (6 bpm, P < 0.05), and VO2max was higher (18%, P < 0.05). In addition, RHI was 21% higher (P < 0.05) in VPG. VPG also had lower body mass index (P < 0.05), body fat percentage, total body fat mass, android fat percentage, and gynoid fat percentage (all P < 0.01). Lifelong participation in football training is associated with better LV systolic function, physical fitness, microvascular function, and a healthier body composition. Overall, VPG have better cardiovascular function compared with CG, which may reduce their cardiovascular morbidity and mortality.

  7. Developmental Level and Psychopathology: Comparing Children with Developmental Delays to Chronological and Mental Age Matched Controls

    PubMed Central

    Caplan, Barbara; Neece, Cameron L.; Baker, Bruce L.

    2015-01-01

    Children with developmental delays (DD) are at heightened risk for developing clinically significant behavioral and emotional difficulties as compared to children with typical development (TD). However, nearly all studies comparing psychopathology in youth with DD employ TD control groups of the same chronological age (CA). It is unclear, then, whether the heightened symptomology found in age-matched children with DD is beyond what would be expected given their developmental level. The present study assessed rates of behavior problems and mental disorder in 35 children with DD at age 9 years. These were compared with rates from 35 children with TD matched for CA at age 9 and also earlier rates for these same children at age 6, when matched for mental age (MA). Children with DD had significantly more behavior problems in 7 of the 17 scales of the CBCL when compared to TD children matched for CA, and 6 of 17 scales when compared to the MA-matched group. Rates of meeting DSM-IV criteria for a psychiatric disorder were significantly higher in the DD group than both the CA- and MA-matched TD groups for three and four, respectively, of the seven diagnoses examined. Descriptively, the mean ratings for all variables assessed were higher for the DD group than both TD comparison groups, with the exception of the Anxious/Depressed scale of the CBCL. These findings validate the heightened risk for clinically significant behavior problems and mental disorders in youth with DD above and beyond their developmental functioning. PMID:25498740

  8. ABCB1 genotypes and haplotypes in patients with dementia and age-matched non-demented control patients

    PubMed Central

    Frankfort, Suzanne V; Doodeman, Valerie D; Bakker, Remco; Tulner, Linda R; van Campen, Jos PCM; Smits, Paul HM; Beijnen, Jos H

    2006-01-01

    Amyloid β is an in vitro substrate for P-glycoprotein (P-gp), an efflux pump at the blood brain barrier (BBB). The Multi Drug Resistance (ABCB1) gene, encoding for P-gp, is highly polymorphic and this may result in a changed function of P-gp and may possibly interfere with the pathogenesis of Alzheimer's disease. This study investigates to what extent ABCB1 Single Nucleotide Polymorphisms (SNPs; C1236T in exon 12, G2677T/A in exon 21 and C3435T in exon 26) and inferred haplotypes exist in an elderly population and if these SNPs and haplotypes differ between patients with dementia and age-matched non-demented control patients. ABCB1 genotype, allele and haplotype frequencies were neither significantly different between patients with dementia and age-matched controls, nor between subgroups of different types of dementia nor age-matched controls. This study shows ABCB1 genotype frequencies to be comparable with described younger populations. To our knowledge this is the first study on ABCB1 genotypes in dementia. ABCB1 genotypes are presently not useful as a biomarker for dementia, as they were not significantly different between demented patients and age-matched control subjects. PMID:16999857

  9. Comparison of Conditioning Impairments in Children with Down Syndrome, Autistic Spectrum Disorders and Mental Age-Matched Controls

    ERIC Educational Resources Information Center

    Reed, P.; Staytom, L.; Stott, S.; Truzoli, R.

    2011-01-01

    Background: This study investigated the relative ease of learning across four tasks suggested by an adaptation of Thomas's hierarchy of learning in children with Down syndrome, autism spectrum disorders and mental age-matched controls. Methods: Learning trials were carried out to investigate observational learning, instrumental learning, reversal…

  10. CD25+CD127+Foxp3- Cells Represent a Major Subpopulation of CD8+ T Cells in the Eye Chambers of Normal Mice

    PubMed Central

    Ziółkowska, Natalia; Ziółkowski, Hubert; Małaczewska, Joanna

    2017-01-01

    The aim of this study has been to determine whether eye chambers constitute part of the normal migratory pathway of naive CD4+ and CD8+ T cells in mouse and if natural CD4+CD25+Foxp3+ and CD8+CD25+Foxp3+ regulatory T cells are present within these eye compartments. To this aim, the cells obtained from aqueous humor (AH) of normal mice were phenotyped in terms of the expression CD4, CD8, CD25, CD127 and transcription factor Foxp3. The mean percentage of CD8+ T cells in the total AH lymphocyte population was as high as 28.69%; the mean percentage of CD8high and CD8low cells in this population was 34.09% and 65.91%, respectively. The presence of cells with the regulatory phenotype, i.e. CD25+Foxp3+ cells, constituted only 0.32% of CD8+ T cell subset. Regarding the expression of CD25, AH CD8+ T cells were an exceptional population in that nearly 85% of these cells expressed this molecule without concomitant Foxp3 expression. Despite having this phenotype, they should not be viewed as activated cells because most of them co-expressed CD127, which indicates that they are naive lymphocytes. With regard to the markers applied in the present research, CD8+CD25+CD127+Foxp3- T cells represent the most numerous subset of AH CD8+ cells. The results suggest that eye chambers in mice are an element in the normal migratory pathway of naive CD8+ T cells. The study presented herein demonstrated only trace presence of CD4+ cells in the eye chambers, as the mean percentage of these cells was just 0.56. Such selective and specific homing of CD8+ and CD4+ cells to the eye chambers is most clearly engaged in the induction and maintenance of ocular immune privilege. PMID:28081241

  11. Symmetry Between the Right and Left Eyes of the Normal Retinal Nerve Fiber Layer Measured with Optical Coherence Tomography (An AOS Thesis)

    PubMed Central

    Budenz, Donald L.

    2008-01-01

    Purpose To determine the limits of the normal amount of interocular symmetry in retinal nerve fiber layer (RNFL) thickness measurements obtained with third-generation time domain optical coherence tomography (OCT3). Methods Both eyes of normal volunteers were scanned using the peripapillary standard and fast RNFL algorithms of OCT3. Results A total of 108 volunteers were included in the analysis. The mean ± standard deviation (SD) of age of the volunteers was 46.0 ± 15.0 years (range 20–82). Forty-two participants (39%) were male and 66 (61%) were female. Mean RNFL thickness correlated extremely well, with intraclass correlation coefficients of 0.89 for both algorithms (95% confidence interval [CI], 0.84–0.93). The mean RNFL thickness of the right eye measured 1.3 μm thicker than the left on the standard scan (SD 4.7, 95% CI 0.4–2.2, P = .004) and 1.2 μm on the fast scan (SD 5.2, 95% CI 0.1–2.2, P = .026). The 95% tolerance limits on the difference between the mean RNFL thicknesses of right minus left eye was −10.8 and +8.9 μm with the standard scan algorithm and −10.6 and +11.7 μm with the fast scan algorithm. Conclusions Mean RNFL thickness between the 2 eyes of normal individuals should not differ by more than approximately 9 to 12 μm, depending on which scanning algorithm of OCT3 is used and which eye measures thicker. Differences beyond this level suggest statistically abnormal asymmetry, which may represent early glaucomatous optic neuropathy. PMID:19277241

  12. Repeatability and Reproducibility of Retinal Nerve Fiber Layer Parameters Measured by Scanning Laser Polarimetry with Enhanced Corneal Compensation in Normal and Glaucomatous Eyes

    PubMed Central

    Ara, Mirian; Ferreras, Antonio; Pajarin, Ana B.; Calvo, Pilar; Figus, Michele; Frezzotti, Paolo

    2015-01-01

    Objective. To assess the intrasession repeatability and intersession reproducibility of peripapillary retinal nerve fiber layer (RNFL) thickness parameters measured by scanning laser polarimetry (SLP) with enhanced corneal compensation (ECC) in healthy and glaucomatous eyes. Methods. One randomly selected eye of 82 healthy individuals and 60 glaucoma subjects was evaluated. Three scans were acquired during the first visit to evaluate intravisit repeatability. A different operator obtained two additional scans within 2 months after the first session to determine intervisit reproducibility. The intraclass correlation coefficient (ICC), coefficient of variation (COV), and test-retest variability (TRT) were calculated for all SLP parameters in both groups. Results. ICCs ranged from 0.920 to 0.982 for intravisit measurements and from 0.910 to 0.978 for intervisit measurements. The temporal-superior-nasal-inferior-temporal (TSNIT) average was the highest (0.967 and 0.946) in normal eyes, while nerve fiber indicator (NFI; 0.982) and inferior average (0.978) yielded the best ICC in glaucomatous eyes for intravisit and intervisit measurements, respectively. All COVs were under 10% in both groups, except NFI. TSNIT average had the lowest COV (2.43%) in either type of measurement. Intervisit TRT ranged from 6.48 to 12.84. Conclusions. The reproducibility of peripapillary RNFL measurements obtained with SLP-ECC was excellent, indicating that SLP-ECC is sufficiently accurate for monitoring glaucoma progression. PMID:26185762

  13. Assessment of Choroidal Microstructure and Subfoveal Thickness Change in Eyes With Different Stages of Age-Related Macular Degeneration

    PubMed Central

    Lu, Linna; Xu, Shiqiong; He, Fangling; Liu, Yan; Zhang, Yidan; Wang, Jing; Wang, Zhiliang; Fan, Xianqun

    2016-01-01

    Abstract Age-related macular degeneration (AMD) is a major cause of irreversible blindness. Choroidal structural changes seem to be inevitable in AMD pathogenesis. Our study revealed associated choroidal microstructural changes in AMD eyes. The aim of the study was to compare choroidal microstructural changes in eyes with AMD of different stages. The study was a retrospective, cross-sectional case series. The participants comprised of 32 age-matched normal eyes as controls, and 26 fellow uninvolved eyes of intermediate/late AMD, 29 of early AMD, 28 of intermediate AMD, and 39 of late AMD. All subjects underwent comprehensive ophthalmologic examination. The choroid images, including subfoveal choroidal thickness, percentage of Sattler layer area, and en face images of the choroid, were obtained using spectral-domain optical coherence tomography. The main outcome measures were subfoveal choroidal thickness changes, percentage of Sattler layer area changes, and en face images of the choroid in AMD eyes. One hundred fifty-four eyes of 96 individuals with mean age of 67.1±9.2 years were included. The mean subfoveal choroidal thickness was 295.4 ± 56.8 μm in age-matched normal eyes, 306.7 ± 68.4 μm in fellow uninvolved eyes with AMD, 293.8 ± 80.4 μm in early AMD, 215.6 ± 80.4 μm in intermediate AMD, and 200.4 ± 66.6 μm in late AMD (F = 14.2, all P < 0.001). Choroidal thickness was greater in early AMD eyes than in intermediate/late AMD eyes (P < 0.001). Mean percentage of Sattler layer area in each group showed a similar tendency. Microstructure of the choroid showed reduced vascular density of Sattler layer areas in late AMD eyes compared with normal eyes. Decreasing subfoveal choroidal thickness and percentage of Sattler layer area were demonstrated in the progression of AMD. The choroidal change was related to atrophy of the microstructural changes of underlying capillaries and medium-sized vessels. PMID:26962799

  14. Eye-Voice Span during Rapid Automatized Naming of Digits and Dice in Chinese Normal and Dyslexic Children

    ERIC Educational Resources Information Center

    Pan, Jinger; Yan, Ming; Laubrock, Jochen; Shu, Hua; Kliegl, Reinhold

    2013-01-01

    We measured Chinese dyslexic and control children's eye movements during rapid automatized naming (RAN) with alphanumeric (digits) and symbolic (dice surfaces) stimuli. Both types of stimuli required identical oral responses, controlling for effects associated with speech production. Results showed that naming dice was much slower than naming…

  15. Evaluation of Central Corneal Thickness Using Corneal Dynamic Scheimpflug Analyzer Corvis ST and Comparison with Pentacam Rotating Scheimpflug System and Ultrasound Pachymetry in Normal Eyes

    PubMed Central

    Yu, Ayong; Zhao, Weiqi; Savini, Giacomo; Huang, Zixu; Bao, Fangjun; Lu, Weicong; Wang, Qinmei; Huang, Jinhai

    2015-01-01

    Purpose. To assess the repeatability and reproducibility of central corneal thickness (CCT) measurements by corneal dynamic Scheimpflug analyzer Corvis ST in normal eyes and compare the agreement with Pentacam rotating Scheimpflug System and ultrasound pachymetry. Methods. 84 right eyes underwent Corvis ST measurements performed by two operators. The test-retest repeatability (TRT), within-subject coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were used to evaluate the intraoperator repeatability and interoperator reproducibility. CCT measurements also were obtained from Pentacam and ultrasound pachymetry by the first operator. The agreement between the three devices was evaluated with 95% limits of agreement (LoA) and Bland-Altman plots. Results. Corvis ST showed high repeatability as indicated by TRT ≤ 13.0 μm, CoV < 0.9%, and ICC > 0.97. The interoperator reproducibility was also excellent. The CoV was <0.9%, and ICC was >0.97. Corvis ST showed significantly lower values than Pentacam and ultrasound pachymetry (P < 0.001). The 95% LoA between Corvis ST and Pentacam or ultrasound pachymetry were −15.8 to 9.5 μm and −27.9 to 12.3 μm, respectively. Conclusions. Corvis ST showed excellent repeatability and interoperator reproducibility of CCT measurements in normal eyes. Corvis ST is interchangeable with Pentacam but not with ultrasound pachymetry. PMID:26697213

  16. Evaluation of Central Corneal Thickness Using Corneal Dynamic Scheimpflug Analyzer Corvis ST and Comparison with Pentacam Rotating Scheimpflug System and Ultrasound Pachymetry in Normal Eyes.

    PubMed

    Yu, Ayong; Zhao, Weiqi; Savini, Giacomo; Huang, Zixu; Bao, Fangjun; Lu, Weicong; Wang, Qinmei; Huang, Jinhai

    2015-01-01

    Purpose. To assess the repeatability and reproducibility of central corneal thickness (CCT) measurements by corneal dynamic Scheimpflug analyzer Corvis ST in normal eyes and compare the agreement with Pentacam rotating Scheimpflug System and ultrasound pachymetry. Methods. 84 right eyes underwent Corvis ST measurements performed by two operators. The test-retest repeatability (TRT), within-subject coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were used to evaluate the intraoperator repeatability and interoperator reproducibility. CCT measurements also were obtained from Pentacam and ultrasound pachymetry by the first operator. The agreement between the three devices was evaluated with 95% limits of agreement (LoA) and Bland-Altman plots. Results. Corvis ST showed high repeatability as indicated by TRT ≤ 13.0 μm, CoV < 0.9%, and ICC > 0.97. The interoperator reproducibility was also excellent. The CoV was <0.9%, and ICC was >0.97. Corvis ST showed significantly lower values than Pentacam and ultrasound pachymetry (P < 0.001). The 95% LoA between Corvis ST and Pentacam or ultrasound pachymetry were -15.8 to 9.5 μm and -27.9 to 12.3 μm, respectively. Conclusions. Corvis ST showed excellent repeatability and interoperator reproducibility of CCT measurements in normal eyes. Corvis ST is interchangeable with Pentacam but not with ultrasound pachymetry.

  17. Assessment of Optical Quality at Different Contrast Levels in Pseudophakic Eyes

    PubMed Central

    Park, Chang Won; Kim, Hyojin; Joo, Choun-Ki

    2016-01-01

    Purpose. To assess visual function using Optical Quality Analysis System (OQAS) at varying levels of contrast in pseudophakic eyes. Methods. The study included patients admitted to Seoul St. Mary's Hospital between January and February 2012: 143 pseudophakic eyes with one of five intraocular lens types, examined 2–6 months after cataract surgery, and 93 normal eyes (enhanced visual acuity (VA) < 0.1 logMAR) in age-matched controls. Subjects were examined at three contrast levels using the OQAS. Results. At 100%, 20%, and 9% contrast, simulated mean VA was 0.16 ± 0.18 logMAR, 0.30 ± 0.18 logMAR, and 0.52 ± 0.17 logMAR, in normal eyes, and 0.16 ± 0.12 logMAR, 0.33 ± 0.20 logMAR, and 0.56 ± 0.21 logMAR, respectively, in pseudophakic eyes. Simulated VA decreased significantly when contrast was reduced, regardless of ocular status, age group, and lens type (p < 0.05). There were no significant differences between normal and pseudophakic eyes among subjects aged 50–69 (p > 0.05). Among subjects aged 70–79, pseudophakic eyes showed improved simulated VA (p = 0.000) and objective scattering index values (p = 0.008). Conclusions. Patients with intraocular lenses have similar or superior visual function when compared to those with normal eyes at 2–6 months after cataract surgery, even under low-contrast conditions. PMID:27057349

  18. Computational fluid dynamics assisted characterization of parafoveal hemodynamics in normal and diabetic eyes using adaptive optics scanning laser ophthalmoscopy.

    PubMed

    Lu, Yang; Bernabeu, Miguel O; Lammer, Jan; Cai, Charles C; Jones, Martin L; Franco, Claudio A; Aiello, Lloyd Paul; Sun, Jennifer K

    2016-12-01

    Diabetic retinopathy (DR) is the leading cause of visual loss in working-age adults worldwide. Previous studies have found hemodynamic changes in the diabetic eyes, which precede clinically evident pathological alterations of the retinal microvasculature. There is a pressing need for new methods to allow greater understanding of these early hemodynamic changes that occur in DR. In this study, we propose a noninvasive method for the assessment of hemodynamics around the fovea (a region of the eye of paramount importance for vision). The proposed methodology combines adaptive optics scanning laser ophthalmoscopy and computational fluid dynamics modeling. We compare results obtained with this technique with in vivo measurements of blood flow based on blood cell aggregation tracking. Our results suggest that parafoveal hemodynamics, such as capillary velocity, wall shear stress, and capillary perfusion pressure can be noninvasively and reliably characterized with this method in both healthy and diabetic retinopathy patients.

  19. Computational fluid dynamics assisted characterization of parafoveal hemodynamics in normal and diabetic eyes using adaptive optics scanning laser ophthalmoscopy

    PubMed Central

    Lu, Yang; Bernabeu, Miguel O.; Lammer, Jan; Cai, Charles C.; Jones, Martin L.; Franco, Claudio A.; Aiello, Lloyd Paul; Sun, Jennifer K.

    2016-01-01

    Diabetic retinopathy (DR) is the leading cause of visual loss in working-age adults worldwide. Previous studies have found hemodynamic changes in the diabetic eyes, which precede clinically evident pathological alterations of the retinal microvasculature. There is a pressing need for new methods to allow greater understanding of these early hemodynamic changes that occur in DR. In this study, we propose a noninvasive method for the assessment of hemodynamics around the fovea (a region of the eye of paramount importance for vision). The proposed methodology combines adaptive optics scanning laser ophthalmoscopy and computational fluid dynamics modeling. We compare results obtained with this technique with in vivo measurements of blood flow based on blood cell aggregation tracking. Our results suggest that parafoveal hemodynamics, such as capillary velocity, wall shear stress, and capillary perfusion pressure can be noninvasively and reliably characterized with this method in both healthy and diabetic retinopathy patients. PMID:28078170

  20. Eye-voice span during rapid automatized naming of digits and dice in Chinese normal and dyslexic children.

    PubMed

    Pan, Jinger; Yan, Ming; Laubrock, Jochen; Shu, Hua; Kliegl, Reinhold

    2013-11-01

    We measured Chinese dyslexic and control children's eye movements during rapid automatized naming (RAN) with alphanumeric (digits) and symbolic (dice surfaces) stimuli. Both types of stimuli required identical oral responses, controlling for effects associated with speech production. Results showed that naming dice was much slower than naming digits for both groups, but group differences in eye-movement measures and in the eye-voice span (i.e. the distance between the currently fixated item and the voiced item) were generally larger in digit-RAN than in dice-RAN. In addition, dyslexics were less efficient in parafoveal processing in these RAN tasks. Since the two RAN tasks required the same phonological output and on the assumption that naming dice is less practiced than naming digits in general, the results suggest that the translation of alphanumeric visual symbols into phonological codes is less efficient in dyslexic children. The dissociation of the print-to-sound conversion and phonological representation suggests that the degree of automaticity in translation from visual symbols to phonological codes in addition to phonological processing per se is also critical to understanding dyslexia.

  1. Neural Mechanisms of Verb Argument Structure Processing in Agrammatic Aphasic and Healthy Age-Matched Listeners

    ERIC Educational Resources Information Center

    Thompson, Cynthia K.; Bonakdarpour, Borna; Fix, Stephen F.

    2010-01-01

    Processing of lexical verbs involves automatic access to argument structure entries entailed within the verb's representation. Recent neuroimaging studies with young normal listeners suggest that this involves bilateral posterior peri-sylvian tissue, with graded activation in these regions on the basis of argument structure complexity. The aim of…

  2. Pitch Characteristics Before Ulnar Collateral Ligament Reconstruction in Major League Pitchers Compared With Age-Matched Controls

    PubMed Central

    Prodromo, John; Patel, Nimit; Kumar, Neil; Denehy, Kevin; Tabb, Loni Philip; Tom, James

    2016-01-01

    Background: Ulnar collateral ligament reconstruction (UCLR) is commonly performed in Major League Baseball (MLB) pitchers, but little is known about the preoperative pitch type and velocity characteristics of pitchers who go on to undergo UCLR. Hypothesis: Pitchers who required UCLR have thrown a greater percentage of fastballs and have greater pitch velocities compared with age-matched controls in the season before injury. Study Design: Case-control study; Level of evidence, 3. Methods: MLB pitchers active during the 2002 to 2015 seasons were included. The UCLR group consisted of MLB pitchers who received UCLR between 2003 and 2015, utilizing the season before surgery (2002-2014) for analysis. The control group comprised age-matched controls of the same season. Players who pitched less than 20 innings in the season before surgery were excluded. Pitch types were recorded as percentage of total pitches thrown. Pitch velocities were recorded for each pitch type. Pitch type and pitch velocities during preoperative seasons for UCLR pitchers were compared with age-matched controls using univariate and multivariate models. Results: A total of 114 cases that went on to UCLR and 3780 controls were included in the study. Pitchers who went on to UCLR appear to have greater fastball, slider, curveball, changeup, and split-fingered fastball velocities; there were no significant differences in pitch selection between the 2 groups. Conclusion: In the season before surgery, MLB pitchers who underwent UCLR demonstrated greater fastball, slider, curveball, changeup, and split-fingered fastball velocities, with no significant difference in pitch type. PMID:27350954

  3. Automated determination of cup-to-disc ratio for classification of glaucomatous and normal eyes on stereo retinal fundus images

    NASA Astrophysics Data System (ADS)

    Muramatsu, Chisako; Nakagawa, Toshiaki; Sawada, Akira; Hatanaka, Yuji; Yamamoto, Tetsuya; Fujita, Hiroshi

    2011-09-01

    Early diagnosis of glaucoma, which is the second leading cause of blindness in the world, can halt or slow the progression of the disease. We propose an automated method for analyzing the optic disc and measuring the cup-to-disc ratio (CDR) on stereo retinal fundus images to improve ophthalmologists' diagnostic efficiency and potentially reduce the variation on the CDR measurement. The method was developed using 80 retinal fundus image pairs, including 25 glaucomatous, and 55 nonglaucomatous eyes, obtained at our institution. A disc region was segmented using the active contour method with the brightness and edge information. The segmentation of a cup region was performed using a depth map of the optic disc, which was reconstructed on the basis of the stereo disparity. The CDRs were measured and compared with those determined using the manual segmentation results by an expert ophthalmologist. The method was applied to a new database which consisted of 98 stereo image pairs including 60 and 30 pairs with and without signs of glaucoma, respectively. Using the CDRs, an area under the receiver operating characteristic curve of 0.90 was obtained for classification of the glaucomatous and nonglaucomatous eyes. The result indicates potential usefulness of the automated determination of CDRs for the diagnosis of glaucoma.

  4. Associations Between Physical Fitness Indices and Working Memory in Breast Cancer Survivors and Age-Matched Controls

    PubMed Central

    Mackenzie, Michael J.; Zuniga, Krystle E.; Raine, Lauren B.; Awick, Elizabeth A.; Hillman, Charles H.; Kramer, Arthur F.

    2016-01-01

    Abstract Background: This study examined the effects of cardiorespiratory fitness, heart rate recovery, and physical activity on working memory in breast cancer survivors and age-matched controls. Method: Using a case-control design, 32 women who had received a breast cancer diagnosis and completed primary treatment within the past 36-months (11 radiation only; 21 chemotherapy) and 30 age-matched women with no previous cancer diagnosis completed a n-back continuous performance task commonly used as an assessment of working memory. In addition, cardiorespiratory fitness and heart rate recovery were measured during a submaximal graded exercise test and physical activity was measured using 7-days of accelerometer monitoring. Results: Breast cancer survivors who had received chemotherapy had poorer heart rate recovery (p = .010) and engaged in less physical activity than women who had received radiation only (p = .004) or non-cancer controls (p = .029). Cancer treatment (radiation; chemotherapy) predicted differences in reaction times on the 1-back working memory task (p = .029). However, more rapid heart rate recovery predicted shorter reaction times on the 1-back task in the age-matched control group (p = .002). All participants with greater cardiorespiratory fitness displayed greater accuracy independent of disease status on the 1-back task (p = .017). No significant group differences in reaction times were observed for 2-back target trials between breast cancer survivors and controls. However, greater total physical activity predicted shorter reaction times in breast cancer survivors (radiation, chemotherapy) on the 2-back task (p = .014). In addition, all participants who exhibited more rapid heart rate recovery demonstrated better greater accuracy regardless of disease status (p = .013). Conclusion: These findings support differences in physical activty participation, heart rate recovery, and 1- and 2-back working memory reaction

  5. Effect of Light Scattering and Higher-order Aberrations on Visual Performance in Eyes with Granular Corneal Dystrophy.

    PubMed

    Kamiya, Kazutaka; Kobashi, Hidenaga; Igarashi, Akihito; Shoji, Nobuyuki; Shimizu, Kimiya

    2016-04-18

    This study was aimed to assess the relationship of intraocular forward scattering, corneal backward scattering, and corneal higher-order aberrations (HOAs) with corrected distance visual acuity (CDVA) in eyes with granular corneal dystrophy (GCD). We retrospectively examined forty two eyes of 42 consecutive patients who diagnosed GCD, and age-matched 20 eyes of 20 healthy subjects. We assessed objective scattering index (OSI) using the double-pass instrument (OQAS II, Visiometrics), corneal densitometry (CD) using the Scheimpflug rotating camera (Pentacam HR, Oculus), and corneal HOAs using the Hartmann-Shack aberrometry (KR-9000, Topcon). The OSI, CD, and corneal HOAs were significantly larger in the GCD group than those in the control group (Mann-Whitney U test, p < 0.001). We found significant correlations of logMAR CDVA with the OSI (Spearman correlation coefficient r = 0.577, p < 0.001), and with the CD (r = 0.340, p = 0.028), but no significant association with corneal HOAs (r = 0.061, p = 0.701). Intraocular forward scattering, corneal backward scattering, and corneal HOAs in eyes with GCD were higher than that in normal eyes. The CDVA was significantly correlated with intraocular forward scattering, but not with corneal HOAs in eyes with GCD, suggesting that light scattering, especially forward scattering, plays a more vital role in visual performance than corneal aberrations in eyes with GCD.

  6. Are the prevalence and treatment of asthma similar in elite athletes and the aged-matched non-athlete population?

    PubMed

    Locke, S; Marks, G

    2007-12-01

    The objective of this study was to determine the prevalence of asthma and use of asthma medications in elite athletes compared with an age-matched non-athlete population. Data were collected from the respiratory component of annual medical screening of 424 elite athletes from the Queensland Academy of Sport. Measures included the prevalence of current asthma and ever doctor-diagnosed asthma, and the prevalence of use of treatment for asthma including beta-agonists and inhaled corticosteroid medication. The prevalence of current asthma in athletes aged 18-29 years was 14% (95% CI, 9-19%), which did not differ significantly from the prevalence in the non-athlete control population (11%; 95% CI, 9-12%, P=0.3). Of athletes with current asthma, 27% were not taking any medications for asthma, and 25% were treated with short-acting beta-agonist medications alone and were not taking inhaled corticosteroids. These data indicate that the overall cumulative and period prevalence of asthma in Queensland athletes is similar to that in the general age-matched population. Athletes use beta-agonists with a frequency similar to the general population.

  7. Eye Cancer

    MedlinePlus

    ... Cancer > Eye Cancer > Eye Cancer: Overview Request Permissions Eye Cancer: Overview Approved by the Cancer.Net Editorial ... trained to treat intraocular cancer. Parts of the eye The eye is the organ that collects light ...

  8. Eye redness

    MedlinePlus

    Bloodshot eyes; Red eyes; Scleral injection; Conjunctival injection ... There are many causes of a red eye or eyes. Some are medical emergencies. Others are a cause for concern, but not an emergency. Many are nothing to worry about. Eye ...

  9. Rod-like microglia are restricted to eyes with laser-induced ocular hypertension but absent from the microglial changes in the contralateral untreated eye.

    PubMed

    de Hoz, Rosa; Gallego, Beatriz I; Ramírez, Ana I; Rojas, Blanca; Salazar, Juan J; Valiente-Soriano, Francisco J; Avilés-Trigueros, Marcelino; Villegas-Perez, Maria P; Vidal-Sanz, Manuel; Triviño, Alberto; Ramírez, José M

    2013-01-01

    In the mouse model of unilateral laser-induced ocular hypertension (OHT) the microglia in both the treated and the normotensive untreated contralateral eye have morphological signs of activation and up-regulation of MHC-II expression in comparison with naïve. In the brain, rod-like microglia align to less-injured neurons in an effort to limit damage. We investigate whether: i) microglial activation is secondary to laser injury or to a higher IOP and; ii) the presence of rod-like microglia is related to OHT. Three groups of mice were used: age-matched control (naïve, n=15); and two lasered: limbal (OHT, n=15); and non-draining portion of the sclera (scleral, n=3). In the lasered animals, treated eyes as well as contralateral eyes were analysed. Retinal whole-mounts were immunostained with antibodies against, Iba-1, NF-200, MHC-II, CD86, CD68 and Ym1. In the scleral group (normal ocular pressure) no microglial signs of activation were found. Similarly to naïve eyes, OHT-eyes and their contralateral eyes had ramified microglia in the nerve-fibre layer related to the blood vessel. However, only eyes with OHT had rod-like microglia that aligned end-to-end, coupling to form trains of multiple cells running parallel to axons in the retinal surface. Rod-like microglia were CD68+ and were related to retinal ganglion cells (RGCs) showing signs of degeneration (NF-200+RGCs). Although MHC-II expression was up-regulated in the microglia of the NFL both in OHT-eyes and their contralateral eyes, no expression of CD86 and Ym1 was detected in ramified or in rod-like microglia. After 15 days of unilateral lasering of the limbal and the non-draining portion of the sclera, activated microglia was restricted to OHT-eyes and their contralateral eyes. However, rod-like microglia were restricted to eyes with OHT and degenerated NF-200+RGCs and were absent from their contralateral eyes. Thus, rod-like microglia seem be related to the neurodegeneration associated with HTO.

  10. Prematurely delivered rats show improved motor coordination during sensory-evoked motor responses compared to age-matched controls.

    PubMed

    Roberto, Megan E; Brumley, Michele R

    2014-05-10

    The amount of postnatal experience for perinatal rats was manipulated by delivering pups one day early (postconception day 21; PC21) by cesarean delivery and comparing their motor behavior to age-matched controls on PC22 (the typical day of birth). On PC22, pups were tested on multiple measures of motor coordination: leg extension response (LER), facial wiping, contact righting, and fore- and hindlimb stepping. The LER and facial wiping provided measures of synchronous hind- and forelimb coordination, respectively, and were sensory-evoked. Contact righting also was sensory-evoked and provided a measure of axial coordination. Stepping provided a measure of alternated forelimb and hindlimb coordination and was induced with the serotonin receptor agonist quipazine. Pups that were delivered prematurely and spent an additional day in the postnatal environment showed more bilateral limb coordination during expression of the LER and facial wiping, as well as a more mature righting strategy, compared to controls. These findings suggest that experience around the time of birth shapes motor coordination and the expression of species-typical behavior in the developing rat.

  11. Eye Movements in Alzheimer’s Disease

    PubMed Central

    Molitor, Robert J.; Ko, Philip C.; Ally, Brandon A.

    2015-01-01

    A growing body of literature has investigated changes in eye movements as a result of Alzheimer’s disease (AD). When compared to healthy, age-matched controls, patients display a number of remarkable alterations to oculomotor function and viewing behavior. In this article, we review AD-related changes to fundamental eye movements, such as saccades and smooth pursuit motion, in addition to changes to eye movement patterns during more complex tasks like visual search and scene exploration. We discuss the cognitive mechanisms that underlie these changes and consider the clinical significance of eye movement behavior, with a focus on eye movements in mild cognitive impairment. We conclude with directions for future research. PMID:25182738

  12. Eye-tracking in amyotrophic lateral sclerosis: A longitudinal study of saccadic and cognitive tasks.

    PubMed

    Proudfoot, Malcolm; Menke, Ricarda A L; Sharma, Rakesh; Berna, Claire M; Hicks, Stephen L; Kennard, Christopher; Talbot, Kevin; Turner, Martin R

    2015-01-01

    A relative preservation of eye movements is notable in ALS, but saccadic functions have not been studied longitudinally. ALS overlaps with FTD, typically involving executive dysfunction, and eye-tracking offers additional potential for the assessment of extramotor pathology where writing and speaking are both impaired. Eye-tracking measures (including anti-saccade, trail-making and visual search tasks) were assessed at six-monthly intervals for up to two years in a group of ALS (n = 61) and primary lateral sclerosis (n = 7) patients, compared to healthy age-matched controls (n = 39) assessed on a single occasion. Task performance was explored speculatively in relation to resting-state functional MRI (R-FMRI) network connectivity. Results showed that ALS patients were impaired on executive and visual search tasks despite normal basic saccadic function, and impairments in the PLS patients were unexpectedly often more severe. No significant progression was detected longitudinally in either group. No changes in R-FMRI network connectivity were identified in relation to patient performance. In conclusion, eye-tracking offers an objective means to assess extramotor cerebral involvement in ALS. The relative resistance of pure oculomotor function is confirmed, and higher-level executive impairments do not follow the same rate of decline as physical disability. PLS patients may have more cortical dysfunction than has been previously appreciated.

  13. Eye-tracking in amyotrophic lateral sclerosis: A longitudinal study of saccadic and cognitive tasks

    PubMed Central

    Proudfoot, Malcolm; Menke, Ricarda A.L.; Sharma, Rakesh; Berna, Claire M.; Hicks, Stephen L.; Kennard, Christopher; Talbot, Kevin; Turner, Martin R.

    2016-01-01

    A relative preservation of eye movements is notable in ALS, but saccadic functions have not been studied longitudinally. ALS overlaps with FTD, typically involving executive dysfunction, and eye-tracking offers additional potential for the assessment of extramotor pathology where writing and speaking are both impaired. Eye-tracking measures (including anti-saccade, trail-making and visual search tasks) were assessed at six-monthly intervals for up to two years in a group of ALS (n = 61) and primary lateral sclerosis (n = 7) patients, compared to healthy age-matched controls (n = 39) assessed on a single occasion. Task performance was explored speculatively in relation to resting-state functional MRI (R-FMRI) network connectivity. Results showed that ALS patients were impaired on executive and visual search tasks despite normal basic saccadic function, and impairments in the PLS patients were unexpectedly often more severe. No significant progression was detected longitudinally in either group. No changes in R-FMRI network connectivity were identified in relation to patient performance. In conclusion, eye-tracking offers an objective means to assess extramotor cerebral involvement in ALS. The relative resistance of pure oculomotor function is confirmed, and higher-level executive impairments do not follow the same rate of decline as physical disability. PLS patients may have more cortical dysfunction than has been previously appreciated. PMID:26312652

  14. Eye pain

    MedlinePlus

    Ophthalmalgia; Pain - eye ... Pain in the eye can be an important symptom of a health problem. Make sure you tell your health care provider if you have eye pain that does not go away. Tired eyes or ...

  15. Healthy Eyes

    MedlinePlus

    ... of this page please turn Javascript on. Healthy Eyes Maintaining Your Vision Click for more information Taking ... have a comprehensive dilated eye exam. Who Performs Eye Exams? An eye care professional is either an ...

  16. Preserved Learning during the Symbol–Digit Substitution Test in Patients with Schizophrenia, Age-Matched Controls, and Elderly

    PubMed Central

    Cornelis, Claudia; De Picker, Livia J.; Hulstijn, Wouter; Dumont, Glenn; Timmers, Maarten; Janssens, Luc; Sabbe, Bernard G. C.; Morrens, Manuel

    2015-01-01

    Objective: Speed of processing, one of the main cognitive deficits in schizophrenia is most frequently measured with a digit–symbol-coding test. Performance on this test is additionally affected by writing speed and the rate at which symbol–digit relationships are learned, two factors that may be impaired in schizophrenia. This study aims to investigate the effects of sensorimotor speed, short-term learning, and long-term learning on task performance in schizophrenia. In addition, the study aims to explore differences in learning effects between patients with schizophrenia and elderly individuals. Methods: Patients with schizophrenia (N = 30) were compared with age-matched healthy controls (N = 30) and healthy elderly volunteers (N = 30) during the Symbol–Digit Substitution Test (SDST). The task was administered on a digitizing tablet, allowing precise measurements of the time taken to write each digit (writing time) and the time to decode symbols into their corresponding digits (matching time). The SDST was administered on three separate days (day 1, day 2, day 7). Symbol–digit repetitions during the task represented short-term learning and repeating the task on different days represented long-term learning. Results: The repetition of the same symbol–digit combinations within one test and the repetition of the test over days resulted in significant decreases in matching time. Interestingly, these short-term and long-term learning effects were about equal among the three groups. Individual participants showed a large variation in the rate of short-term learning. In general, patients with schizophrenia had the longest matching time whereas the elderly had the longest writing time. Writing time remained the same over repeated testing. Conclusion: The rate of learning and sensorimotor speed was found to have a substantial influence on the SDST score. However, a large individual variation in learning rate should be taken into account in the

  17. Which oropharyngeal factors are significant risk factors for obstructive sleep apnea? An age-matched study and dentist perspectives

    PubMed Central

    Ruangsri, Supanigar; Jorns, Teekayu Plangkoon; Puasiri, Subin; Luecha, Thitisan; Chaithap, Chariya; Sawanyawisuth, Kittisak

    2016-01-01

    Objective Obstructive sleep apnea (OSA) is a common sleep breathing disorder. Untreated OSA may lead to a number of cardiovascular complications. Dentists may play an important role in OSA detection by conducting careful oral examinations. This study focused on the correlation of oral anatomical features in Thai patients who presented with OSA. Methods We conducted a prospective comparative study at a sleep/hypertension clinic and a dental clinic at Khon Kaen University in Thailand. Patients with OSA were enrolled in the study, along with age-matched patients with non-OSA (controls). Baseline characteristics, clinical data, and oropharyngeal data of all patients were compared between the two groups. Oropharyngeal measurements included tongue size, torus mandibularis, Mallampati classification, palatal space, and lateral pharyngeal wall area. Multivariate logistic regression analysis was used to identify the factors associated with OSA. Results During the study period, there were 156 patients who met the study criteria; 78 were patients with OSA and the other 78 were healthy control subjects. In the OSA group, there were 43 males with a mean age of 53 (standard deviation 12.29) years and a mean BMI of 30.86 kg/mm2. There were 37 males in the control group with a mean age of 50 (standard deviation 12.04) years and a mean BMI of 24.03 kg/mm2. According to multivariate logistic analysis, three factors were perfectly associated with OSA, including torus mandibularis class 6, narrow lateral pharyngeal wall, and Mallampati class 4. There were two other significant factors associated with having OSA, namely, BMI and Mallampati classification. The adjusted odds ratios (95% confidence interval) of these two factors were 1.445 (1.017, 2.052) and 5.040 (1.655, 15.358), respectively. Conclusion Dentists may play an important role in the detection of OSA in patients with high BMI through careful oropharyngeal examination in routine dental treatment. A large torus mandibularis

  18. 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 ...

  19. Eye Injuries

    MedlinePlus

    The structure of your face helps protect your eyes from injury. Still, injuries can damage your eye, sometimes severely enough that you could lose your vision. Most eye injuries are preventable. If you play sports or ...

  20. Eye Cancer

    MedlinePlus

    Cancer of the eye is uncommon. It can affect the outer parts of the eye, such as the eyelid, which are made up ... adults are melanoma and lymphoma. The most common eye cancer in children is retinoblastoma, which starts in ...

  1. Watery eyes

    MedlinePlus

    ... the most common causes of excess tearing is dry eyes . Drying causes the eyes to become uncomfortable, which stimulates the body to produce too many tears. One of the main tests for tearing is to check whether the eyes ...

  2. Dry eye disease in patients with metabolic syndrome

    PubMed Central

    Cabuk, Kubra Serefoglu; Cakir, Ilkay; Kirgiz, Ahmet; Atalay, Kursat; Taskapili, Muhittin

    2016-01-01

    Objectives To evaluate dry eye disease (DED) in patients with metabolic syndrome (MetS) and compare with healthy individuals. Methods The study was conducted in the Ophthalmology and Endocrinology Department of Bagcilar Education and Research Hospital, a tertiary care center in Istanbul, Turkey, between January and December 2015. In this prospective case-controlled study, dry eye disease tests were performed on 44 patients with MetS and 43 healthy controls. TearLab Osmolarity System, which is a lab-on-a-chip technology, was used to measure tear osmolarity. McMonnies & Ho symptoms questionnaire along with Schirmer I test and tear film break-up time (TFBUT) test were also performed. Statistical evaluation was performed by students’ independent test. Results There was no statistically significant difference in tear osmolarity, TFBUT, and McMonnies & Ho questionnaire scores between MetS and normal group. However, Schirmer I test was significantly higher in MetS group (14.8±9.4mm versus 20.4±9.4, p=0.007). In women subgroup, tear osmolarity was significantly higher in MetS group compared to the normal group and over the cut-off score 308 mOsm/L (309.4±13.1 mOsm/L versus 301.2±8.7mOsm/L, p=0.012). Conclusion Patients with MetS present with lower tear volumes and a higher incidence of lacrimal gland hypofunction than age-matched controls. Especially women with MetS have higher tear osmolarities, which disrupt the normal functioning of the ocular surface and cause inflammation. Clinicians should be aware of higher DED incidence in patients with MetS for early treatment to prevent serious ocular complications. PMID:27874148

  3. A 14-year-old girl who regained normal vision after bilateral visual impairment following hot water injury to the eyes

    PubMed Central

    Monsudi, Kehinde F.; Ayanniyi, Abdulkabir A.

    2010-01-01

    A 14-year-old girl presented with bilateral visual impairment following hot water injury to the eyes. The patient was admitted for a week and managed with guttae tropicamide 0.5% 8 h, diclofenac sodium 0.1% 4 h, and fluoroquinolone 0.3% 6 h and ointment chloramphenicol 8 h. Also, the patient was managed with capsule doxycycline 100 mg 12 h for 10 days, tablet cataflam 50 mg 12 h for 7 days and intramuscular tetanus toxoid 0.5 mg stat and dermacine cream for facial scald. The visual acuities improved from 3/60 (right eye) and 6/24 (left eye) to 6/6 in both eyes. There were resolutions of facial/eye pain, tearing, photophobia, lid edema, blepharospasm, and conjunctival hyperemia. There was complete healing of facial wounds and corneal ulcers. She was discharged from hospital on the 7th day of admission. Prompt presentation, degree of scald sustained, and appropriate medical intervention enhanced visual recovery and wound healing in the patient. PMID:23960925

  4. Eye movement tics.

    PubMed Central

    Shawkat, F; Harris, C M; Jacobs, M; Taylor, D; Brett, E M

    1992-01-01

    An 8-year-old girl presented with opsoclonus-like eye movement and an 18 month history of intermittent facial tics. Investigations were all normal. Electro-oculography showed the eye movements to be of variable amplitude (10-40 degrees), with no intersaccadic interval, and with a frequency of 3-4 Hz. Saccades, smooth pursuit, optokinetic, and vestibular reflexes were all normal. These abnormal eye movements eventually disappeared. It is thought that they were a form of ocular tics. PMID:1477052

  5. [Tear osmolarity and dry eye].

    PubMed

    Pan, Shi-yin; Xiao, Xiang-hua; Wang, Yang-zheng; Liu, Xian-ning; Zhu, Xiu-ping

    2011-05-01

    Dry eye is a common eye disease, and its incidence rate has been escalating. The increased tear osmolarity is one of the main reasons for complaint, damage and inflammation of dry eye patients. With the breakthrough of testing technology for tear osmolarity, more research and application of tear osmolarity was reported, and papers on tear osmolarity of normal eye and dry eye in different regions were also published. In this article, the progress of the tear osmolarity research, the range of tear osmolarity and its application in diagnosis and therapy of dry eye was introduced, and the prospect for the clinical application of hypotonic artificial tears was also discussed.

  6. Impact of Limiting Visual Input on Gait: Individuals with Parkinson Disease, Age-matched Controls and Healthy Young Participants

    PubMed Central

    Pilgram, Laura M.; Earhart, Gammon M.; Pickett, Kristen A.

    2016-01-01

    Normal and limited vision gait was investigated in individuals with Parkinson disease (PD), healthy older and healthy young individuals. Participants walked a GAITRite mat with normal vision or vision of lower limbs occluded. Results indicate individuals with PD walked more slowly, with shorter and wider steps and spent more time in double support with limited vision as compared to full vision. Healthy young and old individuals took shorter steps but were otherwise unchanged between conditions. PMID:26987577

  7. Eye rubbing-induced changes in intraocular pressure and corneal thickness measured at five locations, in subjects with ocular allergy

    PubMed Central

    Osuagwu, Uchechukwu L.; Alanazi, Saud A.

    2015-01-01

    AIM To assess the effects of eye rubbing on corneal thickness (CT) and intraocular pressure (IOP) measurements obtained 0-30min after habitual eye rubbing in symptomatic patients. METHODS Measurements of IOP and CT were obtained at five locations (central, temporal, superior, nasal and inferior) before, and every 5min for 30min interval after 30s of eye rubbing, for 25 randomly selected eyes of 14 subjects with ocular allergy and 11 age-matched normals. Differences in measurements were calculated in each group [Baseline measurements minus measurements recorded at each time interval after eye rubbing (for IOP), and for each corneal location (for CT)] and comparison were then made between groups (allergic versus control) for differences in any observed effects. RESULTS Within groups, baseline mean IOPs in the allergic patient-group (14.2±3.0 mm Hg) and in the control group (13.1±1.9 mm Hg) were similar at all times, after eye rubbing (P >0.05, for all). The maximum reduction in IOP was 0.8 mm Hg in the control subjects and the maximum increase was also 0.8 mm Hg in the allergic subjects. Between groups (allergic versus control), the changes in IOP remained under 1 mm Hg at all times (P=0.2) after 30min of eye rubbing. Between 0 and 30min of CT measurements after eye rubbing, the mean central CT (CCT), inferior CT (ICT), superior CT (SCT), temporal CT (TCT) and nasal CT (NCT) did not vary significantly from baseline values in the control and allergic-subject groups (P>0.05, for both). Between both groups, changes in CT were similar at all locations (P>0.05) except for the TC which was minimally thinner by about 4.4 µm (P=0.001) in the allergic subjects than in the control subjects, 30min following 30s of eye rubbing. CONCLUSION IOP measured in allergic subjects after 30s of habitual eye rubbing was comparable with that obtained in normal subjects at all times between 0 and 30min. Although, CT in the allergic subjects were similar to those of the control subjects at

  8. Theories of Spoken Word Recognition Deficits in Aphasia: Evidence from Eye-Tracking and Computational Modeling

    ERIC Educational Resources Information Center

    Mirman, Daniel; Yee, Eiling; Blumstein, Sheila E.; Magnuson, James S.

    2011-01-01

    We used eye-tracking to investigate lexical processing in aphasic participants by examining the fixation time course for rhyme (e.g., "carrot-parrot") and cohort (e.g., "beaker-beetle") competitors. Broca's aphasic participants exhibited larger rhyme competition effects than age-matched controls. A re-analysis of previously reported data (Yee,…

  9. Brief Report: Does Eye Contact Induce Contagious Yawning in Children with Autism Spectrum Disorder?

    ERIC Educational Resources Information Center

    Senju, Atsushi; Kikuchi, Yukiko; Akechi, Hironori; Hasegawa, Toshikazu; Tojo, Yoshikuni; Osanai, Hiroo

    2009-01-01

    Individuals with autism spectrum disorder (ASD) reportedly fail to show contagious yawning, but the mechanism underlying the lack of contagious yawning is still unclear. The current study examined whether instructed fixation on the eyes modulates contagious yawning in ASD. Thirty-one children with ASD, as well as 31 age-matched typically…

  10. The questionably dry eye.

    PubMed Central

    Mackie, I. A.; Seal, D. V.

    1981-01-01

    This paper is concerned with the recognition of the dry eye when the clinical diagnosis is in doubt and other external eye diseases may be present. Papillary conjunctivitis is common to the dry eye as well as other pathological conditions and confuses the diagnosis. We have correlated the factors involved in the assessment for dryness. We have shown that particulate matter in the unstained tear film is associated with low tear lysozyme concentration. Tear flow and tear lysozyme are not necessarily interrelated, but a low lysozyme concentration (tear lysozyme ratio < 1.0) is associated with keratoconjunctivitis sicca. The Schirmer I test can produce false positive results, and we have suggested a modification to overcome this. This modified test will detect the eye with severely depleted lysozyme secretion, but it is unreliable for detecting the eye with moderately depleted secretion. We find that its lowest normal limit should be considered as 6 mm. Images PMID:7448154

  11. Eye Movement Disorders in Dyslexia. Final Report.

    ERIC Educational Resources Information Center

    Festinger, Leon; And Others

    Eye movements of 18 male and seven female dyslexic children and 10 normal children were evaluated to determine if eye movement disorders may be the cause of some of the symptoms associated with dyslexia. Data on eye movements were collected while Ss moved their eyes from one fixation point to another in a nonreading situation. Errors in vertical…

  12. Abnormal Fixational Eye Movements in Amblyopia

    PubMed Central

    Shaikh, Aasef G.; Otero-Millan, Jorge; Kumar, Priyanka; Ghasia, Fatema F.

    2016-01-01

    Purpose Fixational saccades shift the foveal image to counteract visual fading related to neural adaptation. Drifts are slow eye movements between two adjacent fixational saccades. We quantified fixational saccades and asked whether their changes could be attributed to pathologic drifts seen in amblyopia, one of the most common causes of blindness in childhood. Methods Thirty-six pediatric subjects with varying severity of amblyopia and eleven healthy age-matched controls held their gaze on a visual target. Eye movements were measured with high-resolution video-oculography during fellow eye-viewing and amblyopic eye-viewing conditions. Fixational saccades and drifts were analyzed in the amblyopic and fellow eye and compared with controls. Results We found an increase in the amplitude with decreased frequency of fixational saccades in children with amblyopia. These alterations in fixational eye movements correlated with the severity of their amblyopia. There was also an increase in eye position variance during drifts in amblyopes. There was no correlation between the eye position variance or the eye velocity during ocular drifts and the amplitude of subsequent fixational saccade. Our findings suggest that abnormalities in fixational saccades in amblyopia are independent of the ocular drift. Discussion This investigation of amblyopia in pediatric age group quantitatively characterizes the fixation instability. Impaired properties of fixational saccades could be the consequence of abnormal processing and reorganization of the visual system in amblyopia. Paucity in the visual feedback during amblyopic eye-viewing condition can attribute to the increased eye position variance and drift velocity. PMID:26930079

  13. Your Eyes

    MedlinePlus

    ... the eye and keeps it healthy. previous continue Light, Lens, Action These next parts are really cool, ... the eye. previous continue Rods and Cones Process Light The retina uses special cells called rods and ...

  14. Eye emergencies

    MedlinePlus

    ... tissue covering the front of the eye. Dust, sand, and other debris can easily enter the eye. ... clear itself of tiny objects, like eyelashes and sand, through blinking and tearing. If not, don't ...

  15. Eye Emergencies

    MedlinePlus

    ... Fight for victory. Marfan & Related Disorders What is Marfan Syndrome? What are Related Disorders? What are the Signs? ... Emergencies Eye Emergencies Lung Emergencies Surgeries Eye Emergencies Marfan syndrome significantly increases your risk of retinal detachment, a ...

  16. Eye Anatomy

    MedlinePlus

    ... News About Us Donate In This Section Eye Anatomy en Español email Send this article to a ... You at Risk For Glaucoma? Childhood Glaucoma Eye Anatomy Five Common Glaucoma Tests Glaucoma Facts and Stats ...

  17. Relationship Between Visual Field Sensitivity and Retinal Nerve Fiber Layer Thickness Measured by Scanning Laser Polarimetry and Optical Coherence Tomography in Normal, Ocular Hypertensive and Glaucomatous Eyes

    PubMed Central

    Lleó-Pérez, Antonio; Ortuño-Soto, Amparo; Rahhal, M.S.; Sanchis-Gimeno, Juan A.

    2010-01-01

    Purpose To evaluate the correlation between automated achromatic perimetry (AAP) and the output of two retinal nerve fiber layer (RNFL) analysers: scanning laser polarimetry (GDx-VCC) and optical coherence tomography (OCT). Methods Quantitative RNFL measurements with GDx-VCC and Stratus-OCT were obtained in one eye from 52 healthy subjects, 38 ocular hypertensive (OHT) patients and 94 glaucomatous patients. All patients underwent a complete examination, including AAP using the Swedish interactive threshold algorithm (SITA). The relationship between RNFL measurements and SITA visual field global indices were assessed by means of the following methods: analysis of variance, bivariate Pearson's correlation coefficient, multivariate linear regression techniques and nonlinear regression models, and the coefficient of determination (r2) was calculated. Results RNFL thickness values were significantly lower in glaucomatous eyes than in healthy and ocular hypertensive eyes for both nerve fiber analysers (P≤0.001), except for the inferior 120° average thickness in GDx-VCC. Linear regression models constructed for GDx-VCC measurements and OCT-derived RNFL thickness with SITA visual field global indices demonstrated that, for the mean deviation, the only predictor in the model was the nerve fiber indicator for GDx-VCC (r2=0.255), and for the pattern standard deviation, the predictors in the model were the nerve fiber indicator for GDx-VCC (r2=0.246) and the maximum thickness in the superior quadrant for Stratus-OCT (r2=0.196). The best curvilinear fit was obtained with the cubic model. Conclusions Quantitative measurements of RNFL thickness using either GDx-VCC or OCT correlate moderately with visual field global indices in moderate glaucoma patients. We did not find a correlation between visual field global indices and RNFL thickness in early glaucoma patients. Further study is needed to develop new analytical methods that will increase RNFL analyser's sensitivity in

  18. Eye Allergies

    MedlinePlus

    ... It is usually a temporary condition associated with seasonal allergies. You can get eye allergies from pet dander, ... Privacy Policy Related Is El Niño Making Your Allergies Worse? May 16, 2016 The link between seasonal allergens and dry eye Apr 27, 2015 Eye ...

  19. Green Light-emitting Diodes Light Stimuli during Incubation Enhances Posthatch Growth without Disrupting Normal Eye Development of Broiler Embryos and Hatchlings.

    PubMed

    Zhang, L; Zhu, X D; Wang, X F; Li, J L; Gao, F; Zhou, G H

    2016-11-01

    Monochromatic green light-emitting diodes (LED) light stimuli influences the posthatch growth performance of chicks. This study was undertaken with the following objectives: i) to examine whether the green LED light stimuli induces an overheating effect by determining weight loss rate of fertile eggs during incubation period; ii) to look for the development of eyes and other primary organs at different ages of embryos and newly hatched chicks. Arbor Acres fertile broiler eggs (n = 480) were randomly assigned to 3 incubation groups and exposed to continuous white light, green light, or a dark environment (control) from the first day to 19 d of incubation. The light sourced from LED lamps with the intensity of 30 lx at eggshell level. The results showed that either green or white light stimuli during incubation did not significantly affect the weight loss rate of fertile eggs, hatching time, hatchability, chick embryo, or body weight (BW), the weight percentage of heart, liver, and eyes, as well as obvious systematic abnormalities in eye weight, side-to-side, back-to-front, or corneal diameter from 15 d of embryogenesis to 6 d of posthatch (p>0.05). Compared with the dark condition, green light stimuli during incubation tended to increase feed intake (p = 0.080), improved the BW gain of chicks during 0 to 6 day posthatch (p<0.05), and increased the percentage of pectoral muscle to the BW on 3- and 6-day-old chicks. In addition, embryos or chicks in green light had lower weight percentage of yolk retention on 19 d of embryogenesis and 1 d of posthatch in comparison to those in dark or white group (p<0.05). These results suggest that providing 30 lx green LED light stimuli during incubation has no detrimental effect on the development of eyes, heart and liver of embryos and hatchlings, but does have potential benefits in terms of enhancement of the chick growth during the early posthatch stages. In addition, the fertile broiler eggs stimulated with 30 lx green LED

  20. Comparative gait analysis between children with autism and age-matched controls: analysis with temporal-spatial and foot pressure variables.

    PubMed

    Lim, Bee-Oh; O'Sullivan, David; Choi, Bum-Gwon; Kim, Mi-Young

    2016-01-01

    [Purpose] The purpose of this study was to investigate the gait pattern of children with autism by using a gait analysis system. [Subjects] Thirty children were selected for this study: 15 with autism (age, 11.2 ± 2.8 years; weight, 48.1 ± 14.1 kg; height, 1.51 ± 0.11 m) and 15 healthy age-matched controls (age, 11.0 ± 2.9 years; weight, 43.6 ± 10 kg; height, 1.51 ± 0.011 m). [Methods] All participants walked three times on the GAITRite(®) system while their plantar pressure was being recorded. [Results] The results showed a reduction in cadence, gait velocity, and step length, and an increase in step width in children with autism. Plantar pressure variables highlight the differences between the active pressure areas, especially in the hindfoot of children with autism. [Conclusion] The results suggest that children with autism have an abnormal gait compared with that of age-matched controls, and thus they need extra attention to correct these abnormal gait patterns.

  1. 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.

  2. Experiment K-7-31: Studies of Vestibular Primary Afferents and Eye Movements in Normal, Hypergravity and Hypogravity - Axon Cosmos Flight 2044

    NASA Technical Reports Server (NTRS)

    Correia, M. J.; Perachio, A. A.; Dickman, J. D.; Kozlovskaya, I.; Sirota, M.; Yakushin, S.; Beloozerova, I. N.

    1994-01-01

    Fourteen days of active head movements in microgravity appear to modify the gain and neural adaptation properties of the horizontal semicircular canals in the rhesus monkey. This is the first demonstration of adaptive plasticity in the sensory receptor. Reversing prisms, for example, do not modify the gain of the primary afferent response. Pulse yaw rotation, sinusoidal rotation, and sum of sinusoidal rotation testing during the first day following recovery revealed that the gain of a sample of afferents was significantly greater than the gain derived from afferent responses obtained during pre-flight and control monkey testing. There was no strong evidence of tilt sensitivity in the sample of afferents that we tested either during the pre-flight or control tests or during the first day post-flight. Two irregular afferents tested on postflight day 2 showed changes with tilt but the responses were not systematic. The spontaneous discharge did not change following flight. Mean firing rate and coefficient of variation remained constant during the post flight tests and was near the value measured during pre flight tests. The change in gain of horizontal canal afferents might be adaptive. The animals were required to look at a target for food. This required active head and eye movements. Active head movements have been shown to be hypometric and eye movements have been shown to be hypermetric during the first few days of past Cosmos flights (see introduction). It might be that the increased gain in the horizontal semicircular canals permit accurate target acquisition during hypometric head movements by driving the eyes to greater angles for smaller angles of head movement. The mechanism by which the semicircular canals recalibrate (increase their gain) is unknown. The efferent vestibular system is a logical candidate. Horizontal nystagmus during rotation about an earth vertical axis with the horizontal semicircular canals in the plane of rotation produced the same

  3. Eye development.

    PubMed

    Baker, Nicholas E; Li, Ke; Quiquand, Manon; Ruggiero, Robert; Wang, Lan-Hsin

    2014-06-15

    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 article 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.

  4. The Long-Term Effect of Radical Prostatectomy on Erectile Function, Urinary Continence, and Lower Urinary Tract Symptoms: A Comparison to Age-Matched Healthy Controls

    PubMed Central

    Ponholzer, Anton; Augustin, Herbert; Madersbacher, Stephan; Pummer, Karl

    2017-01-01

    Introduction. To analyze the impact of radical prostatectomy (RPE) on erectile function and lower urinary tract function in comparison to age-matched healthy men. Materials and Methods. Patients who underwent radical retropubic prostatectomy completed questionnaires containing the IIEF-5, the Bristol female LUTS questionnaire, and the International Prostate Symptom Score (IPSS). Results. Patients after RPE were included (n = 363). Age-matched healthy men (n = 363) were included. The mean IIEF-5 of patients aged 61–70 yrs after RPE was 10.4 ± 6.6 versus 18.8 ± 5.3 in the control cohort; the respective values for men aged 71–80 yrs after RPE were 7.2 ± 6.5 versus 13.6 ± 7.7 in the control cohort. Urinary incontinence after RPE was reported in 41.9% (61–70 years) and 37.7% (71–80) versus 7.5% and 15.1% in the control cohort. The mean IPSS of patients after RPE aged 61–70 yrs was 5.0 ± 4.4 versus 5.5 ± 4.9 in the control cohort; the respective values for men aged 71–80 yrs were 6.0 ± 4.9 versus 7.5 ± 5.7 in the healthy cohort. Conclusions. The negative effect of radical prostatectomy on erectile and urinary incontinence remains substantial. The physiologically declining erectile and lower urinary tract function with ageing reduces the difference between healthy men and those after surgery. Healthy men have a higher IPSS presumably due to the presence of bladder outlet obstruction. PMID:28261619

  5. Exercise performance and cardiovascular health variables in 70-year-old male soccer players compared to endurance-trained, strength-trained and untrained age-matched men.

    PubMed

    Randers, Morten Bredsgaard; Andersen, Jesper L; Petersen, Jesper; Sundstrup, Emil; Jakobsen, Markus D; Bangsbo, Jens; Saltin, Bengt; Krustrup, Peter

    2014-01-01

    The aim was to investigate performance variables and indicators of cardiovascular health profile in elderly soccer players (SP, n = 11) compared to endurance-trained (ET, n = 8), strength-trained (ST, n = 7) and untrained (UT, n = 7) age-matched men. The 33 men aged 65-85 years underwent a testing protocol including measurements of cycle performance, maximal oxygen uptake (VO2max) and body composition, and muscle fibre types and capillarisation were determined from m. vastus lateralis biopsy. In SP, time to exhaustion was longer (16.3 ± 2.0 min; P < 0.01) than in UT (+48%) and ST (+41%), but similar to ET (+1%). Fat percentage was lower (P < 0.05) in SP (-6.5% points) than UT but not ET and ST. Heart rate reserve was higher (P < 0.05) in SP (104 ± 16 bpm) than UT (+21 bpm) and ST (+24 bpm), but similar to ET (+2 bpm), whereas VO2max was not significantly different in SP (30.2 ± 4.9 ml O2 · min(-1) · kg(-1)) compared to UT (+14%) and ST (+9%), but lower (P < 0.05) than ET (-22%). The number of capillaries per fibre was higher (P < 0.05) in SP than UT (53%) and ST (42%) but similar to ET. SP had less type IIx fibres than UT (-12% points). In conclusion, the exercise performance and cardiovascular health profile are markedly better for lifelong trained SP than for age-matched UT controls. Incremental exercise capacity and muscle aerobic capacity of SP are also superior to lifelong ST athletes and comparable to endurance athletes.

  6. Diabetes eye exams

    MedlinePlus

    Diabetic retinopathy - eye exams; Diabetes - eye exams; Glaucoma - diabetic eye exam; Macular edema - diabetic eye exam ... if the doctor who takes care of your diabetes checks your eyes, you need an eye exam ...

  7. Fluorescein eye stain

    MedlinePlus

    ... Blinking spreads the dye and coats the tear film covering the surface of the cornea. The tear film contains water, oil, and mucus to protect and ... is normal, the dye remains in the tear film on the surface of the eye and does ...

  8. The connective tissue and glial framework in the optic nerve head of the normal human eye: light and scanning electron microscopic studies.

    PubMed

    Oyama, Tokuhide; Abe, Haruki; Ushiki, Tatsuo

    2006-12-01

    The arrangement of connective tissue components (i.e., collagen, reticular, and elastic fibers) and glial elements in the optic nerve head of the human eye was investigated by the combined use of light microscopy and scanning electron microscopy (SEM). Light-microscopically, the optic nerve head could be subdivided into four parts from the different arrangements of the connective tissue framework: a surface nerve fiber layer, and prelaminar, laminar, and postlaminar regions. The surface nerve fiber layer only possessed connective tissue elements around blood vessels. In the prelaminar region, collagen fibrils, together with delicate elastic fibers, formed thin interrupted sheaths for accommodating small nerve bundles. Immunohistochemistry for the glial fibrillary acidic protein (GFAP) showed that GFAP-positive cells formed columnar structures (i.e., glial columns), with round cell bodies piled up into layers. These glial columns were located in the fibrous sheaths of collagen fibrils and elastic fibers. In the laminar region, collagen fibrils and elastic fibers ran transversely to the optic nerve axis to form a thick membranous layer - the lamina cribrosa - which had numerous round openings for accommodating optic nerve fiber bundles. GFAP-positive cellular processes also ran transversely in association with collagen and elastin components. The postlaminar region had connective tissues which linked the lamina cribrosa with fibrous sheaths for accommodating nerve bundles in the extraocular optic nerve, where GFAP-positive cells acquired characteristics typical of fibrous astrocytes. These findings indicate that collagen fibrils, as a whole, form a continuous network which serves as a skeletal framework of the optic nerve head for protecting optic nerve fibers from mechanical stress as well as for sustaining blood vessels in the optic nerve. The lamina cribrosa containing elastic fibers are considered to be plastic against the mechanical force affected by elevation

  9. Eye Health

    PubMed Central

    Connell, A. M. S.

    1988-01-01

    The status of eye care in the Caribbean is discussed. Methods of primary eye care providers at all levels from primary to tertiary in the region are presented against a background of the major causes of blindness, cataract, glaucoma, and diabetic retinopathy. Epidemiological surveys examining prevalence, risk factors, and intervention programs are being undertaken. PMID:3404562

  10. Eye Infections

    MedlinePlus

    ... Issues Listen Español Text Size Email Print Share Eye Infections in Infants & Children Page Content ​​​If the ... must be treated early to prevent serious complications. Eye infections that occur after the newborn period: These ...

  11. Your Eyes

    MedlinePlus

    ... sense combinations of light waves that enable our eyes to see millions of colors. Helping You See It All Rods and cones ... the great messenger in the back of your eye. The rods and cones of the retina change the colors and shapes you see into millions of nerve ...

  12. Eyes - bulging

    MedlinePlus

    ... emotional support is important. When to Contact a Medical Professional Call your health care provider if: You have bulging eyes and the cause has not yet been diagnosed. Bulging eyes are accompanied by other symptoms. ... The provider will ask about your medical history and do a physical exam. Some questions ...

  13. Ectopic Six3 expression in the dragon eye goldfish.

    PubMed

    Ma, Dong-Mei; Zhu, Hua-Ping; Gui, Jian-Fang

    2008-02-01

    For goldfish (Carassius auratus), there are many varieties with different eye phenotypes due to artificial selection and adaptive evolution. Dragon eye is a variant eye characterized by a large-size eyeball protruding out of the socket similar to the eye of dragon in Chinese legends. In this study, anatomical structure of the goldfish dragon eye was compared with that of the common eye, and a stretching of the retina was observed in the enlarged dragon eye. Moreover, the homeobox-containing transcription factor Six3 cDNAs were cloned from the two types of goldfish, and the expression patterns were analyzed in both normal eye and dragon eye goldfish. No amino acid sequence differences were observed between the two deduced peptides, and the expression pattern of Six3 protein in dragon eye is quite similar to common eye during embryogenesis, but from 2 days after hatching, ectopic Six3 expression began to occur in the dragon eye, especially in the outer nuclear layer cells. With eye development, more predominant Six3 distribution was detected in the outer nuclear layer cells of dragon eye than that of normal eye, and fewer cell-layers in outer nuclear layer were observed in dragon eye retina than in normal eye retina. The highlight of this study is that higher Six3 expression occurs in dragon eye goldfish than in normal eye goldfish during retinal development of larvae.

  14. The Left Hand Second to Fourth Digit Ratio (2D:4D) Does Not Discriminate World-Class Female Gymnasts from Age Matched Sedentary Girls

    PubMed Central

    Peeters, Maarten W.; Claessens, Albrecht L.

    2012-01-01

    Introduction The second to fourth-digit-ratio (2D:4D), a putative marker of prenatal androgen action and a sexually dimorphic trait, has been suggested to be related with sports performance, although results are not univocal. If this relation exists, it is most likely to be detected by comparing extreme groups on the continuum of sports performance. Methods In this study the 2D:4D ratio of world-class elite female artistic gymnasts (n = 129), competing at the 1987 Rotterdam World-Championships was compared to the 2D:4D ratio of sedentary age-matched sedentary girls (n = 129), alongside with other anthropometric characteristics including other sexually dimorphic traits such as an androgyny index (Bayer & Bayley) and Heath-Carter somatotype components (endomorphy, mesomorphy, ectomorphy) using AN(C)OVA. 2D:4D was measured on X-rays of the left hand. Results Left hand 2D:4D digit ratio in world class elite female gymnasts (0.921±0.020) did not differ significantly from 2D:4D in age-matched sedentary girls (0.924±0.018), either with or without inclusion of potentially confounding covariates such as skeletal age, height, weight, somatotype components or androgyny index. Height (161.9±6.4 cm vs 155.4±6.6 cm p<0.01), weight (53.9±7.6 kg vs 46.2 6.3 kg p<0.01), BMI (20.51±2.41 kg/m2 vs 19.05±1.56 kg/m2), skeletal age (15.2±1.1 y vs 14.5±1.2 y p>0.01), somatotype components (4.0/3.0/2.9 vs 1.7/3.7/3.2 for endomorphy (p<0.01), mesomorphy (p<0.01) and ectomorphy (p<0.05) respectively) all differed significantly between sedentary girls and elite gymnasts. As expressed by the androgyny index, gymnasts have, on average, broader shoulders relative to their hips, compared to the reference sample. Correlations between the 2D:4D ratio and chronological age, skeletal age, and the anthropometric characteristics are low and not significant. Conclusion Although other anthropometric characteristics of sexual dimorphism were significantly different between the two samples

  15. Histopathology of Conjunctivochalasis Compared to Normal Conjunctiva

    PubMed Central

    Hashemian, Hesam; Mahbod, Mirgholamreza; Amoli, Fahimeh A.; Kiarudi, Mohammad Y.; Jabbarvand, Mahmoud; Kheirkhah, Ahmad

    2016-01-01

    Purpose: To evaluate the histopathologic changes in the conjunctiva of patients with conjunctivochalasis (CCh) compared to age-matched controls. Methods: This cross-sectional, controlled study included 27 eyes of 27 patients with CCh and 16 eyes of 16 age-matched controls. A biopsy of the bulbar conjunctiva was performed along the temporal lower lid margin before cataract surgery in both groups. Histopathologic evaluation of the specimens was done with light microscopy using staining with hematoxylin/eosin, periodic acid Schiff, and van Gieson elastic stain. Various histopathologic features of the conjunctival epithelium and stroma were compared between the two groups. Results: The mean age of patients was 62.4 ± 6.9 years in the CCh group and 65.1 ± 6.3 years in the control group (P = 0.54). No significant differences were noted between the two groups in terms of conjunctival epithelial changes including papillomatosis, epithelial clefts, epithelial goblet cells, or infiltration of inflammatory cells. Mean thickness of the conjunctival stroma was 0.21 ± 0.08 mm in the CCh group and 0.26 ± 0.21 mm in the control group (P = 0.10). For the conjunctival stroma, there were no significant differences between the two groups in terms of elastosis, fibrosis, lymphangiectasia, or infiltration of inflammatory cells. Conclusion: No noticeable differences were found in the histopathologic features by light microscopy between eyes with CCh and those of age-matched controls. Therefore, the primary pathology of CCh may not be within the conjunctiva itself. Instead, loose attachment of the conjunctiva to the underlying tissue may be the reason for the redundant folds in the bulbar conjunctiva. PMID:27994801

  16. Black Eye

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  17. Eye Symptoms

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  18. Dry Eye

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  19. Healthy Eyes

    MedlinePlus

    ... openings visit HHS USAJobs Home > Healthy Eyes Healthy Vision Diabetes Diabetes Home How Much Do You Know? ... seeing your best. Read more. What are common vision problems? Some of the most common vision problems ...

  20. Confirming the cognition of rising scores: Fox and Mitchum (2013) predicts violations of measurement invariance in series completion between age-matched cohorts.

    PubMed

    Fox, Mark C; Mitchum, Ainsley L

    2014-01-01

    The trend of rising scores on intelligence tests raises important questions about the comparability of variation within and between time periods. Descriptions of the processes that mediate selection of item responses provide meaningful psychological criteria upon which to base such comparisons. In a recent paper, Fox and Mitchum presented and tested a cognitive theory of rising scores on analogical and inductive reasoning tests that is specific enough to make novel predictions about cohort differences in patterns of item responses for tests such as the Raven's Matrices. In this paper we extend the same proposal in two important ways by (1) testing it against a dataset that enables the effects of cohort to be isolated from those of age, and (2) applying it to two other inductive reasoning tests that exhibit large Flynn effects: Letter Series and Word Series. Following specification and testing of a confirmatory item response model, predicted violations of measurement invariance are observed between two age-matched cohorts that are separated by only 20 years, as members of the later cohort are found to map objects at higher levels of abstraction than members of the earlier cohort who possess the same overall level of ability. Results have implications for the Flynn effect and cognitive aging while underscoring the value of establishing psychological criteria for equating members of distinct groups who achieve the same scores.

  1. Influence of BMI on health-related quality of life: comparison between an obese adult cohort and age-matched population norms.

    PubMed

    Anandacoomarasamy, Ananthila; Caterson, Ian D; Leibman, Steven; Smith, Garett S; Sambrook, Phillip N; Fransen, Marlene; March, Lyn M

    2009-11-01

    The aim of this study was to determine health-related quality of life and fatigue measures in obese subjects and to compare scores with age- and gender-matched population norms. A total of 163 obese subjects were recruited from laparoscopic-adjustable gastric banding or exercise and diet weight loss programs between March 2006 and December 2007. All subjects completed the Medical Outcomes Study Short Form 36 (SF-36), Assessment of Quality of Life (AQoL), and Multidimensional Assessment of Fatigue (MAF) questionnaires. One-sample t-tests were used to compare transformed scores with age- and gender-matched population norms and controls. Obese subjects have significantly lower SF-36 physical and emotional component scores, significantly lower AQoL utility scores and significantly higher fatigue scores compared to age-matched population norms. Within the study cohort, the SF-36 physical functioning, role physical and bodily pain scores, and AQoL utility index were even lower in subjects with clinical knee osteoarthritis (OA). However, obese individuals without OA still had significantly lower scores compared to population norms. Obesity is associated with impaired health-related quality of life and disability as measured by the SF-36, AQoL, and fatigue score (MAF) compared to matched population norms.

  2. The fears, phobias and anxieties of children with autism spectrum disorders and Down syndrome: comparisons with developmentally and chronologically age matched children.

    PubMed

    Evans, David W; Canavera, Kristin; Kleinpeter, F Lee; Maccubbin, Elise; Taga, Ken

    2005-01-01

    This study compared the fears and behavior problems of 25 children with an autism spectrum disorder (ASD), 43 children with Down syndrome (DS), 45 mental age (MA) matched children, and 37 chronologically age (CA) matched children. Children's fears, phobias, anxieties and behavioral problems were assessed using parent reports. Significant differences emerged across the diagnostic groups on a variety of fears. Children with ASD were reported to have more situation phobias and medical fears, but fewer fears of harm/injury compared to all other groups. The groups also differed in terms of the pattern of correlations between fears, phobias, anxieties and behavior problems. For children with ASD, fears, phobias and anxieties were closely related to problem behaviors, whereas fears, phobias, and anxieties were less related to behavioral symptoms for the other groups of subjects. Such findings suggest that children with ASD exhibit a distinct profile of fear and anxiety compared to other mental age and chronologically age-matched children, and these fears are related to the symptoms associated with ASD.

  3. Preventing Eye Injuries

    MedlinePlus

    ... Stories Español Eye Health / Eye Health A-Z Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Infographic Five Steps to Safer Champagne Celebrations Preventing Eye Injuries Reviewed by: Brenda Pagan-Duran MD Mar. ...

  4. Stable Schizophrenia Patients Learn Equally Well as Age-Matched Controls and Better than Elderly Controls in Two Sensorimotor Rotary Pursuit Tasks

    PubMed Central

    De Picker, Livia J.; Cornelis, Claudia; Hulstijn, Wouter; Dumont, Glenn; Fransen, Erik; Timmers, Maarten; Janssens, Luc; Morrens, Manuel; Sabbe, Bernard G. C.

    2014-01-01

    Objective: To compare sensorimotor performance and learning in stable schizophrenia patients, healthy age- and sex-matched controls and elderly controls on two variations of the rotary pursuit: circle pursuit (true motor learning) and figure pursuit (motor and sequence learning). Method: In the circle pursuit, a target circle, rotating with increasing speed along a predictable circular path on the computer screen, must be followed by a cursor controlled by a pen on a writing tablet. In the eight-trial figure pursuit, subjects learn to draw a complex figure by pursuing the target circle that moves along an invisible trajectory between and around several goals. Tasks were administered thrice (day 1, day 2, day 7) to 30 patients with stable schizophrenia (S), 30 healthy age- and sex-matched controls (C), and 30 elderly participants (>65 years; E) and recorded with a digitizing tablet and pressure-sensitive pen. The outcome measure accuracy (% of time that cursor is within the target) was used to assess performance. Results: We observed significant group differences in accuracy, both in circle and figure pursuit tasks (E < S < C, p < 0.01). Strong learning effects were found in each group. Learning curves were similar in circle pursuit but differed between groups in figure pursuit. When corrected for group differences in starting level, the learning gains over the three sessions of schizophrenia patients and age-matched controls were equal and both were larger than those of the elderly controls. Conclusion: Despite the reduced sensorimotor performance that was found in the schizophrenia patients, their sensorimotor learning seems to be preserved. The relevance of this finding for the evaluation of procedural learning in schizophrenia is discussed. The better performance and learning rate of the patients compared to the elderly controls was unexpected and deserves further study. PMID:25505425

  5. Eye and orbit ultrasound

    MedlinePlus

    Echography - eye orbit; Ultrasound - eye orbit; Ocular ultrasonography; Orbital ultrasonography ... ophthalmology department of a hospital or clinic. Your eye is numbed with medicine (anesthetic drops). The ultrasound ...

  6. Harvesting clues from genome wide transcriptome analysis for exploring thalidomide mediated anomalies in eye development of chick embryo: Nitric oxide rectifies the thalidomide mediated anomalies by swinging back the system to normal transcriptome pattern.

    PubMed

    Kumar, Pavitra; Kasiviswanathan, Dharanibalan; Sundaresan, Lakshmikirupa; Kathirvel, Priyadarshan; Veeriah, Vimal; Dutta, Priya; Sankaranarayanan, Kavitha; Gupta, Ravi; Chatterjee, Suvro

    2016-02-01

    Thalidomide, the notorious teratogen is known to cause various developmental abnormalities, among which a range of eye deformations are very common. From the clinical point of view, it is necessary to pinpoint the mechanisms of teratogens that tune the gene expression. However, to our knowledge, the molecular basis of eye deformities under thalidomide treatmenthas not been reported so far. Present study focuses on the possible mechanism by which thalidomide affects eye development and the role of Nitric Oxide in recovering thalidomide-mediated anomalies of eye development using chick embryo and zebrafish models with transcriptome analysis. Transcriptome analysis showed that 403 genes were up-regulated and 223 genes were down-regulated significantly in thalidomide pre-treated embryos. 8% of the significantly modulated genes have been implicated in eye development including Pax6, OTX2, Dkk1 and Shh. A wide range of biological process and molecular function was affected by thalidomide exposure. Biological Processes including structural constituent of eye lens and Molecular functions such as visual perception and retinal metabolic process formed strong annotation clustersindicating the adverse effects of thalidomide on eye development and function. Here, we have discussed the whole embryo transcriptome with the expression of PAX6, SOX2, and CRYAAgenes from developing eyes. Our experimental data showing structural and functional aspects includingeye size, lens transparency and optic nerve activity and bioinformatics analyses of transcriptome suggest that NO could partially protect thalidomide treated embryos from its devastating effects on eye development and function.

  7. Transcriptome analysis of the planarian eye identifies ovo as a specific regulator of eye regeneration.

    PubMed

    Lapan, Sylvain W; Reddien, Peter W

    2012-08-30

    Among the millions of invertebrate species with visual systems, the genetic basis of eye development and function is well understood only in Drosophila melanogaster. We describe an eye transcriptome for the planarian Schmidtea mediterranea. Planarian photoreceptors expressed orthologs of genes required for phototransduction and microvillus structure in Drosophila and vertebrates, and optic pigment cells expressed solute transporters and melanin synthesis enzymes similar to those active in the vertebrate retinal pigment epithelium. Orthologs of several planarian eye genes, such as bestrophin-1 and Usher syndrome genes, cause eye defects in mammals when perturbed and were not previously described to have roles in invertebrate eyes. Five previously undescribed planarian eye transcription factors were required for normal eye formation during head regeneration. In particular, a conserved, transcription-factor-encoding ovo gene was expressed from the earliest stages of eye regeneration and was required for regeneration of all cell types of the eye.

  8. Pursuit Eye Movements

    NASA Technical Reports Server (NTRS)

    Krauzlis, Rich; Stone, Leland; Null, Cynthia H. (Technical Monitor)

    1998-01-01

    When viewing objects, primates use a combination of saccadic and pursuit eye movements to stabilize the retinal image of the object of regard within the high-acuity region near the fovea. Although these movements involve widespread regions of the nervous system, they mix seamlessly in normal behavior. Saccades are discrete movements that quickly direct the eyes toward a visual target, thereby translating the image of the target from an eccentric retinal location to the fovea. In contrast, pursuit is a continuous movement that slowly rotates the eyes to compensate for the motion of the visual target, minimizing the blur that can compromise visual acuity. While other mammalian species can generate smooth optokinetic eye movements - which track the motion of the entire visual surround - only primates can smoothly pursue a single small element within a complex visual scene, regardless of the motion elsewhere on the retina. This ability likely reflects the greater ability of primates to segment the visual scene, to identify individual visual objects, and to select a target of interest.

  9. Do the eyes scan dream images during rapid eye movement sleep? Evidence from the rapid eye movement sleep behaviour disorder model.

    PubMed

    Leclair-Visonneau, Laurène; Oudiette, Delphine; Gaymard, Bertrand; Leu-Semenescu, Smaranda; Arnulf, Isabelle

    2010-06-01

    to normal rapid eye movement sleep.

  10. Eye Complications in IBD

    MedlinePlus

    ... Home > Resources > Eye Complications in IBD Go Back Eye Complications in IBD Email Print + Share Approximately 10% ... doctor’s attention sooner rather than later. TYPES OF EYE DISORDERS UVEITIS One of the most common eye ...

  11. Eye Injuries at Work

    MedlinePlus

    ... Ophthalmologist Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Numbers — Infographic Five Steps to Safer Champagne Celebrations Eye Injuries at Work Edited by: Shirley Dang Feb. ...

  12. Conjunctivitis (Pink Eye)

    MedlinePlus

    ... can be embedded on web pages. Conjunctivitis (Pink Eye) One-Page Overview Pink, itchy eyes? Conjunctivitis – or ... yourself from getting and spreading pink eye . Pink Eye: What To Do Discusses causes and treatment, when ...

  13. Conjunctivitis or pink eye

    MedlinePlus

    Inflammation - conjunctiva; Pink eye; Chemical conjunctivitis, Pinkeye; Pink-eye ... Tears most often protect the eyes by washing away the germs and irritants. Tears contain proteins and antibodies that kill germs. Pink eye is most often caused ...

  14. Eye Injuries at Home

    MedlinePlus

    ... Ophthalmologist Patient Stories Español Eye Health / Tips & Prevention Eye Injuries Sections Preventing Eye Injuries Recognizing and Treating ... Numbers — Infographic Five Steps to Safer Champagne Celebrations Eye Injuries at Home Reviewed by: Brenda Pagan-Duran ...

  15. Eye Involvement in TSC

    MedlinePlus

    ... Privacy Policy Sitemap Learn Engage Donate About TSC Eyes Campbell (1905) first described the eye involvement in ... some form of eye involvement. Nonretinal and Retinal Eye Findings Facial angiofibromas may involve the eyelids of ...

  16. Eye Movement Disorders

    MedlinePlus

    ... t work properly. There are many kinds of eye movement disorders. Two common ones are Strabismus - a disorder ... of the eyes, sometimes called "dancing eyes" Some eye movement disorders are present at birth. Others develop over ...

  17. Eye muscle repair - discharge

    MedlinePlus

    ... Lazy eye repair - discharge; Strabismus repair - discharge; Extraocular muscle surgery - discharge ... You or your child had eye muscle repair surgery to correct eye muscle ... term for crossed eyes is strabismus. Children most often ...

  18. Why Do Eyes Water?

    MedlinePlus

    ... Happens in the Operating Room? Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? A ... out of your nose. continue Why Do Eyes Water? Eyes water for lots of different reasons besides ...

  19. About the Eye

    MedlinePlus

    ... NEI for Kids > About the Eye All About Vision About the Eye Ask a Scientist Video Series ... Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun ...

  20. Sports and Your Eyes

    MedlinePlus

    ... for Kids > Sports and Your Eyes All About Vision About the Eye Ask a Scientist Video Series ... Eye Health and Safety First Aid Tips Healthy Vision Tips Protective Eyewear Sports and Your Eyes Fun ...

  1. Strabismus and eye muscle function.

    PubMed

    Lennerstrand, Gunnar

    2007-11-01

    Studies of external eye muscle morphology and physiology are reviewed, with respect to both motor and sensory functions in concomitant strabismus. The eye muscles have a more complex fibre composition than other striated muscle, and they are among the fastest and most fatigue-resistant muscles in the body. However, it is not generally believed that concomitant strabismus is due to a primary abnormality of the eye muscles or the ocular motor system. The gross anatomy of eye muscles, including the shape and position of the eye muscle pulleys, was not changed in strabismus. The histology of the eye muscle fibres was also basically the same, but changes have been observed in the cellular and biochemical machinery of the fibres, most notably in the singly innervated orbital fibres. Functionally, this was seen as slower contractions and reduced fatigue resistance of eye muscles in animals with strabismus and defects of binocular vision. Most likely the changes represented an adaptation to modified visual demands on the ocular motor control, because of the defects of binocular vision in strabismus from an early age. Adaptation of eye muscle function to visual demands could be seen also in the adult human ocular motor system, but here the effects could be reversed with treatment in some conditions. External eye muscles in the human have sensory organs, muscle spindles and tendon organs, responding to changes in muscle force and length. It is not known how these proprioceptors are used more specifically in ocular motor control, and there is no stretch reflex in the external eye muscles. However, a clear influence on space localization and eye position can be demonstrated with vibratory stimulation of the eye muscles, presumably activating muscle spindles. Different effects were observed in normal subjects and in adult patients with strabismus, which would indicate that the proprioceptive input from one eye of strabismic patients could be suppressed by the other eye, similar

  2. Eye contricks

    PubMed Central

    Wade, Nicholas J

    2011-01-01

    Pictorial images are icons as well as eye-cons: they provide distillations of objects or ideas into simpler shapes. They create the impression of representing that which cannot be presented. Even at the level of the photograph, the links between icon and object are tenuous. The dimensions of depth and motion are missing from icons, and these alone introduce all manner of potential ambiguities. The history of art can be considered as exploring the missing link between icon and object. Eye-cons can also be illusions—tricks of vision so that what is seen does not necessarily correspond to what is physically presented. Pictorial images can be spatialised or stylised; spatialised images generally share some of the projective characteristics of the object represented. Written words are also icons, but they do not resemble the objects they represent—they are stylised or conventional. Icons as stylised words and spatialised images were set in delightful opposition by René Magritte in a series of pipe paintings, and this theme is here alluded to. Most of visual science is now concerned with icons—two-dimensional displays on computer monitors. Is vision now the science of eye-cons? PMID:23145240

  3. Differential gene expression in liver and small intestine from lactating rats compared to age-matched virgin controls detects increased mRNA of cholesterol biosynthetic genes

    PubMed Central

    2011-01-01

    Background Lactation increases energy demands four- to five-fold, leading to a two- to three-fold increase in food consumption, requiring a proportional adjustment in the ability of the lactating dam to absorb nutrients and to synthesize critical biomolecules, such as cholesterol, to meet the dietary needs of both the offspring and the dam. The size and hydrophobicity of the bile acid pool increases during lactation, implying an increased absorption and disposition of lipids, sterols, nutrients, and xenobiotics. In order to investigate changes at the transcriptomics level, we utilized an exon array and calculated expression levels to investigate changes in gene expression in the liver, duodenum, jejunum, and ileum of lactating dams when compared against age-matched virgin controls. Results A two-way mixed models ANOVA was applied to detect differentially expressed genes. Significance calls were defined as a p < 0.05 for the overall physiologic state effect (lactation vs. control), and a within tissue pairwise comparison of p < 0.01. The proportion of false positives, an estimate of the ratio of false positives in the list of differentially expressed genes, was calculated for each tissue. The number of differentially expressed genes was 420 in the liver, 337 in the duodenum, 402 in the jejunum, and 523 in the ileum. The list of differentially expressed genes was in turn analyzed by Ingenuity Pathways Analysis (IPA) to detect biological pathways that were overrepresented. In all tissues, sterol regulatory element binding protein (Srebp)-regulated genes involved in cholesterol synthesis showed increased mRNA expression, with the fewest changes detected in the jejunum. We detected increased Scap mRNA in the liver only, suggesting an explanation for the difference in response to lactation between the liver and small intestine. Expression of Cyp7a1, which catalyzes the rate limiting step in the bile acid biosynthetic pathway, was also significantly increased in liver. In

  4. Training understanding of reversible sentences: a study comparing language-impaired children with age-matched and grammar-matched controls.

    PubMed

    Hsu, Hsinjen Julie; Bishop, Dorothy V M

    2014-01-01

    Introduction. Many children with specific language impairment (SLI) have problems with language comprehension, and little is known about how to remediate these. We focused here on errors in interpreting sentences such as "the ball is above the cup", where the spatial configuration depends on word order. We asked whether comprehension of such short reversible sentences could be improved by computerized training, and whether learning by children with SLI resembled that of younger, typically-developing children. Methods. We trained 28 children with SLI aged 6-11 years, 28 typically-developing children aged from 4 to 7 years who were matched to the SLI group for raw scores on a test of receptive grammar, and 20 typically-developing children who were matched to the SLI group on chronological age. A further 20 children with SLI were given pre- and post-test assessments, but did not undergo training. Those in the trained groups were given training on four days using a computer game adopting an errorless learning procedure, during which they had to select pictures to correspond to spoken sentences such as "the cup is above the drum" or "the bird is below the hat". Half the trained children heard sentences using above/below and the other half heard sentences using before/after (with a spatial interpretation). A total of 96 sentences was presented over four sessions. Half the sentences were unique, whereas the remainder consisted of 12 repetitions of each of four sentences that became increasingly familiar as training proceeded. Results. Age-matched control children performed near ceiling (≥ 90% correct) in the first session and were excluded from the analysis. Around half the trained SLI children also performed this well. Training effects were examined in 15 SLI and 16 grammar-matched children who scored less than 90% correct on the initial training session. Overall, children's scores improved with training. Memory span was a significant predictor of improvement, even

  5. Imaging systems of human eye: a review.

    PubMed

    Acharya, Rajendra U; Yun, Wong Li; Ng, E Y K; Yu, Wenwei; Suri, Jasjit S

    2008-08-01

    The eyes are complex sensory organs and are designed to optimize vision under conditions of varying light. There are a number of eye disorders that can influence vision. Eye disorders among the elderly are a major health problem. With advancing age, the normal function of eye tissues decreases and there is an increased incidence of ocular pathology. The most common causes of age related eye disorder and visual impairment in the elderly are cataracts and primary open angle glaucoma. Different imaging systems are available to visualize the different parts of the eye non-invasively with higher accuracy. This paper discusses the various techniques available namely, computed tomography, confocal laser scanning microscopy, magnetic resonance imaging, optical coherence tomography, ultrasound imaging, infrared thermography for the imaging of the different eye abnormalities.

  6. Effects of Corneal Nerve Density on the Response to Treatment in Dry Eye Disease

    PubMed Central

    Kheirkhah, Ahmad; Dohlman, Thomas H; Amparo, Francisco; Arnoldner, Michael A; Jamali, Arsia; Hamrah, Pedram; Dana, Reza

    2015-01-01

    Purpose To evaluate whether levels of corneal subbasal nerve fiber length (SNFL) in dry eye disease (DED) could prognosticate the level of improvement in signs and symptoms after treatment. Design Phase IV, double-masked, randomized clinical trial. Participants Sixty patients with meibomian gland dysfunction-associated DED and 27 age-matched controls. Methods Patients with DED were randomized to receive topical artificial tears, loteprednol etabonate 0.5%, or loteprednol etabonate 0.5%/tobramycin 0.3% twice daily for 4 weeks. At baseline, in vivo confocal microscopy of central cornea was performed in both eyes. Patients with DED were divided into 2 subgroups, those with low baseline SNFL and those with near-normal baseline SNFL (the cut-off point: mean SNFL in controls minus 2 standard deviations). Clinical signs and symptoms at baseline and after 4 weeks of treatment were compared between the subgroups with low and near-normal SNFL for all therapeutic groups. Main Outcome Measures Symptom questionnaires, corneal fluorescein staining (CFS), conjunctival staining with lissamine green, tear break-up time, Schirmer’s test, and SNFL. Results In patients with DED, baseline SNFL (17.06 ± 5.78 mm/mm2) was significantly lower than in controls (23.68 ± 3.42, P=0.001). In the artificial tear and loteprednol groups, although no significant improvement in any sign or symptom was noted in patients with low baseline SNFL (<16.84 mm/mm2), subjects with near-normal baseline SNFL (≥16.84 mm/mm2) showed significant improvement in both symptoms and corneal fluorescein staining (CFS) score (all P<0.05). In the loteprednol/tobramycin group, no significant change was evident for any sign or symptom in either subgroup of low or near-normal baseline SNFL. Conclusions Significant improvements in CFS and patient symptomatology after DED treatment were evident only in the subgroup with near-normal corneal SNFL. Consideration of SNFL may thus assist in explaining the variability of

  7. Brief report: does eye contact induce contagious yawning in children with autism spectrum disorder?

    PubMed

    Senju, Atsushi; Kikuchi, Yukiko; Akechi, Hironori; Hasegawa, Toshikazu; Tojo, Yoshikuni; Osanai, Hiroo

    2009-11-01

    Individuals with autism spectrum disorder (ASD) reportedly fail to show contagious yawning, but the mechanism underlying the lack of contagious yawning is still unclear. The current study examined whether instructed fixation on the eyes modulates contagious yawning in ASD. Thirty-one children with ASD, as well as 31 age-matched typically developing (TD) children, observed video clips of either yawning or control mouth movements. Participants were instructed to fixate to the eyes of the face stimuli. Following instructed fixation on the eyes, both TD children and children with ASD yawned equally frequently in response to yawning stimuli. Current results suggest that contagious yawning could occur in ASD under an experimental condition in which they are instructed to fixate on the yawning eyes.

  8. Contrast Sensitivity in Microtropic and Anisometropic Eyes of Successfully Treated Amblyopes

    PubMed Central

    Öner, Özlem; Akça Bayar, Sezin; Oto, Sibel; Gökmen, Onur; Tekindal, Mustafa Agah

    2017-01-01

    Objectives: To assess and compare contrast sensitivity function in the previously amblyopic and non-amblyopic “normal” eyes of patients with microtropia and anisometropia who achieved 20/20 visual acuity after occlusion therapy. Materials and Methods: Contrast sensitivity was tested monocularly on both eyes of 34 successfully treated microtropic and 15 anisometropic subjects (visual acuity 20/20 in both eyes). Contrast sensitivity function was evaluated by CSV-1000E and age-matched nomograms were used (spatial frequencies of 3, 6, 12, and 18 cycles per degree [cpd]) for comparison. Results: The mean age of subjects was 11.2±1.3 years in the microtropic group, 9.8±1.7 years in the anisometropic group (7-12 years); the mean follow-up time was 16.4±3.2 months (12 to 92) in the microtropic group and 27.7±1.8 months (12-84) in the anisometropic group. Statistical comparison of the microtropic amblyopic eyes versus non-microtropic eyes showed significant differences at spatial frequencies of 3, 12 and 18 cpd (3 cpd, t=2.8, p=0.007; 6 cpd, t=1.1 p=0.261; 12 cpd, t=2.2, p=0.033; 18 cpd, t=2.2, p=0.030). When anisometropic eyes were compared with non-anisometropic eyes, there was a significant difference only at 12 cpd (t=2.1 p=0.049). The comparison of non-amblyopic eyes versus age-matched nomograms revealed no differences at any of the spatial frequencies (p>0.05 for all). Conclusion: Contrast sensitivity was decreased in patients with amblyopia, especially in the microtropic group. The assessment of contrast sensitivity function may serve as a new parameter for termination of occlusion therapy.

  9. Development of infrared thermal imager for dry eye diagnosis

    NASA Astrophysics Data System (ADS)

    Chiang, Huihua Kenny; Chen, Chih Yen; Cheng, Hung You; Chen, Ko-Hua; Chang, David O.

    2006-08-01

    This study aims at the development of non-contact dry eye diagnosis based on an infrared thermal imager system, which was used to measure the cooling of the ocular surface temperature of normal and dry eye patients. A total of 108 subjects were measured, including 26 normal and 82 dry eye patients. We have observed that the dry eye patients have a fast cooling of the ocular surface temperature than the normal control group. We have developed a simplified algorithm for calculating the temperature decay constant of the ocular surface for discriminating between normal and dry eye. This study shows the diagnostic of dry eye syndrome by the infrared thermal imager system has reached a sensitivity of 79.3%, a specificity of 75%, and the area under the ROC curve 0.841. The infrared thermal imager system has a great potential to be developed for dry eye screening with the advantages of non-contact, fast, and convenient implementation.

  10. Twisted story of eye migration in flatfish.

    PubMed

    Saele, Oystein; Smáradóttir, Heiddís; Pittman, Karin

    2006-06-01

    Early molecular markers for flatfish metamorphosis and eye migration must be linked to the ethmoid region, the earliest part of the flatfish cranium to change, as well as chondral and dermal ossification processes. Serial sections, morphological landmarks, and stereology were used to determine where and when the remodeling of tissues and asymmetry occurs in the head region of metamorphosing Atlantic halibut, Hippoglossus hippoglossus. Not all parts of the head remodel or migrate, and those that do may be asynchronous. Normal metamorphosis limits the torsion of the Atlantic halibut head to the anterior part of the neurocranium and excludes the tip of the snout and the general jaw area. The first cranial structure displaying eye migration-related asymmetric development is the paraethmoid part of the ethmoid cartilage. In early eye migration the medial frontal process moves apace with the eyes, whereas near completion the migrating eye moves significantly closer to the frontal process. Structures of the jaw remain mostly symmetrical, with the exception of the adductor mandibulae muscle and the bone maxillare, which are larger on the abocular than on the ocular side, the muscle occupying the space vacated by the migration of the eye. Thus, normal eye migration involves a series of temperospatially linked events. In juveniles lacking eye migration (arrested metamorphosis), the dermal bone, the prefrontal, does not develop. The two abnormal paraethmoids develop symmetrically as two plate-like structures curving anteriorly, whereas normal elongate fused paraethmoids curve at their posterior. The abocular side retrorbital vesicles are largest in volume only after the completion of normal eye migration. Factors involved in completion of normal metamorphosis and eye migration in flatfish affect chondral and dermal ossification signals in the ethmoid group, as well as remodeling of the mineralized frontal, a series of linked events not involving the entire neurocranium.

  11. Molecular genetic analysis of Drosophila eyes absent mutants reveals an eye enhancer element.

    PubMed Central

    Zimmerman, J E; Bui, Q T; Liu, H; Bonini, N M

    2000-01-01

    The eyes absent (eya) gene is critical for normal eye development in Drosophila and is highly conserved to vertebrates. To define regions of the gene critical for eye function, we have defined the mutations in the four viable eya alleles. Two of these mutations are eye specific and undergo transvection with other mutations in the gene. These were found to be deletion mutations that remove regulatory sequence critical for eye cell expression of the gene. Two other viable alleles cause a reduced eye phenotype and affect the function of the gene in additional tissues, such as the ocelli. These mutations were found to be insertion mutations of different transposable elements within the 5' UTR of the transcript. Detailed analysis of one of these revealed that the transposable element has become subject to regulation by eye enhancer sequences of the eya gene, disrupting normal expression of EYA in the eye. More extended analysis of the deletion region in the eye-specific alleles indicated that the deleted region defines an enhancer that activates gene expression in eye progenitor cells. This enhancer is responsive to ectopic expression of the eyeless gene. This analysis has defined a critical regulatory region required for proper eye expression of the eya gene. PMID:10628984

  12. National Eye Institute

    MedlinePlus

    ... around the world. Learn more Video: Next-Generation Eye Imaging Tools Learn about how the NEI Audacious ... eyeGENE® International Research 3-D Retina Organoid Challenge Eye and Vision Research The latest on NEI research. ...

  13. Eye Injuries (For Parents)

    MedlinePlus

    ... Old Feeding Your 1- to 2-Year-Old Eye Injuries KidsHealth > For Parents > Eye Injuries Print A ... sand, dirt, and other foreign bodies on the eye surface) Wash your hands thoroughly before touching the ...

  14. Pink Eye (Conjunctivitis)

    MedlinePlus

    ... have allergic conjunctivitis. Preventing the spread of pink eye Practice good hygiene to control the spread of ... return to school or child care. Preventing pink eye in newborns Newborns' eyes are susceptible to bacteria ...

  15. Diabetes - eye care

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000078.htm Diabetes - eye care To use the sharing features on this ... prevent them from getting worse. You Need Regular eye Exams Every year, you should have an eye ...

  16. Dilating Eye Drops

    MedlinePlus

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Dilating Eye Drops En Español Read in Chinese What are dilating eye drops? Dilating eye drops contain medication to enlarge ( ...

  17. Eye Cosmetic Safety

    MedlinePlus

    ... when they are new. FDA has an Import Alert in effect for cosmetics -- including eye cosmetics -- contaminated ... in the area of the eye. An import alert for cosmetics containing illegal colors lists several eye ...

  18. Reading Strategies of Bilingual Normally Progressing and Dyslexic Readers in Hindi and English

    ERIC Educational Resources Information Center

    Gupta, Ashum; Jamal, Gulgoona

    2007-01-01

    This study examined the reading accuracy of dyslexic readers in comparison to chronological age-matched normally progressing readers in Hindi and English using word reading tasks, matched for spoken frequency of usage, age of acquisition, imageability, and word length. Both groups showed significantly greater reading accuracy in Hindi than in…

  19. Effects of PUVA on the eye

    SciTech Connect

    Backman, H.A.

    1982-01-01

    Psoriasis is a common skin disease which may be treated with 8-methoxy psoralen and long-wave ultraviolet light (PUVA). Eye protection is provided during and after treatment to prevent the development of photokeratitis and cataracts. Fifteen patients, treated with medication and ultraviolet A (UVA) had an initial complete eye examination and a repeat examination after each treatment. No patients developed cataracts but almost one-half of the patients had a mild form of photokeratoconjunctivitis. The ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye ocular manifestations included photophobia, conjunctivitis, keratitis, and dry eyes. Tear break-up time was reduced significantly immediately after treatment for two patients but returned to normal 8 hr later. Dermatologists who employ PUVA treatments should be concerned about photokeratoconjunctivitis and the dry-eye syndrome.

  20. Eyeing Ganymede

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jupiter casts a baleful eye toward the moon Ganymede in this enhanced-contrast image from NASA's Cassini spacecraft.

    Jupiter's 'eye', the Great Red Spot, was captured just before disappearing around the eastern edge of the planet. The furrowed eyebrow above and to the left of the spot is a turbulent wake region caused by westward flow that has been deflected to the north and around the Red Spot. The smallest features visible are about 240 kilometers (150 miles) across.

    Within the band south of the Red Spot are a trio of white ovals, high pressure counterclockwise-rotating regions that are dynamically similar to the Red Spot. The dark filamentary features interspersed between white ovals are probably cyclonic circulations and, unlike the ovals, are rotating clockwise.

    Jupiter's equatorial zone stretching across the planet north of the Spot appears bright white, with gigantic plume clouds spreading out from the equator both to the northeast and to the southeast in a chevron pattern. This zone looks distinctly different than it did during the Voyager flyby 21 years ago. Then, its color was predominantly brown and the only white plumes conspicuous against the darker material beneath them were oriented southwest-to-northeast.

    Ganymede is Jupiter's largest moon, about 50 percent larger than our own Moon and larger than the planet Mercury. The visible details in this image are different geological terrains. Dark areas tend to be older and heavily cratered; brighter areas are younger and less cratered. Cassini images of Ganymede and Jupiter's other large moons taken near closest approach on Dec. 30 will have resolutions about four times better than that seen here.

    This image is a color composite of ones taken with different filters by Cassini's narrow-angle camera on Nov. 18, 2000, processed to enhance contrast. Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of

  1. Saccadic eye movement during spaceflight

    NASA Technical Reports Server (NTRS)

    Uri, John J.; Linder, Barry J.; Moore, Thomas P.; Pool, Sam L.; Thornton, William E.

    1989-01-01

    Saccadic eye movements were studied in six subjects during two Space Shuttle missions. Reaction time, peak velocity and accuracy of horizontal, visually-guided saccades were examined preflight, inflight and postflight. Conventional electro-oculography was used to record eye position, with the subjects responding to pseudo-randomly illuminated targets at 0 deg and + or - 10 deg and 20 deg visual angles. In all subjects, preflight measurements were within normal limits. Reaction time was significantly increased inflight, while peak velocity was significantly decreased. A tendency toward a greater proportion of hypometric saccades inflight was also noted. Possible explanations for these changes and possible correlations with space motion sickness are discussed.

  2. Altered aquaporin expression in glaucoma eyes.

    PubMed

    Tran, Thuy Linh; Bek, Toke; la Cour, Morten; Nielsen, Søren; Prause, Jan Ulrik; Hamann, Steffen; Heegaard, Steffen

    2014-09-01

    Aquaporins (AQP) are channels in the cell membrane that mainly facilitate a passive transport of water. In the eye, AQPs are expressed in the ciliary body and retina and may contribute to the pathogenesis of glaucoma and optic neuropathy. We investigated the expression of AQP1, AQP3, AQP4, AQP5, AQP7 and AQP9 in human glaucoma eyes compared with normal eyes. Nine glaucoma eyes were examined. Of these, three eyes were diagnosed with primary open angle glaucoma; three eyes had neovascular glaucoma; and three eyes had chronic angle-closure glaucoma. Six eyes with normal intraocular pressure and without glaucoma were used as control. Immunohistochemistry was performed using antibodies against AQP1, AQP3, AQP4, AQP5, AQP7 and AQP9. For each specimen, optical densities of immunoprecipitates were measured using Photoshop and the staining intensities were calculated. Immunostaining showed labelling of AQP7 and AQP9 in the nonpigmented ciliary epithelium and the staining intensities were significantly decreased in glaucoma eyes (p = 0.003; p = 0.018). AQP7 expression in the Müller cell endfeet was increased (p = 0.046), and AQP9 labelling of the retinal ganglion cells (RGC) showed decreased intensity (p = 0.037). No difference in AQP1, AQP4 and AQP9 expression was found in the optic nerve fibres. This study is the first investigating AQPs in human glaucoma eyes. We found a reduced expression of AQP9 in the retinal ganglion cells of glaucoma eyes. Glaucoma also induced increased AQP7 expression in the Müller cell endfeet. In the ciliary body of glaucoma eyes, the expression of AQP7 and AQP9 was reduced. Therefore, the expression of AQPs seems to play a role in glaucoma.

  3. Eating for Your Eyes

    ERIC Educational Resources Information Center

    Stastny, Sherri Nordstrom; Garden-Robinson, Julie

    2011-01-01

    An educational program targeting older adults was developed to increase knowledge regarding nutrition and eye health. With age, the chance for eye disease increases, so prevention is critical. The Eating for Your Eyes program has promoted behavior changes regarding eye health among the participants. This program is easily replicated and use is…

  4. Rapid eye movement latency in children and adolescents.

    PubMed

    Mason, Thornton B A; Teoh, Laurel; Calabro, Kristen; Traylor, Joel; Karamessinis, Laurie; Schultz, Brian; Samuel, John; Gallagher, Paul R; Marcus, Carole L

    2008-09-01

    Rapid eye movement sleep distribution changes during development, but little is known about rapid eye movement latency variation in childhood by age, sex, or pathologic sleep states. We hypothesized that: (1) rapid eye movement latency would differ in normal children by age, with a younger cohort (1-10 years) demonstrating shorter rapid eye movement latency than an older group (>10-18 years); (2) rapid eye movement latency in children would differ from typical adult rapid eye movement latency; and (3) intrinsic sleep disorders (narcolepsy, pediatric obstructive sleep apnea syndrome) would disrupt normal developmental patterns of rapid eye movement latency. A retrospective chart review included data from clinic visits and of rapid eye movement latency and other parameters measured by overnight polysomnography. Participants included 98 control children, 90 children with obstructive sleep apnea syndrome, and 13 children with narcolepsy. There were no statistically significant main effects of age category or sex on rapid eye movement latency. Rapid eye movement latency, however, exhibited a significant inverse correlation with age within the older control children. Healthy children exhibited rapid eye movement latencies significantly longer than adults. Normal control patients demonstrated significantly longer rapid eye movement latency than obstructive sleep apnea syndrome and narcolepsy patients.

  5. Eyeless initiates the expression of both sine oculis and eyes absent during Drosophila compound eye development.

    PubMed

    Halder, G; Callaerts, P; Flister, S; Walldorf, U; Kloter, U; Gehring, W J

    1998-06-01

    The Drosophila Pax-6 gene eyeless acts high up in the genetic hierarchy involved in compound eye development and can direct the formation of extra eyes in ectopic locations. Here we identify sine oculis and eyes absent as two mediators of the eye-inducing activity of eyeless. We show that eyeless induces and requires the expression of both genes independently during extra eye development. During normal eye development, eyeless is expressed earlier than and is required for the expression of sine oculis and eyes absent, but not vice versa. Based on the results presented here and those of others, we propose a model in which eyeless induces the initial expression of both sine oculis and eyes absent in the eye disc. sine oculis and eyes absent then appear to participate in a positive feedback loop that regulates the expression of all three genes. In contrast to the regulatory interactions that occur in the developing eye disc, we also show that in the embryonic head, sine oculis acts in parallel to eyeless and twin of eyeless, a second Pax-6 gene from Drosophila. Recent studies in vertebrate systems indicate that the epistatic relationships among the corresponding vertebrate homologs are very similar to those observed in Drosophila.

  6. The Effect of an Eye Movement Recorder on Head Movements,

    DTIC Science & Technology

    1982-07-01

    in several research settings. For example, the NAC Eye Mark (e Recorder system (an eye movement recorder that utilizes the cor- neal reflection...reported that the NAC system could be used with a large number of subjects and that normal eye movement patterns were not altered by the use of’ this...equipment (2,4); however, no mention has been made of the extent to which the NAC system alters normal head movement patterns. It has been shown that head

  7. The formulation of argument structure in SLI: an eye-movement study

    PubMed Central

    ANDREU, LLORENÇ; SANZ-TORRENT, MÒNICA; OLMOS, JOAN GUÀRDIA; MACWHINNEY, BRIAN

    2014-01-01

    This study investigated the formulation of verb argument structure in Catalan- and Spanish-speaking children with specific language impairment (SLI) and typically developing age-matched controls. We compared how language production can be guided by conceptual factors, such as the organization of the entities participating in an event and knowledge regarding argument structure. Eleven children with SLI (aged 3;8 to 6;6) and eleven control children participated in an eye-tracking experiment in which participants had to describe events with different argument structure in the presence of visual scenes. Picture descriptions, latency time and eye movements were recorded and analyzed. The picture description results showed that the percentage of responses in which children with SLI substituted a non-target verb for the target verb was significantly different from that for the control group. Children with SLI made more omissions of obligatory arguments, especially of themes, as the verb argument complexity increased. Moreover, when the number of arguments of the verb increased, the children took more time to begin their descriptions, but no differences between groups were found. For verb type latency, all children were significantly faster to start describing one-argument events than two- and three-argument events. No differences in latency time were found between two- and three-argument events. There were no significant differences between the groups. Eye-movement showed that children with SLI looked less at the event zone than the age-matched controls during the first two seconds. These differences between the groups were significant for three-argument verbs, and only marginally significant for one- and two-argument verbs. Children with SLI also spent significantly less time looking at the theme zones than their age-matched controls. We suggest that both processing limitations and deficits in the semantic representation of verbs may play a role in these difficulties

  8. Ageing changes in the eye

    PubMed Central

    Salvi, S M; Akhtar, S; Currie, Z

    2006-01-01

    Ageing changes occur in all the structures of the eye causing varied effects. This article attempts to review the parameters of what is considered within the “normal limits” of ageing so as to be able to distinguish those conditions from true disease processes. Improving understanding of the ageing changes will help understand some of the problems that the ageing population faces. PMID:16954455

  9. Genetic regulation of vertebrate eye development.

    PubMed

    Zagozewski, J L; Zhang, Q; Eisenstat, D D

    2014-11-01

    Eye development is a complex and highly regulated process that consists of several overlapping stages: (i) specification then splitting of the eye field from the developing forebrain; (ii) genesis and patterning of the optic vesicle; (iii) regionalization of the optic cup into neural retina and retina pigment epithelium; and (iv) specification and differentiation of all seven retinal cell types that develop from a pool of retinal progenitor cells in a precise temporal and spatial manner: retinal ganglion cells, horizontal cells, cone photoreceptors, amacrine cells, bipolar cells, rod photoreceptors and Müller glia. Genetic regulation of the stages of eye development includes both extrinsic (such as morphogens, growth factors) and intrinsic factors (primarily transcription factors of the homeobox and basic helix-loop helix families). In the following review, we will provide an overview of the stages of eye development highlighting the role of several important transcription factors in both normal developmental processes and in inherited human eye diseases.

  10. Functional eye movement disorders.

    PubMed

    Kaski, D; Bronstein, A M

    2017-01-01

    Functional (psychogenic) eye movement disorders are perhaps less established in the medical literature than other types of functional movement disorders. Patients may present with ocular symptoms (e.g., blurred vision or oscillopsia) or functional eye movements may be identified during the formal examination of the eyes in patients with other functional disorders. Convergence spasm is the most common functional eye movement disorder, but functional gaze limitation, functional eye oscillations (also termed "voluntary nystagmus"), and functional convergence paralysis may be underreported. This chapter reviews the different types of functional eye movement abnormalities and provides a practical framework for their diagnosis and management.

  11. Imaging of mouse embryonic eye development using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Syed, Saba H.; Kasiraj, Alyssa; Larina, Irina V.; Dickinson, Mary E.; Larin, Kirill V.

    2010-02-01

    Congenital abnormalities are often caused by genetic disorders which alter the normal development of the eye. Embryonic eye imaging in mouse model is important for understanding of normal and abnormal eye development and can contribute to prevention and treatment of eye defects in humans. In this study, we used Swept Source Optical Coherence Tomography (SS-OCT) to image eye structure in mouse embryos at 12.5 to 17.5 days post coitus (dpc). The imaging depth of the OCT allowed us to visualize the whole eye globe at these stages. Different ocular tissues including lens, cornea, eyelids, and hyaloid vasculature were visualized. These results suggest that OCT imaging is a useful tool to study embryonic eye development in the mouse model.

  12. Eye Movements of Flatfish for Different Gravity Condition

    NASA Astrophysics Data System (ADS)

    Iwata, Kaori; Takabayashi, Akira; Imada, Hideki; Miyachi, Ei-Ichi

    On Earth, gravity sensation plays a basic role for all of physiological phenomena in every creature. In microgravity, loss of gravity input causes many functional disorders in animals and humans. During adaptation to microgravity, otolith-mediated response such as eye movements would alter. Flatfish provide a natural model for the study of adaptive changes in the vestibuloocular reflex. During metamorphosis, vestibular and oculomotor coordinate of flatfish displaced 90 degrees about the longitudinal body axis. Therefore, it is expected that microgravity induce the sensory mismatch in adult flatfish. In this study, we analyzed the eye movements of normal and otolith removed flatfish for body tilting and the eye movements of normal flatfish during microgravity produced by parabolic aircraft flight. The fish was fixed on the tilting table controlled by computer. The eye movements for body tilting along the different body axis were video-recorded. The vertical and torsional eye rotations were analyzed frame by frame. In normal flatfish, torsional eye movements were larger for head up or head down tilting than leftward or rightward tilting. On the other hand, vertical eye movements were larger for leftward or rightward tilting than head up or head down tilting. After removal of left side utlicular otolith, the vertical eye movement for 180 degrees body tilting disappeared. For the changes of gravity, vertical eye movements were observed. These results suggested that eye movements of flatfish adapted to Earth's gravity condition and sacculus and lagena might play important role for otolith-ocular eye movements.

  13. Fixations to the eyes aids in facial encoding; covertly attending to the eyes does not.

    PubMed

    Laidlaw, Kaitlin E W; Kingstone, Alan

    2017-02-01

    When looking at images of faces, people will often focus their fixations on the eyes. It has previously been demonstrated that the eyes convey important information that may improve later facial recognition. Whether this advantage requires that the eyes be fixated, or merely attended to covertly (i.e. while looking elsewhere), is unclear from previous work. While attending to the eyes covertly without fixating them may be sufficient, the act of using overt attention to fixate the eyes may improve the processing of important details used for later recognition. In the present study, participants were shown a series of faces and, in Experiment 1, asked to attend to them normally while avoiding looking at either the eyes or, as a control, the mouth (overt attentional avoidance condition); or in Experiment 2 fixate the center of the face while covertly attending to either the eyes or the mouth (covert attention condition). After the first phase, participants were asked to perform an old/new face recognition task. We demonstrate that a) when fixations to the eyes are avoided during initial viewing then subsequent face discrimination suffers, and b) covert attention to the eyes alone is insufficient to improve face discrimination performance. Together, these findings demonstrate that fixating the eyes provides an encoding advantage that is not availed by covert attention alone.

  14. Eye movements of flatfish for the changes of gravity (II).

    PubMed

    Iwata, Kaori; Takabayashi, Akira; Miyachi, Ei-ichi

    2007-07-01

    In this study, we analysed the eye movements of flatfish for body tilting and compared with that of goldfish. The fish was fixed on the tilting table controlled by computer. The eye movements for body tilting along the different body axis were video-recorded. The vertical and torsional eye rotations were analysed frame by frame. In normal flatfish, vertical eye movement of left eye to leftward tilting was larger than that to rightward tilting. For head up or head down tilting, clear vertical eye movements were observed. On the other hand, torsional eye movements showed similar characteristics as goldfish. These results suggested that sacculus and lagena were important for otolith-ocular eye movements in flatfish.

  15. Cytogenetic investigation of cat-eye syndrome.

    PubMed

    Walknowska, J; Peakman, D; Weleber, R G

    1977-10-01

    Using multiple chromosomal banding techniques, we studied a child with typical cat-eye syndrome and ocular retraction syndrome. Although the mother was was chromosomally normal, other maternal relatives showed features of the cat-eye syndrome, suggesting the basic abnormality is heritable. The abnormal chromosome in our case was most likely the product of reciprocal translocation where short arm plus centromeric chromatin from two separate acrocentric chromosomes fused together. The chromosomes involved were probably No. 22 and either Nos. 13 or 14. The basic underlying defect in cat-eye syndrome may be a heritable fragile site or some other predisposition leading to complex chromosomal interchange.

  16. Ultrasonography of the eye and orbit.

    PubMed

    Dudea, Sorin M

    2011-06-01

    Ultrasonography (US) is, quite often, the first imaging modality used in eye and orbit assessment. The indications of ophthalmic US cover a wide range of disease where direct clinical assessment is impossible or of little value. Doppler US enhances the ability to assess blood flow in the main arteries and veins. In order to take full advantage of all the possibilities US has to offer the examiner thorough knowledge of the examination technique and normal US anatomy of the eye and orbit is required. This paper reviews the basics of the examination technique and ultrasound anatomy of the eye and orbit.

  17. Distinct Biochemical Activities of Eyes absent During Drosophila Eye Development.

    PubMed

    Jin, Meng; Mardon, Graeme

    2016-03-16

    Eyes absent (Eya) is a highly conserved transcriptional coactivator and protein phosphatase that plays vital roles in multiple developmental processes from Drosophila to humans. Eya proteins contain a PST (Proline-Serine-Threonine)-rich transactivation domain, a threonine phosphatase motif (TPM), and a tyrosine protein phosphatase domain. Using a genomic rescue system, we find that the PST domain is essential for Eya activity and Dac expression, and the TPM is required for full Eya function. We also find that the threonine phosphatase activity plays only a minor role during Drosophila eye development and the primary function of the PST and TPM domains is transactivation that can be largely substituted by the heterologous activation domain VP16. Along with our previous results that the tyrosine phosphatase activity of Eya is dispensable for normal Eya function in eye formation, we demonstrate that a primary function of Eya during Drosophila eye development is as a transcriptional coactivator. Moreover, the PST/TPM and the threonine phosphatase activity are not required for in vitro interaction between retinal determination factors. Finally, this work is the first report of an Eya-Ey physical interaction. These findings are particularly important because they highlight the need for an in vivo approach that accurately dissects protein function.

  18. Eye Injuries in Sports

    MedlinePlus

    ... eye protectors. Some very-high-risk sports are boxing, wrestling and contact martial arts.What are the ... eye problems or if you have a family history of retinal problems. If so, you should be ...

  19. Eye Injuries (For Parents)

    MedlinePlus

    ... and comfortable as possible until help arrives. continue Chemical Exposure Many chemicals, even those found around the house, can damage an eye. If your child gets a chemical in the eye and you know what it ...

  20. What Is Dry Eye?

    MedlinePlus Videos and Cool Tools

    ... Kierstan Boyd Reviewed by: Brenda Pagan-Duran MD Mar. 01, 2017 Our eyes need tears to stay ... Ask an Ophthalmologist Answers Is stopping Restasis dangerous? Mar 06, 2017 Why are my eyes bloodshot when ...

  1. Diabetes and eye disease

    MedlinePlus

    ... the eye that can lead to blindness. Macular edema. Blurry vision due to fluid leaking into the ... in your retina (neovascularization) or you develop macular edema, treatment is usually needed. Eye surgery is the ...

  2. Eye muscle repair

    MedlinePlus

    ... and physical exam before the procedure Orthoptic measurements (eye movement measurements) Always tell your child's health care provider: ... D, Plummer LS, Stass-Isern M. Disorders of eye movement and alignment. In: Kliegman RM, Stanton BF, St. ...

  3. Eye Drop Tips

    MedlinePlus

    ... Involved News About Us Donate In This Section Eye Drop Tips en Español email Send this article ... the reach of children. Steps For Putting In Eye Drops: Start by tilting your head backward while ...

  4. Down Syndrome: Eye Problems

    MedlinePlus

    ... life expectancy. Do children with Down syndrome have eye problems? Individuals with Down syndrome are at increased ... When should children with Down syndrome receive an eye exam? The American Academy of Pediatrics recommends that ...

  5. Diabetic Eye Problems

    MedlinePlus

    ... too high. Over time, this can damage your eyes. The most common problem is diabetic retinopathy. It ... light-sensitive tissue at the back of your eye. You need a healthy retina to see clearly. ...

  6. Eye Safety at Home

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  7. Recommended Sports Eye Protectors

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  8. Eye Safety at Work

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  9. Bags Under Eyes

    MedlinePlus

    ... Home and lifestyle treatments may help reduce or eliminate puffy eyes. Medical and surgical treatments are available ... The following tips can help you reduce or eliminate bags under eyes: Use a cool compress. Wet ...

  10. Eyes, Bulging (Proptosis)

    MedlinePlus

    ... Article Medical Dictionary Also of Interest (Quiz) Allergic Conjunctivitis (Video) Overview of the Eyes (News) Stem Cells ... and covers the white of the eye. Allergic conjunctivitis is inflammation of the conjunctiva caused by an ...

  11. LASIK Eye Surgery

    MedlinePlus

    ... of your cornea, which could lead to inaccurate measurements and a poor surgical outcome. Your doctor will ... of your eye. Theoretically, the more detailed the measurements, the more accurate your eye doctor can be ...

  12. Diabetic Eye Disease

    MedlinePlus

    ... visit HHS USAJobs Home > Diabetic Eye Disease Healthy Vision Diabetes Diabetes Home How Much Do You Know? What You Should Know Protecting Against Vision Loss Staying on TRACK Diabetic Eye Disease FAQ ...

  13. Infrared Eye: Prototype 2

    DTIC Science & Technology

    2016-06-07

    The Infrared (IR) Eye was developed with support from the National Search and Rescue Secretariat (NSS), in view of improving the efficiency of...airborne search-and rescue operations. The IR Eye concept is based on the human eye and uses simultaneously two fields of view to optimize area coverage and...within the wide field and slaved to the operator’s line of sight by means of an eye -tracking system. The images from both cameras are fused and shown

  14. Dwarf Eye Disorder

    ERIC Educational Resources Information Center

    Science Teacher, 2005

    2005-01-01

    Johns Hopkins researchers at the Wilmer Eye Institute have discovered what appears to be the first human gene mutation that causes extreme farsightedness. The researchers report that nanophthalmos, Greek for "dwarf eye," is a rare, potentially blinding disorder caused by an alteration in a gene called MFRP that helps control eye growth and…

  15. Eye Movements and Learning.

    ERIC Educational Resources Information Center

    Nesbit, Larry L.

    Research on the use of eye movement indices (such as number of fixations, the average fixation duration, and saccadic movements) as a measure of cognitive processing is reviewed in this paper. Information is provided on the physiology of the eye, computer applications to eye movement study, the influence of stimulus materials and intelligence on…

  16. Balance reactions and eye-hand coordination in idiopathic scoliosis.

    PubMed

    Adler, N; Bleck, E E; Rinsky, L A; Young, W

    1986-01-01

    We undertook this study to determine if subclinical postural control mechanisms were abnormal in idiopathic scoliosis. Ninety-one female patients and fifty-seven age-matched female controls were examined. We used a force plate ataxiometer to quantitate postural sway in the standing position and recorded the displacement and acceleration of the center of pressure during static stance and under perturbation with eyes opened and closed. A joystick-controlled video system was used to measure reaction time and eye-hand motor coordination. The scoliosis group demonstrated significantly less sway during two of the eight standing balance conditions and on the remaining balance tests there was a similar trend, albeit nonsignificant. The reaction time for the scoliosis group was also significantly slower, but the accuracy was not significantly worse. We noted no statistical differences between progressive and nonprogressive or between braced and unbraced patients. The subgroup of patients whose curves progressed despite bracing had a tendency to demonstrate greater stability on all standing tests. They also exhibited faster reaction times and less error in eye-hand coordination than other patient groups. No correlation existed between severity of curve and test performance. We found no indication of deficient balance in idiopathic scoliosis, and the tests could not predict curve progression.

  17. Gaze aversion in autistic and normal children.

    PubMed

    Richer, J M; Coss, R G

    1976-03-01

    Autistic children rarely engage in eye contact, and whilst observation suggests this is due to a specific avoidance of eye contact, some experimental studies have challenged this. In this study the effects on autistic and normal children of an adult looking at them with both eyes, with one eye covered, or apparently not looking at them (both eyes covered) were investigated. As expected, autistic children looked more at the adult with his eyes covered, and also engaged in less flight behaviour. They looked less when two eyes were exposed than one, confirming the potency of the two-eye pattern in provoking gaze aversion. Normal children engaged in much more eye contact than the autistic children, with fewer flight behaviours and stereotypies, supporting the hypothesis that autistic children are predominatly flight motivated. Other, sometimes conflicting, results of previous studies are discussed. Teachers and nurses are recommened not to make efforts to engage autistic children even in friendly eye contact as this provokes more flight behaviour.

  18. Eyes open versus eyes closed - Effect on human rotational responses

    NASA Technical Reports Server (NTRS)

    Wall, Conrad, III; Furman, Joseph M. R.

    1989-01-01

    The effect of eyelid closure on the response to rotational vestibular stimulation was assessed by evaluating 16 normal human subjects with both earth vertical axis (EVA) and earth horizontal axis (EHA) yaw rotations with either eyes closed (EC) or eyes open in the dark (EOD). Results indicated that for EVA rotation, the subjects' responses were of larger magnitude and less variable with EOD than with EC. However, for EHA rotation, responses were of larger magnitude and equally variable with EC as compared to EOD. Data also indicated that the quality of the EHA response with EC was altered because eyelid closure influenced the amount of periodic gaze. It is concluded that eyelid closure has an effect upon both canalocular and otolithocular reflexes and it is suggested that both EVA and EHA rotational testing be performed with EOD rather than with EC.

  19. Dry eye modifies the thermal and menthol responses in rat corneal primary afferent cool cells.

    PubMed

    Kurose, Masayuki; Meng, Ian D

    2013-07-01

    Dry eye syndrome is a painful condition caused by inadequate or altered tear film on the ocular surface. Primary afferent cool cells innervating the cornea regulate the ocular fluid status by increasing reflex tearing in response to evaporative cooling and hyperosmicity. It has been proposed that activation of corneal cool cells via a transient receptor potential melastatin 8 (TRPM8) channel agonist may represent a potential therapeutic intervention to treat dry eye. This study examined the effect of dry eye on the response properties of corneal cool cells and the ability of the TRPM8 agonist menthol to modify these properties. A unilateral dry eye condition was created in rats by removing the left lacrimal gland. Lacrimal gland removal reduced tears in the dry eye to 35% compared with the contralateral eye and increased the number of spontaneous blinks in the dry eye by over 300%. Extracellular single-unit recordings were performed 8-10 wk following surgery in the trigeminal ganglion of dry eye animals and age-matched controls. Responses of corneal cool cells to cooling were examined after the application of menthol (10 μM-1.0 mM) to the ocular surface. The peak frequency of discharge to cooling was higher and the cooling threshold was warmer in dry eye animals compared with controls. The dry condition also altered the neuronal sensitivity to menthol, causing desensitization to cold-evoked responses at concentrations that produced facilitation in control animals. The menthol-induced desensitization of corneal cool cells would likely result in reduced tearing, a deleterious effect in individuals with dry eye.

  20. Training the Eyes for Competition: Fighting Eyes.

    ERIC Educational Resources Information Center

    Williams, Darrell; Bradford, Vincent

    1989-01-01

    Fencers should be taught to discipline their eyes to focus on the opponent's hand. The rationale for this strategy as well as drills to develop "hand watching" skills are presented in this article. (IAH)

  1. Eye movements of patients with schizophrenia in a natural environment.

    PubMed

    Dowiasch, Stefan; Backasch, Bianca; Einhäuser, Wolfgang; Leube, Dirk; Kircher, Tilo; Bremmer, Frank

    2016-02-01

    Alterations of eye movements in schizophrenia patients have been widely described for laboratory settings. For example, gain during smooth tracking is reduced, and fixation patterns differ between patients and healthy controls. The question remains, whether such results are related to the specifics of the experimental environment, or whether they transfer to natural settings. Twenty ICD-10 diagnosed schizophrenia patients and 20 healthy age-matched controls participated in the study, each performing four different oculomotor tasks corresponding to natural everyday behavior in an indoor environment: (I) fixating stationary targets, (II) sitting in a hallway with free gaze, (III) walking down the hallway, and (IV) visually tracking a target on the floor while walking straight-ahead. In all conditions, eye movements were continuously recorded binocularly by a mobile lightweight eye tracker (EyeSeeCam). When patients looked at predefined targets, they showed more fixations with reduced durations than controls. The opposite was true when participants were sitting in a hallway with free gaze. During visual tracking, patients showed a significantly greater root-mean-square error (representing the mean deviation from optimal) of retinal target velocity. Different from previous results on smooth-pursuit eye movements obtained in laboratory settings, no such difference was found for velocity gain. Taken together, we have identified significant differences in fundamental oculomotor parameters between schizophrenia patients and healthy controls during natural behavior in a real environment. Moreover, our data provide evidence that in natural settings, patients overcome some impairments, which might be present only in laboratory studies, by as of now unknown compensatory mechanisms or strategies.

  2. Dry Eye and Designer Ophthalmics

    PubMed Central

    Laurie, Gordon W.; Olsakovsky, Leslie A.; Conway, Brian P.; McKown, Robert L.; Kitagawa, Kazuko; Nichols, Jason J.

    2009-01-01

    EST, proteomic, and antibody capture assays are revealing a level of tear film protein complexity far greater than previously appreciated. A systems biology approach will be needed to fully appreciate function as tear protein doses fluctuate in time through different conditions. Although consensus is growing on what fully constitutes the human tear proteome, questions remain about the source and significance of the ∼256 tear proteins designated as ‘intracellular’. Many of these may derive from normal cellular turnover and could therefore be informative. A further >183 are designated as ‘extracellular’. Surprisingly, only 4 – 5% of these appear to be dysregulated in the three forms of dry eye preliminarily examined to date. Some differ and a couple overlap, suggesting that disease-specific signatures could be identified. Future dry eye treatment might include recombinant tear protein rescue as a personalized ophthalmic approach to ocular surface disease. PMID:18677231

  3. Construction of special eye models for investigation of chromatic and higher-order aberrations of eyes.

    PubMed

    Zhai, Yi; Wang, Yan; Wang, Zhaoqi; Liu, Yongji; Zhang, Lin; He, Yuanqing; Chang, Shengjiang

    2014-01-01

    An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced into the eye model along visual axis. Moreover, three kinds of individual eye models are established to investigate the impacts of higher-order aberrations, chromatic aberration (LCA+TCA), LCA and TCA on vision under the photopic condition, respectively. Results show that for most human eyes, the impact of chromatic aberration on vision is much stronger than that of higher-order aberrations, and the impact of LCA in chromatic aberration dominates. The impact of TCA is approximately equal to that of normal level higher-order aberrations and it can be ignored when LCA exists.

  4. Control and Functions of Fixational Eye Movements

    PubMed Central

    Rucci, Michele; Poletti, Martina

    2016-01-01

    Humans and other species explore a visual scene by rapidly shifting their gaze 2-3 times every second. Although the eyes may appear immobile in the brief intervals in between saccades, microscopic (fixational) eye movements are always present, even when attending to a single point. These movements occur during the very periods in which visual information is acquired and processed and their functions have long been debated. Recent technical advances in controlling retinal stimulation during normal oculomotor activity have shed new light on the visual contributions of fixational eye movements and their degree of control. The emerging body of evidence, reviewed in this article, indicates that fixational eye movements are important components of the strategy by which the visual system processes fine spatial details, enabling both precise positioning of the stimulus on the retina and encoding of spatial information into the joint space-time domain. PMID:27795997

  5. Computer-Assisted Eye Examination: Background and Prospects.

    DTIC Science & Technology

    1982-05-01

    potential resolution. Squares represent normal eyes; triangles represent those with some chronic pathological process such as glaucoma, macular a...of the major generic questions are: Are you troubled in any way with blurred vision? Hlave you headaches, eye pain or eye strain, or fatigue ? Do your...cannot resolve the pattern and thus does not contribute to the response. Furthermore, the central macular area is far more extensively represented in

  6. The eyes of a tiny 'Orsten' crustacean - a compound eye at receptor level?

    PubMed

    Schoenemann, Brigitte

    2013-01-14

    Among the oldest fossil crustaceans are those of the Late Cambrian (Furongian 499 ± 0.3-488.3 ± 1.7 Ma) of Västergötland, central Sweden and the lower Ordovician (Tremadocian 488.3 and 478.6 Ma) of the island of Őland. These are three-dimensionally preserved in nodules from the so called 'stinkstone' ('Orsten') limestone. 'Orsten'-like fossils represent tiny, often meiobenthic organsisms (Haug, Maas, & Waloszek, 2009) smaller than 2mm, which mainly were arthropods, especially crustaceans close to the stemline. As a result of phosphatisation, hairs, bristles and even cellular structures up to 0.3 μm are preserved (Walossek, 1993), especially compound eyes, as typical for all visually orientated crustaceans (Schoenemann et al., 2011). We show a miniscule prototype of a compound eye (∼40 μm) in a small crustacean, which lived almost half a billion years ago. The eye is close to but comfortably established above being limited in its resolving power by diffraction, but it is too small to be an apposition eye, normally regarded as the basal form of all compound eyes, as is found in bees, dragonflies, crustaceans and many other arthropods still living today. The facets of this compound eye are ∼8 μm in size, the surface structure indicates the relicts of a tiny lens covering each facet. In order to work functionally and to ensure that that diffraction and waveguide problems were avoided, it seems reasonable to suppose that the compound eye consisted of visual units, each with a single photoreceptor cell directly below a weak lens for capturing and slightly focusing the light. The entire unit has a diameter similar to that of a normal sensory cell as found in compound eyes. Thus, the early compound eye analysed here may be interpreted as a prototype representing the earliest stages of the evolution of crustacean compound eyes.

  7. PAN-811 inhibits oxidative stress-induced cell death of human Alzheimer's disease-derived and age-matched olfactory neuroepithelial cells via suppression of intracellular reactive oxygen species.

    PubMed

    Nelson, Valery M; Dancik, Chantée M; Pan, Weiying; Jiang, Zhi-Gang; Lebowitz, Michael S; Ghanbari, Hossein A

    2009-01-01

    Oxidative stress plays a significant role in neurotoxicity associated with a variety of neurodegenerative diseases including Alzheimer's disease (AD). Increased oxidative stress has been shown to be a prominent and early feature of vulnerable neurons in AD. Olfactory neuroepithelial cells are affected at an early stage. Exposure to oxidative stress induces the accumulation of intracellular reactive oxygen species (ROS), which in turn causes cell damage in the form of protein, lipid, and DNA oxidations. Elevated ROS levels are also associated with increased deposition of amyloid-beta and formation of senile plaques, a hallmark of the AD brain. If enhanced ROS exceeds the basal level of cellular protective mechanisms, oxidative damage and cell death will result. Therefore, substances that can reduce oxidative stress are sought as potential drug candidates for treatment or preventative therapy of neurodegenerative diseases such as AD. PAN-811, also known as 3-aminopyridine-2-carboxaldehyde thiosemicarbazone or Triapine, is a small lipophilic compound that is currently being investigated in several Phase II clinical trials for cancer therapy due to its inhibition of ribonucleotide reductase activity. Here we show PAN-811 to be effective in preventing or reducing ROS accumulation and the resulting oxidative damages in both AD-derived and age-matched olfactory neuroepithelial cells.

  8. Eye development and the appearance and maintenance of corneal transparency

    NASA Technical Reports Server (NTRS)

    Conrad, G. W.; Funderburgh, J. L.; Spooner, B. S. (Principal Investigator)

    1992-01-01

    Embryonic development of the eye, including the cornea, depends on the appearance and steady maintenance of intraocular pressure. The eye is a gravity-sensitive organ, as evidence by changes in pupil diameter during parabolic flight. The cornea is largely a paracrystal of extracellular matrix. The extent to which it will polymerize normally in microgravity has yet to be determined.

  9. The Role of Eye Movements in Subitizing and Counting

    ERIC Educational Resources Information Center

    Watson, Derrick G.; Maylor, Elizabeth A.; Bruce, Lucy A. M.

    2007-01-01

    Previous work has suggested that eye movements may be necessary for accurate enumeration beyond the subitization range of about 4 items. This study determined the frequency of eye movements normally made during enumeration, their relationship to response times, and whether they are required for accurate performance. This was achieved by monitoring…

  10. The Effect of Labels Only and Labels with Instruction on the Concept Attainment of Educable Mentally Retarded and Normally Developing Boys of School Age. Technical Report No. 301.

    ERIC Educational Resources Information Center

    Gargiulo, Richard Michael

    Examined were the effects of verbal labels alone and in combination with two types of instruction on the concept attainment of 80 educable mentally retarded and 80 normal boys of school age matched for mental age. For learning the concept "equilateral triangle" Ss were randomly assigned to one of four experimental treatment conditions: verbal…

  11. Eye proprioception may provide real time eye position information.

    PubMed

    Wang, Jing; Pan, Yujun

    2013-03-01

    Because of the frequency of eye movements, online knowledge of eye position is crucial for the accurate spatial perception and behavioral navigation. Both the internal monitoring signal (corollary discharge) of eye movements and the eye proprioception signal are thought to contribute to the localization of the eye position in the orbit. However, the functional role of these two eye position signals in spatial cognition has been disputed for more than a century. The predominant view proposes that the online analysis of eye position is exclusively provided by the corollary discharge signal, while the eye proprioception signal only plays a role in the long-term calibration of the oculomotor system. However, increasing evidence from recent behavioral and physiological studies suggests that the eye proprioception signal may play a role in the online monitoring of eye position. The purpose of this review is to discuss the feasibility and possible function of the eye proprioceptive signal for online monitoring of eye position.

  12. Photorefraction of the Eye

    ERIC Educational Resources Information Center

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-01-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical…

  13. Common Eye Disorders

    MedlinePlus

    ... eye,” is the most common cause of vision impairment in children. Amblyopia is the medical term used ... the most common cause of permanent one-eye vision impairment among children and young and middle-aged adults. ...

  14. Why Do Eyes Water?

    MedlinePlus

    ... A Movies & More Quizzes Kids' Dictionary of Medical Words En Español What Other Kids Are Reading Taking Care of Your Ears Taking Care of Your Skin Taking Care of Your Teeth El cuidado de los dientes Video: Getting an X-ray Why Do Eyes Water? KidsHealth > For Kids > Why Do Eyes Water? Print ...

  15. An Eye for Learning.

    ERIC Educational Resources Information Center

    Ostwald, Thomas

    1995-01-01

    Presents a hands-on activity as an excellent starting point for investigations related to the eye. Involves making a simple model of the vertebrate eye to illustrate the formation of an upside-down image on the retina by the lens. Links to investigations in numerous science disciplines including astronomy, genetics, biology, earth science, and…

  16. Understanding pink eye

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pink eye (PE) is a physiological tuber disorder that can result in serious processing complications and storage losses. The earliest external symptoms consist of an ephemeral pinkish discoloration around tuber eyes, predominately at the bud end of the tuber. These pinkish areas can then develop into...

  17. Image Quality Analysis of Eyes Undergoing LASER Refractive Surgery

    PubMed Central

    Sarkar, Samrat; Vaddavalli, Pravin Krishna; Bharadwaj, Shrikant R.

    2016-01-01

    Laser refractive surgery for myopia increases the eye’s higher-order wavefront aberrations (HOA’s). However, little is known about the impact of such optical degradation on post-operative image quality (IQ) of these eyes. This study determined the relation between HOA’s and IQ parameters (peak IQ, dioptric focus that maximized IQ and depth of focus) derived from psychophysical (logMAR acuity) and computational (logVSOTF) through-focus curves in 45 subjects (18 to 31yrs) before and 1-month after refractive surgery and in 40 age-matched emmetropic controls. Computationally derived peak IQ and its best focus were negatively correlated with the RMS deviation of all HOA’s (HORMS) (r≥-0.5; p<0.001 for all). Computational depth of focus was positively correlated with HORMS (r≥0.55; p<0.001 for all) and negatively correlated with peak IQ (r≥-0.8; p<0.001 for all). All IQ parameters related to logMAR acuity were poorly correlated with HORMS (r≤|0.16|; p>0.16 for all). Increase in HOA’s after refractive surgery is therefore associated with a decline in peak IQ and a persistence of this sub-standard IQ over a larger dioptric range, vis-à-vis, before surgery and in age-matched controls. This optical deterioration however does not appear to significantly alter psychophysical IQ, suggesting minimal impact of refractive surgery on the subject’s ability to resolve spatial details and their tolerance to blur. PMID:26859302

  18. Computer Analysis of Eye Blood-Vessel Images

    NASA Technical Reports Server (NTRS)

    Wall, R. J.; White, B. S.

    1984-01-01

    Technique rapidly diagnoses diabetes mellitus. Photographs of "whites" of patients' eyes scanned by computerized image analyzer programmed to quantify density of small blood vessels in conjuctiva. Comparison with data base of known normal and diabetic patients facilitates rapid diagnosis.

  19. Are 3-D Movies Bad for Your Eyes?

    MedlinePlus

    ... the viewer has a problem with focusing or depth perception. Also, the techniques used to create the 3- ... eyes), or other conditions that persistently inhibit focusing, depth perception or normal 3-D vision, would have difficulty ...

  20. How Were Eye Movements Recorded Before Yarbus?

    PubMed

    Wade, Nicholas J

    2015-01-01

    Alfred Yarbus introduced a new dimension of precision in recording how the eyes moved, either when attempts were made to keep them stationary or when scanning pictures. Movements of the eyes had been remarked upon for millennia, but recording how they move is a more recent preoccupation. Emphasis was initially placed on abnormalities of oculomotor function (like strabismus) before normal features were considered. The interest was in where the eyes moved to rather than determining how they got there. The most venerable technique for examining ocular stability involved comparing the relative motion between an afterimage and a real image. In the late 18th century, Wells compared afterimages generated before body rotation with real images observed following it when dizzy; he described both lateral and torsional nystagmus, thereby demonstrating the directional discontinuities in eye velocities. At around the same time Erasmus Darwin used afterimages as a means of demonstrating ocular instability when attempting to fixate steadily. However, the overriding concern in the 19th century was with eye position rather than eye movements. Thus, the characteristics of nystagmus were recorded before those of saccades and fixations. Eye movements during reading were described by Hering and by Lamare (working in Javal's laboratory) in 1879; both used similar techniques of listening (with tubes placed over the eyelids) to the 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. Eye movements over pictures were examined by Stratton and later by Buswell, who drew attention to the effects of instructions on the pattern of eye movements. In midcentury, attention shifted back to the stability of the eyes during fixation, with the emphasis on involuntary movements. The suction cap methods developed by Yarbus were applied

  1. [Dynamic posturography in normal subjects].

    PubMed

    Salami, A; Guglielmetti, G; Bindi, G F; Dellepiane, M

    1990-01-01

    The relative lack of data on the dynamic posturography led us to start a study in order to give our contributions to the standardization of M1, M2, M3, response parameters in normal subjects. Our research was carried out on 35 normal subjects aged 21 to 50. All of them were standing in Romberg's position on a Tönnies model board in a normally lit and ventilated room. We performed two tests: the first one open-eyed staring at no point, the second, 5 minutes later, closed-eyed. The EMG signals were obtained by surface electrodes on triceps sural and front tibial muscles. The EMG recording was determined by a "tilt" movement of the board at a steady speed of 50 per sec. and 4 wide. We use a XT 286 IBM computer with "T POST" software for checking and testing the data. Our results showed a significant variation in the value of the duration parameter in open-eyed and closed-eyed tests. Latency and area values were inferior to those obtained by other authors, except for Diener and Dichgans (3) whose results differ in latency value only.

  2. Recognizing and Treating Eye Injuries

    MedlinePlus

    ... Eye Injuries Reviewed by: Brenda Pagan-Duran MD Mar. 01, 2016 When an eye injury does occur, ... Fireworks Eye Safety Jun 10, 2016 Protective Eyewear Mar 01, 2016 Scleritis Symptoms Mar 01, 2015 What ...

  3. Eye burning - itching and discharge

    MedlinePlus

    ... allergies or hay fever Infections, bacterial or viral ( conjunctivitis or pink eye) Chemical irritants (such as chlorine ... to help with allergies. Pink eye or viral conjunctivitis causes a red or bloodshot eye and excessive ...

  4. Mycoplasma and associated bacteria isolated from ovine pink-eye.

    PubMed

    Langford, E V

    1971-01-01

    A mycoplasma was recovered from the untreated conjunctival membranes of nine sheep affected by Pink-eye. It was neither isolated from the conjunctiva of treated animals which were affected nor from the conjunctiva of normal animals either in contact or not in contact with affected animals. Bacteria found on normal conjunctival membranes were Neisseria ovis, Escherichia coli, Staphylococcus epidermididis, Streptococcus and Bacillus spp. Bacteria found in clinical cases of Pink-eye were N. ovis, E. coli, a Streptococcus and Pseudomonas spp.

  5. Eye development in the Cape dune mole rat.

    PubMed

    Nikitina, Natalya V; Kidson, Susan H

    2014-03-01

    Studies on mammalian species with naturally reduced eyes can provide valuable insights into the evolutionary developmental mechanisms underlying the reduction of the eye structures. Because few naturally microphthalmic animals have been studied and eye reduction must have evolved independently in many of the modern groups, novel evolutionary developmental models for eye research have to be sought. Here, we present a first report on embryonic eye development in the Cape dune mole rat, Bathyergus suillus. The eyes of these animals contain all the internal structures characteristic of the normal eye but exhibit abnormalities in the anterior chamber structures. The lens is small but develops normally and exhibits a normal expression of α- and γ-crystallins. One of the interesting features of these animals is an extremely enlarged and highly pigmented ciliary body. In order to understand the molecular basis of this unusual feature, the expression pattern of an early marker of the ciliary zone, Ptmb4, was investigated in this animal. Surprisingly, in situ hybridization results revealed that Ptmb4 expression was absent from the ciliary body zone of the developing Bathyergus eye.

  6. Cyanoacrylate Adhesives in Eye Wounds.

    DTIC Science & Technology

    EYE, *WOUNDS AND INJURIES), (*ADHESIVES, EYE), (*ACRYLIC RESINS, ADHESIVES), CORNEA , HEALING, TISSUES(BIOLOGY), TOLERANCES(PHYSIOLOGY), NECROSIS, SURGICAL SUPPLIES, STRENGTH(PHYSIOLOGY), SURGERY, THERAPY

  7. Advocacy for eye care.

    PubMed

    Ravilla, Thulasiraj D; Ramasamy, Dhivya

    2012-01-01

    The effectiveness of eye care service delivery is often dependant on how the different stakeholders are aligned. These stakeholders range from the ministries of health who have the capacity to grant government subsidies for eye care, down to the primary healthcare workers who can be enrolled to screen for basic eye diseases. Advocacy is a tool that can help service providers draw the attention of key stakeholders to a particular area of concern. By enlisting the support, endorsement and participation of a wider circle of players, advocacy can help to improve the penetration and effectiveness of the services provided. There are several factors in the external environmental that influence the eye care services - such as the availability of trained manpower, supply of eye care consumables, government rules and regulations. There are several instances where successful advocacy has helped to create an enabling environment for eye care service delivery. Providing eye care services in developing countries requires the support - either for direct patient care or for support services such as producing trained manpower or for research and dissemination. Such support, in the form of financial or other resources, can be garnered through advocacy.

  8. Xenon contrast CT-CBF scanning of the brain differentiates normal age-related changes from multi-infarct dementia and senile dementia of Alzheimer type

    SciTech Connect

    Tachibana, H.; Meyer, J.S.; Okayasu, H.; Shaw, T.G.; Kandula, P.; Rogers, R.L.

    1984-07-01

    Local cerebral blood flow (LCBF) and partition coefficients (L lambda) were measured during inhalation of stable xenon gas with serial CT scanning among normal volunteers (N . 15), individuals with multi-infarct dementia (MID, N . 10), and persons with senile dementia of Alzheimer type (SDAT, N . 8). Mean gray matter flow values were reduced in both MID and SDAT. Age-related declines in LCBF values in normals were marked in frontal cortex and basal ganglia. LCBF values were decreased beyond normals in frontal and temporal cortices and thalamus in MID and SDAT, in basal ganglia only in MID. Unlike SDAT and age-matched normals, L lambda values were reduced in fronto-temporal cortex and thalamus in MID. Multifocal nature of lesions in MID was apparent. Coefficients of variation for LCBFs were greater in MID compared with SDAT and/or age-matched normals.

  9. Personal identification by eyes.

    PubMed

    Marinović, Dunja; Njirić, Sanja; Coklo, Miran; Muzić, Vedrana

    2011-09-01

    Identification of persons through the eyes is in the field of biometrical science. Many security systems are based on biometric methods of personal identification, to determine whether a person is presenting itself truly. The human eye contains an extremely large number of individual characteristics that make it particularly suitable for the process of identifying a person. Today, the eye is considered to be one of the most reliable body parts for human identification. Systems using iris recognition are among the most secure biometric systems.

  10. An eye movement technique for correlating fixational target eye movements with location on the retinal image.

    PubMed

    Barrett, S F; Zwick, H

    2000-01-01

    Recent investigation demonstrate that ocular motility in eyes with retinal pathology may show a lower propensity to visit such areas of the retina as compared to non-pathological retinal sites. While current ophthalmic instruments with the ability to image both the retina and visual function test target placement on the retina have provided this observation, the ability to quantify in real time these images as an eye movement measurement is presently lacking and the objective of this paper. A Rodenstock confocal scanning ophthalmoscope (CSLO) was used to image the retina during the performance of a visual fixation task. Direct observation of acuity target placement at the retina under continuous viewing conditions was possible with this apparatus. Target fixation eye movement images of the retina were rapidly digitized from video tape records and registered using a specialized rapid retinal image tracking algorithm. Fixational eye movement pattern densities at the retina were derived from these data. Preliminary data obtained demonstrate the utility of this technique in quantifying fixation eye movement patterns observed in three human patients with vocation-related laser retinal injury. In all patients, areas of severe retinal damage was generally avoided. The density of ocular eye movement tends to reflect regions of retinal normality and avoidance of retinal regions with severe pathology. Variation in eye movement density may exist where pathology is less severe.

  11. Choroidal thickness evaluation of healthy eyes, central serous chorioretinopathy, and fellow eyes using spectral domain optical coherence tomography in Indian population

    PubMed Central

    Arora, Supriya; Pyare, Richa; Sridharan, Preethi; Arora, Tarun; Thakar, Meenakshi; Ghosh, Basudeb

    2016-01-01

    Aim: The purpose of this study is to establish a normative database of subfoveal choroidal thickness (CT) in healthy young Indians using spectral domain optical coherence tomography (SD OCT). Evaluation and comparison of CT of central serous chorioretinopathy (CSC) and fellow eyes were also performed. Materials and Methods: This was a prospective, cross-sectional, and observational study. It included 112 normal eyes of 112 healthy volunteers who had no evidence of ocular or systemic disease, 84 CSC eyes with acute, treatment-naïve CSC, and 69 fellow eyes with no evidence of neurosensory detachment or pigment epithelium detachment on SD OCT. Complete history, examination, and SD OCT were performed in all eyes. Results: The mean age of 81 patients (84 eyes) with CSC was 35.04 ± 8.86 years, 69 fellow eyes was 34.61 ± 8.71 years, and 112 healthy volunteers (112 eyes) was 33.16 ± 9.4 years (P < 0.05). The mean subfoveal CT of CSC eyes was 429 ± 74.18 μ, fellow eyes was 360 ± 57.99 μ, and normal eyes was 301.80 ± 46.59 μ (P < 0.001). Conclusion: CT varies not only with age, axial length, and refractive error but also with races. Therefore, it is important to establish a normative database in a particular population before carrying out further research in diseased states. CT in CSC eyes is significantly thicker than fellow eyes, and CT of fellow eyes is significantly thicker than normal eyes. This reinforces the fact that choroidal permeability is increased in both eyes of patients with CSC. PMID:27905337

  12. LASIK eye surgery

    MedlinePlus

    Laser-Assisted In Situ Keratomileusis; Laser vision correction; Nearsightedness - Lasik; Myopia - Lasik ... length of the eye. LASIK uses an excimer laser (an ultraviolet laser) to remove a thin layer ...

  13. Anatomy of the Eye

    MedlinePlus

    ... the eye. It is disc shaped with a hole in the middle (the pupil). Muscles in the ... of photoreceptors are rods and cones. Rods perceive black and white and serve night vision primarily. Cones ...

  14. Eye Injuries (For Parents)

    MedlinePlus

    ... if the foreign body has been flushed out. Seek Medical Care If Your Child Has: been struck ... eyelid an eye that's very sensitive to light Seek Emergency Care Immediately If Your Child Has: trouble ...

  15. What Is Eye Cancer?

    MedlinePlus

    ... of cancers, see our documents on them. Intraocular melanoma (melanoma of the eye) Intraocular melanoma is the most ... the rest of this document focuses on intraocular melanomas and lymphomas. Written by References The American Cancer ...

  16. Laser photocoagulation - eye

    MedlinePlus

    ... the retina that provides sharp central vision (macular edema) This surgery also treats the following eye problems: ... in time. If your treatment was for macular edema, your vision may seem worse for a few ...

  17. Multimodal eye recognition

    NASA Astrophysics Data System (ADS)

    Zhou, Zhi; Du, Yingzi; Thomas, N. L.; Delp, Edward J., III

    2010-04-01

    Multimodal biometrics use more than one means of biometric identification to achieve higher recognition accuracy, since sometimes a unimodal biometric is not good enough used to do identification and classification. In this paper, we proposed a multimodal eye recognition system, which can obtain both iris and sclera patterns from one color eye image. Gabor filter and 1-D Log-Gabor filter algorithms have been applied as the iris recognition algorithms. In sclera recognition, we introduced automatic sclera segmentation, sclera pattern enhancement, sclera pattern template generation, and sclera pattern matching. We applied kernelbased matching score fusion to improve the performance of the eye recognition system. The experimental results show that the proposed eye recognition method can achieve better performance compared to unimodal biometric identification, and the accuracy of our proposed kernel-based matching score fusion method is higher than two classic linear matching score fusion methods: Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA).

  18. Dry eye syndrome

    MedlinePlus

    ... of dry eyes include: Dry environment or workplace (wind, air conditioning) Sun exposure Smoking or second-hand ... NOT smoke and avoid second-hand smoke, direct wind, and air conditioning. Use a humidifier, especially in ...

  19. Amblyopia: Lazy Eye Symptoms

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  20. Using Eye Makeup

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  1. Amblyopia: Lazy Eye Diagnosis

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  2. Smoking and Eye Health

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  3. LASIK - Laser Eye Surgery

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  4. Amblyopia: Lazy Eye Treatment

    MedlinePlus

    ... Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Academy Publications EyeNet Ophthalmology Information for: International Ophthalmologists Media Medical Students Patients and Public Technicians and Nurses ...

  5. Melanoma of the eye

    MedlinePlus

    Small melanomas may be treated with: Surgery Laser Radiation therapy (such as Gamma Knife , CyberKnife , brachytherapy) Surgery to remove the eye (enucleation) may be needed. Other treatments that may be used ...

  6. Facts About Pink Eye

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  7. Diagram of the Eye

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  8. Eye Disease Simulations

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  9. Eye Injuries (For Parents)

    MedlinePlus

    ... the eyelid. Others, like those that happen during sports activities, can be serious and require medical attention. Signs and Symptoms redness stinging or burning watering sensitivity to light blurred vision swelling of the eyelids discoloration around the eye ...

  10. Eye pigments in wild-type and eye-color mutant strains of the African malaria vector Anopheles gambiae.

    PubMed

    Beard, C B; Benedict, M Q; Primus, J P; Finnerty, V; Collins, F H

    1995-01-01

    Chromatographic analysis of pigments extracted from wild-type eyes of the mosquito Anopheles gambiae reveals the presence of the ommatin precursor 3-hydroxykynurenine, its transamination derivative xanthurenic acid, and a dark, red-brown pigment spot that probably is composed of two or more low mobility xanthommatins. No colored or fluorescent pteridines are evident. Mosquitoes homozygous for an autosomal recessive mutation at the red-eye (r) locus have a brick-red eye color in larvae, pupae, and young adults, in contrast to the almost black color of the wild eye. Mosquitoes homozygous for this mutant allele have levels of ommochrome precursors that are indistinguishable from the wild-type, but the low-mobility xanthommatin spot is ochre-brown in color rather than red-brown as in the wild-type. Mosquitoes with two different mutant alleles at the X-linked pink-eye locus (p, which confers a pink eye color, and pw, which confers a white eye phenotype in homozygotes or hemizygous males) have normal levels of ommochrome precursors but no detectable xanthommatins. Mosquitoes homozygous for both the r and p mutant alleles have apricot-colored eyes and show no detectable xanthommatins. Both the pink-eye and red-eye mutations appear to involve defects in the transport into or assembly of pigments in the membrane-bound pigment granules rather then defects in ommochrome synthesis.

  11. Changes in Timing and kinematics of goal directed eye-hand movements in early-stage Parkinson’s disease

    PubMed Central

    2013-01-01

    Objective Many daily activities involve intrinsic or extrinsic goal-directed eye and hand movements. An extensive visuomotor coordination network including nigro-striatal pathways is required for efficient timing and positioning of eyes and hands. The aim of this study was to investigate how Parkinson’s disease (PD) affects eye-hand coordination in tasks with different cognitive complexity. Methods We used a touch screen, an eye-tracking device and a motion capturing system to quantify changes in eye-hand coordination in early-stage PD patients (H&Y < 2.5) and age-matched controls. Timing and kinematics of eye and hand were quantified in four eye-hand coordination tasks (pro-tapping, dual planning, anti-tapping and spatial memory task). Results In the pro-tapping task, saccade initiation towards extrinsic goals was not impaired. However, in the dual planning and anti-tapping task initiation of saccades towards intrinsic goals was faster in PD patients. Hand movements were differently affected: initiation of the hand movement was only delayed in the pro-tapping and dual planning task. Overall, hand movements in PD patients were slower executed compared to controls. Interpretation Whereas initiation of saccades in an extrinsic goal-directed task (pro-tapping task) is not affected, early stage PD patients have difficulty in suppressing reflexive saccades towards extrinsic goals in tasks where the endpoint is an intrinsic goal (e.g. dual planning and anti-tapping task). This is specific for eye movements, as hand movements have delayed responses in the pro-tapping and dual planning task. This suggests that reported impairment of the dorsolateral prefrontal cortex in early-stage PD patients affects only inhibition of eye movements. We conclude that timing and kinematics of eye and hand movements in visuomotor tasks are affected in PD patients. This result may have clinical significance by providing a behavioral marker for the early diagnosis of PD. PMID:23298720

  12. Rapid eye movement sleep deprivation decreases long-term potentiation stability and affects some glutamatergic signaling proteins during hippocampal development.

    PubMed

    Lopez, J; Roffwarg, H P; Dreher, A; Bissette, G; Karolewicz, B; Shaffery, J P

    2008-04-22

    Development of the mammalian CNS requires formation and stabilization of neuronal circuits and synaptic connections. Sensory stimulation provided by the environment orchestrates neuronal circuit formation in the waking state. Endogenous sources of activation are also implicated in these processes. Accordingly we hypothesized that sleep, especially rapid eye movement sleep (REMS), the stage characterized by high neuronal activity that is more prominent in development than adulthood, provides endogenous stimulation, which, like sensory input, helps to stabilize and refine neuronal circuits during CNS development. Young (Y: postnatal day (PN) 16) and adolescent (A: PN44) rats were rapid eye movement sleep-deprived (REMSD) by gentle cage-shaking for only 4 h on 3 consecutive days (total 12 h). The effect of REMS deprivation in Y and A rats was tested 3-7 days after the last deprivation session (Y, PN21-25; A, PN49-53) and was compared with younger (immature, I, PN9-12) untreated, age-matched, treated and normal control groups. REMS deprivation negatively affected the stability of long-term potentiation (LTP) in Y but not A animals. LTP instability in Y-REMSD animals was similar to the instability in even the more immature, untreated animals. Utilizing immunoblots, we identified changes in molecular components of glutamatergic synapses known to participate in mechanisms of synaptic refinement and plasticity. Overall, N-methyl-d-aspartate receptor subunit 2B (NR2B), N-methyl-d-aspartate receptor subunit 2A, AMPA receptor subunit 1 (GluR1), postsynaptic density protein 95 (PSD-95), and calcium/calmodulin kinase II tended to be lower in Y REMSD animals (NR2B, GluR1 and PSD-95 were significantly lower) compared with controls, an effect not present in the A animals. Taken together, these data indicate that early-life REMS deprivation reduces stability of hippocampal neuronal circuits, possibly by hindering expression of mature glutamatergic synaptic components. The findings

  13. Corneal temperature in patients with dry eye evaluated by infrared radiation thermometry.

    PubMed Central

    Fujishima, H; Toda, I; Yamada, M; Sato, N; Tsubota, K

    1996-01-01

    AIMS: The corneal temperature change following each blink was investigated in patients with dry eye using an infrared radiation thermometer. METHODS: Twenty patients with dry eye and 20 normal controls were enrolled in this study. Subjects kept their eyes open for 10 seconds without blinking and corneal temperature was measured every second with a recently improved infrared radiation thermometer. RESULTS: In the 20 patients with dry eye, corneal temperature change after keeping the eye open for 10 seconds was 0.21 (SD 0.06) degree C while it was 0.61 (0.28) degree C in the 20 normal patients (p = 0.0001). In an exponential equation, the inclination of the slope of a patient with dry eye was smaller than the normal. The correlation coefficient was r = 0.79 (0.16) in patients with dry eye and r = 0.90 (0.07) in normal patients. The mean K value of patients with dry eye was 0.20 (0.13)/second and that of normal subjects was 0.31 (0.19)/second (p = 0.03). CONCLUSION: Findings demonstrate the usefulness of this thermometer for measuring corneal temperature in the evaluation of dry eye. Decrease in corneal temperature with each blink in patients with dry eye was smaller than in normal subjects. Images PMID:8664227

  14. Modern sports eye injuries

    PubMed Central

    Capão Filipe, J A; Rocha-Sousa, A; Falcão-Reis, F; Castro-Correia, J

    2003-01-01

    Aims: To determine the severity and long term sequelae of eye injuries caused by modern sports that could be responsible for significant ocular trauma in the future. Methods: Prospective observational study of 24 (25 eyes) athletes with sports related ocular injuries from health clubs, war games, adventure, radical and new types of soccer, presenting to an eye emergency department between 1992 and 2002 (10 years). Results: Modern sports were responsible for 8.3% of the 288 total sports eye injuries reported. Squash (29.2%) was the most common cause, followed by paintball (20.8%) and motocross (16.6%). The most common diagnosis during the follow up period was retinal breaks (20%). 18 (75%) patients sustained a severe injury. The final visual acuity remained <20/100 in two paintball players. Conclusions: Ocular injuries resulting from modern sports are often severe. Adequate instruction of the participants in the games, proper use of eye protectors, and a routine complete ophthalmological examination after an eye trauma should be mandatory. PMID:14609827

  15. Eye Protection in Educational Institutions.

    ERIC Educational Resources Information Center

    New Jersey State Dept. of Education, Trenton. Div. of Vocational Education.

    Intended to help reduce the number of school eye injuries in New Jersey, this document begins with a brief review of existing legislation regarding eye protection in educational institutions and a list of elements essential in an eye safety program. Second, eye protection equipment is examined in terms of: the advantages of safety spectacles over…

  16. Alteration of Galectin-3 in Tears of Patients with Dry Eye Disease

    PubMed Central

    Uchino, Yuichi; Mauris, Jerome; Woodward, Ashley M.; Dieckow, Julia; Amparo, Francisco; Dana, Reza; Mantelli, Flavio; Argüeso, Pablo

    2015-01-01

    Purpose To investigate the expression, release, and proteolytic degradation of galectin-3 in patients with dry eye disease. Design Observational case series with a comparison group. Methods Tear washes and conjunctival impression cytology specimens were collected through standard procedures from 16 patients with dry eye and 11 age-matched healthy subjects. Galectin-3 content in tears was analyzed by quantitative Western blot, using recombinant galectin-3 protein to generate a calibration curve. The relative expression of galectin-3 and matrix metalloproteinase 9 (MMP9) was evaluated by quantitative polymerase chain reaction. The cleavage of galectin-3 was studied in vitro using activated recombinant MMP9 and protease inhibitors. Results The concentration of galectin-3 protein in tears, but not galectin-3 expression in conjunctival epithelium, was significantly higher in tears of patients with dry eye (0.38 ng/μg total protein, range 0.04-1.36) compared to healthy subjects (0.12 ng/μg total protein, range 0.00-0.41) (P < .01). By Western blot, an intact (∼28.0 kDa) galectin-3 band was identified in tear samples from healthy subjects, whereas 50% of the dry eye samples were characterized by the additional presence of a partially degraded form (∼25.4 kDa). In our experiments, elevated expression of MMP9 in dry eye subjects correlated with the ability of active MMP9 to cleave galectin-3 from recombinant origin. Interestingly, cleavage of endogenous galectin-3 in tear samples was impaired using a broad-spectrum proteinase inhibitor cocktail, but not the pan-specific MMP inhibitor GM6001, suggesting the presence of proteases other than MMPs in promoting galectin-3 degradation in dry eye. Conclusions Our results indicate that release of cellular galectin-3 into tears is associated with epithelial dysfunction in dry eye, and that galectin-3 proteolytic cleavage may contribute to impaired ocular surface barrier function. PMID:25703476

  17. Exposure of eyes to perfume: a double-blind, placebo-controlled experiment.

    PubMed

    Elberling, J; Duus Johansen, J; Dirksen, A; Mosbech, H

    2006-08-01

    Environmental perfume exposure can elicit bothersome respiratory symptoms. Symptoms are induced at exposure levels which most people find tolerable, and the mechanisms are unclear. The aim of the study was to investigate patients with eye and respiratory symptoms related to environmental perfume, by exposing the eyes to perfume in a double-blind, placebo-controlled study.Twenty-one eczema patients with respiratory symptoms elicited by perfume were compared with 21 healthy volunteers in a sex- and age-matched case-control study. The participants completed a symptom questionnaire, and underwent a double-blind, placebo-controlled exposure to perfume. Of the 42 individuals tested, 10 had more eye symptoms (irritation, itching, and tears) during perfume exposure than during placebo exposures, and eight of these individuals (P = 0.07, Fisher's exact test) belonged to the patient group. A true positive eye reaction to perfume was significantly associated with identification of perfume as an active exposure (P < 0.05). In this study, vapor of perfume elicited irritation in the eyes independently of olfaction, but the relative importance of ocular chemoperception in relation to elicitation of respiratory symptoms from common environmental exposures to perfume remains unclear. We investigated the hypothesis of an association between respiratory symptoms related to perfume and ocular perfume sensitivity by exposing the eyes to perfume in a double blind, placebo-controlled experiment. Vapors of perfume provoked symptoms in the relevant eye in some patients and healthy control persons, but under our exposure conditions, ocular chemesthesis failed to elicit respiratory symptoms.

  18. Brief light exposure at night disrupts the circadian rhythms in eye growth and choroidal thickness in chicks.

    PubMed

    Nickla, Debora L; Totonelly, Kristen

    2016-05-01

    Changes in ocular growth that lead to myopia or hyperopia are associated with alterations in the circadian rhythms in eye growth, choroidal thickness and intraocular pressure in animal models of emmetropization. Recent studies have shown that light at night has deleterious effects on human health, acting via "circadian disruptions" of various diurnal rhythms, including changes in phase or amplitude. The purpose of this study was to determine the effects of brief, 2-h episodes of light in the middle of the night on the rhythms in axial length and choroidal thickness, and whether these alter eye growth and refractive error in the chick model of myopia. Starting at 2 weeks of age, birds received 2 h of light between 12:00 am and 2:00 am for 7 days (n = 12; total hours of light: 14 h). Age-matched controls had a continuous dark night (n = 14; 14L/10D). Ocular dimensions were measured using high-frequency A-scan ultrasonography on the first day of the experiment, and again on day 7, at 6-h intervals, starting at noon (12 pm, 6 pm, 12 am, 6 am, 12 pm). Measurements during the night were done under a photographic safe-light. These data were used to determine rhythm parameters of phase and amplitude. 2 groups of birds, both experimental (light at night) and control, were measured with ultrasound at various intervals over the course of 4 weeks to determine growth rates. Refractive errors were measured in 6 experimental and 6 control birds at the end of 2 weeks. Eyes of birds in a normal L/D cycle showed sinusoidal 24-h period diurnal rhythms in axial length and choroid thickness. Light in the middle of the night caused changes in both the rhythms in axial length and choroidal thickness, such that neither could be fit to a sine function having a period of 24 h. Light caused an acute, transient stimulation in ocular growth rate in the subsequent 6-h period (12 am-6 am), that may be responsible for the increased growth rate seen 4 weeks later, and the more

  19. The injured eye

    PubMed Central

    Scott, Robert

    2011-01-01

    Eye injuries come at a high cost to society and are avoidable. Ocular blast injuries can be primary, from the blast wave itself; secondary, from fragments carried by the blast wind; tertiary; due to structural collapse or being thrown against a fixed object; or quaternary, from burns and indirect injuries. Ballistic eye protection significantly reduces the incidence of eye injuries and should be encouraged from an early stage in Military training. Management of an injured eye requires meticulous history taking, evaluation of vision that measures the acuity and if there is a relative pupillary defect as well as careful inspection of the eyes, under anaesthetic if necessary. A lateral canthotomy with cantholysis should be performed immediately if there is a sight-threatening retrobulbar haemorrhage. Systemic antibiotics should be prescribed if there is a suspected penetrating or perforating injury. A ruptured globe should be protected by an eye shield. Primary repair of ruptured globes should be performed in a timely fashion. Secondary procedures will often be required at a later date to achieve sight preservation. A poor initial visual acuity is not a guarantee of a poor final result. The final result can be predicted after approximately 3–4 weeks. Future research in eye injuries attempts to reduce scarring and neuronal damage as well as to promote photoreceptor rescue, using post-transcriptional inhibition of cell death pathways and vaccination to promote neural recovery. Where the sight has been lost sensory substitution of a picture from a spectacle mounted video camera to the touch receptors of the tongue can be used to achieve appreciation of the outside world. PMID:21149360

  20. Eye Motility Alterations in Retinitis Pigmentosa.

    PubMed

    Migliorini, Raffaele; Comberiati, Anna Maria; Galeoto, Giovanni; Fratipietro, Manuela; Arrico, Loredana

    2015-01-01

    Purpose. We evaluated a sample of individuals with retinitis pigmentosa (RP) with the aim of assessing the presence or absence of ocular motility (OM) disorders. Materials and Methods. We included 23 out of the 25 individuals from the sample (9 females and 14 males) with an average visual acuity of 6/10. Results. The cover test about the vertical deviation in near distance showed an r/l in 3.45% and an l/r in 6.9%. The assessment of OM showed that 39.1% of the sample had a severe hyperfunction of the IO of the right eye and a severe hyperfunction (34.5%) of the SO of the left eye; 21.8% had a moderate hypofunction of right SO with a moderate percentage of hypofunction of 17.5% for the SO of the left eye; 30.5%, however, showed a serious hypofunction of the SR of both eyes; 21.7% of the sample showed a hyperfunction in both eyes of the IR. Conclusion. This alteration, however, is not attributable to either a high refractive defect (medium-low myopia: -1 diopter ±3 SD) or to a severely impaired binocular vision (visual acuity, motor fusion, and stereopsis are normal or within a range of values commonly accepted). Therefore, the disorders of OM lead to a genetic origin.

  1. Vergence Eye Movements in Patients with Schizophrenia

    PubMed Central

    Bolding, MS; Lahti, AC; White, D; Moore, C; Gurler, D; Gawne, TJ; Gamlin, PD

    2014-01-01

    Previous studies have shown that smooth pursuit eye movements are impaired in patients with schizophrenia. However, under normal viewing conditions, targets move not only in the frontoparallel plane but also in depth, and tracking them requires both smooth pursuit and vergence eye movements. Although previous studies in humans and non-human primates suggest that these two eye movement subsystems are relatively independent of one another, to our knowledge, there have been no prior studies of vergence tracking behavior in patients with schizophrenia. Therefore, we have investigated these eye movements in patients with schizophrenia and in healthy controls. We found that patients with schizophrenia exhibited substantially lower gains compared to healthy controls during vergence tracking at all tested speeds (e.g. 0.25 Hz vergence tracking mean gain of 0.59 vs. 0.86). Further, consistent with previous reports, patients with schizophrenia exhibited significantly lower gains than healthy controls during smooth pursuit at higher target speeds (e.g. 0.5 Hz smooth pursuit mean gain of 0.64 vs. 0.73). In addition, there was a modest (r≈0.5), but significant, correlation between smooth pursuit and vergence tracking performance in patients with schizophrenia. Our observations clearly demonstrate substantial vergence tracking deficits in patients with schizophrenia. In these patients, deficits for smooth pursuit and vergence tracking are partially correlated suggesting overlap in the central control of smooth pursuit and vergence eye movements. PMID:25088242

  2. Iron homeostasis and eye disease

    PubMed Central

    Loh, Allison; Hadziahmetovic, Majda; Dunaief, Joshua L.

    2009-01-01

    Summary Iron is necessary for life, but excess iron can be toxic to tissues. Iron is thought to damage tissues primarily by generating oxygen free radicals through the Fenton reaction. We present an overview of the evidence supporting iron's potential contribution to a broad range of eye disease using an anatomical approach. Firstly, iron can be visualized in the cornea as iron lines in the normal aging cornea as well as in diseases like keratoconus and pterygium. In the lens, we present the evidence for the role of oxidative damage in cataractogenesis. Also, we review the evidence that iron may play a role in the pathogenesis of the retinal disease age-related macular degeneration. Although currently there is no direct link between excess iron and development of optic neuropathies, ferrous iron's ability to form highly reactive oxygen species may play a role in optic nerve pathology. Lastly, we discuss recent advances in prevention and therapeutics for eye disease with antioxidants and iron chelators,. PMID:19059309

  3. Laser eye protection

    NASA Astrophysics Data System (ADS)

    Allen, Ralph G.; Labo, Jack A.; Mayo, Michael W.

    1990-07-01

    Laser applications have proliferated in recent years and as to be expected their presence is no longer confined to the laboratory or places where access to their radiation can be easily controlled. One obvious application where this is so is in military operations where various devices such as laser range finders target designators and secure communications equipment elevate the risk of exposure specifically eye exposure to unacceptable levels. Although the need for eye protection in the laboratory and other controlled areas has been appreciated since the invention of the laser the use of lasers in circumstances where safety or the risk of temporary loss of vision which can not always be ensured by administrative procedures has made adequate eye protection essential. It is the critical nature of many military operations that has driven the search for eye protection against both nuclear and laser radiation. At the same time the requirement to maintain useful vision during irradiation as well as advances in laser technology have complicated the problem enormously. Pertinent aspects of the problem such as laser characteristics- -pulse width repetition rate laser wavelength tunability or agility as well as laser power or energy have been placed in perspective. In addition possible effects on vision for various exposures have been estimated as have the characteristics required of eye protective devices. Various classes of devices are discussed and advantages and disadvantages noted. 1.

  4. Don't it make my blue eyes brown: heterochromia and other abnormalities of the iris.

    PubMed

    Rennie, I G

    2012-01-01

    Eye colour is one of the most important characteristics in determining facial appearance. In this paper I shall discuss the anatomy and genetics of normal eye colour, together with a wide and diverse range of conditions that may produce an alteration in normal iris pigmentation or form.

  5. Don't it make my blue eyes brown: heterochromia and other abnormalities of the iris

    PubMed Central

    Rennie, I G

    2012-01-01

    Eye colour is one of the most important characteristics in determining facial appearance. In this paper I shall discuss the anatomy and genetics of normal eye colour, together with a wide and diverse range of conditions that may produce an alteration in normal iris pigmentation or form. PMID:21979861

  6. Compound eye formation in the termite Incisitermes minor (Isoptera: Kalotermitidae).

    PubMed

    Rose, Taylor C; Ediger, Emily F; Lehman-Schletewitz, Joy; McClane, Nathan W; Schweigert, Kristen C; Alzweideh, Saif; Wadsworth, Lauren; Husseneder, Claudia; Morris, Joshua W; Ziesmann, Jurgen

    2015-07-01

    The postembryonic development and caste differentiation patterns of lower termites have been described multiple times in a variety of different species. However, most of these studies focused on gross ontogeny, without carefully describing the maturation of any particular organ or organ system. The few studies that have attempted to correlate caste development and organ differentiation have produced somewhat inconsistent results, especially in the area of eye formation. Therefore, in order to help further elucidate the relationship between eye formation and postembryonic differentiation in lower termites, we studied eye development in the termite, Incisitermes minor (Hagen). Eye formation in I. minor began in the earliest larvae, with only an eye primordium. However, in all later larval stages, characteristic eye structures were observed and were shown to progressively differentiate through larval and nymphal stages. Curiously, pigmentation began with three to eight groups of cells in early larvae and the number of these pigmented groups increased along the developmental time course. Ultimately, a uniformly pigmented eye area was formed by the early nymphal stage. The overall eye area also gradually increased along with normal caste development, but the characteristic lenses seen in a prototypical insect compound eye did not completely form until after the final nymphal stage. Electrophysiological measurements provided clear evidence that eyes were indeed functional at all stages of development where pigment was present. Based upon this data, the eye development pattern in I. minor appeared to follow a divergent pathway from holometabolous insects and an intermediate pathway between typical hemimetabolous eye development and the heterochronic shift observed in other termite species.

  7. Eye screening in the elderly.

    PubMed

    Keane, E M; O'Connor, M; Coakley, D; Walsh, J B

    1997-01-01

    Poor vision is considered to be a common unreported illness in the elderly population. To determine its prevalence we carried out an eye screen on 150 randomly selected co-operative elderly subjects attending St James's Hospital. A database [mean age 78.2 years (range 65 to 97)], medical history, mini-mental test score [mean score 9.1 (range 2 to 10)], mobility assessment and history of eye problems was gathered. A visual test of both eyes together (standard N6 and N8), inspection of the eyes, tonometry (Perkin's handheld tonometer) and fundoscopy were performed on each subject and the need and reason for referral to an optician or an ophthalmologist was documented. Results show that 64% of subjects could read N6 or N8. Tonometry revealed no subject with raised intraocular pressure, including 4 subjects who were currently on treatment for glaucoma. Fundoscopy showed that 57.3% of subjects had some evidence of cataracts, 16.6% moderate and 3% severe. The retina appeared normal in 58.6% of subjects, 20.6% of the population had hypertensive changes, 4.6% had diabetic changes, 3% had optic atrophy, 1.3% had macular degeneration and a further 10% could not be clearly visualised due to cataracts. 90% of subjects wore glasses and the average duration since the glasses were last changed was 3.7 years (range 2 weeks to 20 years). No glasses examined were in need of cleaning or repair. 36% of subjects could not read N8 (28 of these had forgotten their glasses and were advised to visit their optician if they could not read newsprint). 7.3% of subjects were referred to an optician for new glasses, 1.3% were referred to an ophthalmologist for newly diagnosed cataracts and 6.6% were regular attenders to an ophthalmologist. We conclude that the rate of new referrals for the occurrence of correctable undetected visual acuity deficit was lower than expected at 8.6% of subjects screened.

  8. Multivariate normality

    NASA Technical Reports Server (NTRS)

    Crutcher, H. L.; Falls, L. W.

    1976-01-01

    Sets of experimentally determined or routinely observed data provide information about the past, present and, hopefully, future sets of similarly produced data. An infinite set of statistical models exists which may be used to describe the data sets. The normal distribution is one model. If it serves at all, it serves well. If a data set, or a transformation of the set, representative of a larger population can be described by the normal distribution, then valid statistical inferences can be drawn. There are several tests which may be applied to a data set to determine whether the univariate normal model adequately describes the set. The chi-square test based on Pearson's work in the late nineteenth and early twentieth centuries is often used. Like all tests, it has some weaknesses which are discussed in elementary texts. Extension of the chi-square test to the multivariate normal model is provided. Tables and graphs permit easier application of the test in the higher dimensions. Several examples, using recorded data, illustrate the procedures. Tests of maximum absolute differences, mean sum of squares of residuals, runs and changes of sign are included in these tests. Dimensions one through five with selected sample sizes 11 to 101 are used to illustrate the statistical tests developed.

  9. Aetiological Factors in Dyslexia: I. Saccadic Eye Movement Control.

    ERIC Educational Resources Information Center

    Leisman, Gerald; Schwartz, Joddy

    1978-01-01

    A study examined the character of saccadic eye movement (as reflected by duration/amplitude and velocity/amplitude functions) in 20 dyslexic and 20 normal children (mean age 8.2 years) and 28 normal adults (mean age 26.2 years). (Author/PHR)

  10. Photorefraction of the Eye

    NASA Astrophysics Data System (ADS)

    Colicchia, Giuseppe; Wiesner, Hartmut; Zollman, Dean

    2015-02-01

    Photorefraction is a method to easily estimate the refractive state of the eye. The principle of photorefraction involves projecting light into the eye during flash photography and then examining the paths of light that emerge from the pupil after scattering on the back portion of the interior of the eyeball (fundus). We will explain the optical principles underlying the method for eccentric photorefraction and describe how students can perform it using current digital cameras. Our purpose is not to diagnose refractive errors reliably, but to use devices popular among young people that, in combination with an important ophthalmic context, may be successful in improving students' interest for learning optical concepts.

  11. Eye pathologies in neonates

    PubMed Central

    Mansoor, Nyaish; Mansoor, Tihami; Ahmed, Mansoor

    2016-01-01

    In the United Kingdom, newborn assessment incorporates a screening eye examination for any structural abnormalities, observation of neonate's visual behaviour and direct ophthalmoscopy examination looking for red reflex. Early identification and immediate management of eye related pathologies should commence soon after birth as early diagnosis and prompt intervention may have significant impact on the prognosis for many potentially blinding but treatable disorders such as congenital cataracts and retinoblastoma. If left undetected and untreated, such problems may potentially lead to irreversible damage to the vision which persists into adulthood resulting in lack of self-confidence together with difficulties in educational attainment and job opportunities. PMID:28003988

  12. Comparative Study of Anterior Eye Segment Measurements with Spectral Swept-Source and Time-Domain Optical Coherence Tomography in Eyes with Corneal Dystrophies

    PubMed Central

    Nowinska, Anna K.; Teper, Sławomir J.; Janiszewska, Dominika A.; Lyssek-Boron, Anita; Dobrowolski, Dariusz; Koprowski, Robert; Wylegala, Edward

    2015-01-01

    Purpose. To compare anterior eye segment measurements and morphology obtained with two optical coherence tomography systems (TD OCT, SS OCT) in eyes with corneal dystrophies (CDs). Methods. Fifty healthy volunteers (50 eyes) and 54 patients (96 eyes) diagnosed with CD (epithelial basement membrane dystrophy, EBMD = 12 eyes; Thiel-Behnke CD = 6 eyes; lattice CD TGFBI type = 15 eyes; granular CD type 1 = 7 eyes, granular CD type 2 = 2 eyes; macular CD = 23 eyes; and Fuchs endothelial CD = 31 eyes) were recruited for the study. Automated and manual central corneal thickness (aCCT, mCCT), anterior chamber depth (ACD), and nasal and temporal trabecular iris angle (nTIA, tTIA) were measured and compared with Bland-Altman plots. Results. Good agreement between the TD and SS OCT measurements was demonstrated for mCCT and aCCT in normal individuals and for mCCT in the CDs group. The ACD, nTIA, and tTIA measurements differed significantly in both groups. TBCD, LCD, and FECD caused increased CCT. MCD caused significant corneal thinning. FECD affected all analyzed parameters. Conclusions. Better agreement between SS OCT and TD OCT measurements was demonstrated in normal individuals compared to the CDs group. OCT provides comprehensive corneal deposits analysis and demonstrates the association of CD with CCT, ACD, and TIA measurements. PMID:26457303

  13. Eye evolution: two eyes can be better than one.

    PubMed

    Foster, Kenneth W

    2009-03-10

    The development of our eyes is owed in part to ancestral structures which functioned in phototaxis. With the origin of bilateral annelid larva, two eyes co-evolved with neurons to improve phototaxis performance.

  14. Indian Soldiers Need Eye Protection

    PubMed Central

    2017-01-01

    Combat-related eye injuries entail enormous financial, social and psychological cost. Military Combat Eye Protection (MCEP) decreases both the incidence and severity of eye injuries. Experts have recognised the need for MCEP for Indian soldiers. We aim to review the combat-related eye injuries and combat eye protection among the Indian soldiers. Global practices of MCEP are also reviewed. We also aim to offer our recommendations for Indian soldiers. We carried out Medline search for combat-related eye injuries and MCEP and separately searched for eye injuries among Indian soldiers during war and other operations. We present the findings as results. Recommendations are based on the opinions of the experts. Combat-related eye injuries increased from 3% of injured in the 1965 Indo-Pakistan War to 4.8% in 1971 war. During peace-keeping operations in Sri Lanka (1987-89) eye injuries increased to 10.5% of the injured. Statistics on eye injuries during counterinsurgency operations are not available. MCEP have shown reduction in eye injuries, and thus MCEP forms a part of personal equipment of the soldiers in developed countries. Indian soldiers do not have provision of MCEP. Combat-related eye injuries among Indian Army soldiers have been increasing. Data on eye injuries during counterinsurgency operations are not available. Indian soldiers do not have provision of MCEP. Provision of MCEP is therefore desirable. Awareness program among the commanders and the soldiers shall result in attitudinal changes and increased compliance. PMID:28384904

  15. Inter-eye comparison of retinal oximetry and vessel caliber between eyes with asymmetrical glaucoma severity in different glaucoma subtypes

    PubMed Central

    Cheng, Clarissa Shu Ming; Lee, Yi Fang; Ong, Charles; Yap, Zhu Li; Tsai, Andrew; Mohla, Aditi; Nongpiur, Monisha E; Aung, Tin; Perera, Shamira A

    2016-01-01

    Background To compare retinal vessel oxygenation and vessel caliber in primary angle-closure glaucoma (PACG), primary open-angle glaucoma (POAG), normal-tension glaucoma (NTG), and normal controls, as well as between eyes of asymmetrical glaucoma severity. Methods This was a prospective, cross-sectional study. The 159 subjects (PACG, n=39; POAG, n=41; NTG, n=41; normal controls, n=38) underwent retinal oxygen saturation measurements using the Oxymap T1 Retinal Oximeter, optical coherence tomography, and Humphrey visual field testing. Retinal oxygen saturation and vessel diameter were compared between the glaucoma groups and normal controls, as well as between eyes of asymmetrical glaucoma severity. Kruskal–Wallis test was performed for comparison among different subtypes of glaucoma. Wilcoxon signed-rank test was used to compare the inter-eye differences. Results Compared to normal controls, arteriolar oxygen saturation was increased in PACG eyes (P=0.048) but not in POAG or NTG eyes. There were no significant differences in oxygen saturation in venules or arteriovenous (AV) difference in all three glaucoma groups. Venular diameter was significantly reduced in all glaucoma groups compared to normal controls (P<0.001), but no such change was observed in arteriolar diameter (P=0.10). When comparing between eyes of asymmetrical glaucoma severity, arteriolar oxygen saturation (P=0.03) and AV difference (P=0.04) were significantly higher, while arteriolar diameter was significantly lower (P=0.001) in the worse eye in PACG group. There were no significant differences in oximetric parameters or vessel calibers between the worse and the better eyes in POAG and NTG groups. Conclusion Eyes with PACG showed increased arteriolar oxygen saturation and increased AV difference. This was not observed in POAG and NTG eyes. Arteriolar diameter in PACG and venular diameter in all three glaucoma groups were reduced. The difference observed in PACG eyes may be due to an increased

  16. The eye of Vesalius.

    PubMed

    De Laey, Jean J

    2011-05-01

    In the time of Vesalius, knowledge of ocular anatomy was limited. The first description of the anatomy of the eye comes from Democrites, for whom the eye was surrounded by two 'coats', filled with a homogenous fluid. The optic nerve was hollow and the lens was considered to be a postmortem artefact. Until the 15th century AD, medicine was influenced by the writings of Galenus and the model of the eye he proposed was still considered valid, even after Vesalius. According to the Alexandrian tradition, the lens was considered as the seat of visual perception. Although Vesalius rightly deserves the title of father of modern anatomy, his description of ocular anatomy was rudimentary and often incorrect. He described a musculus retractorius bulbi, which is found only in lower mammals, not in primates. The lens, the role of which as an optical device he recognized correctly, was placed too centrally in the eye. The optic nerve was not correctly placed and, following Galenus, Vesalius described only seven cranial nerves. The Galenian concept of ocular anatomy was to endure until the development of the microscope by Anthony van Leeuwenhoek. Modern ocular anatomy, in fact, can be dated from the works of Zinn.

  17. Eyes for Learning

    ERIC Educational Resources Information Center

    Orfield, Antonia

    2008-01-01

    Vision is the dominant sense, and the eyes are connected with almost every other part of the brain. If the vision system is poorly developed, children trying to learn suffer. Without good up close vision, students are handicapped even if no one knows or suspects it--they may not even know it themselves. Students do not know that the way they see…

  18. Eye of the Beholder

    ERIC Educational Resources Information Center

    Rogers, Michael

    2010-01-01

    Art, like beauty, as the adage goes, is in the eye of the beholder. Art also is a living, breathing thing that evolves over time, so what is considered "art" is ever changing--how many of the great artists whose works today sell for fortunes were failures during their lifetime? The 20th century unknowingly gave birth to new variations of art that…

  19. The Eyes Have It

    NASA Technical Reports Server (NTRS)

    1999-01-01

    NASA'S Ames Research Center contracted with SRI international to contract a device that would be able to anticipate, track, and monitor involuntary ocular movement horizontally, vertically, and with respect to depth-of-field. This development helped research institutions to understand the eye. The Eyetracker, manufactured and distributed by Forward Optical Technologies, Inc. is now used in the clinical/medical field.

  20. Administering Eye Medications.

    ERIC Educational Resources Information Center

    Morris, Sara; Michael, Nancy, Ed.

    This module on administering eye medications is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. A brief discussion follows of…

  1. Eye-controlled ''teletypewriter''

    NASA Technical Reports Server (NTRS)

    Holt, J. D.; Leavitt, L. D.; Bowen, H. D.

    1974-01-01

    Oculometer provides dynamic measurement of subject's look direction, and its outputs can be used to generate visual display of his look pattern and/or to cause equipment operation associated with his lookpoint at given times. Measured eye-direction information could be used as control input at man/machine interface.

  2. Dynamic Eye Model.

    ERIC Educational Resources Information Center

    Journal of Science and Mathematics Education in Southeast Asia, 1981

    1981-01-01

    Instructions (with diagrams and parts list) are provided for constructing an eye model with a pliable lens made from a plastic bottle which can vary its convexity to accommodate changing positions of an object being viewed. Also discusses concepts which the model can assist in developing. (Author/SK)

  3. The blind beautiful eye.

    PubMed

    Feinsod, M

    2000-03-01

    Master Jehan Yperman, a medieval surgeon, observed that when the optic nerve is injured, the eye becomes blind and beautiful. This is an attempt to trace the footsteps of this forgotten surgeon and to track the history of the cosmetic use of the belladonna herb, as well as the concept of amaurotic mydriasis.

  4. Through Students' Eyes.

    ERIC Educational Resources Information Center

    McLean-Donaldson, Karen B.

    1994-01-01

    Identifies how students perceive racism and its effects on student learning and whether antiracist/multicultural arts (ARMA) curricula can empower students to address racism in schools. Results show racism, through students' eyes, damages learning, attitudes, and behavior. ARMA positively effected students' ability to confront racism within their…

  5. Through Our Eyes

    ERIC Educational Resources Information Center

    Narva, Sara

    2009-01-01

    Through Our Eyes was a multimedia performance created in collaboration with the author's five modern dance students. Through video, sound, and dance, the piece shows some ways race has affected their lives. The author did not set out at the beginning of the semester to make this project in her dance class. It was born out of a hard conversation,…

  6. P gene as an inherited biomarker of human eye color.

    PubMed

    Rebbeck, Timothy R; Kanetsky, Peter A; Walker, Amy H; Holmes, Robin; Halpern, Allan C; Schuchter, Lynn M; Elder, David E; Guerry, DuPont

    2002-08-01

    Human pigmentation, including eye color, has been associated with skin cancer risk. The P gene is the human homologue to the mouse pink-eye dilution locus and is responsible for oculocutaneous albinism type 2 and other phenotypes that confer eye hypopigmentation. The P gene is located on chromosome 15q11.2-q12, which is also the location of a putative eye pigmentation gene (EYCL3) inferred to exist by linkage analysis. Therefore, the P gene is a strong candidate for determination of human eye color. Using a sample of 629 normally pigmented individuals, we found that individuals were less likely to have blue or gray eyes if they had P gene variants Arg305Trp (P = 0.002), Arg419Gln (P = 0.001), or the combination of both variants (P = 0.003). These results suggest that P gene, in part, determines normal phenotypic variation in human eye color and may therefore represent an inherited biomarker of cutaneous cancer risk.

  7. Corneal trauma from projection of metallic mercury into the eyes.

    PubMed

    Weber, F L; Babel, J

    1979-06-01

    A 24-year-old woman sustained bilateral ocular lesions due to projection of mercury into the eyes during an explosion in a chemical laboratory. A lamellar keratectomy was performed on the right eye four hours after the accident, and 12 days later, the same procedure was performed of the left eye. Studies by light and electron microscopy were done on both specimens. The essential findings were total loss of epithelium, necrosis of keratocytes, absence of inflammatory reaction, and absence of superficial stromal repair in the specimen that was obtained 12 days after the accident. These findings indirectly confirm the importance of epithelium and normally vascularized conjunctiva in healing wounds of the cornea.

  8. Acute Reversible Charles Bonnet Syndrome Following Eye Patch Placement.

    PubMed

    Nan, Lian; Yanbin, Hou; Jingping, Zhao

    2013-01-01

    Charles Bonnet syndrome (CBS) is characterised by recurrent vivid visual hallucinations in the presence of normal cognition. We present a case of CBS secondary to eye patching following Pars Plana Vitrectomy with an unusually acute onset in a 48-year-old woman. She presented with formed visual hallucinations that started less than 30 min after patching of her left eye. The patch was removed after 2 d, and these hallucinations persisted 2 d following eye patch removal. It is important that the ophthalmic surgeon be aware of the potential for development of CBS and offer appropriate referral and reassurance should it occur.

  9. Simple Solutions for Dry Eye

    MedlinePlus

    ... are more concentrated in the tear film of dry eye patients. In hot weather, sleep with the windows shut and keep cool with air conditioning. • Dry eye patients often develop or aggravate allergies. An ...

  10. Medicare Benefits and Your Eyes

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  11. Prevent Eye Injuries from Fireworks

    MedlinePlus

    ... Eye Emergencies How to Jump Start a Car Battery Safely Electronic Screens and Your Eyes Nutrition and ... External Resources The Cost of Vision Problems The Future of Vision Vision Problems in the U.S. Healthy ...

  12. Cerebral blood flow in normal and abnormal sleep and dreaming

    SciTech Connect

    Meyer, J.S.; Ishikawa, Y.; Hata, T.; Karacan, I.

    1987-07-01

    Measurements of regional or local cerebral blood flow (CBF) by the xenon-133 inhalation method and stable xenon computerized tomography CBF (CTCBF) method were made during relaxed wakefulness and different stages of REM and non-REM sleep in normal age-matched volunteers, narcoleptics, and sleep apneics. In the awake state, CBF values were reduced in both narcoleptics and sleep apneics in the brainstem and cerebellar regions. During sleep onset, whether REM or stage I-II, CBF values were paradoxically increased in narcoleptics but decreased severely in sleep apneics, while in normal volunteers they became diffusely but more moderately decreased. In REM sleep and dreaming CBF values greatly increased, particularly in right temporo-parietal regions in subjects experiencing both visual and auditory dreaming.

  13. Model-based dose calculations for COMS eye plaque brachytherapy using an anatomically realistic eye phantom

    SciTech Connect

    Lesperance, Marielle; Inglis-Whalen, M.; Thomson, R. M.

    2014-02-15

    simulation by up to 16%. In the full eye model simulations, the average dose to the lens is larger by 7%–9% than the dose to the center of the lens, and the maximum dose to the optic nerve is 17%–22% higher than the dose to the optic disk for all radionuclides. In general, when normalized to the same prescription dose at the tumor apex, doses delivered to all structures of interest in the full eye model are lowest for{sup 103}Pd and highest for {sup 131}Cs, except for the tumor where the average dose is highest for {sup 103}Pd and lowest for {sup 131}Cs. Conclusions : The eye is not radiologically water-equivalent, as doses from simulations of the plaque in the full eye model differ considerably from doses for the plaque in a water phantom and from simulated TG-43 calculated doses. This demonstrates the importance of model-based dose calculations for eye plaque brachytherapy, for which accurate elemental compositions of ocular media are necessary.

  14. Shrimps that pay attention: saccadic eye movements in stomatopod crustaceans.

    PubMed

    Marshall, N J; Land, M F; Cronin, T W

    2014-01-01

    Discovering that a shrimp can flick its eyes over to a fish and follow up by tracking it or flicking back to observe something else implies a 'primate-like' awareness of the immediate environment that we do not normally associate with crustaceans. For several reasons, stomatopods (mantis shrimp) do not fit the general mould of their subphylum, and here we add saccadic, acquisitional eye movements to their repertoire of unusual visual capabilities. Optically, their apposition compound eyes contain an area of heightened acuity, in some ways similar to the fovea of vertebrate eyes. Using rapid eye movements of up to several hundred degrees per second, objects of interest are placed under the scrutiny of this area. While other arthropod species, including insects and spiders, are known to possess and use acute zones in similar saccadic gaze relocations, stomatopods are the only crustacean known with such abilities. Differences among species exist, generally reflecting both the eye size and lifestyle of the animal, with the larger-eyed more sedentary species producing slower saccades than the smaller-eyed, more active species. Possessing the ability to rapidly look at and assess objects is ecologically important for mantis shrimps, as their lifestyle is, by any standards, fast, furious and deadly.

  15. Shrimps that pay attention: saccadic eye movements in stomatopod crustaceans

    PubMed Central

    Marshall, N. J.; Land, M. F.; Cronin, T. W.

    2014-01-01

    Discovering that a shrimp can flick its eyes over to a fish and follow up by tracking it or flicking back to observe something else implies a ‘primate-like’ awareness of the immediate environment that we do not normally associate with crustaceans. For several reasons, stomatopods (mantis shrimp) do not fit the general mould of their subphylum, and here we add saccadic, acquisitional eye movements to their repertoire of unusual visual capabilities. Optically, their apposition compound eyes contain an area of heightened acuity, in some ways similar to the fovea of vertebrate eyes. Using rapid eye movements of up to several hundred degrees per second, objects of interest are placed under the scrutiny of this area. While other arthropod species, including insects and spiders, are known to possess and use acute zones in similar saccadic gaze relocations, stomatopods are the only crustacean known with such abilities. Differences among species exist, generally reflecting both the eye size and lifestyle of the animal, with the larger-eyed more sedentary species producing slower saccades than the smaller-eyed, more active species. Possessing the ability to rapidly look at and assess objects is ecologically important for mantis shrimps, as their lifestyle is, by any standards, fast, furious and deadly. PMID:24395969

  16. Normal and abnormal lid function.

    PubMed

    Rucker, Janet C

    2011-01-01

    This chapter on lid function is comprised of two primary sections, the first on normal eyelid anatomy, neurological innervation, and physiology, and the second on abnormal eyelid function in disease states. The eyelids serve several important ocular functions, the primary objectives of which are protection of the anterior globe from injury and maintenance of the ocular tear film. Typical eyelid behaviors to perform these functions include blinking (voluntary, spontaneous, or reflexive), voluntary eye closure (gentle or forced), partial lid lowering during squinting, normal lid retraction during emotional states such as surprise or fear (startle reflex), and coordination of lid movements with vertical eye movements for maximal eye protection. Detailed description of the neurological innervation patterns and neurophysiology of each of these lid behaviors is provided. Abnormal lid function is divided by conditions resulting in excessive lid closure (cerebral ptosis, apraxia of lid opening, blepharospasm, oculomotor palsy, Horner's syndrome, myasthenia gravis, and mechanical) and those resulting in excessive lid opening (midbrain lid retraction, facial nerve palsy, and lid retraction due to orbital disease).

  17. Experiments on a Model Eye

    ERIC Educational Resources Information Center

    Arell, Antti; Kolari, Samuli

    1978-01-01

    Explains a laboratory experiment dealing with the optical features of the human eye. Shows how to measure the magnification of the retina and the refractive anomaly of the eye could be used to measure the refractive power of the observer's eye. (GA)

  18. LIMNOLOGICAL OPTOMETRY: EXAMINING EARTH'S EYE

    EPA Science Inventory

    In Thoreau's Walden, a lake is described as the landscape's most expressive feature and the earth's eye. Collectively, scientists are charged by society to assess, monitor, and remedy maladies of earth's eye in the same way optometrists maintain the health of the human eye. This ...

  19. How the Human Eye Focuses.

    ERIC Educational Resources Information Center

    Koretz, Jane F.; Handelman, George H.

    1988-01-01

    Describes the decline in people's ability to focus their eyes as their age increases. Discusses probable causes of this effect including changes in the eye's geometry and biochemistry. Diagrammatically illustrates age related changes in the lens of the human eye. (CW)

  20. Reconstructing the eyes of Urbilateria.

    PubMed Central

    Arendt, D; Wittbrodt, J

    2001-01-01

    The shared roles of Pax6 and Six homologues in the eye development of various bilaterians suggest that Urbilateria, the common ancestors of all Bilateria, already possessed some simple form of eyes. Here, we re-address the homology of bilaterian cerebral eyes at the level of eye anatomy, of eye-constituting cell types and of phototransductory molecules. The most widespread eye type found in Bilateria are the larval pigment-cup eyes located to the left and right of the apical organ in primary, ciliary larvae of Protostomia and Deuterostomia. They can be as simple as comprising a single pigment cell and a single photoreceptor cell in inverse orientation. Another more elaborate type of cerebral pigment-cup eyes with an everse arrangement of photoreceptor cells is found in adult Protostomia. Both inverse larval and everse adult eyes employ rhabdomeric photoreceptor cells and thus differ from the chordate cerebral eyes with ciliary photoreceptors. This is highly significant because on the molecular level we find that for phototransduction rhabdomeric versus ciliary photoreceptor cells employ divergent rhodopsins and non-orthologous G-proteins, rhodopsin kinases and arrestins. Our comparison supports homology of cerebral eyes in Protostomia; it challenges, however, homology of chordate and non-chordate cerebral eyes that employ photoreceptor cells with non-orthologous phototransductory cascades. PMID:11604122

  1. ADAPTIVE EYE MODEL - Poster Paper

    NASA Astrophysics Data System (ADS)

    Galetskiy, Sergey O.; Kudryashov, Alexey V.

    2008-01-01

    We propose experimental adaptive eye model based on flexible 18-electrode bimorph mirror reproducing human eye aberrations up to 4th radial order of Zernike polynomials at frequency of 10Hz. The accuracy of aberrations reproduction in most cases is better than λ/10 RMS. The model is introduced to aberrometer for human eye aberrations compensation to improve visual acuity test.

  2. Scan of the back of human eye

    NASA Technical Reports Server (NTRS)

    2003-01-01

    ProVision Technologies, a NASA commercial space center at Sternis Space Center in Mississippi, has developed a new hyperspectral imaging (HSI) system that is much smaller than the original large units used aboard remote sensing aircraft and satellites. The new apparatus is about the size of a breadbox. HSI may be useful to ophthalmologists to study and diagnose eye health, both on Earth and in space, by examining the back of the eye to determine oxygen and blood flow quickly and without any invasion. ProVision's hyperspectral imaging system can scan the human eye and produce a graph showing optical density or light absorption, which can then be compared to a graph from a normal eye. Scans of the macula, optic disk or optic nerve head, and blood vessels can be used to detect anomalies and identify diseases in this delicate and important organ. ProVision has already developed a relationship with the University of Alabama at Birmingham, but is still on the lookout for a commercial partner in this application.

  3. Lens coloboma in one eye and ectopia lentis in the other eye of a patient with Marfan syndrome.

    PubMed

    Thapa, Bikram Bahadur; Singh, Ramandeep; Ram, Jagat; Kumar, Abiraj

    2014-12-09

    We present a case of Marfan syndrome with lens coloboma in one eye and ectopia lentis in the other. A 14-year-old girl reported decreased vision in the left eye. Her visual acuity was 6/24 and counting fingers at 1 m in the right and left eyes, respectively. Her intraocular pressure was 15 mm Hg in both eyes. Evaluation of the right eye on slit lamp biomicroscopy under mydriasis revealed an inferiorly visible flattened and concave crystalline lens equator from 4 to 8 o'clock position along with notching and absence of zonules, suggestive of lens coloboma. Left eye examination revealed a superiorly subluxated lens from 3 to 9 o'clock position and posterior subcapsular cataract. The posterior segment evaluation of both eyes was normal. Her father, aunt and grandfather were of tall stature, characteristic of Marfan syndrome. On systemic evaluation, the patient was diagnosed as Marfan syndrome. After surgical correction she achieved vision of 6/6 in both eyes.

  4. Diagnosis of mild Alzheimer disease through the analysis of eye movements during reading.

    PubMed

    Fernández, Gerardo; Castro, Liliana R; Schumacher, Marcela; Agamennoni, Osvaldo E

    2015-03-01

    Reading requires the integration of several central cognitive subsystems, ranging from attention and oculomotor control to word identification and language comprehension. Reading saccades and fixations contain information that can be correlated with word properties. When reading a sentence, the brain must decide where to direct the next saccade according to what has been read up to the actual fixation. In this process, the retrieval memory brings information about the current word features and attributes into working memory. According to this information, the prefrontal cortex predicts and triggers the next saccade. The frequency and cloze predictability of the fixated word, the preceding words and the upcoming ones affect when and where the eyes will move next. In this paper we present a diagnostic technique for early stage cognitive impairment detection by analyzing eye movements during reading proverbs. We performed a case-control study involving 20 patients with probable Alzheimer's disease and 40 age-matched, healthy control patients. The measurements were analyzed using linear mixed-effects models, revealing that eye movement behavior while reading can provide valuable information about whether a person is cognitively impaired. To the best of our knowledge, this is the first study using word-based properties, proverbs and linear mixed-effect models for identifying cognitive abnormalities.

  5. Narrative comprehension and production in children with SLI: An eye movement study

    PubMed Central

    ANDREU, LLORENÇ; SANZ-TORRENT, MONICA; OLMOS, JOAN GUÀRDIA; MACWHINNEY, BRIAN

    2014-01-01

    This study investigates narrative comprehension and production in children with specific language impairment (SLI). Twelve children with SLI (mean age 5; 8 years) and 12 typically developing children (mean age 5; 6 years) participated in an eye-tracking experiment designed to investigate online narrative comprehension and production in Catalan- and Spanish-speaking children with SLI. The comprehension task involved the recording of eye movements during the visual exploration of successive scenes in a story, while listening to the associated narrative. With regard to production, the children were asked to retell the story, while once again looking at the scenes, as their eye movements were monitored. During narrative production, children with SLI look at the most semantically relevant areas of the scenes fewer times than their age-matched controls, but no differences were found in narrative comprehension. Moreover, the analyses of speech productions revealed that children with SLI retained less information and made more semantic and syntactic errors during retelling. Implications for theories that characterize SLI are discussed. PMID:21453036

  6. Eye lens dosimetry in anesthesiology: a prospective study.

    PubMed

    Vaes, Bart; Van Keer, Karel; Struelens, Lara; Schoonjans, Werner; Nijs, Ivo; Vandevenne, Jan; Van Poucke, Sven

    2017-04-01

    The eye lens is one of the most sensitive organs for radiation injury and exposure might lead to radiation induced cataract. Eye lens dosimetry in anesthesiology has been published in few clinical trials and an active debate about the causality of radiation induced cataract is still ongoing. Recently, the International Commission on Radiological Protection (ICRP) recommended a reduction in the annual dose limit for occupational exposure for the lens of the eye from 150 to 20 mSv, averaged over a period of 5 years, with the dose in a single year not exceeding 50 mSv. This prospective study investigated eye lens dosimetry in anesthesiology practice during a routine year of professional activity. The radiation exposure measured represented the exposure in a normal working schedule of a random anesthesiologist during 1 month and this cumulative eye lens dose was extrapolated to 1 year. Next, eye lens doses were measured in anesthesiology during neuro-embolisation procedures, radiofrequency ablations or vertebroplasty/kyphoplasty procedures. The eye lens doses are measured in terms of the dose equivalent H p(3) with the Eye-D dosimeter (Radcard, Poland) close to the right eye (on the temple). In 16 anesthesiologists, the estimated annual eye lens doses range from a minimum of 0.4 mSv to a maximum of 3.5 mSv with an average dose of 1.33 mSv. Next, eye lens doses were measured for nine neuro-embolisation procedures, ten radiofrequency ablations and six vertebroplasty/kyphoplasty procedures. Average eye lens doses of 77 ± 76 µSv for neuro-embolisations, 38 ± 34 µSv for cardiac ablations and 40 ± 44 µSv for vertebro-/kyphoplasty procedures were recorded. The maximum doses were respectively 264, 97 and 122 µSv. This study demonstrated that the estimated annual eye lens dose is well below the revised ICRP's limit of 20 mSv/year. However, we demonstrated high maximum and average doses during neuro-embolisation, cardiac ablation and vertebro

  7. Eye and head motion during head turns in spaceflight

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Uri, John J.; Moore, Thomas P.; Pool, Sam L.

    1988-01-01

    Eye-head motion was studied pre-, in- and postflight during single voluntary head turns. A transient increase in vestibulo-ocular reflex (VOR) gain occurred early in the flight, but later trended toward normal. This increased gain was produced by a relative increase in eye counterrotation velocity. Asymmetries in gain with right and left turns also occurred, caused by asymmetries in eye counterrotation velocities. These findings were remarkably similar to those from Soviet primate studies using gaze fixation targets, except the human study trended more rapidly toward normal. These findings differ substantially from those measuring VOR gain by head oscillation, in which no significant changes were found inflight. No visual disturbances were noted in either test condition or in normal activities. These head turn studies are the only ones to date documenting any functional change in VOR in weightlessness.

  8. An Eye on Trafficking Genes: Identification of Four Eye Color Mutations in Drosophila

    PubMed Central

    Grant, Paaqua; Maga, Tara; Loshakov, Anna; Singhal, Rishi; Wali, Aminah; Nwankwo, Jennifer; Baron, Kaitlin; Johnson, Diana

    2016-01-01

    Genes that code for proteins involved in organelle biogenesis and intracellular trafficking produce products that are critical in normal cell function . Conserved orthologs of these are present in most or all eukaryotes, including Drosophila melanogaster. Some of these genes were originally identified as eye color mutants with decreases in both types of pigments found in the fly eye. These criteria were used for identification of such genes, four eye color mutations that are not annotated in the genome sequence: chocolate, maroon, mahogany, and red Malpighian tubules were molecularly mapped and their genome sequences have been evaluated. Mapping was performed using deletion analysis and complementation tests. chocolate is an allele of the VhaAC39-1 gene, which is an ortholog of the Vacuolar H+ ATPase AC39 subunit 1. maroon corresponds to the Vps16A gene and its product is part of the HOPS complex, which participates in transport and organelle fusion. red Malpighian tubule is the CG12207 gene, which encodes a protein of unknown function that includes a LysM domain. mahogany is the CG13646 gene, which is predicted to be an amino acid transporter. The strategy of identifying eye color genes based on perturbations in quantities of both types of eye color pigments has proven useful in identifying proteins involved in trafficking and biogenesis of lysosome-related organelles. Mutants of these genes can form the basis of valuable in vivo models to understand these processes. PMID:27558665

  9. An Eye on Trafficking Genes: Identification of Four Eye Color Mutations in Drosophila.

    PubMed

    Grant, Paaqua; Maga, Tara; Loshakov, Anna; Singhal, Rishi; Wali, Aminah; Nwankwo, Jennifer; Baron, Kaitlin; Johnson, Diana

    2016-10-13

    Genes that code for proteins involved in organelle biogenesis and intracellular trafficking produce products that are critical in normal cell function . Conserved orthologs of these are present in most or all eukaryotes, including Drosophila melanogaster Some of these genes were originally identified as eye color mutants with decreases in both types of pigments found in the fly eye. These criteria were used for identification of such genes, four eye color mutations that are not annotated in the genome sequence: chocolate, maroon, mahogany, and red Malpighian tubules were molecularly mapped and their genome sequences have been evaluated. Mapping was performed using deletion analysis and complementation tests. chocolate is an allele of the VhaAC39-1 gene, which is an ortholog of the Vacuolar H(+) ATPase AC39 subunit 1. maroon corresponds to the Vps16A gene and its product is part of the HOPS complex, which participates in transport and organelle fusion. red Malpighian tubule is the CG12207 gene, which encodes a protein of unknown function that includes a LysM domain. mahogany is the CG13646 gene, which is predicted to be an amino acid transporter. The strategy of identifying eye color genes based on perturbations in quantities of both types of eye color pigments has proven useful in identifying proteins involved in trafficking and biogenesis of lysosome-related organelles. Mutants of these genes can form the basis of valuable in vivo models to understand these processes.

  10. Eye movement abnormalities.

    PubMed

    Moncayo, Jorge; Bogousslavsky, Julien

    2012-01-01

    Generation and control of eye movements requires the participation of the cortex, basal ganglia, cerebellum and brainstem. The signals of this complex neural network finally converge on the ocular motoneurons of the brainstem. Infarct or hemorrhage at any level of the oculomotor system (though more frequent in the brain-stem) may give rise to a broad spectrum of eye movement abnormalities (EMAs). Consequently, neurologists and particularly stroke neurologists are routinely confronted with EMAs, some of which may be overlooked in the acute stroke setting and others that, when recognized, may have a high localizing value. The most complex EMAs are due to midbrain stroke. Horizontal gaze disorders, some of them manifesting unusual patterns, may occur in pontine stroke. Distinct varieties of nystagmus occur in cerebellar and medullary stroke. This review summarizes the most representative EMAs from the supratentorial level to the brainstem.

  11. Ultrasonographic anatomy of the bovine eye.

    PubMed

    Potter, Timothy J; Hallowell, Gayle D; Bowen, I Mark

    2008-01-01

    The purposes of the study were to describe the ultrasonographic appearance and measurements of the normal bovine eye, to compare the measurements to those reported previously for cadaveric eyes and to describe differences between ocular dimensions of Holstein Friesian and Jersey cattle. Sixty transpalpebral ocular ultrasonographic examinations were performed on 30 adult Holstein Friesian cows, and 16 examinations were performed on 8 adult Jersey cows. Transpalpebral ultrasonographic images were obtained with a 10 MHz linear transducer in both horizontal and vertical imaging planes. The ultrasonographic appearance of structures within the bovine eye is similar to that in other species, although the ciliary artery was frequently identified, appearing as a 0.33 +/- 0.04 cm diameter hypoechoic area. The axial length of the globe was significantly greater in Holstein Friesian cattle (3.46 +/- 0.09 cm) compared with Jersey cattle (3.27 +/- 0.19 cm; P = 0.001), although the vitreous depth was smaller in Holstein Friesian cattle (1.46 +/- 0.09 cm) (P = 0.0009). The anterioposterior depth of the lens was significantly greater in Jersey cattle (1.92 +/- 0.11 cm) and the cornea was thinner in Jersey cattle (0.17 +/- 0.02 cm). The appearance and ocular distances for live animals were similar to those reported previously for cadaveric specimens. The knowledge of normal ocular dimensions facilitates the use of ultrasonography in the evaluation of ocular disease in cattle.

  12. Schizophrenia and the eye

    PubMed Central

    Silverstein, Steven M.; Rosen, Richard

    2015-01-01

    Although visual processing impairments are common in schizophrenia, it is not clear to what extent these originate in the eye vs. the brain. This review highlights potential contributions, from the retina and other structures of the eye, tovisual processing impairments in schizophrenia and high-risk states. A second goal is to evaluate the status of retinal abnormalities as biomarkers for schizophrenia. The review was motivated by known retinal changes in other disorders (e.g., Parkinson's disease, multiple sclerosis), and their relationships to perceptual and cognitive impairments, and disease progression therein. The evidence reviewed suggests two major conclusions. One is that there are multiple structural and functional disturbances of the eye in schizophrenia, all of which could be factors in the visual disturbances of patients. These include retinal venule widening, retinal nerve fiber layer thinning, dopaminergic abnormalities, abnormal ouput of retinal cells as measured by electroretinography (ERG), maculopathies and retinopathies, cataracts, poor acuity, and strabismus. Some of these are likely to be illness-related, whereas others may be due to medication or comorbid conditions. The second conclusion is that certain retinal findings can serve as biomarkers of neural pathology, and disease progression, in schizophrenia. The strongest evidence for this to date involves findings of widened retinal venules, thinning of the retinal nerve fiber layer, and abnormal ERG amplitudes. These data suggest that a greater understanding of the contribution of retinal and other ocular pathology to the visual and cognitive disturbances of schizophrenia is warranted, and that retinal changes have untapped clinical utility. PMID:26345525

  13. Comprehensive eye evaluation algorithm

    NASA Astrophysics Data System (ADS)

    Agurto, C.; Nemeth, S.; Zamora, G.; Vahtel, M.; Soliz, P.; Barriga, S.

    2016-03-01

    In recent years, several research groups have developed automatic algorithms to detect diabetic retinopathy (DR) in individuals with diabetes (DM), using digital retinal images. Studies have indicated that diabetics have 1.5 times the annual risk of developing primary open angle glaucoma (POAG) as do people without DM. Moreover, DM patients have 1.8 times the risk for age-related macular degeneration (AMD). Although numerous investigators are developing automatic DR detection algorithms, there have been few successful efforts to create an automatic algorithm that can detect other ocular diseases, such as POAG and AMD. Consequently, our aim in the current study was to develop a comprehensive eye evaluation algorithm that not only detects DR in retinal images, but also automatically identifies glaucoma suspects and AMD by integrating other personal medical information with the retinal features. The proposed system is fully automatic and provides the likelihood of each of the three eye disease. The system was evaluated in two datasets of 104 and 88 diabetic cases. For each eye, we used two non-mydriatic digital color fundus photographs (macula and optic disc centered) and, when available, information about age, duration of diabetes, cataracts, hypertension, gender, and laboratory data. Our results show that the combination of multimodal features can increase the AUC by up to 5%, 7%, and 8% in the detection of AMD, DR, and glaucoma respectively. Marked improvement was achieved when laboratory results were combined with retinal image features.

  14. Perspectives on eye development.

    PubMed

    Fini, M E; Strissel, K J; West-Mays, J A

    1997-01-01

    The lens of the vertebrate eye was the classic model used to demonstrate the concepts of inductive interactions controlling development. However, it is in the Drosophila model that the greatest progress in understanding molecular mechanisms of eye development have most recently been mode. This progress can be attributed to the power of molecular genetics, an approach that was once confined to simpler systems like worms and flies, but is now becoming possible in vertebrates. Thus, the use of transgenic and knock-out gene technology, coupled with the availability of new positional cloning methods, has recently initiated a surge of progress in the mouse genetic model and has also led to the identification of genes involved in human inherited disorders. In addition, gene transfer techniques have opened up opportunities for progress using chick, Xenopus, and other classic developmental systems. Finally, a new vertebrate genetic model, zebrafish, appears very promising for molecular studies. As a result of the opportunities presented by these new approaches, eye development has come into the limelight, hence the timeliness of this focus issue of Developmental Genetics. In this introductory review, we discuss three areas of current work arising through the use of these newer genetic approaches, and pertinent to research articles presented herein. We also touch on related studies reported at the first Keystone Meeting on Ocular Cell and Molecular Biology, recently held in Tamarron Springs, Colorado, January 7-12, 1997.

  15. 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

  16. Intraocular eyelashes and iris cyst in anterior chamber following penetrating eye injury: a case report

    PubMed Central

    Sahu, Sabin; Puri, Lila Raj; Singh, Sanjay Kumar

    2017-01-01

    Background The presence of intraocular eyelashes following penetrating eye injury or ocular surgery is relatively uncommon. The response of the eye to intraocular eyelashes is variable. The eyelash may be symptomatic or may remain asymptomatic for long periods. Objective We report a case with two intraocular eyelashes and an iris cyst after 2 years of asymptomatic period following penetrating eye injury. Case presentation A 24-year-old male presented with decreased vision in the left eye which he had noticed for the previous 2 weeks. His visual acuity was 6/6 in the right eye and 6/18 in the left eye, improving to 6/9 with -2.5 DC × 140° correction. The intraocular pressure was 12 mmHg in both eyes. On slit-lamp examination, the left eye showed 8 mm linear peripheral corneal opacity nasally, two eyelashes in the superior anterior chamber, and an iris cyst measuring 4 mm × 4 mm in the superior iris. The right eye was normal. Dilated fundus examination of both eyes was normal. The eyelashes and cyst were removed surgically. There were no complications during the 3-month follow-up period. Conclusion Intraocular implantation of eyelashes following penetrating eye injury can remain asymptomatic for long periods; however, late development of iris cyst may occur. PMID:28356777

  17. Discordant Dry Eye Disease (An American Ophthalmological Society Thesis)

    PubMed Central

    Shtein, Roni M.; Harper, Daniel E.; Pallazola, Vincent; Harte, Steven E.; Hussain, Munira; Sugar, Alan; Williams, David A.; Clauw, Daniel J.

    2016-01-01

    Purpose To improve understanding of dry eye disease and highlight a subgroup of patients who have a component of central sensitization and neuropathic pain contributing to their condition. Methods Prospective, cross-sectional, IRB-approved study comparing isolated dry eye disease (n=48) to fibromyalgia (positive control; n=23) and healthy (negative control; n=26) individuals with ocular surface examination, corneal confocal microscopy, quantitative sensory testing, and self-reported ocular symptoms and systemic associations. A subset of patients also underwent skin biopsy and/or brain neuroimaging. Dry eye patients were split into concordant (ie, those with dry eyes on examination) and discordant (ie, those with dry eye symptoms but normal examination) subgroups for further analysis. We hypothesized that on the systemic measures included, concordant patients would resemble healthy controls, whereas discordant patients would show evidence of centralized mechanisms similar to fibromyalgia. Results Schirmer test and Ocular Surface Disease Index (OSDI) scores indicated significant decreases in tear production (Schirmer: healthy, 18.5±8.2 mm; dry, 11.2±5.4 mm; fibromyalgia, 14.4±7.5; P<.001) and increases in self-reported dry eye symptoms (OSDI: healthy, 1.9±3.0; dry, 20.3±17.7; fibromyalgia, 20.3±17.1; P<.001) in the dry eye and fibromyalgia patients, compared to controls. The discordant subgroup had decreased corneal nerve density and decreased visual quality-of-life scores, similar to patients with fibromyalgia. Concordant patients were more similar to healthy controls on these measures. Conclusions Individuals with discordant dry eye may have a central pathophysiologic mechanism leading to their eye pain symptoms, which could be an important factor to consider in treatment of chronic idiopathic dry eye. PMID:28050051

  18. Dry Eye as a Mucosal Autoimmune Disease

    PubMed Central

    Stern, Michael E.; Schaumburg, Chris S.; Pflugfelder, Stephen C.

    2013-01-01

    Dry eye is a common ocular surface inflammatory disease that significantly affects quality of life. Dysfunction of the lacrimal function unit (LFU) alters tear composition and breaks ocular surface homeostasis, facilitating chronic inflammation and tissue damage. Accordingly, the most effective treatments to date are geared towards reducing inflammation and restoring normal tear film. The pathogenic role of CD4+ T cells is well known, and the field is rapidly realizing the complexity of other innate and adaptive immune factors involved in the development and progression of disease. The data support the hypothesis that dry eye is a localized autoimmune disease originating from an imbalance in the protective immunoregulatory and proinflammatory pathways of the ocular surface. PMID:23360156

  19. Eye Movements Reveal Hierarchical Motion Processing

    NASA Technical Reports Server (NTRS)

    Mulligan, Jeffrey B.; Null, Cynthia H. (Technical Monitor)

    1996-01-01

    Purpose: In the analysis of visual motion, local features such as orientation are analyzed early in the cortical processing stream (V1), while integration across orientation and space is thought to occur in higher cortical areas such as MT, MST, etc. If all areas provide inputs to eye movement control centers, we would expect that local properties would drive eye movements with relatively short latencies, while global properties would require longer latencies. When such latencies are observed, they can provide information about when (and where?) various stimulus properties are analyzed. Methods: The stimulus employed was an elliptical Gabor patch with a drifting carrier, in which the orientations of the carrier grating and the contrast window were varied independently. We have previously demonstrated that the directional percepts evoked by this stimulus vary between the "grating direction" (the normal to the grating's orientation) and the "window direction", and that similar effects can be observed in reflexive eye movements. Subjects viewed such a stimulus while attempting to maintain steady fixation on the center of the pattern, and the small reflexive eye movements ("stare OKN") were recorded. In the middle of the trial, the orientation of either the grating or the window was rotated smoothly by 30 degrees. Results: Responses to the shift of both grating orientation and window orientation are seen in the average OKN slow phase velocity. Grating rotations produce a rapid OKN rotation to the grating direction (100 ms latency, 300 ms time constant), followed by a slower rebound to the steady state perceived direction midway between the grating and window directions. Window rotations, on the other hand, evoke a slower response (200 ms latency, 500 ms time constant). Conclusions: The results demonstrate multiple cortical inputs to eye movement control: a fast, early input driven by orientation, and a slower input from higher areas sensitive to global stimulus

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

    PubMed

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

    2014-08-15

    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.

  1. Autofluorescence spectroscopy for early diagnosis of cancer eye

    NASA Astrophysics Data System (ADS)

    Majumder, Shovan K.; Ghosh, Nirmalya; Rathod, Sopan M.; Gupta, Pradeep K.

    2007-02-01

    We report an in-vitro autofluorescence spectroscopic study of cow eye tissue to explore the applicability of the approach in discriminating early stage "cancer eye" from normal squamous eye tissues. Significant differences were observed in the autofluorescence signatures between the "cancer eye" and normal eye tissues. The spectral differences were quantified by employing a probability-based diagnostic algorithm developed based on recently formulated theory of Relevance Vector Machine (RVM), a Bayesian machine-learning framework of statistical pattern recognition. The algorithm provided sensitivity and specificity values of 97 +/- 2% towards cancer for the training set data based on leave-one-out cross validation and a sensitivity of 97 +/- 2% and a specificity of 99 +/- 1% towards cancer for the independent validation set data. These results suggest that autofluorescence spectroscopy might prove to be a quantitative in-vivo diagnostic modality for early and accurate diagnosis of "cancer eye" in veterinary clinical setting, which would help improve ranch management from both economic and animal care standpoint.

  2. Intensive Care Nurses' Views and Practices for Eye Care: An International Comparison.

    PubMed

    Güler, Elem Kocaçal; Eşer, İsmet; Fashafsheh, Imad Hussein Deeb

    2016-02-18

    Eye care is an important area of critical care. However, lack of eye care studies is a common issue across the globe. The aim of this study is to determine the views and practices of intensive care unit (ICU) nurses on eye care in Turkey and Palestine. This descriptive study was conducted using a self-administrated questionnaire. The data were collected from 111 nurses in nine kinds of ICUs in two education hospital. Normal saline (75.9%) was the most commonly reported solution for eye hygiene among the Palestinian nurses, and gauze soaked in normal saline or sterile water (64.3%) were the most frequently used supplies by the Turkish nurses. Although both Palestinian and Turkish ICU nurses took some precautions to prevent eye complications in critical patients, there were some gaps and insufficiencies in the eye care of ICU patients. There is a need for continuing training in this area.

  3. Comparison of optical coherence tomography findings in a patient with central retinal artery occlusion in one eye and end-stage glaucoma in the fellow eye.

    PubMed

    Greene, Daniel P; Richards, Charles P; Ghazi, Nicola G

    2012-01-01

    This case describes a patient with chronic central retinal artery occlusion in one eye and end-stage traumatic glaucoma in the fellow eye. Optical coherence tomography (OCT) of the macula of the chronic phase of central retinal artery occlusion of the right eye indicated loss of the normal foveal depression, extensive inner retinal atrophy, and marked retinal thinning. In contrast, scans of the left eye with end-stage glaucoma demonstrated an intact foveal depression and limited retinal thinning. The pattern of macular OCT findings in this patient illustrates distinguishing features between chronic central retinal artery occlusion and chronic optic neuropathy due to end-stage glaucoma.

  4. Occupational cow horn eye injuries in ibadan, Nigeria.

    PubMed

    Ibrahim, Oa; Olusanya, Ba

    2014-11-01

    This case series aims to describe the clinical features, management, and outcome of occupational eye injuries caused by cow horns and to recommend possible preventive measures. A review of patients with cow horn inflicted eye injuries seen at the University College Hospital, Ibadan between January 2006, and December 2011 was conducted. Three patients were identified, and their charts were reviewed for demographic information, mechanism of injury, initial and final visual acuity, surgeries performed, as well as anatomic and visual outcome. The three patients were males and were aged 45, 22, and 49 years, respectively. They were all involved in cattle-related jobs, and they all had unilateral open-globe injuries with corneoscleral lacerations. Presenting visual acuity was nil light perception in the injured eyes. The contralateral eyes were all normal. Two of the patients required evisceration of the eye, while the third patient underwent repair of lacerations. Visual improvement was not achieved in any of the patients. Cow horn eye injuries may be quite severe and could result in loss of the eye with monocular blindness. Careful attention must be paid to prevent such injuries. Cattle rearers and dealers should wear safety goggles, and proper restraint of the animals is advocated.

  5. FRACTIONATION OF THE EYE PIGMENTS OF DROSOPHILA MELANOGASTER.

    PubMed

    Wald, G; Allen, G

    1946-09-20

    Eye pigments of normal and mutant types of D. melanogaster have been extracted with water and fractionated by chromatographic adsorption on powdered talc. Spectra of all the fractions obtainable in solution have been measured and the general chemical behavior of the pigments is described. Two chemically distinct groups of pigments are found, to be identified with the earlier designated red and brown components. The red component in the wild-type eye contains three well defined pigments, two of them capable of further subdivision so that the total number of fractions obtained is five. There is also present a brown component pigment which could not be treated quantitatively by the methods employed. All members of the wild-type red component are found in cinnabar eyes, unaccompanied by the brown component. Conversely, brown eyes contain a pigment indistinguishable from the wild-type brown component, virtually alone. In sepia eyes, one red component and two brown component pigments can be distinguished, all three pigments differing from those of wild-type eyes. Pigments apparently identical with those found in wild-type melanogaster eyes have also been found in D. virilis.

  6. The potential role of neuropathic mechanisms in dry eye syndromes.

    PubMed

    Mcmonnies, Charles W

    Dry eye syndromes can involve both nociceptive and neuropathic symptoms. Nociceptive symptoms are the normal physiological responses to noxious stimuli. Neuropathic symptoms are caused by a lesion or disease of the somatosensory nervous system and can be the result of hypersensitisation of peripheral or central corneal and conjunctival somatosensory nerves. For example, inflammation could induce neuroplastic peripheral sensitisation of the ocular surface or lid wiper and exacerbate nociceptive symptoms. Neuropathic symptoms may explain the incommensurate relation between signs and symptoms in some dry eye syndromes although absence of signs of a dry eye syndrome may also be a consequence of inappropriate methods used when examining for them. Involvement of neuropathic mechanisms may also help explain dry eye symptoms which occur in association with reduced corneal sensitivity. This review includes a discussion of the potential for ocular symptoms involving neuropathic mechanisms to contribute to psychosocial problems such as depression, stress, anxiety and sleep disorders as well as for these types of psychosocial problems to contribute to neuropathic mechanisms and dry eye syndromes. Failure to consider the possibility that neuropathic mechanisms can contribute to dry eye syndromes may reduce accuracy of diagnosis and the suitability of treatment provided. Dry eye symptoms in the absence of commensurate evidence of tear dysfunction, and unsatisfactory response to tear dysfunction therapies should prompt consideration of neuropathic mechanisms being involved. Symptoms which persist after local anaesthetic instillation are more likely to be neuropathic in origin. Reducing inflammation may help limit any associated neuroplastic hypersensitivity.

  7. In vivo laser-induced breakdown in the rabbit eye

    NASA Astrophysics Data System (ADS)

    Cain, Clarence P.; DiCarlo, Cheryl D.; Kennedy, Paul K.; Noojin, Gary D.; Amnotte, Rodney E.; Roach, William P.

    1995-05-01

    Threshold measurements for femtosecond laser pulsewidths have been made for retinal minimum visible lesions (MVLs) in Dutch Belted rabbit and rhesus monkey eyes. Laser-induced breakdown (LIB) thresholds in biological materials including vitreous, normal saline, tap water, and ultrapure water have been measured and reported using an artificial eye. We have recorded on video the first LIB causing bubble formation in any eye in vivo using albino rabbit eyes (New Zealand white) with 120- femtosecond (fs) pulses and pulse energies as low as 5 microjoules ((mu) J). These bubbles were clearly formed anterior to the retina within the vitreous humor and, with 60 (mu) J of energy, they lasted for several seconds before disappearing and leaving no apparent damage to the retina. We believe this to be true LIB because of the lack of pigmentation or melanin granules within the albino rabbit eye (thus no absorptive elements) and because of the extremely high peak powers within the 5-(mu) J, 120-fs laser pulse. These high peak powers produce self-focusing of the pulse within the vitreous. The bubble formation at the breakdown site acts as a limiting mechanism for energy transmission and may explain why high-energy femotsecond pulses at energies up to 100 (mu) J sometimes do not cause severe damage in the pigmented rabbit eye. This fact may also explain why it is so difficult to produce hemorrhagic lesions in either the rabbit or primate eye with 100-fs laser pulses.

  8. Live Speech Driven Head-and-Eye Motion Generators.

    PubMed

    Le, Binh H; Ma, Xiaohan; Deng, Zhigang

    2012-11-01

    This paper describes a fully automated framework to generate realistic head motion, eye gaze, and eyelid motion simultaneously based on live (or recorded) speech input. Its central idea is to learn separate yet interrelated statistical models for each component (head motion, gaze, or eyelid motion) from a prerecorded facial motion data set: 1) Gaussian Mixture Models and gradient descent optimization algorithm are employed to generate head motion from speech features; 2) Nonlinear Dynamic Canonical Correlation Analysis model is used to synthesize eye gaze from head motion and speech features, and 3) nonnegative linear regression is used to model voluntary eye lid motion and log-normal distribution is used to describe involuntary eye blinks. Several user studies are conducted to evaluate the effectiveness of the proposed speech-driven head and eye motion generator using the well-established paired comparison methodology. Our evaluation results clearly show that this approach can significantly outperform the state-of-the-art head and eye motion generation algorithms. In addition, a novel mocap+video hybrid data acquisition technique is introduced to record high-fidelity head movement, eye gaze, and eyelid motion simultaneously.

  9. How to administer eye drops and eye ointment.

    PubMed

    Shaw, Mary

    2016-05-25

    Rationale and key points Eye drops and eye ointment are the mainstay of treatment of ocular conditions. Failure to prioritise administration of these medicines can prolong the condition and may present a risk to the patient's vision. ▶ Eye drops and eye ointments are used to treat acute and chronic conditions of the eye and surrounding structures. Eye drops must be instilled before applying eye ointment, since the ointment will affect the absorption of the eye drop. ▶ Nurses require knowledge of the technique, side effects and potential interactions associated with systemically or topically applied medicines to the eye to ensure patient safety and optimum outcomes. Reflective activity Clinical skills articles can help update your practice and ensure it remains evidence based. Apply this article to your practice. Reflect on and write a short account of: 1. How this article will change your practice. 2. How you intend to develop your knowledge and skills regarding treatment of ocular conditions. Subscribers can update their reflective accounts at rcni.com/portfolio.

  10. Estradiol levels in girls with Turner's syndrome compared to normal prepubertal girls as determined by an ultrasensitive assay.

    PubMed

    Wilson, Courtnay A; Heinrichs, Claudine; Larmore, Kimberly A; Craen, Marguerita; Brown-Dawson, Jacquelyn; Shaywitz, Sally; Ross, Judith; Klein, Karen Oerter

    2003-01-01

    Based on growing evidence that estradiol is produced in small amounts even in the prepubertal ovary, we hypothesized that estradiol levels in girls with Turner's syndrome (TS) are lower than in normal prepubertal girls secondary to the lack of normally functioning ovaries. Estradiol levels in untreated girls with TS have not been previously well defined because of the lack of adequate sensitivity of previously available estradiol assays. We utilized an ultrasensitive assay to study estradiol levels in 34 girls with TS and 34 normal age-matched prepubertal girls between the ages of 5 and 12 years. The average estradiol level in the girls with TS (6.4 +/- 4.9 pmol/l estradiol equivalents) was significantly lower than in the normal prepubertal girls (12.7 +/- 10.8 pmol/l estradiol equivalents; p < 0.01). Girls with TS were significantly shorter, and weighed less than the normal prepubertal girls, as expected. The estradiol level was not significantly correlated with height, bone age, or degree of bone age delay. In conclusion, girls with TS have significantly lower estradiol levels than normal age-matched prepubertal girls. This report is consistent with the hypothesis that the lack of normal ovarian function in girls with TS is evident even before puberty.

  11. Bilateral Glaucomatous Optic Neuropathy Caused by Eye Rubbing.

    PubMed

    Savastano, Alfonso; Savastano, Maria Cristina; Carlomusto, Laura; Savastano, Silvio

    2015-01-01

    In this report, we describe a particular condition of a 52-year-old man who showed advanced bilateral glaucomatous-like optic disc damage, even though the intraocular pressure resulted normal during all examinations performed. Visual field test, steady-state pattern electroretinogram, retinal nerve fiber layer and retinal tomographic evaluations were performed to evaluate the optic disc damage. Over a 4-year observational period, his visual acuity decreased to 12/20 in the right eye and counting fingers in the left eye. Visual fields were severely compromised, and intraocular pressure values were not superior to 14 mm Hg during routine examinations. An accurate anamnesis and the suspicion of this disease represent a crucial aspect to establish the correct diagnosis. In fact, our patient strongly rubbed his eyes for more than 10 h per day. Recurrent and continuous eye rubbing can induce progressive optic neuropathy, causing severe visual field damage similar to the pathology of advanced glaucoma.

  12. Directional eye fixation sensor using birefringence-based foveal detection

    NASA Astrophysics Data System (ADS)

    Gramatikov, Boris I.; Zalloum, Othman H. Y.; Wu, Yi Kai; Hunter, David G.; Guyton, David L.

    2007-04-01

    We recently developed and reported an eye fixation monitor that detects the fovea by its radial orientation of birefringent nerve fibers. The instrument used a four-quadrant photodetector and a normalized difference function to check for a best match between the detector quadrants and the arms of the bow-tie pattern of polarization states surrounding the fovea. This function had a maximum during central fixation but could not tell where the subject was looking relative to the center. We propose a linear transformation to obtain horizontal and vertical eye position coordinates from the four photodetector signals, followed by correction based on a priori calibration information. The method was verified on both a computer model and on human eyes. The major advantage of this new eye-tracking method is that it uses true information coming from the fovea, rather than reflections from other structures, to identify the direction of foveal gaze.

  13. Loiasis: African eye worm.

    PubMed

    Padgett, Jeannie J; Jacobsen, Kathryn H

    2008-10-01

    The filarial parasite Loa loa is transmitted by Chrysops fly bites. Loiasis is endemic in rainforest areas of West and Central Africa, and sporadic cases have also been diagnosed in travellers and migrants. Whilst many infected persons are asymptomatic, microfilariae may be detected in the blood or adult worms may be seen under the skin or the sclera of the eye. Mass treatment programmes for onchocerciasis have raised concern about the risk of severe adverse effects when ivermectin is distributed in areas co-endemic for onchocerciasis and loiasis.

  14. [Eye and lymph drainage].

    PubMed

    Grüntzig, J; Schicha, H; Huth, F

    1979-06-01

    Up to now lymphatics in the eye could not be pointed out. An ocular lymph drainage is denied. Földi succeeded in producing experimentally the syndrome of "lymphostatic encephalopathy and ophthalmopathy" by operative blockade of the cervical lymphatics in animals. In the first part of the present paper a historical view considering the subject "Eye and lymphatic system" is given. In the second part it is entered into the particulars of own experimental studies. As to our own investigations, rabbits have been injected 99mTc-sulfur-colloid, 99mTc-microcolloid, 99mTc-Albumin and 198Au-colloid into the retrobulbar space, anterior chamber, vitreous body and subconjuctival space of one eye. Measurements of the activity's distribution have been made in vivo with an Anger type camera (pho-Gamma-IV Hp, Searle Nuclear Chicago) and in vitro after section with a sodium iodine crystal well counter (Clinimat-200, Picker). In some animals the investigation has been combined with a bilateral dissection of the cervical lymph nodes. After injection in the retrobulbar space a significant concentration of the activity could be observed for the most part in the equilateral Lymphonodulus cervicalis profundus. By the cervical lymph blockade the removal of lymphoctopic substances from the retrobulbar space was largely inhibited. After injection in the anterior chamber a significant concentration could be observed for the most part in the equilateral Lymphonodulus cervicalis superficialis. After intravitreal injection a drainage to the bilateral deep cervical lymph nodes could be observed. After injection into the subconjunctival space a significant accumulation of activity could be registered in the equilateral Lymphonoduli mandibulares and cervicales superficiales. The data substantiate a segmental lymph drainage from the eye: vitreous body and retrobulbar space for the most part into the Lymphonoduli cervicales profundi, anterior chamber and subconjunctival space for the most part into

  15. Lens of Eye Dosimetry

    SciTech Connect

    Mallett, Michael Wesley

    2015-03-23

    An analysis of LANL occupational dose measurements was made with respect to lens of eye dose (LOE), in particular, for plutonium workers. Table 1 shows the reported LOE as a ratio of the “deep” (photon only) and “deep+neutron” dose for routine monitored workers at LANL for the past ten years. The data compares the mean and range of these values for plutonium workers* and non-routine plutonium workers. All doses were reported based on measurements with the LANL Model 8823 TLD.

  16. Influence of pitch tilts on the perception of gravity-referenced eye level in labyrinthine defective subjects.

    PubMed

    Bringoux, L; Mezey, L E; Faldon, M; Gresty, M A; Bronstein, A M

    2007-01-28

    We investigate the role of vestibular information in judging the gravity-referenced eye level (i.e., earth-referenced horizon or GREL) during sagittal body tilt whilst seated. Ten bilateral labyrinthine-defective subjects (LDS) and 10 age-matched controls set a luminous dot to their perception of GREL in darkness, with and without arm pointing. Although judgements were linearly influenced by the magnitude of whole-body tilt, results showed no significant difference between LDS and age-matched controls in the subjective GREL accuracy or in the intra-subject variability of judgement. However, LDS performance without arm pointing was related to the degree of vestibular compensation inferred from another postural study performed with the same patients. LDS did not utilize upper limb input during arm pointing movements as a source of graviceptive information to compensate for the vestibular loss. The data suggest that vestibular cues are not of prime importance in GREL estimates in static conditions. The absence of difference between controls and LDS GREL performance, and the correlation between the postural task and GREL accuracy, indicate that somatosensory input may convey as much graviceptive information required for GREL judgements as the vestibular system.

  17. On biometrics with eye movements.

    PubMed

    Zhang, Youming; Juhola, Martti

    2016-04-07

    Eye movements are a relatively novel data source for biometric identification. When video cameras applied to eye tracking become smaller and more efficient, this data source could offer interesting opportunities for the development of eye movement biometrics. In the present article, we study primarily biometric identification as seen as a classification task of multiple classes, and secondarily biometric verification considered as binary classification. Our research is based on the saccadic eye movement signal measurements from 109 young subjects. In order to test the data measured, we use a procedure of biometric identification according to the one-versus-one (subject) principle. In a development from our previous research, which also involved biometric verification based on saccadic eye movements, we now apply another eye movement tracker device with a higher sampling frequency of 250 Hz. The results obtained are good, with correct identification rates at 80-90% at their best.

  18. Eye tracking detects disconjugate eye movements associated with structural traumatic brain injury and concussion.

    PubMed

    Samadani, Uzma; Ritlop, Robert; Reyes, Marleen; Nehrbass, Elena; Li, Meng; Lamm, Elizabeth; Schneider, Julia; Shimunov, David; Sava, Maria; Kolecki, Radek; Burris, Paige; Altomare, Lindsey; Mehmood, Talha; Smith, Theodore; Huang, Jason H; McStay, Christopher; Todd, S Rob; Qian, Meng; Kondziolka, Douglas; Wall, Stephen; Huang, Paul

    2015-04-15

    Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 sec and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy noninjured control subjects and compared findings to 75 trauma subjects with either a positive head computed tomography (CT) scan (n=13), negative head CT (n=39), or nonhead injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure Sport Concussion Assessment Tool 3 (SCAT3) in trauma patients. Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to noninjured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain-injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion score. Abnormal eye-tracking metrics improved over time toward baseline in brain-injured subjects observed in follow-up. Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury.

  19. Eye Tracking Detects Disconjugate Eye Movements Associated with Structural Traumatic Brain Injury and Concussion

    PubMed Central

    Ritlop, Robert; Reyes, Marleen; Nehrbass, Elena; Li, Meng; Lamm, Elizabeth; Schneider, Julia; Shimunov, David; Sava, Maria; Kolecki, Radek; Burris, Paige; Altomare, Lindsey; Mehmood, Talha; Smith, Theodore; Huang, Jason H.; McStay, Christopher; Todd, S. Rob; Qian, Meng; Kondziolka, Douglas; Wall, Stephen; Huang, Paul

    2015-01-01

    Abstract Disconjugate eye movements have been associated with traumatic brain injury since ancient times. Ocular motility dysfunction may be present in up to 90% of patients with concussion or blast injury. We developed an algorithm for eye tracking in which the Cartesian coordinates of the right and left pupils are tracked over 200 sec and compared to each other as a subject watches a short film clip moving inside an aperture on a computer screen. We prospectively eye tracked 64 normal healthy noninjured control subjects and compared findings to 75 trauma subjects with either a positive head computed tomography (CT) scan (n=13), negative head CT (n=39), or nonhead injury (n=23) to determine whether eye tracking would reveal the disconjugate gaze associated with both structural brain injury and concussion. Tracking metrics were then correlated to the clinical concussion measure Sport Concussion Assessment Tool 3 (SCAT3) in trauma patients. Five out of five measures of horizontal disconjugacy were increased in positive and negative head CT patients relative to noninjured control subjects. Only one of five vertical disconjugacy measures was significantly increased in brain-injured patients relative to controls. Linear regression analysis of all 75 trauma patients demonstrated that three metrics for horizontal disconjugacy negatively correlated with SCAT3 symptom severity score and positively correlated with total Standardized Assessment of Concussion score. Abnormal eye-tracking metrics improved over time toward baseline in brain-injured subjects observed in follow-up. Eye tracking may help quantify the severity of ocular motility disruption associated with concussion and structural brain injury. PMID:25582436

  20. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a spring-loaded plexiglass 'flapper.' The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  1. Eye Surgery Light

    NASA Technical Reports Server (NTRS)

    1978-01-01

    During eye surgery, the surgeon uses an illuminating instrument called an opthalmoscope for close examination of the retina or the interior of the eye. Ordinarily, electric power for the head-mounted light is supplied through a cord from an overhead swivel arm or a floor pedestal. Within limits of cord length and swivel arm movement, the surgeon has considerable freedom of motion. But when more than one opthalmoscope is involved, tangling and interference of the power cords becomes a problem. St. Luke's Hospital, Cleveland, Ohio asked Lewis Research Center for assistance in finding a solution. Lewis responded with a battery-powered system that totally frees the surgeon of attached cords and swivels. Borrowing from space technology, Lewis used small, lightweight nickel-cadmium batteries that can deliver high intensity light for an hour and can be recharged overnight. The Opthalmoscope Powerpack consists of eight batteries in three containers affixed to a webbed belt, and a novel on-off switch equipped with a springloaded plexiglass "flapper." The belt pack is worn underneath the surgical gown and the flapper permits the doctor to activate the switch by elbow pressure. Lewis built five units and they have been in service at St. Luke's Hospital for a year. Used for routine examinations as well as for surgery, they have demonstrated excellent reliability.

  2. Aging and dry eye disease

    PubMed Central

    Ding, Juan; Sullivan, David A.

    2012-01-01

    Dry eye disease is a prevalent eye disorder that in particular affects the elderly population. One of the major causes of dry eye, meibomian gland dysfunction (MGD), shows increased prevalence with aging. MGD is caused by hyperkeratinization of the ductal epithelium of meibomian gland and reduced quantity and/or quality of meibum, the holocrine product that stabilizes and prevents the evaporation of the tear film. Of note, retinoids which are used in current anti-aging cosmetics may promote the development of MGD and dry eye disease. In this review, we will discuss the possible mechanisms of age-related MGD. PMID:22569356

  3. Developmental palaeobiology of trilobite eyes and its evolutionary significance

    NASA Astrophysics Data System (ADS)

    Thomas, A. T.

    2005-06-01

    Understanding of the calcified composite eyes of trilobites, the oldest preserved visual system, has advanced greatly in recent decades. Three types of trilobite eye occur, the more derived abathochroal and schizochroal types having evolved neotenically from holochroal eyes. Comparative morphology and phylogenetic considerations suggest that all three eye-types were underlain by common developmental systems. So far, understanding of these systems has been based entirely on morphological data from fossils, particularly the way the visual surface grew and the patterning of lens emplacement. Lenses characteristically form a hexagonal array comprising horizontal rows and, conspicuously in schizochroal eyes, dorso-ventral files. Because individual trilobites sometimes have eyes with different numbers of files, file number must reflect the operation of a developmental programme rather than being under immediate genetic control. An empirical developmental model has been devised to describe trilobite eye development, with separate rules dealing with the initiation of lens emplacement, growth and differentiation of the visual surface, and the termination of lens emplacement. Rarely, trilobites may have visual surfaces of normal size, but which lack lenses. This confirms that visual surface growth must have been regulated separately from lens emplacement, and is a feature that cannot be accounted for by the existing developmental model. Such a developmental separation is one of a number of similarities shared with Drosophila, the modern arthropod in which eye development is best understood. Many aspects of eye development are conserved in the Euarthropoda, and in bilaterian metazoans in general. A revised model for trilobite eye development is proposed using extant phylogenetic bracketing, interpreting morphological data from the fossils in the context of the hierarchy of developmental controls now becoming known from living animals. This new model suggests that overall eye

  4. Normal facial age and gender perception in developmental prosopagnosia.

    PubMed

    Chatterjee, Garga; Nakayama, Ken

    2012-01-01

    Developmental prosopagnosia is characterized by a severe deficit in face-identity recognition. Most developmental prosopagnosics do not report deficits of facial age or gender perception. We developed tasks for evaluating facial age and gender processing and used them in the largest group of developmental prosopagnosics (N = 18) tested on facial age and gender perception. Care was taken to ensure that the tests were sufficiently sensitive to subtle deficits and required holistic processing as assessed by strong inversion effects in control subjects. Despite severe facial identity deficits, developmental prosopagnosics largely performed these discriminations comparably to controls. The common descriptor "faceblind" implied by the term prosopagnosia is inaccurate as certain kinds of nonidentity facial information, which we call physiognomic features, are processed well by both prosopagnosics and age-matched controls alike. Normal facial age and gender perception in developmental prosopagnosics is consistent with parallel processing models in the cognitive architecture of face processing.

  5. Protect Their Eyes: An Eye Safety Guide for the Classroom.

    ERIC Educational Resources Information Center

    Ohio Society to Prevent Blindness, Columbus.

    This guide provides information on eye safety and aids educators, administrators, and supervisors in the development and implementation of eye safety programs. The American National Standards Institute (AMSI) requirements for both street and safety glasses; essential eyewear for safety in hazardous areas; the National Society to Prevent…

  6. Evaluation of Dry Eye and Meibomian Gland Dysfunction in Teenagers with Myopia through Noninvasive Keratograph

    PubMed Central

    Wang, Xiu; Lu, Xiaoxiao; Yang, Jun; Wei, Ruihua; Yang, Liyuan; Zhao, Shaozhen; Wang, Xilian

    2016-01-01

    Purpose. This study aims to evaluate dry eye and ocular surface conditions of myopic teenagers by using questionnaire and clinical examinations. Methods. A total of 496 eyes from 248 myopic teenagers (7–18 years old) were studied. We administered Ocular Surface Disease Index (OSDI) questionnaire, slit-lamp examination, and Keratograph 5M. The patients were divided into 2 groups based on OSDI dry eye standard, and their ocular surfaces and meibomian gland conditions were evaluated. Results. The tear meniscus heights of the dry eye and normal groups were in normal range. Corneal fluorescein scores were significantly higher whereas noninvasive break-up time was dramatically shorter in the dry eye group than in the normal group. All three meibomian gland dysfunction parameters (i.e., meibomian gland orifice scores, meibomian gland secretion scores, and meibomian gland dropout scores) of the dry eye group were significantly higher than those of the normal group (P < 0.0001). Conclusions. The prevalence of dry eye in myopic teenagers is 18.95%. Meibomian gland dysfunction plays an important role in dry eye in myopic teenagers. The Keratograph 5M appears to provide an effective noninvasive method for assessing ocular surface situation of myopic teenagers. PMID:26881059

  7. The Relationship of Saccadic Eye Movements to Reading Disabilities. Final Report.

    ERIC Educational Resources Information Center

    Ross, Alan O.

    Saccadic (small, rapid, and apparently involuntary) eye movements of 14 children (7- to 12-years-old) with reading difficulties and of 14 normal readers were compared before and after the problem readers underwent a 7-month individual tutoring program. At pretesting the problem readers showed a rate of eye movements that was markedly lower than…

  8. The Role of Face Familiarity in Eye Tracking of Faces by Individuals with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Sterling, Lindsey; Dawson, Geraldine; Webb, Sara; Murias, Michael; Munson, Jeffrey; Panagiotides, Heracles; Aylward, Elizabeth

    2008-01-01

    It has been shown that individuals with autism spectrum disorders (ASD) demonstrate normal activation in the fusiform gyrus when viewing familiar, but not unfamiliar faces. The current study utilized eye tracking to investigate patterns of attention underlying familiar versus unfamiliar face processing in ASD. Eye movements of 18 typically…

  9. [Ocular surface investigations in dry eye].

    PubMed

    Labbé, A; Brignole-Baudouin, F; Baudouin, C

    2007-01-01

    Dry eye is a complex clinicopathological entity involving tear film, lacrimal glands, eyelids, and a wide spectrum of ocular surface cells, including epithelial, inflammatory, immune, and goblet cells. From the tightly regulated lacrimal film functions and structure, a large variety of investigations have been developed, including tear meniscus measurements, fluorophotometry, meibometry, interference pattern analysis, evaporation rate, tear osmolarity, and thermography. Dry eye conditions also interfere with the ocular surface, causing corneal irregularities that may be explored using the techniques of videokeratography and in vivo confocal microscopy, or optical impairment, as confirmed by aberrometry. At the level of ocular surface cells, impression cytology remains a standard for assessing cell alterations. It has greatly benefited from new confocal microscopy, molecular biology, and flow cytometry techniques. Biological assessment of tear proteins or other mediators is also useful. Major limits should be acknowledged, however, such as technical issues in tear film collection, especially in dry eyes, and the lack of standardization of most measurements. Tear osmolarity, electrophoresis, and dosage of normal tear proteins, such as lysozyme or lactoferrin, remain the most useful tests. Finally, some extraocular explorations such as accessory gland biopsy or serum antinuclear antibody dosage may be useful for assessing the diagnosis of Sjögren's syndrome.

  10. Wavefront Derived Refraction and Full Eye Biometry in Pseudophakic Eyes

    PubMed Central

    Mao, Xinjie; Banta, James T.; Ke, Bilian; Jiang, Hong; He, Jichang; Liu, Che; Wang, Jianhua

    2016-01-01

    Purpose To assess wavefront derived refraction and full eye biometry including ciliary muscle dimension and full eye axial geometry in pseudophakic eyes using spectral domain OCT equipped with a Shack-Hartmann wavefront sensor. Methods Twenty-eight adult subjects (32 pseudophakic eyes) having recently undergone cataract surgery were enrolled in this study. A custom system combining two optical coherence tomography systems with a Shack-Hartmann wavefront sensor was constructed to image and monitor changes in whole eye biometry, the ciliary muscle and ocular aberration in the pseudophakic eye. A Badal optical channel and a visual target aligning with the wavefront sensor were incorporated into the system for measuring the wavefront-derived refraction. The imaging acquisition was performed twice. The coefficients of repeatability (CoR) and intraclass correlation coefficient (ICC) were calculated. Results Images were acquired and processed successfully in all patients. No significant difference was detected between repeated measurements of ciliary muscle dimension, full-eye biometry or defocus aberration. The CoR of full-eye biometry ranged from 0.36% to 3.04% and the ICC ranged from 0.981 to 0.999. The CoR for ciliary muscle dimensions ranged from 12.2% to 41.6% and the ICC ranged from 0.767 to 0.919. The defocus aberrations of the two measurements were 0.443 ± 0.534 D and 0.447 ± 0.586 D and the ICC was 0.951. Conclusions The combined system is capable of measuring full eye biometry and refraction with good repeatability. The system is suitable for future investigation of pseudoaccommodation in the pseudophakic eye. PMID:27010674

  11. Formation of the hurricane eye

    NASA Astrophysics Data System (ADS)

    Vigh, Jonathan L.

    This dissertation consists of three distinct studies which investigate aspects of eye formation. The first study reviews eye phenomenon in a variety of vortices ranging from simple vortices to the menagerie of geophysical vortices, emphasizing similarities and differences to the eyes formed in hurricanes. The hurricane eye is found to be a paradoxical structure imposed by conservation of angular momentum and the boundaries of the vortex. A comprehensive definition for hurricane eye formation is proposed and various eye formation mechanisms are summarized. The next study presents a simple theoretical argument to isolate the conditions under which a tropical cyclone can rapidly develop a warm-core thermal structure and subsequently approach a steady state. The theoretical argument is based on the balanced vortex model and, in particular, on the associated transverse circulation equation and the geopotential tendency equation. The transverse circulation and the temperature tendency in a tropical vortex depend not only on the diabatic forcing, but also on the spatial distributions of the static stability, the baroclinity, and the inertial stability. The vortex response to diabatic heating depends critically on whether the heating occurs in the low inertial stability region outside the radius of maximum wind or in the high inertial stability region inside the radius of maximum wind. This result suggests that rapid intensification is favored for storms which have at least some of the eyewall convection inside the radius of maximum wind. The development of an eye partially removes diabatic heating from the high inertial stability region of the storm center, yet rapid intensification may continue if the eyewall heating continues to become more efficient. As the warm core matures and static stability increases over the inner core, conditions there become less favorable for deep upright convection and the storm tends to approach a steady state. The final study characterizes

  12. Choosing Wisely When It Comes to Eye Care: Antibiotics for Pink Eye

    MedlinePlus

    ... Eye Health A-Z Symptoms Glasses & Contacts Tips & Prevention News Ask an ... healthy lifestyle choices can help you protect your vision by reducing your risk for eye diseases , eye infections and eye injuries . Partnering with your ...

  13. Eyes of Ganges

    NASA Technical Reports Server (NTRS)

    2005-01-01

    21 December 2005 This Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows eroded, light-toned layered rock outcrops on the side of a large mound in Ganges Chasma, part of the vast Valles Marineris trough system. Perhaps a testament to the inherent human (and primate) ability to pick out faces where partially hidden from view (even when a face is not really there) -- near the top of this picture are two features, each a product of erosion, resembling a pair of human eyes. This picture was acquired in late November 2005.

    Location near: 7.1oS, 49.4oW Image width: width: 0.55 km (0.3 mi) Illumination from: left/lower left Season: Southern Summer

  14. [Diabetic eye disease].

    PubMed

    Henriques, José; Vaz-Pereira, Sara; Nascimento, João; Rosa, Paulo Caldeira

    2015-01-01

    Diabetes mellitus is a chronic metabolic disease characterized by sustained hyperglycemia leading to macro and microvascular complications. The eye is one of the main organs affected by this disease, being diabetic retinopathy the most well-known microvascular complication and the leading cause of blindness in the working age population. However, diabetic ocular disease is not only characterized by diabetic retinopathy. Other important ocular manifestations of diabetes mellitus include cataract, glaucoma, ischemic optic neuropathy, cranial nerve palsies and recurrent corneal erosion syndrome. Here, we emphasize diabetic retinopathy as the most important and characteristic complication of diabetes mellitus, but also review less well-known complications with the aim to alert and sensitize non-ophthalmologist clinicians that treat diabetic individuals, in order to promote an early diagnosis and treatment of the sight-threatening complications of diabetes.

  15. Pregnancy and the Eye

    PubMed Central

    Yenerel, Nursal Melda; Küçümen, Raciha Beril

    2015-01-01

    Pregnancy causes significant changes in all systems of the body. Although most of them are physiological, they may also lead to pathological consequences. The resulting pathological changes may occur for the first time or existing diseases affected by pregnancy can become more serious or change course. Diseases specific only to pregnancy may arise. Like all systems of the body, the visual system is also affected by pregnancy, developing a wide range of physiological and pathological changes. Knowing the ocular physiological changes and diagnosing eye diseases that may develop during pregnancy, and preventing and treating these diseases is crucial to ensure the baby’s healthy development. Therefore, we have reviewed the conditions that an ophthalmologist should recognize, follow-up, and pay attention to during treatment and summarized them under the topic “pregnancy and the eye”. PMID:27800235

  16. The Colossal Cosmic Eye

    NASA Astrophysics Data System (ADS)

    2005-09-01

    Eighty-five million years ago on small planet Earth, dinosaurs ruled, ignorant of their soon-to-come demise in the great Jurassic extinction, while mammals were still small and shy creatures. The southern Andes of Bolivia, Chile, and Argentina were not yet formed and South America was still an island continent. Eighty-five million years ago, our Sun and its solar system was 60,000 light years away from where it now stands [1]. Eighty-five million years ago, in another corner of the Universe, light left the beautiful spiral galaxy NGC 1350, for a journey across the universe. Part of this light was recorded at the beginning of the year 2000 AD by ESO's Very Large Telescope, located on the 2,600m high Cerro Paranal in the Chilean Andes on planet Earth. Astronomers classify NGC 1350 as an Sa(r) type galaxy, meaning it is a spiral with large central regions. In fact, NGC 1350 lies at the border between the broken-ring spiral type and a grand design spiral with two major outer arms. It is about 130,000 light-years across and, hence, is slightly larger than our Milky Way. The rather faint and graceful outer arms originate at the inner main ring and can be traced for almost half a circle when they each meet the opposite arm, giving the impression of completing a second outer ring, the "eye". The arms are given a blue tint as a result of the presence of very young and massive stars. The amount of dust, seen as small fragmented dust spirals in the central part of the galaxy and producing a fine tapestry that bear resemblance with blood vessels in the eye, is also a signature of the formation of stars.

  17. Miniature curved artificial compound eyes

    PubMed Central

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L’Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A.; Franceschini, Nicolas

    2013-01-01

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories. PMID:23690574

  18. Eye trauma in the workplace

    SciTech Connect

    Boyd-Monk, H.

    1990-10-01

    A baseline visual acuity should be on record for medical and legal purposes. Identifying an eye injury and referring the person for appropriate treatment can save vision. Immediate eye irrigation in the case of chemical burns can substantially decrease the possibility of permanent vision damage.

  19. Photographic Screening for Eye Defects

    NASA Technical Reports Server (NTRS)

    Richardson, J.

    1985-01-01

    Images of retinas examined for characteristic patterns. Color photographs of retinas taken. Proper alinement of eye obtained by asking subject to gaze at light-emitting diode. "Red-eye" patterns in resulting color photographs examined by trained observers for signs of ocular defects. System used to check power of contact lenses and eyeglasses by taking photographs with these items in place.

  20. Dry eye disease after LASIK

    PubMed Central

    Ţuru, L; Alexandrescu, C; Stana, D; Tudosescu, R

    2012-01-01

    LASIK is a surgical tehnique for the correction of refractive errors (myopia, hyperopia, astygmatism). It results in a reshape of the cornea with ocular surface and especially tear film disease. It is a cause for a iatrogenic dry eye syndrome. Neurogenic and inflamatory theory explain this disease. The main therapy of dry eye is the replacement with artificial tears. PMID:22574092

  1. Miniature curved artificial compound eyes.

    PubMed

    Floreano, Dario; Pericet-Camara, Ramon; Viollet, Stéphane; Ruffier, Franck; Brückner, Andreas; Leitel, Robert; Buss, Wolfgang; Menouni, Mohsine; Expert, Fabien; Juston, Raphaël; Dobrzynski, Michal Karol; L'Eplattenier, Geraud; Recktenwald, Fabian; Mallot, Hanspeter A; Franceschini, Nicolas

    2013-06-04

    In most animal species, vision is mediated by compound eyes, which offer lower resolution than vertebrate single-lens eyes, but significantly larger fields of view with negligible distortion and spherical aberration, as well as high temporal resolution in a tiny package. Compound eyes are ideally suited for fast panoramic motion perception. Engineering a miniature artificial compound eye is challenging because it requires accurate alignment of photoreceptive and optical components on a curved surface. Here, we describe a unique design method for biomimetic compound eyes featuring a panoramic, undistorted field of view in a very thin package. The design consists of three planar layers of separately produced arrays, namely, a microlens array, a neuromorphic photodetector array, and a flexible printed circuit board that are stacked, cut, and curved to produce a mechanically flexible imager. Following this method, we have prototyped and characterized an artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. The prototyped artificial compound eye possesses several characteristics similar to the eye of the fruit fly Drosophila and other arthropod species. This design method opens up additional vistas for a broad range of applications in which wide field motion detection is at a premium, such as collision-free navigation of terrestrial and aerospace vehicles, and for the experimental testing of insect vision theories.

  2. Occupational eye injuries in Finland.

    PubMed

    Saari, K M; Parvi, V

    1984-01-01

    In Finland 11.9% of all industrial accidents in 1973 were eye injuries including superficial eye injuries (79.2%), ultraviolet burns of the cornea (3.9%), eye burns (3.6%), blunt ocular trauma (2,5%), wounds (2.4%), and post-traumatic infections (5.8%). Eye injuries constituted 34.3% of all industrial accidents which needed only ambulatory treatment and 17.5% of all industrial accidents causing an absence for 1-2 days. In 1981 2.1% of all compensated industrial accidents (incapacity for work 3 days or more) were eye injuries. Most compensated eye injuries occurred in manufacturing and in construction work (80.4%) and 8.5% occurred in agriculture. The annual incidence rates of compensated accidents to the eyes (accidents X 1 000/number of employees) were highest in several branches of metal industry (4.96-6.88), excavating and foundation work (6.88), and in logging (5.64). Compensated eye injuries were caused by machines (32.8%), hand tools (25.6%), other equipment and constructions (4.8%), work environment (23.6%), chemical substances (10.8%), and other accidents (2.3%).

  3. Numerical abilities of school-age children with Developmental Coordination Disorder (DCD): A behavioral and eye-tracking study.

    PubMed

    Gomez, Alice; Piazza, Manuela; Jobert, Antoinette; Dehaene-Lambertz, Ghislaine; Huron, Caroline

    2016-08-31

    Developmental Coordination Disorder (DCD) is a disorder of motor coordination which interferes with academic achievement. Difficulties in mathematics have been reported. Performance in the number line task is very sensitive to atypical development of numerical cognition. We used a position-to-number task in which twenty 7-to-10years old children with DCD and 20 age-matched typically developing (TD) children had to estimate the number that corresponded to a hatch mark placed on a 0-100 number line. Eye movements were recorded. Children with DCD were less accurate and slower to respond than their peers. However, they were able to map numbers onto space linearly and used anchoring strategies as control. We suggest that the shift to a linear trend reflects the ability of DCD children to use efficient strategies to solve the task despite a possibly more imprecise underlying numerical acuity.

  4. [Eye involvement of borrelia aetiology].

    PubMed

    Krbková, Lenka; Vodicková, Kristýna; Pellarová, Hana; Bednárová, Jana; Cápová, Iva

    2007-06-01

    We present a case of eye involvement -- intermediate uveitis -- during tick-borne borreliosis in a 10-year-old boy. Ophthalmologic examination revealed impaired vision, apparent thick floating whitish opacity in the vitreous humour of the left eye and fine fibres in the vitreous humour of the right eye. Sonographic examination confirmed hyperechogenic opacity in the vitreous humour. An autoimmune process was suspected but not confirmed. Serological examination showed IgG antibodies against three pathogenic borreliae and borderline values of IgM antibodies against Borrelia garinii were found by immunoblot. The boy was treated with intravenous ceftriaxone for 21 days. The subsequent sonographic examination showed only minute sporadic echogenicity. Biomicroscopically, only residual opacity in the vitreous humour was found. Isolated eye involvement of borrelia aetiology is rare. The discussion provides a review of similar cases of uveitis including diagnosis of the eye form as published in literature.

  5. I Can Read It in Your Eyes: What Eye Movements Tell Us about Visuo-Attentional Processes in Developmental Dyslexia

    ERIC Educational Resources Information Center

    Bellocchi, Stephanie; Muneaux, Mathilde; Bastien-Toniazzo, Mireille; Ducrot, Stephanie

    2013-01-01

    Most studies today agree about the link between visual-attention and oculomotor control during reading: attention seems to affect saccadic programming, that is, the position where the eyes land in a word. Moreover, recent studies show that visuo-attentional processes are strictly linked to normal and impaired reading. In particular, a large body…

  6. Evaluation of different projectiles in matched experimental eye impact simulations.

    PubMed

    Weaver, Ashley A; Kennedy, Eric A; Duma, Stefan M; Stitzel, Joel D

    2011-03-01

    Eye trauma results in 30,000 cases of blindness each year in the United States and is the second leading cause of monocular visual impairment. Eye injury is caused by a wide variety of projectile impacts and loading scenarios with common sources of trauma being motor vehicle crashes, military operations, and sporting impacts. For the current study, 79 experimental eye impact tests in literature were computationally modeled to analyze global and localized responses of the eye to a variety of blunt projectile impacts. Simulations were run with eight different projectiles (airsoft pellets, baseball, air gun pellets commonly known as BBs, blunt impactor, paintball, aluminum, foam, and plastic rods) to characterize effects of the projectile size, mass, geometry, material properties, and velocity on eye response. This study presents a matched comparison of experimental test results and computational model outputs including stress, energy, and pressure used to evaluate risk of eye injury. In general, the computational results agreed with the experimental results. A receiver operating characteristic curve analysis was used to establish the stress and pressure thresholds that best discriminated for globe rupture in the matched experimental tests. Globe rupture is predicted by the computational simulations when the corneoscleral stress exceeds 17.21 MPa or the vitreous pressure exceeds 1.01 MPa. Peak stresses were located at the apex of the cornea, the limbus, or the equator depending on the type of projectile impacting the eye. A multivariate correlation analysis revealed that area-normalized kinetic energy was the best single predictor of peak stress and pressure. Additional incorporation of a relative size parameter that relates the projectile area to the area of the eye reduced stress response variability and may be of importance in eye injury prediction. The modeling efforts shed light on the injury response of the eye when subjected to a variety of blunt projectile

  7. Salivation induced better lacrimal gland function in dry eyes.

    PubMed

    Pramanik, T; Ghising, R

    2009-12-01

    The dry eye syndrome is a common eye symptom causing blurry vision. To meet the demand of the modem world students and professionals are compelled to expose themselves to the computer screen for long stretch of time, which is one of the causes of dry eye. It is not always feasible to instil eyes with artificial tears time to time to protect them from dryness. Rather to adopt any simple physiological process associated with optimum lacrimation is a better option to keep eyes moist during computer works. Volunteers (n = 22) having mild dry eyes participated in this study. Tear production was assessed by Schirmer test by keeping Schirmer strip on ocular surface for 5 minutes and recording the length of the moistened area. Then the subject was allowed to keep a piece of lopsy candy (a sour fruit pulp mixed with sugar that is sweet and sour in taste) in mouth for 5 minutes that caused salivation. During salivation, again tear production was assessed. [It was standardized in such a way that, the length of the moistened strip will be 25 - 30 mm for normal eyes, 15 - 10 mm for dry eye, 06 - 10 mm for mild dry eye, 02 - 05 mm for moderate dryness and 00 - 01 mm for severe dry eye.] Tear production was found to be increased significantly (supported by increased length of moistened area of Schirmer strip) during salivation especially in dry eye in all volunteers. The lacrimal gland is the major contributor to the aqueous layer of the tear film which consists of water, electrolytes and proteins; secretion of which are under tight neural control. Anticholinergic agents play an important role in ocular dryness because of hypo-secretion. The sensory root of facial nucleus contains efferent preganglionic parasympathetic fibers for submandibular and sublingual salivary gland and lacrimal gland. The sensory root conveys gustatory fibers from the presulcul area (anterior two-third) of the tongue via the chorda tympani and via the palatine and greater petrosal nerve, taste fibers from

  8. Registering eye movements during reading in Alzheimer's disease: difficulties in predicting upcoming words.

    PubMed

    Fernández, Gerardo; Laubrock, Jochen; Mandolesi, Pablo; Colombo, Oscar; Agamennoni, Osvaldo

    2014-01-01

    Reading requires the fine integration of attention, ocular movements, word identification, and language comprehension, among other cognitive parameters. Several of the associated cognitive processes such as working memory and semantic memory are known to be impaired by Alzheimer's disease (AD). This study analyzes eye movement behavior of 18 patients with probable AD and 40 age-matched controls during Spanish sentence reading. Controls focused mainly on word properties and considered syntactic and semantic structures. At the same time, controls' knowledge and prediction about sentence meaning and grammatical structure are quite evident when we consider some aspects of visual exploration, such as word skipping, and forward saccades. By contrast, in the AD group, the predictability effect of the upcoming word was absent, visual exploration was less focused, fixations were much longer, and outgoing saccade amplitudes were smaller than those in controls. The altered visual exploration and the absence of a contextual predictability effect might be related to impairments in working memory and long-term memory retrieval functions. These eye movement measures demonstrate considerable sensitivity with respect to evaluating cognitive processes in Alzheimer's disease. They could provide a user-friendly marker of early disease symptoms and of its posterior progression.

  9. The Effect of Residual Acoustic Hearing and Adaptation to Uncertainty on Speech Perception in Cochlear Implant Users: Evidence from Eye-Tracking

    PubMed Central

    McMurray, Bob; Farris-Trimble, Ashley; Seedorff, Michael; Rigler, Hannah

    2015-01-01

    Objectives While outcomes with cochlear implants (CIs) are generally good, performance can be fragile. The authors examined two factors that are crucial for good CI performance. First, while there is a clear benefit for adding residual acoustic hearing to CI stimulation (typically in low frequencies), it is unclear whether this contributes directly to phonetic categorization. Thus, the authors examined perception of voicing (which uses low-frequency acoustic cues) and fricative place of articulation (s/ʃ, which does not) in CI users with and without residual acoustic hearing. Second, in speech categorization experiments, CI users typically show shallower identification functions. These are typically interpreted as deriving from noisy encoding of the signal. However, psycholinguistic work suggests shallow slopes may also be a useful way to adapt to uncertainty. The authors thus employed an eye-tracking paradigm to examine this in CI users. Design Participants were 30 CI users (with a variety of configurations) and 22 age-matched normal hearing (NH) controls. Participants heard tokens from six b/p and six s/ʃ continua (eight steps) spanning real words (e.g., beach/peach, sip/ship). Participants selected the picture corresponding to the word they heard from a screen containing four items (a b-, p-, s- and ʃ-initial item). Eye movements to each object were monitored as a measure of how strongly they were considering each interpretation in the moments leading up to their final percept. Results Mouse-click results (analogous to phoneme identification) for voicing showed a shallower slope for CI users than NH listeners, but no differences between CI users with and without residual acoustic hearing. For fricatives, CI users also showed a shallower slope, but unexpectedly, acoustic + electric listeners showed an even shallower slope. Eye movements showed a gradient response to fine-grained acoustic differences for all listeners. Even considering only trials in which a

  10. Objective evaluation of the visual acuity in human eyes

    NASA Astrophysics Data System (ADS)

    Rosales, M. A.; López-Olazagasti, E.; Ramírez-Zavaleta, G.; Varillas, G.; Tepichín, E.

    2009-08-01

    Traditionally, the quality of the human vision is evaluated by a subjective test in which the examiner asks the patient to read a series of characters of different sizes, located at a certain distance of the patient. Typically, we need to ensure a subtended angle of vision of 5 minutes, which implies an object of 8.8 mm high located at 6 meters (normal or 20/20 visual acuity). These characters constitute what is known as the Snellen chart, universally used to evaluate the spatial resolution of the human eyes. The mentioned process of identification of characters is carried out by means of the eye - brain system, giving an evaluation of the subjective visual performance. In this work we consider the eye as an isolated image-forming system, and show that it is possible to isolate the function of the eye from that of the brain in this process. By knowing the impulse response of the eye´s system we can obtain, in advance, the image of the Snellen chart simultaneously. From this information, we obtain the objective performance of the eye as the optical system under test. This type of results might help to detect anomalous situations of the human vision, like the so called "cerebral myopia".

  11. Binocular eye tracking with the Tracking Scanning Laser Ophthalmoscope.

    PubMed

    Stevenson, S B; Sheehy, C K; Roorda, A

    2016-01-01

    The development of high magnification retinal imaging has brought with it the ability to track eye motion with a precision of less than an arc minute. Previously these systems have provided only monocular records. Here we describe a modification to the Tracking Scanning Laser Ophthalmoscope (Sheehy et al., 2012) that splits the optical path in a way that slows the left and right retinas to be scanned almost simultaneously by a single system. A mirror placed at a retinal conjugate point redirects half of each horizontal scan line to the fellow eye. The collected video is a split image with left and right retinas appearing side by side in each frame. Analysis of the retinal motion in the recorded video provides an eye movement trace with very high temporal and spatial resolution. Results are presented from scans of subjects with normal ocular motility that fixated steadily on a green laser dot. The retinas were scanned at 4° eccentricity with a 2° square field. Eye position was extracted offline from recorded videos with an FFT based image analysis program written in Matlab. The noise level of the tracking was estimated to range from 0.25 to 0.5arcmin SD for three subjects. In the binocular recordings, the left eye/right eye difference was 1-2arcmin SD for vertical motion and 10-15arcmin SD for horizontal motion, in agreement with published values from other tracking techniques.

  12. Dry Eyes and Glaucoma: Double Trouble

    MedlinePlus

    ... News About Us Donate In This Section Dry Eyes and Glaucoma: Double Trouble email Send this article ... disease bothers the patient more. What Causes Dry Eye Syndrome? Dry eye can be caused by many ...

  13. What Happens After Treatment for Eye Cancer?

    MedlinePlus

    ... Cancer After Treatment What Happens After Treatment for Eye Cancer? For many people with eye cancer, treatment ... manage them. Follow-up after treatment of uveal (eye) melanoma Your doctor will most likely want to ...

  14. [Eye connective tissues: cornea and vitreous body].

    PubMed

    Labat-Robert, Jacqueline; Pouliquen, Yves; Robert, Ladislas

    2012-01-01

    The authors, ophtalmologist (Y.P.) and basic scientists (J.L.-R and L.R.), collaborated on eye-research since 1962 on normal and pathological aspects of eye tissues, considered as specialized forms of connective tissues, and on specific aspects of the physiology and pathology of the eye. This date coincides with the foundation of the French Society of Connective Tissues, which celebrates the 50th anniversary of its creation. We shall present here some of our work on the ontogenetic and phylogenetic aspects of the cornea, on its structure, function and regulation in normal and pathological states, taken from a large number of publications of our laboratories. Our work on cornea started with the study of the morphogenesis of its lamellar structure, made of collagen fibers and proteoglycans. This led us to the isolation and characterization of structural (or matrix) glycoproteins, a new class of matrix components, present also in all other connective tissues, and to the study of their biosynthesis by keratocytes. Corneal wounds and regeneration were also studied, as well as some corneal pathologies such as keratoconus. The confrontation of quantitative morphological methods with biochemical procedures were to yield important results on the mechanisms of the maintenance of corneal structure and function. Another series of studies concerned the vitreous where we detected, besides previously characterized components, such as hyaluronan and collagens, fibronectin which plays an important role in the adhesion of hyaluronan to the collagen network. Its age-dependent modifications were also studied, with a special focus on the role of reactive oxygen species (ROS)-mediated degradation of hyaluronan, especially important for the aging of the vitreous.

  15. Eye damage control by reduced blue illumination.

    PubMed

    Ueda, Toshihiko; Nakanishi-Ueda, Takako; Yasuhara, Hajime; Koide, Ryohei; Dawson, William W

    2009-12-01

    The aim of this study was to demonstrate that a blue light and ultraviolet cut-off filter (blue filter) could reduce short-wavelength retina/RPE damage threshold by a continuous spectrum source. Sixteen normal eyes of two rhesus monkeys and six cynomolgus monkeys were subjected to macular irradiation of 20, 24, 27.4, 30, 35, 45, 50 and 60 J/cm(2) energy densities. The values of energy density were measured before the blue filter. Lesions were measured before and at 2 and 30 days after irradiation of a 2.8 mm diameter region within the macular arcade. Measures were fundoscopy, fluorescein angiography and long wavelength scanning by the Heidelberg Retinal Tomograph (HRT) unit. The lesions, which were produced, were scored and compared to irradiant energy density of the blue LED (NSPB500S, Nichia, Tokushima, Japan). The exposure at the 20 J/cm(2) produced no detectable result at 2 or 30 days. Exposure at 35 J/cm(2) showed definite lesion production without blue filter. With the filter added there was one indication of minor change. At 60 J/cm(2) there was extensive heavy, enduring damage without the filter and with the filter damage was present but was significantly attenuated. These results strongly support the conclusion that the blue filter attenuation reduces the frequency of damage by exposure. This experimental system is a useful model for normal human eye aging and continuous spectrum environment irradiance.

  16. A cyclopean neural mechanism compensating for optical differences between the eyes.

    PubMed

    Radhakrishnan, Aiswaryah; Dorronsoro, Carlos; Sawides, Lucie; Webster, Michael A; Marcos, Susana

    2015-03-02

    The two eyes of an individual routinely differ in their optical and neural properties, yet percepts through either eye remain more similar than predicted by these differences. Little is known as to how the brain resolves this conflicting information. Differences in visual inputs from the two eyes have been studied extensively in the context of binocular vision and rivalry [1], but it remains unknown how the visual system calibrates and corrects for normal variability in image quality between the eyes, and whether this correction is applied to each eye separately or after their signals have converged. To test this, we used adaptive optics to control and manipulate the blur projected on each retina, and then compared judgments of image focus through either eye and how these judgments were biased by adapting to different levels of blur. Despite significant interocular differences in the magnitude of optical blur, the blur level that appeared best focused was the same through both eyes, and corresponded to the ocular blur of the less aberrated eye. Moreover, for both eyes, blur aftereffects depended on whether the adapting blur was stronger or weaker than the native blur of the better eye, with no aftereffect when the blur equaled the aberrations of the better eye. Our results indicate that the neural calibration for the perception of image focus reflects a single 'cyclopean' site that is set monocularly by the eye with better optical quality. Consequently, what people regard as 'best-focused' matches the blur encountered through the eye with better optics, even when judging the world through the eye with poorer optics.

  17. Visual-field function in pseudophakia.

    PubMed

    Klewin, K M; Radius, R L; Schultz, R O

    1988-08-01

    An automated perimeter (Octopus 2000) was used to examine visual-field function in 52 pseudophakic eyes. Threshold sensitivity was reduced throughout the visual field by from 0.4 to 20.0 decibels from that of threshold sensitivity in age-matched normal eyes. This reduction was comparable to that seen in contact-lens-corrected aphakic eyes.

  18. A new experimental device to evaluate eye ulcers using a multispectral electrical impedance technique

    NASA Astrophysics Data System (ADS)

    Bellotti, Mariela I.; Bast, Walter; Berra, Alejandro; Bonetto, Fabián J.

    2011-07-01

    We present a novel experimental technique to determine eye ulcers in animals using a spectral electrical impedance technique. We expect that this technique will be useful in dry eye syndrome. We used a sensor that is basically a platinum (Pt) microelectrode electrically insulated by glass from a cylindrical stainless steel counter-electrode. This sensor was applied to the naked eye of New Zealand rabbits (2.0-3.5 kg in weight). Whereas half of the eyes were normal (control), we applied to the remainder a few drops of 20% (v/v) alcohol to produce an ulcer in the eye. Using a multispectral electrical impedance system we measured ulcerated and control eyes and observed significant difference between normal and pathological samples. We also investigated the effects of different applied pressures and natural degradation of initially normal eyes as a function of time. We believe that this technique could be sufficiently sensitive and repetitive to help diagnose ocular surface diseases such as dry eye syndrome.

  19. Eye movements during visual search in patients with glaucoma

    PubMed Central

    2012-01-01

    Background Glaucoma has been shown to lead to disability in many daily tasks including visual search. This study aims to determine whether the saccadic eye movements of people with glaucoma differ from those of people with normal vision, and to investigate the association between eye movements and impaired visual search. Methods Forty patients (mean age: 67 [SD: 9] years) with a range of glaucomatous visual field (VF) defects in both eyes (mean best eye mean deviation [MD]: –5.9 (SD: 5.4) dB) and 40 age-related people with normal vision (mean age: 66 [SD: 10] years) were timed as they searched for a series of target objects in computer displayed photographs of real world scenes. Eye movements were simultaneously recorded using an eye tracker. Average number of saccades per second, average saccade amplitude and average search duration across trials were recorded. These response variables were compared with measurements of VF and contrast sensitivity. Results The average rate of saccades made by the patient group was significantly smaller than the number made by controls during the visual search task (P = 0.02; mean reduction of 5.6% (95% CI: 0.1 to 10.4%). There was no difference in average saccade amplitude between the patients and the controls (P = 0.09). Average number of saccades was weakly correlated with aspects of visual function, with patients with worse contrast sensitivity (PR logCS; Spearman’s rho: 0.42; P = 0.006) and more severe VF defects (best eye MD; Spearman’s rho: 0.34; P = 0.037) tending to make less eye movements during the task. Average detection time in the search task was associated with the average rate of saccades in the patient group (Spearman’s rho = −0.65; P < 0.001) but this was not apparent in the controls. Conclusions The average rate of saccades made during visual search by this group of patients was fewer than those made by people with normal vision of a similar average age. There was wide

  20. Superglue injuries of the eye

    PubMed Central

    Reddy, Sagili Chandrasekhara

    2012-01-01

    AIM To report various ocular lesions caused by accidental instillation of superglue. METHODS Three cases of ocular injuries are described in children aged 6 years, 3 years and 8 months, following accidental instillation of superglue in the eye. RESULTS In the first case there was sticking of eyelashes in the medial 1/3 of eyelids in both eyes. In the second case sticking of eye lashes was present in the lateral 1/3 of eyelids in the left eye. In the third case, superglue was present on the right cheek, above the right ear and sticking of eyelids in medial 1/3 in right eye. The eyelids were separated by pulling the lid margins with fingers in the first case and later on superglue was removed by trimming the eyelashes; and by direct trimming the eyelashes in second and third cases. There was no injury to other structures of anterior segment in the first two cases. However, removal of the superglue on the cornea resulted in corneal abrasion in the third case which healed with medical treatment and patching of the right eye. CONCLUSION Accidental instillation of superglue is possible because of the appearance of the tube like eye ointment tube. Immediate medical aid will prevent ocular morbidity. PMID:23166877

  1. Noncontact detection of dry eye using a custom designed IR thermal image system

    NASA Astrophysics Data System (ADS)

    Su, Tai Yuan; Chen, Kerh Hwa; Liu, Po Hsuan; Wu, Ming Hong; Chang, David O.; Chiang, Huihua

    2011-03-01

    Dry eye syndrome is a common irritating eye disease. Current clinical diagnostic methods are invasive and uncomfortable to patients. A custom designed noncontact infrared (IR) thermal image system was developed to measure the spatial and temporal variation of the ocular surface temperature over a 6-second eye-opening period. We defined two parameters: the temperature difference value and the compactness value to represent the degree of the temperature change and irregularity of the temperature distribution on the tear film. By using these two parameters, in this study, a linear discrimination result for the dry eye and the normal eye groups; the sensitivity is 0.9, the specificity is 0.86 and the receiver operating characteristic (ROC) area is 0.91. The result suggests that the custom designed IR thermal image system may be used as an effective tool for noncontact detection of dry eye.

  2. Noncontact detection of dry eye using a custom designed infrared thermal image system.

    PubMed

    Su, Tai Yuan; Hwa, Chen Kerh; Liu, Po Hsuan; Wu, Ming Hong; Chang, David O; Su, Po Fang; Chang, Shu Wen; Chiang, Huihua Kenny

    2011-04-01

    Dry eye syndrome is a common irritating eye disease. Current clinical diagnostic methods are invasive and uncomfortable for patients. This study developed a custom designed noncontact infrared (IR) thermal image system to measure the spatial and temporal variation of the ocular surface temperature over a 6-second eye-open period. This research defined two parameters: the temperature difference value and the compactness value to represent the temperature change and the irregularity of the temperature distribution on the tear film. Using these two parameters, this study achieved discrimination results for the dry eye and the normal eye groups; the sensitivity is 0.84, the specificity is 0.83, and the receiver operating characteristic area is 0.87. The results suggest that the custom designed IR thermal image system may be used as an effective tool for noncontact detection of dry eye.

  3. Noncontact detection of dry eye using a custom designed infrared thermal image system

    NASA Astrophysics Data System (ADS)

    Su, Tai Yuan; Hwa, Chen Kerh; Liu, Po Hsuan; Wu, Ming Hong; Chang, David O.; Su, Po Fang; Chang, Shu Wen; Chiang, Huihua Kenny

    2011-04-01

    Dry eye syndrome is a common irritating eye disease. Current clinical diagnostic methods are invasive and uncomfortable for patients. This study developed a custom designed noncontact infrared (IR) thermal image system to measure the spatial and temporal variation of the ocular surface temperature over a 6-second eye-open period. This research defined two parameters: the temperature difference value and the compactness value to represent the temperature change and the irregularity of the temperature distribution on the tear film. Using these two parameters, this study achieved discrimination results for the dry eye and the normal eye groups; the sensitivity is 0.84, the specificity is 0.83, and the receiver operating characteristic area is 0.87. The results suggest that the custom designed IR thermal image system may be used as an effective tool for noncontact detection of dry eye.

  4. Saccadic Eye Movement Characteristics in Adult Niemann-Pick Type C Disease: Relationships with Disease Severity and Brain Structural Measures

    PubMed Central

    Abel, Larry A.; Bowman, Elizabeth A.; Velakoulis, Dennis; Fahey, Michael C.; Desmond, Patricia; Macfarlane, Matthew D.; Looi, Jeffrey Chee Leong; Adamson, Christopher L.; Walterfang, Mark

    2012-01-01

    Niemann-Pick Type C disease (NPC) is a rare genetic disorder of lipid metabolism. A parameter related to horizontal saccadic peak velocity was one of the primary outcome measures in the clinical trial assessing miglustat as a treatment for NPC. Neuropathology is widespread in NPC, however, and could be expected to affect other saccadic parameters. We compared horizontal saccadic velocity, latency, gain, antisaccade error percentage and self-paced saccade generation in 9 adult NPC patients to data from 10 age-matched controls. These saccadic measures were correlated with appropriate MRI-derived brain structural measures (e.g., dorsolateral prefrontal cortex, frontal eye fields, supplemental eye fields, parietal eye fields, pons, midbrain and cerebellar vermis) and with measures of disease severity and duration. The best discriminators between groups were reflexive saccade gain and the two volitional saccade measures. Gain was also the strongest correlate with disease severity and duration. Most of the saccadic measures showed strongly significant correlations with neurophysiologically appropriate brain regions. While our patient sample is small, the apparent specificity of these relationships suggests that as new diagnostic methods and treatments become available for NPC, a broader range of saccadic measures may be useful tools for the assessment of disease progression and treatment efficacy. PMID:23226429

  5. Eyes in the Sky

    NASA Technical Reports Server (NTRS)

    2006-01-01

    These shape-shifting galaxies have taken on the form of a giant mask. The icy blue eyes are actually the cores of two merging galaxies, called NGC 2207 and IC 2163, and the mask is their spiral arms. The false-colored image consists of infrared data from NASA's Spitzer Space Telescope (red) and visible data from NASA's Hubble Space Telescope (blue/green).

    NGC 2207 and IC 2163 met and began a sort of gravitational tango about 40 million years ago. The two galaxies are tugging at each other, stimulating new stars to form. Eventually, this cosmic ball will come to an end, when the galaxies meld into one. The dancing duo is located 140 million light-years away in the Canis Major constellation.

    The infrared data from Spitzer highlight the galaxies' dusty regions, while the visible data from Hubble indicates starlight. In the Hubble-only image (not pictured here), the dusty regions appear as dark lanes.

    The Hubble data correspond to light with wavelengths of .44 and .55 microns (blue and green, respectively). The Spitzer data represent light of 8 microns.

  6. Antiangiogenic Eye Gene Therapy.

    PubMed

    Corydon, Thomas J

    2015-08-01

    The idea of treating disease in humans with genetic material was conceived over two decades ago and with that a promising journey involving development and efficacy studies in cells and animals of a large number of novel therapeutic reagents unfolded. In the footsteps of this process, successful gene therapy treatment of genetic conditions in humans has shown clear signs of efficacy. Notably, significant advancements using gene supplementation and silencing strategies have been made in the field of ocular gene therapy, thereby pinpointing ocular gene therapy as one of the compelling "actors" bringing gene therapy to the clinic. Most of all, this success has been facilitated because of (1) the fact that the eye is an effortlessly accessible, exceedingly compartmentalized, and immune-privileged organ offering a unique advantage as a gene therapy target, and (2) significant progress toward efficient, sustained transduction of cells within the retina having been achieved using nonintegrating vectors based on recombinant adeno-associated virus and nonintegrating lentivirus vectors. The results from in vivo experiments and trials suggest that treatment of inherited retinal dystrophies, ocular angiogenesis, and inflammation with gene therapy can be both safe and effective. Here, the progress of ocular gene therapy is examined with special emphasis on the potential use of RNAi- and protein-based antiangiogenic gene therapy to treat exudative age-related macular degeneration.

  7. Cat eye syndrome

    PubMed Central

    Sharma, Deepak; Murki, Srinivas; Pratap, Tejo; Vasikarla, Madhavi

    2014-01-01

    A full-term female baby, a product of non-consanguineous marriage, was born at 37 weeks of gestation with a birth weight of 2.08 kg. Antenatal scan at 31 weeks revealed complex congenital heart disease with a hypoplastic right ventricle, pulmonary atresia and an intact septum. Immediately after birth, the infant was shifted to the nursery and was started on intravenous fluids and infusion prostaglandin E1 (Alprostidil). On examination, she had microcephaly, periorbital puffiness, a long philtrum, a broad nasal bridge and retrognathia, up slanting palpebral fissures, widely spaced nipples, a sacral dimple and right upper limb postaxial polydactyly. Postnatal echocardiography confirmed a large ostium secundum atrial septal defect with left to right shunt, right ventricle hypoplasia, pulmonary atresia with an intact septum and a large vertical patent ductus arteriosus. Ophthalmological examination showed a bilateral chorioretinal coloboma sparing disc and fovea. Karyotyping showed an extra small marker chromosome suggestive of the Cat eye syndrome. PMID:24842361

  8. Cat eye syndrome.

    PubMed

    Sharma, Deepak; Murki, Srinivas; Pratap, Tejo; Vasikarla, Madhavi

    2014-05-19

    A full-term female baby, a product of non-consanguineous marriage, was born at 37 weeks of gestation with a birth weight of 2.08 kg. Antenatal scan at 31 weeks revealed complex congenital heart disease with a hypoplastic right ventricle, pulmonary atresia and an intact septum. Immediately after birth, the infant was shifted to the nursery and was started on intravenous fluids and infusion prostaglandin E1 (Alprostidil). On examination, she had microcephaly, periorbital puffiness, a long philtrum, a broad nasal bridge and retrognathia, up slanting palpebral fissures, widely spaced nipples, a sacral dimple and right upper limb postaxial polydactyly. Postnatal echocardiography confirmed a large ostium secundum atrial septal defect with left to right shunt, right ventricle hypoplasia, pulmonary atresia with an intact septum and a large vertical patent ductus arteriosus. Ophthalmological examination showed a bilateral chorioretinal coloboma sparing disc and fovea. Karyotyping showed an extra small marker chromosome suggestive of the Cat eye syndrome.

  9. The eyes of LITENING

    NASA Astrophysics Data System (ADS)

    Moser, Eric K.

    2016-05-01

    LITENING is an airborne system-of-systems providing long-range imaging, targeting, situational awareness, target tracking, weapon guidance, and damage assessment, incorporating a laser designator and laser range finders, as well as non-thermal and thermal imaging systems, with multi-sensor boresight. Robust operation is at a premium, and subsystems are partitioned to modular, swappable line-replaceable-units (LRUs) and shop-replaceable-units (SRUs). This presentation will explore design concepts for sensing, data storage, and presentation of imagery associated with the LITENING targeting pod. The "eyes" of LITENING are the electro-optic sensors. Since the initial LITENING II introduction to the US market in the late 90s, as the program has evolved and matured, a series of spiral functional improvements and sensor upgrades have been incorporated. These include laser-illuminated imaging, and more recently, color sensing. While aircraft displays are outside of the LITENING system, updates to the available viewing modules have also driven change, and resulted in increasingly effective ways of utilizing the targeting system. One of the latest LITENING spiral upgrades adds a new capability to display and capture visible-band color imagery, using new sensors. This is an augmentation to the system's existing capabilities, which operate over a growing set of visible and invisible colors, infrared bands, and laser line wavelengths. A COTS visible-band camera solution using a CMOS sensor has been adapted to meet the particular needs associated with the airborne targeting use case.

  10. An Investigation of Horizontal Combined Eye-Head Tracking in Patients with Abnormal Vestibular and Smooth Pursuit Eye Movements

    NASA Technical Reports Server (NTRS)

    Huebner, William P.; Leigh, R. John; Seidman, Scott H.; Billian, Carl

    1993-01-01

    We investigated the interaction of smooth ocular pursuit (SP) and the vestibulo-ocular reflex (VOR) during horizontal, combined eye-head tracking (CEHT) in patients with abnormalities of either the VOR or SP movements. Our strategy was to apply transient stimuli that capitalized on the different latencies to onset of SP and the VOR. During CEHT of a target moving at 15 deg/sec, normal subjects and patients with VOR deficits all tracked the target with a gain close to 1.O. When the heads of normal subjects were suddenly and unexpectedly braked to a halt during CEHT, the eye promptly began to move in the orbit to track the target, but eye-in-orbit velocity transiently fell to about 60-70% of target velocity. In patients with deficient labyrinthine function, following the onset of the head brake, eye movements to track the target were absent, and SP movements were not generated until about 100 msec later. In patients with deficient SP, CEHT was superior to SP tracking with the head stationary; after the onset of the head brake, tracking eye movements were initiated promptly, but eye velocity was less than 50% of target velocity and increased only slightly thereafter. These results indicate that at least two mechanisms operate to overcome the VOR and allow gaze to track the target during CEHT: (1) the SP system provides a signal to cancel a normally-operating VOR (this cancellation signal is not needed by labyrinthine-deficient patients who have no VOR to cancel), and (2) a reduction of the gain of the VOR is achieved, an ability that is preserved even in patients with cerebral lesions that impair SP.

  11. Eye proprioception used for visual localization only if in conflict with the oculomotor plan.

    PubMed

    Balslev, Daniela; Himmelbach, Marc; Karnath, Hans-Otto; Borchers, Svenja; Odoj, Bartholomaeus

    2012-06-20

    Both the corollary discharge of the oculomotor command and eye muscle proprioception provide eye position information to the brain. Two contradictory models have been suggested about how these two sources contribute to visual localization: (1) only the efference copy is used whereas proprioception is a slow recalibrator of the forward model, and (2) both signals are used together as a weighted average. We had the opportunity to test these hypotheses in a patient (R.W.) with a circumscribed lesion of the right postcentral gyrus that overlapped the human eye proprioceptive representation. R.W. was as accurate and precise as the control group (n = 19) in locating a lit LED that she viewed through the eye contralateral to the lesion. However, when the task was preceded by a brief (<1 s), gentle push to the closed eye, which perturbed eye position and stimulated eye proprioceptors in the absence of a motor command, R.W.'s accuracy significantly decreased compared with both her own baseline and the healthy control group. The data suggest that in normal conditions, eye proprioception is not used for visual localization. Eye proprioception is, however, continuously monitored to be incorporated into the eye position estimate when a mismatch with the efference copy of the motor command is detected. Our result thus supports the first model and, furthermore, identifies the limits for its operation.

  12. Microcystic Inner Nuclear Layer Changes and Retinal Nerve Fiber Layer Defects in Eyes with Glaucoma

    PubMed Central

    Hasegawa, Tomoko; Akagi, Tadamichi; Yoshikawa, Munemitsu; Suda, Kenji; Yamada, Hiroshi; Kimura, Yugo; Nakanishi, Hideo; Miyake, Masahiro; Unoki, Noriyuki; Ikeda, Hanako Ohashi; Yoshimura, Nagahisa

    2015-01-01

    Objective To examine microcystic inner nuclear layer (INL) changes in glaucomatous eyes and to determine associated factors. Design Retrospective, cross-sectional, observational study. Methods Two hundred seventeen eyes of 133 patients with primary open angle glaucoma (POAG), 41 eyes of 32 patients with preperimetric glaucoma and 181 normal eyes of 117 subjects were ultimately included. Microcystic INL lesions were examined with infrared fundus images and with 19 vertical spectral domain optical coherence tomography (SD-OCT) images in the macular area. Results Microcystic INL changes were observed in 6.0% of eyes with POAG, but none of the normal eyes or eyes with preperimetric glaucoma showed microcystic INL changes. The proportion of eyes with advanced glaucoma was significantly larger (P = 0.013) in eyes with microcystic lesions than without. The visual field mean deviation (MD) slope was also significantly worse (P = 0.027) in eyes with microcystic lesions. No significant differences were observed in age, sex, refraction, axial length, intraocular pressure, or MD value between eyes with and without microcystic INL lesions. In several cases, microcystic INL lesions occurred along with glaucomatous visual field progression. The retinal nerve fiber layer (RNFL) thickness (P = 0.013) and ganglion cell layer (GCL) + inner plexiform layer thickness (P = 0.023) were significantly lower in areas with microcystic lesions than without. The INL was also significantly thicker (P = 0.002) in areas with microcystic lesions. Conclusions Microcystic INL lesions in glaucomatous eyes are closely associated with RNFL and GCL thinning and correlated with worse MD slope. These INL lesions may indicate focal and progressive damage in glaucoma. PMID:26066021

  13. Effect of gravity on vertical eye position.

    PubMed

    Pierrot-Deseilligny, C

    2009-05-01

    There is growing evidence that gravity markedly influences vertical eye position and movements. A new model for the organization of brainstem upgaze pathways is presented in this review. The crossing ventral tegmental tract (CVTT) could be the efferent tract of an "antigravitational" pathway terminating at the elevator muscle motoneurons in the third nerve nuclei and comprising, upstream, the superior vestibular nucleus and y-group, the flocculus, and the otoliths. This pathway functions in parallel to the medial longitudinal fasciculus pathways, which control vertical eye movements made to compensate for all vertical head movements and may also comprise the "gravitational" vestibular pathways, involved in the central reflection of the gravity effect. The CVTT could provide the upgaze system with the supplement of tonic activity required to counteract the gravity effect expressed in the gravitational pathway, being permanently modulated according to the static positions of the head (i.e., the instantaneous gravity vector) between a maximal activity in the upright position and a minimal activity in horizontal positions. Different types of arguments support this new model. The permanent influence of gravity on vertical eye position is strongly suggested by the vertical slow phases and nystagmus observed after rapid changes in hypo- or hypergravity. The chin-beating nystagmus, existing in normal subjects with their head in the upside-down position, suggests that gravity is not compensated for in the downgaze system. Upbeat nystagmus due to brainstem lesions, most likely affecting the CVTT circuitry, is improved when the head is in the horizontal position, suggesting that this circuitry is involved in the counteraction of gravity between the upright and horizontal positions of the head. In downbeat nystagmus due to floccular damage, in which a permanent hyperexcitation of the CVTT could exist, a marked influence of static positions of the head is also observed. Finally

  14. Neurological Basis for Eye Movements of the Blind

    PubMed Central

    Schneider, Rosalyn M.; Thurtell, Matthew J.; Eisele, Sylvia; Lincoff, Norah; Bala, Elisa; Leigh, R. John

    2013-01-01

    When normal subjects fix their eyes upon a stationary target, their gaze is not perfectly still, due to small movements that prevent visual fading. Visual loss is known to cause greater instability of gaze, but reported comparisons with normal subjects using reliable measurement techniques are few. We measured binocular gaze using the magnetic search coil technique during attempted fixation (monocular or binocular viewing) of 4 individuals with childhood-onset of monocular visual loss, 2 individuals with late-onset monocular visual loss due to age-related macular degeneration, 2 individuals with bilateral visual loss, and 20 healthy control subjects. We also measured saccades to visual or somatosensory cues. We tested the hypothesis that gaze instability following visual impairment is caused by loss of inputs that normally optimize the performance of the neural network (integrator), which ensures both monocular and conjugate gaze stability. During binocular viewing, patients with early-onset monocular loss of vision showed greater instability of vertical gaze in the eye with visual loss and, to a lesser extent, in the normal eye, compared with control subjects. These vertical eye drifts were much more disjunctive than upward saccades. In individuals with late monocular visual loss, gaze stability was more similar to control subjects. Bilateral visual loss caused eye drifts that were larger than following monocular visual loss or in control subjects. Accurate saccades could be made to somatosensory cues by an individual with acquired blindness, but voluntary saccades were absent in an individual with congenital blindness. We conclude that the neural gaze-stabilizing network, which contains neurons with both binocular and monocular discharge preferences, is under adaptive visual control. Whereas monocular visual loss causes disjunctive gaze instability, binocular blindness causes both disjunctive and conjugate gaze instability (drifts and nystagmus). Inputs that

  15. Conjunctivitis (Pink Eye) in Newborns

    MedlinePlus

    ... Get Smart: Know When Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal Conjunctivitis (Pink Eye) in Newborns ... Get Smart: Know When Antibiotics Work Adenovirus Non-Polio Enterovirus Parent Portal Language: English Español (Spanish) File ...

  16. Applications of lobster eye optics

    NASA Astrophysics Data System (ADS)

    Hudec, R.; Pina, L.; Inneman, A.; Tichy, V.

    2015-05-01

    Applications of wide field Lobster Eye X ray telescopes are presented and discussed. The wide field X ray optics was originally proposed for use in X-ray astronomy, but there are numerous other application areas as well.

  17. Eye movements when viewing advertisements

    PubMed Central

    Higgins, Emily; Leinenger, Mallorie; Rayner, Keith

    2013-01-01

    In this selective review, we examine key findings on eye movements when viewing advertisements. We begin with a brief, general introduction to the properties and neural underpinnings of saccadic eye movements. Next, we provide an overview of eye movement behavior during reading, scene perception, and visual search, since each of these activities is, at various times, involved in viewing ads. We then review the literature on eye movements when viewing print ads and warning labels (of the kind that appear on alcohol and tobacco ads), before turning to a consideration of advertisements in dynamic media (television and the Internet). Finally, we propose topics and methodological approaches that may prove to be useful in future research. PMID:24672500

  18. Obtaining consent for eye donation.

    PubMed

    Diamond, G A; Campion, M; Mussoline, J F; D'Amico, R A

    1987-02-15

    We prospectively studied 100 consecutive deaths at St. Vincent's Hospital and Medical Center in New York City for possible eye donation. Fifty-two patients were unsuitable mainly because of medical contraindications and age at death. Of the 48 suitable candidates, 21 pairs (44%) of eyes were obtained. Sixteen of the 42 eyes (38%) were used for transplantation. Projection of the number of corneas obtainable for transplant in New York City were calculated. The figures indicated that the three-month waiting list of the New York Eye-Bank for Sight Restoration, Inc., could be eradicated if hospitals were able to get seven donors from every 100 deaths suitable for donation, a rate only 16% of that realized in this study.

  19. Basics of LASIK Eye Surgery

    MedlinePlus

    ... the shape of the cornea and compromise precise measurements in the pre-op exam. Your doctor should: ... and assessing for dry eye take the following measurements: the curvature of your cornea and your pupils ...

  20. Genetic Testing and Eye Disease

    MedlinePlus

    ... a History of Eye Disease, Do You Need Genetic Testing? Mar. 23, 2012 Thanks to news coverage, ... of breast or ovarian cancer. Physicians now use genetic tests to decide on treatment for some types ...

  1. Finding an Eye Care Professional

    MedlinePlus

    ... Courier services use: Rockville, MD 20852) 301-451-2020 Research at NEI Office of the Scientific Director ... Eye Disease Education Program Glaucoma Education Program Low Vision Education Program Hispanic/Latino Program Vision and Aging ...

  2. Eyes: variety, development and evolution.

    PubMed

    Fernald, Russell D

    2004-01-01

    The selective advantages of using light as a source of information are reflected in the diverse types of extant eyes. The physical properties of light restrict how it can be collected and processed, resulting in only eight known optical systems found in animals. Eyes develop through tissue rearrangement and differentiation. Our understanding of the source of genetic information used in developmental programs is growing rapidly and reveals distributions of gene expression with substantial overlap in both time and space. Specific genes and their products are used repeatedly, making causal relationships more difficult to discern. The phenomenon of groups of genes acting together seems to be the rule. Throughout evolution, particular genes have become associated with distinct aspects of eye development, and these suites of genes have been recruited repeatedly as new eyes evolved.

  3. CYANOACRYLATE ADHESIVES IN EYE WOUNDS.

    DTIC Science & Technology

    adhesives. The following adhesives were tested: methyl, isobutyl, n-butyl, n-hexyl, n-heptyl, n-octyl, n-decyl, -trifluoroisopropyl 2- cyanoacrylate , and...Biobond. Of these, methyl and -trifluoroisopropyl cyanoacrylates are not well tolerated by eye tissues. Biobond sets too slowly, and does not seem... cyanoacrylate is the best adhesive found so far when tissue tolerance, tensile strength, and ability to seal eye perforations (alone and with silicone rubber patches) are the criteria. (Author)

  4. Eye-voice-controlled interface

    NASA Technical Reports Server (NTRS)

    Glenn, Floyd A., III; Iavecchia, Helene P.; Ross, Lorna V.; Stokes, James M.; Weiland, William J.

    1986-01-01

    The Ocular Attention-Sensing Interface System (OASIS) is an innovative human-computer interface which utilizes eye movement and voice commands to communicate messages between the operator and the system. This report initially describes some technical issues relevant to the development of such an interface. The results of preliminary experiments which evaluate alternative eye processing algorithms and feedback techniques are presented. Candidate interface applications are also discussed.

  5. Electroporation of Embryonic Chick Eyes

    PubMed Central

    Luz-Madrigal, Agustín; Grajales-Esquivel, Erika; Del Rio-Tsonis, Katia

    2016-01-01

    The chick embryo has prevailed as one of the major models to study developmental biology, cell biology and regeneration. From all the anatomical features of the chick embryo, the eye is one of the most studied. In the chick embryo, the eye develops between 26 and 33 h after incubation (Stages 8–9, Hamburger and Hamilton, 1951). It originates from the posterior region of the forebrain, called the diencephalon. However, the vertebrate eye includes tissues from different origins including surface ectoderm (lens and cornea), anterior neural plate (retina, iris, ciliary body and retinal pigmented epithelium) and neural crest/head mesoderm (stroma of the iris and of the ciliary body as well as choroid, sclera and part of the cornea). After gastrulation, a single eye field originates from the anterior neural plate and is characterized by the expression of eye field transcriptional factors (EFTFs) that orchestrate the program for eye development. Later in development, the eye field separates in two and the optic vesicles form. After several inductive interactions with the lens placode, the optic cup forms. At Stages 14–15, the outer layer of the optic cup becomes the retinal pigmented epithelium (RPE) while the inner layer forms the neuroepithelium that eventually differentiates into the retina. One main advantage of the chick embryo, is the possibility to perform experiments to over-express or to down-regulate gene expression in a place and time specific manner to explore gene function and regulation. The aim of this protocol is to describe the electroporation techniques at Stages 8–12 (anterior neural fold and optic vesicle stages) and Stages 19–26 (eye cup, RPE and neuroepithelium). We provide a full description of the equipment, materials and electrode set up as well as a detailed description of the highly reproducible protocol including some representative results. This protocol has been adapted from our previous publications Luz-Madrigal et al. (2014) and Zhu

  6. The Cat's Eye Nebula

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This NASA Hubble Space Telescope image shows one of the most complex planetary nebulae ever seen, NGC 6543, nicknamed the 'Cat's Eye Nebula.' Hubble reveals surprisingly intricate structures including concentric gas shells, jets of high-speed gas and unusual shock-induced knots of gas. Estimated to be 1,000 years old, the nebula is a visual 'fossil record' of the dynamics and late evolution of a dying star. A preliminary interpretation suggests that the star might be a double-star system. The suspected companion star also might be responsible for a pair of high-speed jets of gas that lie at right angles to this equatorial ring. If the companion were pulling in material from a neighboring star, jets escaping along the companion's rotation axis could be produced. These jets would explain several puzzling features along the periphery of the gas lobes. Like a stream of water hitting a sand pile, the jets compress gas ahead of them, creating the 'curlicue' features and bright arcs near the outer edge of the lobes. The twin jets are now pointing in different directions than these features. This suggests the jets are wobbling, or precessing, and turning on and off episodically. This color picture, taken with the Wide Field Planetary Camera-2, is a composite of three images taken at different wavelengths. (red, hydrogen-alpha; blue, neutral oxygen, 6300 angstroms; green, ionized nitrogen, 6584 angstroms). The image was taken on September 18, 1994. NGC 6543 is 3,000 light- years away in the northern constellation Draco. The term planetary nebula is a misnomer; dying stars create these cocoons when they lose outer layers of gas. The process has nothing to do with planet formation, which is predicted to happen early in a star's life.

  7. Eye Movements in Risky Choice

    PubMed Central

    Hermens, Frouke; Matthews, William J.

    2015-01-01

    Abstract We asked participants to make simple risky choices while we recorded their eye movements. We built a complete statistical model of the eye movements and found very little systematic variation in eye movements over the time course of a choice or across the different choices. The only exceptions were finding more (of the same) eye movements when choice options were similar, and an emerging gaze bias in which people looked more at the gamble they ultimately chose. These findings are inconsistent with prospect theory, the priority heuristic, or decision field theory. However, the eye movements made during a choice have a large relationship with the final choice, and this is mostly independent from the contribution of the actual attribute values in the choice options. That is, eye movements tell us not just about the processing of attribute values but also are independently associated with choice. The pattern is simple—people choose the gamble they look at more often, independently of the actual numbers they see—and this pattern is simpler than predicted by decision field theory, decision by sampling, and the parallel constraint satisfaction model. © 2015 The Authors. Journal of Behavioral Decision Making published by John Wiley & Sons Ltd. PMID:27522985

  8. The eye and the heart

    PubMed Central

    Flammer, Josef; Konieczka, Katarzyna; Bruno, Rosa M.; Virdis, Agostino; Flammer, Andreas J.; Taddei, Stefano

    2013-01-01

    The vasculature of the eye and the heart share several common characteristics. The easily accessible vessels of the eye are therefore—to some extent—a window to the heart. There is interplay between cardiovascular functions and risk factors and the occurrence and progression of many eye diseases. In particular, arteriovenous nipping, narrowing of retinal arteries, and the dilatation of retinal veins are important signs of increased cardiovascular risk. The pressure in the dilated veins is often markedly increased due to a dysregulation of venous outflow from the eye. Besides such morphological criteria, functional alterations might be even more relevant and may play an important role in future diagnostics. Via neurovascular coupling, flickering light dilates capillaries and small arterioles, thus inducing endothelium-dependent, flow-mediated dilation of larger retinal vessels. Risk factors for arteriosclerosis, such as dyslipidaemia, diabetes, or systemic hypertension, are also risk factors for eye diseases such as retinal arterial or retinal vein occlusions, cataracts, age-related macular degeneration, and increases in intraocular pressure (IOP). Functional alterations of blood flow are particularly relevant to the eye. The primary vascular dysregulation syndrome (PVD), which often includes systemic hypotension, is associated with disturbed autoregulation of ocular blood flow (OBF). Fluctuation of IOP on a high level or blood pressure on a low level leads to instable OBF and oxygen supply and therefore to oxidative stress, which is particularly involved in the pathogenesis of glaucomatous neuropathy. Vascular dysregulation also leads to a barrier dysfunction and thereby to small retinal haemorrhages. PMID:23401492

  9. Effects of antiglaucoma drugs on blood supply to eye tissues

    SciTech Connect

    Chiou, G.C.Y.; Yan, H.Y.

    1986-03-01

    Although it is essential that intraocular pressure (IOP) be reduced in glaucoma treatment, it is also vitally important to provide sufficient blood flow to eye tissues so that healthy visual field is maintained. It is possible for an agent to reduce IOP and blood supply to the eye. In that case, glaucoma appears to be under control since IOP has been reduced to within normal range yet the disease is actually progressing, causing damage to the retina, optic nerve, and other tissues. /sup 85/Sr-Microsphere technique was used to study the effects of several antiglaucoma drugs on blood supply to various eye tissues. Clearly, L-timolol, D-timolol and pilocarpine are good drugs to use in treating glaucoma because they do not reduce blood flow. On the other hand, although moperone reduced IOP effectively, it also decreased blood supply markedly. Therefore, it should not be used for the treatment of glaucoma.

  10. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  11. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  12. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  13. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  14. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  15. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  16. 21 CFR 886.3200 - Artificial eye.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion of the eye, usually made of glass or plastic, intended to...

  17. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  18. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  19. 21 CFR 886.3200 - Artificial eye.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion of the eye, usually made of glass or plastic, intended to...

  20. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  1. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  2. 21 CFR 878.4440 - Eye pad.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Eye pad. 878.4440 Section 878.4440 Food and Drugs... GENERAL AND PLASTIC SURGERY DEVICES Surgical Devices § 878.4440 Eye pad. (a) Identification. An eye pad is... use as a bandage over the eye for protection or absorption of secretions. (b) Classification. Class...

  3. 21 CFR 886.3200 - Artificial eye.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion of the eye, usually made of glass or plastic, intended to...

  4. 21 CFR 886.3200 - Artificial eye.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion of the eye, usually made of glass or plastic, intended to...

  5. 14 CFR 67.303 - Eye.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Eye. 67.303 Section 67.303 Aeronautics and... AND CERTIFICATION Third-Class Airman Medical Certificate § 67.303 Eye. Eye standards for a third-class airman medical certificate are: (a) Distant visual acuity of 20/40 or better in each eye separately,...

  6. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  7. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  8. 21 CFR 886.3200 - Artificial eye.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and... OPHTHALMIC DEVICES Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion of the eye, usually made of glass or plastic, intended to...

  9. 14 CFR 67.103 - Eye.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Eye. 67.103 Section 67.103 Aeronautics and... AND CERTIFICATION First-Class Airman Medical Certificate § 67.103 Eye. Eye standards for a first-class airman medical certificate are: (a) Distant visual acuity of 20/20 or better in each eye separately,...

  10. A New Method to Assess Eye Dominance

    ERIC Educational Resources Information Center

    Valle-Inclan, Fernando; Blanco, Manuel J.; Soto, David; Leiros, Luz

    2008-01-01

    People usually show a stable preference for one of their eyes when monocular viewing is required ("sighting dominance") or under dichoptic stimulation conditions ("sensory eye-dominance"). Current procedures to assess this "eye dominance" are prone to error. Here we present a new method that provides a continuous measure of eye dominance and…

  11. Contact Lens-Related Eye Infections

    MedlinePlus

    ... Stories Español Eye Health / Eye Health A-Z Contact Lens-Related Eye Infections Sections Contact Lens-Related ... About Contact Lenses Proper Care of Contact Lenses Contact Lens-Related Eye Infections Written by: Kierstan Boyd ...

  12. Rethinking dry eye disease: a perspective on clinical implications.

    PubMed

    Bron, Anthony J; Tomlinson, Alan; Foulks, Gary N; Pepose, Jay S; Baudouin, Christophe; Geerling, Gerd; Nichols, Kelly K; Lemp, Michael A

    2014-04-01

    Publication of the DEWS report in 2007 established the state of the science of dry eye disease (DED). Since that time, new evidence suggests that a rethinking of traditional concepts of dry eye disease is in order. Specifically, new evidence on the epidemiology of the disease, as well as strategies for diagnosis, have changed the understanding of DED, which is a heterogeneous disease associated with considerable variability in presentation. These advances, along with implications for clinical care, are summarized herein. The most widely used signs of DED are poorly correlated with each other and with symptoms. While symptoms are thought to be characteristic of DED, recent studies have shown that less than 60% of subjects with other objective evidence of DED are symptomatic. Thus the use of symptoms alone in diagnosis will likely result in missing a significant percentage of DED patients, particularly with early/mild disease. This could have considerable impact in patients undergoing cataract or refractive surgery as patients with DED have less than optimal visual results. The most widely used objective signs for diagnosing DED all show greater variability between eyes and in the same eye over time compared with normal subjects. This variability is thought to be a manifestation of tear film instability which results in rapid breakup of the tearfilm between blinks and is an identifier of patients with DED. This feature emphasizes the bilateral nature of the disease in most subjects not suffering from unilateral lid or other unilateral destabilizing surface disorders. Instability of the composition of the tears also occurs in dry eye disease and shows the same variance between eyes. Finally, elevated tear osmolarity has been reported to be a global marker (present in both subtypes of the disease- aqueous-deficient dry eye and evaporative dry eye). Clinically, osmolarity has been shown to be the best single metric for diagnosis of DED and is directly related to

  13. A thermographic study on eyes affected by Age-related Macular Degeneration: Comparison among various forms of the pathology and analysis of risk factors

    NASA Astrophysics Data System (ADS)

    Matteoli, Sara; Finocchio, Lucia; Biagini, Ilaria; Giacomelli, Giovanni; Sodi, Andrea; Corvi, Andrea; Virgili, Gianni; Rizzo, Stanislao

    2016-05-01

    The aims of this study are to investigate (1) the ocular thermographic profiles in eyes affected by Age related Macular Degeneration (AMD) and age-matched controls to detect possible hemodynamic abnormalities that could be involved in the pathogenesis of the disease, (2) whether any risk factors associated with the disease could affect the development of a form of AMD rather than another. Thirty-four eyes with Age-Related Maculopathy (ARM), 41 eyes with dry AMD, 60 eyes affected by wet AMD, and 74 eyes with fibrotic AMD were included in the study. The control group consisted of 48 healthy eyes. Exclusion criteria were represented by any other ocular diseases other than AMD, tear film abnormalities, systemic cardiovascular abnormalities, systemic diseases and a body temperature higher than 37.5 °C. A total of 210 eyes without pupil dilation were investigated by infrared thermography (FLIR A320). The Ocular Surface Temperature (OST) of five ocular areas was calculated by means of an image processing technique from the infrared images. Two-sample t-test, one-way ANOVA test and multivariate analysis were used for statistical analyses. ANOVA analyses showed no significant differences among AMD groups (P-value > 0.05), however, OST in AMD patients was significantly lower than in controls (P-value < 0.0001). Smokers showed higher possibility (P-value = 0.012) of developing wet AMD instead of dry AMD. Infrared thermography may be a helpful, non-invasive and not time-consuming method to be used in the management of patients with this common degenerative maculopathy.

  14. Mucins in contact lens wear and dry eye conditions.

    PubMed

    Ramamoorthy, Padmapriya; Nichols, Jason J

    2008-08-01

    Ocular mucins are thought to play integral roles in ocular surface lubrication, anchoring of the aqueous, stabilizing the lipid components of the tear film, eliminating foreign bodies and pathogens, and with potential involvement in cell cycle mediation and apoptotic activity of ocular surface epithelia. Ocular mucins are of secreted and membrane-associated types. Secreted mucins may be of large gel-forming type or small soluble mucins (e.g., MUC5AC and MUC7). Membrane-associated mucins such as MUCs 1 and 4 are a major component of the glycocalyx. They are thought to render structural support to the microplicae and mediate epithelial cell cycle and apoptotic activity. The alterations in ocular mucins with contact lens wear are unclear. Recent work shows mucin expression may be up-regulated during the early years of contact lens wear, and with long-term lens wear, mucin expression may return to normal levels or sub-normal levels, although this is not well understood. Further, the polar nature of mucins may be associated with their affinity for contact lens surfaces making them a component of contact lens deposition. This has potential implications in the wettability and tolerability of contact lenses, and may be impacted by surface coatings, polymer characteristics, or care solutions. Conjunctival mucin gene expression and secretion may be deficient in several ocular surface disorders associated with dry eye. Deficiency and alterations in glycosylation characteristics of MUC5AC and MUC2 have been reported in both Sjögren and non-Sjögren dry eye types. Decreased binding of the membrane-associated mucin MUC16 to the conjunctival epithelium has been reported in Sjögren dry eye while MUC1 alterations have been reported in Sjögren and non-Sjögren dry eye states. In view of the mucin involvement in dry eye conditions, stimulation of mucus secretion pathways may hold promise in the pharmaceutical treatment of dry eye.

  15. Fluorophotometry as a diagnostic tool for the evaluation of dry eye disease

    PubMed Central

    Fahim, Magid M; Haji, Shamim; Koonapareddy, Chakravarthy V; Fan, Vincent C; Asbell, Penny A

    2006-01-01

    Background Dry eye disease is a common debilitating ocular disease. Current diagnostic tests used in dry eye disease are often neither sensitive nor reproducible, making it difficult to accurately diagnose and determine end points for clinical trials, or evaluate the usefulness of different medications in the treatment of dry eye disease. The recently developed fluorophotometer can objectively detect changes in the corneal epithelium by quantitatively measuring its barrier function or permeability. The purpose of the study is to investigate the use of corneal fluorescein penetration measured by the fluorophotometer as a diagnostic tool in the evaluation of dry eye patients. Methods Dry eye patients (16 eyes), who presented with a chief complaint of ocular irritation corresponding with dry eye, low Schirmer's one test (<10 mm after 5 minutes) and corneal fluorescein staining score of more than two, were included in the study. Normal subjects (16 eyes), who came for refraction error evaluation, served as controls. Institutional Review Board (IRB) approved consent was obtained before enrolling the subjects in the study and all questions were answered while explaining the risks, benefits and alternatives. All Fluorophotometry of the central corneal epithelium was done utilizing the Fluorotron Master (TradeMark). Each eye had a baseline fluorescein scan performed, after which 50 l of 1% sodium fluorescein dye was instilled. Three minutes later, the fluorescein was washed with 50 ml of normal saline. Fluorescein scans were then started immediately after washing and were recorded at 10, 20, 40, and 60 minutes thereafter. The corneal peak values of fluorescein concentration were recorded within the central cornea in both dry eyes and in controls. Results Ten minutes after fluorescein installition, patients with dry eye disease averaged a five-fold increase in corneal tissue fluorescein concentration (mean = 375.26 ± 202.67 ng/ml) compared with that of normal subjects

  16. Eye mechanics and their implications for eye movement control

    NASA Astrophysics Data System (ADS)

    Koene, Ansgar Roald

    2002-11-01

    The topic of this thesis is the investigation of the mechanical properties of the oculomotor system and the implications of these properties for eye movement control. The investigation was conducted by means of computer models and simulations. This allowed us to combine data from anatomy, physiology and psychophysics with basic principles of physics (mechanics) and mathematics (geometry). In chapter 2 we investigate the degree to which mechanical and neural non-linearities contribute to the kinematic differences between centrifugal and centripetal saccades. On the basis of the velocity profiles of centrifugal and centripetal saccades we calculate the forces and muscle innervations during these eye movements. This was done using an inverted model of the eye plant. Our results indicate that the non-linear force-velocity relationship (i.e. muscle viscosity) of the muscles is probably the cause of the kinematic differences between centrifugal and centripetal saccades. In chapter 3 we calculate the adjustment of the saccadic command that is necessary to compensate for the eye plant non-linearities. These calculations show that the agonist and antagonist muscles require different net saccade signal gain changes. In order to better understand how this gain change is accomplished we use the inverted model of the eye plant (chapter 2) to calculate the muscle innervation profiles of saccades with different starting orientations. Based on these calculations we conclude that the saccade signal gain changes are accomplished primarily by changes in the magnitude of the saccade signal. In chapter 4 we examine the requirements that the oculomotor system must meet for the eye to be able to make desired gaze changes and fixate at various eye orientations. We first determine how the axes of action (i.e. unit moment vectors) of the muscles are related to eye orientation and the location of the effective muscle origin (i.e. the muscle pulleys). Next we show how this relation constrains

  17. Posterior Vitreous Detachment With Microplasmin Alters the Retinal Penetration of Intravitreal Bevacizumab (Avastin) in Rabbit Eyes

    PubMed Central

    Goldenberg, David T.; Giblin, Frank J.; Cheng, Mei; Chintala, Shravan K.; Trese, Michael T.; Drenser, Kimberly A.; Ruby, Alan J.

    2010-01-01

    . At three days, one rabbit showed increased antibody labeling in the retina of the non-MP-injected eye compared with the contralateral MP-injected eye, and two rabbits exhibited similar antibody labeling in both eyes. When compared with control eyes, light microscopy demonstrated normal retinal histologic findings in eyes injected only with microplasmin. Conclusions Increased BV retinal penetration is observed initially in eyes with a MP-induced PVD, and the mechanism is likely multifactorial. By three days, retinal penetration is similar in eyes with and without a PVD. Although it is difficult to directly extrapolate to humans, our study suggests a PVD may alter the retinal penetration of BV. PMID:21099453

  18. A novel nanoscale-dispersed eye ointment for the treatment of dry eye disease

    NASA Astrophysics Data System (ADS)

    Zhang, Wenjian; Wang, Yan; Lee, Benjamin Tak Kwong; Liu, Chang; Wei, Gang; Lu, Weiyue

    2014-03-01

    A novel nanoscale-dispersed eye ointment (NDEO) for the treatment of severe evaporative dry eye has been successfully developed. The excipients used as semisolid lipids were petrolatum and lanolin, as used in conventional eye ointment, which were coupled with medium-chain triglycerides (MCT) as a liquid lipid; both phases were then dispersed in polyvinyl pyrrolidone solution to form a nanodispersion. Single-factor experiments were conducted to optimize the formulations. A transmission electron micrograph showed that the ointment matrix was entrapped in the nanoemulsion of MCT, with a mean particle size of about 100 nm. The optimized formulation of NDEO was stable when stored for six months at 4 °C, and demonstrated no cytotoxicity to human corneal epithelial cells when compared with commercial polymer-based artificial tears (Tears Natural® Forte). The therapeutic effects of NDEO were evaluated on a mouse model with ‘dry eye’. Both the tear break-up time and fluorescein staining demonstrated therapeutic improvement, displaying a trend of positive correlation with higher concentrations of ointment matrix in the NDEO formulations compared to a marketed product. Histological evaluation demonstrated that the NDEO restored the normal corneal and conjunctival morphology and is safe for ophthalmic application.

  19. DEBS – a unification theory for dry eye and blepharitis

    PubMed Central

    Rynerson, James M; Perry, Henry D

    2016-01-01

    For many years, blepharitis and dry eye disease have been thought to be two distinct diseases, and evaporative dry eye distinct from aqueous insufficiency. In this treatise, we propose a new way of looking at dry eye, both evaporative and insufficiency, as the natural sequelae of decades of chronic blepharitis. Dry eye is simply the late form and late manifestation of one disease, blepharitis. We suggest the use of a new term in describing this one chronic disease, namely dry eye blepharitis syndrome (DEBS). Bacteria colonize the lid margin within a structure known as a biofilm. The biofilm allows for population densities that initiate quorum-sensing gene activation. These newly activated gene products consist of inflammatory virulence factors, such as exotoxins, cytolytic toxins, and super-antigens, which are then present for the rest of the patient’s life. The biofilm never goes away; it only thickens with age, producing increasing quantities of bacterial virulence factors, and thus, increasing inflammation. These virulence factors are likely the culprits that first cause follicular inflammation, then meibomian gland dysfunction, aqueous insufficiency, and finally, after many decades, lid destruction. We suggest that there are four stages of DEBS which correlate with the clinical manifestations of folliculitis, meibomitis, lacrimalitis, and finally lid structure damage evidenced by entropion, ectropion, and floppy eyelid syndrome. When one fully understands the structure and location of the glands within the lid, it becomes easy to understand this staged disease process. The longer a gland can resist the relentless encroachment of the invading biofilm, the longer it can maintain normal function. The stages depend purely on anatomy and years of biofilm presence. Dry eye now becomes a very easy disease to understand. We feel that dry eye should be treated and prevented by early and routine biofilm removal through electromechanical lid margin debridement. PMID

  20. Drugs affecting the eye.

    PubMed

    Taylor, F

    1985-08-01

    This discussion reviews drugs that affect the eye, including antihyperglycemic agents; corticosteroids; antirheumatic drugs (quinolines, indomethacin, and allopurinol); psychiatric drugs (phenothiazine, thioridazine, and chlorpromazine); drugs used in cardiology (practolol, amiodarone, and digitalis gylcosides); drugs implicated in optic neuritis and atrophy, drugs with an anticholinergic action; oral contraceptives (OCs); and topical drugs and systemic effects. Refractive changes, either myopic or hypermetropic, can occur as a result of hyperglycemia, and variation in vision is sometimes a presenting symptom in diabetes mellitus. If it causes a change in the refraction, treatment of hyperglycemia almost always produces a temporary hypermetropia. A return to the original refractive state often takes weeks, sometimes months. There is some evidence that patients adequately treated with insulin improve more rapidly than those taking oral medication. Such patients always should be referred for opthalmological evaluation as other factors might be responsible, but it might not be possible to order the appropriate spectacle correction for some time. The most important ocular side effect of the systemic adiministration of corticosteroids is the formation of a posterior subcapsular cataract. Glaucoma also can result from corticosteroids, most often when they are applied topically. Corticosteroids have been implicated in the production of benign intracranial hypertension, which is paradoxical because they also are used in its treatment. The most important side effect of drugs such as chloroquine and hydroxychloroquine is an almost always irreversible maculopathy with resultant loss of central vision. Corneal and retinal changes similar to those caused by the quinolines have been reported with indomethacin, but there is some question about a cause and effect relationship. The National Registry of Drug Induced Ocular Side Effects in the US published 30 case histories of

  1. Impaired fixation to eyes following amygdala damage arises from abnormal bottom-up attention.

    PubMed

    Kennedy, Daniel P; Adolphs, Ralph

    2010-10-01

    SM is a patient with complete bilateral amygdala lesions who fails to fixate the eyes in faces and is consequently impaired in recognizing fear (Adolphs et al., 2005). Here we first replicated earlier findings in SM of reduced gaze to the eyes when seen in whole faces. Examination of the time course of fixations revealed that SM's reduced eye contact is particular pronounced in the first fixation to the face, and less abnormal in subsequent fixations. In a second set of experiments, we used a gaze-contingent presentation of faces with real time eye tracking, wherein only a small region of the face is made visible at the center of gaze. In essence, viewers explore the face by moving a small searchlight over the face with their gaze. Under such viewing conditions, SM's fixations to eye region of faces became entirely normalized. We suggest that this effect arises from the absence of bottom-up effects due to the facial features, allowing gaze location to be driven entirely by top-down control. Together with SM's failure to fixate the eyes in whole faces primarily at the very first saccade, the findings suggest that the saliency of the eyes normally attract our gaze in an amygdala-dependent manner. Impaired eye gaze is also a prominent feature of several psychiatric illnesses in which the amygdala has been hypothesized to be dysfunctional, and our findings and experimental manipulation may hold promise for interventions in such populations, including autism and fragile X syndrome.

  2. The perception of heading during eye movements

    NASA Technical Reports Server (NTRS)

    Royden, Constance S.; Banks, Martin S.; Crowell, James A.

    1992-01-01

    Warren and Hannon (1988, 1990), while studying the perception of heading during eye movements, concluded that people do not require extraretinal information to judge heading with eye/head movements present. Here, heading judgments are examined at higher, more typical eye movement velocities than the extremely slow tracking eye movements used by Warren and Hannon. It is found that people require extraretinal information about eye position to perceive heading accurately under many viewing conditions.

  3. Effect of change in macular birefringence imaging protocol on retinal nerve fiber layer thickness parameters using GDx VCC in eyes with macular lesions.

    PubMed

    Dada, Tanuj; Tinwala, Sana I; Dave, Vivek; Agarwal, Anand; Sharma, Reetika; Wadhwani, Meenakshi

    2014-08-01

    This study evaluates the effect of two macular birefringence protocols (bow-tie retardation and irregular macular scan) using GDx VCC on the retinal nerve fiber layer (RNFL) thickness parameters in normal eyes and eyes with macular lesions. In eyes with macular lesions, the standard protocol led to significant overestimation of RNFL thickness which was normalized using the irregular macular pattern protocol. In eyes with normal macula, absolute RNFL thickness values were higher in irregular macular pattern protocols with the difference being statistically significant for all parameters except for inferior average thickness. This has implications for monitoring glaucoma patients who develop macular lesions during the course of their follow-up.

  4. Reading strategies in mild to moderate strabismic amblyopia: an eye movement investigation.

    PubMed

    Kanonidou, Evgenia; Proudlock, Frank A; Gottlob, Irene

    2010-07-01

    PURPOSE. To investigate oculomotor strategies in strabismic amblyopia and evaluate abnormalities during monocular and binocular reading. METHODS. Eye movements were recorded with a head-mounted infrared video eye-tracker (250 Hz, <0.01 degrees resolution) in 20 strabismic amblyopes (mean age, 44.9 +/- 10.7 years) and 20 normal control subjects (mean age, 42.8 +/- 10.9 years) while they silently read paragraphs of text. Monocular reading comparisons were made between the amblyopic eye and the nondominant eye of control subjects and the nonamblyopic eye and the dominant eye of the control subjects. Binocular reading between the amblyopic and control subjects was also compared. RESULTS. Mean reading speed, number of progressive and regressive saccades per line, saccadic amplitude (of progressive saccades), and fixation duration were estimated. Inter- and intrasubject statistical comparisons were made. Reading speed was significantly slower in amblyopes than in control subjects during monocular reading with amblyopic (13.094 characters/s vs. 22.188 characters/s; P < 0.0001) and nonamblyopic eyes (16.241 characters/s vs. 22.349 characters/s, P < 0.0001), and binocularly (15.698 characters/s vs. 23.425 characters/s, P < 0.0001). In amblyopes, reading was significantly slower with the amblyopic eye than with the nonamblyopic eye in binocular viewing (P < 0.05). These differences were associated with significantly more regressive saccades and longer fixation durations, but not with changes in saccadic amplitudes. CONCLUSIONS. In strabismic amblyopia, reading is impaired, not only during monocular viewing with the amblyopic eye, but also with the nonamblyopic eye and binocularly, even though normal visual acuity pertains to the latter two conditions. The impaired reading performance is associated with differences in both the saccadic and fixational patterns, most likely as adaptation strategies to abnormal sensory experiences such as crowding and suppression.

  5. Bilateral optic nerve head drusen with chorioretinal coloboma in the right eye.

    PubMed

    Dehghani, Ali Reza; Rezaei, Leila; Ghanbari, Heshmatollah

    2016-01-01

    Chorioretinal coloboma is a congenital defect of the eye caused by improper closure of the embryonic fissure. Optic nerve head drusen (ONHD) are white calcareous deposits that are generally asymptomatic. We report a very rare association of both in a healthy patient with no any systemic syndrome. A 16-year-old man was referred to our clinic from suffering blurred vision. Best corrected visual acuity of the right eye was 6/10 and 10/10 in the left one. External ocular and slit lamp examination were normal. Dilated ophthalmoscopy showed marked swelling in both optic nerves and chorioretinal coloboma in the right eye inferiorly. Ultrasonography showed an echodense structure with acoustic shadowing in both eyes consistent with buried ONHD. Visual field testing showed normal field in the left eye and moderate superior field depression in the right eye corresponding to inferior coloboma in funduscopy. Results of general medical and neurologic, cardiologic, and other examinations were normal. To the best our knowledge combination of bilateral ONHD and unilateral chorioretinal coloboma in a healthy patient with no any systemic syndrome has not been published in the literature. We reported this very rare association and recommended examine eyes and other body organs. In such cases that coloboma is associated with ONHD, we should keep in mind Noonan syndrome. The diagnosis of Noonan syndrome is clinical and confirm by the consultant pediatricians and clinical geneticists.

  6. Bilateral optic nerve head drusen with chorioretinal coloboma in the right eye

    PubMed Central

    Dehghani, Ali Reza; Rezaei, Leila; Ghanbari, Heshmatollah

    2016-01-01

    Chorioretinal coloboma is a congenital defect of the eye caused by improper closure of the embryonic fissure. Optic nerve head drusen (ONHD) are white calcareous deposits that are generally asymptomatic. We report a very rare association of both in a healthy patient with no any systemic syndrome. A 16-year-old man was referred to our clinic from suffering blurred vision. Best corrected visual acuity of the right eye was 6/10 and 10/10 in the left one. External ocular and slit lamp examination were normal. Dilated ophthalmoscopy showed marked swelling in both optic nerves and chorioretinal coloboma in the right eye inferiorly. Ultrasonography showed an echodense structure with acoustic shadowing in both eyes consistent with buried ONHD. Visual field testing showed normal field in the left eye and moderate superior field depression in the right eye corresponding to inferior coloboma in funduscopy. Results of general medical and neurologic, cardiologic, and other examinations were normal. To the best our knowledge combination of bilateral ONHD and unilateral chorioretinal coloboma in a healthy patient with no any systemic syndrome has not been published in the literature. We reported this very rare association and recommended examine eyes and other body organs. In such cases that coloboma is associated with ONHD, we should keep in mind Noonan syndrome. The diagnosis of Noonan syndrome is clinical and confirm by the consultant pediatricians and clinical geneticists. PMID:27099847

  7. Echocardiographic Assessment of Cardiac Changes During Normal Pregnancy Among Nigerians

    PubMed Central

    Adeyeye, V. O.; Balogun, M. O.; Adebayo, R. A.; Makinde, O. N.; Akinwusi, P. O.; Ajayi, E. A.; Ogunyemi, S. A.; Akintomide, A. O.; Ajayi, E. O.; Adeyeye, A. G.; Ojo, T. O.; Abiodun, O. O.

    2016-01-01

    BACKGROUND Pregnancy is a physiological process associated with an increased hemodynamic load and cardiac structural remodeling. Limited echocardiographic information exists on cardiac chambers, left ventricular (LV) systolic and diastolic functions, and LV mass during trimesters of normal pregnancy among African women. MATERIALS AND METHODS Echocardiography was done at the beginning of the second trimester, beginning of the third trimester, and middle of the third trimester for 100 normal pregnant women and at one visit for age-matched 100 nonpregnant women. The data were analyzed using the Statistical Package for Social Sciences (SPSS) version 17 software. Analysis of variance was used to compare within trimesters, and a P value of <0.05 was considered significant. RESULTS The mean (SD) ages of the patients and controls were 28.20 (±5.91) and 28.35 (±6.06) years, respectively (age range = 19–44 years, P = 0.86). Cardiac chambers, LV systolic function, and LV mass and its index increased significantly during pregnancy. A significant increase in A-wave velocity but slight increase in E-wave velocity and a reduction in tissue e′ velocity at the septal margin but a progressive increase in a′ velocity were also observed (P < 0.05). CONCLUSION Cardiac chamber dimensions, LV wall thickness, and mass, most indices of LV systolic and diastolic function, though within normal range, were significantly higher in pregnant than in nonpregnant Nigerian women. PMID:27656092

  8. Eye shape illusions induced by eyebrow positions.

    PubMed

    Matsushita, Soyogu; Morikawa, Kazunori; Mitsuzane, Saya; Yamanami, Haruna

    2015-01-01

    We investigated whether the position of the eyebrows influences the perceived shape of the eyes by employing psychophysical measurements. Experiment 1 used arched and straight eyebrows at five different inclinations as stimuli and measured the perceived inclination of the eyes. The results demonstrated that the eyes are perceived to be somewhat inclined in the same direction as the eyebrows. Experiment 2 measured the perceived eye size by manipulating the distance between the eyes and the eyebrows and the curvature of the eyebrows across three levels. The results showed that the lower eyebrows (ie closer to eyes) made the eyes appear larger and the higher eyebrows made the eyes appear smaller, while eyebrow curvature had no effect on perceived eye size. Experiment 3 examined the role of the eye-eyebrow distance in the eye inclination illusion shown in experiment 1. The eye inclination illusion was unaffected by the eye-eyebrow distance, suggesting that the eye inclination illusion and the eye size illusion may involve different kinds of assimilation. These illusions are discussed in terms of face perception and possible practical applications.

  9. Human eye anisoplanatism: eye as a lamellar structure

    NASA Astrophysics Data System (ADS)

    Dubinin, Alexander; Cherezova, Tatyana; Belyakov, Alexey; Kudryashov, Alexis

    2006-02-01

    In this paper we consider anisoplanatism effect as a fundamental limitation on the size of high resolution area (isoplanatic patch) of retinal images obtained using fundus cameras equipped with adaptive optics. Isoplanatic patch size was estimated using experimental results for on-axis and off-axis eye aberrations measured by Shack-Hartmann technique. Isoplanatic patch size varied among examined subjects in the range from 1.5 ° to 2.5 ° which is in good agreement with results obtained using ray-tracing technique1. We estimated isoplanatic patch size for Gullstrand eye model and found it to be close to the values obtained from experimental results for subjects with good vision. We also discuss the possibilities of Gullstrand eye model modifications for modeling anisoplanatism effect for each particular subject. We also estimated the efficiency of multibeacon correction method and found out that this method allows us to almost twice increase the area with high resolution.

  10. Vision, eye disease, and art: 2015 Keeler Lecture

    PubMed Central

    Marmor, M F

    2016-01-01

    The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology. PMID:26563659

  11. Vision, eye disease, and art: 2015 Keeler Lecture.

    PubMed

    Marmor, M F

    2016-02-01

    The purpose of this study was to examine normal vision and eye disease in relation to art. Ophthalmology cannot explain art, but vision is a tool for artists and its normal and abnormal characteristics may influence what an artist can do. The retina codes for contrast, and the impact of this is evident throughout art history from Asian brush painting, to Renaissance chiaroscuro, to Op Art. Art exists, and can portray day or night, only because of the way retina adjusts to light. Color processing is complex, but artists have exploited it to create shimmer (Seurat, Op Art), or to disconnect color from form (fauvists, expressionists, Andy Warhol). It is hazardous to diagnose eye disease from an artist's work, because artists have license to create as they wish. El Greco was not astigmatic; Monet was not myopic; Turner did not have cataracts. But when eye disease is documented, the effects can be analyzed. Color-blind artists limit their palette to ambers and blues, and avoid greens. Dense brown cataracts destroy color distinctions, and Monet's late canvases (before surgery) showed strange and intense uses of color. Degas had failing vision for 40 years, and his pastels grew coarser and coarser. He may have continued working because his blurred vision smoothed over the rough work. This paper can barely touch upon the complexity of either vision or art. However, it demonstrates some ways in which understanding vision and eye disease give insight into art, and thereby an appreciation of both art and ophthalmology.

  12. The vortex formation time to diastolic function relation: assessment of pseudonormalized versus normal filling

    PubMed Central

    Ghosh, Erina; Kovács, Sándor J

    2013-01-01

    In early diastole, the suction pump feature of the left ventricle opens the mitral valve and aspirates atrial blood. The ventricle fills via a blunt profiled cylindrical jet of blood that forms an asymmetric toroidal vortex ring inside the ventricle whose growth has been quantified by the standard (dimensionless) expression for vortex formation time, VFTstandard = {transmitral velocity time integral}/{mitral orifice diameter}. It can differentiate between hearts having distinguishable early transmitral (Doppler E-wave) filling patterns. An alternative validated expression, VFTkinematic reexpresses VFTstandard by incorporating left heart, near “constant-volume pump” physiology thereby revealing VFTkinematic's explicit dependence on maximum rate of longitudinal chamber expansion (E′). In this work, we show that VFTkinematic can differentiate between hearts having indistinguishable E-wave patterns, such as pseudonormal (PN; 0.75 < E/A < 1.5 and E/E′ > 8) versus normal. Thirteen age-matched normal and 12 PN data sets (738 total cardiac cycles), all having normal LVEF, were selected from our Cardiovascular Biophysics Laboratory database. Doppler E-, lateral annular E′-waves, and M-mode data (mitral leaflet separation, chamber dimension) was used to compute VFTstandard and VFTkinematic. VFTstandard did not differentiate between groups (normal [3.58 ± 1.06] vs. PN [4.18 ± 0.79], P = 0.13). In comparison, VFTkinematic for normal (3.15 ± 1.28) versus PN (4.75 ± 1.35) yielded P = 0.006. Hence, the applicability of VFTkinematic for diastolic function quantitation has been broadened to include analysis of PN filling patterns in age-matched groups. PMID:24400169

  13. The role of corneal innervation in LASIK-induced neuropathic dry eye.

    PubMed

    Chao, Cecilia; Golebiowski, Blanka; Stapleton, Fiona

    2014-01-01

    Almost half the patients who undergo laser in situ keratomileusis (LASIK) experience dry eye following the procedure. However, the etiology of LASIK-induced dry eye is unclear. The purpose of this review is to examine and summarize the current evidence for the etiology of LASIK-induced dry eye, with a focus on ocular surface sensitivity and corneal innervation. Evidence suggests that the alteration of corneal nerves after LASIK is the most likely cause of the subjective symptoms of LASIK-induced dry eye, even though corneal sensitivity and the clinical indicators of dry eye return to apparently normal values within a year due to the partial recovery of the corneal nerve plexus. The hypothesis is explored that dry eye symptoms following LASIK may result from abnormal sensation due to LASIK-induced corneal neuropathy. Other factors, such as alterations in conjunctival goblet cell density, might also contribute to the symptoms and signs of LASIK-induced dry eye. Inter-relationships between nerve morphology, tear neuropeptide levels and dry eye require further investigation. A better understanding of this phenomenon may result in improved management of post-LASIK dry eye.

  14. Clinical significance of a new autoantibody against a human eye muscle soluble antigen, detected by immunofluorescence.

    PubMed Central

    Mengistu, M; Laryea, E; Miller, A; Wall, J R

    1986-01-01

    The clinical significance of a circulating autoantibody against a recently identified soluble human eye muscle-derived antigen was studied in patients with Graves' ophthalmopathy and autoimmune thyroid disorders. Tests were positive in 73% of patients with Graves' ophthalmopathy, including six of seven with no associated thyroid disease (euthyroid Graves' disease). Tests were also positive in 27% of patients with hyperthyroidism but no clinically apparent eye disease, in 13% of patients with Hashimoto's thyroiditis without eye disease, in two of 12 patients with subacute thyroiditis, in one of 20 patients with nonimmunological thyroid disorders but in none of 39 normal subjects. There were significant positive correlations between serum levels of the antibody (expressed as a titre) and the severity of the eye muscle component quantified as an index as well as the duration of the eye disease. Antibodies were detected in three of five patients with only lid lag and state who subsequently developed active ophthalmopathy, in six of nine patients who developed eye disease after treatment of their hyperthyroidism and in one of eight first degree relatives of patients with Graves' ophthalmopathy. In addition three of the 12 patients with autoimmune thyroid disease without apparent eye involvement, but positive antibody tests, have developed ophthalmopathy since the time of testing. These findings suggest that tests for antibodies against a soluble human eye muscle antigen may be useful clinically as a diagnostic test and to predict the onset of eye disease in predisposed patients and subjects. PMID:3539423

  15. Comparison of smooth pursuit and combined eye-head tracking in human subjects with deficient labyrinthine function

    NASA Technical Reports Server (NTRS)

    Leigh, R. J.; Thurston, S. E.; Sharpe, J. A.; Ranalli, P. J.; Hamid, M. A.

    1987-01-01

    The effects of deficient labyrinthine function on smooth visual tracking with the eyes and head were investigated, using ten patients with bilateral peripheral vestibular disease and ten normal controls. Active, combined eye-head tracking (EHT) was significantly better in patients than smooth pursuit with the eyes alone, whereas normal subjects pursued equally well in both cases. Compensatory eye movements during active head rotation in darkness were always less in patients than in normal subjects. These data were used to examine current hypotheses that postulate central cancellation of the vestibulo-ocular reflex (VOR) during EHT. A model that proposes summation of an integral smooth pursuit command and VOR/compensatory eye movements is consistent with the findings. Observation of passive EHT (visual fixation of a head-fixed target during en bloc rotation) appears to indicate that in this mode parametric gain changes contribute to modulation of the VOR.

  16. 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

  17. Best practice eye care models.

    PubMed

    Qureshi, Babar M; Mansur, Rabiu; Al-Rajhi, Abdulaziz; Lansingh, Van; Eckert, Kristen; Hassan, Kunle; Ravilla, Thulasiraj; Muhit, Mohammad; Khanna, Rohit C; Ismat, Chaudhry

    2012-01-01

    Since the launching of Global Initiative, VISION 2020 "the Right to Sight" many innovative, practical and unique comprehensive eye care services provision models have evolved targeting the underserved populations in different parts of the World. At places the rapid assessment of the burden of eye diseases in confined areas or utilizing the key informants for identification of eye diseases in the communities are promoted for better planning and evidence based advocacy for getting / allocation of resources for eye care. Similarly for detection and management of diabetes related blindness, retinopathy of prematurity and avoidable blindness at primary level, the major obstacles are confronted in reaching to them in a cost effective manner and then management of the identified patients accordingly. In this regard, the concept of tele-ophthalmology model sounds to be the best solution. Whereas other models on comprehensive eye care services provision have been emphasizing on surgical output through innovative scales of economy that generate income for the program and ensure its sustainability, while guaranteeing treatment of the poorest of the poor.

  18. Eye formation in rotating convection

    NASA Astrophysics Data System (ADS)

    Oruba, L.; Davidson, P. A.; Dormy, E.

    2017-02-01

    We consider rotating convection in a shallow, cylindrical domain. We examine the conditions under which the resulting vortex develops an eye at its core; that is, a region where the poloidal flow reverses and the angular momentum is low. For simplicity, we restrict ourselves to steady, axisymmetric flows in a Boussinesq fluid. Our numerical experiments show that, in such systems, an eye forms as a passive response to the development of a so-called eyewall, a conical annulus of intense, negative azimuthal vorticity that can form near the axis and separates the eye from the primary vortex. We also observe that the vorticity in the eyewall comes from the lower boundary layer, and relies on the fact the poloidal flow strips negative vorticity out of the boundary layer and carries it up into the fluid above as it turns upward near the axis. This process is effective only if the Reynolds number is sufficiently high for the advection of vorticity to dominate over diffusion. Finally we observe that, in the vicinity of the eye and the eyewall, the buoyancy and Coriolis forces are negligible, and so although these forces are crucial to driving and shaping the primary vortex, they play no direct role in eye formation in a Boussinesq fluid.

  19. How flies clean their eyes

    NASA Astrophysics Data System (ADS)

    Amador, Guillermo; Durand, Fabien; Mao, Wenbin; Alexeev, Alexander; Hu, David

    2013-11-01

    Flying insects face a barrage of foreign particles such as dust and pollen, which threaten to coat the insect's eyes and antennae, limiting their sensing abilities. In this study, we elucidate novel aerodynamic and elastic mechanisms by which insects keep these organs clean. The compound eye of many species of insects is covered by an array of short bristles, or setae, evenly spaced between each photoreceptor unit. Among these insect species, setae length is triple their spacing. We conduct numerical simulations and wind tunnel experiments using an insect eye mimic to show this critical setae length reduces shear rate at the eye surface by 80%. Thus, the setae create a stagnant zone in front of the eye, which diverts airflow to reduce deposition of particles. Setae can also act as springboards to catapult accumulated particles. In high speed videography of insects using their legs to clean themselves, we observe deflected setae hurling micron scale particles at accelerations over 100 times earth's gravity. The dual abilities of setae to divert airflow and catapult particles may motivate bio-inspired designs for dust-controlling lenses, sensors, and solar panels.

  20. Best practice eye care models

    PubMed Central

    Qureshi, Babar M; Mansur, Rabiu; Al-Rajhi, Abdulaziz; Lansingh, Van; Eckert, Kristen; Hassan, Kunle; Ravilla, Thulasiraj; Muhit, Mohammad; Khanna, Rohit C; Ismat, Chaudhry

    2012-01-01

    Since the launching of Global Initiative, VISION 2020 “the Right to Sight” many innovative, practical and unique comprehensive eye care services provision models have evolved targeting the underserved populations in different parts of the World. At places the rapid assessment of the burden of eye diseases in confined areas or utilizing the key informants for identification of eye diseases in the communities are promoted for better planning and evidence based advocacy for getting / allocation of resources for eye care. Similarly for detection and management of diabetes related blindness, retinopathy of prematurity and avoidable blindness at primary level, the major obstacles are confronted in reaching to them in a cost effective manner and then management of the identified patients accordingly. In this regard, the concept of tele-ophthalmology model sounds to be the best solution. Whereas other models on comprehensive eye care services provision have been emphasizing on surgical output through innovative scales of economy that generate income for the program and ensure its sustainability, while guaranteeing treatment of the poorest of the poor. PMID:22944741

  1. The anabolic activity of bone tissue, suppressed by disuse, is normalized by brief exposure to extremely low-magnitude mechanical stimuli

    NASA Technical Reports Server (NTRS)

    Rubin, C.; Xu, G.; Judex, S.

    2001-01-01

    It is generally believed that mechanical signals must be large in order to be anabolic to bone tissue. Recent evidence indicates, however, that extremely low-magnitude (<10 microstrain) mechanical signals readily stimulate bone formation if induced at a high frequency. We examined the ability of extremely low-magnitude, high-frequency mechanical signals to restore anabolic bone cell activity inhibited by disuse. Adult female rats were randomly assigned to six groups: baseline control, age-matched control, mechanically stimulated for 10 min/day, disuse (hind limb suspension), disuse interrupted by 10 min/day of weight bearing, and disuse interrupted by 10 min/day of mechanical stimulation. After a 28 day protocol, bone formation rates (BFR) in the proximal tibia of mechanically stimulated rats increased compared with age-matched control (+97%). Disuse alone reduced BFR (-92%), a suppression only slightly curbed when disuse was interrupted by 10 min of weight bearing (-61%). In contrast, disuse interrupted by 10 min per day of low-level mechanical intervention normalized BFR to values seen in age-matched controls. This work indicates that this noninvasive, extremely low-level stimulus may provide an effective biomechanical intervention for the bone loss that plagues long-term space flight, bed rest, or immobilization caused by paralysis.

  2. Corneal Transplantation in Disease Affecting Only One Eye: Does It Make a Difference to Habitual Binocular Viewing?

    PubMed Central

    Bandela, Praveen K.; Satgunam, PremNandhini; Garg, Prashant; Bharadwaj, Shrikant R.

    2016-01-01

    Background Clarity of the transplanted tissue and restoration of visual acuity are the two primary metrics for evaluating the success of corneal transplantation. Participation of the transplanted eye in habitual binocular viewing is seldom evaluated post-operatively. In unilateral corneal disease, the transplanted eye may remain functionally inactive during binocular viewing due to its suboptimal visual acuity and poor image quality, vis-à-vis the healthy fellow eye. Methods and Findings This study prospectively quantified the contribution of the transplanted eye towards habitual binocular viewing in 25 cases with unilateral transplants [40yrs (IQR: 32–42yrs) and 25 age-matched controls [30yrs (25–37yrs)]. Binocular functions including visual field extent, high-contrast logMAR acuity, suppression threshold and stereoacuity were assessed using standard psychophysical paradigms. Optical quality of all eyes was determined from wavefront aberrometry measurements. Binocular visual field expanded by a median 21% (IQR: 18–29%) compared to the monocular field of cases and controls (p = 0.63). Binocular logMAR acuity [0.0 (0.0–0.0)] almost always followed the fellow eye’s acuity [0.00 (0.00 –-0.02)] (r = 0.82), independent of the transplanted eye’s acuity [0.34 (0.2–0.5)] (r = 0.04). Suppression threshold and stereoacuity were poorer in cases [30.1% (13.5–44.3%); 620.8arc sec (370.3–988.2arc sec)] than in controls [79% (63.5–100%); 16.3arc sec (10.6–25.5arc sec)] (p<0.001). Higher-order wavefront aberrations of the transplanted eye [0.34μ (0.21–0.51μ)] were higher than the fellow eye [0.07μ (0.05–0.11μ)] (p<0.001) and their reduction with RGP contact lenses [0.09μ (0.08–0.12μ)] significantly improved the suppression threshold [65% (50–72%)] and stereoacuity [56.6arc sec (47.7–181.6arc sec)] (p<0.001). Conclusions In unilateral corneal disease, the transplanted eye does participate in gross binocular viewing but offers limited support

  3. An artificial compound eye for stereoendoscopy.

    PubMed

    Szema, R; Rastegar, J; Lee, L

    2004-01-01

    A scanning endoscope has been designed with the ability to both project three-dimensional images and provide precise measurements of internal structures. This is beneficial for minimally invasive surgery, where surgeons suffer from a lack of depth perception, limited field of view, and the absence of a reference frame for dimensional measurements. Borrowing from the insect compound eye, the design uses an array of prisms, each facing a different direction but with overlapping fields of view. The prisms redirect their respective images normal to a fibre optic imaging plane and are individually controlled by electro-chromic shutters. The device thereby retains the ability to scan in multiple directions without mechanical parts and uses only a single camera. Comparison of the overlapping images with known prism positions allows for the calculation of absolute coordinates. Results from large-scale models show that the technology is plausible, and fabrication methods for a smaller device are discussed.

  4. Choosing Wisely When It Comes to Eye Care: Antibiotics for Eye Injections

    MedlinePlus

    ... Stories Español Eye Health / News Choosing Wisely When It Comes to Eye Care, Part 4 Jun. 10, ... good vision and losing your eyesight. Sometimes, though, it is difficult to know how much eye care ...

  5. Choosing Wisely When It Comes to Eye Care: Punctal Plugs for Dry Eye

    MedlinePlus

    ... Stories Español Eye Health / News Choosing Wisely When It Comes to Eye Care, Part 5 Mar. 19, ... good vision and losing your eyesight. Sometimes, though, it is difficult to know how much eye care ...

  6. Eye-Eye with Dr. Rachel Bishop | NIH MedlinePlus the Magazine

    MedlinePlus

    ... this page please turn JavaScript on. Feature: Glaucoma Eye-to-Eye with Dr. Rachel Bishop Past Issues / Spring 2015 ... new patient comes in because they scratched their eye while working in the yard, or they think ...

  7. Videos from the National Eye Institute: Eye Diseases | NIH MedlinePlus the Magazine

    MedlinePlus

    ... Javascript on. Feature: Vision Videos from the National Eye Institute: Eye Diseases Past Issues / Winter 2012 Table of Contents ... Rachel Bishop, NEI’s Chief of Consult Services, discusses eye health and the importance of comprehensive dilated exams ...

  8. 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

  9. Tracking with the mind's eye

    NASA Technical Reports Server (NTRS)

    Krauzlis, R. J.; Stone, L. S.

    1999-01-01

    The two components of voluntary tracking eye-movements in primates, pursuit and saccades, are generally viewed as relatively independent oculomotor subsystems that move the eyes in different ways using independent visual information. Although saccades have long been known to be guided by visual processes related to perception and cognition, only recently have psychophysical and physiological studies provided compelling evidence that pursuit is also guided by such higher-order visual processes, rather than by the raw retinal stimulus. Pursuit and saccades also do not appear to be entirely independent anatomical systems, but involve overlapping neural mechanisms that might be important for coordinating these two types of eye movement during the tracking of a selected visual object. Given that the recovery of objects from real-world images is inherently ambiguous, guiding both pursuit and saccades with perception could represent an explicit strategy for ensuring that these two motor actions are driven by a single visual interpretation.

  10. Eye abnormalities in Fryns syndrome.

    PubMed

    Pierson, Diane M; Taboada, Eugenio; Butler, Merlin G

    2004-03-15

    Fryns syndrome is a rare, generally lethal, autosomal recessive multiple congenital anomaly (MCA) syndrome first described in 1979. Patients with the syndrome present with the classical findings of cloudy cornea, brain malformations, diaphragmatic defects, and distal limb deformities. Over 70 patients have been reported revealing a wide variety of phenotypic features. Although initially considered a major feature of Fryns syndrome, cloudy cornea has been relegated as a minor diagnostic sign and not commonly reported in patients since the original description. However, eye findings per se are not uncommon. Abnormal eye findings occasionally reported in Fryns syndrome potentially result in amblyopia and blindness, profoundly affecting neurologic outcome of those who survive the neonatal period. We reviewed 77 reported patients with Fryns syndrome and summarized the abnormal eye findings identified in 12 of the reported cases. In addition, we contribute three new patients with Fryns syndrome, one of which demonstrated unilateral microphthalmia and cloudy cornea.

  11. Moving Ahead With Eye Power

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA's Jet Propulsion Laboratory's collaborated with LC Technologies, Inc., to improve LCT's Eyegaze Communication System, an eye tracker that enables people with severe cerebral palsy, muscular dystrophy, multiple sclerosis, strokes, brain injuries, spinal cord injuries, and ALS (amyotrophic lateral sclerosis) to communicate and control their environment using their eye movements. To operate the system, the user sits in front of the computer monitor while the camera focuses on one eye. By looking at control keys on the monitor for a fraction of a second, the user can 'talk' with speech synthesis, type, operate a telephone, access the Internet and e-mail, and run computer software. Nothing is attached to the user's head or body, and the improved size and portability allow the system to be mounted on a wheelchair. LCT and JPL are working on several other areas of improvement that have commercial add-on potential.

  12. The period of susceptibility to the physiological effects of unilateral eye closure in kittens.

    PubMed

    Hubel, D H; Wiesel, T N

    1970-02-01

    1. Kittens were visually deprived by suturing the lids of the right eye for various periods of time at different ages. Recordings were subsequently made from the striate cortex, and responses from the two eyes compared. As previously reported, monocular eye closure during the first few months of life causes a sharp decline in the number of cells that can be influenced by the previously closed eye.2. Susceptibility to the effects of eye closure begins suddenly near the start of the fourth week, remains high until some time between the sixth and eighth weeks, and then declines, disappearing finally around the end of the third month. Monocular closure for over a year in an adult cat produces no detectable effects.3. During the period of high susceptibility in the fourth and fifth weeks eye closure for as little as 3-4 days leads to a sharp decline in the number of cells that can be driven from both eyes, as well as an over-all decline in the relative influence of the previously closed eye. A 6-day closure is enough to give a reduction in the number of cells that can be driven by the closed eye to a fraction of the normal. The physiological picture is similar to that following a 3-month monocular deprivation from birth, in which the proportion of cells the eye can influence drops from 85 to about 7%.4. Cells of the lateral geniculate receiving input from a deprived eye are noticeably smaller and paler to Nissl stain following 3 or 6 days' deprivation during the fourth week.5. Following 3 months of monocular deprivation, opening the eye for up to 5 yr produces only a very limited recovery in the cortical physiology, and no obvious recovery of the geniculate atrophy, even though behaviourally there is some return of vision in the deprived eye. Closing the normal eye, though necessary for behavioural recovery, has no detectable effect on the cortical physiology. The amount of possible recovery in the striate cortex is probably no greater if the period of eye closure is

  13. Ivermectin for onchocercal eye disease (river blindness)

    PubMed Central

    Ejere, Henry OD; Schwartz, Ellen; Wormald, Richard; Evans, Jennifer R

    2015-01-01

    Background It is believed that ivermectin (a microfilaricide) could prevent blindness due to onchocerciasis. However, when given to everyone in communities where onchocerciasis is common, the effects of ivermectin on lesions affecting the eye are uncertain and data on whether the drug prevents visual loss are unclear. Objectives The aim of this review was to assess the effectiveness of ivermectin in preventing visual impairment and visual field loss in onchocercal eye disease. The secondary aim was to assess the effects of ivermectin on lesions affecting the eye in onchocerciasis. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 3), MEDLINE (January 1950 to April 2012), EMBASE (January 1980 to April 2012), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrials.gov) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 2 April 2012. Selection criteria We included randomised controlled trials with at least one year of follow-up comparing ivermectin with placebo or no treatment. Participants in the trials were people normally resident in endemic onchocercal communities with or without one or more characteristic signs of ocular onchocerciasis. Data collection and analysis Two review authors independently extracted data and assessed trial quality. We contacted study authors for additional information. As trials varied in design and setting, we were unable to perform a meta-analysis. Main results The review included four trials: two small studies (n = 398) in which people with onchocercal infection were given one dose of ivermectin or placebo and followed up for one year; and two larger community-based studies (n = 4941) whereby all individuals in

  14. Eye trackers in an oculary clinical setting

    NASA Astrophysics Data System (ADS)

    Shahimin, Mizhanim M.; Shahimin, Mukhzeer M.

    2013-12-01

    Infrared eye tracker has been demonstrated to provide a more objective and quantitative results of the cover test measurement in eye care practices. This paper reviews the application of eye trackers in oculary clinical setting. It highlights the different types of eye movement recording system (EMRS) available, the advantages and disadvantages of each and their use in a clinical setting. This paper also discusses the parameters that can be derived from the EMRS and the significance of the parameters in a clinical interpretation. Using an eye tracker would make available to the clinician a simple system for making quantitative measurements when performing the cover test in an eye examination.

  15. Xenon contrast CT-CBF measurements in parkinsonism and normal aging.

    PubMed

    Tachibana, H; Meyer, J S; Kitagawa, Y; Tanahashi, N; Kandula, P; Rogers, R L

    1985-06-01

    Local cerebral blood flow (LCBF) and local tissue:blood partition, coefficient (L lambda) values were measured during CT scanning while patients with different types of Parkinson's syndrome (N = 14) inhaled a contrast mixture of 35-37 per cent stable xenon gas in oxygen. Single-compartment analysis fitted to infinity was used to calculate L lambda and LCBF values. Results were compared with results from normal age-matched volunteers (N = 24). Mean hemispheric (p less than 0.05) and subcortical (p less than 0.05) gray matter LCBF values were reduced in idiopathic Parkinson's disease (N = 11), compared to values from age-matched normals. Regionally, LCBF reductions included frontal (p less than 0.001), parietal cortex (p less than 0.05), caudate (p less than 0.05), lentiform nuclei (p less than 0.001) and thalamus (p less than 0.05) reductions. L lambda values were normal. Unilateral tremor and/or rigidity correlated directly with reduced LCBF in contralateral lentiform (p less than 0.01) and caudate (p less than 0.01) nuclei. In postencephalitic Parkinsonism (N = 1) LCBF reductions were diffuse, with normal L lambda values. In the akinetic form of Parkinsonism (N = 1) associated with lacunar infarcts, LCBF and L lambda reductions were patchy. In Parkinsonism following carbon monoxide poisoning (N = 1), LCBF values of gray and white matter were diffusely reduced and L lambda values were reduced in both pallidal regions. When dementia was present together with Parkinsonism (N = 3), LCBF reductions were more diffuse and severe. Dopaminergic deficiency correlated directly with reduced LCBF values, reflecting the severity of Parkinsonism.

  16. The contralateral foot in children with unilateral clubfoot, is the unaffected side normal?

    PubMed

    Cooper, Anthony; Chhina, Harpreet; Howren, Alyssa; Alvarez, Christine

    2014-07-01

    The unilateral unaffected clubfoot has previously been used as a control in longitudinal studies of clubfoot outcomes. However, we have observed that the unaffected clubfoot does not necessarily exhibit the same pedobarographic measurements as seen in normal control subjects. The purpose of this study was to evaluate whether the unaffected foot is indeed normal or if there are differences in the pedobarographic measurements of the unaffected foot compared to healthy normal controls.The Tekscan HR Mat™ was used to dynamically test the walking pattern of 103 subjects with unilateral clubfeet and compare the results to our previously published series of normal controls. Patients were divided into three groups: Group 1 (< 2 years), Group 2 (2-5 years) and Group 3 (>5 years). An unpaired t-test (p < 0.05) was used to compare percentage of stance at initiation of force, the percentage of stance at maximum force, the percentage of stance at termination of force, the maximum percentage force and the average force/time integral between a group of normal age matched controls and the unaffected foot in patients with unilateral clubfoot. Significant differences were identified between the unaffected side and normal controls for the pressure distribution, order of initial contact and foot contact time. These differences evolved and changed with age. The pedobarographic measurements of patients with clubfoot are not normal for the unaffected foot. As such the unaffected foot should not be referred to as normal, nor should it be used as a control.

  17. The development of eye shape and the origin of lower field myopia in the guinea pig eye.

    PubMed

    Zeng, Guang; Bowrey, Hannah E; Fang, Jun; Qi, Yanhua; McFadden, Sally A

    2013-01-14

    In a variety of species, the refractive state of the eye differs in different parts of the visual field (VF) with greater myopia in the region that views the ground ("lower field myopia"). We studied the refraction and eye shape of the normal guinea pig eye to determine what feature(s) underlie this visual adaptation. Guinea pigs (n=67) were either newborn or raised under incandescent light until 14, 37 or 45 days of age (20, 44, 20 and 11 eyes respectively). Refractive error was measured on-axis and 30° off-axis in the superior (SVF), inferior (IVF), temporal (TVF) and nasal (NVF) visual fields. Eye shape was analyzed from images of frozen hemisections in both the horizontal and vertical mid plane in 14 day animals, and in the vertical plane at 0, 14 and 45 days of age. Axial distances in vitro were correlated with in vivo high frequency ultrasound (r(2)=0.90). In the horizontal plane, asymmetry was caused by a ± 6° conical zone surrounding the optic nerve (12° off-axis in NVF), suggesting significant myopia in this zone. At 30°, there was no asymmetry in eye length, but the NVF was +1.7D more myopic due to asymmetry in corneal power. In the vertical plane at 30°, the IVF was more myopic than the SVF by -3.8D at 0 days, -5.9D at 14 days and -6.0D at 37 days. It resulted from vertical asymmetry in the distance of the retina from the lens center, which was longest in the mid IVF. This non-linear ramp retina was present at birth. In older animals, the peak of the ramp shifted more centrally, and the eye developed longer lengths in the extreme upper periphery (SVF) which may have been caused by the low position of the room ceiling. The vertical asymmetry in eye shape was mirrored by changes in choroid thickness, suggesting a mechanism by which eye shape was refined by vision during development. In early life, ocular growth in the vertical plane was 1.7 times higher in the center relative to the periphery, a pattern that reversed in the following month. Since

  18. Does the 'P300' speller depend on eye gaze?

    NASA Astrophysics Data System (ADS)

    Brunner, P.; Joshi, S.; Briskin, S.; Wolpaw, J. R.; Bischof, H.; Schalk, G.

    2010-10-01

    Many people affected by debilitating neuromuscular disorders such as amyotrophic lateral sclerosis, brainstem stroke or spinal cord injury are impaired in their ability to, or are even unable to, communicate. A brain-computer interface (BCI) uses brain signals, rather than muscles, to re-establish communication with the outside world. One particular BCI approach is the so-called 'P300 matrix speller' that was first described by Farwell and Donchin (1988 Electroencephalogr. Clin. Neurophysiol. 70 510-23). It has been widely assumed that this method does not depend on the ability to focus on the desired character, because it was thought that it relies primarily on the P300-evoked potential and minimally, if at all, on other EEG features such as the visual-evoked potential (VEP). This issue is highly relevant for the clinical application of this BCI method, because eye movements may be impaired or lost in the relevant user population. This study investigated the extent to which the performance in a 'P300' speller BCI depends on eye gaze. We evaluated the performance of 17 healthy subjects using a 'P300' matrix speller under two conditions. Under one condition ('letter'), the subjects focused their eye gaze on the intended letter, while under the second condition ('center'), the subjects focused their eye gaze on a fixation cross that was located in the center of the matrix. The results show that the performance of the 'P300' matrix speller in normal subjects depends in considerable measure on gaze direction. They thereby disprove a widespread assumption in BCI research, and suggest that this BCI might function more effectively for people who retain some eye-movement control. The applicability of these findings to people with severe neuromuscular disabilities (particularly in eye-movements) remains to be determined.

  19. Visual Acuity and the Eye.

    ERIC Educational Resources Information Center

    Beynon, J.

    1985-01-01

    Shows that visual acuity is a function of the structure of the eye and that its limit is set by the structure of the retina, emphasizing the role of lens aberrations and difraction on image quality. Also compares human vision with that of other vertebrates and insects. (JN)

  20. Arthropods affecting the human eye.

    PubMed

    Panadero-Fontán, Rosario; Otranto, Domenico

    2015-02-28

    Ocular infestations by arthropods consist in the parasitization of the human eye, either directly (e.g., some insect larvae causing ophthalmomyiasis) or via arthropods feeding on lachrymal/conjunctival secretions (e.g., some eye-seeking insects, which also act as vectors of eye pathogens). In addition, demodicosis and phthiriasis may also cause eye discomfort in humans. Ophthalmomyiasis by larvae of the families Oestridae, Calliphoridae and Sarcophagidae, are frequent causative agents of human ocular infestations. Over the last decades, the extensive use of macrocyclic lactones in cattle has reduced the frequency of infestations by Hypoderma bovis and Hypoderma lineatum (family Oestridae), and consequently, human infestations by these species. A prompt diagnosis of ocular myiasis (e.g., by serological tests) is pivotal for positive prognoses, particularly when the larvae are not detectable during the ophthalmologic examination. Molecular diagnoses may also assist physicians and parasitologists in achieving time-efficient diagnoses of infestations by Oestridae causing myiasis. Finally, due to widespread international travel to exotic destinations, cases of myiasis are increasing in non-endemic areas, therefore requiring physicians to acquire a profound knowledge of the clinical symptoms linked to these infestations to prevent costly, inappropriate treatments or severe complications.