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Sample records for volitional ocular motor

  1. Cerebellum and Ocular Motor Control

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    Amir eKheradmand

    2011-09-01

    Full Text Available An intact cerebellum is a prerequisite for optimal ocular motor performance. The cerebellum fine-tunes each of the subtypes of eye movements so they work together to bring and maintain images of objects of interest on the fovea. Here we review the major aspects of the contribution of the cerebellum to ocular motor control. The approach will be based on structural-functional correlation, combining the effects of lesions and the results from physiologic studies, with the emphasis on the cerebellar regions known to be most closely related to ocular motor function: 1 the flocculus/paraflocculus for high-frequency (brief vestibular responses, sustained pursuit eye movements and gaze-holding, 2 the nodulus/ventral uvula for low-frequency (sustained vestibular responses, and 3 the dorsal oculomotor vermis and its target in the posterior portion of the fastigial nucleus (the fastigial oculomotor region for saccades and pursuit initiation.

  2. Imaging the ocular motor nerves.

    NARCIS (Netherlands)

    Ferreira, T.; Verbist, B.M.; Buchem, M. van; Osch, T. van; Webb, A.

    2010-01-01

    The ocular motor nerves (OMNs) comprise the oculomotor, trochlear and the abducens nerves. According to their course, they are divided into four or five anatomic segments: intra-axial, cisternal, cavernous and intra-orbital and, for the abducens nerve, an additional interdural segment. Magnetic

  3. Volitional control of anticipatory ocular pursuit responses under stabilised image conditions in humans.

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    Barnes, G; Goodbody, S; Collins, S

    1995-01-01

    Ocular pursuit responses have been examined in humans in three experiments in which the pursuit target image has been fully or partially stabilised on the fovea by feeding a recorded eye movement signal back to drive the target motion. The objective was to establish whether subjects could volitionally control smooth eye movement to reproduce trajectories of target motion in the absence of a concurrent target motion stimulus. In experiment 1 subjects were presented with a target moving with a triangular waveform in the horizontal axis with a frequency of 0.325 Hz and velocities of +/- 10-50 degrees/s. The target was illuminated twice per cycle for pulse durations (PD) of 160-640 ms as it passed through the centre position; otherwise subjects were in darkness. Subjects initially tracked the target motion in a conventional closed-loop mode for four cycles. Prior to the next target presentation the target image was stabilised on the fovea, so that any target motion generated resulted solely from volitional eye movement. Subjects continued to make anticipatory smooth eye movements both to the left and the right with a velocity trajectory similar to that observed in the closed-loop phase. Peak velocity in the stabilised-image mode was highly correlated with that in the prior closed-loop phase, but was slightly less (84% on average). In experiment 2 subjects were presented with a continuously illuminated target that was oscillated sinusoidally at frequencies of 0.2-1.34 Hz and amplitudes of +/- 5-20 degrees. After four cycles of closed-loop stimulation the image was stabilised on the fovea at the time of peak target displacement. Subjects continued to generate an oscillatory smooth eye velocity pattern that mimicked the sinusoidal motion of the previous closed-loop phase for at least three further cycles. The peak eye velocity generated ranged from 57-95% of that in the closed-loop phase at frequencies up to 0.8 Hz but decreased significantly at 1.34 Hz. In experiment 3

  4. Infantile-onset saccade initiation delay (congenital ocular motor apraxia).

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    Salman, Michael S

    2015-05-01

    Infantile-onset saccade initiation delay, also known as congenital ocular motor apraxia, typically presents in early infancy with horizontal head thrusts once head control is achieved. Defective initiation of horizontal saccades and saccade hypometria with normal saccadic velocity are characteristic findings. Isolated impairment of vertical saccades is rare. Impaired smooth ocular pursuit may be seen. Other relatively common features include developmental delay, hypotonia, ataxia, or clumsiness. Brain MRI may be normal or show a diverse range of abnormalities, most commonly involving the cerebellum. Defective slow phases of the optokinetic response are commonly associated with brain MRI abnormalities. Isolated defect of vertical saccade initiation may indicate supratentorial brain abnormalities on MRI. Joubert syndrome, a developmental midbrain-hindbrain malformation, and ataxia telangiectasia are both commonly associated with defective volitional and reflexive saccade initiation, saccade hypometria, and head thrusts. Both horizontal and vertical saccades are impaired in these two disorders.

  5. White matter microstructure and volitional motor activity in schizophrenia: A diffusion kurtosis imaging study.

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    Docx, Lise; Emsell, Louise; Van Hecke, Wim; De Bondt, Timo; Parizel, Paul M; Sabbe, Bernard; Morrens, Manuel

    2017-02-28

    Avolition is a core feature of schizophrenia and may arise from altered brain connectivity. Here we used diffusion kurtosis imaging (DKI) to investigate the association between white matter (WM) microstructure and volitional motor activity. Multi-shell diffusion MRI and 24-h actigraphy data were obtained from 20 right-handed patients with schizophrenia and 16 right-handed age and gender matched healthy controls. We examined correlations between fractional anisotropy (FA), mean diffusivity (MD), mean kurtosis (MK), and motor activity level, as well as group differences in these measures. In the patient group, increasing motor activity level was positively correlated with MK in the inferior, medial and superior longitudinal fasciculus, the corpus callosum, the posterior fronto-occipital fasciculus and the posterior cingulum. This association was not found in control subjects or in DTI measures. These results show that a lack of volitional motor activity in schizophrenia is associated with potentially altered WM microstructure in posterior brain regions associated with cognitive function and motivation. This could reflect both illness related dysconnectivity which through altered cognition, manifests as reduced volitional motor activity, and/or the effects of reduced physical activity on brain WM. Copyright © 2016. Published by Elsevier B.V.

  6. Imaging the ocular motor nerves

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    Ferreira, Teresa [Department of Radiology, Leiden University Medical Center (Netherlands)], E-mail: T.A.Ferreira@lumc.nl; Verbist, Berit [Department of Radiology, Leiden University Medical Center (Netherlands)], E-mail: B.M.Verbist@lumc.nl; Buchem, Mark van [Department of Radiology, Leiden University Medical Center (Netherlands)], E-mail: M.A.van_Buchem@lumc.nl; Osch, Thijs van [C.J. Gorter for High-Field MRI, Department of Radiology, Leiden University Medical Center (Netherlands)], E-mail: M.J.P.van_Osch@lumc.nl; Webb, Andrew [C.J. Gorter for High-Field MRI, Department of Radiology, Leiden University Medical Center (Netherlands)], E-mail: A.Webb@lumc.nl

    2010-05-15

    The ocular motor nerves (OMNs) comprise the oculomotor, trochlear and the abducens nerves. According to their course, they are divided into four or five anatomic segments: intra-axial, cisternal, cavernous and intra-orbital and, for the abducens nerve, an additional interdural segment. Magnetic resonance imaging is the imaging method of choice in the evaluation of the normal and pathologic ocular motor nerves. CT still plays a limited but important role in the evaluation of the intraosseous portions at the skull base and bony foramina. We describe for each segment of these cranial nerves, the normal anatomy, the most appropriate image sequences and planes, their imaging appearance and pathologic conditions. Magnetic resonance imaging with high magnetic fields is a developing and promising technique. We describe our initial experience with a Phillips 7.0 T MRI scanner in the evaluation of the brainstem segments of the OMNs. As imaging becomes more refined, an understanding of the detailed anatomy is increasingly necessary, as the demand on radiology to diagnose smaller lesions also increases.

  7. Differences in learning volitional (manual and non-volitional (posture aspects of a complex motor skill in young adult dyslexic and skilled readers.

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    Itamar Sela

    Full Text Available The 'Cerebellar Deficit Theory' of developmental dyslexia proposes that a subtle developmental cerebellar dysfunction leads to deficits in attaining 'automatic' procedures and therefore manifests as subtle motor impairments (e.g., balance control, motor skill learning in addition to the reading and phonological difficulties. A more recent version of the theory suggests a core deficit in motor skill acquisition. This study was undertaken to compare the time-course and the nature of practice-related changes in volitional (manual and non-volitional (posture motor performance in dyslexic and typical readers while learning a new movement sequence. Seventeen dyslexic and 26 skilled young adult readers underwent a three-session training program in which they practiced a novel sequence of manual movements while standing in a quiet stance position. Both groups exhibited robust and well-retained gains in speed, with no loss of accuracy, on the volitional, manual, aspects of the task, with a time-course characteristic of procedural learning. However, the dyslexic readers exhibited a pervasive slowness in the initiation of volitional performance. In addition, while typical readers showed clear and well-retained task-related adaptation of the balance and posture control system, the dyslexic readers had significantly larger sway and variance of sway throughout the three sessions and were less efficient in adapting the posture control system to support the acquisition of the novel movement sequence. These results support the notion of a non-language-related deficit in developmental dyslexia, one related to the recruitment of motor systems for effective task performance rather than to a general motor learning disability.

  8. Cardinality as a Highly Descriptive Feature in Myoelectric Pattern Recognition for Decoding Motor Volition

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    Max eOrtiz-Catalan

    2015-10-01

    Full Text Available Accurate descriptors of muscular activity play an important role in clinical practice and rehabilitation research. Such descriptors are features of myoelectric signals extracted from sliding time windows. A wide variety of myoelectric features have been used as inputs to pattern recognition algorithms that aim to decode motor volition. The output of these algorithms can then be used to control limb prostheses, exoskeletons, and rehabilitation therapies. In the present study, cardinality is introduced and compared with traditional time-domain (Hudgins’ set and other recently proposed myoelectric features (for example, rough entropy. Cardinality was found to consistently outperform other features, including those that are more sophisticated and computationally expensive, despite variations in sampling frequency, time window length, contraction dynamics, type and number of movements (single or simultaneous, and classification algorithms. Provided that the signal resolution is kept between 12 and 14 bits, cardinality improves myoelectric pattern recognition for the prediction of motion volition. This technology is instrumental for the rehabilitation of amputees and patients with motor impairments where myoelectric signals are viable. All code and data used in this work is available online within BioPatRec.

  9. A rapid method of detecting motor blocks in patients with Parkinson's disease during volitional hand movements

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    Popović Mirjana B.

    2002-01-01

    Full Text Available INTRODUCTION An algorithm to study hand movements in patients with Parkinson's disease (PD who experience temporary, involuntary inability to move a hand have been developed. In literature, this rather enigmatic phenomenon has been described in gait, speech, handwriting and tapping, and noted as motor blocks (MB or freezing episodes. Freezing refers to transient periods in which the voluntary motor activity being attempted by an individual is paused. It is a sudden, unplanned state of immobility that appears to arise from deficits in initiating or simultaneously and sequentially executing movements, in correcting inappropriate movements or in planning movements. The clinical evaluation of motor blocks is difficult because of a variability both within and between individuals and relationship of blocks to time of drug ingestion. In literature the terms freezing, motor block or motor freezing are used in parallel. AIM In clinical settings classical manifestations of Parkinson's Disease (akinesia bradykinesia, rigidity, tremor, axial motor performance and postural instability are typically evaluated. Recently, in literature, new computerized methods are suggested for their objective assessment. We propose monitoring of motor blocks during hand movements to be integrated. For this purpose we have developed a simple method that comprises PC computer, digitizing board and custom made software. Movement analysis is "off line", and the result is the data that describe the number, duration and onset of motor blocks. METHOD Hand trajectories are assessed during simple volitional self paced point-to-point planar hand movement by cordless magnetic mouse on a digitizing board (Drawing board III, 305 x 457 mm, GTCO Cal Comp Inc, Fig. 1. Testing included 8 Parkinsonian patients and 8 normal healthy controls, age matched, with unknown neurologic motor or sensory disorders, Table 1. Three kinematic indicators of motor blocks: 1 duration (MBTJ; 2 onset (t%; and 3

  10. Saccade and vestibular ocular motor adaptation.

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    Schubert, Michael C; Zee, David S

    2010-01-01

    This paper focuses on motor learning within the saccadic and vestibulo-ocular reflex (VOR) oculomotor systems, vital for our understanding how the brain keeps these subsystems calibrated in the presence of disease, trauma, and the changes that invariably accompany normal development and aging. We will concentrate on new information related to multiple time scales of saccade motor learning, adaptation of the VOR during high-velocity impulses, and the role of saccades in VOR adaptation. The role of the cerebellum in both systems is considered. Review of data involving saccade and VOR motor learning. Data supports learning within the saccadic and VOR oculomotor systems is influenced by 1). Multiple time scales, with different rates of both learning and forgetting (seconds, minutes, hours, days, and months). In the case of forgetting, relearning on a similar task may be faster. 2). Pattern of training, learning and forgetting are not similarly achieved. Different contexts require different motor behaviors and rest periods between training sessions can be important for memory consolidation. The central nervous system has the difficult task of determining where blame resides when motor performance is impaired (the credit assignment problem). Saccade and VOR motor learning takes place at multiple levels within the nervous system, from alterations in ion channel and membrane properties on single neurons, to more complex changes in neural circuit behavior and higher-level cognitive processes including prediction.

  11. Ocular Motor Function in Children with Spastic Hemiplegia Evaluated by the Ocular Motor Score.

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    Rydberg, A; Ygge, J; Olsson, M

    2017-09-01

    To assess the ocular motor functions in children with spastic hemiplegia by using the Ocular Motor Score (OMS). This study included 34 children, median age 11 years. The children were divided into 3 groups according to the underlying brain lesion; group 1 malformations, group 2 white matter damage of immaturity (WMDI), and group 3 cortical/subcortical lesions. The OMS protocol consists of 15 different subtests evaluating ocular motor functions. The OMS is divided into 2 parts, a static and a dynamic. The results from each subtest are scored 0, 0.3, 0.5, or 1, according to the level of disturbance, where 0 corresponds to normal function and 1 represents the maximum disability in the certain subtest. A total OMS (tOMS) between 0 and 15 can be obtained. The median tOMS in the whole spastic hemiplegia group was 2.5 (range 1.3-5.8). The highest median tOMS 5.2 was seen in group 1, in the children with malformations. Strabismus was found in 45% (15/34) of the children, with an equal percentage in all 3 groups. The children with spastic hemiplegia had a median tOMS of 2.7 and the highest median tOMS was seen in children with malformations. The OMS protocol is easy to use clinically and gives a quick overview of the patient´s ocular motor functions.

  12. Albinism: particular attention to the ocular motor system.

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    Hertle, Richard W

    2013-01-01

    The purpose of this report is to summarize an understanding of the ocular motor system in patients with albinism. Other than the association of vertical eccentric gaze null positions and asymmetric, (a) periodic alternating nystagmus in a large percentage of patients, the ocular motor system in human albinism does not contain unique pathology, rather has "typical" types of infantile ocular oscillations and binocular disorders. Both the ocular motor and afferent visual system are affected to varying degrees in patients with albinism, thus, combined treatment of both systems will maximize visual function.

  13. Enabling Task-Specific Volitional Motor Functions via Spinal Cord Neuromodulation in a Human With Paraplegia.

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    Grahn, Peter J; Lavrov, Igor A; Sayenko, Dimitry G; Van Straaten, Meegan G; Gill, Megan L; Strommen, Jeffrey A; Calvert, Jonathan S; Drubach, Dina I; Beck, Lisa A; Linde, Margaux B; Thoreson, Andrew R; Lopez, Cesar; Mendez, Aldo A; Gad, Parag N; Gerasimenko, Yury P; Edgerton, V Reggie; Zhao, Kristin D; Lee, Kendall H

    2017-04-01

    We report a case of chronic traumatic paraplegia in which epidural electrical stimulation (EES) of the lumbosacral spinal cord enabled (1) volitional control of task-specific muscle activity, (2) volitional control of rhythmic muscle activity to produce steplike movements while side-lying, (3) independent standing, and (4) while in a vertical position with body weight partially supported, voluntary control of steplike movements and rhythmic muscle activity. This is the first time that the application of EES enabled all of these tasks in the same patient within the first 2 weeks (8 stimulation sessions total) of EES therapy. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  14. Mechanics of mouse ocular motor plant quantified by optogenetic techniques.

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    Stahl, John S; Thumser, Zachary C; May, Paul J; Andrade, Francisco H; Anderson, Sean R; Dean, Paul

    2015-09-01

    Rigorous descriptions of ocular motor mechanics are often needed for models of ocular motor circuits. The mouse has become an important tool for ocular motor studies, yet most mechanical data come from larger species. Recordings of mouse abducens neurons indicate the mouse mechanics share basic viscoelastic properties with larger species but have considerably longer time constants. Time constants can also be extracted from the rate at which the eye re-centers when released from an eccentric position. The displacement can be accomplished by electrically stimulating ocular motor nuclei, but electrical stimulation may also activate nearby ocular motor circuitry. We achieved specific activation of abducens motoneurons through photostimulation in transgenic mice expressing channelrhodopsin in cholinergic neurons. Histology confirmed strong channelrhodopsin expression in the abducens nucleus with relatively little expression in nearby ocular motor structures. Stimulation was delivered as 20- to 1,000-ms pulses and 40-Hz trains. Relaxations were modeled best by a two-element viscoelastic system. Time constants were sensitive to stimulus duration. Analysis of isometric relaxation of isolated mouse extraocular muscles suggest the dependence is attributable to noninstantaneous decay of active forces in non-twitch fibers following stimulus offset. Time constants were several times longer than those obtained in primates, confirming that the mouse ocular motor mechanics are relatively sluggish. Finally, we explored the effects of 0.1- to 20-Hz sinusoidal photostimuli and demonstrated their potential usefulness in characterizing ocular motor mechanics, although this application will require further data on the temporal relationship between photostimulation and neuronal firing in extraocular motoneurons.

  15. Ocular Motor Function in Patients with Bilateral Vestibular Weakness

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    Seyyed Amir Hossein Ghazizadeh Hashemi

    2016-05-01

    Full Text Available Introduction: Patients with bilateral weakness (BW have many difficulties in gaze stability that interfere with their normal function. The aim of this study was to evaluate ocular motor functions in patients with BW to better understand the problem of gaze instability in these patients.   Materials and Methods: Patients were referred from the Otolaryngology Department for Vestibular Assessment to our clinic between November 2014 and March 2015. We assessed ocular motor function (gaze, saccade, and smooth pursuit in patients over the age of 18 years with BW, as verified by a caloric test.   Results: Seventy-eight patients completed all the tests. The mean age of patients was 51.9 (±15.9 years, and 47 (60% were female. Abnormal results were found in five (6.4%, 32 (41%, and seven (9% patients with respect to gaze, smooth pursuit, and saccade, respectively. There were positive but relatively weak relationships between age and ocular motor results.   Conclusion:  Patients with BW suffer from dizziness and unsteadiness. These patients have abnormal function in ocular motor (especially smooth pursuit tests. The ocular motor dysfunction is responsible for gaze instability in static positions such as standing.

  16. [A rapid detection of motor block in patients with Parkinson disease during volitional movements of the hand].

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    Popović, Mirjana B; Kostić, Vladimir; Dzoljić, Eleonora; Ercegovac, Marko

    2002-01-01

    An algorithm to study hand movements in patients with Parkinson's disease (PD) who experience temporary, involuntary inability to move a hand have been developed. In literature, this rather engimatic phenomenon has been described in gait, speech, handwriting and tapping, and noted as motor blocks (MB) or freezing episodes. Freezing refers to transient periods in which the voluntary motor activity being attempted by an individual is paused. It is a sudden, unplanned state of immobility that appears to arise from deficits in initiating or simultaneously and sequentially executing movements, in correcting inappropriate movements or in planning movements. The clinical evaluation of motor blocks is difficult because of a variability both within and between individuals and relationship of blocks to time of drug ingestion. In literature the terms freezing, motor block or motor freezing are used in parallel. In clinical settings classical manifestations of Parkinson's Disease (akinesia, bradykinesia, rigidity, tremor, axial motor performance and postural instability) are typically evaluated. Recently, in literature, new computerized methods are suggested for their objective assessment. We propose monitoring of motor blocks during hand movements to be integrated. For this purpose we have developed a simple method that comprises PC computer, digitizing board and custom made software. Movement analysis is "off line", and the result is the data that describe the number, duration and onset of motor blocks. Hand trajectories are assessed during simple volitional self paced point-to-point planar hand movement by cordless magnetic mouse on a digitizing board (Drawing board III, 305 x 457 mm, GTCO Cal Comp Inc), Fig. 1. Testing included 8 Parkinsonian patients and 8 normal healthy controls, age matched, with unknown neurologic motor or sensory disorders, Table 1. Three kinematic indicators of motor blocks: 1) duration (MBT%); 2) onset (t%); and 3) number (N) of MB episodes, allow

  17. Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method

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    Hai-peng Wang

    2017-01-01

    Full Text Available Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy. A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method. Through a series of novel design concepts, including the integration of a detecting circuit and an analog-to-digital converter, a miniaturized functional electrical stimulation circuit technique, a low-power super-regeneration chip for wireless receiving, and two wearable armbands, a prototype system has been established with reduced size, power, and overall cost. Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects, the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy. Test results showed that wrist flexion/extension, hand grasp, and finger extension could be reproduced with high accuracy and low latency. This system can build a bridge of information transmission between healthy limbs and paralyzed limbs, effectively improve voluntary participation of hemiplegic patients, and elevate efficiency of rehabilitation training.

  18. Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method.

    Science.gov (United States)

    Wang, Hai-Peng; Bi, Zheng-Yang; Zhou, Yang; Zhou, Yu-Xuan; Wang, Zhi-Gong; Lv, Xiao-Ying

    2017-01-01

    Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy. A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method. Through a series of novel design concepts, including the integration of a detecting circuit and an analog-to-digital converter, a miniaturized functional electrical stimulation circuit technique, a low-power super-regeneration chip for wireless receiving, and two wearable armbands, a prototype system has been established with reduced size, power, and overall cost. Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects, the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy. Test results showed that wrist flexion/extension, hand grasp, and finger extension could be reproduced with high accuracy and low latency. This system can build a bridge of information transmission between healthy limbs and paralyzed limbs, effectively improve voluntary participation of hemiplegic patients, and elevate efficiency of rehabilitation training.

  19. Real-time and wearable functional electrical stimulation system for volitional hand motor function control using the electromyography bridge method

    Science.gov (United States)

    Wang, Hai-peng; Bi, Zheng-yang; Zhou, Yang; Zhou, Yu-xuan; Wang, Zhi-gong; Lv, Xiao-ying

    2017-01-01

    Voluntary participation of hemiplegic patients is crucial for functional electrical stimulation therapy. A wearable functional electrical stimulation system has been proposed for real-time volitional hand motor function control using the electromyography bridge method. Through a series of novel design concepts, including the integration of a detecting circuit and an analog-to-digital converter, a miniaturized functional electrical stimulation circuit technique, a low-power super-regeneration chip for wireless receiving, and two wearable armbands, a prototype system has been established with reduced size, power, and overall cost. Based on wrist joint torque reproduction and classification experiments performed on six healthy subjects, the optimized surface electromyography thresholds and trained logistic regression classifier parameters were statistically chosen to establish wrist and hand motion control with high accuracy. Test results showed that wrist flexion/extension, hand grasp, and finger extension could be reproduced with high accuracy and low latency. This system can build a bridge of information transmission between healthy limbs and paralyzed limbs, effectively improve voluntary participation of hemiplegic patients, and elevate efficiency of rehabilitation training. PMID:28250759

  20. Ocular motor and sensory function in Parkinson's disease.

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    Almer, Zina; Klein, Kathyrn S; Marsh, Laura; Gerstenhaber, Melissa; Repka, Michael X

    2012-01-01

    To evaluate the effect of dopaminergic medication and deep brain stimulation on ocular function in Parkinson's disease (PD) and to measure vision-related quality of life in subjects with PD. Prospective, comparative case series. Twenty-seven PD and 16 control subjects were recruited. Visual acuity, ocular motor function, convergence, and vision-related quality of life using the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) were measured. Visual sensory and motor measurements were obtained during the on and off states of PD dopaminergic treatment. Convergence ability and vision-related quality of life. The PD subjects had a mean age of 58.8 years; 30% were female. Their mean duration of PD was 10.9 ± 6.8 years. The control subjects had a mean age of 61.6 years; 56% were female. There was no difference in visual acuity, contrast sensitivity, or color vision of the PD subjects in their on state compared with controls. Convergence amplitudes measured with base-out prism were significantly poorer in PD subjects in their on state compared with controls (24.1 ± 8 Δ vs. 14.8 ± 10.3 Δ; P = 0.003). The mean composite VFQ-25 score was significantly worse in the PD subjects compared with the controls (87.1 ± 8.69 vs. 96.6 ± 3.05; P = 0.0001). Comparing the PD subjects in their on with their off states, there was no difference in distance exodeviation, near exodeviation, or ocular ductions. Mean convergence amplitudes and near point of convergence were better in the on state compared with the off state: 14.8 ± 10.3 Δ versus 10.7 ± 9.0 Δ (P = 0.0006) and 13.1 ± 9.1 cm versus 18.1 ± 12.2 cm (P = 0.002), respectively. Convergence ability is significantly poorer in PD subjects in both the on and off states compared with controls, but improves significantly with systemic dopaminergic treatment. Ocular motor function in PD subjects fluctuates in response to treatment, which complicates ophthalmic management. Parkinson's disease subjects have a

  1. Bedside Tested Ocular Motor Disorders in Multiple Sclerosis Patients

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    G. Servillo

    2014-01-01

    Full Text Available Background/Aims. Ocular motor disorders (OMDs are a common feature of multiple sclerosis (MS. In clinical practice, if not reported by patients, OMDs are often underdiagnosed and their prevalence is underestimated. Methods. We studied 163 patients (125 women, 76.7%, 38 men, 23.3%; median age 45.0 years; median disease duration 10 years; median EDSS 3.5 with definite MS (n=150, 92% or clinically isolated syndrome (n=13, 8% who underwent a thorough clinical examination of eye movements. Data on localization of previous relapses, MS subtype, and MRI findings were collected and analyzed. Results. Overall, 111/163 (68.1% patients showed at least one abnormality of eye movement. Most frequent OMDs were impaired smooth pursuit (42.3%, saccadic dysmetria (41.7%, unilateral internuclear ophthalmoplegia (14.7%, slowing of saccades (14.7%, skew deviation (13.5%, and gaze evoked nystagmus (13.5%. Patients with OMDs had more severe disability (P=0.0005 and showed more frequently infratentorial MRI lesions (P=0.004. Localization of previous relapses was not associated with presence of OMDs. Conclusion. OMDs are frequent in patients with stable (no relapses MS. A precise bedside examination of eye motility can disclose abnormalities that imply the presence of subclinical MS lesions and may have a substantial impact on definition of the diagnosis and on management of MS patients.

  2. Emotion, Motivation und Volition

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    Ulich, Dieter

    1996-01-01

    Emotion, Motivation und Volition / D. Ulich ; V. Brandstätter ; P. M. Gollwitzer. - In: Psychologie / hrsg. von Dietrich Dörner ... - 2., überarb. und erw. Aufl. - Stuttgart u.a. : Kohlhammer, 1996. - S. 115-135

  3. Ocular motor disturbances in autism spectrum disorders: Systematic review and comprehensive meta-analysis.

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    Johnson, Beth P; Lum, Jarrad A G; Rinehart, Nicole J; Fielding, Joanne

    2016-10-01

    There has been considerable focus placed on how individuals with autism spectrum disorder (ASD) visually perceive and attend to social information, such as facial expressions or social gaze. The role of eye movements is inextricable from visual perception, however this aspect is often overlooked. We performed a series of meta-analyses based on data from 28 studies of eye movements in ASD to determine whether there is evidence for ocular motor dysfunction in ASD. Tasks assessed included visually-guided saccade tasks, gap/overlap, anti-saccade, pursuit tasks and ocular fixation. These analyses revealed evidence for ocular motor dysfunction in ASD, specifically relating to saccade dysmetria, difficulty inhibiting saccades and impaired tracking of moving targets. However there was no evidence for deficits relating to initiating eye movements, or engaging and disengaging from simple visual targets. Characterizing ocular motor abnormalities in ASD may provide insight into the functional integrity of brain networks in ASD across development, and assist our understanding of visual and social attention in ASD. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. A Brief Vestibular/Ocular Motor Screening (VOMS) Assessment to Evaluate Concussions

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    Mucha, Anne; Collins, Michael W.; Elbin, R.J.; Furman, Joseph M.; Troutman-Enseki, Cara; DeWolf, Ryan M.; Marchetti, Greg; Kontos, Anthony P.

    2014-01-01

    Background Vestibular and ocular motor impairments and symptoms have been documented in patients with sport-related concussions. However, there is no current brief clinical screen to assess and monitor these issues. Purpose To describe and provide initial data for the internal consistency and validity of a brief clinical screening tool for vestibular and ocular motor impairments and symptoms after sport-related concussions. Study Design Cross-sectional study; Level of evidence, 2. Methods Sixty-four patients, aged 13.9 ± 2.5 years and seen approximately 5.5 ± 4.0 days after a sport-related concussion, and 78 controls were administered the Vestibular/Ocular Motor Screening (VOMS) assessment, which included 5 domains: (1) smooth pursuit, (2) horizontal and vertical saccades, (3) near point of convergence (NPC) distance, (4) horizontal vestibular ocular reflex (VOR), and (5) visual motion sensitivity (VMS). Participants were also administered the Post-Concussion Symptom Scale (PCSS). Results Sixty-one percent of patients reported symptom provocation after at least 1 VOMS item. All VOMS items were positively correlated to the PCSS total symptom score. The VOR (odds ratio [OR], 3.89; P concussed group. An NPC distance ≥5 cm and any VOMS item symptom score ≥2 resulted in an increase in the probability of correctly identifying concussed patients of 38% and 50%, respectively. Receiver operating characteristic curves supported a model including the VOR, VMS, NPC distance, and ln(age) that resulted in a high predicted probability (area under the curve = 0.89) for identifying concussed patients. Conclusion The VOMS demonstrated internal consistency as well as sensitivity in identifying patients with concussions. The current findings provide preliminary support for the utility of the VOMS as a brief vestibular/ocular motor screen after sport-related concussions. The VOMS may augment current assessment tools and may serve as a single component of a comprehensive approach

  5. Characterization of ocular motor deficits in congenital facial weakness: Moebius and related syndromes.

    Science.gov (United States)

    Rucker, Janet C; Webb, Bryn D; Frempong, Tamiesha; Gaspar, Harald; Naidich, Thomas P; Jabs, Ethylin Wang

    2014-04-01

    Congenital facial weakness is present in a heterogeneous group of conditions. Among them is Moebius syndrome, which has been defined as a disorder with congenital, non-progressive facial weakness and limited abduction of one or both eyes. It is typically attributed to agenesis of the abducens and facial cranial nerves. This paper details ocular motor findings of 40 subjects (23 months to 64 years; 24 females, 16 males) with congenital facial weakness: 38 presented at a Moebius Syndrome Conference and two were clinic patients. A new classification scheme of patterns based on ocular motor phenotype is presented. Of 40 subjects, 37 had bilateral and three had unilateral facial weakness. The most common ocular motor pattern (Pattern 1, n=17, 43%) was bilateral horizontal gaze palsy with intact vertical range. Pattern 2 (n=10, 26%) was bilateral horizontal gaze palsy with variable vertical limitations. Pattern 3, which was rare, was isolated abduction deficits (n=2, 5%). Others had full motility range and did not meet minimal criteria for the diagnosis of Moebius syndrome (Pattern 4, n=10, 26%). One subject was too severely affected to characterize. Abnormal vertical smooth pursuit was present in 17 (57%) of 30 subjects: nine with Pattern 1, five with Pattern 2, and three with Pattern 4. Abnormal vertical saccades were present in 10 (34%) of 29 subjects. Vertical saccades appeared slow in nine: six with Pattern 1 and three with Pattern 2. Vertical saccades were absent in one subject with Pattern 2. Abnormal vertical optokinetic nystagmus was present in 19 (68%) of 28 subjects: 10 with Pattern 1, six with Pattern 2, one with Pattern 3, and two with Pattern 4. Reduced convergence was present in 19 (66%) of 29 subjects: nine with Pattern 1, six with Pattern 2, one with Pattern 3, and three with Pattern 4. The most common pattern of ocular motor deficit in Moebius syndrome is bilateral horizontal gaze palsy from pontine abducens nuclear defects, rather than abducens nerve

  6. Characterization of ocular motor deficits in congenital facial weakness: Moebius and related syndromes

    Science.gov (United States)

    Webb, Bryn D.; Frempong, Tamiesha; Gaspar, Harald; Naidich, Thomas P.; Jabs, Ethylin Wang

    2014-01-01

    Congenital facial weakness is present in a heterogeneous group of conditions. Among them is Moebius syndrome, which has been defined as a disorder with congenital, non-progressive facial weakness and limited abduction of one or both eyes. It is typically attributed to agenesis of the abducens and facial cranial nerves. This paper details ocular motor findings of 40 subjects (23 months to 64 years; 24 females, 16 males) with congenital facial weakness: 38 presented at a Moebius Syndrome Conference and two were clinic patients. A new classification scheme of patterns based on ocular motor phenotype is presented. Of 40 subjects, 37 had bilateral and three had unilateral facial weakness. The most common ocular motor pattern (Pattern 1, n = 17, 43%) was bilateral horizontal gaze palsy with intact vertical range. Pattern 2 (n = 10, 26%) was bilateral horizontal gaze palsy with variable vertical limitations. Pattern 3, which was rare, was isolated abduction deficits (n = 2, 5%). Others had full motility range and did not meet minimal criteria for the diagnosis of Moebius syndrome (Pattern 4, n = 10, 26%). One subject was too severely affected to characterize. Abnormal vertical smooth pursuit was present in 17 (57%) of 30 subjects: nine with Pattern 1, five with Pattern 2, and three with Pattern 4. Abnormal vertical saccades were present in 10 (34%) of 29 subjects. Vertical saccades appeared slow in nine: six with Pattern 1 and three with Pattern 2. Vertical saccades were absent in one subject with Pattern 2. Abnormal vertical optokinetic nystagmus was present in 19 (68%) of 28 subjects: 10 with Pattern 1, six with Pattern 2, one with Pattern 3, and two with Pattern 4. Reduced convergence was present in 19 (66%) of 29 subjects: nine with Pattern 1, six with Pattern 2, one with Pattern 3, and three with Pattern 4. The most common pattern of ocular motor deficit in Moebius syndrome is bilateral horizontal gaze palsy from pontine abducens nuclear defects, rather than abducens

  7. Role of the flocculus of the cerebellum in motor learning of the vestibulo-ocular reflex

    Science.gov (United States)

    Highstein, S. M.

    1998-01-01

    Structure-function studies at the systems level are an effective method for understanding the relationship of the central nervous system to behavior. Motor learning or adaptation of the vestibulo-ocular reflex is a clear example wherein this approach has been productive. During a vestibulo-ocular reflex the brain converts a head velocity signal, transduced through the vestibular semicircular canals, into an eye movement command delivered to the extraocular muscles. If the viewed target remains on the fovea of the retina, the reflex is compensatory, and its gain, eye velocity/head velocity, is one. When the image of the viewed object slips across the retina, visual acuity decreases, and the gain of the reflex, which is no longer one, is plastically adapted or adjusted until retinal stability is restored. The anatomic substrate for this plasticity thus involves brain structures in which visual-vestibular interaction can potentially occur, as well as vestibular and visual sensory and oculomotor motor structures. Further, it has been known for many years that removal of the flocculus of the cerebellum permanently precludes further vestibulo-ocular reflex adaptation, demonstrating the involvement of the cerebellum in this behavior. Maekawa and Simpson (J Neurophysiol 1973;36: 649-66) discovered that one visual input to the flocculus involved the accessory optic system and the inferior olive. Ensuing work has demonstrated that the visual signals used to adapt the vestibulo-ocular reflex are transmitted by this accessory optic system to the flocculus and subsequently to brain stem structures involved in vestibulo-ocular reflex plasticity. Presently the inclusive list of anatomic sites involved in vestibulo-ocular reflex circuitry and its adaptive plasticity is small. Our laboratory continues to believe that this behavior should be caused by interactions within this small class of neurons. By studying each class of identified neuron and its interactions with others within

  8. Disrupted Saccade Control in Chronic Cerebral Injury: Upper Motor Neuron-Like Disinhibition in the Ocular Motor System.

    Science.gov (United States)

    Rizzo, John-Ross; Hudson, Todd E; Abdou, Andrew; Lui, Yvonne W; Rucker, Janet C; Raghavan, Preeti; Landy, Michael S

    2017-01-01

    Saccades rapidly direct the line of sight to targets of interest to make use of the high acuity foveal region of the retina. These fast eye movements are instrumental for scanning visual scenes, foveating targets, and, ultimately, serve to guide manual motor control, including eye-hand coordination. Cerebral injury has long been known to impair ocular motor control. Recently, it has been suggested that alterations in control may be useful as a marker for recovery. We measured eye movement control in a saccade task in subjects with chronic middle cerebral artery stroke with both cortical and substantial basal ganglia involvement and in healthy controls. Saccade latency distributions were bimodal, with an early peak at 60 ms (anticipatory saccades) and a later peak at 250 ms (regular saccades). Although the latencies corresponding to these peaks were the same in the two groups, there were clear differences in the size of the peaks. Classifying saccade latencies relative to the saccade "go signal" into anticipatory (latencies up to 80 ms), "early" (latencies between 80 and 160 ms), and "regular" types (latencies longer than 160 ms), stroke subjects displayed a disproportionate number of anticipatory saccades, whereas control subjects produced the majority of their saccades in the regular range. We suggest that this increase in the number of anticipatory saccade events may result from a disinhibition phenomenon that manifests as an impairment in the endogenous control of ocular motor events (saccades) and interleaved fixations. These preliminary findings may help shed light on the ocular motor deficits of neurodegenerative conditions, results that may be subclinical to an examiner, but clinically significant secondary to their functional implications.

  9. Volition and the Function of Consciousness

    Science.gov (United States)

    Lau, Hakwan C.

    What are the psychological functions that could only be performed consciously? People have intuitively assumed that many acts of volition are not influenced by unconscious information. These acts range from simple examples such as making a spontaneous motor movement, to higher cognitive control. How ever, the available evidence suggests that under suitable conditions, unconscious information can influence these behaviors and the underlying neural mechanisms. One possibility is that stimuli that are consciously perceived tend to yield strong signals in the brain, which makes us think that consciousness has the function of such strong signals. However, if we could create conditions where the stimuli could yield strong signals but not the conscious experience of perception, perhaps we would find that such stimuli are just as effective in influencing volitional be havior. Future studies that focus on clarifying this issue may tell us what the defining functions of consciousness are.

  10. Single motor unit activity in human extraocular muscles during the vestibulo-ocular reflex

    Science.gov (United States)

    Weber, Konrad P; Rosengren, Sally M; Michels, Rike; Sturm, Veit; Straumann, Dominik; Landau, Klara

    2012-01-01

    Motor unit activity in human eye muscles during the vestibulo-ocular reflex (VOR) is not well understood, since the associated head and eye movements normally preclude single unit recordings. Therefore we recorded single motor unit activity following bursts of skull vibration and sound, two vestibular otolith stimuli that elicit only small head and eye movements. Inferior oblique (IO) and inferior rectus (IR) muscle activity was measured in healthy humans with concentric needle electrodes. Vibration elicited highly synchronous, short-latency bursts of motor unit activity in the IO (latency: 10.5 ms) and IR (14.5 ms) muscles. The activation patterns of the two muscles were similar, but reciprocal, with delayed activation of the IR muscle. Sound produced short-latency excitation of the IO muscle (13.3 ms) in the eye contralateral to the stimulus. Simultaneous needle and surface recordings identified the IO as the muscle of origin of the vestibular evoked myogenic potential (oVEMP) thus validating the physiological basis of this recently developed clinical test of otolith function. Single extraocular motor unit recordings provide a window into neural activity in humans that can normally only be examined using animal models and help identify the pathways of the translational VOR from otoliths to individual eye muscles. PMID:22526888

  11. Volitional Control of Neuromagnetic Coherence

    Directory of Open Access Journals (Sweden)

    Matthew D Sacchet

    2012-12-01

    Full Text Available Coherence of neural activity between circumscribed brain regions has been implicated as an indicator of intracerebral communication in various cognitive processes. While neural activity can be volitionally controlled with neurofeedback, the volitional control of coherence has not yet been explored. Learned volitional control of coherence could elucidate mechanisms of associations between cortical areas and its cognitive correlates and may have clinical implications. Neural coherence may also provide a signal for brain-computer interfaces (BCI. In the present study we used the Weighted Overlapping Segment Averaging (WOSA method to assess coherence between bilateral magnetoencephalograph (MEG sensors during voluntary digit movement as a basis for BCI control. Participants controlled an onscreen cursor, with a success rate of 124 of 180 (68.9%, sign-test p < 0.001 and 84 out of 100 (84%, sign-test p < 0.001. The present findings suggest that neural coherence may be volitionally controlled and may have specific behavioral correlates.

  12. The evolutionary origins of volition

    OpenAIRE

    Christensen, Dr Wayne

    2006-01-01

    It appears to be a straightforward implication of distributed cognition principles that there is no integrated executive control system (e.g. Brooks 1991, Clark 1997). If distributed cognition is taken as a credible paradigm for cognitive science this in turn presents a challenge to volition because the concept of volition assumes integrated information processing and action control. For instance the process of forming a goal should integrate information about the available action options. If...

  13. Effects of visual processing and congenital nystagmus on visually guided ocular motor behaviour.

    Science.gov (United States)

    Pel, Johan; Does, Lisette Van Der; Boot, Fleur; Faber, Tjeerd De; Steen-Kant, Sanny Van Der; Willemsen, Sten; Steen, Hans Van Der

    2011-04-01

    The aim of this study was to compare visually guided ocular motor behaviour in children with visual processing and/or motor deficits with an age-matched comparison group and an adult group. Visual stimuli were shown to 28 children with visual processing and/or motor deficits (11 females, 17 males; mean age 7y 5mo, SD 2y 9mo, range 2-14y;) and an age-matched comparison group of 213 typically developing children (115 females, 98 males; mean age 5y 8mo, SD 3y 5mo, range 0-12y). The adult group consisted of nine females and two males with (mean age of 24y 4mo, SD 4y 8mo). Individuals who had a likely diagnosis of cerebral visual impairment (CVI), an opticopathy with unknown location, nystagmus, glaucoma, or a cataract were included in the study. Exclusion criteria were a visual acuity below 0.2, a developmental age under 1 year, and the presence of brain tumours, autism, and anxiety disorders. Orientating eye movements to large cartoons were quantified using the reaction time to fixation (RTF) and gaze fixation area (GFA). A Mann-Whitney U test was used to compare the differences between groups and Bonferroni post-hoc testing was used to analyse age dependence of RTF and GFA values within the comparison group. Individuals with CVI showed significantly prolonged RTF values; those with congenital nystagmus showed significantly increased GFA values. In the comparison group, RTF was significantly longer in children under the age of 2 years than in children aged 4 years and older (290 and 200 ms respectively; p Journal compilation © Mac Keith Press 2010.

  14. The Intersection between Ocular and Manual Motor Control: Eye–Hand Coordination in Acquired Brain Injury

    Directory of Open Access Journals (Sweden)

    John-Ross Rizzo

    2017-06-01

    Full Text Available Acute and chronic disease processes that lead to cerebral injury can often be clinically challenging diagnostically, prognostically, and therapeutically. Neurodegenerative processes are one such elusive diagnostic group, given their often diffuse and indolent nature, creating difficulties in pinpointing specific structural abnormalities that relate to functional limitations. A number of studies in recent years have focused on eye–hand coordination (EHC in the setting of acquired brain injury (ABI, highlighting the important set of interconnected functions of the eye and hand and their relevance in neurological conditions. These experiments, which have concentrated on focal lesion-based models, have significantly improved our understanding of neurophysiology and underscored the sensitivity of biomarkers in acute and chronic neurological disease processes, especially when such biomarkers are combined synergistically. To better understand EHC and its connection with ABI, there is a need to clarify its definition and to delineate its neuroanatomical and computational underpinnings. Successful EHC relies on the complex feedback- and prediction-mediated relationship between the visual, ocular motor, and manual motor systems and takes advantage of finely orchestrated synergies between these systems in both the spatial and temporal domains. Interactions of this type are representative of functional sensorimotor control, and their disruption constitutes one of the most frequent deficits secondary to brain injury. The present review describes the visually mediated planning and control of eye movements, hand movements, and their coordination, with a particular focus on deficits that occur following neurovascular, neurotraumatic, and neurodegenerative conditions. Following this review, we also discuss potential future research directions, highlighting objective EHC as a sensitive biomarker complement within acute and chronic neurological disease processes.

  15. Human volition: towards a neuroscience of will.

    Science.gov (United States)

    Haggard, Patrick

    2008-12-01

    The capacity for voluntary action is seen as essential to human nature. Yet neuroscience and behaviourist psychology have traditionally dismissed the topic as unscientific, perhaps because the mechanisms that cause actions have long been unclear. However, new research has identified networks of brain areas, including the pre-supplementary motor area, the anterior prefrontal cortex and the parietal cortex, that underlie voluntary action. These areas generate information for forthcoming actions, and also cause the distinctive conscious experience of intending to act and then controlling one's own actions. Volition consists of a series of decisions regarding whether to act, what action to perform and when to perform it. Neuroscientific accounts of voluntary action may inform debates about the nature of individual responsibility.

  16. Institutional profile: integrated center for research and treatment of vertigo, balance and ocular motor disorders.

    Science.gov (United States)

    Brandt, Thomas; Zwergal, Andreas; Jahn, Klaus; Strupp, Michael

    2010-01-01

    In 2009 the German BMBF (German Ministry of Education and Research) established an Integrated Center for Research and Treatment (IFB(LMU)) of Vertigo, Balance and Ocular Motor Disorders in Munich. After the 10-year period of funding by the BMBF, it is envisioned that the (IFB(LMU)) will continue over the long term with the joint support of the University Hospital, the Medical Faculty, and the Bavarian State. Vertigo is one of the most common complaints in medicine. Despite its high prevalence, patients with vertigo generally receive either inappropriate or inadequate treatment. This deplorable situation is internationally well known and its causes are multiple: insufficient interdisciplinary cooperation, no standardized diagnostics and therapy, the failure to translate findings of basic science into clinical applications, and the scarcity of clinical multicenter studies. The (IFB(LMU)) will constitute a suitable tool with which these structural, clinical, and scientific deficits can be overcome. It will also make possible the establishment of an international interdisciplinary referral center. Munich has become the site of a unique concentration of leading experts on vertigo, balance and ocular motor disorders, both in the clinical and basic sciences. Academic structures have paved the way for the creation of an interdisciplinary horizontal network that also allows structured, vertical academic career paths via the Bachelor's and Master's degree programs in Neuroscience, a Graduate School of Systemic Neurosciences, and the Munich Center for Neurosciences - Brain and Mind. The (IFB(LMU)) has the following objectives as regards structure and content: to create an independent patient-oriented clinical research center under the auspices of the Medical Faculty but with autonomous administration and budget; to overcome existing clinical and academic barriers separating the traditional specializations; to establish a standardized interdisciplinary longitudinal and

  17. Fixational saccades reflect volitional action preparation.

    Science.gov (United States)

    Watanabe, Masayuki; Matsuo, Yuka; Zha, Ling; Munoz, Douglas P; Kobayashi, Yasushi

    2013-07-01

    Human volitional actions are preceded by preparatory processes, a critical mental process of cognitive control for future behavior. Volitional action preparation is regulated by large-scale neural circuits including the cerebral cortex and the basal ganglia. Because volitional action preparation is a covert process, the network dynamics of such neural circuits have been examined by neuroimaging and recording event-related potentials. Here, we examined whether such covert processes can be measured by the overt responses of fixational saccades (including microsaccades), the largest miniature eye movements that occur during eye fixation. We analyzed fixational saccades while adult humans maintained fixation on a central visual stimulus as they prepared to generate a volitional saccade in response to peripheral stimulus appearance. We used the antisaccade paradigm, in which subjects generate a saccade toward the opposite direction of a peripheral stimulus. Appropriate antisaccade performance requires the following two aspects of volitional control: 1) facilitation of saccades away from the stimulus and 2) suppression of inappropriate saccades toward the stimulus. We found that fixational saccades that occurred before stimulus appearance reflected the dual preparatory states of saccade facilitation and suppression and correlated with behavioral outcome (i.e., whether subjects succeeded or failed to cancel inappropriate saccades toward the stimulus). Moreover, fixational saccades explained a large proportion of individual differences in behavioral performance (poor/excellent) across subjects. These results suggest that fixational saccades predict the outcome of future volitional actions and may be used as a potential biomarker to detect people with difficulties in volitional action preparation.

  18. Development of Vestibular Stochastic Resonance as a Sensorimotor Countermeasure: Improving Otolith Ocular and Motor Task Responses

    Science.gov (United States)

    Mulavara, Ajitkumar; Fiedler, Matthew; DeDios,Yiri E.; Galvan, Raquel; Bloomberg, Jacob; Wood, Scott

    2011-01-01

    Astronauts experience disturbances in sensorimotor function after spaceflight during the initial introduction to a gravitational environment, especially after long-duration missions. Stochastic resonance (SR) is a mechanism by which noise can assist and enhance the response of neural systems to relevant, imperceptible sensory signals. We have previously shown that imperceptible electrical stimulation of the vestibular system enhances balance performance while standing on an unstable surface. The goal of our present study is to develop a countermeasure based on vestibular SR that could improve central interpretation of vestibular input and improve motor task responses to mitigate associated risks.

  19. The effect of visual therapy on the ocular motor control of seven- to eight-year-old children with developmental coordination disorder (DCD).

    Science.gov (United States)

    Coetzee, Dané; Pienaar, Anita E

    2013-11-01

    The aims of this study were to determine the extent of ocular, motor control problems and the effect of visual therapy on such problems, among seven- to eight-year-old children diagnosed with DCD. Thirty-two, children with a mean age of 95.66 months (SD ± 3.54) participated in the study. The MABC was used to classify children into DCD categories (motor control. A two-group pre-test-post-test, cross-over design was followed with a retention test two years, thereafter to determine the lasting effect of the visual therapy, intervention. The 18-week visual therapy programme was executed once a week, for 40 min during school hours, after which the two groups were, crossed over. Percentages of ocular motor control problems ranging, between 6.25% and 93.75% were found in both the groups before participating, in the visual therapy programme, with the highest percentage problems found, in visual pursuit with the left eye. Visual therapy contributed to a, significant improvement of 75-100% in visual pursuit, fixation, ocular, alignment and convergence, with significant lasting effects (pmotor control. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Rethinking the Study of Volition for Clinical Use.

    Science.gov (United States)

    Torres, Elizabeth B

    2016-01-01

    Volition, the acquired voluntary control of our actions (at will), requires from birth to development and beyond a proper balance across multiple layers of the nervous systems. These levels range from the autonomic, to the automatic, to the voluntary control level, providing as well taxonomy with phylogenetic order of appearance in evolution. In the past few decades of movement research at the behavioral and systems levels, there has been a paucity of studies focusing on the possible contributions of involuntary movements to volitional control. Moreover, the work focusing on voluntary behavior has given us a valuable body of knowledge about constrained and highly over practiced activities while work involving unrestrained, naturalistic behaviors remains scarce. Perhaps in making theoretical assumptions about our data acquisition and analyses without properly empirically verifying, these assumptions have left us with a somewhat skewed notion of how we think the brain may be realizing the neural control of bodily motions; a notion that does not exactly correspond to the outcome of the extant empirical work assessing unrestrained movements as the nervous system acquires them and modifies skillful behaviors on demand. This chapter takes advantage of new technological advances and new analytics to invite rethinking some of the problems that we study in movement science by enforcing somewhat oversimplified assumptions on the data that we model, acquire, and analyze. I show that by relaxing our a priori assumptions of normality, linearity and stationarity in data from biophysical rhythms of the nervous systems, we would gain better insights into the motor phenomena. Further, we would shy away from a "self-fulfilling prophesy" paradigm with a tendency to a priori handcraft the outcome of our inquiry. The new lens to study natural movements and their control includes as well involuntary motions that take place largely beneath deliberate awareness. I present examples of

  1. A Positive Vestibular/Ocular Motor Screening (VOMS) Is Associated With Increased Recovery Time After Sports-Related Concussion in Youth and Adolescent Athletes.

    Science.gov (United States)

    Anzalone, Anthony J; Blueitt, Damond; Case, Tami; McGuffin, Tiffany; Pollard, Kalyssa; Garrison, J Craig; Jones, Margaret T; Pavur, Robert; Turner, Stephanie; Oliver, Jonathan M

    2017-02-01

    Vestibular and ocular motor impairments are routinely reported in patients with sports-related concussion (SRC) and may result in delayed return to play (RTP). The Vestibular/Ocular Motor Screening (VOMS) assessment has been shown to be consistent and sensitive in identifying concussion when used as part of a comprehensive examination. To what extent these impairments or symptoms are associated with length of recovery is unknown. To examine whether symptom provocation or clinical abnormality in specific domains of the VOMS results in protracted recovery (time from SRC to commencement of RTP protocol). Cohort study (prognosis); Level of evidence, 2. A retrospective chart review was conducted of 167 patients (69 girls, 98 boys; mean ± SD age, 15 ± 2 years [range, 11-19 years]) presenting with SRC in 2014. During the initial visit, VOMS was performed in which symptom provocation or clinical abnormality (eg, unsmooth eye movements) was documented by use of a dichotomous scale (0 = not present, 1 = present). The VOMS used in this clinic consisted of smooth pursuits (SMO_PUR), horizontal and vertical saccades (HOR_SAC and VER_SAC), horizontal and vertical vestibular ocular reflex (HOR_VOR and VER_VOR), near point of convergence (NPC), and accommodation (ACCOM). Domains were also categorized into ocular motor (SMO_PUR, HOR_SAC, VER_SAC, NPC, ACCOM) and vestibular (HOR_VOR, VER_VOR). Cox proportional hazard models were used to explore the relationship between the domains and recovery. Alpha was set at P ≤ .05. Symptom provocation and/or clinical abnormality in all domains except NPC ( P = .107) and ACCOM ( P = .234) delayed recovery (domain, hazard ratio [95% CI]: SMO_PUR, 0.65 [0.47-0.90], P = .009; HOR_SAC, 0.68 [0.50-0.94], P = .018; VER_SAC, 0.55 [0.40-0.75], P study may lead to more effective prognosis of concussion in youth and adolescents.

  2. Volitional Strategies and Social Anxiety among College Students

    Science.gov (United States)

    Shepherd, Robin-Marie

    2006-01-01

    This study administered the Academic Volitional Strategy Inventory to investigate volitional strategies amongst socially anxious college students. Volitional strategies regulate motivation and emotion to aid in the achievement of academic tasks. It was important to examine this phenomenon based upon the premise that socially anxious students have…

  3. Individuality of breathing during volitional moderate hyperventilation.

    Science.gov (United States)

    Besleaga, Tudor; Blum, Michaël; Briot, Raphaël; Vovc, Victor; Moldovanu, Ion; Calabrese, Pascale

    2016-01-01

    The aim of this study is to investigate the individuality of airflow shapes during volitional hyperventilation. Ventilation was recorded on 18 healthy subjects following two protocols: (1) spontaneous breathing (SP1) followed by a volitional hyperventilation at each subject's spontaneous (HVSP) breathing rate, (2) spontaneous breathing (SP2) followed by hyperventilation at 20/min (HV20). HVSP and HV20 were performed at the same level of hypocapnia: end tidal CO2 (FETCO2) was maintained at 1% below the spontaneous level. At each breath, the tidal volume (VT), the breath (TTOT), the inspiratory (TI) and expiratory durations, the minute ventilation, VT/TI, TI/TTOT and the airflow shape were quantified by harmonic analysis. Under different conditions of breathing, we test if the airflow profiles of the same individual are more similar than airflow profiles between individuals. Minute ventilation was not significantly different between SP1 (6.71 ± 1.64 l·min(-1)) and SP2 (6.57 ± 1.31 l·min(-1)) nor between HVSP (15.88 ± 4.92 l·min(-1)) and HV20 (15.87 ± 4.16 l·min(-1)). Similar results were obtained for FETCO2 between SP1 (5.06 ± 0.54 %) and SP2 (5.00 ± 0.51%), and HVSP (4.07 ± 0.51%) and HV20 (3.88 ± 0.42%). Only TI/TTOT remained unchanged in all four conditions. Airflow shapes were similar when comparing SP1-SP2, HVSP-HV20, and SP1-HVSP but not similar when comparing SP2-HV20. These results suggest the existence of an individuality of airflow shape during volitional hyperventilation. We conclude that volitional ventilation alike automatic breathing follows inherent properties of the ventilatory system. Registered by Pascale Calabrese on ClinicalTrials.gov, # NCT01881945.

  4. Ocular Hypertension

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Ocular Hypertension Sections What Is Ocular Hypertension? Ocular Hypertension Causes ... Hypertension Diagnosis Ocular Hypertension Treatment What Is Ocular Hypertension? Leer en Español: ¿Qué Es la Hipertensión Ocular? ...

  5. Ocular Melanoma

    Science.gov (United States)

    ... Español Eye Health / Eye Health A-Z Ocular Melanoma Sections What is Ocular Melanoma? Ocular Melanoma Causes ... Melanoma Diagnosis Ocular Melanoma Treatment What is Ocular Melanoma? Leer en Español: ¿Qué Es el Melanoma Ocular? ...

  6. Self-leadership and volition: distinct and potentially supplemental constructs?

    Science.gov (United States)

    Heiss, Christian; Ziegler, Matthias; Engbert, Kai; Gröpel, Peter; Brand, Ralf

    2010-10-01

    Self-leadership and volition are conceptually similar concepts. Both propose self-influence strategies that aim to improve the motivation and self-direction necessary to perform well. The present study assesses whether self-leadership strategies maintain construct-specific variance when compared with the similar strategies of volition. Results from a questionnaire study (N=320) indicate that self-leadership and volitional strategies are distinguishable and only moderately (r = .33) correlated. Self-leadership, therefore, supplements volition during goal attainment. Findings are discussed in light of the Rubicon model of action phases.

  7. Training to improve volitional muscle activity in clinically paralyzed muscles for neuroprosthesis control.

    Science.gov (United States)

    Moss, Christa W; Kilgore, Kevin L; Peckham, P Hunter

    2011-01-01

    Neuroprostheses are devices that use electrical stimulation to activate paralyzed muscles in a coordinated manner to restore functional movements. These systems utilize a voluntarily-generated command signal for control of function. Current command signals include electromyographic (EMG) activity from muscles above the injury level that remain under volitional control. In individuals with cervical level spinal cord injury (SCI), these signal sources are limited in number. Our recent research suggests that volitional muscle activity from below the injury level in individuals with motor complete spinal cord injury may be a viable source of command information. The signals from these muscles are small, and therefore the goal of this study is to determine if training using visual feedback can improve the quality of these muscle signals. Results to date indicate that training with visual feedback can increase both the magnitude and consistency of EMG signals in clinically paralyzed muscles.

  8. The ocular motor features of adult-onset alexander disease: a case and review of the literature.

    Science.gov (United States)

    Pfeffer, Gerald; Abegg, Mathias; Vertinsky, A Talia; Ceccherini, Isabella; Caroli, Francesco; Barton, Jason J S

    2011-06-01

    A 51-year-old Chinese man presented with gaze-evoked nystagmus, impaired smooth pursuit and vestibular ocular reflex cancellation, and saccadic dysmetria, along with a family history suggestive of late-onset autosomal dominant parkinsonism. MRI revealed abnormalities of the medulla and cervical spinal cord typical of adult-onset Alexander disease, and genetic testing showed homozygosity for the p.D295N polymorphic allele in the gene encoding the glial fibrillary acidic protein. A review of the literature shows that ocular signs are frequent in adult-onset Alexander disease, most commonly gaze-evoked nystagmus, pendular nystagmus, and/or oculopalatal myoclonus, and less commonly ptosis, miosis, and saccadic dysmetria. These signs are consistent with the propensity of adult-onset Alexander disease to cause medullary abnormalities on neuroimaging.

  9. Ocular diseases at geriatric clinics in Rio de Janeiro: social and epidemiological considerations among patients with motor locomotion deficit

    Directory of Open Access Journals (Sweden)

    Nadyr A. Damasceno

    2015-02-01

    Full Text Available Objective: To identify the causes of low visual acuity and systemic morbidities that limit ambulation and access to eye care in geriatric clinics in Rio de Janeiro. Methods: This cross-sectional study evaluated 187 patients from three geriatric clinics in Rio de Janeiro between January 2010 and January 2011. The inclusion criteria were individuals with a visual acuity of less than of equal to 20/200 in either eye (118 individuals, without optical correction. The exclusion criteria were individuals who refused to participate and those unable to undergo screening because of mental disabilities (6 individuals. Of the 187 individuals evaluated, 63 had visual acuity above 20/200. Results: A total of 118 individuals with a visual acuity of ≤20/200 effectively participated in the study after meeting the inclusion and exclusion criteria. In addition, 57 participants (48.3% presented systemic disabling morbidities. Of the 118 individuals with low visual acuity, 27.96% had cataract and 26.27% had refractive errors. Conclusion: Most of the patients from geriatric clinics experienced ocular morbidities, but their proper treatment resulted in improved visual acuity. A more socially oriented problem associated with eye care involved the difficulty of access to ophthalmologic consultations.

  10. Randomized controlled comparative study on effect of training to improve lower limb motor paralysis in convalescent patients with post-stroke hemiplegia

    National Research Council Canada - National Science Library

    Kawakami, Kenji; Miyasaka, Hiroyuki; Nonoyama, Sayaka; Hayashi, Kazuya; Tonogai, Yusuke; Tanino, Genichi; Wada, Yosuke; Narukawa, Akihisa; Okuyama, Yuko; Tomita, Yutaka; Sonoda, Shigeru

    2015-01-01

    [Purpose] The motor paralysis-improving effect on the hemiplegic lower limb was compared among mirror therapy, integrated volitional-control electrical stimulation, therapeutic electrical stimulation...

  11. Randomized controlled comparative study on effect of training to improve lower limb motor paralysis in convalescent patients with post-stroke hemiplegia

    National Research Council Canada - National Science Library

    KENJI KAWAKAMI; HIROYUKI MIYASAKA; SAYAKA NONOYAMA; KAZUYA HAYASHI; YUSUKE TONOGAI; GENICHI TANINO; YOSUKE WADA; AKIHISA NARUKAWA; YUKO OKUYAMA; YUTAKA TOMITA; SHIGERU SONODA

    2015-01-01

    [Abstract.] [Purpose] The motor paralysis-improving effect on the hemiplegic lower limb was compared among mirror therapy, integrated volitional-control electrical stimulation, therapeutic electrical stimulation...

  12. Development and initial validation of the volition in exercise questionnaire (VEQ)

    DEFF Research Database (Denmark)

    Elsborg, Peter; Wikman, Johan Michael; Nielsen, Glen

    2017-01-01

    structure was developed in an exploratory factor analysis which resulted in a reliable structure of the following six factors: Volitional Inhibition — Reasons, Volitional Inhibition — Postponing Training, Volitional Facilitation — Self-Confidence, Volitional Inhibition — Unrelated Thoughts, Volitional...... Inhibition — Approval From Others, and Volitional Facilitation — Coping with Failure. A sound theoretical explanation for these six factors is based on the Personal System Interaction Theory. This six-factor structure was also confirmed in a new sample in a confirmatory factor analysis, delivering an 18-item...

  13. Development and Initial Validation of the Volition in Exercise Questionnaire (VEQ)

    DEFF Research Database (Denmark)

    Elsborg, P.; Wikman, J. M.; Nielsen, G.

    2017-01-01

    structure was developed in an exploratory factor analysis which resulted in a reliable structure of the following six factors: Volitional Inhibition—Reasons, Volitional Inhibition—Postponing Training, Volitional Facilitation—Self-Confidence, Volitional Inhibition—Unrelated Thoughts, Volitional Inhibition......—Approval From Others, and Volitional Facilitation—Coping with Failure. A sound theoretical explanation for these six factors is based on the Personal System Interaction Theory. This six-factor structure was also confirmed in a new sample in a confirmatory factor analysis, delivering an 18-item questionnaire...

  14. Positive or negative feedback of optokinetic signals: degree of the misrouted optic flow determines system dynamics of human ocular motor behavior.

    Science.gov (United States)

    Chen, Chien-Cheng; Bockisch, Christopher J; Olasagasti, Itsaso; Weber, Konrad P; Straumann, Dominik; Huang, Melody Ying-Yu

    2014-04-09

    The optokinetic system in healthy humans is a negative-feedback system that stabilizes gaze: slow-phase eye movements (i.e., the output signal) minimize retinal slip (i.e., the error signal). A positive-feedback optokinetic system may exist due to the misrouting of optic fibers. Previous studies have shown that, in a zebrafish mutant with a high degree of the misrouting, the optokinetic response (OKR) is reversed. As a result, slow-phase eye movements amplify retinal slip, forming a positive-feedback optokinetic loop. The positive-feedback optokinetic system cannot stabilize gaze, thus leading to spontaneous eye oscillations (SEOs). Because the misrouting in human patients (e.g., with a condition of albinism or achiasmia) is partial, both positive- and negative-feedback loops co-exist. How this co-existence affects human ocular motor behavior remains unclear. We presented a visual environment consisting of two stimuli in different parts of the visual field to healthy subjects. One mimicked positive-feedback optokinetic signals and the other preserved negative-feedback optokinetic signals. By changing the ratio and position of the visual field of these visual stimuli, various optic nerve misrouting patterns were simulated. Eye-movement responses to stationary and moving stimuli were measured and compared with computer simulations. The SEOs were correlated with the magnitude of the virtual positive-feedback optokinetic effect. We found a correlation among the simulated misrouting, the corresponding OKR, and the SEOs in humans. The proportion of the simulated misrouting needed to be greater than 50% to reverse the OKR and at least greater than or equal to 70% to evoke SEOs. Once the SEOs were evoked, the magnitude positively correlated to the strength of the positive-feedback OKR. This study provides a mechanism of how the misrouting of optic fibers in humans could lead to SEOs, offering a possible explanation for a subtype of infantile nystagmus syndrome (INS).

  15. EMOTIONAL AND VOLITIONAL RELIABILITY AS A SUBJECT OF SCIENTIFIC ANALYSIS

    Directory of Open Access Journals (Sweden)

    Xia Juan

    2016-11-01

    Full Text Available The article analyses the scientists’ views on the phenomenon of “reliability”. The author pays special attention to the fact that the concept “reliability” is considered by the scientists as the systematic characteristic, which is characterized by the specific number of professional, psychological, physiological qualities and functions at the different levels of a person’s activity. This activity provides stable and reliable work. It is found out that scientists think the quality is the most important property which provides definiteness to any phenomenon. Personal qualities that affect the maturity of emotional and volitional reliability are established. Scientific interpretation of the concept of “reliability” and the main features of performing reliability is revealed. The analysis of pedagogical and psychological literature proves that the emotional qualities are being formed throughout the life according to the person’s environmental and genetic conditions. Emotional irritability, emotional stability, emotional tone, emotional reactions, emotional stability are the qualities which depend upon a type of a person’s higher nervous activity. The person’s activity, especially music one, can’t exist without involving emotions and feelings. Music plays an important role; due to it emotions become conscious processes. Thanks to music the person’s higher emotions (moral, intellectual, esthetic are formed. It is noticed that individual differences in demonstration of emotions depend on a person’s volitional qualities. Volition is considered to be a person’s psychological activity that determines purposefulness of actions. The author concluded that the maturity level of emotional and volitional reliability depends on direction and resistance of socially significant motives (needs, interests, values, attitudes; personality’s psychophysical traits (abilities, capacities, which provide the required level and effectiveness

  16. Ocular Sarcoidosis

    Science.gov (United States)

    Pasadhika, Sirichai; Rosenbaum, James T

    2015-01-01

    Sarcoidosis is one of the leading causes of inflammatory eye disease. Ocular sarcoidosis can involve any part of the eye and its adnexal tissues, and may cause uveitis, episcleritis/scleritis, eyelid abnormalities, conjunctival granuloma, optic neuropathy, lacrimal gland enlargement and orbital inflammation. Glaucoma and cataract can be complications from inflammation itself or adverse effects from therapy. Ophthalmic manifestations can be isolated, or associated with other organ involvement. Patients with ocular sarcoidosis can present with a wide range of clinical presentations and severity. Multi-disciplinary approaches are required to achieve the best treatment outcomes for both ocular and systemic manifestations. PMID:26593141

  17. Traumatismos oculares Ocular traumas

    Directory of Open Access Journals (Sweden)

    Gelen Welch Ruiz

    2007-12-01

    Full Text Available Se realizó un estudio descriptivo de tipo retrospectivo longitudinal cuyo universo estuvo constituido por 72 ojos de 72 pacientes con traumatismos oculares mecánicos que fueron hospitalizados en el Hospital Militar Central “Dr. Carlos J. Finlay” desde enero de 1999 hasta enero de 2005. Para el análisis estadístico de la información se utilizó el programa automatizado SPSS versión 11.5 en el cual también se conformó la base de datos y se realizaron los cálculos de acuerdo con el tipo de variable analizada. Se utilizaron medidas de resumen, tendencia central y asociación estadística con un nivel de significación de p A retrospective longitudinal and descriptive study was carried out in 72 eyes from 72 patients with mechanical occular traumas, who had been hospitalized in “Dr. Carlos J. Finlay” Military Hospital from December 1999 to January 2005. For the statistical data analysis, an automated program (SPSS 11.5 version was used to create the database and estimations were made according to the variable types. Summary measures, central tendency measures and statistical association with significance level equal to p < 0.05 were employed. Males prevailed (95.8%, the average age was 30.26 years with a minimum rate of 17 years and maximum rate of 82 years. The most frequent mechanisms of trauma were aggressions (23. 6% and injures from secondary projectiles (13.9%. The anterior segment traumas were more frequent (61, 1% than posterior segment traumas (6.94%. Both segments of the eyeball were affected in 39, 1% of eyes which evinced the worst visual acuity. The most common associated injures were hyphema (54, 2% and vitreous hemorrhage (16.6%. Closed trauma (contusions were more common and most of the eyes had better final visual acuity (45, 2% with vision range of 0.6-1.0 and 26.2% with vision range of 0.59-0.1. On the other hand, eyes affected by open trauma (simple wound, contusion-wound, wound with intraocular foreign body and

  18. Ocular Injury

    Science.gov (United States)

    ... Conditions Frequently Asked Questions Español Condiciones Chinese Conditions Ocular Injury En Español What causes eye injuries ? Injuries ... only the eyelid but the structures that drain tears from the eye. Lacerations of the eyelid or ...

  19. Ocular Rosacea

    Science.gov (United States)

    ... default.asp. Accessed March 31, 2015. Bron A. Ocular rosacea. http://www.uptodate.com. Accessed March 31, 2015. Riordan-Eva P, et al. Conjunctiva and tears. In: Vaughan & Asbury's General Ophthalmology. 18th ed. New ...

  20. Ocular rosacea

    Directory of Open Access Journals (Sweden)

    Đaković Zorana

    2004-01-01

    Full Text Available Five cases of ocular rosacea (one male and four females are reported in this paper. Two of the patients were with keratoconjunctivitis sicca, one with conjunctivitis chronica and blepharitis, one with conjunctivitis chronica and meibomitis, and one with reccurent corneal erosions with meibomitis and chordeloum. In four patients ocular symptoms preceded the occurence of skin lesions. The treatment with oral tetracyclines significantly improved the state of ocular rosacea in four patients, while in one case the changes of the anterior eye segment progressed in more severe state of ulcerative keratitis. It is considered that in almost 20% of the patients with rosacea ocular lesions may precede the skin changes, representing a diagnostic problem. Thus, in those cases multidisciplinary approach is suggested. Such approach is particularly important because of the decrease of morbidity and the prevention of the onset of the eye complications such as drastic worsening of visual acuity, i.e., the blindness.

  1. VOLITIONAL STRATEGIES THROUGH METACOGNITIVE DEVELOPMENT IN FOSTERING READING MOTIVATION

    Directory of Open Access Journals (Sweden)

    Vismaia S. Damaianti

    2017-09-01

    Full Text Available Student’s reading skill is deemed vitally important to attain high academic achievements. The results of the previous studies, however, show that Indonesian students' reading skill is still unsatisfying due to their low motivation. The purpose of this study is to address this problem of students’ motivation by examining the effectiveness of a volitional strategy through metacognitive development to students of Islamic Junior High School [Madrasah Tsanawiyah] in Indonesia. A quasi-experimental method with a factorial design is used in this research. Indicators for increasing students’ reading motivation come from Cambria and Guthrie (2010. Measures of increased motivation to read with the volitional strategy were done through metacognitive development which is based on self-monitoring and awareness of reading skills mastery. This study concludes that the volitional strategy through metacognitive development is proved effective in increasing students’ motivation for reading, students with both low and high reading skills. This has implications for the efforts to foster motivation for reading by intensively using the strategy for Madrasah Tsanawiyah education contexts.

  2. Volition and low back pain: When patients talk.

    Science.gov (United States)

    Mathy, C; Cedraschi, C; Broonen, J-P; Azzi, A; Henrotin, Y

    2015-12-01

    Our objective was to explore, describe and understand volition of chronic low back pain (LBP) patients, highlighting barriers and facilitators to practicing regular physical activity in order to develop a questionnaire assessing those volitional competencies. A content analysis of semi-structured interviews with 30 chronic LBP patients was performed. Participants were asked about their pain, motivation, physical abilities, barriers and facilitators to regular exercises and finally strategies implemented to achieve the exercise program. Patients often reported that they were motivated and that exercises had no negative effects on LBP. Many patients recognized having difficulties performing all their exercises regularly. The main barriers were: lack of time, fatigue, lack of visible results, pain and other daily priorities. The main facilitators were: group exercise, help from the therapist, strategic planning, favorable environment, pleasure associated with exercises, fear of pain recurrence and pain itself. Content analysis showed that sharing stories allowed patients to express their experience of LBP in their own words. It provides a solid ground to develop a questionnaire assessing volitional competencies in chronic LBP patients in order to identify patients who will not realize their exercises and help them be (more) active and avoid chronicity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. Imaging volition: what the brain can tell us about the will.

    Science.gov (United States)

    Brass, Marcel; Lynn, Margaret T; Demanet, Jelle; Rigoni, Davide

    2013-09-01

    The question of how we can voluntarily control our behaviour dates back to the beginnings of scientific psychology. Currently, there are two empirical research disciplines tackling human volition: cognitive neuroscience and social psychology. To date, there is little interaction between the two disciplines in terms of the investigation of human volition. The aim of the current article is to highlight recent brain imaging work on human volition and to relate social psychological concepts of volition to the functional neuroanatomy of intentional action. A host of studies indicate that the medial prefrontal cortex plays a crucial role in voluntary action. Accordingly, we postulate that social psychological concepts of volition can be investigated using neuroimaging techniques, and propose that by developing a social cognitive neuroscience of human volition, we may gain a deeper understanding of this fascinating and complex aspect of the human mind.

  4. Ocular Straylight

    Directory of Open Access Journals (Sweden)

    Sigrid Mueller-Schotte OD, MSc

    2015-10-01

    Full Text Available Intra-ocular straylight can cause decreased visual functioning, and it may cause diminished vision-related quality of life (VRQOL. This cross-sectional population-based study investigates the association between straylight and VRQOL in middle-aged and elderly individuals. Multivariable linear regression analyses were used to assess the association between straylight modeled continuously and cutoff at the recommended fitness-to-drive value, straylight ≥ 1.4 log(s, and VRQOL. The study showed that participants with normal straylight values, straylight ≤ 1.4 log(s, rated their VRQOL slightly better than those with high straylight values (straylight ≥ 1.4 log(s. Furthermore, multivariable regression analysis revealed a borderline statistical significant association ( p = .06 between intra-ocular straylight and self-reported VRQOL in middle-aged and elderly individuals. The association between straylight and self-reported VRQOL was not influenced by the status of the intra-ocular lens (natural vs. artificial intra-ocular lens after cataract extraction or the number of (instrumental activities of daily living that were reported as difficult for the elderly individuals.

  5. Ocular Straylight

    Science.gov (United States)

    Mueller-Schotte, Sigrid; van der Schouw, Yvonne T.; Schuurmans, Marieke J.

    2015-01-01

    Intra-ocular straylight can cause decreased visual functioning, and it may cause diminished vision-related quality of life (VRQOL). This cross-sectional population-based study investigates the association between straylight and VRQOL in middle-aged and elderly individuals. Multivariable linear regression analyses were used to assess the association between straylight modeled continuously and cutoff at the recommended fitness-to-drive value, straylight ≥ 1.4 log(s), and VRQOL. The study showed that participants with normal straylight values, straylight ≤ 1.4 log(s), rated their VRQOL slightly better than those with high straylight values (straylight ≥ 1.4 log(s)). Furthermore, multivariable regression analysis revealed a borderline statistical significant association (p = .06) between intra-ocular straylight and self-reported VRQOL in middle-aged and elderly individuals. The association between straylight and self-reported VRQOL was not influenced by the status of the intra-ocular lens (natural vs. artificial intra-ocular lens after cataract extraction) or the number of (instrumental) activities of daily living that were reported as difficult for the elderly individuals. PMID:28138473

  6. Ocular toxicology.

    Science.gov (United States)

    Novack, G D

    1997-12-01

    This review of recent articles on ocular toxicology concentrates on undesirable effects on the eye induced by systemically used xenobiotics. These include color vision deficiencies or visual field deterioration related to antiepileptic drugs, elevated intraocular pressure associated with inhaled corticosteroids, retinal detachments associated with systemic corticosteroids, rifabutin-induced uveitis, cocaine-related retinal hemorrhagic lesions in utero, deferoxamine-related decreases in vision, ocular allergy to bovine-derived collagen, and a large case study of hydroxychloroquine retinotoxicity. Other publications reviewed include a controlled study showing that glucose levels do not seem to alter color vision, a report that intravenous methotrexate can reach clinically meaningful levels in the aqueous humor, and a study showing the effect of systemic pentoxifylline on ocular blood flow and diabetes. With respect to systemic effects of topical ocular medications, there was a case report of apparent systemic exposure to pilocarpine from an Ocusert (Alza Corp., Palo Alto, CA), generalized urticaria after a single application of 1% cyclopentolate, and asthma induced with topical ketorolac. Readers are reminded that no drug achieves ultimate efficacy or ultimate safety. Thus, the decision to employ a given therapy involves a physician's evaluation of its therapeutic index, that is, the ratio between efficacy and toxicity.

  7. Volitional components of consciousness vary across wakefulness, dreaming and lucid dreaming

    OpenAIRE

    Martin eDresler; Leandra eEibl; Christian FJ Fischer; Renate eWehrle; Spoormaker, Victor I.; Axel eSteiger; Michael eCzisch; Marcel ePawlowski

    2014-01-01

    Consciousness is a multifaceted concept; its different aspects vary across species, vigilance states, or health conditions. While basal aspects of consciousness like perceptions and emotions are present in many states and species, higher-order aspects like reflective or volitional capabilities seem to be most pronounced in awake humans. Here we assess the experience of volition across different states of consciousness: 10 frequent lucid dreamers rated different aspects of volition according t...

  8. The role of volition in distance education: An exploration of its capacities

    Directory of Open Access Journals (Sweden)

    Markus Deimann

    2010-03-01

    Full Text Available During the past two decades, volition, defined as the ability to stay task-focused and ward off distractions, has become of special relevance for educational research and practice. It describes how decreased motivation or negative emotions can be dealt with by applying action control strategies. However, despite its potential, an important area of education has neglected volitional considerations: distance education (DE. This seems paradoxical because by its very nature distance education requires a great deal of persistence and effort that is volitional. Consequently, the present paper introduces a conceptual framework built on volitional theories; it aims to augment traditional perspectives and to analyse major challenges to DE, such as dropout rates.The paper reports results from a longitudinal study (September 2007-July 2009 that was conducted to determine the factorial structure of the Volitional Persona Test (VPT, an online instrument to assess volitional competence, and to obtain detailed information on students’ volitional competence at a large DE university and at numerous traditional universities in German-speaking countries. It was demonstrated that the construct of volition can be subdivided into distinct factors, volitional self-efficacy, consequence control, emotion control, and meta-cognition, which may enable the development of support systems that are tailored to learners’ individual needs. Implications for future research are discussed.

  9. Volitional and Nonvolitional Responses to Hypnotic Suggestions: Predictors and Subjective Experience.

    Science.gov (United States)

    Mohl, John C; Schutkofsky, Meriel J

    2017-04-01

    This investigation combined the data from two studies that used modified scoring of the Harvard Group Scale of Hypnotic Susceptibility (Shor & Orne, 1962) to evaluate deliberate, volitional responses to suggestions. One study also employed subjective ratings of each item of the Harvard Scale, with comparisons of nonvolitional, volitional, and non-responses. Based on the assumption that participants would have marked volitional responses as positive responses using the traditional scale, the traditional scoring method was found to inflate mean hypnotic responsiveness by nearly one point. Two hypothesized correlates of hypnotic performance, rapport with the hypnotist and a phenomenological measure of hypnosis, increased significantly when volitional responses were taken into account. The way in which participants were recruited did not predict volitional responses, but individuals who reported deliberate responses to suggestions from the Harvard Scale were less likely to express willingness to participate in future studies. Some of the volitional responses to the items were rated as subjectively more real compared to no responses, though nonvolitional responses were rated as the most real compared with compliance responses and no responses for all items. More difficult items were more likely to be performed volitionally than easier items. It is suggested that future studies using hypnotic inventories account for volitional responses. The nature of deliberately produced responses should also be examined using qualitative and quantitative data, especially with respect to how a given suggestion may affect the execution of the volitional behavior.

  10. Contemplative Neuroscience as an Approach to Volitional Consciousness

    Science.gov (United States)

    Thompson, Evan

    This chapter presents a methodological approach to volitional consciousness for cognitive neuroscience based on studying the voluntary self-generation and self-regulation of mental states in meditation. Called contemplative neuroscience, this approach views attention, awareness, and emotion regulation as flexible and trainable skills, and works with experimental participants who have undergone training in contemplative practices designed to hone these skills. Drawing from research on the dynamical neural correlates of contemplative mental states and theories of large-scale neural coordination dynamics, I argue for the importance of global system causation in brain activity and present an "interventionist" approach to intentional causation.

  11. [Ocular burns].

    Science.gov (United States)

    Merle, H; Gérard, M; Schrage, N

    2008-09-01

    Ocular or thermal burns account for 7.7%-18% of ocular trauma. The majority of victims are young. The burns occur in the setting of accidents at work or in the home, or during a physical attack. Chemical burns by strong acids or bases are responsible for the most serious injuries. Associated with the destruction of limbal stem cells, they present as recurrent epithelial ulcerations, chronic stromal ulcers, deep stromal revascularization, conjunctival overlap, or even corneal perforation. The initial clinical exam is sometimes difficult to perform in the presence of burning symptoms. Nevertheless, it enables the physician to classify the injury, establish a prognosis, and most importantly, guide the therapeutic management. The Roper-Hall modification of the Hughes classification system is the most widely utilized, broken down into stages based on the size of the stromal opacity and the extent of possible limbal ischemia. This classification is now favorably supplemented by those proposed by Dua and Wagoner, which are based on the extent of the limbal stem cell deficiency. The prognosis of the more serious forms of ocular burns has markedly improved over the last decade because of a better understanding of the physiology of the corneal epithelium. Surgical techniques aimed at restoring the destroyed limbal stem cells have altered the prognosis of severe corneal burns. In order to decrease the incidence of burns, prevention, particularly in industry, is essential.

  12. Outdoor games - as a means education volitional qualities personality of athletes.

    Directory of Open Access Journals (Sweden)

    Chervona S.F.

    2011-02-01

    Full Text Available The usefulness of specialized mobile games in the upbringing of volitional qualities of the individual athletes. In experimental studies involved 152 students majors basketball, volleyball, handball, football. The results showed that the introduction of new elements into mobile games, contribute to the appearance, education, consolidation of volitional qualities of athletes.

  13. Work Volition as a Critical Moderator in the Prediction of Job Satisfaction

    Science.gov (United States)

    Duffy, Ryan D.; Bott, Elizabeth M.; Torrey, Carrie L.; Webster, Gregory W.

    2013-01-01

    Building on the Psychology of Working Framework, the current study explored the extent to which work volition functioned as a moderator in the relation between positive affect, core self-evaluations, perceived organizational support (POS), and work self-efficacy to job satisfaction. In a diverse sample of 206 employed adults, work volition was…

  14. Work Volition, Career Decision Self-Efficacy, and Academic Satisfaction: An Examination of Mediators and Moderators

    Science.gov (United States)

    Jadidian, Alex; Duffy, Ryan D.

    2012-01-01

    The present study examined the relation of work volition to career decision self-efficacy (CDSE) and academic satisfaction in a diverse sample of 447 undergraduate college students. Work volition was found to be moderately correlated with academic satisfaction and strongly correlated with CDSE. Potential mediators and moderators in the link of…

  15. Cisticercosis ocular

    Directory of Open Access Journals (Sweden)

    Danaides Arencibia González

    Full Text Available La cisticercosis establece un grupo de enfermedades zoonóticas parasitarias; cuando se aloja en el ojo y sus anexos producen una cisticercosis ocular y periocular. Constituye una de las causas de uveítis ocular y pérdida importante de la visión. El diagnóstico clínico se realiza mediante la observación directa del parásito, cuando existen opacidades de los medios, el ultrasonido se emplea como medio diagnóstico útil. Los anti helmintos asociados a esteroides forman parte de su terapéutica, sumado al tratamiento definitivo de la extracción del parásito, en este tipo de afección mediante vitrectomía vía pars plana. Se presenta un caso portador de esta condición, se describen las características más importantes del cuadro clínico, diagnóstico, manejo y curso evolutivo-terapéutico.

  16. Cognitive Neurostimulation: Learning to Volitionally Sustain Ventral Tegmental Area Activation

    Science.gov (United States)

    MacInnes, Jeff J.; Dickerson, Kathryn C.; Chen, Nan-kuei; Adcock, R. Alison

    2016-01-01

    SUMMARY Activation of the ventral tegmental area (VTA) and mesolimbic networks is essential to motivation, performance, and learning. Humans routinely attempt to motivate themselves, with unclear efficacy or impact on VTA networks. Using fMRI, we found untrained participants’ motivational strategies failed to consistently activate VTA. After real-time VTA neurofeedback training, however, participants volitionally induced VTA activation without external aids, relative to baseline, Pre-Test, and control groups. VTA self-activation was accompanied by increased mesolimbic network connectivity. Among two comparison groups (no neurofeedback, false neurofeedback) and an alternate neurofeedback group (nucleus accumbens), none sustained activation in target regions of interest nor increased VTA functional connectivity. The results comprise two novel demonstrations: learning and generalization after VTA neurofeedback training and the ability to sustain VTA activation without external reward or reward cues. These findings suggest theoretical alignment of ideas about motivation and midbrain physiology and the potential for generalizable interventions to improve performance and learning. PMID:26948894

  17. Intention recognition for FES in a grasp-and-release task using volitional EMG and inertial sensors

    Directory of Open Access Journals (Sweden)

    Salchow Christina

    2017-09-01

    Full Text Available Functional Electrical Stimulation (FES facilitates the motor recovery of the hand function after stroke. The integration of biofeedback and other strategies to actively in-volve a patient in the therapy is important for the rehabili-tation progress. We introduce a combined control approach for a FES-driven neuroprosthesis using volitional electromyo-graphy (vEMG and motion capturing via a novel inertial sensor network for patients that still possess a residual activity in the paralyzed muscles. A real-time vEMG measurement and signal processing in between stimulation pulses has been realized during active FES. Experiments showed that our system allows for quick adaption to individual users.

  18. Pediatric ocular emergencies.

    Science.gov (United States)

    Hamilton, H L

    1999-07-01

    There are few ocular emergencies that are unique to the pediatric patient. Most ocular emergencies are traumatic in origin, and the prognosis is often determined by the extent of the injury. Some congenital anomalies that may present as ocular emergencies are also discussed. The focus of this article is recognition and initial therapy for the more common pediatric ocular emergencies.

  19. Airbag related ocular injuries: a short case series | Onakoya ...

    African Journals Online (AJOL)

    Airbags are designed to protect occupants of motor vehicles from injuries in the event of a crash but have been implicated in some serious ocular injuries after road traffic accidents (RTAs). Diagnosis of airbag related ocular injuries requires a high index of suspicion. Using a retrospective hospital‑based, noninterventional ...

  20. The relationship between physical activity, volitional skills and weight loss maintenance in Danish obese individuals

    DEFF Research Database (Denmark)

    Elsborg, Peter; Pfister, Gertrud Ursula; Helge, Jørn Wulff

    course are discussed. Conflict of Interest: None to declare. Funding The study is supported by the research programme "Physical activity and nutrition for improvement of health" funded by the University of Copenhagen Excellence Programme for Interdisciplinary Research....... volitional skills. Conclusion: This study indicates that volitional skills seem to be an important component in the difficult task of weight maintenance. Implications for future research with a large sample of 2000 former participants and practical implications for the design of the life style intervention...

  1. The influence of oxytocin on volitional and emotional ambivalence

    Science.gov (United States)

    Preckel, Katrin; Eckstein, Monika; Maier, Wolfgang; Hurlemann, René

    2015-01-01

    Moral decisions and social relationships are often characterized by strong feelings of ambivalence which can be a catalyst for emotional distress and several health-related problems. The anterior cingulate cortex (ACC) has been identified as a key brain region in monitoring conflicting information, but the neurobiological substrates of ambivalence processing are still widely unknown. We have conducted two randomized, double-blind, placebo-controlled, functional magnetic resonance imaging experiments involving 70 healthy male volunteers to investigate the effects of the neuropeptide oxytocin (OXT) on neural and behavioral correlates of ambivalence. We chose moral decision-making and the imagery of partner infidelity as examples to probe volitional and emotional ambivalence. In both experiments, intranasal OXT diminished neural responses in the ACC to ambivalence. Under OXT, moral dilemma vignettes also elicited a reduced activation in the orbitofrontal cortex, and the imagery of partner infidelity was rated as less arousing. Interestingly, the OXT-induced differential activation in the ACC predicted the magnitude of arousal reduction. Taken together, our findings reveal an unprecedented role of OXT in causing a domain-general decrease of neural responses to ambivalence. By alleviating emotional distress, OXT may qualify as a treatment option for psychiatric disorders with heightened ambivalence sensitivity such as schizophrenia or obsessive-compulsive disorder. PMID:25398434

  2. Response selection in prosaccades, antisaccades, and other volitional saccades.

    Science.gov (United States)

    Kloft, Lisa; Reuter, Benedikt; Viswanathan, Jayalakshmi; Kathmann, Norbert; Barton, Jason J S

    2012-10-01

    Saccades made to the opposite side of a visual stimulus (antisaccades) and to central cues (simple volitional saccades) both require active response selection but whether the mechanisms of response selection differ between these tasks is unclear. Response selection can be assessed by increasing the number of response alternatives: this leads to increased reaction times when response selection is more demanding. We compared the reaction times of prosaccades, antisaccades, saccades cued by a central arrow, and saccades cued by a central number, in blocks of either two or six possible responses. In the two-response blocks, reaction times were fastest for prosaccades and antisaccades, and slowest for arrow-cued and number-cued saccades. Increasing response alternatives from two to six caused a paradoxical reduction in reaction times of prosaccades, had no effect on arrow-cued saccades, and led to a large increase in reaction times of number-cued saccades. For antisaccade reaction times, the effect of increasing response alternatives was intermediate, greater than that for arrow-cued saccades but less than that for number-cued saccades. We suggest that this pattern of results may reflect two components of saccadic processing: (a) response triggering, which is more rapid with a peripheral stimulus as in the prosaccade and antisaccade tasks and (b) response selection, which is more demanding for the antisaccade and number-cued saccade tasks, and more automatic when there is direct stimulus-response mapping as with prosaccades, or over-learned symbols as with arrow-cued saccades.

  3. Short duration exhaustive aerobic exercise induces oxidative stress: a novel play-oriented volitional fatigue test.

    Science.gov (United States)

    Kyparos, A; Salonikidis, K; Nikolaidis, M G; Kouretas, D

    2007-12-01

    Exercise is associated with the generation of reactive oxygen and nitrogen species. This study examined the oxidative stress in response to a novel volitional fatigue test. Eleven male college students performed a volitional fatigue test consisting of shuttle runs with a tennis racquet in the hand towards the left and right sidelines within the tennis singles court in an attempt to hit tennis balls until exhaustion. A tennis ball serving machine was adjusted to alternate feeds to the forehand and backhand sides of the subjects, standing at the baseline, at a frequency of 20 balls per minute. Mean time to volitional fatigue was 5.9+/-1.3 min and mean heart rate at volitional fatigue was 189+/-8.1 beats x min(-1). The volitional fatigue test resulted in significant increases in blood thiobarbituric acid-reactive substances (22%), protein carbonyls (58%), catalase activity (143%), total antioxidant capacity (34%) and oxidized glutathione (GSSG, 81%) concentration, as well as significant decreases in reduced glutathione (GSH, 15%) concentration and GSH/GSSG ratio (56%) immediately postexercise, as compared to the pre-exercise concentration. The data provide evidence that acute short duration exhaustive aerobic exercise in the form of a novel volitional fatigue test is capable of inducing oxidative stress. This novel test could serve as an alternative exercise modality to study oxidative stress.

  4. Relationship of Reaction Time to Perception of a Stimulus and Volitionally Delayed Response.

    Science.gov (United States)

    Meador, Kimford J; Boyd, Alan; Loring, David W

    2017-06-01

    Initiation of response in a simple reaction time (RT) task may precede conscious perception of the stimulus. Since volitionally delayed responses may require conscious perception of the stimulus before response initiation, it has been hypothesized that volitionally delayed responses will markedly delay RT. We conducted two experiments with separate groups of healthy volunteers (n=16; n=13) who performed computerized simple and choice RT tasks. In the standard condition, we instructed the participants to respond to a visual stimulus by pushing a button as quickly as possible. In the second condition, we instructed the participants to respond after a slight volitional delay. The second experiment had an additional volitional delay condition in which we asked participants to delay their responses by an estimated 50% above their usual standard response. We found marked delays and increased variability when participants volitionally delayed their responses, averaging 322 ms for standard and 861 ms for delayed simple RTs (267% increase), and 650 ms for standard and 1018 ms for delayed choice RTs (157% increase). Effects did not differ across age, sex, or handedness. However, a minority of participants did not meaningfully delay their RT during the volitional delay conditions. On average, participants had marked delays when they tried to delay their responses slightly, but a subset of participants exhibited essentially no delay despite trying to delay. We suggest some potential mechanisms that future investigations might delineate.

  5. Do the clinical features in infantile-onset saccade initiation delay (congenital ocular motor apraxia) correlate with brain magnetic resonance imaging findings?

    Science.gov (United States)

    Salman, Michael S; Ikeda, Kristin M

    2014-09-01

    Infantile-onset saccade initiation delay (ISID) is a defect in saccade initiation. Other features may include impaired smooth ocular pursuit, developmental delay, hypotonia, and ataxia. Brain magnetic resonance imaging (MRI) can be normal or show supratentorial or infratentorial abnormalities. Our aim was to correlate the clinical features of ISID with brain MRI findings. Detailed review of the English medical literature between 1952 and 2012 revealed 67 studies with possible ISID. Patients without a brain MRI or with inadequate information, Joubert syndrome, neurodegenerative disorders, and acquired saccade initiation delay were excluded. Ninety-one patients (age range, 3 months to 45 years) met the inclusion criteria and were divided into 3 groups based on their brain MRI findings: normal (n = 55), supratentorial abnormalities (n = 17), and infratentorial abnormalities (n = 19). The patients' clinical features including the direction of head thrusts, smooth pursuit, optokinetic response (OKR), tone, development, and coordination were compared and analyzed among the MRI groups using χ test. Horizontal head thrusts were significantly more common in patients with infratentorial abnormalities or normal brain MRI, whereas vertical head thrusts were more common among patients with supratentorial abnormalities (P < 0.0001). The slow phases of the OKR were significantly more likely to be impaired in patients with supratentorial or infratentorial abnormalities than in those with a normal MRI (P = 0.011). Other neuro-ophthalmological, neurological, and developmental features were similar among patients in the 3 neuroimaging groups. The direction of head thrust and the integrity of the slow phases of the OKR are useful clinical indicators of possible sites of abnormality on brain MRI in patients with ISID.

  6. Volition-adaptive control for gait training using wearable exoskeleton: preliminary tests with incomplete spinal cord injury individuals.

    Science.gov (United States)

    Rajasekaran, Vijaykumar; López-Larraz, Eduardo; Trincado-Alonso, Fernando; Aranda, Joan; Montesano, Luis; Del-Ama, Antonio J; Pons, Jose L

    2018-01-03

    Gait training for individuals with neurological disorders is challenging in providing the suitable assistance and more adaptive behaviour towards user needs. The user specific adaptation can be defined based on the user interaction with the orthosis and by monitoring the user intentions. In this paper, an adaptive control model, commanded by the user intention, is evaluated using a lower limb exoskeleton with incomplete spinal cord injury individuals (SCI). A user intention based adaptive control model has been developed and evaluated with 4 incomplete SCI individuals across 3 sessions of training per individual. The adaptive control model modifies the joint impedance properties of the exoskeleton as a function of the human-orthosis interaction torques and the joint trajectory evolution along the gait sequence, in real time. The volitional input of the user is identified by monitoring the neural signals, pertaining to the user's motor activity. These volitional inputs are used as a trigger to initiate the gait movement, allowing the user to control the initialization of the exoskeleton movement, independently. A Finite-state machine based control model is used in this set-up which helps in combining the volitional orders with the gait adaptation. The exoskeleton demonstrated an adaptive assistance depending on the patients' performance without guiding them to follow an imposed trajectory. The exoskeleton initiated the trajectory based on the user intention command received from the brain machine interface, demonstrating it as a reliable trigger. The exoskeleton maintained the equilibrium by providing suitable assistance throughout the experiments. A progressive change in the maximum flexion of the knee joint was observed at the end of each session which shows improvement in the patient performance. Results of the adaptive impedance were evaluated by comparing with the application of a constant impedance value. Participants reported that the movement of the

  7. OCULAR MANIFESTATIONS OF HEAD INJURIES

    Directory of Open Access Journals (Sweden)

    Kanukollu Venkata Madusudana Rao

    2016-12-01

    Full Text Available BACKGROUND This prospective study aimed to evaluate the incidence of ocular manifestations in head injury and their correlation with the intracranial lesions. MATERIALS AND METHODS A total of 108 consecutive cases of closed head injury admitted in the neurosurgical ward of a tertiary teaching hospital underwent a thorough ophthalmic assessment. Clinical examination, radiological imaging and Glasgow Coma Scale (GCS were applied to grade the severity of injury. RESULTS Total number of 108 patients of head injury were examined of which 38 patients had ocular manifestations (35.18%. Of these, 85.18% were males, 84% of injuries were due to road traffic accidents and 16% were due to fall from a height. The ocular manifestations were as follows- Orbital complications were seen in 6 patients (15.8%. Anterior segment manifestations included black eyes seen in 10 patients (26.3%, subconjunctival haemorrhage in 10.5% of patients (4 patients, corneal involvement in 21% of patients (8 patients and pupillary involvement in 50% of patients (19 patients. Posterior segment manifestations were seen in 26.3% of patients (10 patients and were as follows- Purtscher’s retinopathy in 2 patients and optic atrophy in 5 patients. Cranial nerve palsies were seen in 15 patients (39.47% and supranuclear movement disorders were seen in 3 patients (8%. CONCLUSION Even though, neurosurgeons perform comprehensive clinical examination including eye examination, the main purpose is limited to aid topical diagnosis of neurological lesions. This study emphasises the importance of a detailed eye examination by an ophthalmologist to prevent irreversible visual loss in addition to aiding in the neurological diagnosis. Pupillary involvement, papilloedema and ocular motor paresis pointed to a more severe head injury. This observational prospective study helped us to correlate the severity of head injuries in association with ocular findings in patients admitted in neurosurgical ward

  8. Ocular Paintball Injuries

    National Research Council Canada - National Science Library

    Nemet, Arie Y; Asalee, Leena; Lang, Yaron; Briscoe, Daniel; Assia, Ehud I

    2016-01-01

    Background: One of the most alarming ocular injury trends in recent years has been the proliferation of paintball guns and the proportional increase in the number of ocular eye injuries caused by paintballs...

  9. Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface

    Directory of Open Access Journals (Sweden)

    Yoshio eSakurai

    2014-02-01

    Full Text Available In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain–machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain–machine interface (BMI. We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them.

  10. Volitional enhancement of firing synchrony and oscillation by neuronal operant conditioning: interaction with neurorehabilitation and brain-machine interface.

    Science.gov (United States)

    Sakurai, Yoshio; Song, Kichan; Tachibana, Shota; Takahashi, Susumu

    2014-01-01

    In this review, we focus on neuronal operant conditioning in which increments in neuronal activities are directly rewarded without behaviors. We discuss the potential of this approach to elucidate neuronal plasticity for enhancing specific brain functions and its interaction with the progress in neurorehabilitation and brain-machine interfaces. The key to-be-conditioned activities that this paper emphasizes are synchronous and oscillatory firings of multiple neurons that reflect activities of cell assemblies. First, we introduce certain well-known studies on neuronal operant conditioning in which conditioned enhancements of neuronal firing were reported in animals and humans. These studies demonstrated the feasibility of volitional control over neuronal activity. Second, we refer to the recent studies on operant conditioning of synchrony and oscillation of neuronal activities. In particular, we introduce a recent study showing volitional enhancement of oscillatory activity in monkey motor cortex and our study showing selective enhancement of firing synchrony of neighboring neurons in rat hippocampus. Third, we discuss the reasons for emphasizing firing synchrony and oscillation in neuronal operant conditioning, the main reason being that they reflect the activities of cell assemblies, which have been suggested to be basic neuronal codes representing information in the brain. Finally, we discuss the interaction of neuronal operant conditioning with neurorehabilitation and brain-machine interface (BMI). We argue that synchrony and oscillation of neuronal firing are the key activities required for developing both reliable neurorehabilitation and high-performance BMI. Further, we conclude that research of neuronal operant conditioning, neurorehabilitation, BMI, and system neuroscience will produce findings applicable to these interrelated fields, and neuronal synchrony and oscillation can be a common important bridge among all of them.

  11. Stress-stimulated volitional coping competencies and depression in multiple sclerosis.

    Science.gov (United States)

    Nielsen-Prohl, J; Saliger, J; Güldenberg, V; Breier, G; Karbe, H

    2013-03-01

    The present study examined the relationship between volitional modes of coping (self-regulation, volitional inhibition, and self-control) and depression in individuals with multiple sclerosis. A cross-sectional study of 121 participants aged 22-60 years with clinically defined MS who were consecutively admitted to a neurological rehabilitation center during a 23-month period. Correlation analyses and hierarchical regressions were conducted to evaluate the predictive value of volitional competencies (Volitional Components Questionnaire, short form, VCQ-S) on depression (Centre for Epidemiologic Studies Depression Scale, CES-D), while controlling for demographic (age, gender, and education) and certain clinical variables (Expanded Disability Status Scale, EDSS; disease duration; and Modified Fatigue Impact Scale, MFIS). Hierarchical regression analyses of depression revealed a model in which 68% of the variance in the CES-D was explained by daily stress situations (VCQ-S), self-regulation (VCQ-S), fatigue (MFIS), and education. However, when the analysis included only participants who had scored above the cut-off of the CES-D (n=42), the VCQ-S factor volitional inhibition seemed to play a more relevant part in depression. In particular, the VCQ-S scales stimulation of self-access, stimulation of volitional inhibition, self-motivation, and emotional perseverance/state orientation after failure appear to be valuable predictors on CES-D. The results suggest that personality-accentuated volitional coping competencies elicited by daily stressful situations could be a relevant factor for depressive mood states in individuals with MS. However, to clarify the exact relationships of this rather circular framework, longitudinal study designs with objective measurements and a stronger focus on MS-specific stressors are needed. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. The perception of mothers about the volition of children with cerebral palsy for the engagement in everyday life occupations

    Directory of Open Access Journals (Sweden)

    Alyne Kalyane Câmara de Oliveira

    2014-04-01

    Full Text Available Volition, as the willingness to engage/performing daily activities, is considered a prerequisite of human doing. In children with special needs such as cerebral palsy (CP who deal with deficits of sensorimotor control and musculoskeletal, the volition can work as an influential feature to their engagement in occupations. The family is an important mediator in the child´s volitional process. However, researches about influence of the volition of children with special needs are scarce. This study aimed to identify how mothers perceive and deal with the volition of the child with CP to perform daily activities in scholar, play and self-care areas. Participated six mothers of children with CP, between 6 and 9 years old, levels I and IV of the GMFCS in a school -health unit inside Paulista, who answered a semistructured interview based on The Volitional Questionnaire. Based on the analysis of the content, three topics emerged: a mother’s perceptions about the volition of children; b mothers’ perception regarding their role in the child´s volitional process and c strategies used by mothers to encourage children to develop volition. Results showed that mothers perceive the relationship of the child volition versus involvement in activities and their importance in child´s volition for activities who judge relevant, mainly the formal school activities and self-care, with slightest consideration for the play. These mothers are looking for ways to implement the incentive, but they have revealed limited knowledge about strategies for stimulation of volition, showing the need for investments in health education for the guidance of those families.

  13. Eye Position Feedback in a Model of the Vestibulo-Ocular Reflex for Spino-Cerebellar Ataxia 6

    National Research Council Canada - National Science Library

    Anderson, J

    2001-01-01

    ..., incoordination, ocular motor dysfunction, and dysarthria due to degeneration of cerebellar and brainstem neurons. Recent studies have established that there are more than 16 genetically distinct subtypes...

  14. Repeated exercise stress impairs volitional but not magnetically evoked electromechanical delay of the knee flexors.

    Science.gov (United States)

    Minshull, Claire; Eston, Roger; Bailey, Andrea; Rees, Dai; Gleeson, Nigel

    2012-01-01

    The effects of serial episodes of fatigue and recovery on volitional and magnetically evoked neuromuscular performance of the knee flexors were assessed in 20 female soccer players during: (i) an intervention comprising 4 × 35 s maximal static exercise, and (ii) a control condition. Volitional peak force was impaired progressively (-16% vs. baseline: 235.3 ± 54.7 to 198.1 ± 38.5 N) by the fatiguing exercise and recovered to within -97% of baseline values following 6 min of rest. Evoked peak twitch force was diminished subsequent to the fourth episode of exercise (23.3%: 21.4 ± 13.8 vs. 16.4 ± 14.6 N) and remained impaired at this level throughout the recovery. Impairment of volitional electromechanical delay performance following the first episode of exercise (25.5%: 55.3 ± 11.9 vs. 69.5 ± 24.5 ms) contrasted with concurrent improvement (10.0%: 24.5 ± 4.7 vs. 22.1 ± 5.0 ms) in evoked electromechanical delay (P exercise provoked substantial impairments to volitional strength and volitional electromechanical delay that showed differential patterns of recovery. However, improved evoked electromechanical delay performance might identify a dormant capability for optimal muscle responses during acute stressful exercise and an improved capacity to maintain dynamic joint stability during critical episodes of loading.

  15. Volitional components of consciousness vary across wakefulness, dreaming and lucid dreaming

    Directory of Open Access Journals (Sweden)

    Martin eDresler

    2014-01-01

    Full Text Available Consciousness is a multifaceted concept; its different aspects vary across species, vigilance states or health conditions. While basal aspects of consciousness like perceptions and emotions are present in many states and species, higher-order aspects like reflective or volitional capabilities seem to be most pronounced in awake humans. Here we assess the experience of volition across different states of consciousness: 10 frequent lucid dreamers rated different aspects of volition according to the Volitional Components Questionnaire for phases of normal dreaming, lucid dreaming and wakefulness. Overall, experienced volition was comparable for lucid dreaming and wakefulness, and rated significantly higher for both states compared to non-lucid dreaming. However, three subscales showed specific differences across states of consciousness: planning ability was most pronounced during wakefulness, intention enactment most pronounced during lucid dreaming, and self-determination most pronounced during both wakefulness and lucid dreaming. Our data confirm the multifaceted nature of consciousness: different higher-order aspects of consciousness are differentially expressed across different conscious states.

  16. Volitional components of consciousness vary across wakefulness, dreaming and lucid dreaming.

    Science.gov (United States)

    Dresler, Martin; Eibl, Leandra; Fischer, Christian F J; Wehrle, Renate; Spoormaker, Victor I; Steiger, Axel; Czisch, Michael; Pawlowski, Marcel

    2014-01-01

    Consciousness is a multifaceted concept; its different aspects vary across species, vigilance states, or health conditions. While basal aspects of consciousness like perceptions and emotions are present in many states and species, higher-order aspects like reflective or volitional capabilities seem to be most pronounced in awake humans. Here we assess the experience of volition across different states of consciousness: 10 frequent lucid dreamers rated different aspects of volition according to the Volitional Components Questionnaire for phases of normal dreaming, lucid dreaming, and wakefulness. Overall, experienced volition was comparable for lucid dreaming and wakefulness, and rated significantly higher for both states compared to non-lucid dreaming. However, three subscales showed specific differences across states of consciousness: planning ability was most pronounced during wakefulness, intention enactment most pronounced during lucid dreaming, and self-determination most pronounced during both wakefulness and lucid dreaming. Our data confirm the multifaceted nature of consciousness: different higher-order aspects of consciousness are differentially expressed across different conscious states.

  17. Measuring motivation and volition of nursing students in nontraditional learning environments.

    Science.gov (United States)

    Nagelsmith, Laurie; Bryer, Jason; Yan, Zheng

    2012-01-01

    The purpose of this study was to identify the best fitting model to represent interrelationships between motivation, volition, and academic success for adult nursing students learning in nontraditional environments. Participants (N=297) completed a survey that incorporated two measures: the Motivated Strategies for Learning Questionnaire (MSLQ) and the academic volitional strategies inventory (AVSI) as well as demographic information. Exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM) were used for data analysis. In phase 1, EFA resulted in factors that generally aligned with previous theoretical factors as defined by the psychometrics used. In Phase 2 of the analysis, CFA validated the use of predefined factor structures. In Phase 3, SEM analysis revealed that motivation has a larger effect on grade point average (GPA; beta = .28, p motivation and volition (r = .42, p motivation, volition, and academic success for adult learners studying in nontraditional learning environments. These findings are consistent with and elaborate the relationship between motivation and volition with a population and setting underrepresented in the research.

  18. Volitional components of consciousness vary across wakefulness, dreaming and lucid dreaming

    Science.gov (United States)

    Dresler, Martin; Eibl, Leandra; Fischer, Christian F. J.; Wehrle, Renate; Spoormaker, Victor I.; Steiger, Axel; Czisch, Michael; Pawlowski, Marcel

    2014-01-01

    Consciousness is a multifaceted concept; its different aspects vary across species, vigilance states, or health conditions. While basal aspects of consciousness like perceptions and emotions are present in many states and species, higher-order aspects like reflective or volitional capabilities seem to be most pronounced in awake humans. Here we assess the experience of volition across different states of consciousness: 10 frequent lucid dreamers rated different aspects of volition according to the Volitional Components Questionnaire for phases of normal dreaming, lucid dreaming, and wakefulness. Overall, experienced volition was comparable for lucid dreaming and wakefulness, and rated significantly higher for both states compared to non-lucid dreaming. However, three subscales showed specific differences across states of consciousness: planning ability was most pronounced during wakefulness, intention enactment most pronounced during lucid dreaming, and self-determination most pronounced during both wakefulness and lucid dreaming. Our data confirm the multifaceted nature of consciousness: different higher-order aspects of consciousness are differentially expressed across different conscious states. PMID:24427149

  19. Evaluation of methods for extraction of the volitional EMG in dynamic hybrid muscle activation

    Directory of Open Access Journals (Sweden)

    Mizrahi Joseph

    2006-11-01

    Full Text Available Abstract Background Hybrid muscle activation is a modality used for muscle force enhancement, in which muscle contraction is generated from two different excitation sources: volitional and external, by means of electrical stimulation (ES. Under hybrid activation, the overall EMG signal is the combination of the volitional and ES-induced components. In this study, we developed a computational scheme to extract the volitional EMG envelope from the overall dynamic EMG signal, to serve as an input signal for control purposes, and for evaluation of muscle forces. Methods A "synthetic" database was created from in-vivo experiments on the Tibialis Anterior of the right foot to emulate hybrid EMG signals, including the volitional and induced components. The database was used to evaluate the results obtained from six signal processing schemes, including seven different modules for filtration, rectification and ES component removal. The schemes differed from each other by their module combinations, as follows: blocking window only, comb filter only, blocking window and comb filter, blocking window and peak envelope, comb filter and peak envelope and, finally, blocking window, comb filter and peak envelope. Results and conclusion The results showed that the scheme including all the modules led to an excellent approximation of the volitional EMG envelope, as extracted from the hybrid signal, and underlined the importance of the artifact blocking window module in the process. The results of this work have direct implications on the development of hybrid muscle activation rehabilitation systems for the enhancement of weakened muscles.

  20. Job insecurity and well-being in the temporary workforce : Testing volition and contract expectations as boundary conditions

    NARCIS (Netherlands)

    Bernhard-Oettel, C.; Rigotti, T.; Clinton, M.; de Jong, J.P.

    2013-01-01

    This study investigates whether temporary contract volition and workers' expectations for contract renewal are boundary conditions to explain differences in temporary workers' job insecurity feelings and well-being. It is hypothesized that (1) low volition through higher job insecurity indirectly

  1. Planning, preparation, execution, and imagery of volitional action.

    Science.gov (United States)

    Deecke, L

    1996-03-01

    There are different motor sets, which a human subject can be in or act from: he or she can be in a self-initiated voluntary movement set (action) or in a response set (re-action). Also, imagery sets are available that are necessary for the acquisition and practice of skill. Most important are such imagery sets for rehearsal in theatre, dance, music, sports, combat, etc.

  2. Planning, preparation, execution, and imagery of volitional action

    OpenAIRE

    Deecke, Lüder

    1996-01-01

    There are different motor sets, which a human subject can be in or act from: He or she can be in a self-initiated voluntary movement set (action) or in a response set (re-action). Also, imagery sets are available that are necessary for the acquisition and practice of skill. Most important are such imagery sets for rehearsal in theatre, dance, music, sports, combat, etc.

  3. Genetics Home Reference: ocular albinism

    Science.gov (United States)

    ... Facebook Twitter Home Health Conditions ocular albinism ocular albinism Printable PDF Open All Close All Enable Javascript to view the expand/collapse boxes. Description Ocular albinism is a genetic condition that primarily affects the ...

  4. A case of severe airbag related ocular alkali injury.

    Science.gov (United States)

    Barnes, Shawn S; Wong, William; Affeldt, John C

    2012-08-01

    While airbags have saved many lives and are clearly beneficial overall, sodium hydroxide (NaOH) powder produced by the inflation reaction can cause significant alkali ocular injury if not irrigated promptly. Here we report a case of severe airbag related ocular alkali injury as a way to bring attention to the need for prompt ocular irrigation following motor vehicle accidents (MVA) with airbag deployment. A 47-year-old man was involved in a MVA with airbag deployment in a rural setting. Attention was paid to several other life-threatening traumatic injuries, however, ocular irrigation was not performed until some 6-7 hours after the MVA. Over the course of 6 months, airbag related alkali injury caused severe limbal ischemia, conjunctivalization of the cornea, corneal epithelial defects, cicatricial scarring, haze, and corneal/limbal vascularization despite amniotic membrane graft. Awareness of the importance of ocular irrigation following airbag deployment must be raised both in the ophthalmology and emergency medicine communities.

  5. Building Self-Discipline to Promote Learning: Students' Volitional Strategies to Navigate the Demands of Schooling

    Science.gov (United States)

    Elstad, Eyvind

    2008-01-01

    Volitional issues are important in today's classrooms where autonomous students are expected to manage school demands on their own. A new kind of challenge has appeared with the advent of free Internet access in the classroom. Motivational conflicts may therefore arise between (1) immediate rewards of electronic chatting, surfing, and games and…

  6. Volitional components of consciousness vary across wakefulness, dreaming and lucid dreaming

    NARCIS (Netherlands)

    Dresler, M.; Eibl, L.; Fischer, C.F.; Wehrle, R.; Spoormaker, V.I.; Steiger, A.; Czisch, M.; Pawlowski, M.

    2014-01-01

    Consciousness is a multifaceted concept; its different aspects vary across species, vigilance states, or health conditions. While basal aspects of consciousness like perceptions and emotions are present in many states and species, higher-order aspects like reflective or volitional capabilities seem

  7. Glycogenin activity and mRNA expression in response to volitional exhaustion in human skeletal muscle

    DEFF Research Database (Denmark)

    Shearer, Jane; Graham, Terry E.; Battram, Danielle S.

    2005-01-01

    ) exercised to volitional exhaustion (Exh) on a cycle ergometer at 75% maximal O2 uptake. Muscle biopsies were obtained at rest, 30 min, and Exh (99 ± 10 min). At rest, total glycogen concentration was 497 ± 41 and declined to 378 ± 51 mmol glucosyl units/kg dry wt following 30 min of exercise (P

  8. Neurophysiology and Neuroanatomy of Reflexive and Volitional Saccades: Evidence from Studies of Humans

    Science.gov (United States)

    McDowell, Jennifer E.; Dyckman, Kara A.; Austin, Benjamin P.; Clementz, Brett A.

    2008-01-01

    This review provides a summary of the contributions made by human functional neuroimaging studies to the understanding of neural correlates of saccadic control. The generation of simple visually guided saccades (redirections of gaze to a visual stimulus or pro-saccades) and more complex volitional saccades require similar basic neural circuitry…

  9. Age of Onset of Bilingualism, Language Use, and the Volitional Subjunctive in Heritage Learners of Spanish

    Science.gov (United States)

    Mikulski, Ariana M.

    2010-01-01

    The present study investigates heritage learners' recognition of native-like and non-native-like mood selection in Spanish volitional constructions along two dimensions: age of onset of bilingualism in English (operationalized as age of arrival) and language use. Thirty-two heritage learners completed a grammaticality judgment (GJ) and an editing…

  10. Neural correlates of the affective properties of spontaneous and volitional laughter types.

    Science.gov (United States)

    Lavan, Nadine; Rankin, Georgia; Lorking, Nicole; Scott, Sophie; McGettigan, Carolyn

    2017-01-27

    Previous investigations of vocal expressions of emotion have identified acoustic and perceptual distinctions between expressions of different emotion categories, and between spontaneous and volitional (or acted) variants of a given category. Recent work on laughter has identified relationships between acoustic properties of laughs and their perceived affective properties (arousal and valence) that are similar across spontaneous and volitional types (Bryant & Aktipis, 2014; Lavan et al., 2016). In the current study, we explored the neural correlates of such relationships by measuring modulations of the BOLD response in the presence of itemwise variability in the subjective affective properties of spontaneous and volitional laughter. Across all laughs, and within spontaneous and volitional sets, we consistently observed linear increases in the response of bilateral auditory cortices (including Heschl's gyrus and superior temporal gyrus [STG]) associated with higher ratings of perceived arousal, valence and authenticity. Areas in the anterior medial prefrontal cortex (amPFC) showed negative linear correlations with valence and authenticity ratings across the full set of spontaneous and volitional laughs; in line with previous research (McGettigan et al., 2015; Szameitat et al., 2010), we suggest that this reflects increased engagement of these regions in response to laughter of greater social ambiguity. Strikingly, an investigation of higher-order relationships between the entire laughter set and the neural response revealed a positive quadratic profile of the BOLD response in right-dominant STG (extending onto the dorsal bank of the STS), where this region responded most strongly to laughs rated at the extremes of the authenticity scale. While previous studies claimed a role for right STG in bipolar representation of emotional valence, we instead argue that this may in fact exhibit a relatively categorical response to emotional signals, whether positive or negative

  11. Relationship between volition, physical activity and weight loss maintenance: Study rationale, design, methods and baseline characteristics.

    Science.gov (United States)

    Dandanell, Sune; Elbe, Anne-Marie; Pfister, Gertrud; Elsborg, Peter; W Helge, Jørn

    2017-05-01

    To investigate the relationship between volition, physical activity and weight loss maintenance. We recruited 84 sedentary (maximal oxygen uptake: 25 ± 5 ml/min), overweight and obese (Body mass index (BMI) 38 ± 7 m/h2, fat 44 ± 7 %) women ( n = 55) and men ( n = 29) for an interdisciplinary prospective study with follow-up. The change in lifestyle and weight loss is promoted via a 3-month intensive lifestyle intervention at a private health school. The intervention consists of supervised training (1-3 hours/day), a healthy hypo-caloric diet (-500 to -700 kCal/day) and education in healthy lifestyle in classes/groups. The participants' body weight and composition (Dual Energy X-ray absorptiometry), volitional skills (questionnaire), physical activity level (heart rate accelerometer/questionnaire) and maximal oxygen uptake (indirect calorimetry) are to be monitored before, after, and 3 and 12 months after the intervention. At the 12-month follow-up, three different groups will be established: Clinical weight loss maintenance (> 10% weight loss from baseline), moderate weight loss maintenance (1-10% weight loss) and no weight loss (or weight regain). A linear mixed model analysis will be used to compare levels of volitional skills, physical activity and maximal oxygen uptake over time, between the three groups. Correlational analyses will be used to investigate possible associations between volition, maximal oxygen uptake, physical activity level and weight loss maintenance. If specific volitional skills are identified as predictors of adherence to physical activity and success in clinical weight loss maintenance, these can be trained in future intensive lifestyle interventions in order to optimize the success rate.

  12. Miopatia ocular descendente Descending ocular myopathy

    Directory of Open Access Journals (Sweden)

    Nunjo Finkel

    1972-06-01

    Full Text Available São relatados 4 casos de miopatia ocular descendente (MOD com história familial levantada em três gerações. Biópsia musculares e eletromiografia em um caso confirmaram o caráter miogênico da doença. A MOD nada mais seria do que uma forma clínica especial de distrofia muscular, de início tardio.Four cases of the so-called descending ocular myopathy with a family history in three generations are reported. In the first case muscular biopsy and electromyographic studies proved the myogenic nature of the process. Descending ocular myopathy seems to be just a clinical form of muscular distrophy of late onset.

  13. Epidemiology of Ocular Toxoplasmosis

    NARCIS (Netherlands)

    Petersen, E.; Kijlstra, A.; Stanford, M.

    2012-01-01

    Retinal infection with Toxoplasma gondii is the most important cause of posterior uveitis, whereby prevalence and incidence of ocular symptoms after infection depend on socio-economic factors and the circulating parasite genotypes. Ocular toxoplasmosis is more common in South America, Central

  14. Paintball ocular injuries.

    Science.gov (United States)

    Kruger, L P; Acton, J K

    1999-03-01

    Six cases of ocular injury following paintball injuries sustained during war games are described. A CO2-powered rifle shoots a 14 mm plastic-coated paintball at participants. The muzzle velocity of the gun is 250 ft/sec (76 m/sec). Locally manufactured paintballs are harder than the more expensive imported varieties and may account for the severity of our reported injuries. Six patients presented to a retinal specialist with various ocular injuries, predominantly of the posterior pole. All patients were young males. There were no cases of ocular penetration. A variety of retinal pathologies was noted, with three cases requiring surgery; however this did not significantly improve the visual outcome. These cases highlight the severe ocular injuries that may occur from paintball injuries. Recommendations to avoid ocular injury are made.

  15. Ocular Emergencies: Red Eye.

    Science.gov (United States)

    Tarff, Andreina; Behrens, Ashley

    2017-05-01

    "Red eye" is used as a general term to describe irritated or bloodshot eyes. It is a recognizable sign of an acute/chronic, localized/systemic underlying inflammatory condition. Conjunctival injection is most commonly caused by dryness, allergy, visual fatigue, contact lens overwear, and local infections. In some instances, red eye can represent a true ocular emergency that should be treated by an ophthalmologist. A comprehensive assessment of red eye conditions is required to preserve the patients visual function. Severe ocular pain, significant photophobia, decreased vision, and history of ocular trauma are warning signs demanding immediate ophthalmological consultation. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Felt or false smiles? Volitional regulation of emotional expression in 4-, 6-, and 8-year-old children.

    Science.gov (United States)

    Kromm, Helena; Färber, Mechthild; Holodynski, Manfred

    2015-01-01

    The development of volitional emotion regulation of expression was examined with a modified disappointing gift paradigm and strategy for coding children's expressions. Forty-nine boys and 49 girls aged 4, 6, and 8 were motivated to volitionally deceive an observer by false smiling, regardless of whether they received an attractive, unattractive, or no gift. Ten naïve observers watched children's videotaped behavior in random order and judged the quality of emotion and type of gift. This impression analysis indicated that children's competence to volitionally regulate their expressions increased with age. In addition, this ability was positively associated with children's emotion understanding of how to differentiate between emotion and expression. Unexpectedly, girls did not display a superior volitional regulation of expression than boys. © 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.

  17. Reflexive and volitional voice fundamental frequency responses to an anticipated feedback pitch error.

    Science.gov (United States)

    Burnett, Theresa A; McCurdy, Katie E; Bright, Jessica C

    2008-11-01

    The pitch-shift reflex is a corrective voice fundamental frequency (F0) response triggered by a sudden shift or "error" in auditory feedback pitch. We investigated how anticipating a voice pitch error affects the pitch-shift reflex and volitional voice F0 responses. Adults sustained the vowel/u/at a comfortable pitch and pressed a button to deliver a 100 cent, 100 ms auditory feedback pitch shift immediately or after a random delay. Pitch shift direction was either constant (up) or randomized (up or down). Onset anticipation often resulted in an anticipatory voice F0 change, but stimulus direction predictability did not affect the responses. When pitch error onset and direction were both anticipated, some participants produced an ideomotor voice F0 change that partially imitated the error, but they produced no apparent pitch-shift reflex. Results imply that when voice pitch errors are anticipated, volitional voice F0 responses may reduce or enhance voice F0 stability.

  18. Challenging ocular image recognition

    Science.gov (United States)

    Pauca, V. Paúl; Forkin, Michael; Xu, Xiao; Plemmons, Robert; Ross, Arun A.

    2011-06-01

    Ocular recognition is a new area of biometric investigation targeted at overcoming the limitations of iris recognition performance in the presence of non-ideal data. There are several advantages for increasing the area beyond the iris, yet there are also key issues that must be addressed such as size of the ocular region, factors affecting performance, and appropriate corpora to study these factors in isolation. In this paper, we explore and identify some of these issues with the goal of better defining parameters for ocular recognition. An empirical study is performed where iris recognition methods are contrasted with texture and point operators on existing iris and face datasets. The experimental results show a dramatic recognition performance gain when additional features are considered in the presence of poor quality iris data, offering strong evidence for extending interest beyond the iris. The experiments also highlight the need for the direct collection of additional ocular imagery.

  19. Pediatric Ocular Trauma

    Science.gov (United States)

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Pediatric Ocular Trauma What causes eye injuries ? Injuries to the ... only the eyelid but the structures that drain tears from the eye. Lacerations of the eyelid or ...

  20. Ocular rosacea: a review

    Directory of Open Access Journals (Sweden)

    Ana Carolina Cabreira Vieira

    2012-10-01

    Full Text Available Rosacea is a prevalent chronic cutaneous disorder with variable presentation and severity. Although considered a skin disease, rosacea may evolve the eyes in 58-72% of the patients, causing eyelid and ocular surface inflammation. About one third of the patients develop potentially sight-threatening corneal involvement. Untreated rosacea may cause varying degrees of ocular morbidity. The importance of early diagnosis and adequate treatment cannot be overemphasized. There is not yet a diagnostic test for rosacea. The diagnosis of ocular rosacea relies on observation of clinical features, which can be challenging in up to 90% of patients in whom accompanying roseatic skin changes may be subtle or inexistent. In this review, we describe the pathophysiologic mechanisms proposed in the literature, clinical features, diagnosis and management of ocular rosacea, as well as discuss the need for a diagnostic test for the disease.

  1. Pediatric genetic ocular tumors

    OpenAIRE

    Rouhani, Behnaz; Ramasubramanian, Aparna

    2014-01-01

    Pediatric genetic ocular tumors include malignancies like retinoblastoma and phakomatosis like neurofibromatosis, tuberous sclerosis, von Hippel-Lindau syndrome, and nevoid basal cell carcinoma syndrome. It is important to screen for ocular tumors both for visual prognosis and also for systemic implications. The phakomatosis comprise of multitude of benign tumors that are aysmptomatic but their detection can aid in the diagnosis of the syndrome. Retinoblastoma is the most common malignant int...

  2. The meta-volition model: organizational leadership is the key ingredient in getting society moving, literally!

    Science.gov (United States)

    Yancey, Antronette K

    2009-10-01

    This paper argues that substantive and sustainable population-wide improvements in physical activity can be achieved only through the large scale adoption and implementation of policies and practices that make being active the default choice and remaining inactive difficult. Meta-volition refers to the volition and collective agency of early adopter leaders who implement such changes in their own organizations to drive productivity and health improvements. Leaders, themselves, are motivated by strong incentives to accomplish their organizational missions. The meta-volition model (MVM) specifies a cascade of changes that may be sparked by structural integration of brief activity bouts into organizational routine across sectors and types of organizations. MVM builds upon inter-disciplinary social ecological change models and frameworks such as diffusion of innovations, social learning and social marketing. MVM is dynamic rather than static, integrating biological influences with psychological factors, and socio-cultural influences with organizational processes. The model proposes six levels of dissemination triggered by organizational marketing to early adopter leaders carried out by "sparkplugs," boisterous leaders in population physical activity promotion: initiating (leader-leader), catalyzing (organizational-individual), viral marketing (individual-organizational), accelerating (organizational-organizational), anchoring (organizational-community) and institutionalizing (community-individual). MVM embodies public-private partnership principles, a collective investment in the high cost of achieving and maintaining active lifestyles.

  3. Carbohydrate mouth rinse improves cycling performance carried out until the volitional exhaustion.

    Science.gov (United States)

    Bavaresco Gambassi, Bruno; Gomes de Santana Barros Leal, Ylana; Pinheiro Dos Anjos, Edson R; Antonelli, Bruna A; Gomes Gonçalves E Silva, Daniela C; Pires de Mélo Montenegro, Iracema H; di Cássia de Oliveira Angelo, Rita; Correia Moura, Isis S; Schwingel, Paulo A

    2017-11-17

    Carbohydrates (CHO) are among the most investigated nutritional ergogenic aids, and may be consumed in different forms, e.g., mouth rinse with carbohydrate solution (MRCS). In this sense, the aim of this study was to evaluate the impact of MRCS on the performance of physically active individuals undergoing a physical exercise session carried out until the volitional exhaustion. This is a counter-balanced randomized study, with a double-blind design. The sample consisted of twenty-one physically active healthy men with a mean (±SD) of age of 22.4 (±2.7) years old, 76.7 (±6.0) cm of height,12.1% (±3.7) of body fat mass, and 23.9 (±2.4) kg/m2 of body mass index. After familiarizing the participants with the protocol (cycle ergometer, with oral mouth rinse procedure) and assessing the maximal lactate steady state the cycling exercise was performed until the volitional exhaustion in the following conditions: without mouth rinse (CONTROL), PLACEBO and MRCS. Time to reach exhaustion was statistically different (pexhaustion until the volitional exhaustion. Thus, the use of methodology proposed by the present study may help coaches and practitioners improve the performance of physically active young adults.

  4. Vestibulo-ocular reflex.

    Science.gov (United States)

    Dieterich, M; Brandt, T

    1995-02-01

    Recent animal and clinical studies on the vestibulo-ocular reflex deal with a number of physiological and clinical aspects from which three were chosen for this review: (1) the torsional vestibulo-ocular reflex and its disorders; (2) the otolith contribution to the vestibulo-ocular reflex; and (3) neurotransmitters, neuropharmacological aspects, and medical treatment. Disorders of the vestibulo-ocular reflex can be classified according to the three major planes of action, yaw plane, pitch plane, and roll plane, which equate with horizontal nystagmus, upbeat or downbeat nystagmus, and torsional nystagmus, respectively. The particular interest in the torsional vestibulo-ocular reflex arises from new methods for measuring ocular torsion, especially the three-dimensional eye-movement recordings with scleral coils. These methods make it possible to do three-dimensional analysis of the differential effects of horizontal and vertical semicircular canal function and their individual disorders of the torsional vestibulo-ocular reflex. Otolith and semicircular canal inputs converge at the level of the vestibular nuclei to subserve static graviceptive and dynamic torsional and pitch function. The elaboration of the particular sensorial weight of the input from either the otoliths or the semicircular canal is currently a challenge for both physiologists and neurologists. Disorders of otolith function, still absent from the diagnostic repertoire of most neurologists, are increasingly being reported. The most promising developments in therapeutic measures may come from research on vestibular neurotransmitters, their agonists and antagonists. A number of pharmacological agents are effective suppressants of pathological eye movements. However, systematic prospective studies are needed.(ABSTRACT TRUNCATED AT 250 WORDS)

  5. Characterizing differential poststroke corticomotor drive to the dorsi- and plantarflexor muscles during resting and volitional muscle activation.

    Science.gov (United States)

    Palmer, Jacqueline A; Zarzycki, Ryan; Morton, Susanne M; Kesar, Trisha M; Binder-Macleod, Stuart A

    2017-04-01

    Imbalance of corticomotor excitability between the paretic and nonparetic limbs has been associated with the extent of upper extremity motor recovery poststroke, is greatly influenced by specific testing conditions such as the presence or absence of volitional muscle activation, and may vary across muscle groups. However, despite its clinical importance, poststroke corticomotor drive to lower extremity muscles has not been thoroughly investigated. Additionally, whereas conventional gait rehabilitation strategies for stroke survivors focus on paretic limb foot drop and dorsiflexion impairments, most contemporary literature has indicated that paretic limb propulsion and plantarflexion impairments are the most significant limiters to poststroke walking function. The purpose of this study was to compare corticomotor excitability of the dorsi- and plantarflexor muscles during resting and active conditions in individuals with good and poor poststroke walking recovery and in neurologically intact controls. We found that plantarflexor muscles showed reduced corticomotor symmetry between paretic and nonparetic limbs compared with dorsiflexor muscles in individuals with poor poststroke walking recovery during active muscle contraction but not during rest. Reduced plantarflexor corticomotor symmetry during active muscle contraction was a result of reduced corticomotor drive to the paretic muscles and enhanced corticomotor drive to the nonparetic muscles compared with the neurologically intact controls. These results demonstrate that atypical corticomotor drive exists in both the paretic and nonparetic lower limbs and implicate greater severity of corticomotor impairments to plantarflexor vs. dorsiflexor muscles during muscle activation in stroke survivors with poor walking recovery.NEW & NOTEWORTHY The present study observed that lower-limb corticomotor asymmetry resulted from both reduced paretic and enhanced nonparetic limb corticomotor excitability compared with

  6. Impaired volitional closure of the left eyelid after right anterior cerebral artery infarction: apraxia due to interhemispheric disconnection?

    Science.gov (United States)

    Korn, Thomas; Reith, Wolfgang; Becker, Georg

    2004-02-01

    The inability of volitional unilateral eyelid closure is an uncommon symptom of a central nervous system disorder. When it occurs as the result of a localized brain lesion, it is debated to be a form of supranuclear facial palsy or an apraxic phenomenon. To report and discuss a unilateral (left-sided) higher-order movement disorder of the facial periocular musculature bearing apraxic features. University neurology department. A 78-year-old right-handed man was admitted to the hospital with a left-sided brachiofacial hemiparesis of sudden onset. After thrombolysis with intravenous recombinant tissue-type plasminogen activator, the hemiparesis, including the left-sided facial weakness, disappeared. Serial computed tomographic scans showed that the patient was left with a stroke in the right anterior cerebral artery territory, affecting the frontal commissural fibers of the corpus callosum. There were no signs of upper motor neuron facial paresis on the left side when gesturing in a natural context. Eyelid closure was complete during sleep. However, left eyelid closure and elevation of the left eyebrow were not possible on verbal command. In contrast, voluntary innervation of the perioral facial musculature was performed properly. The voluntary-automatic dissociation of our patient's eyelid closure was suggestive of an apraxic disorder. Disconnection from a praxis center caused by callosal damage may be assumed to be the underlying cause. The unilaterality of the symptom might imply that in a bilaterally organized corticonuclear system such as upper face innervation, it is the crossing fibers that are primarily involved in praxis tasks.

  7. Pediatric genetic ocular tumors.

    Science.gov (United States)

    Rouhani, Behnaz; Ramasubramanian, Aparna

    2014-12-01

    Pediatric genetic ocular tumors include malignancies like retinoblastoma and phakomatosis like neurofibromatosis, tuberous sclerosis, von Hippel-Lindau syndrome, and nevoid basal cell carcinoma syndrome. It is important to screen for ocular tumors both for visual prognosis and also for systemic implications. The phakomatosis comprise of multitude of benign tumors that are aysmptomatic but their detection can aid in the diagnosis of the syndrome. Retinoblastoma is the most common malignant intraocular tumor in childhood and with current treatment modalities, the survival is more than 95%. It is transmitted as an autosomal dominant fashion and hence the offsprings of all patients with the germline retinoblastoma need to be screened from birth. This review discusses the various pediatric genetic ocular tumors discussing the clinical manifestation, diagnosis and treatment.

  8. Artefactos en ultrasonido ocular

    Directory of Open Access Journals (Sweden)

    Mariana Mayorquín Ruiz

    2016-07-01

    Full Text Available El ultrasonido ocular es un estudio dependiente del operador. Un buen estudio ecográfico debe tener como base el conocimiento de la anatomía y fisiología normales y de los cambios producidos en diferentes enfermedades, así como los cambios tras una cirugía ocular o trauma. El conocimiento de los fenómenos físicos producidos por el ultrasonido es la base para entender y reconocer la presencia de artefactos en el ultrasonido ocular. Esta revisión tiene como objetivo hacer un recuento de los artefactos que pueden ocasionar confusión al interpretar una imagen ecográfica, así como explicar la base física en la que se basan, reduciendo de esta manera los errores de interpretación y diagnósticos.

  9. Taser penetrating ocular injury.

    Science.gov (United States)

    Ng, Weng; Chehade, Mark

    2005-04-01

    To describe the presentation and treatment of a Taser penetrating ocular injury. Case report. A 50-year-old man with a Taser injury 1.5 cm below the right lower eyelid margin was admitted to the emergency department of a tertiary hospital. The case report describes the ophthalmic assessment, investigation, treatment, and outcome of the Taser barb penetrating ocular injury. The Taser has a fish hook barb that caused a full-thickness wound adequately large for vitreous to escape when the Taser was removed. Consequently, the scleral wound was repaired and cryopexy was performed. The affected eye made a satisfactory recovery, and the visual acuity was 6/9 with a pinhole 1 week after operation. Any Taser injury around the orbits should raise the suspicion of a penetrating ocular injury. In likely cases, removal of the Taser should be performed in an operating theater under general anesthesia.

  10. Feline ocular emergencies.

    Science.gov (United States)

    Giuliano, Elizabeth A

    2005-05-01

    Feline ocular emergencies include any ophthalmic condition that has rapidly developed or is the result of trauma to the eye or periocular structures. Common feline emergencies include proptosis, lid lacerations, corneal ulcers, and foreign bodies. Complete ophthalmic examination including procurement of the minimal ophthalmic database (Schirmer tear test, fluorescein stain, and intraocular pressure measurement) should be obtained whenever possible to ensure that the complete and correct diagnosis is made. Concern for the patient's vision and ocular comfort should guide the practioner's diagnostic and therapeutic plan. This article reviews some of the more common feline ocular emergencies, including conditions affecting the orbit and globe, adnexa, conjunctiva, and cornea. Feline uveitis, glaucoma, and lenticular diseases are covered more thoroughly elsewhere in this issue.

  11. What Is an Ocular Migraine?

    Science.gov (United States)

    ... When to seek help What is an ocular migraine? Is it a sign of something serious? Answers ... and retinal migraine, which could signal something serious. Migraine aura affecting your vision Ocular migraine sometimes describes ...

  12. Combat Ocular Problems. Supplement,

    Science.gov (United States)

    1982-04-01

    Brooks Air Force Base, TX: USAF School of Aerospace Medicine, 1978 6. BROWNELL , A.S., and B.E. STUCK. Ocular and skin hazards from C02 laser...acuity following laser radiation. In: Proceedings of the Human Factors Society. 1980. pp 162-166 9. KELLY , D.H. Photopic contrast sensitivity without

  13. Ocular Adnexal Follicular Lymphoma

    DEFF Research Database (Denmark)

    Rasmussen, Peter K; Coupland, Sarah E; Finger, Paul T

    2014-01-01

    IMPORTANCE The clinical features of the follicular subtype of ocular adnexal lymphoma (OAL) have not been previously evaluated in a large cohort. OBJECTIVE To characterize the clinical features of follicular OAL. DESIGN, SETTING, AND PARTICIPANTS We performed a retrospective multicenter study tha...

  14. Ocular straylight in albinism

    NARCIS (Netherlands)

    Kruijt, Bastiaan; Franssen, Luuk; Prick, Liesbeth J. J. M.; van Vliet, Johannes M. J.; van den Berg, Thomas J. T. P.

    2011-01-01

    Albinism is an inherited disorder that affects the melanin biosynthesis pathway, which results in reduced or absent pigment formation. This may lead to increased light transmission through the iris and more reflected light from the fundus. Both these effects contribute to the occurrence of ocular

  15. Ocular manifestations of leptospirosis

    Directory of Open Access Journals (Sweden)

    Rathinam S

    2005-01-01

    Full Text Available Leptospiral uveitis is a common entity in tropical countries. Ocular manifestations are noted in the second phase of illness, but these remain under-diagnosed mainly because of the prolonged symptom-free period that separates the systemic manifestations from detection of ocular manifestations.Varying ophthalmic presentations and the intrinsic nature of different types of uveitis to mimic one another also challenge the accuracy of the diagnosis. Of the individual ocular signs, the combination of acute, non-granulomatous, panuveitis, hypopyon, vasculitis, optic disc edema, membranous vitreous opacities and absence of choroiditis or retinitis have high predictive value for the clinical diagnosis of leptospiral uveitis. Geographic location of the patient, occupation, socio-economic status, risk factors related to exposure, past history of fever or jaundice also aid in diagnosis.Steroids are the mainstay of treatment for leptospiral uveitis. Depending upon the severity and anatomical location of inflammatory lesion, topical, peri-ocular and/or systemic steroids are given. The prognosis is generally good, even when the inflammation is severe.

  16. Goldenhar syndrome: ocular features.

    Science.gov (United States)

    Bhallil, S; Benatiya, I; El Abdouni, O; Mahjoubi, B; Hicham, T

    2010-01-01

    Goldenhar syndrome is a rare congenital anomaly which consists of a triad of an ocular dermoid cyst, preauricular skin tags and vertebral dysplasia. We report two cases of Goldenhar syndrome, diagnosed in a 4-year-old girl and in a 20-year-old young adult. The dermoid cyst is a benign tumour with serious ophthalmologic complications.

  17. [Ocular movements and reading: a review].

    Science.gov (United States)

    Quercia, P

    2010-06-01

    A literature review of the important findings discovered over the past three decades on ocular movements during reading is presented herein. This fairly recent function in human evolution is a sophisticated sensorimotor and cognitive activity that brings very complex neurological and motor mechanisms into play. However, knowledge in this field is limited, even though reading problems are very common in children. We collected all the references in PubMed dating from 1969 to 2009 using the following "binocular coordination", "eye movements", "reading", and "dyslexia". When reading, the visual axes move in a very particular way, notably with regard to the parallelism of the ocular axes when saccades are triggered to reach the words to be read and during fixations, which enable decoding. In fact, when reading, the visual axes are often disassociated, even going as far as to intersect in a considerable number of cases. There are relatively few studies that have examined binocular coordination during reading. We are beginning to understand how the ocular axes move during horizontal saccades. Three-dimensional studies could be the next step to providing more precise data. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  18. Volitional personality trait change: Can people choose to change their personality traits?

    Science.gov (United States)

    Hudson, Nathan W; Fraley, R Chris

    2015-09-01

    Previous research has found that most people want to change their personality traits. But can people actually change their personalities just because they want to? To answer this question, we conducted 2, 16-week intensive longitudinal randomized experiments. Across both studies, people who expressed goals to increase with respect to any Big Five personality trait at Time 1 tended to experience actual increases in their self-reports of that trait-as well as trait-relevant daily behavior-over the subsequent 16 weeks. Furthermore, we tested 2 randomized interventions designed to help participants attain desired trait changes. Although 1 of the interventions was inefficacious, a second intervention that trained participants to generate implementation intentions catalyzed their ability to attain trait changes. We also tested several theoretical processes through which volitional changes might occur. These studies suggest that people may be able to change their self-reported personality traits through volitional means, and represent a first step toward understanding the processes that enable people to do so. (c) 2015 APA, all rights reserved).

  19. Breathing above the brainstem: Volitional control and attentional modulation in humans.

    Science.gov (United States)

    Herrero, Jose Luis; Khuvis, Simon; Yeagle, Erin; Cerf, Moran; Mehta, Ashesh D

    2017-09-27

    While the neurophysiology of respiration has traditionally focused on automatic brainstem processes, higher brain mechanisms underlying the cognitive aspects of breathing are gaining increasing interest. Therapeutic techniques have used conscious control and awareness of breathing for millennia with little understanding of the mechanisms underlying their efficacy. Using direct intracranial recordings in humans, we correlated cortical and limbic neuronal activity as measured by the intracranial electroencephalogram (iEEG) with the breathing cycle. We show this to be the direct result of neuronal activity, as demonstrated both by the specificity of the finding to the cortical grey matter and the tracking of breath by the gamma band (40-150 Hz) envelope in these structures. We extend prior observations by showing the iEEG signal to track the breathing cycle across a widespread network of cortical and limbic structures. We further demonstrate a sensitivity of this tracking to cognitive factors using tasks adapted from cognitive behavioral therapy and meditative practice. Specifically, volitional control and awareness of breathing engage distinct but overlapping brain circuits. During volitionally-paced breathing, iEEG-breath coherence increases in a fronto-temporal-insular network, and during attention to breathing, we demonstrate increased coherence in the anterior cingulate, premotor, insular and hippocampal cortices. Our findings suggest that breathing can act as an organizing hierarchical principle for neuronal oscillations throughout the brain, and detail mechanisms of how cognitive factors impact otherwise-automatic neuronal processes during interoceptive attention. Copyright © 2017, Journal of Neurophysiology.

  20. Ocular dangers of fencing wire.

    Science.gov (United States)

    McAllum, P; Barnes, R; Dickson, J

    2001-07-27

    To invesitgate the incidence and severity of penetrating eye injuries caused by fencing wire in the Waikato region. We reviewed the case notes for all penetrating eye injuries treated at Waikato Hospital during the past six years. Parameters recorded were patient age and sex, mechanism of injury, initial visual acuity, characteristics of injury, surgery performed and final visual outcome. The incidence of penetrating eye injuries in the Waikato region was 3.8 per 100,000 per year, based on an estimated catchment population of 350,000. We found fencing wire to be the third most common cause of penetrating eye injury, accounting for 8.8% of injuries, behind motor vehicle accidents and hammering which accounted for 26.3% and 20.0% of injuries, respectively. The fencing wire injuries involved men exclusively, with an average age of 41.7 years. Fencing wire injuries had worse presenting visual acuity than other injuries, involved the posterior segment of the eye more frequently and were more likely to develop bacterial endophthalmitis. They also underwent more surgical procedures and were more commonly associated with a poor visual outcome. Fencing wire is an important cause of visual loss in the Waikato region. We hope to raise awareness of its potential ocular dangers and to promote the use of appropriate eye protection.

  1. Self-reported volitional control in adolescents and young adults from a community cohort: Associations with current, past and future mental disorders.

    Science.gov (United States)

    Asselmann, Eva; Hilbert, Kevin; Hoyer, Jana; Wittchen, Hans-Ulrich; Lieb, Roselind; Bühringer, Gerhard; Beesdo-Baum, Katja

    2017-11-21

    Alterations in volitional control have been found for various mental disorders. However, it remains unclear to which degree such alterations vary by type of psychopathology and constitute preceding vulnerabilities or correlates of mental disorders. DSM-IV mental disorders were assessed among adolescents and young adults from the community at baseline (age 14-24) and in up to 3 follow-up assessments over 10 years (n = 2515) using a standardized diagnostic interview (DIA-X/M-CIDI). Self-reported volitional control was assessed at second follow-up (T2) when subjects were aged 17-28 using the German version of the Short Form of the Volitional Components Inventory. Linear regressions adjusted for sex, age and lifetime disorders revealed that anxiety and affective disorders were associated with widespread alterations in self-reported volitional control (lower self regulation, higher self inhibition and volitional inhibition), while substance use disorders were specifically associated with higher volitional inhibition. Logistic regressions adjusted for sex, age and prior lifetime psychopathology revealed that lower self-reported volitional control at T2 predicted incident panic, social phobia and substance use at T3 (follow-up interval M = 4.8 years). Findings point toward at least partly disorder-specific alterations in volitional control in mental disorders, which might be antecedent vulnerability factors and thus useful to guide early recognition and prevention. Copyright © 2017. Published by Elsevier B.V.

  2. Ocular allergy and keratoconus

    Directory of Open Access Journals (Sweden)

    Namrata Sharma

    2013-01-01

    Full Text Available Keratoconus is the most common corneal ectatic disorder, the cause of which is largely unknown. Many factors have been implicated, and the ocular allergy is being one of them. The commonly proposed pathogenesis includes the release of inflammatory mediators due to eye rubbing which may alter the corneal collagen and lead to corneal ectasias. The onset of keratoconus is often early in cases associated with allergy and routine corneal topography may detect subtle forms of keratoconus. These cases may require early keratoplasty and are at an increased risk of having acute corneal hydrops. Surgical outcomes are similar to primary keratoconus cases. However, post-operative epithelial breakdown may be a problem in these cases. Control of allergy and eye rubbing is the best measure to prevent corneal ectasias in cases of ocular allergy.

  3. Sclerodermatomyositis, ocular manifestations.

    Science.gov (United States)

    Pedroza-Seres, M; Serna-Ojeda, J C; Flores-Suárez, L F

    2017-07-01

    Sclerodermatomyositis is an overlap syndrome of myositis and scleroderma, with dermatological, muscular and joint involvement, but may also present with ocular manifestations. A 57 year-old woman presented with ophthalmological manifestations, including scleral thinning 360°, and the presence of cells in the anterior and posterior chamber. Oriented physical examination and laboratory studies led to the diagnosis, with the need for systemic treatment. Sclerodermatomyositis is a rare disease. Its diagnosis needs thorough clinical and laboratory studies, and its management should be multidisciplinary when inflammatory ocular manifestations may be present. Copyright © 2016 Sociedad Española de Oftalmología. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Ocular Response Analyzer

    OpenAIRE

    Kaushik, Sushmita; Pandav, Surinder Singh

    2012-01-01

    Until recently, corneal biomechanical properties could not be measured in vivo. The ocular response analyzer is a new, noninvasive device that analyses corneal biomechanical properties simply and rapidly. The ORA allows cornea compensated IOP measurements and can estimate corneal hysteresis (CH) and corneal resistance factor (CRF). It is designed to improve the accuracy of IOP measurement by using corneal biomechanical data to calculate a biomechanically adjusted estimate of intraocular press...

  5. Microsporidia: Emerging Ocular Pathogens

    Directory of Open Access Journals (Sweden)

    Joseph J

    2005-01-01

    Full Text Available Microsporidia are eukaryotic, spore forming obligate intracellular parasites, first recognized over 100 years ago. Microsporidia are becoming increasingly recognized as infectious pathogens causing intestinal, ocular, sinus, pulmonary, muscular and renal diseases, in both immunocompetent and immunosuppressed patients. Ocular microsporidiosis, though uncommon, could be isolated or part of systemic infections. It occurs mainly in two forms: keratoconjunctivitis form, mostly seen in immunocompromised individuals; stromal keratitis form seen in immunocomptetant individuals. Recent reports indicate increasing number of cases of ocular microsporidiosis in immunocompetent individuals. The ocular cases present as superficial keratitis in AIDS patients, and these differ in presentation and clinical course from the cases seen in immunocompetent individuals which mainly appear to be as deep stromal keratitis. For most patients with infectious diseases, microbiological isolation and identification techniques offer the most rapid and specific determination of the etiologic agent, however this does not hold true for microsporidia, which are obligate intracellular parasites requiring cell culture systems for growth. Therefore, the diagnosis of microsporidiosis currently depends on morphological demonstration of the organisms themselves, either in scrapings or tissues. Although the diagnosis of microsporidiosis and identification of microsporidia by light microscopy have greatly improved during the last few years, species differentiation by these techniques is usually impossible and electron microscopy may be necessary. Immuno fluorescent-staining techniques have been developed for species differentiation of microsporidia, but the antibodies used in these procedures are available only at research laboratories at present. During the last 10 years, molecular techniques have been developed for the detection and species differentiation of microsporidia.

  6. Human ocular anatomy.

    Science.gov (United States)

    Kels, Barry D; Grzybowski, Andrzej; Grant-Kels, Jane M

    2015-01-01

    We review the normal anatomy of the human globe, eyelids, and lacrimal system. This contribution explores both the form and function of numerous anatomic features of the human ocular system, which are vital to a comprehensive understanding of the pathophysiology of many oculocutaneous diseases. The review concludes with a reference glossary of selective ophthalmologic terms that are relevant to a thorough understanding of many oculocutaneous disease processes. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Miopatia ocular descendente

    Directory of Open Access Journals (Sweden)

    Nunjo Finkel

    1972-06-01

    Full Text Available São relatados 4 casos de miopatia ocular descendente (MOD com história familial levantada em três gerações. Biópsia musculares e eletromiografia em um caso confirmaram o caráter miogênico da doença. A MOD nada mais seria do que uma forma clínica especial de distrofia muscular, de início tardio.

  8. Bilateral ocular osseous choristomas

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Jeung Hee; Yoon, Dae Young; Choi, Chul Soon; Yoon, Eun Joo; Park, Sang Joon; Seo, Young Lan [Hallym University, Department of Radiology, Kangdong Sacred Heart Hospital, Seoul (Korea); Kim, Byoung Jin [Hallym University, Department of Ophthalmology, Kangdong Sacred Heart Hospital, Seoul (Korea)

    2005-11-01

    Choristoma is a benign tumour defined as normal tissue in an ectopic location. Osseous choristoma, one subtype of this entity, occurring within the orbit has rarely been reported in the world literature. We report a 6-year-old girl with bilateral ocular osseous choristomas who presented with palpable nodules protruding from both upper lids. The radiological and clinical findings are described and previous reports are reviewed. (orig.)

  9. Immunohistochemistry in ocular carcinomas.

    Science.gov (United States)

    Sramek, Brett; Lisle, Allison; Loy, Timothy

    2008-07-01

    The distinction between ocular sebaceous carcinoma, poorly differentiated ocular squamous cell carcinoma and ocular basal cell carcinoma can be challenging. An appropriate immunohistochemical panel may help to differentiate these lesions. To determine the distribution and use of several immunostains in these specimens, formalin-fixed, paraffin-embedded tissue from several of each was studied using an immunohistochemical technique. Positive staining for cytokeratin (CK)7 was seen in 100% of sebaceous carcinomas, 77.8% of basal cell carcinomas and 67.7% of squamous cell carcinomas. One hundred percent of sebaceous and basal cell carcinomas were positive for cytokeratin CAM 5.2, while only 83.3% of squamous cell carcinomas were positive. Using epithelial membrane antigen (EMA), 100% of squamous cell carcinomas and 80% of sebaceous carcinomas were positive, while basal cell carcinomas were uniformly negative. One hundred percent of basal cell carcinomas and 80% of sebaceous carcinomas were positive for Ber-EP4, while all squamous cell carcinomas were negative. Finally, 77.8%, 20% and 16.7% of basal cell carcinomas, sebaceous carcinomas and squamous cell carcinomas showed immunoreactivity for the androgen receptor. An EMA positive, Ber-EP4 positive immunophenotype supports sebaceous carcinoma, EMA positive, Ber-EP4 negative result supports squamous cell carcinoma and an EMA negative, Ber-EP4 positive result supports basal cell carcinoma.

  10. Ocular injury in hurling.

    LENUS (Irish Health Repository)

    Flynn, T H

    2012-02-03

    OBJECTIVES: To describe the clinical characteristics of ocular injuries sustained in hurling in the south of Ireland and to investigate reasons for non-use of protective headgear and eye wear. METHODS: Retrospective review of the case notes of 310 patients who attended Cork University Hospital or Waterford Regional Hospital between 1 January 1994 and 31 December 2002 with ocular injuries sustained during a hurling match. A confidential questionnaire on reasons for non-use of protective headgear and eye wear was completed by 130 players. RESULTS: Hurling related eye injuries occurred most commonly in young men. Fifty two patients (17%) required hospital admission, with hyphaema accounting for 71% of admissions. Ten injuries required intraocular surgical INTERVENTION: retinal detachment repair (5); macular hole surgery (1); repair of partial thickness corneal laceration (1); repair of globe perforation (1); enucleation (1); trabeculectomy for post-traumatic glaucoma (1). Fourteen eyes (4.5%) had a final best corrected visual acuity (BCVA) of <6\\/12 and six (2%) had BCVA <3\\/60. In the survey, 63 players (48.5%) reported wearing no protective facemask while playing hurling. Impairment of vision was the most common reason cited for non-use. CONCLUSIONS: Hurling related injury is a significant, and preventable, cause of ocular morbidity in young men in Ireland. The routine use of appropriate protective headgear and faceguards would result in a dramatic reduction in the incidence and severity of these injuries, and should be mandatory.

  11. Ocular Paintball Injuries.

    Science.gov (United States)

    Nemet, Arie Y; Asalee, Leena; Lang, Yaron; Briscoe, Daniel; Assia, Ehud I

    2016-01-01

    Background: One of the most alarming ocular injury trends in recent years has been the proliferation of paintball guns and the proportional increase in the number of ocular eye injuries caused by paintballs. To describe five cases of paintball eye injuries that resulted in loss of functional vision in four of them. We conducted a retrospective review of the clinical course in five patients with paintball eye injuries treated in the ophthalmology departments of two medical centers. Five young males were evaluated for paintball injuries caused by blunt trauma. There was one case of full-thickness laceration (globe rupture). Four patients required one to five surgical interventions: three of these involved the removal of traumatic cataract including two eyes with significant zonular dehiscence treated by lens capsule conservation using anchoring devices, one retinal surgery and two glaucoma filtration surgeries. However, final visual outcome was not favorable due to irreversible retinal damage. Paintball trauma often results in significant ocular injury and loss of functional vision despite successful surgical intervention. Most injuries occur in under-supervised settings and are easily preventable. Improved safety measures, strict regulation enforcement and appropriate public education could prevent such serious damage.

  12. Volitional Regulation and Self-Regulated Learning: An Examination of Individual Differences in Approach-Avoidance Achievement Motivation

    Science.gov (United States)

    Bartels, Jared M.; Magun-Jackson, Susan; Kemp, Arthur D.

    2009-01-01

    Introduction: In the present study we examined the differences in volitional strategy use (i.e., self-efficacy enhancement, negative-based incentives, and stress-reducing actions) and their relation to cognitive self-regulated learning strategy use (i.e., rehearsal, elaboration, organization, and critical thinking) in a sample of university…

  13. Motivational and Volitional Variables Associated with Stages of Change for Exercise in Multiple Sclerosis: A Multiple Discriminant Analysis

    Science.gov (United States)

    Chiu, Chung-Yi; Fitzgerald, Sandra D.; Strand, David M.; Muller, Veronica; Brooks, Jessica; Chan, Fong

    2012-01-01

    The main objective of this study was to determine whether motivational and volitional variables identified in the health action process approach (HAPA) model can be used to successfully differentiate people with multiple sclerosis (MS) in different stages of change for exercise and physical activity. Ex-post-facto design using multiple…

  14. Relationship between volition, physical activity and weight loss maintenance: Study rationale, design, methods and baseline characteristics

    DEFF Research Database (Denmark)

    Dandanell, Sune; Elbe, Anne-Marie; Pfister, Gertrud Ursula

    2017-01-01

    ) for an interdisciplinary prospective study with follow-up. The change in lifestyle and weight loss is promoted via a 3-month intensive lifestyle intervention at a private health school. The intervention consists of supervised training (1–3 hours/day), a healthy hypo-caloric diet (−500 to −700 kCal/day) and education......, and 3 and 12 months after the intervention. Results: At the 12-month followup, three different groups will be established: Clinical weight loss maintenance (> 10% weight loss from baseline), moderate weight loss maintenance (1–10% weight loss) and no weight loss (or weight regain). A linear mixed model...... maintenance. Conclusions: If specific volitional skills are identified as predictors of adherence to physical activity and success in clinical weight loss maintenance, these can be trained in future intensive lifestyle interventions in order to optimize the success rate....

  15. Volition and Motivation's Influence on Weight Loss Maintenance in the Period Following an Intensive Lifestyle Intervention

    DEFF Research Database (Denmark)

    Elsborg, Peter

    Questionnaire was validated in a sample of 836 university students. Six volitional factors based on 18 items of relevance to exercise participation were identified. The questionnaire showed acceptable model fit, internal consistency, convergent validity, and the ability to explain differences in exercise...... or counterproductive depending on the level of selfdetermination, as identified regulation showed a positive effect 12 months after the intervention, whereas internal regulation showed a negative effect on weight loss. In Study 3 – an interview based qualitative study of 11 successful and 4 unsuccessful ILI weight...... maintainers – it was shown that important challenges in the period that follows the ILI were adjusting to life after the intervention, controlling ‘unhealthy’ food intake, and avoiding being controlled by specific situations. Clear differences were seen between successful and unsuccessful weight maintainers...

  16. Functional Neuromuscular Stimulation Controlled by Surface Electromyographic Signals Produced by Volitional Activation of the Same Muscle

    DEFF Research Database (Denmark)

    Sennels, Søren; Biering-Sørensen, Fin; Andersen, Ole Trier

    1997-01-01

    In order to use the volitional electromyography (EMG) as a control signal for the stimulation of the same muscle, it is necessary to eliminate the stimulation artifacts and the muscle responses caused by the stimulation. The stimulation artifacts, caused by the electric field in skin and tissue...... generated by the stimulation current, are relatively easy to eliminate by shutting down the EMG-amplifier at the onset of the stimulation pulses. The muscle response is a nonstationary signal, therefore, an adaptive linear prediction filter is proposed. The filter is implemented and for three filter lengths...... tested on both simulated and real data. The filter performance is compared with a conventional fixed comb filter. The simulations indicate that the adaptive filter is relatively insensitive to variations in amplitude of the muscle responses, and for all filter lengths produces a good filtering...

  17. Saccadic compensation for reflexive optokinetic nystagmus just as good as compensation for volitional pursuit.

    Science.gov (United States)

    Harrison, James J; Freeman, Tom C A; Sumner, Petroc

    2015-01-26

    The natural viewing behavior of moving observers ideally requires target-selecting saccades to be coordinated with automatic gaze-stabilizing eye movements such as optokinetic nystagmus. However, it is unknown whether saccade plans can compensate for reflexive movement of the eye during the variable saccade latency period, and it is unclear whether reflexive nystagmus is even accompanied by extraretinal signals carrying the eye movement information that could potentially underpin such compensation. We show that saccades do partially compensate for optokinetic nystagmus that displaces the eye during the saccade latency period. Moreover, this compensation is as good as for displacements due to voluntary smooth pursuit. In other words, the saccade system appears to be as well coordinated with reflexive nystagmus as it is with volitional pursuit, which in turn implies that extraretinal signals accompany nystagmus and are just as informative as those accompanying pursuit. © 2015 ARVO.

  18. Deficits in volitional oculomotor control align with language status in autism spectrum disorders.

    Science.gov (United States)

    Kelly, David J; Walker, Robin; Norbury, Courtenay Frazier

    2013-01-01

    Eye-tracking paradigms are increasingly used to investigate higher-level social and cognitive processing in autism spectrum disorder (ASD). However, the integrity of the oculomotor system within ASD is unclear, with contradictory reports of aberrant eye-movements on basic oculomotor tasks. The purpose of the current study was to determine whether reducing population heterogeneity and distinguishing neurocognitive phenotypes can clarify discrepancies in oculomotor behaviour evident in previous reports. Reflexive and volitional eye-movement control was assessed in 73 children aged 8-14 years from four distinct groups: Autism Language Normal (ALN), Autism Language Impaired (ALI), non-autistic Language Impaired (LI) and Typically Developing (TD). Eye-movement control was measured using pro- and antisaccade tasks and a novel 'search distracter' task to measure distractibility. Reflexive eye-movements were equivalent across groups, but deficits in volitional eye-movement control were found that aligned with language status, and were not specific to ASD. More than 80% of ALI and LI children presented error rates at least 1.5 SDs below the TD mean in an antisaccade task. In the search distracter task, 35.29% of ALI children and 43.75% of LI children had error rates greater than 1.5 SDs compared with 17.64% of ALN children. A significant proportion of children with neurodevelopmental disorders involving language function have pronounced difficulties suppressing reflexive saccades and maintaining fixations in the presence of competing stimuli. We extend the putative link between ALI and LI populations to non-language tasks, and highlight the need to account for co-morbidity in understanding the ontogenesis of ASD. © 2012 Blackwell Publishing Ltd.

  19. METAPHORIZATION AND METONYMIZATIO: DIACHRONIC DEVELOPMENT OF VERBS OF VOLITION IN SOUTHERN MIN

    Directory of Open Access Journals (Sweden)

    Miao-Hsia Chang

    2009-06-01

    Full Text Available This paper investigates the diachrony of the verbs of volition ai and beh in Southern Min (SM. The data include historical SM texts (16th-19th century, folk songs in the late 19th to early 20th century, and contemporary natural Taiwanese Southern Min conversations. The results mainly mark two stages of the development of ai and beh: historical (before 1900 and contemporary SM. Since the 16th century (Ming Dynasty, ai has been used as a verb of volition indicating love, intention or hope. As for historical ai, it marked future, specialized however for predicting an adverse future. In contemporary SM, a sense of necessity emerged with the use of ai denoting general agreement among people. Seven senses are attributed to historical beh: want/intention/hope, future, excessiveness, necessity, proximity and conditionality. In contemporary SM, the indication of the want of an entity has become a less preferred use, and necessity is only preserved when indicating puzzlement and helplessness. The diachronic developments of ai and beh demonstrate an interplay of metaphorization and metonymization (Traugott and Dasher 2002:27. Metaphorization contributes first to the semantic shift of ai and beh from “to want; to love” to “to intend to” and a concurrent categorical change from lexical verb into auxiliary, and second, to the evolution of future. Metonymization activates an even wider range of uses and meaning change, including the pragmatic strengthening of interpretations such as excessiveness (beh, necessity (ai, beh, proximity (beh and conditional (beh, and prediction of an undesirable future (ai.

  20. Resolving the controversy of the proportion validity effect: Volitional attention is not required, but may have an effect.

    Science.gov (United States)

    Lanthier, Sophie N; Wu, David W-L; Chapman, Craig S; Kingstone, Alan

    2015-11-01

    Response time (RT) is facilitated when a target appears at a cued (valid) location versus an uncued (invalid) location. Interestingly, this valid-versus-invalid RT difference increases as the percentage of valid trials increases. In the present study, we investigated the mechanism responsible for this proportion valid cueing effect (PVE). The PVE is thought to reflect changes in voluntary attentional allocation, with greater attention being committed endogenously to the cued location as the percentage of valid trials increases. However, recent research has suggested that the PVE may reflect a form of implicit learning between the cue and the target location that is developed outside of awareness, and that this determines how attention is allocated. This lack of convergence may be due to methodological differences in how voluntary processing has been inferred. To test this issue, we generated a method that would allow the measurement of different degrees of volitional attention. In addition, we manipulated whether participants were instructed to attend to the cue-target relationship and determined whether this explicit engagement of attention influenced the PVE. We found that for both peripheral and central cues, volitional control is not required for a PVE; however, volitional control can modulate a PVE that is produced by central cues. Thus, a PVE is not a reliable indicator of volitional control, but its sensitivity to volitional control varies across cues. The present data shed light on the mechanism subserving the PVE and lend support to the theory that different cues engage, to some degree, qualitatively different forms of visuospatial attention.

  1. Airbag induced facial and bilateral ocular injuries in a 14-year-old child

    Science.gov (United States)

    Alquraini, Talal A.; Aggour, Mustafa A.; Zamzam, Ahmed M.

    2010-01-01

    Although air bags have reduced the incidence of fatal and severe injuries in automobile collisions, they have been shown to carry a risk of injury themselves. Ocular injury in particular can often be a direct consequence of air bag deployment. We report a 14-year-old child who sustained facial burn and bilateral ocular injuries affecting both the anterior and posterior segments due to an inflated air bag in a low speed motor vehicle accident. PMID:23960958

  2. Ocular defects in cerebral palsy

    OpenAIRE

    Katoch Sabita; Devi Anjana; Kulkarni Prajakta

    2007-01-01

    There is a high prevalence of ocular defects in children with developmental disabilities. This study evaluated visual disability in a group of 200 cerebral palsy (CP) patients and found that 68% of the children had significant visual morbidity. These findings emphasize the need for an early ocular examination in patients with CP.

  3. Ocular defects in cerebral palsy

    Directory of Open Access Journals (Sweden)

    Katoch Sabita

    2007-01-01

    Full Text Available There is a high prevalence of ocular defects in children with developmental disabilities. This study evaluated visual disability in a group of 200 cerebral palsy (CP patients and found that 68% of the children had significant visual morbidity. These findings emphasize the need for an early ocular examination in patients with CP.

  4. Ocular defects in cerebral palsy.

    Science.gov (United States)

    Katoch, Sabita; Devi, Anjana; Kulkarni, Prajakta

    2007-01-01

    There is a high prevalence of ocular defects in children with developmental disabilities. This study evaluated visual disability in a group of 200 cerebral palsy (CP) patients and found that 68% of the children had significant visual morbidity. These findings emphasize the need for an early ocular examination in patients with CP.

  5. Ocular leech infestation

    Directory of Open Access Journals (Sweden)

    Lee YC

    2015-02-01

    Full Text Available Yueh-Chang Lee, Cheng-Jen Chiu Department of Ophthalmology, Buddhist Tzu-Chi General Hospital, Hualien, Taiwan, ROC Abstract: This case report describes a female toddler with manifestations of ocular leech infestation. A 2-year-old girl was brought to our outpatient clinic with a complaint of irritable crying after being taken to a stream in Hualien 1 day previous, where she played in the water. The parents noticed that she rubbed her right eye a lot. Upon examination, the girl had good fix and follow in either eye. Slit-lamp examination showed conjunctival injection with a moving dark black–brown foreign body partly attached in the lower conjunctiva. After applying topical anesthetics, the leech, measuring 1 cm in length, was extracted under a microscope. The patient began using topical antibiotic and corticosteroid agents. By 1 week after extraction, the patient had no obvious symptoms or signs, except for a limited subconjunctival hemorrhage, and no corneal/scleral involvement was observed. Keywords: leech, ocular foreign body, conjunctival reaction, pediatric ophthalmology

  6. Volitional Muscle Strength in the Legs Predicts Changes in Walking Speed Following Locomotor Training in People With Chronic Spinal Cord Injury

    Science.gov (United States)

    Norton, Jonathan; Nevett-Duchcherer, Jennifer; Roy, Francois D.; Gross, Douglas P.; Gorassini, Monica A.

    2011-01-01

    Background It is unclear which individuals with incomplete spinal cord injury best respond to body-weight–supported treadmill training. Objective The purpose of this study was to determine the factors that predict whether a person with motor incomplete spinal cord injury will respond to body-weight–supported treadmill training. Design This was a prognostic study with a one-group pretest-posttest design. Methods Demographic, clinical, and electrophysiological measurements taken prior to training were examined to determine which measures best predicted improvements in walking speed in 19 individuals with chronic (>7 months postinjury), motor-incomplete spinal cord injuries (ASIA Impairment Scale categories C and D, levels C1–L1). Results Two initial measures correlated significantly with improvements in walking speed: (1) the ability to volitionally contract a muscle, as measured by the lower-extremity manual muscle test (LE MMT) (r=.72), and (2) the peak locomotor electromyographic (EMG) amplitude in the legs (r=.56). None of the demographics (time since injury, age, body mass index) were significantly related to improvements in walking speed, nor was the clinical measure of balance (Berg Balance Scale). Further analysis of LE MMT scores showed 4 key muscle groups were significantly related to improvements in walking speed: knee extensors, knee flexors, ankle plantar flexors, and hip abductors (r=.82). Prediction using the summed MMT scores from those muscles and peak EMG amplitude in a multivariable regression indicated that peak locomotor EMG amplitude did not add significantly to the prediction provided by the LE MMT alone. Change in total LE MMT scores from the beginning to the end of training was not correlated with a change in walking speed over the same period. Limitations The sample size was limited, so the results should be considered exploratory. Conclusions The results suggest that preserved muscle strength in the legs after incomplete spinal cord

  7. Corticosteroids for ocular toxoplasmosis

    Science.gov (United States)

    Jasper, Smitha; Vedula, Satyanarayana S; John, Sheeja S; Horo, Saban; Sepah, Yasir J; Nguyen, Quan Dong

    2014-01-01

    Background Ocular infestation with Toxoplasma gondii, a parasite, may result in inflammation in the retina, choroid, and uvea and consequently lead to complications such as glaucoma, cataract, and posterior synechiae. Objectives The objective of this systematic review was to assess the effects of adjunctive use of corticosteroids for ocular toxoplasmosis. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 9), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE, (January 1950 to October 2012), EMBASE (January 1980 to October 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to October 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 searched the reference lists of included studies for any additional studies not identified by the electronic searches. We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 11 October 2012. Selection criteria We planned to include randomized and quasi-randomized controlled trials. Eligible trials would have enrolled participants of any age who were immunocompetent and were diagnosed with active ocular toxoplasmosis. Included trials would have compared anti-parasitic therapy plus corticosteroids versus anti-parasitic therapy alone, or different doses or times of initiation of corticosteroids. Data collection and analysis Two authors independently screened titles and abstracts retrieved from the electronic searches. We retrieved full-text articles of studies categorized as ‘unsure’ or ‘include’ after review of the abstracts. Two authors independently reviewed each full-text article. Discrepancies were

  8. Ocular Argyrosis Mimicking Conjunctival Melanoma.

    Science.gov (United States)

    Tendler, Irwin; Pulitzer, Melissa P; Roggli, Victor; Abramson, David H; Marr, Brian P

    2017-06-01

    To present a novel case of ocular argyrosis mimicking conjunctival melanoma. A 48-year-old man who is a jewelry manufacturer presented with raised pigmented lesions in the inferior fornices of both eyes. Brown-black colored, follicle-like, masses were observed in both fornices. An incisional biopsy confirmed the presence of silver and the diagnosis of ocular argyrosis. Despite its limited negative health effects, ocular argyrosis should be considered in the differential diagnosis of conjunctival pigmented lesions because of the potential for misidentification of neoplastic growth.

  9. Ocular Blood Flow Autoregulation Mechanisms and Methods

    Directory of Open Access Journals (Sweden)

    Xue Luo

    2015-01-01

    Full Text Available The main function of ocular blood flow is to supply sufficient oxygen and nutrients to the eye. Local blood vessels resistance regulates overall blood distribution to the eye and can vary rapidly over time depending on ocular need. Under normal conditions, the relation between blood flow and perfusion pressure in the eye is autoregulated. Basically, autoregulation is a capacity to maintain a relatively constant level of blood flow in the presence of changes in ocular perfusion pressure and varied metabolic demand. In addition, ocular blood flow dysregulation has been demonstrated as an independent risk factor to many ocular diseases. For instance, ocular perfusion pressure plays key role in the progression of retinopathy such as glaucoma and diabetic retinopathy. In this review, different direct and indirect techniques to measure ocular blood flow and the effect of myogenic and neurogenic mechanisms on ocular blood flow are discussed. Moreover, ocular blood flow regulation in ocular disease will be described.

  10. Volitional Weight-Lifting in Rats Promotes Adaptation via Performance and Muscle Morphology prior to Gains in Muscle Mass

    OpenAIRE

    Rader, Erik P.; G. Roger Miller; Chetlin, Robert D.; Oliver Wirth; Baker, Brent A.

    2014-01-01

    Investigation of volitional animal models of resistance training has been instrumental in our understanding of adaptive training. However, these studies have lacked reactive force measurements, a precise performance measure, and morphological analysis at a distinct phase of training – when initial strength gains precede muscle hypertrophy. Our aim was to expose rats to one month of training (70 or 700 g load) on a custom-designed weight-lifting apparatus for analysis of reactive forces and mu...

  11. Volitional regulation of emotions produces distributed alterations in connectivity between visual, attention control, and default networks.

    Science.gov (United States)

    Sripada, Chandra; Angstadt, Michael; Kessler, Daniel; Phan, K Luan; Liberzon, Israel; Evans, Gary W; Welsh, Robert C; Kim, Pilyoung; Swain, James E

    2014-04-01

    The ability to volitionally regulate emotions is critical to health and well-being. While patterns of neural activation during emotion regulation have been well characterized, patterns of connectivity between regions remain less explored. It is increasingly recognized that the human brain is organized into large-scale intrinsic connectivity networks (ICNs) whose interrelationships are altered in characteristic ways during psychological tasks. In this fMRI study of 54 healthy individuals, we investigated alterations in connectivity within and between ICNs produced by the emotion regulation strategy of reappraisal. In order to gain a comprehensive picture of connectivity changes, we utilized connectomic psychophysiological interactions (PPI), a whole-brain generalization of standard single-seed PPI methods. In particular, we quantified PPI connectivity pair-wise across 837 ROIs placed throughout the cortex. We found that compared to maintaining one's emotional responses, engaging in reappraisal produced robust and distributed alterations in functional connections involving visual, dorsal attention, frontoparietal, and default networks. Visual network in particular increased connectivity with multiple ICNs including dorsal attention and default networks. We interpret these findings in terms of the role of these networks in mediating critical constituent processes in emotion regulation, including visual processing, stimulus salience, attention control, and interpretation and contextualization of stimuli. Our results add a new network perspective to our understanding of the neural underpinnings of emotion regulation, and highlight that connectomic methods can play a valuable role in comprehensively investigating modulation of connectivity across task conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. [Emotional-volitional training in the combined treatment of patients with rheumatoid arthritis].

    Science.gov (United States)

    Siniachenko, V V; Leshchenko, G Ia; Melekhin, V D

    1990-01-01

    The development of placebo effect was found to be related to the psychological status and neurophysiological features of the body. This made it possible to elaborate the disadaptation hypothesis of the disease development and a total systems approach to its treatment, characterized by the necessity of conducting both conventional (aimed at suppression of the autoimmune process and inflammation) and activation therapy. The method of emotional volitional training (EVT) designed by the authors is advanced as one of the components of the activation therapy lying in the use of music therapy, auto- and heteropsychic actions together with application of an optimal variety of group physical training. Application of the EVT to the treatment of 86 patients with rheumatoid arthritis enabled the drug dosage to be reduced by as many as 50%, to improve the patients' mental status and to enhance work fitness, promoting the decrease of the hospital treatment by 4-5 days and prolongation of the remission from 6 months to 1.5 years.

  13. Pathological gambling and obsessive-compulsive disorder: towards a spectrum of disorders of volition.

    Science.gov (United States)

    Tavares, Hermano; Gentil, Valentim

    2007-06-01

    Pathological gambling is proposed as a participant of an impulsive-compulsive spectrum related to obsessive-compulsive disorder. This study aims to contrast pathological gambling and obsessive-compulsive disorder regarding course, comorbidity, and personality, hence testing the validity of the impulsive-compulsive spectrum. 40 pathological gambling and 40 obsessive-compulsive disorder subjects matched to 40 healthy volunteers according to gender, age, and education were assessed with the Temperament Personality Questionnaire and the Barratt Impulsiveness Scale. Psychiatric patients were also assessed for course and comorbidity data. Obsessive-compulsive disorder presented an earlier onset, but the full syndrome took longer to evolve. Pathological gambling had higher comorbidity with substance-related disorders, and obsessive-compulsive disorder higher comorbidity with somatoform disorders. Gamblers scored higher than controls on the sub-factors Impulsiveness, Extravagance, Disorderliness, and Fear of Uncertainty. Obsessive-compulsive patients scored higher than controls on Fear of Uncertainty. Impulsiveness, Extravagance, and Disorderliness significantly correlated with the Barratt Impulsiveness Scale total score, Fear of Uncertainty did not. The course and comorbidity profiles of pathological gambling resemble an addiction and differ from obsessive-compulsive disorder. Pathological gambling combines impulsive and compulsive traits. Impulsivity and compulsivity should be regarded as orthogonal constructs, and as drives implicated in volition aspects of behavioral syndromes.

  14. Ocular tropism of respiratory viruses.

    Science.gov (United States)

    Belser, Jessica A; Rota, Paul A; Tumpey, Terrence M

    2013-03-01

    Respiratory viruses (including adenovirus, influenza virus, respiratory syncytial virus, coronavirus, and rhinovirus) cause a broad spectrum of disease in humans, ranging from mild influenza-like symptoms to acute respiratory failure. While species D adenoviruses and subtype H7 influenza viruses are known to possess an ocular tropism, documented human ocular disease has been reported following infection with all principal respiratory viruses. In this review, we describe the anatomical proximity and cellular receptor distribution between ocular and respiratory tissues. All major respiratory viruses and their association with human ocular disease are discussed. Research utilizing in vitro and in vivo models to study the ability of respiratory viruses to use the eye as a portal of entry as well as a primary site of virus replication is highlighted. Identification of shared receptor-binding preferences, host responses, and laboratory modeling protocols among these viruses provides a needed bridge between clinical and laboratory studies of virus tropism.

  15. The Ocular Surface Chemical Burns

    OpenAIRE

    Medi Eslani; Alireza Baradaran-Rafii; Asadolah Movahedan; Djalilian, Ali R.

    2014-01-01

    Ocular chemical burns are common and serious ocular emergencies that require immediate and intensive evaluation and care. The victims of such incidents are usually young, and therefore loss of vision and disfigurement could dramatically affect their lives. The clinical course can be divided into immediate, acute, early, and late reparative phases. The degree of limbal, corneal, and conjunctival involvement at the time of injury is critically associated with prognosis. The treatment starts wit...

  16. Trauma ocular y politrauma Ocular trauma and multitrauma

    Directory of Open Access Journals (Sweden)

    Dunia Cruz Izquierdo

    2012-01-01

    Full Text Available Se realizó una revisión sobre el trauma ocular y su manejo en pacientes politraumatizados. Entre las causas más frecuentes de trauma ocular se encuentran los accidentes domésticos, laborales, juegos, actividades recreativas y deportivas. Involucran en un alto por ciento a niños y jóvenes, y predomina el sexo masculino en casi todos los trabajos revisados. No solo en Cuba sino en el mundo, el trauma ocular es fuente importante de ceguera unilateral o bilateral. Se presenta un breve compendio de los términos y definiciones actuales que son utilizados para el manejo del trauma ocular, su clasificación y la ventaja que ofrece aplicar el Puntaje del Trauma Ocular, OTS (Ocular Trauma Score, para el pronóstico de la agudeza visual final de acuerdo a los hallazgos clínicos encontrados en la evaluación inicial. Se hace referencia a los pacientes con politrauma y los aspectos a tener en cuenta por el oftalmólogo para tomar conducta cuando estos presentan heridas penetrantes o perforantes y tienen compromiso vital. En estos casos se hace necesaria la colaboración urgente de múltiples especialistas para primero mantener al paciente con vida y luego disminuir las complicaciones que repercuten en su pronóstico visual.A review was made on the ocular trauma and its management in multitrauma patients. The most common causes comprise domestic and occupational accidents, games, recreational and sport activities. It involves more frequently a high percentage of young people, with male prevalence in almost all the reviewed papers. Ocular trauma is an important source of unilateral or bilateral blindness not only in Cuba but worldwide as well. A brief summary of the current terms and definitions used to manage ocular trauma, their classification and the advantage of the Ocular Trauma Score (OTS to know the possible final visual acuity, according to the clinical findings at the emergency room, were presented. Reference was also made to the multitrauma

  17. Callosal Motor Impersistence: A Novel Disconnection Syndrome.

    Science.gov (United States)

    Kim, Hee Jin; Kim, Dongyeop; Won, Da-Heen; Chin, Juhee; Lee, Kwang Ho; Seo, Sang Won; Heilman, Kenneth M; Na, Duk L

    2017-06-01

    Motor impersistence, an inability to sustain a certain position or movement, is a motor-intentional disorder, caused more often by right than left hemisphere lesions. Since the right hemisphere is dominant for mediating motor persistence, callosal lesions that disconnect the left hemisphere from the right may induce impersistence of the right upper and lower limbs. After an undiagnosed left callosal infarction, a 65-year-old right-handed man suddenly developed a transient loss of volitional movement of his left leg. Five days after onset, he was admitted to our hospital with signs of callosal disconnection: left-hand agraphia and apraxia, left-hand tactile anomia, failures on cross-replication of hand postures, and intermanual conflict. He had neither weakness nor ataxia of his upper or lower extremities, but when asked to keep his arms or legs extended he could not maintain his right arm and leg in the extended position, suggesting motor impersistence in his dominant limbs. When we examined him 3 months after onset, the motor impersistence had disappeared. In conclusion, motor impersistence of dominant limbs can result from isolated callosal injury that disconnects the left hemisphere from the right hemisphere's frontal-subcortical networks.

  18. Ocular allergy latin american consensus

    Directory of Open Access Journals (Sweden)

    Myrna Serapião dos Santos

    2011-12-01

    Full Text Available PURPOSE: To establish current definition, classification and staging, and to develop diagnosis and treatment recommendations for ocular allergy, by using Delphi approach. METHODS: Ten Latin American experts on ocular allergy participated in a 4-round Delphi panel approach. Four surveys were constructed and answered by panelists. A two-thirds majority was defined as consensus. Definition, classification, staging and diagnosis and treatment recommendations were the main outcomes. RESULTS: "Ocular allergy" was proposed as the general term to describe ocular allergic diseases. Consensus regarding classification was not reached. Signs and symptoms were considered extremely important for the diagnosis. It was consensus that a staging system should be proposed based on the disease severity. Environmental control, avoidance of allergens and the use of artificial tears were recommended as first line treatment. The secondary treatment should include topical anti-histamines, mast cell stabilizers and multi actions drugs. Topical non-steroidal anti-inflammatory and vasoconstrictors were not recommended. Topical corticosteroids were recommended as third line of treatment for the most severe keratoconjunctivitis. Consensus was not reached regarding the use of systemic corticosteroids or immunosuppressant. Surgical approach and unconventional treatments were not recommended as routine. CONCLUSION: The task of creating guidelines for ocular allergies showed to be very complex. Many controversial topics remain unsolved. A larger consensus including experts from different groups around the world may be needed to further improve the current recommendations for several aspects of ocular allergy.

  19. Ocular injuries from paintball pellets.

    Science.gov (United States)

    Thach, A B; Ward, T P; Hollifield, R D; Dugel, P U; Sipperley, J O; Marx, J L; Abrams, D A; Wroblewski, K J; Sonkin, P L; Birdsong, R H; Dunlap, W A

    1999-03-01

    To evaluate the ocular effects of blunt trauma due to injury from a paintball pellet. Noncomparative case series. Thirteen patients who suffered ocular injury from paintballs are described. The patients presented to six different civilian and military emergency departments in tertiary care medical centers. Patients were treated for the ocular injury. Patients were evaluated for initial and final visual acuity. The reason for persistent loss of vision was delineated. There were 12 males and 1 female with an average age of 21 years (range, 12-33 years). Eleven of the 13 had no ocular protection at the time of the ocular injury. On initial examination, nine patients had a hyphema, nine had a vitreous hemorrhage, six had a retinal tear or detachment, three had corneal or corneal-scleral ruptures, and one had traumatic optic neuropathy. The final visual acuity was 20/40 or better in two patients, 20/50 to 20/150 in three patients, and 20/200 or worse in eight patients. Injuries due to paintball pellets can result in severe ocular damage and significant loss of vision. Eyecare professionals should be aware of the risks of this sport and must strongly advise participants to wear adequate protection when involved in this activity.

  20. Motor Neurons

    DEFF Research Database (Denmark)

    Hounsgaard, Jorn

    2017-01-01

    Motor neurons translate synaptic input from widely distributed premotor networks into patterns of action potentials that orchestrate motor unit force and motor behavior. Intercalated between the CNS and muscles, motor neurons add to and adjust the final motor command. The identity and functional...

  1. A functional and structural investigation of the human fronto-basal volitional saccade network.

    Directory of Open Access Journals (Sweden)

    Sebastiaan F W Neggers

    Full Text Available Almost all cortical areas are connected to the subcortical basal ganglia (BG through parallel recurrent inhibitory and excitatory loops, exerting volitional control over automatic behavior. As this model is largely based on non-human primate research, we used high resolution functional MRI and diffusion tensor imaging (DTI to investigate the functional and structural organization of the human (prefrontal cortico-basal network controlling eye movements. Participants performed saccades in darkness, pro- and antisaccades and observed stimuli during fixation. We observed several bilateral functional subdivisions along the precentral sulcus around the human frontal eye fields (FEF: a medial and lateral zone activating for saccades in darkness, a more fronto-medial zone preferentially active for ipsilateral antisaccades, and a large anterior strip along the precentral sulcus activating for visual stimulus presentation during fixation. The supplementary eye fields (SEF were identified along the medial wall containing all aforementioned functions. In the striatum, the BG area receiving almost all cortical input, all saccade related activation was observed in the putamen, previously considered a skeletomotor striatal subdivision. Activation elicited by the cue instructing pro or antisaccade trials was clearest in the medial FEF and right putamen. DTI fiber tracking revealed that the subdivisions of the human FEF complex are mainly connected to the putamen, in agreement with the fMRI findings. The present findings demonstrate that the human FEF has functional subdivisions somewhat comparable to non-human primates. However, the connections to and activation in the human striatum preferentially involve the putamen, not the caudate nucleus as is reported for monkeys. This could imply that fronto-striatal projections for the oculomotor system are fundamentally different between humans and monkeys. Alternatively, there could be a bias in published reports of

  2. Purinergic Receptors in Ocular Inflammation

    Directory of Open Access Journals (Sweden)

    Ana Guzman-Aranguez

    2014-01-01

    Full Text Available Inflammation is a complex process that implies the interaction between cells and molecular mediators, which, when not properly “tuned,” can lead to disease. When inflammation affects the eye, it can produce severe disorders affecting the superficial and internal parts of the visual organ. The nucleoside adenosine and nucleotides including adenine mononucleotides like ADP and ATP and dinucleotides such as P1,P4-diadenosine tetraphosphate (Ap4A, and P1,P5-diadenosine pentaphosphate (Ap5A are present in different ocular locations and therefore they may contribute/modulate inflammatory processes. Adenosine receptors, in particular A2A adenosine receptors, present anti-inflammatory action in acute and chronic retinal inflammation. Regarding the A3 receptor, selective agonists like N6-(3-iodobenzyl-5′-N-methylcarboxamidoadenosine (CF101 have been used for the treatment of inflammatory ophthalmic diseases such as dry eye and uveoretinitis. Sideways, diverse stimuli (sensory stimulation, large intraocular pressure increases can produce a release of ATP from ocular sensory innervation or after injury to ocular tissues. Then, ATP will activate purinergic P2 receptors present in sensory nerve endings, the iris, the ciliary body, or other tissues surrounding the anterior chamber of the eye to produce uveitis/endophthalmitis. In summary, adenosine and nucleotides can activate receptors in ocular structures susceptible to suffer from inflammatory processes. This involvement suggests the possible use of purinergic agonists and antagonists as therapeutic targets for ocular inflammation.

  3. The ocular surface chemical burns.

    Science.gov (United States)

    Eslani, Medi; Baradaran-Rafii, Alireza; Movahedan, Asadolah; Djalilian, Ali R

    2014-01-01

    Ocular chemical burns are common and serious ocular emergencies that require immediate and intensive evaluation and care. The victims of such incidents are usually young, and therefore loss of vision and disfigurement could dramatically affect their lives. The clinical course can be divided into immediate, acute, early, and late reparative phases. The degree of limbal, corneal, and conjunctival involvement at the time of injury is critically associated with prognosis. The treatment starts with simple but vision saving steps and is continued with complicated surgical procedures later in the course of the disease. The goal of treatment is to restore the normal ocular surface anatomy and function. Limbal stem cell transplantation, amniotic membrane transplantation, and ultimately keratoprosthesis may be indicated depending on the patients' needs.

  4. The Ocular Surface Chemical Burns

    Directory of Open Access Journals (Sweden)

    Medi Eslani

    2014-01-01

    Full Text Available Ocular chemical burns are common and serious ocular emergencies that require immediate and intensive evaluation and care. The victims of such incidents are usually young, and therefore loss of vision and disfigurement could dramatically affect their lives. The clinical course can be divided into immediate, acute, early, and late reparative phases. The degree of limbal, corneal, and conjunctival involvement at the time of injury is critically associated with prognosis. The treatment starts with simple but vision saving steps and is continued with complicated surgical procedures later in the course of the disease. The goal of treatment is to restore the normal ocular surface anatomy and function. Limbal stem cell transplantation, amniotic membrane transplantation, and ultimately keratoprosthesis may be indicated depending on the patients’ needs.

  5. [Ocular Behçet].

    Science.gov (United States)

    Alami, Ahmed; Kriet, Mohamed; Reda, Karim; Laktaoui, Abdelkader; Oubaaz, Abdelbaare

    2017-01-01

    Our study aimed to determine the clinical, therapeutic and prognostic features of ocular involvement in patients with Behçet's disease treated in our Department of ophthalmology. We conducted a retrospective data collection from medical records of 20 patients treated at the military hospital in Laayoune. All patients underwent complete ophthalmological examination and fluorescein angiography if necessary. OCT exam was performed in two patients. Ten patients had anterior uveitis, complicated in one case by ocular hypertonia; two patients had intermediate uveitis; eight patients had posterior segment involvement complicated in one case by intravitreal hemorrhage. Behcet's Disease (BD) is an systemic idiopathic inflammatory disease currently classified within primary non-necrotizing vasculitis. Ocular involvement is common and severe in Behçet's disease, with the potential to compromise the visual prognosis. Behcet's disease is common in Morocco. It can compromise patient's visual prognosis making the collaboration between ophthalmologists and internists particularly important.

  6. [Ultrasonographic findings in ocular toxocariasis].

    Science.gov (United States)

    Morais, Fábio Barreto; Maciel, Ana Lúcia; Arantes, Tiago Eugênio Farias e; Muccioli, Cristina; Allemann, Norma

    2012-01-01

    To evaluate ophthalmic ultrasound findings in the three presentation forms of ocular toxocariasis (peripheral or posterior pole granulomas and chronic endophthalmitis), in patients with confirmed diagnosis of ocular toxocariasis. 11 patients (11 eyes) with clinical and confirmed diagnosis of active ocular toxocariasis, presented positive ELISA test, were analyzed, prospectively, in the study. The patients were submitted to an ocular ultrasound examination (10-MHz transducer, contact technique). In the series of 11 patients, mean age was 7.9 years-old (range from 2 to 17 y), 73% male, referring previous contact with dogs (91%), and with the soil (50%), no referral of appetite perversion. In the analyses of compromised eyes (11 eyes), the ophthalmoscopic examination revealed the following distribution of the 3 forms of ocular toxocariasis: 7 cases (63.6%), posterior pole granuloma; 1 (9.1%), chronic endophthalmitis; 2 (18.2%), peripheral granuloma; and 1 (9.1%), posterior pole granuloma associated with chronic endophthalmitis. Visual acuity impairment: no light perception (3 eyes, 27.3%); hand motion (4 eyes, 36.4%); counting fingers at 10 cm (1 eye, 9.1%); 20/200 (1 eye, 9.1%); 20/70 (1 eye, 9.1%); undefined (1 eye, 9.1%). Serology was positive to Toxocara canis (ELISA test) in 100% of the cases. Ophthalmoscopy was difficult or impossible in 64% of the cases due to the media opacity. Ultrasound findings noted were vitreous membranes with retinal attachment (100%); parietal lesions (granulomas) with high (80%) or medium (20%) reflectivity. The most consistent ultrasound finding in the eye with toxocariasis was a high-reflectivity retinal mass, located in posterior pole or periphery, which may be calcified, and which has as main characteristic the adherence of vitreous membranes. In addition to clinical history, systemic evaluation and serology, the ultrasound can help in the diagnosis of ocular toxocariasis, especially in media opacities.

  7. DIAGNOSIS OF EMOTIONAL AND VOLITIONAL SELF-REGULATION OF PRIMARY SCHOOL AGED PUPILS’ IN TERMS OF THE VOCAL AND CHORAL ACTIVITIES

    Directory of Open Access Journals (Sweden)

    Olga A. Malakhova

    2015-01-01

    Full Text Available The aim of the study is to investigate emotional and volitional self-regulation of primary school children during musical activities such as a choral performance.Methods. The proposed method of diagnosing emotional and volitional selfregulation in the process of choral activities, and methods of mathematical statistics are applied. Results and scientific novelty. The author formulates the definition of emotional and volitional self-regulation; criteria and indicators for its diagnosis are developed. The main criteria for the development of emotional and volitional selfregulation are: «self-control in the process of hearing musical performance», «emotional performance of a musical work», and «arbitrary regulation of psychophysiological state». The data obtained in the course of diagnosis in the Ural College of Music in vocal and choral activities at primary school children are analyzed. The use of mathematical statistics to summarize the data is justified.Practical significance. The development techniques of emotional and volitional self-regulation of future musicians to choral exercises are described; this technology may be used in music colleges, children’s art schools, as well as the highest level of musical performing and musical-pedagogical education. Research materials can be useful both to psychologists, and experts in the field of music education.

  8. Ocular manifestation in canine leishmaniasis

    Directory of Open Access Journals (Sweden)

    Ralić Marjan

    2011-01-01

    Full Text Available This paper presents a case of ocular changes in leishmaniasis in a dog brought in for examination because of visible changes in the eyes. An ocular manifestation in leishmaniasis can be bilateral or unilateral. Changes most often occur on the conjunctive and the front segment of the eye, the cornea and iris. From 70 to 80% of dogs diseased with leishmaniasis exhibit frontal uveitis, and dry eye, keratoconjunctivitis sicca, is also a frequent finding. Based on the clinical picture and the positive immunochromatographic rapid test it was established that the dog was diseased with leishmaniasis.

  9. [Adverse ocular effects of vaccinations].

    Science.gov (United States)

    Ness, T; Hengel, H

    2016-07-01

    Vaccinations are very effective measures for prevention of infections but are also associated with a long list of possible side effects. Adverse ocular effects following vaccination have been rarely reported or considered to be related to vaccinations. Conjunctivitis is a frequent sequel of various vaccinations. Oculorespiratory syndrome and serum sickness syndrome are considered to be related to influenza vaccinations. The risk of reactivation or initiation of autoimmune diseases (e. g. uveitis) cannot be excluded but has not yet been proven. Overall the benefit of vaccination outweighs the possible but very low risk of ocular side effects.

  10. Tumor ocular metastásico Metastatic ocular tumor

    Directory of Open Access Journals (Sweden)

    Martha G Domínguez Expósito

    2004-06-01

    Full Text Available El carcinoma metastásico del ojo es considerado la neoplasia maligna que más frecuente se encuentra de forma intraocular. Solo cerca del 10 % de las personas que tienen una o más lesiones metastásicas intraoculares son detectadas clínicamente antes de la muerte. A menudo, el carcinoma metastásico ocular es diagnosticado por el oftalmólogo ante la presencia de síntomas oculares. Las lesiones están localizadas con preferencia en coroides. Nos motivo a realizar la presentación de este caso la presencia de lesiones intraoculares múltiples tumorales metastásicos en un paciente cuyo síntoma de presentación fue la disminución de la agudeza visualThe eye metastatic carcinoma is considered the most frequently found intraocular malignant neoplasia. Only 10 % of the persons with one or more metastatic intraocular injuries are clinically detected before death. The metastatic ocular carcinoma is often diagnosed by the ophthalmologist in the presence of ocular symptoms. The injuries are preferably located in the choroid. The appearance of multiple metastatic intraaocular tumoral injuries in a patient whose chief complaint was the reduction of visual acuity motivated us to presente this case

  11. Sonographic measurements of ocular biometry of indigenous ...

    African Journals Online (AJOL)

    Sonographic measurements of ocular biometry of indigenous Nigerian dogs in Zaria, Nigeria. ... The dogs were adequately restrained physically and the structure of the ocular globe was evaluated at a depth of 4-6 cm. For each dog ... Keywords: Ultrasonography, Baseline Value, Nigerian indigenous Dog, Ocular Biometry ...

  12. The Relationship Between Ocular Itch, Ocular Pain, and Dry Eye Symptoms (An American Ophthalmological Society Thesis).

    Science.gov (United States)

    Galor, Anat; Small, Leslie; Feuer, William; Levitt, Roy C; Sarantopoulos, Konstantinos D; Yosipovitch, Gil

    2017-08-01

    To evaluate associations between sensations of ocular itch and dry eye (DE) symptoms, including ocular pain, and DE signs. A cross-sectional study of 324 patients seen in the Miami Veterans Affairs eye clinic was performed. The evaluation consisted of questionnaires regarding ocular itch, DE symptoms, descriptors of neuropathic-like ocular pain (NOP), and evoked pain sensitivity testing on the forehead and forearm, followed by a comprehensive ocular surface examination including corneal mechanical sensitivity testing. Analyses were performed to examine for differences between those with and without subjective complaints of ocular itch. The mean age was 62 years with 92% being male. Symptoms of DE and NOP were more frequent in patients with moderate-severe ocular itch compared to those with no or mild ocular itch symptoms. With the exception of ocular surface inflammation (abnormal matrix metalloproteinase 9 testing) which was less common in those with moderate-severe ocular itch symptoms, DE signs were not related to ocular itch. Individuals with moderate-severe ocular itch also demonstrated greater sensitivity to evoked pain on the forearm and had higher non-ocular pain, depression, and post-traumatic stress disorders scores, compared to those with no or mild itch symptoms. Subjects with moderate-severe ocular itch symptoms have more severe symptoms of DE, NOP, non-ocular pain and demonstrate abnormal somatosensory testing in the form of increased sensitivity to evoked pain at a site remote from the eye, consistent with generalized hypersensitivity.

  13. Ultraviolet light and ocular diseases.

    Science.gov (United States)

    Yam, Jason C S; Kwok, Alvin K H

    2014-04-01

    The objective of this study is to review the association between ultraviolet (UV) light and ocular diseases. The data are sourced from the literature search of Medline up to Nov 2012, and the extracted data from original articles, review papers, and book chapters were reviewed. There is a strong evidence that ultraviolet radiation (UVR) exposure is associated with the formation of eyelid malignancies [basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)], photokeratitis, climatic droplet keratopathy (CDK), pterygium, and cortical cataract. However, the evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, ocular surface squamous neoplasia (OSSN), and ocular melanoma remained limited. There is insufficient evidence to determine whether age-related macular degeneration (AMD) is related to UV exposure. It is now suggested that AMD is probably related to visible radiation especially blue light, rather than UV exposure. From the results, it was concluded that eyelid malignancies (BCC and SCC), photokeratitis, CDK, pterygium, and cortical cataract are strongly associated with UVR exposure. Evidence of the association between UV exposure and development of pinguecula, nuclear and posterior subcapsular cataract, OSSN, and ocular melanoma remained limited. There is insufficient evidence to determine whether AMD is related to UV exposure. Simple behaviural changes, appropriate clothing, wearing hats, and UV blocking spectacles, sunglasses or contact lens are effective measures for UV protection.

  14. Ocular Vestibular Evoked Myogenic Potentials

    Directory of Open Access Journals (Sweden)

    Felipe, Lilian

    2014-01-01

    Full Text Available Introduction Diagnostic testing of the vestibular system is an essential component of treating patients with balance dysfunction. Until recently, testing methods primarily evaluated the integrity of the horizontal semicircular canal, which is only a portion of the vestibular system. Recent advances in technology have afforded clinicians the ability to assess otolith function through vestibular evoked myogenic potential (VEMP testing. VEMP testing from the inferior extraocular muscles of the eye has been the subject of interest of recent research. Objective To summarize recent developments in ocular VEMP testing. Results Recent studies suggest that the ocular VEMP is produced by otolith afferents in the superior division of the vestibular nerve. The ocular VEMP is a short latency potential, composed of extraocular myogenic responses activated by sound stimulation and registered by surface electromyography via ipsilateral otolithic and contralateral extraocular muscle activation. The inferior oblique muscle is the most superficial of the six extraocular muscles responsible for eye movement. Therefore, measurement of ocular VEMPs can be performed easily by using surface electrodes on the skin below the eyes contralateral to the stimulated side. Conclusion This new variation of the VEMP procedure may supplement conventional testing in difficult to test populations. It may also be possible to use this technique to evaluate previously inaccessible information on the vestibular system.

  15. Ocular Toxoplasmosis: Lessons from Brazil

    Science.gov (United States)

    • A new attention to post-natally acquired infections. Previously, most attention was focused on infection during pregnancy, and the risk of congenital disease, with the feeling that infection in older individuals was benign, without a substantial risk of disease morbidity, such as ocular involvemen...

  16. Ocular complications of malaria treatment

    African Journals Online (AJOL)

    2011-10-08

    Oct 8, 2011 ... Malaria is endemic in Nigeria. With the emergence of chloroquine resistance various modes of treatment including parenteral quinine are employed with consequent untoward effects. This article reports two cases of severe ocular toxicity, including mimicry of intracranial space-occupying lesion, from ...

  17. Lymphomatoid granulomatosis with ocular involvement.

    Science.gov (United States)

    Tse, D T; Mandelbaum, S; Chuck, D A; Nichols, P W; Smith, R E

    1985-01-01

    Lymphomatoid granulomatosis is an angiocentric and angiodestructive lymphoproliferative disorder that involves multiple organs including the lung, skin, kidney and central nervous system. A case of lymphomatoid granulomatosis with ocular involvement is reported herein. Bilateral peripheral retinal vasculitis involving both arterioles and veins, with posterior uveitis, is the prominent clinical finding.

  18. [Role of ocular pulse amplitude in glaucoma].

    Science.gov (United States)

    Stürmer, J P E; Kniestedt, C

    2015-02-01

    The ocular pulse amplitude is defined as the difference between diastolic and systolic intraocular pressure. The ocular pulse is generated by the pulsatile ocular blood flow in the choroid. It is dependent on the dynamics of the cardiovascular system, the rigidity of the ocular vessels on one side and the biomechanical properties of the eye on the other side. In addition the influence of outflow facility of the aqueous humor, the level of the intraocular pressure itself and last but not least the rigidity of the sclera on the ocular pulse amplitude is until now not clear. Dynamic contour tonometry (Pascal®) does not only measure intraocular pressure almost independent of corneal thickness and curvature but also allows easy and fast measurement of ocular pulse amplitude on the slit lamp. The ocular pulse amplitude in healthy subjects is between 1.2 and 4 mmHg. If the ocular pulse amplitude is larger than 1.2 mmHg spontaneous pulsations of the central retinal vein are visible on fundoscopy. In patients with ocular hypertension the ocular pulse amplitude is larger than in normal subjects but this is mainly due to higher IOP levels. In patients with manifest open-angle glaucoma the ocular pulse amplitude stays initially within the normal range. In more advanced stages of the disease and especially in patients with ocular perfusion pressure dependent optic neuropathy the ocular pulse amplitude is gradually reduced. Due to the various factors influencing ocular pulse amplitude a direct correlation between reduced ocular pulse amplitude and reduced ocular perfusion pressure has not been established as yet. New approaches investigating the variations of the ocular pressure Fourier spectral analysis are promising, especially when simultaneous analysis of the arterial blood pressure is performed. These techniques may allow a fast and easy discrimination between healthy and glaucomatous patients in the near future. If ocular pulse amplitude exhibits a massive inter-ocular

  19. Understanding the Adoption Process of National Security Technology: An Integration of Diffusion of Innovations and Volitional Behavior Theories.

    Science.gov (United States)

    Iles, Irina A; Egnoto, Michael J; Fisher Liu, Brooke; Ackerman, Gary; Roberts, Holly; Smith, Daniel

    2017-11-01

    After the 9/11 terrorist attacks, the U.S. government initiated several national security technology adoption programs. The American public, however, has been skeptical about these initiatives and adoption of national security technologies has been mandated, rather than voluntary. We propose and test a voluntary behavioral intention formation model for the adoption of one type of new security technology: portable radiation detectors. Portable radiation detectors are an efficient way of detecting radiological and nuclear threats and could potentially prevent loss of life and damage to individuals' health. However, their functioning requires that a critical mass of individuals use them on a daily basis. We combine the explanatory advantages of diffusion of innovation with the predictive power of two volitional behavior frameworks: the theory of reasoned action and the health belief model. A large sample survey (N = 1,482) investigated the influence of factors identified in previous diffusion of innovation research on portable radiation detector adoption intention. Results indicated that nonfinancial incentives, as opposed to financial incentives, should be emphasized in persuasive communications aimed at fostering adoption. The research provides a new integration of diffusion of innovation elements with determinants of volitional behavior from persuasion literature, and offers recommendations on effective communication about new security technologies to motivate public adoption and enhance national safety. © 2017 Society for Risk Analysis.

  20. Central ocular motor disorders, including gaze palsy and nystagmus

    OpenAIRE

    Strupp, M.; Kremmyda, O.; Adamczyk, C.; N. Böttcher; Muth, C.; Yip, C. W.; Bremova, T.

    2014-01-01

    An impairment of eye movements, or nystagmus, is seen in many diseases of the central nervous system, in particular those affecting the brainstem and cerebellum, as well as in those of the vestibular system. The key to diagnosis is a systematic clinical examination of the different types of eye movements, including: eye position, range of eye movements, smooth pursuit, saccades, gaze-holding function and optokinetic nystagmus, as well as testing for the different types of nystagmus (e.g., cen...

  1. Motor Music

    OpenAIRE

    Richards, John

    2014-01-01

    Motor Music II (2014) for small group and motors What happens when an AC or DC motor is plugged raw into a mixing desk or connected directly to a speaker? Motor Music II explores ‘low level’ instrument design and a reductionist approach. The piece also sets up a proposition concerning electronic music: ‘How can it be done simpler?’ The motor as ‘instrument’ encourages an objection-orientated approach to sound and music making: the motor itself has inherent musical qualities and po...

  2. Targeting Lumbar Spinal Neural Circuitry by Epidural Stimulation to Restore Motor Function After Spinal Cord Injury.

    Science.gov (United States)

    Minassian, Karen; McKay, W Barry; Binder, Heinrich; Hofstoetter, Ursula S

    2016-04-01

    Epidural spinal cord stimulation has a long history of application for improving motor control in spinal cord injury. This review focuses on its resurgence following the progress made in understanding the underlying neurophysiological mechanisms and on recent reports of its augmentative effects upon otherwise subfunctional volitional motor control. Early work revealed that the spinal circuitry involved in lower-limb motor control can be accessed by stimulating through electrodes placed epidurally over the posterior aspect of the lumbar spinal cord below a paralyzing injury. Current understanding is that such stimulation activates large-to-medium-diameter sensory fibers within the posterior roots. Those fibers then trans-synaptically activate various spinal reflex circuits and plurisegmentally organized interneuronal networks that control more complex contraction and relaxation patterns involving multiple muscles. The induced change in responsiveness of this spinal motor circuitry to any residual supraspinal input via clinically silent translesional neural connections that have survived the injury may be a likely explanation for rudimentary volitional control enabled by epidural stimulation in otherwise paralyzed muscles. Technological developments that allow dynamic control of stimulation parameters and the potential for activity-dependent beneficial plasticity may further unveil the remarkable capacity of spinal motor processing that remains even after severe spinal cord injuries.

  3. Interfacial phenomena and the ocular surface.

    Science.gov (United States)

    Yañez-Soto, Bernardo; Mannis, Mark J; Schwab, Ivan R; Li, Jennifer Y; Leonard, Brian C; Abbott, Nicholas L; Murphy, Christopher J

    2014-07-01

    Ocular surface disorders, such as dry eye disease, ocular rosacea, and allergic conjunctivitis, are a heterogeneous group of diseases that require an interdisciplinary approach to establish underlying causes and develop effective therapeutic strategies. These diverse disorders share a common thread in that they involve direct changes in ocular surface chemistry as well as the rheological properties of the tear film and topographical attributes of the cellular elements of the ocular surface. Knowledge of these properties is crucial to understand the formation and stability of the preocular tear film. The study of interfacial phenomena of the ocular surface flourished during the 1970s and 1980s, but after a series of lively debates in the literature concerning distinctions between the epithelial and the glandular origin of ocular surface disorders during the 1990s, research into this important topic has declined. In the meantime, new tools and techniques for the characterization and functionalization of biological surfaces have been developed. This review summarizes the available literature regarding the physicochemical attributes of the ocular surface, analyzes the role of interfacial phenomena in the pathobiology of ocular surface disease, identifies critical knowledge gaps concerning interfacial phenomena of the ocular surface, and discusses the opportunities for the exploitation of these phenomena to develop improved therapeutics for the treatment of ocular surface disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Oculoplastic aspects of ocular oncology.

    Science.gov (United States)

    Rene, C

    2013-02-01

    It is estimated that 5-10% of all cutaneous malignancies involve the periocular region and management of periocular skin cancers account for a significant proportion of the oculoplastic surgeon's workload. Epithelial tumours are most frequently encountered, including basal cell carcinoma, squamous cell carcinoma, and sebaceous gland carcinoma, in decreasing order of frequency. Non-epithelial tumours, such as cutaneous melanoma and Merkel cell carcinoma, rarely involve the ocular adnexae. Although non-surgical treatments for periocular malignancies are gaining in popularity, surgery remains the main treatment modality and has as its main aims tumour clearance, restoration of the eyelid function, protection of the ocular surface, and achieving a good cosmetic outcome. The purpose of this article is to review the management of malignant periocular tumours, with particular emphasis on surgical management.

  5. Clinical manifestations of ocular toxoplasmosis.

    Science.gov (United States)

    Delair, Emmanuelle; Latkany, Paul; Noble, A Gwendolyn; Rabiah, Peter; McLeod, Rima; Brézin, Antoine

    2011-04-01

    Clinical manifestations of ocular toxoplasmosis are reviewed. Findings of congenital and acute acquired ocular toxoplasmosis include retinal scars, white-appearing lesions in the active phase often associated with vitritis. Complications can include fibrous bands, secondary serous or rhegmatogenous retinal detachments, optic neuritis and neuropathy, cataracts, increased intraocular pressure during active infection, and choroidal neovascular membranes. Recurrences in untreated congenital toxoplasmosis occur in teenage years. Manifestations at birth are less severe, and recurrences are fewer in those who were treated promptly early in the course of their disease in utero and in the first year of life. Severe retinal involvement is common at diagnosis of symptomatic congenital toxoplasmosis in the United States and Brazil. Acute acquired infections also may be complicated by toxoplasmic retinochoroiditis, with recurrences most common close to the time of acquisition. Suppressive treatment can reduce recurrent disease.

  6. Perforating ocular injury by Taser.

    Science.gov (United States)

    Chen, Sandy L; Richard, Christen K; Murthy, Raghu C; Lauer, Andreas K

    2006-01-01

    This report describes the features, treatment and outcome of globe perforation by a Taser dart electrode in a 21-year-old man. The Taser electrode caused mechanical iris, lens and retinal injury and consequent retinal detachment as result of proliferative vitreoretinopathy. The effect of electrical stimulation on ocular tissues is unknown. After the scleral and corneal wounds, traumatic cataract and retinal tear were repaired, the patient regained a visual acuity of 6/18. Nine months later a retinal detachment with proliferative vitreoretinopathy was discovered. The Taser may cause globe perforation and posterior segment injury. Understanding the barbed configuration of the dart electrode is important when extricating this device. Visual recovery is possible despite electric discharge of the Taser and suggests that the mechanism of ocular injury is largely mechanical.

  7. Oculoplastic aspects of ocular oncology

    OpenAIRE

    Rene, C

    2012-01-01

    It is estimated that 5–10% of all cutaneous malignancies involve the periocular region and management of periocular skin cancers account for a significant proportion of the oculoplastic surgeon's workload. Epithelial tumours are most frequently encountered, including basal cell carcinoma, squamous cell carcinoma, and sebaceous gland carcinoma, in decreasing order of frequency. Non-epithelial tumours, such as cutaneous melanoma and Merkel cell carcinoma, rarely involve the ocular adnexae. Alth...

  8. How Auditory Information Influences Volitional Control in Binocular Rivalry: Modulation of a Top-Down Attentional Effect

    Directory of Open Access Journals (Sweden)

    Manuel Vidal

    2011-10-01

    Full Text Available Although multistable perception has long been studied, in recent years, paradigms involving ambiguous visual stimuli have been used to assess phenomenal awareness. Indeed, for such stimuli, although the sensory input is invariant, a perceptual decision occurs bringing to awareness only one of the possible interpretations. Moreover, the observer experiences inevitable oscillations between these percepts. Only few studies have tackled bistability for multimodal percepts. Conrad et al. [1] presented dot fields going in opposite direction to each eye, they found that lateral sound motion prolongs the dominance duration of the coherent visual motion percept and not the other. In this study, the volitional control—the capacity to promote a given percept—was not assessed. Van Ee et al. [2] tested how sensory congruency influences volitional control using looming motion stimuli that could be seen, heard or sensed on the hand. They found that attention to the additional modality (sound or touch has to be engaged to promote visual dominance and that only temporal congruency is required in the end. In both studies such low-level stimuli could have reduced the possibility of finding passive interactions and limited the congruency to temporal features, which motivated the use of higher-level audio-visual speech processing in our experiments. Accordingly, we used the McGurk effect [4] involving robust audio-visual integration to investigate multimodal rivalry. After measuring the perceptual oscillation dynamics of rivaling videos (lips pronouncing /aba/ vs. /aga/, we added the sound /aba/ in order to assess the influence of audio-visual integration on the perceptual dynamics. Adding the sound /aba/ increased the dominance durations of both percepts when viewed passively. For McGurk sensitive participants, it also increased the capacity to promote lips uttering /aba/ percept as compared to the same situation without sound; but not for lips uttering /aga

  9. Neurophysiology and Neuroanatomy of Reflexive and Volitional Saccades as Revealed by Lesion Studies with Neurological Patients and Transcranial Magnetic Stimulation (TMS)

    Science.gov (United States)

    Muri, Rene M.; Nyffeler, Thomas

    2008-01-01

    This review discusses the neurophysiology and neuroanatomy of the cortical control of reflexive and volitional saccades in humans. The main focus is on classical lesion studies and studies using the interference method of transcranial magnetic stimulation (TMS). To understand the behavioural function of a region, it is essential to assess…

  10. Follicular lymphoma of the ocular adnexal region

    DEFF Research Database (Denmark)

    Rasmussen, Peter Kristian; Ralfkiaer, E.; Prause, J.U.

    2015-01-01

    Purpose To characterize the clinicopathological features of follicular lymphoma of the ocular adnexal region. Methods Retrospective nation-based study of Danish patients with ocular adnexal follicular lymphoma from January 1st 1980 through December 31st 2009. Results Twenty-four patients...... with ocular adnexal follicular lymphoma were identified. Fourteen (58%) of the patients were females. The median age was 63 years (range: 42–96 years). Eleven (46%) of the patients had primary ocular adnexal lymphoma, seven (29%) had an ocular adnexal lesion in conjunction with a concurrent systemic lymphoma...... and six patients (25%) presented with an ocular adnexal relapse. The most frequently affected sites were the lacrimal gland (38%) and the orbit (33%). Thirteen patients (54%) presented with Ann Arbor stage IE lymphoma, four (17%) had stage IIE, two patients (8%) stage IIIE, and five patients (21%) had...

  11. Ocular manifestations in children with cerebral palsy.

    Science.gov (United States)

    Sasmal, Nirmal Kumar; Maiti, Prasenjit; Mandal, Radhakrishna; Das, Debabrata; Sarkar, Subhra; Sarkar, Piyali; Biswas, Mukul Chandra; Dey, Asim Kumar; Chatterjee, Sanjay

    2011-05-01

    To evaluate the prevalence of ocular abnormalities among children with cerebral palsy, 140 patients with age between 6 months and 16 years were selected and the overall incidence of ocular abnormalities in this study was 42.1%. Two major ocular abnormalities identified in these cases were strabismus in 36.4%. Myopia was detected in 12.9% children while hypermetropia in 8.6% and astigmatism in 3.6% cases. Non-glaucomatous optic atrophy was present in 10.7% cases and nystagmus in 9.3% cases. Raised intra-ocular pressure was detected in 2.1% cases. Cortical visual impairment was seen in 20.7% children. Ocular abnormalities are frequent manifestations in cerebral palsy patients. Therefore, evaluation of all cerebral palsy cases emphasises the need for a full ophthalmological examination in order to detect ocular problems and to institute necessary therapy of the abnormalities for better livelihood of these physically challenged patients.

  12. Ocular myasthenia gravis: Side effect of urografin

    Directory of Open Access Journals (Sweden)

    Nitin Modi

    2016-01-01

    Full Text Available Ocular myasthenia gravis is an autoimmune disorder of the neuromuscular junction. Diplopia and ptosis are common symptoms at the onset of ocular myasthenia gravis. It may occur due to the antibodies developed against various drugs. We are reporting a case of ocular myasthenia gravis which was developed in a patient post angiography which may be due to antibody developed against the dye used in angiography.

  13. Volitional Mechanisms Mediate the Cuing Effect of Pitch on Attention Orienting: The Influences of Perceptual Difficulty and Response Pressure.

    Science.gov (United States)

    Chiou, Rocco; Rich, Anina N

    2015-02-01

    Our cognitive system tends to link auditory pitch with spatial location in a specific manner (ie high-pitched sounds are usually associated with an upper location, and low sounds are associated with a lower location). Recent studies have demonstrated that this cross-modality association biases the allocation of visual attention and affects performance despite the auditory stimuli being irrelevant to the behavioural task. There is, however, a discrepancy between studies in their interpretation of the underlying mechanisms. Whereas we have previously claimed that the pitch-location mapping is mediated by volitional shifts of attention (Chiou & Rich, 2012, Perception, 41: , 339-353), other researchers suggest that this cross-modal effect reflects automatic shifts of attention (Mossbridge, Grabowecky, & Suzuki, 2011, Cognition, 121: , 133-139). Here we report a series of three experiments examining the effects of perceptual and response-related pressure on the ability of nonpredictive pitch to bias visual attention. We compare it with two control cues: a predictive pitch that triggers voluntary attention shifts and a salient peripheral flash that evokes involuntary shifts. The results show that the effect of nonpredictive pitch is abolished by pressure at either perceptual or response levels. By contrast, the effects of the two control cues remain significant, demonstrating the robustness of informative and perceptually salient stimuli in directing attention. This distinction suggests that, in contexts of high perceptual demand and response pressure, cognitive resources are primarily engaged by the task-relevant stimuli, which effectively prevents uninformative pitch from orienting attention to its cross-modally associated location. These findings are consistent with the hypothesis that the link between pitch and location affects attentional deployment via volitional rather than automatic mechanisms. © 2015 SAGE Publications.

  14. Frontal alpha-delta EEG does not preclude volitional response during anaesthesia: prospective cohort study of the isolated forearm technique.

    Science.gov (United States)

    Gaskell, A L; Hight, D F; Winders, J; Tran, G; Defresne, A; Bonhomme, V; Raz, A; Sleigh, J W; Sanders, R D

    2017-10-01

    The isolated forearm test (IFT) is the gold standard test of connected consciousness (awareness of the environment) during anaesthesia. The frontal alpha-delta EEG pattern (seen in slow wave sleep) is widely held to indicate anaesthetic-induced unconsciousness. A priori we proposed that one responder with the frontal alpha-delta EEG pattern would falsify this concept. Frontal EEG was recorded in a subset of patients from three centres participating in an international multicentre study of IFT responsiveness following tracheal intubation. Raw EEG waveforms were analysed for power-frequency spectra, depth-of-anaesthesia indices, permutation entropy, slow wave activity saturation and alpha-delta amplitude-phase coupling. Volitional responses to verbal command occurred in six out of 90 patients. Three responses occurred immediately following intubation in patients (from Sites 1 and 2) exhibiting an alpha-delta dominant (delta power >20 dB, alpha power >10 dB) EEG pattern. The power-frequency spectra obtained during these responses were similar to those of non-responders (P>0.05) at those sites. A further three responses occurred in (Site 3) patients not exhibiting the classic alpha-delta EEG pattern; these responses occurred later relative to intubation, and in patients had been co-administered ketamine and less volatile anaesthetic compared with Site 1 and 2 patients. None of the derived depth-of-anaesthesia indices could robustly discrimate IFT responders and non-responders. Connected consciousness can occur in the presence of the frontal alpha-delta EEG pattern during anaesthesia. Frontal EEG parameters do not readily discriminate volitional responsiveness (a marker of connected consciousness) and unresponsiveness during anaesthesia. NCT02248623.

  15. Combining motivational and volitional approaches to reducing excessive alcohol consumption in pre-drinkers: a theory-based intervention protocol.

    Science.gov (United States)

    Caudwell, Kim M; Mullan, Barbara A; Hagger, Martin S

    2016-01-16

    Pre-drinking refers to the consumption of alcohol at home or a private residence prior to attending a subsequent social event. We present the study protocol of an online theory-based intervention to reduce pre-drinking and related harm in pre-drinking undergraduates, using behavior change techniques targeting the motivational and volitional phases of behaviour. A fully randomized 2 (autonomy support: present vs. absent) x 2 (implementation intention: present vs. absent) between-participants design will be used to ascertain the effectiveness of the intervention in reducing pre-drinking alcohol consumption and alcohol-related harm. Participants will complete a range of theory-based measures prior to being allocated to one of the four experimental conditions. Four weeks later, participants will complete a follow-up questionnaire comprised of theoretical and behavioral measures. The main and interactive effects of the intervention components in reducing our primary dependent variables, namely, pre-drinking alcohol consumption and alcohol-related harm at four-week follow-up will be tested. Baseline alcohol consumption and demographic information will be included in the analysis as covariates. This online intervention is the first to be developed to reduce pre-drinking alcohol consumption, a behaviour linked to increased risk of alcohol-related harm. The intervention targets motivational and volitional components of the behaviour change process and is therefore likely to lead to greater reductions in pre-drinking alcohol consumption and experience of alcohol-related harm compared to either approach in isolation. If successful, the intervention can be implemented across various contexts and in populations where pre-drinking is prevalent. ACTRN12614001102662 . Registered 16 October 2014.

  16. Cue-Reactive Rationality, Visual Imagery and Volitional Control Predict Cue-Reactive Urge to Gamble in Poker-Machine Gamblers.

    Science.gov (United States)

    Clark, Gavin I; Rock, Adam J; McKeith, Charles F A; Coventry, William L

    2016-11-01

    Poker-machine gamblers have been demonstrated to report increases in the urge to gamble following exposure to salient gambling cues. However, the processes which contribute to this urge to gamble remain to be understood. The present study aimed to investigate whether changes in the conscious experience of visual imagery, rationality and volitional control (over one's thoughts, images and attention) predicted changes in the urge to gamble following exposure to a gambling cue. Thirty-one regular poker-machine gamblers who reported at least low levels of problem gambling on the Problem Gambling Severity Index (PGSI), were recruited to complete an online cue-reactivity experiment. Participants completed the PGSI, the visual imagery, rationality and volitional control subscales of the Phenomenology of Consciousness Inventory (PCI), and a visual analogue scale (VAS) assessing urge to gamble. Participants completed the PCI subscales and VAS at baseline, following a neutral video cue and following a gambling video cue. Urge to gamble was found to significantly increase from neutral cue to gambling cue (while controlling for baseline urge) and this increase was predicted by PGSI score. After accounting for the effects of problem-gambling severity, cue-reactive visual imagery, rationality and volitional control significantly improved the prediction of cue-reactive urge to gamble. The small sample size and limited participant characteristic data restricts the generalizability of the findings. Nevertheless, this is the first study to demonstrate that changes in the subjective experience of visual imagery, volitional control and rationality predict changes in the urge to gamble from neutral to gambling cue. The results suggest that visual imagery, rationality and volitional control may play an important role in the experience of the urge to gamble in poker-machine gamblers.

  17. Myopic anisometropia: ocular characteristics and aetiological considerations

    National Research Council Canada - National Science Library

    Vincent, Stephen J; Collins, Michael J; Read, Scott A; Carney, Leo G

    2014-01-01

    Anisometropia represents a unique example of ocular development, where the two eyes of an individual, with an identical genetic background and seemingly subject to identical environmental influences...

  18. Medicina regenerativa y superficie ocular Regenerative medicine and ocular surface

    Directory of Open Access Journals (Sweden)

    Taimi Cárdenas Díaz

    2012-06-01

    Full Text Available En los últimos años se ha producido un extraordinario avance en los conocimientos relacionados con diferentes ramas biomédicas, entre ellas, la biología celular. Esto ha dado un notable impulso a una nueva rama de la medicina denominada medicina regenerativa. Esta nueva disciplina médica se basa fundamentalmente en los nuevos conocimientos sobre las células madre y en su capacidad de convertirse en células de diferentes tejidos. Una de las estructuras que tiene más interés, desde el punto de vista de la medicina regenerativa, es la superficie ocular. Por esto, se ha logrado notables progresos en la reconstrucción de la superficie ocular mediante la aplicación de procederes regenerativos. Los cultivos de células del epitelio corneal humano están siendo utilizados en el tratamiento de la insuficiencia limbar. Esto permite disminuir la incidencia de opacidades tipo Haze tras queratectomía fotorrefractiva, acelerar la curación y evitar la aparición de leucomas en pacientes con defectos epiteliares persistentes e intentar disminuir la incidencia de opacidades corneales en pacientes sometidos a queratectomía fototerapéutica por diferentes distrofias corneales.In the last few years, an extraordinary advance has taken place in the knowledge about several biomedical branches as is the case of cellular biology, which has remarkably encouraged the development of a new medical branch called regenerative medicine. This medical discipline is fundamentally based on the new knowledge on the stem cells and their capacity to become cells for different tissues. One of the most interesting structures for the regenerative medicine is the ocular surface. In the last few years, significant advances have been achieved in the field of the ocular surface reconstruction with regenerative procedures. Some cell cultures of the human corneal epithelium are being used to treat limber insufficiency, to reduce the incidence of haze-type opacities after

  19. Prolonged multifocal electroretinographic implicit times in the ocular ischemic syndrome

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Munch, Inger Christine; Sander, Birgit

    2010-01-01

    Purpose. To examine retinal function in chronic ocular ischemia using multifocal electroretinography (mfERG). Methods. Thirteen patients with unilateral ocular ischemic syndrome (OIS) underwent assessment of ophthalmic systolic blood pressure by ocular pneumoplethysmography, carotid artery patenc...

  20. Motor Response Selection in Overt Sentence Production: A Functional MRI Study

    Science.gov (United States)

    Tremblay, Pascale; Small, Steven L.

    2011-01-01

    Many different cortical areas are thought to be involved in the process of selecting motor responses, from the inferior frontal gyrus, to the lateral and medial parts of the premotor cortex. The objective of the present study was to examine the neural underpinnings of motor response selection in a set of overt language production tasks. To this aim, we compared a sentence repetition task (externally constrained selection task) with a sentence generation task (volitional selection task) in a group of healthy adults. In general, the results clarify the contribution of the pre-SMA, cingulate areas, PMv, and pars triangularis to the process of selecting motor responses in the context of sentence production, and shed light on the manner in which this network is modulated by selection mode. Further, the present study suggests that response selection in sentence production engages neural resources similar to those engaged in the production of isolated words and oral motor gestures. PMID:21994500

  1. Ontogenetic Development of Vestibulo-Ocular Reflexes in Amphibians.

    Science.gov (United States)

    Branoner, Francisco; Chagnaud, Boris P; Straka, Hans

    2016-01-01

    Vestibulo-ocular reflexes (VOR) ensure gaze stability during locomotion and passively induced head/body movements. In precocial vertebrates such as amphibians, vestibular reflexes are required very early at the onset of locomotor activity. While the formation of inner ears and the assembly of sensory-motor pathways is largely completed soon after hatching, angular and translational/tilt VOR display differential functional onsets and mature with different time courses. Otolith-derived eye movements appear immediately after hatching, whereas the appearance and progressive amelioration of semicircular canal-evoked eye movements is delayed and dependent on the acquisition of sufficiently large semicircular canal diameters. Moreover, semicircular canal functionality is also required to tune the initially omnidirectional otolith-derived VOR. The tuning is due to a reinforcement of those vestibulo-ocular connections that are co-activated by semicircular canal and otolith inputs during natural head/body motion. This suggests that molecular mechanisms initially guide the basic ontogenetic wiring, whereas semicircular canal-dependent activity is required to establish the spatio-temporal specificity of the reflex. While a robust VOR is activated during passive head/body movements, locomotor efference copies provide the major source for compensatory eye movements during tail- and limb-based swimming of larval and adult frogs. The integration of active/passive motion-related signals for gaze stabilization occurs in central vestibular neurons that are arranged as segmentally iterated functional groups along rhombomere 1-8. However, at variance with the topographic maps of most other sensory systems, the sensory-motor transformation of motion-related signals occurs in segmentally specific neuronal groups defined by the extraocular motor output targets.

  2. Ocular perfusion pressure and ocular blood flow in glaucoma.

    Science.gov (United States)

    Cherecheanu, A Popa; Garhofer, G; Schmidl, D; Werkmeister, R; Schmetterer, L

    2013-02-01

    Glaucoma is a progressive optic neuropathy of unknown origin. It has been hypothesized that a vascular component is involved in glaucoma pathophysiology. This hypothesis has gained support from studies showing that reduced ocular perfusion pressure is a risk factor for the disease. The exact nature of the involvement is, however, still a matter of debate. Based on recent evidence we propose a model including primary and secondary insults in glaucoma. The primary insult appears to happen at the optic nerve head. Increased intraocular pressure and ischemia at the post-laminar optic nerve head affects retinal ganglion cell axons. Modulating factors are the biomechanical properties of the tissues and cerebrospinal fluid pressure. After this primary insult retinal ganglion cells function at a reduced energy level and are sensitive to secondary insults. These secondary insults may happen if ocular perfusion pressure falls below the lower limit of autoregulation or if neurovascular coupling fails. Evidence for both faulty autoregulation and reduced hyperemic response to neuronal stimulation has been provided in glaucoma patients. The mechanisms appear to involve vascular endothelial dysfunction and impaired astrocyte-vessel signaling. A more detailed understanding of these pathways is required to direct neuroprotective strategies via the neurovascular pathway. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Ocular associations of metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Rupali Chopra

    2012-01-01

    Full Text Available Metabolic syndrome is a cluster of diseases including central obesity, dyslipidemia, hyperglycemia, and high blood pressure. People with metabolic syndrome have been shown to be at an increased risk of developing cardiovascular disease, beyond the risk associated with individual components of the syndrome. The association of diabetes and hypertension with retinopathy, cataract, and raised intraocular pressure is well known. This review highlights the association of metabolic syndrome, including all its components, with various ocular conditions such as retinopathy, central retinal artery occlusion, cataracts, and raised intraocular pressure.

  4. Raman Spectroscopy of Ocular Tissue

    Science.gov (United States)

    Ermakov, Igor V.; Sharifzadeh, Mohsen; Gellermann, Warner

    The optically transparent nature of the human eye has motivated numerous Raman studies aimed at the non-invasive optical probing of ocular tissue components critical to healthy vision. Investigations include the qualitative and quantitative detection of tissue-specific molecular constituents, compositional changes occurring with development of ocular pathology, and the detection and tracking of ocular drugs and nutritional supplements. Motivated by a better understanding of the molecular mechanisms leading to cataract formation in the aging human lens, a great deal of work has centered on the Raman detection of proteins and water content in the lens. Several protein groups and the hydroxyl response are readily detectable. Changes of protein compositions can be studied in excised noncataractous tissue versus aged tissue preparations as well as in tissue samples with artificially induced cataracts. Most of these studies are carried out in vitro using suitable animal models and conventional Raman techniques. Tissue water content plays an important role in optimum light transmission of the outermost transparent ocular structure, the cornea. Using confocal Raman spectroscopy techniques, it has been possible to non-invasively measure the water to protein ratio as a measure of hydration status and to track drug-induced changes of the hydration levels in the rabbit cornea at various depths. The aqueous humor, normally supplying nutrients to cornea and lens, has an advantageous anterior location for Raman studies. Increasing efforts are pursued to non-invasively detect the presence of glucose and therapeutic concentrations of antibiotic drugs in this medium. In retinal tissue, Raman spectroscopy proves to be an important tool for research into the causes of macular degeneration, the leading cause of irreversible vision disorders and blindness in the elderly. It has been possible to detect the spectral features of advanced glycation and advanced lipooxydation end products in

  5. Miasis ocular por Oestrus ovis

    Directory of Open Access Journals (Sweden)

    María Beltrán F

    2006-01-01

    Full Text Available Se presentan tres casos de miasis ocular (dos adultos y un niñoprocedentes de zonas ganaderas de la provincia de Huaura,departamento de Lima,que acudieron al Hospital Regional de Huacho por presentar el ojo rojo,fotofobia, edema palpebral y sensación de cuerpo extraño;se extrajeron larvas adheridas al canto interno del ojo,las cuales se recibieron en el Instituto Nacional de Salud y fueron identificadas como Oestrus ovis .

  6. Randomized controlled comparative study on effect of training to improve lower limb motor paralysis in convalescent patients with post-stroke hemiplegia

    OpenAIRE

    Kawakami, Kenji; Miyasaka, Hiroyuki; Nonoyama, Sayaka; Hayashi, Kazuya; Tonogai, Yusuke; Tanino,Genichi; Wada, Yosuke; Narukawa, Akihisa; Okuyama, Yuko; Tomita, Yutaka; Sonoda, Shigeru

    2015-01-01

    [Purpose] The motor paralysis-improving effect on the hemiplegic lower limb was compared among mirror therapy, integrated volitional-control electrical stimulation, therapeutic electrical stimulation, repetitive facilitative exercises, and the standard training method in post-stroke hemiplegia patients. [Subjects and Methods] Eighty one stroke patients admitted to a convalescent rehabilitation ward were randomly allocated to the above 5 treatment groups. Each patient performed functional trai...

  7. Ischemic Conditioning Increases Strength and Volitional Activation of Paretic Muscle in Chronic Stroke: A Pilot Study.

    Science.gov (United States)

    Hyngstrom, Allison S; Murphy, Spencer A; Nguyen, Jennifer; Schmit, Brian D; Negro, Francesco; Gutterman, David D; Durand, Matthew J

    2018-02-08

    Ischemic conditioning (IC) on the arm or leg has emerged as an intervention to improve strength and performance in healthy populations, but the effects on neurologic populations are unknown. The purpose of this study was to quantify the effects of a single session of IC on knee extensor strength and muscle activation in chronic stroke survivors. Maximal knee extensor torque measurements and surface EMG were quantified in 10 chronic stroke survivors (>1 year post-stroke) with hemiparesis before and after a single session of IC or Sham on the paretic leg. IC consisted of five minutes of compression with a proximal thigh cuff (inflation pressure = 225 mmHg for IC or 25 mmHg for Sham) followed by five minutes of rest. This was repeated five times. Maximal knee extensor strength, EMG magnitude, and motor unit firing behavior were measured before and immediately after IC or Sham. IC increased paretic leg strength by 10.6{plus minus}8.5 Nm while no difference was observed in the Sham group (change in Sham = 1.3{plus minus}2.9 Nm; p = 0.001 IC vs. Sham). IC-induced increases in strength were accompanied by a 31{plus minus}15% increase in the magnitude of muscle EMG during maximal contractions and a 5% decrease in motor unit recruitment thresholds during sub-maximal contractions. Individuals who had the most asymmetry in strength between their paretic and non-paretic legs had the largest increases in strength (r 2 = 0.54). This study provides evidence that a single session of IC can increase strength through improved muscle activation in chronic stroke survivors.

  8. Ocular trauma | Mustak | South African Family Practice

    African Journals Online (AJOL)

    Ocular trauma is an important cause of unilateral blindness and visual impairment across the world. Most injuries are accidental, work-related injuries in developed countries, while assaults predominate as a cause in developing countries. Trauma may result in various forms of ocular injuries, ranging from minor insult to ...

  9. Ocular changes in pregnant Nigerian women

    African Journals Online (AJOL)

    2011-05-06

    May 6, 2011 ... Objective: Pregnancy results in a lot of hormonal changes in the body and the eyes are no exception. These ocular changes could be physiologic, pathologic or a modification of a pre-existing condition. The aim of this study was to determine physiologic ocular changes that are associated with pregnancy in ...

  10. Ocular manifestation of granulomatosis with polyangitis

    Directory of Open Access Journals (Sweden)

    Mary Grace

    2015-01-01

    Full Text Available Ocular manifestation of granulomatosis with polyangitis. Proptosis is the most common ocular manifestation of granulomatosis with polyangitis. It is due to inflammation of the extraocular muscles or vasculitis of the vas nervosum. It is a poor prognostic sign.

  11. Ocular abnormalities in Floating-Harbor syndrome.

    Science.gov (United States)

    Asseidat, Ibrahim; Kaufman, Lawrence M

    2009-04-01

    We present the first case report of a comprehensive eye examination in a patient with Floating-Harbor syndrome. Ocular findings were limited to partially accommodative, acquired esotropia, and unusual eyelashes. A variety of other ocular features have been previously reported in the nonophthalmic medical literature and are herein reviewed.

  12. OCULAR FINDINGS IN CHILDREN WITH CEREBRAL PALSY ...

    African Journals Online (AJOL)

    Cerebral palsy is commonly associated with ocular abnormalities which often impact on their development and education. There is paucity of studies on this in Nigeria. We decided to study/ determine the prevalence of ocular abnormalities among children with cerebral palsy that attended the neurology clinic of University of ...

  13. Ocular findings following trauma from paintball sports.

    Science.gov (United States)

    Taban, M; Taban, M; Sears, J E

    2008-07-01

    To raise awareness of potential significant ocular damage and visual loss secondary to paintballs in those not wearing ocular protection and to report high incidence of chorioretinitis sclopetaria from paintball contusion. We reviewed cases of eye injury presenting to a single institution from 2000 to 2005. Those cases in which the injury was attributed to paintballs were identified and evaluated to determine ocular findings and visual prognosis. Ocular paintball injuries occurred in eight male subjects and one female subject (nine eyes) with an average age of 16 years (range, 11-26). None had ocular protection at the time of ocular injury. On initial examination, vitreous haemorrhage was present in six eyes (67%), maculopathy, hyphema, cataract, and commotio retinae were each present in four eyes (44%). Two eyes suffered retinal detachment and one eye an optic nerve avulsion. Chorioretinitis sclopetaria occurred in four eyes (44%). The final visual acuity was > or =20/40 in three eyes, 20/50 to 20/150 in two eyes, and paintballs can result in severe ocular damage and visual loss. Increased awareness and need for proper ocular protection should be emphasized by ophthalmologists. Chorioretinitis sclopetaria occurs with a high frequency and its presence should be recognized, as its management is different from retinal tear or detachment.

  14. Ocular Surface Reconstruction: Recent Innovations

    Directory of Open Access Journals (Sweden)

    Madhavan HN

    2009-01-01

    Full Text Available The ocular surface is exceptionally rich in complexity and functionality. Severe ocular surface disorders/conditions, such as chemical or thermal injuries, Stevens-Johnson syndrome (SJS, ocular cicatricial pemphigoid, neurotrophic keratopathy, chronic limbitis, and severe microbial keratitis cause significant morbidities and even corneal blindness. Hypofunction may be caused by Aniridia, Neurotrophy, Endocrine, Pterygium and Chronic limbitis Approximately 6000 patients are seen in Ocular Surface Clinic every year; almost 80% have some form of dry eyes. About 125 new patients of Stevens Johnson Syndrome are seen in a year of which approximately 25% may benefit from Cultured Epithelial Transplant and 75 new patients of thermal/chemical injury in a year of which almost 80% will benefit from Stem Cell Transplantation. Of the 128 severe vernal keratoconjunctivitis which were seen in the ocular surface clinic, 10% require stem cell transplantation. Nearly 30 new cases of Ocular cicatrical pemphigoid every year are seen and they may need stem cell transplantation. In addition, several patients with persistent epithelial defects may benefit from limbal stem cell transplantation to alleviate, maintain conjunctivalization regression and corneal avascularity limbal deficiency, and restore vision. Even if granted that this statistics is for a single large ophthalmic hospital, for a large country as India with 1.1 billion populations, the number of patients requiring corneal stem cell transplantation is enormous. Stem cells in the palisades of Vogt participate in regeneration and preservation of corneal transparency and avascularity. The diminished regenerative capacity seen in LSCD is characterized by persistent epithelial defects, erosion and ulceration, conjunctivalization and neovascularization, and chronic inflammation. Standard corneal transplantation for restoration of corneal clarity and avascularity is a contraindication in the surgical management

  15. Influence of refractive correction on ocular dominance

    Science.gov (United States)

    Nakayama, Nanami; Kawamorita, Takushi; Uozato, Hiroshi

    2010-07-01

    We investigated the effects of refractive correction and refractive defocus on the assessment of sensory ocular dominance. In 25 healthy subjects (4 males and 21 females) aged between 20 and 31 years, a quantitative measurement of sensory ocular dominance was performed with refractive correction and the addition of a positive lens on the dominant eye. Sensory ocular dominance was measured with a chart using binocular rivalry targets. The reversal point changed after the addition of a +1.00 D lens on the dominant eye in all subjects. However, sighting ocular dominance and stereopsis did not change after the addition of a positive lens on the dominant eye ( P > 0:05, Wilcoxon test). These results suggest that refractive correction affects sensory ocular dominance, indicating the possible development of a new type of occlusion for amblyopia in the future.

  16. Anterior Segment Imaging in Combat Ocular Trauma

    Directory of Open Access Journals (Sweden)

    Denise S. Ryan

    2013-01-01

    Full Text Available Purpose. To evaluate the use of ocular imaging to enhance management and diagnosis of war-related anterior segment ocular injuries. Methods. This study was a prospective observational case series from an ongoing IRB-approved combat ocular trauma tracking study. Subjects with anterior segment ocular injury were imaged, when possible, using anterior segment optical coherence tomography (AS-OCT, confocal microscopy (CM, and slit lamp biomicroscopy. Results. Images captured from participants with combat ocular trauma on different systems provided comprehensive and alternate views of anterior segment injury to investigators. Conclusion. In combat-related trauma of the anterior segment, adjunct image acquisition enhances slit lamp examination and enables real time In vivo observation of the cornea facilitating injury characterization, progression, and management.

  17. Recent advances on ocular Demodex infestation.

    Science.gov (United States)

    Cheng, Anny M S; Sheha, Hosam; Tseng, Scheffer C G

    2015-07-01

    To summarize recent advances on ocular Demodex infestation. Demodex infestation is a potential cause of ocular surface inflammation. The pathogenesis of Demodex in eliciting ocular surface inflammation has been further clarified. Cliradex is currently the treatment of choice, it comprises the most active ingredient of tea tree oil, that is terpinen-4-ol, which helps eradicate Demodex mites and reduce ocular surface inflammation. Ocular demodicosis is a common but overlooked eye disease that manifests a number of morbidities. Demodex folliculorum causes chronic anterior blepharitis whereas Demodex brevis causes posterior blepharitis, meibomian gland dysfunction, recurrent chalazia, and refractory keratoconjunctivitis. The lash sampling and microscopic counting method and in-vivo confocal microscopy are key diagnostic methods. Cliradex shows promising potential to reduce Demodex counts with additional antibacterial, antifungal, and anti-inflammatory actions.

  18. Clinical and Immunological Responses in Ocular Demodecosis

    Science.gov (United States)

    Kim, Jae Hoon; Chun, Yeoun Sook

    2011-01-01

    The purpose of this study was to investigate clinical and immunological responses to Demodex on the ocular surface. Thirteen eyes in 10 patients with Demodex blepharitis and chronic ocular surface disorders were included in this study and treated by lid scrubbing with tea tree oil for the eradication of Demodex. We evaluated ocular surface manifestations and Demodex counts, and analyzed IL-1β, IL-5, IL-7, IL-12, IL-13, IL-17, granulocyte colony-stimulating factor, and macrophage inflammatory protein-1β in tear samples before and after the treatment. All patients exhibited ocular surface manifestations including corneal nodular opacity, peripheral corneal vascularization, refractory corneal erosion and infiltration, or chronic conjunctival inflammatory signs before treatment. After treatment, Demodex was nearly eradicated, tear concentrations of IL-1β and IL-17 were significantly reduced and substantial clinical improvement was observed in all patients. In conclusion, we believe that Demodex plays an aggravating role in inflammatory ocular surface disorders. PMID:21935281

  19. Adult Ocular Toxocariasis Mimicking Ciliary Body Malignancy

    Directory of Open Access Journals (Sweden)

    Ahmad M. Mansour

    2014-01-01

    Full Text Available Purpose. To discuss an unusual presentation of ocular toxocariasis. Methods. Case report. Results. A 40-year-old woman presented with decreased vision in the left eye with a long history of recurrent red eye from uveitis. Eosinophilia and positive ELISA titers for Toxocara canis favored the diagnosis of ocular toxocariasis. Over 3 months, an anterior scleral mass had a rapid growth raising the possibility of medulloepithelioma, which rarely can mimic uveitic syndromes. Surgical plan changed from local excision to enucleation. Histopathology demonstrated a large homogeneous mass of chronic inflammatory cells with inflammation of the overlying thinned out sclera, medial rectus insertion, and limbal cornea. The triad of peripheral granuloma, eosinophilia, and positive blood serology established the diagnosis of ocular toxocariasis. Conclusions. Ocular toxocariasis can mimic ocular malignancy such as medulloepithelioma in adults and rarely presents as an anterior scleral mass.

  20. Pediatric ocular nanomedicines: Challenges and opportunities.

    Science.gov (United States)

    Sheybani, Natasha D; Yang, Hu

    2017-09-01

    The eye is a highly complex, yet readily accessible organ within the human body. As such, the eye is an appealing candidate target for a vast array of drug therapies. Despite advances in ocular drug therapy research, the focus on pediatric ocular drug delivery continues to be highly underrepresented due to the limited number of degenerative ocular diseases with childhood onset. In this review, we explore more deeply the reasons underlying the disparity between ocular therapies available for children and for adults by highlighting diseases that most commonly afflict children (with focus on the anterior eye) and existing prognoses, recent developments in ocular drug delivery systems and nanomedicines for children, and barriers to use for pediatric patients.

  1. The electric motor handbook

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, R.W.; Feltham, P. (eds.)

    2004-05-01

    This handbook outlines the important role that electric motors play in modern society. It covers the field of motor applications from various motor types to their use and repair. It also presents practical applications of electric motors and methods on motor efficiency. More than half of all electricity generated, and 75 per cent of all industrial electricity consumption is consumed by electric motors. Electrical personnel must be aware of all factors involved in electric motors in order to choose and apply the appropriate size of electric motor. These factors include efficiency, sizing and proper application. The efficient use and maximum life expectancy of electric motors depends on proper motor protection, control and maintenance. This handbook includes articles from leading experts on electric motors in modern electrical systems. The content includes: design considerations; proper electric motor sizing techniques; optimal electric motor application; electric motor protection technology; electric motor control principles; electric motor maintenance and troubleshooting; induction electric motors; electric motor bearing currents; electric motor bearing lubrication; electromagnetism; electric motor enclosures; electric motor testing; electric motor repair; DC electric motor; electric motor starters; electric motor brushes; industrial electric motors; electric motor diagrams; AC electric motors; electric motor wiring; electric motor service; electric motor rewinding; electric motor winding; diagram of electric motor wiring; electric motor kit; and, troubleshooting electric motors. A directory of motor manufacturers and suppliers was also included. refs., tabs., figs.

  2. Motor teams :

    Indian Academy of Sciences (India)

    . Switch. Welte et al, 1998, Gross et al, 2002. Motion of Lipid droplets in Drosophila embryos. Page 7. • Stochastic transitions between two species of motor yields Bidirectional motion. • Tuning of single-motor parameters. • No need to invoke a ...

  3. Componentes oculares em anisometropia The ocular components in anisometropia

    Directory of Open Access Journals (Sweden)

    David Tayah

    2007-06-01

    Full Text Available OBJETIVO: Comparar as correlações dos componentes oculares (comprimento axial, comprimento do segmento anterior, poder médio da córnea, profundidade da câmara vítrea e poder refrativo equivalente com o erro refrativo total do olho portador da menor e da maior ametropia em anisométropes. MÉTODOS: Foi realizado um "survey" analítico conduzido em população de 68 anisométropes de duas ou mais dioptrias atendida no Ambulatório da Clinica Oftalmológica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo Os anisométropes foram submetidos à refração estática objetiva e subjetiva, ceratometria e biometria ultra-sônica. RESULTADOS: Não houve diferença significativa entre os valores dos componentes oculares medidos dos olhos portadores da menor e da maior ametropia. Os olhos portadores da menor ametropia apresentaram as mesmas correlações significantes observadas em olhos emétropes, ou seja, correlação da refração com comprimento do segmento anterior e comprimento axial, e correlação do comprimento axial com poder corneano e profundidade da câmara vítrea. Os olhos portadores da maior ametropia apresentaram correlação significante da refração com o comprimento axial e do comprimento axial com a profundidade da câmara vítrea. Ainda em ambos os olhos observou-se correlação significante do poder do cristalino com a profundidade da câmara anterior. CONCLUSÃO: Os olhos portadores da menor ametropia desenvolveram as correlações mais freqüentemente observadas nos olhos emétropes. Os olhos portadores da maior ametropia não desenvolveram as mesmas correlações dos emétropes.PURPOSE: To asses the correlation between ocular components (axial length, anterior segment length, corneal power, vitreous length and equivalent power of the eye and refractive error in eyes with higher and lower ametropia of subjects with anisometropia. METHODS: An analytical survey was carried out in 68 patients

  4. Molecular motors

    Science.gov (United States)

    Allemand, Jean François Desbiolles, Pierre

    2015-10-01

    How do we move? More precisely, what are the molecular mechanisms that can explain that our muscles, made of very small components can move at a osopic scale? To answer these questions we must introduce molecular motors. Those motors are proteins, or small protein assemblies that, in our cells, transform chemical energy into mechanical work. Then, like we could do for a oscopic motor, used in a car or in a fan, we are going to study the basic behavior of these molecular machines, present what are their energy sources, calculate their power, their yield. If molecular motors are crucial for our oscopic movements, we are going to see that they are also essential to cellular transport and that considering the activity of some enzymes as molecular motors bring some interesting new insights on their activity.

  5. Combining motivational and volitional strategies to promote unsupervised walking in patients with fibromyalgia: study protocol for a randomized controlled trial.

    Science.gov (United States)

    Pastor, María-Ángeles; López-Roig, Sofía; Lledó, Ana; Peñacoba, Cecilia; Velasco, Lilian; Schweiger-Gallo, Inge; Cigarán, Margarita; Ecija, Carmen; Limón, Ramón; Sanz, Yolanda

    2014-04-11

    Fibromyalgia patients are often advised to engage in regular low- to moderate-intensity physical exercise. The need of fibromyalgia patients to walk has been stressed in previous research. Behavioral self-regulation theories suggest that a combination of motivational aspects (to develop or strengthen a behavioral intention: Theory of Planned Behavior) and volitional aspects (engagement of intention in behavior: implementation intentions) is more effective than a single intervention. In this paper, we describe a protocol for identifying the motivational processes (using the Theory of Planned Behavior) involved in the practice of walking (phase I) and for studying the efficacy of an intervention that combines motivational and volitional contents to enhance the acquisition and continuation of this exercise behavior (phase II). The paper also shows the characteristics of eligible individuals (women who do not walk) and ineligible populations (women who walk or do not walk because of comorbidity without medical recommendation to walk). Both groups consist of members of any of four patients' associations in Spain who are between 18 and 70 years of age and meet the London Fibromyalgia Epidemiology Study Screening Questionnaire criteria for fibromyalgia. Furthermore, using this study protocol, we will explore the characteristics of participants (eligible women who agreed to participate in the study) and nonparticipants (eligible women who refused to participate). Two studies will be conducted: Phase I will be a cross-sectional study, and phase II will be a triple-blind, randomized longitudinal study with two treatment groups and one active control group. The questionnaires were sent to a total of 2,227 members of four patients' associations in Spain. A total of 920 participants with fibromyalgia returned the questionnaires, and 582 were ultimately selected to participate. The first data gathered have allowed us to identify the characteristics of the study population and

  6. Acoustic myography: a noninvasive monitor of motor unit fatigue.

    Science.gov (United States)

    Barry, D T; Geiringer, S R; Ball, R D

    1985-01-01

    Acoustic myography is the recording of sounds produced by contracting muscle. These sounds become louder with increasing force of contraction. We have compared muscle sounds with surface EMG to monitor the dissociation of electrical from mechanical events (presumably, the loss of excitation-contraction coupling) which occur with motor unit fatigue. Acoustic signals were amplified using a standard phonocardiograph, recorded on FM magnetic tape, and digitally analyzed. Muscles were examined at rest, with intermittent contractions, and with sustained contractions. We found that with fatigue, the acoustic amplitude decayed, but the surface EMG amplitude did not. With decreased effort, however, the acoustic and the surface EMG amplitudes declined simultaneously. By simultaneously recording acoustic signals and needle EMG, individual motor units were resolved acoustically in two muscles with decreased numbers of motor units and increased motor unit size. Fasciculations also produced acoustic signals, although no acoustic signal has yet been found that correlates with fibrillations. Analysis of acoustic signals from muscle provides a noninvasive method for monitoring motor unit fatigue in vivo. It may also be useful in distinguishing muscle fatigue from decreased volition.

  7. Human ocular Thelaziasis in Karnataka

    Directory of Open Access Journals (Sweden)

    Prabhakar S Krishnachary

    2014-01-01

    Full Text Available Thelaziasis is an Arthropod-born disease of the eye and adnexa caused by Thelazia callipaeda, a nematode parasite transmitted by drosophilid flies to carnivores and humans. Because of its distribution mainly confined to South Asian countries and Russia, it is commonly known as Oriental Eye worm. It is often under-reported and not been given its due clinical importance. We report first case of human Thelaziasis from Hassan District, Karnataka. Five creamy-white, translucent worms were removed from the conjunctival sac of a 74-year-old male patient. Based on morphological characters, the worms were identified as nematodes belonging to the genus Thelazia and speciation was confirmed by CDC, Atlanta as callipaeda. Rarity of the disease and its ability to cause both extra and intraocular manifestations leading to ocular morbidity is the reason for presenting this case. From the available data, this is the first case report from Karnataka, India.

  8. [Ocular manifestations in xeroderma pigmentosum].

    Science.gov (United States)

    Süsskind, D; Berneburg, M; Rohrbach, J M

    2011-03-01

    The aim of this study was to evaluate ocular changes in patients with xeroderma pigmentosum (XP) and Cockayne syndrome (CS). Both diseases belong to the progeroid syndromes caused by single gene mutations with premature aging. Both syndromes are very rare autosomal recessive diseases caused by a gene defect leading to deficient DNA repair. 12 patients (4 female, 8 male) with XP between 3 and 67 years old and a 39-year-old female patient with CS were examined. The examination included visual acuity testing, slit lamp biomicroscopy, funduscopy and performance of a Schirmer test. Changes of the lids in the XP group included blepharitis in 7 patients, distichiasis in 2, and madarosis in 3 patients. 8 patients had multiple lentigines solares of the lids. One patient showed scars of the lower lids after excision of a squamous cell carcinoma and a basal cell carcinoma. Conjunctival lesions comprised a tumour of unknown origin of the conjunctiva in 1 patient, teleangiectasia of the conjunctiva in 5 patients, pterygia in 4, and pinguecula in 1 patient. Two patients had an intraepithelial melanosis of the conjunctiva, and one showed conjunctival nevi. Two patients had corneal scars and corneal vascularisation, another a significant conjunctivalisation of the cornea. A Schirmer test was feasible only in 3 patients. Tear production was markedly reduced in all these patients. Break-up time was shortened significantly in 6 patients examined. The patient with the CS showed atrophy of the pupillary rim and a subcapsular cataract. Funduscopically there were pigment epithelial changes. Patients with XP often exhibit ocular changes. Beside the light-dependent degenerative and inflammatory manifestations at the lids, the conjunctiva and the cornea patients with XP also develop malignancies early in life. The majority of patients suffer from dry eye symptoms. © Georg Thieme Verlag KG Stuttgart · New York.

  9. Ocular Dominance and Handedness in Golf Putting.

    Science.gov (United States)

    Dalton, Kristine; Guillon, Michel; Naroo, Shehzad A

    2015-10-01

    In golf, the impact of eye-hand dominance on putting performance has long been debated. Eye-hand dominance is thought to impact how golfers judge the alignment of the ball with the target and the club with the ball, as well as how golfers visualize the line of the putt when making decisions about the force needed to hit the ball. Previous studies have all measured ocular dominance in primary gaze only, despite golfers spending a significant amount of their time in a putting stance (bent at the hips, head tilted down). Thus, the purpose of this study was to assess ocular dominance in both primary gaze (aligning the ball with the target) and putting gaze (addressing the ball and aligning the club). This study investigated measuring pointing ocular dominance in both primary and putting gaze positions on 31 golfers (14 amateur, 7 club professionals, and 10 top professionals). All players were right-handed golfers, although one reported having no hand dominance and one reported being strongly left hand dominant. The results showed that (1) primary and putting gaze ocular dominances are not equal, nor are they predictive of each other; (2) the magnitude of putting ocular dominance is significantly less than the magnitude of primary gaze ocular dominance; (3) ocular dominance is not correlated with handedness in either primary or putting gaze; and (4) eye-hand dominance is not associated with increased putting skill, although ocular dominance may be associated with increased putting success. It is important that coaches assess golfers' ocular dominance in both primary and putting gaze positions to ensure they have the most accurate information upon which to base their vision strategy decisions.

  10. Ocular abnormalities in healthy Standardbred foals.

    Science.gov (United States)

    Barsotti, Giovanni; Sgorbini, Micaela; Marmorini, Paola; Corazza, Michele

    2013-07-01

    To determine the prevalence and describe ocular abnormalities in healthy Standardbred foals within 48 h of birth. One hundred and two neonatal foals. All foals had an unassisted delivery. On the basis of physical examination and the results of hematological and biochemical parameters, all foals were unaffected by systemic diseases. A complete ophthalmic examination was performed within 48 h of birth. Foals with ocular hemorrhages were re-examined weekly until the abnormalities were resolved. 65/102 (63.7%) foals did not show ocular abnormalities, while in 37/102 (36.3%) cases, ocular abnormalities were present. Retinal and subconjunctival hemorrhages were recorded in 19/102 (18.6%), and in 13/102 (12.7%), respectively. In 4/102 (3.9%) animals, an entropion of the lower eyelid was present. Only one foal (1%) showed a congenital nuclear unilateral cataract. No other ocular abnormalities were detected. However, all foals showed various degrees of remnants of hyaloid system. One week after the first ocular examination, retinal hemorrhages had resolved in 100% of the eyes, whereas subconjunctival hemorrhages had disappeared in all eyes by the second week following the first examination. The acquired ocular lesions observed with relatively high frequency in the examined healthy Standardbred foals were ocular hemorrhages, which always showed a good outcome. Although these abnormalities were present at birth, they were not considered strictly congenital but likely acquired during parturition. Instead, congenital ocular abnormalities were rarely diagnosed, and the entropion of the lower eyelid was the most common disease in the breed. © 2012 American College of Veterinary Ophthalmologists.

  11. Stepper motor

    Science.gov (United States)

    Dekramer, Cornelis

    1994-01-01

    The purpose of this document is to describe the more commonly used permanent magnet stepper motors for spaceflight. It will discuss the mechanical and electrical aspects of the devices, their torque behavior, those parameters which need to be controlled and measured, and test methods to be employed. It will also discuss torque margins, compare these to the existing margin requirements, and determine the applicability of these requirements. Finally it will attempt to generate a set of requirements which will be used in any stepper motor procurement and will fully characterize the stepper motor behavior in a consistent and repeatable fashion.

  12. Ocular chemical injuries and their management

    Directory of Open Access Journals (Sweden)

    Parul Singh

    2013-01-01

    Full Text Available Chemical burns represent potentially blinding ocular injuries and constitute a true ocular emergency requiring immediate assessment and initiation of treatment. The majority of victims are young and exposure occurs at home, work place and in association with criminal assaults. Alkali injuries occur more frequently than acid injuries. Chemical injuries of the eye produce extensive damage to the ocular surface epithelium, cornea, anterior segment and limbal stem cells resulting in permanent unilateral or bilateral visual impairment. Emergency management if appropriate may be single most important factor in determining visual outcome. This article reviews the emergency management and newer techniques to improve the prognosis of patients with chemical injuries.

  13. Rotura ocular posterior traumática

    Directory of Open Access Journals (Sweden)

    Laine García Ferrer

    Full Text Available El trauma ocular es una causa importante de morbilidad oftalmológica en el mundo con implicaciones socioeconómicas importantes para el paciente y sus familiares. Ocurre generalmente en adultos jóvenes, con una buena agudeza visual al inicio del evento traumático, la cual se verá comprometida según la severidad del trauma, las estructuras oculares que afecte y las complicaciones que puedan aparecer. Presentamos dos pacientes con rotura escleral posterior secundario a trauma ocular a globo abierto contuso. Se describe el manejo personalizado el seguimiento en cada caso y sus resultados visuales.

  14. Toxocariosis Ocular en Menores de Edad

    Directory of Open Access Journals (Sweden)

    Norma Ocampo

    2001-04-01

    Full Text Available La toxocariosis es una geohelmintiosis producida por la ingestión de
    huevos de Toxocara canis y T. catis, cuyos hospederos definitivos son el perro y el gato. En el humano las larvas producen el Síndrome de Migración Larvaria Visceral y Ocular; en este último produce una enfermedad grave que puede semejar un retinoblastoma (1,2. Los niños son más susceptibles a adquirir esta infección (3. Nuestro objetivo es determinar la frecuencia de toxocariosis ocular en menores de edad con sintomatología ocular.

  15. Repetitive peripheral magnetic neurostimulation of multifidus muscles combined with motor training influences spine motor control and chronic low back pain.

    Science.gov (United States)

    Massé-Alarie, Hugo; Beaulieu, Louis-David; Preuss, Richard; Schneider, Cyril

    2017-03-01

    The study tested whether combining repetitive peripheral magnetic stimulation (RPMS) and motor training of the superficial multifidus muscle (MF) better improved the corticomotor control of spine than training alone in chronic low back pain (CLBP). Twenty-one participants with CLBP were randomly allocated to [RPMS+training] and [Sham+training] groups for three sessions (S1-S3) over a week where MF was stimulated before training (volitional contraction). Training was also home-practiced twice a day. Changes were tested at S1 and S3 for anticipatory postural adjustments (APAs) of MF and semi-tendinosus (ST), MF EMG activation, cortical motor plasticity (transcranial magnetic stimulation) and pain/disability. The RPMS group showed immediate decrease of pain at S1, then improvement of MF activation, ST APA, M1 facilitation, and pain/disability at S3. Changes were larger when brain excitability was lower at baseline. Disability index remained improved one month later. Combining RPMS with training of MF in CLBP impacted motor planning, MF and lumbopelvic spine motor control and pain/disability one week after the onset of protocol. Brain plasticity might have favoured motor learning and improved daily lumbopelvic spine control without pain generation. Clinically, RPMS impacted the function by improving the gains beyond those reached by training alone in CLBP. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  16. Volitional and Real-Time Control Cursor Based on Eye Movement Decoding Using a Linear Decoding Model

    Directory of Open Access Journals (Sweden)

    Jinhua Zhang

    2016-01-01

    Full Text Available The aim of this study is to build a linear decoding model that reveals the relationship between the movement information and the EOG (electrooculogram data to online control a cursor continuously with blinks and eye pursuit movements. First of all, a blink detection method is proposed to reject a voluntary single eye blink or double-blink information from EOG. Then, a linear decoding model of time series is developed to predict the position of gaze, and the model parameters are calibrated by the RLS (Recursive Least Square algorithm; besides, the assessment of decoding accuracy is assessed through cross-validation procedure. Additionally, the subsection processing, increment control, and online calibration are presented to realize the online control. Finally, the technology is applied to the volitional and online control of a cursor to hit the multiple predefined targets. Experimental results show that the blink detection algorithm performs well with the voluntary blink detection rate over 95%. Through combining the merits of blinks and smooth pursuit movements, the movement information of eyes can be decoded in good conformity with the average Pearson correlation coefficient which is up to 0.9592, and all signal-to-noise ratios are greater than 0. The novel system allows people to successfully and economically control a cursor online with a hit rate of 98%.

  17. Rethinking volitional control over task choice in multitask environments: use of a stimulus set selection strategy in voluntary task switching.

    Science.gov (United States)

    Arrington, Catherine M; Weaver, Starla M

    2015-01-01

    Under conditions of volitional control in multitask environments, subjects may engage in a variety of strategies to guide task selection. The current research examines whether subjects may sometimes use a top-down control strategy of selecting a task-irrelevant stimulus dimension, such as location, to guide task selection. We term this approach a stimulus set selection strategy. Using a voluntary task switching procedure, subjects voluntarily switched between categorizing letter and number stimuli that appeared in two, four, or eight possible target locations. Effects of stimulus availability, manipulated by varying the stimulus onset asynchrony between the two target stimuli, and location repetition were analysed to assess the use of a stimulus set selection strategy. Considered across position condition, Experiment 1 showed effects of both stimulus availability and location repetition on task choice suggesting that only in the 2-position condition, where selection based on location always results in a target at the selected location, subjects may have been using a stimulus set selection strategy on some trials. Experiment 2 replicated and extended these findings in a visually more cluttered environment. These results indicate that, contrary to current models of task selection in voluntary task switching, the top-down control of task selection may occur in the absence of the formation of an intention to perform a particular task.

  18. Attitudes towards anorexia nervosa: volitional stigma differences in a sample of pre-clinical medicine and psychology students.

    Science.gov (United States)

    Bannatyne, Amy Jean; Stapleton, Peta Berenice

    2017-10-01

    Anorexia nervosa (AN) is a highly stigmatised condition, with treatment often involving multidisciplinary care. As such, understanding and comparing the attitudes of emerging mental health and medical professionals towards AN, within the content of sex-based differences, is pertinent to facilitate the development of targeted stigma interventions. Examine the volitional stigmatisation of AN in emerging medical and mental health professionals. Participants (N = 126) were medical (n = 41) and psychology students (n = 85) who completed a range of attitudinal outcome measures (e.g. Causal Attributions Scale, Eating Disorder Stigma Scale, Opinions Scale, Characteristics Scale and Affective Reaction Scale). Across both disciplines, men were found to exhibit significantly higher eating disorder (ED) stigma, considered AN to be a more trivial and weak illness, and attributed greater levels of blame and responsibility to AN sufferers. Men also had significantly lower biogenetic causal attributions. Compared with psychology students, medicine students exhibited slightly greater anticipation of negative reactions in response to AN, obtained higher selfish/vain scores and considered sociocultural factors to contribute "a lot" in the development and maintenance of AN. Overall, results indicate interventions aimed at improving ED mental health literacy are needed, specifically targeting males and potentially medical students.

  19. Tear Osmolarity and Ocular Surface Parameters as Diagnostic Markers of Ocular Graft-Versus-Host Disease.

    Science.gov (United States)

    Na, Kyung-Sun; Yoo, Young-Sik; Hwang, Kyu-Yeon; Mok, Jee-Won; Joo, Choun-Ki

    2015-07-01

    To evaluate the diagnostic value of tear osmolarity and several ocular surface parameters in screening for ocular surface alterations in ocular graft-vs-host disease (GVHD) patients. Case-control study. Sixty-three patients with ocular GVHD and 74 healthy participants were screened for ocular surface changes using the Ocular Surface Disease Index (OSDI), tear osmolarity, Schirmer test, tear break-up time (TBUT), and fluorescein corneal staining. The severity of ocular GVHD was diagnosed according to the National Institutes of Health (NIH) grading system. The diagnostic sensitivity and specificity and cutoff values were determined for each ocular parameter using a receiver operating characteristic (ROC) curve and area under the curve (AUC) analysis. Significance was defined at P tear osmolarity, corneal staining score, and OSDI score gradually increased as the severity of ocular GVHD increased, and Schirmer value gradually decreased as the GVHD grade increased in severity. The Schirmer test showed greatest diagnostic sensitivity and specificity for ocular GVHD (92.1% sensitivity, 85.7% specificity, cutoff = 9 mm), followed by the TBUT (87.3% sensitivity, 75.0% specificity, cutoff = 6 s), tear osmolarity (98.4% sensitivity, 60.7% specificity, cutoff = 311 mOsm/L), corneal staining score (66.7% sensitivity, 82.1% specificity, cutoff = 2), and OSDI score (77.8% sensitivity, 66.1% specificity, cutoff = 20.8). Multiple diagnostic modalities should be used to detect ocular surface changes in GVHD patients. The severity of ocular GVHD can be effectively monitored using tear osmolarity; however, additional studies are required. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Electroencephalographic identifiers of motor adaptation learning

    Science.gov (United States)

    Özdenizci, Ozan; Yalçın, Mustafa; Erdoğan, Ahmetcan; Patoğlu, Volkan; Grosse-Wentrup, Moritz; Çetin, Müjdat

    2017-08-01

    Objective. Recent brain-computer interface (BCI) assisted stroke rehabilitation protocols tend to focus on sensorimotor activity of the brain. Relying on evidence claiming that a variety of brain rhythms beyond sensorimotor areas are related to the extent of motor deficits, we propose to identify neural correlates of motor learning beyond sensorimotor areas spatially and spectrally for further use in novel BCI-assisted neurorehabilitation settings. Approach. Electroencephalographic (EEG) data were recorded from healthy subjects participating in a physical force-field adaptation task involving reaching movements through a robotic handle. EEG activity recorded during rest prior to the experiment and during pre-trial movement preparation was used as features to predict motor adaptation learning performance across subjects. Main results. Subjects learned to perform straight movements under the force-field at different adaptation rates. Both resting-state and pre-trial EEG features were predictive of individual adaptation rates with relevance of a broad network of beta activity. Beyond sensorimotor regions, a parieto-occipital cortical component observed across subjects was involved strongly in predictions and a fronto-parietal cortical component showed significant decrease in pre-trial beta-powers for users with higher adaptation rates and increase in pre-trial beta-powers for users with lower adaptation rates. Significance. Including sensorimotor areas, a large-scale network of beta activity is presented as predictive of motor learning. Strength of resting-state parieto-occipital beta activity or pre-trial fronto-parietal beta activity can be considered in BCI-assisted stroke rehabilitation protocols with neurofeedback training or volitional control of neural activity for brain-robot interfaces to induce plasticity.

  1. Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors.

    Science.gov (United States)

    DiGiovanna, Jack; Dominici, Nadia; Friedli, Lucia; Rigosa, Jacopo; Duis, Simone; Kreider, Julie; Beauparlant, Janine; van den Brand, Rubia; Schieppati, Marco; Micera, Silvestro; Courtine, Grégoire

    2016-10-05

    Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral context. To investigate this possibility, we recorded whole-body kinematics, muscle synergies, and hindlimb motor cortex modulation in freely moving rats performing a range of natural locomotor procedures. We found that the activation of hindlimb motor cortex preceded gait initiation. During overground locomotion, the motor cortex exhibited consistent neuronal population responses that were synchronized with the spatiotemporal activation of hindlimb motoneurons. Behaviors requiring enhanced muscle activity or skilled paw placement correlated with substantial adjustment in neuronal population responses. In contrast, all rats exhibited a reduction of cortical activity during more automated behavior, such as stepping on a treadmill. Despite the facultative role of the motor cortex in the production of locomotion in rats, these results show that the encoding of hindlimb features in motor cortex dynamics is comparable in rats and cats. However, the extent of motor cortex modulations appears linked to the degree of volitional engagement and complexity of the task, reemphasizing the importance of goal-directed behaviors for motor control studies, rehabilitation, and neuroprosthetics. We mapped the neuronal population responses in the hindlimb motor cortex to hindlimb kinematics and hindlimb muscle synergies across a spectrum of natural locomotion behaviors. Robust task-specific neuronal population responses revealed that the rat motor cortex displays similar modulation as other mammals during locomotion. However, the reduced motor cortex activity during more automated behaviors suggests a relationship between the degree of engagement and task complexity. This relationship

  2. Ocular Complications of Diabetes and Therapeutic Approaches

    Directory of Open Access Journals (Sweden)

    Victoria J. Vieira-Potter

    2016-01-01

    Full Text Available Diabetes mellitus (DM is a metabolic disease defined by elevated blood glucose (BG. DM is a global epidemic and the prevalence is anticipated to continue to increase. The ocular complications of DM negatively impact the quality of life and carry an extremely high economic burden. While systemic control of BG can slow the ocular complications they cannot stop them, especially if clinical symptoms are already present. With the advances in biodegradable polymers, implantable ocular devices can slowly release medication to stop, and in some cases reverse, diabetic complications in the eye. In this review we discuss the ocular complications associated with DM, the treatments available with a focus on localized treatments, and what promising treatments are on the horizon.

  3. The pathophysiology of ocular allergy: a review.

    Science.gov (United States)

    Chigbu, De Gaulle I

    2009-02-01

    Allergic eye disease is an abnormal immune hypersensitivity response to allergens. It is characterized by IgE-mediated and/or T-lymphocyte-mediated immune hypersensitivity reactions that lead to an immune response, resulting in the clinical manifestations of ocular allergy. This review will focus on immunopathophysiology of the different types of allergic eye disease commonly encountered in the primary care setting. The objective is to provide the clinician with a considerable understanding of the immunopathogenesis of allergic eye disease. The primary focus of this review will be on the antibody- and cell-mediated immune hypersensitivity reactions relevant to allergic eye disease, the different phases of ocular allergic immune response and the histopathological manifestations of these commonly encountered ocular allergies. The basic concepts of immunology with emphasis on adaptive immunity and lymphocyte activation, as well as the components of the immune system that are relevant to ocular allergy will also be reviewed.

  4. [Ocular toxoplasmosis and consecutive complicated cataract].

    Science.gov (United States)

    Corbu, Cătălina; Creţu, Carmen; Predoi, Daniela; Tatu, Mihaela

    2002-01-01

    The paper reports three clinical cases which have in common two elements: ocular toxoplasmosis and consecutive complicative cataract, the method of treatment, the evolution and the recovery visual acuity.

  5. Cisticercosis ocular Ocular cysticercosis: presentation of one case

    Directory of Open Access Journals (Sweden)

    David Botero

    1992-01-01

    Full Text Available

    Se presenta el caso de un paciente con un cisticerco retiniano, tratado sin éxito con praziquantel, quien a los cinco meses del tratamiento presentó fibrosis y desprendimiento de la retina. Se realizó intervención quirúrgica y se encontró el cisticerco vivo. Desde antes de la operación el paciente había perdido la visión por el ojo afectado. Se hace una revisión sobre oftalmocisticercosis y se recomienda tratamiento quirúrgico oportuno y no usar los antihelmínticos con efecto sobre los cisticercos, como son praziquantel y albendazol.

    One case of ocular cysticercosis with retinal involvement, in which praziquantel treatment was ineffective, is presented. Five months after the medical treatment the patient presented with retinal detachment and fibrosis, loss of vision through the affected eye and at that time the parasite was observed alive. Surgical intervention was performed and the recovered cysticercus showed viability. A review on ophtalmocysticercosis is presented and recommendations are made to treat these cases by early surgery without prior administration of anticysticercus drugs such as praziquantel or albendazole.

  6. Ocular features of multiple system atrophy.

    Science.gov (United States)

    Garcia, Maria D; Pulido, Jose S; Coon, Elizabeth A; Chen, John J

    2018-01-01

    The aim of this paper is to gain better understanding of the ocular manifestations of multiple system atrophy (MSA), a neurodegenerative disorder rarely studied in terms of its ophthalmologic features. We performed a retrospective case series (1/1/05-12/31/14) to search for patients seen at Mayo Clinic, Rochester, MN, who had mention of MSA in the medical record and an eye examination, which yielded 285 cases. Of the 285, we identified 39 cases of true MSA. Each of these 39 patients was further reviewed for ocular abnormalities potentially related to MSA. Ocular findings potentially attributable to MSA were found in 64% of patients. Most common were dry eye (N = 14), conjugate eye movement abnormalities (N = 13), and ocular misalignment (N = 7). One patient had dry eye and monocular diplopia from trichiasis due to cicatricial pemphigoid, one had bilateral optic atrophy, and one had Adie's tonic pupil. Conjugate eye movement abnormalities (33%) and ocular misalignment (18%) were more common in patients with MSA-C. Patients with ocular findings, excluding dry eye, had a significantly shorter lifespan from time of initial neurologic symptoms to death. Our study confirms conjugate eye movement abnormalities and misalignment are common ocular findings in patients with MSA. Bilateral optic atrophy and cicatricial pemphigoid are possibly attributable to the disease. Ocular manifestations in MSA predict a poor prognosis as these patients have a significantly shorter lifespan. Therefore, we recommend patients with MSA have a comprehensive neuro-ophthalmologic exam at time of diagnosis, and thereafter, to screen for eye findings that may indicate a shorter lifespan. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Prosthetic management of an ocular defect

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    Siddesh Kumar Chintal

    2010-01-01

    Full Text Available The disfigurement associated with the loss of an eye can cause significant physical and emotional problems. Various treatment modalities are available, one of which is implants. Although implant has a superior outcome, it may not be advisable in all patients due to economic factors. The present article describes the prosthetic management of an ocular defect with a custom-made ocular prosthesis.

  8. The role of complement in ocular pathology

    OpenAIRE

    Bora, Nalini S.; Jha, Purushottam; Bora, Puran S.

    2008-01-01

    Functionally active complement system and complement regulatory proteins are present in the normal human and rodent eye. Complement activation and its regulation by ocular complement regulatory proteins contribute to the pathology of various ocular diseases including keratitis, uveitis and age-related macular degeneration. Furthermore, a strong relationship between age-related macular degeneration and polymorphism in the genes of certain complement components/complement regulatory proteins is...

  9. Supplementary motor complex and disturbed motor control – a retrospective clinical and lesion analysis of patients after anterior cerebral artery stroke

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    Florian eBrugger

    2015-10-01

    Full Text Available Background: Both the supplementary motor complex (SMC, consisting of the supplementary motor area (SMA-proper, the pre-SMA and the supplementary eye field, and the rostral cingulate cortex (ACC are supplied by the anterior cerebral artery (ACA and are involved in higher motor control. The Bereitschaftspotential (BP originates from the SMC and reflects cognitive preparation processes before volitional movements. ACA strokes may lead to impaired motor control in the absence of limb weakness and evoke an alien-hand syndrome (AHS in its extreme form.Aim: To characterize the clinical spectrum of disturbed motor control after ACA strokes including signs attributable to AHS and to identify the underlying neuroanatomical correlates.Methods: A clinical assessment focusing on signs of disturbed motor control including intermanual conflict (i.e. bilateral hand movements directed at opposite purposes, lack of self-initiated movements, exaggerated grasping, motor perseverations, mirror movements and gait apraxia was performed. Symptoms were grouped into A AHS specific and B non-AHS specific signs of upper limbs and C gait apraxia. Lesion summation mapping was applied to the patients’ MRI or CT scans to reveal associated lesion patterns. The BP was recorded in two patients.Results: Ten patients with ACA strokes (9 unilateral, 1 bilateral; mean age: 74.2 years; median NIH-SS at admission: 13.0 were included in this case series. In the acute stage, all cases had marked difficulties to perform volitional hand movements, while movements in response to external stimuli were preserved. In the chronic stage (median follow-up: 83.5 days initiation of voluntary movements improved, although all patients showed persistent signs of disturbed motor control. Impaired motor control is predominantly associated with damaged voxels within the SMC and the anterior and medial cingulate cortex, while lesions within the pre-SMA are specifically related to AHS. No BP was detected

  10. Ocular toxoplasmosis: the influence of patient age

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    Gary N Holland

    2009-03-01

    Full Text Available The influence of patient age on various features of ocular toxoplasmosis has been a subject of study for many years. The age at which Toxoplasma gondii infection occurs in different populations is related to socioeconomic factors and studies suggest that ocular toxoplasmosis is a more severe disease at the extremes of age. The prevalence of ocular involvement is markedly different between individuals with congenital and those with post-natally acquired infections. Even among those with post-natally acquired infections, age influences the risk and timing of ocular involvement. The severity of toxoplasmic retinochoroiditis (in terms of lesion size, location and associated inflammation is also affected by patient age at the time of initial infection or recurrence. The risk of recurrent toxoplasmic retinochoroiditis is influenced by age at the time of initial infection and age at most recent episode of active disease. Understanding of relationships between ocular toxoplasmosis and patient age is incomplete; evidence has often been indirect and in some cases conflicting. The influence of patient age on ocular toxoplasmosis should be studied in a systematic manner to provide a better understanding of disease mechanisms and to provide clinical information that can used to establish better strategies for disease treatment and prevention.

  11. Ocular and periocular hemangiosarcoma in six horses.

    Science.gov (United States)

    Scherrer, Nicole M; Lassaline, Mary; Engiles, Julie

    2017-11-07

    To determine the characteristics of and prognosis for ocular and periocular hemangiosarcoma in horses. Six horses treated for ocular or periocular hemangiosarcoma. A retrospective review of medical records from 2007 to 2015 was performed to identify horses with a histologic diagnosis of ocular or periocular hemangiosarcoma. Signalment (age, sex, breed), duration of clinical signs, prior treatment, tumor size and location, medical and surgical treatment including postoperative chemotherapy, follow-up time, and outcome were obtained from medical records. Histopathology was reviewed by a board-certified pathologist. In six horses diagnosed with ocular or periocular hemangiosarcoma, no breed, age, or sex was overrepresented. Sites included the temporal limbus (3), third eyelid (2), and uvea (1). With the exception of one horse with uveal hemangiosarcoma, 5/6 horses had lightly pigmented periocular haircoat. Histologic features of ocular hemangiosarcoma in 6/6 cases included high cellularity, nuclear pleomorphism, and inflammation with a mitotic index ranging from 0 to 8 mitoses per 10 consecutive 400× fields. Five of six tumors displayed solar elastosis, indicating ultraviolet light-induced damage to sub-epithelial collagen. Treatment included surgical excision in all cases and was not associated with recurrence in 4/6. Three cases that received ancillary treatment with topical mitomycin C had no postoperative recurrence. Two cases with postexcisional recurrence had histologic evidence of incomplete excision. Complete surgical excision may be associated with resolution of periocular and ocular hemangiosarcoma in horses. Etiopathogenesis may include exposure to ultraviolet light. © 2017 American College of Veterinary Ophthalmologists.

  12. Ocular biometric changes after trabeculectomy

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    Azam Alvani

    2016-01-01

    Full Text Available This review article aimed to evaluate ocular biometric changes after trabeculectomy. The PubMed database was searched using the keywords “axial length” (AL, “anterior chamber depth” (ACD, “corneal astigmatism,” “corneal topography” and “trabeculectomy.” The extracted studies were categorized based on the evaluated parameters and the biometry method (contact and non-contact. Comparable studies with respect to their sample size were combined for statistical analysis. Twenty-five studies including 690 individuals which met the inclusion criteria were selected. After trabeculectomy, a significant and persistent AL reduction, with a range of 0.1-0.19 and 0.1-0.9 mm measured with contact and non-contact methods, respectively, was observed. With respect to topographic changes, 0.38-1.4 diopters (D with-the-rule (WTR astigmatism was induced postoperatively. All studies revealed ACD reduction immediately after surgery, which gradually deepened and approximated its preoperative levels on day 14. ACD reduction was not significant after that period in the majority of cases. In conclusion, changes in ACD is of small amount and of short period, thus it can be ignored; however, reported changes in AL and keratometry are of sufficient magnitude and can affect the refractive prediction of combined cataract surgery and trabeculectomy.

  13. Ocular microtremor laser speckle metrology

    Science.gov (United States)

    Al-Kalbani, M.; Mihaylova, E.; Collins, N.; Toal, V.; Coakley, D.; Boyle, G.

    2009-02-01

    Ocular Microtremor (OMT) is a continual, high frequency physiological tremor of the eye present in all subjects even when the eye is apparently at rest. OMT causes a peak to peak displacement of around 150nm-2500nm with a broadband frequency spectrum between 30Hz to 120Hz; with a peak at about 83Hz. OMT carries useful clinical information on depth of consciousness and on some neurological disorders. Nearly all quantitative clinical investigations have been based on OMT measurements using an eye contacting piezoelectric probe which has low clinical acceptability. Laser speckle metrology is a candidate for a high resolution, non-contacting, compact, portable OMT measurement technique. However, tear flow and biospeckle might be expected to interfere with the displacement information carried by the speckle. The paper investigates the properties of the scattered speckle of laser light (λ = 632.8nm) from the eye sclera to assess the feasibility of using speckle techniques to measure OMT such as the speckle correlation. The investigation is carried using a high speed CMOS video camera adequate to capture the high frequency of the tremor. The investigation is supported by studies using an eye movement simulator (a bovine sclera driven by piezoelectric bimorphs). The speckle contrast and the frame to frame spatiotemporal variations are analyzed to determine if the OMT characteristics are detectable within speckle changes induced by the biospeckle or other movements.

  14. Ocular features of CHARGE syndrome.

    Science.gov (United States)

    McMain, Karen; Blake, Kim; Smith, Isabel; Johnson, Judy; Wood, Ellen; Tremblay, Francois; Robitaille, Johane

    2008-10-01

    To detail the presence and severity of ocular and cranial nerve abnormalities found in individuals with CHARGE syndrome in a distinct geographic area. Nine individuals with CHARGE syndrome from Maritime Canada identified from a Canadian database were prospectively examined. Structural and sensorial defects associated with functional visual deficits were defined with ophthalmic and neurological evaluation. Consistent with current diagnostic criteria and the literature, colobomas were the major ophthalmic manifestation. These were typically bilateral chorioretinal colobomas involving the optic nerve. All subjects had bilateral severe sensorineural deafness (cranial nerve VIII), and 8 of 9 (89%) had facial nerve (cranial nerve VII) involvement (7 of 9 had unilateral involvement; 1 of 9 had bilateral involvement). Unique to this group of participants were the findings of anisometropia in 8 of the 9 (89%) patients, severe myopic astigmatism in 13 of the 18 eyes (72%), and limited elevation in adduction in 3 of 9 (33%) participants. Associated findings were strabismus, cataracts, microcornea, keratopathy, staphyloma, reduced stereopsis, superior visual field defects, and reduced visual acuity. The presence of coloboma plus another CHARGE feature warrants further investigation, including genetic screening for the CHD7 gene. Early recognition and management of sensory problems (visual, auditory, and vestibular) are crucial to ensure best psychomotor and cognitive development.

  15. Diagnostic tools in ocular allergy.

    Science.gov (United States)

    Leonardi, A; Doan, S; Fauquert, J L; Bozkurt, B; Allegri, P; Marmouz, F; Rondon, C; Jedrzejczak, M; Hellings, P; Delgado, L; Calder, V

    2017-10-01

    Ocular allergy (OA) includes a group of common and less frequent hypersensitivity disorders frequently misdiagnosed and not properly managed. The diagnosis of OA is usually based on clinical history and signs and symptoms, with the support of in vivo and in vitro tests when identification of the specific allergen is required. To date, no specific test is available for the diagnosis of the whole spectrum of the different forms of OA. The lack of recommendations on diagnosis of OA is considered a medical need not only for allergists but also for ophthalmologists. This position paper aims to provide a comprehensive overview of the currently available tools for diagnosing OA to promote a common nomenclature and procedures to be used by different specialists. Questionnaires, sign and symptom grading scales, tests, and potential biomarkers for OA are reviewed. We also identified several unmet needs in the diagnostic tools to generate interest, increase understanding, and inspire further investigations. Tools, recommendations, and algorithms for the diagnosis of OA are proposed for use by both allergists and ophthalmologists. Several unmet needs in the diagnostic tools should be further improved by specific clinical research in OA. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  16. An update on ocular allergy.

    Science.gov (United States)

    Shaker, Marcus; Salcone, Erin

    2016-10-01

    The update reviews prevalence, classification, cause, and treatment options for allergic eye disease. The incidence of allergic eye disease is underreported but may affect almost all patients with allergic rhinitis. Increased rates of oculonasal symptoms have been reported in the United States resulting in significant economic expenditures. The spectrum of allergic conjunctivitis and its differential considerations include seasonal and perennial conjunctivitis, vernal and atopic keratoconjunctivitis, and giant papillary conjunctivitis. Patients with allergic conjunctivitis have classic immunoglobulin E-mediated pathophysiology and treatments directed at allergen avoidance, traditional pharmacotherapy with oral antihistamines, topical dual-acting antihistamine/mast cell stabilizer agents, and treatment of tear film dysfunction are first-line management strategies. Immunotherapy is an effective treatment option and refractory cases may require ophthalmology comanagement for consideration of topical ester-based corticosteroid therapy and consideration of topical immunomodulators. Ocular allergy involving specific modifiable and treatable environmental sensitizations is common and often underrecognized. It can impair quality of life to varying degrees. Some cases are quite refractory to management and may require multidisciplinary coordination of care between allergy and ophthalmology specialists. Understanding classification, triggers, and treatment options is important in designing the most appropriate patient-tailored management plans.

  17. Zooming in on children's behavior during delay of gratification: Disentangling impulsigenic and volitional processes underlying self-regulation.

    Science.gov (United States)

    Neuenschwander, Regula; Blair, Clancy

    2017-02-01

    When delaying gratification, both motivational and regulatory processes are likely to be at play; however, the relative contributions of motivational and regulatory influences on delay behavior are unclear. By examining behavioral responses during a delay task, this study sought to examine the motivational (anticipatory behavior) and regulatory mechanisms (executive function and self-control strategies) underlying children's self-regulation. The participants, 65 5- to 9-year-old children (Mage=7.19years, SD=0.89), were video-recorded during a delay procedure and later coded for anticipatory behaviors (e.g., gazing intensely at the tablet) and self-control strategies. Children also completed two executive function (EF) tasks. We found that anticipatory behavior was curvilinearly related to delay time. Children showing either very low or very high levels of anticipatory behavior were not able to wait the entire time. Furthermore, our results indicated that anticipatory behavior interacted with EF to predict delay time. Specifically, anticipatory behavior was negatively related to delay time only if EF abilities were low. Finally, self-control strategies also interacted with EF to predict children's ability to delay. Spontaneous engagement in self-control strategies such as fidgeting and engagement in alternative activities were beneficial for children with low EF but were unrelated to delay time for children with high EF. Results indicate the value of examining motivational and regulatory influences on delay behavior. Lapses in self-regulation may be due to the combination of powerful impulsigenic (i.e., anticipatory behavior) and weak volitional processes (i.e., EF, self-control strategies). Copyright © 2016. Published by Elsevier Inc.

  18. Talented football players' development of achievement motives, volitional components, and self-referential cognitions: A longitudinal study.

    Science.gov (United States)

    Feichtinger, Philip; Höner, Oliver

    2015-01-01

    Adolescence is regarded as a key developmental phase in the course of talented football players' careers. The present study focuses on early adolescent players' development of achievement motives, volitional components, and self-referential cognitions. Based on the multidimensional and dynamic nature of talent, the development of multifaceted personality characteristics is an important issue in the context of sports talent research. According to previous findings in psychology, personality characteristics' development is defined by both stability and change, and the current study analyses four different types: differential stability (I), mean-level change (II), individual-level change (III), and structural stability (IV). The sample consists of 151 male players in the talent development programme of the German Football Association. Psychological diagnostics of the personality characteristics are implemented across longitudinal sections over a time period of three seasons, from the U12 to U14 age classes. The results reveal that the personality characteristics show (I) moderate test-retest correlations over one-year intervals (.43 ≤ rtt ≤ .62), and lower coefficients for a two-year period (.26 ≤ rtt ≤ .53). (II) Most of the personality characteristics' mean values differ significantly across the age classes with small effect sizes (.01 ≤ [Formula: see text] ≤ .03). (III) Only minor individual-level changes in the football players' development are found. (IV) The personality characteristics' associations within a two-factor structure do not stay invariant over time. From the results of the present study, conclusions are drawn regarding the talent identification and development process.

  19. Social-Ecological, Motivational and Volitional Factors for Initiating and Maintaining Physical Activity in the Context of HIV.

    Science.gov (United States)

    Ley, Clemens; Barrio, María Rato; Leach, Lloyd

    2015-01-01

    Sport and exercise can have several health benefits for people living with HIV. These benefits can be achieved through different types of physical activity, adapting to disease progression, motivation and social-ecological options. However, physical activity levels and adherence to exercise are generally low in people living with HIV. At the same time, high drop-out rates in intervention studies are prevalent; even though they often entail more favourable conditions than interventions in the natural settings. Thus, in the framework of an intervention study, the present study aims to explore social-ecological, motivational and volitional correlates of South African women living with HIV with regard to physical activity and participation in a sport and exercise health promotion programme. The qualitative data was produced in the framework of a non-randomised pre-post intervention study that evaluated structure, processes and outcomes of a 10-week sport and exercise programme. All 25 participants of the programme were included in this analysis, independent of compliance. Data was produced through questionnaires, participatory group discussions, body image pictures, research diaries and individual semi-structured interviews. All participants lived in a low socioeconomic, disadvantaged setting. Hence, the psychological correlates are contextualised and social-ecological influences on perception and behaviour are discussed. The results show the importance of considering social-cultural and environmental influences on individual motives, perceptions and expectancies, the fear of disclosure and stigmatisation, sport and exercise-specific group dynamics and self-supporting processes. Opportunities and strategies to augment physical activity and participation in sport and exercise programmes in the context of HIV are discussed.

  20. Estudio sobre traumatismos oculares Study on ocular traumas

    Directory of Open Access Journals (Sweden)

    Ileana Miguel Pérez

    2004-06-01

    Full Text Available Se realizó estudio retrospectivo longitudinal de pacientes con traumatismos oculares mecánicos hospitalizados en el Instituto Superior de Medicina Militar "Dr. Luis Díaz Soto", desde 1988 hasta el 2002, con una casuística de 508 ojos de 479 pacientes. El procesamiento estadístico fue realizado con el mismo programa automatizado con el que se conformó la base de datos (Acces y se utilizaron de acuerdo con las características de las variables ß analizadas métodos estadísticos paramétricos y no paramétricos con una confiabilidad de un 95 % (a =0,05. Se obtiene una relación de 4:1 de predominio del sexo masculino, con una edad promedio de 27,4 años con valor mínimo de 2 años y máximo de 78 años. Los mecanismos más frecuentes de producción del accidente resultaron ser: las armas de fuego (22,7 % y la acción de martillar (21,4 %, teniendo en cuenta que el 38,2 % de los pacientes fueron militares. Las lesiones asociadas a los traumatismos más frecuentes resultaron ser el hipema y el hemovítreo, y se demostró que a medida que eran mayores disminuía considerablemente la agudeza visual final. Los traumatismos cerrados (41,3 % fueron más frecuentes y tuvieron mejores resultados visuales finales (66,7 % con visión mayor de 0.1 que el resto de los grupos de traumatismos abiertos (herida simple, contusión-herida, herida con CEIO y contusión-herida con CEIO. Las contusiones-heridas con CEIO fueron provocados en su mayoría por las armas de fuego y tuvieron los peores resultados visuales (60,5 % con visión menor de 0.1. La afectación del segmento posterior resultó ser un elemento que influyó de forma importante en los resultados visuales. Las complicaciones más frecuentes para los traumatismos cerrados fueron la hipertensión secundaria la catarata y el desprendimiento de retina. Para las heridas simples la catarata y para el resto de los traumatismos el desprendimiento de retina y la ptisis bulbi. Aproximadamente el 15 % de

  1. Systematic analysis of ocular trauma by a new proposed ocular trauma classification.

    Science.gov (United States)

    Shukla, Bhartendu; Agrawal, Rupesh; Shukla, Dhananjay; Seen, Sophia

    2017-08-01

    The current classification of ocular trauma does not incorporate adnexal trauma, injuries that are attributable to a nonmechanical cause and destructive globe injuries. This study proposes a new classification system of ocular trauma which is broader-based to allow for the classification of a wider range of ocular injuries not covered by the current classification. A clinic-based cross-sectional study to validate the proposed classification. We analyzed 535 cases of ocular injury from January 1, 2012 to February 28, 2012 over a 4-year period in an eye hospital in central India using our proposed classification system and compared it with conventional classification. The new classification system allowed for classification of all 535 cases of ocular injury. The conventional classification was only able to classify 364 of the 535 trauma cases. Injuries involving the adnexa, nonmechanical injuries and destructive globe injuries could not be classified by the conventional classification, thus missing about 33% of cases. Our classification system shows an improvement over existing ocular trauma classification as it allows for the classification of all type of ocular injuries and will allow for better and specific prognostication. This system has the potential to aid communication between physicians and result in better patient care. It can also provide a more authentic, wide spectrum of ocular injuries in correlation with etiology. By including adnexal injuries and nonmechanical injuries, we have been able to classify all 535 cases of trauma. Otherwise, about 30% of cases would have been excluded from the study.

  2. Categorical evaluation of the ocular irritancy of cosmetic and consumer products by human ocular instillation procedures.

    Science.gov (United States)

    Gao, Yang; Kanengiser, Bruce E

    2004-01-01

    The assessment of ocular irritation potential is an important part of safety testing for cosmetic and consumer products. The purpose of this investigation was to examine ocular irritancy levels elicited in humans by various categories of a specific class of cosmetic and consumer products that have a potential to enter the eye inadvertently during use. Test materials assessed belonged to one of seven categories, which included liquid makeup, shampoo, baby wash, mascara, eye makeup remover, powder eye shadow, and facial cleanser. These test materials were evaluated by human ocular instillation, followed by examinations, for which subjective perceptions of irritation were recorded, and component areas of ocular tissues were individually examined for inflammation and for the area and density of fluorescein staining patterns at 30 seconds and at 5, 15, 60, and 120 minutes post-instillation. Subjective and objective ocular irritation scores of 410 eyes were analyzed by product classification. Average score levels were determined for subjective responses, inflammation, and fluorescein staining patterns. This investigation determined that irritation levels of the evaluated test materials varied markedly with respect to product category, type of ocular irritation, and ocular tissue, demonstrating that these factors are important considerations for the prediction of the ocular irritancy of a test material.

  3. Clinical analysis of firearm ocular injury

    Directory of Open Access Journals (Sweden)

    Ying ZHANG

    2011-10-01

    Full Text Available Objective To investigate and analyze the clinical characters and prognosis of firearm ocular injury.Methods The traumatic characters of military inpatients with firearm-produced ocular injury(hospitalized in 15 military general hospitals during 2001-2005 were retrospectively reviewed and statistically analyzed.Results Of 716 military inpatients with ocular injuries(772 eyes,42(5.9%,all were men,aged 23.2±5.4 years were produced by firearm [with 60 injured eyes(7.8%].Among the 42 inpatients,18 cases(42.9% were binocular injury,and in 13 cases(31.0% it was complicated with brain and/or limb injury.The causes of injury included explosion(78.3% and foreign bodies in ocular region(68.3%,among which 41.7% of them with intraocular foreign bodies,and 72.0% were copper in nature.Combined ocular injuries were usually seen,but no endophthalmitis was found.Intraocular surgery was necessary for 61.7% of injured eyes,and vitrectomy was performed for 33.3% of injured eyes.According to the data collected at discharge from the hospital,15.0% of injured eyes were enucleated or eviscerated,8.3% showed monocular low vision and 11.9% binocular low vision,and 33.3% of them were monocular blind and 2.4% binocular blind.There was significant correlation between the post-traumatic visual acuity and the final vision(r=0.457,and the vision was improved significantly by treatment(P < .01.Conclusions The degree of trauma of firearm-induced ocular injury was usually severe and complicated with poor visual prognosis.Therefore the emphasis should be put on improvement of emergency and clinical treatment for firearm ocular injury.

  4. Ocular Biometry in Angle Closure

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    Mohammad Reza Razeghinejad

    2013-01-01

    Full Text Available Purpose: To compare ocular biometric parameters in primary angle closure suspects (PACS, primary angle closure glaucoma (PACG and acute primary angle closure (APAC. Methods: This cross-sectional study was performed on 113 patients including 33 cases of PACS, 45 patients with PACG and 35 subjects with APAC. Central corneal thickness (CCT, axial length (AL, anterior chamber depth (ACD and lens thickness (LT were measured with an ultrasonic biometer. Lens-axial length factor (LAF, relative lens position, corrected ACD (CACD and corrected lens position were calculated. The parameters were measured bilaterally but only data from the right eyes were compared. In the APAC group, biometric parameters were also compared between affected and unaffected fellow eyes. Logistic regression analysis was performed to identify risk factors. Results: No statistically significant difference was observed in biometric parameters between PACS and PACG eyes, or between affected and fellow eyes in the APAC group (P>0.05 for all comparisons. However, eyes with APAC had thicker cornea (P=0.001, thicker lens (P<0.0001, shallower ACD (P=0.009, shallower CACD (P=0.003 and larger LAF (P<0.0001. Based on ROC curve analysis, lower ACD, and larger LT, LAF and CCT values were associated with APAC. In the APAC group, LAF (P<0.0001 and CCT (P=0.001 were significant risk factors. Conclusion: This study revealed no significant difference in biometric characteristics in eyes with PACS and PACG. However, larger LAF and CCT were predictive of APAC.

  5. Ocular changes in primary hypothyroidism

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    Pekel Hamiyet

    2009-12-01

    Full Text Available Abstract Background To determine the ocular changes related to hypothyrodism in newly diagnosed patients without orbitopathy. Findings Thirty-three patients diagnosed to have primary overt hypothyroidism were enrolled in the study. All subjects were assigned to underwent central corneal thickness (CCT, anterior chamber volume, depth and angle measurements with the Scheimpflug camera (Pentacam, Oculus and cup to disc ratio (C/D, mean retinal thickness and mean retinal nerve fiber layer (RNFL thickness measurements with optical coherence tomography (OCT in addition to ophthalmological examination preceeding the replacement therapy and at the 1st, 3rd and 6th months of treatment. The mean age of the patients included in the study were 40.58 ± 1.32 years. The thyroid hormone levels return to normal levels in all patients during the follow-up period, however the mean intraocular pressure (IOP revealed no significant change. The mean CCT was 538.05 ± 3.85 μ initially and demonstrated no statistically significant change as the anterior chamber volume, depth and angle measurements did. The mean C/D ratio was 0.29 ± 0.03 and the mean retinal thickness was 255.83 ± 19.49 μ initially and the treatment did not give rise to any significant change. The mean RNFL thickness was also stable during the control visits, so no statistically significant change was encountered. Conclusions Neither hypothyroidism, nor its replacement therapy gave rise to any change of IOP, CCT, anterior chamber parameters, RNFL, retinal thickness and C/D ratio.

  6. THE MOTOR

    DEFF Research Database (Denmark)

    Gammelgaard Nielsen, Anders

    2011-01-01

    MOTOR is the first assignment that students at Unit 1a of the School of Architecture are introduced to. The purpose of the assignment is to shake up the students and their preconceptions of what architec- ture is. This is done by introducing them to a working method that al- lows them to develop...

  7. Irritación ocular: Modelos alternativos

    Directory of Open Access Journals (Sweden)

    Raiza Vega Montalvo

    2001-12-01

    Full Text Available El ojo puede ser dañado accidentalmente por el uso de muchos productos de uso rutinario. Para facilitar la seguridad de los consumidores es necesario estimar el potencial de irritación ocular de estas sustancias químicas. Esta estimación está basada en los resultados obtenidos en el ensayo de Draize llevado a cabo en conejos. Sin embargo, avances en el desarrollo de la toxicología in vitro han permitido el uso de algunas alternativas para la evaluación del riesgo ocular; por lo que se presenta una revisión acerca de los diferentes métodos alternativos disponibles hasta el momento que permiten evaluar de una forma u otra los efectos tóxicos a nivel ocular.The eye may be accidentally damaged by many products of daily use. To guarantee the consumers’ safety it is necessary to estimate the eye irritation potential of these chemical substances. This estimation is based on the results obtained in the Draize rabbit eye irritation test. However, the advances attained in the development of in vitro toxicology have allowed the use of some alternatives to evaluate the ocular risk. Therefore, a review is made on the different alternative methods available up to now that make possible the evaluation in one way or another of the toxic effects at the ocular level.

  8. Ocular biomechanics study: current state and perspectives

    Directory of Open Access Journals (Sweden)

    S. Yu. Petrov

    2015-03-01

    Full Text Available Despite the fact that the eye represents a challenge for biomechanical research due to its size, over the last two decades, much data on ocular biomechanics were accumulated. Scleral and lamina cribrosa biomechanics contribute to our understanding of myopia and open-angle glaucoma; iris and trabecular meshwork biomechanics to that of angle-closure glaucoma; vitreous biomechanics to that of retinal detachment and ocular drug delivery; corneal biomechanics to that of keratoconus; and lens capsule biomechanics to that of cataract. This paper offers a general overview of recent advances in corneal, scleral, crystalline lens, and lamina cribrosa biomechanics and summarizes the results of experimental and clinical studies. Ocular biomechanics abnormalities affect etiology of many eye diseases. Ocular biomechanics plays an important role in the development of novel diagnostic methods, therapeutic and surgical procedures. Corneal biomechanics impacts etiology and pathogenesis of keratoconus as well as tonometry accuracy and explains corneal refractive surgery effect. Scleral biomechanics is associated with IOP and progressive myopia. Accommodative apparatus (ciliary body and crystalline lens is an important anatomic physiological structure. Recent studies uncovered the causes of agerelated loss of accommodation as a result of lens involution. Optic nerve head abnormalities due to IOP fluctuations are the key factor of glaucomatous neuropathy. They are directly associated with ocular biomechanics as well.

  9. Ocular biomechanics study: current state and perspectives

    Directory of Open Access Journals (Sweden)

    S. Yu. Petrov

    2015-01-01

    Full Text Available Despite the fact that the eye represents a challenge for biomechanical research due to its size, over the last two decades, much data on ocular biomechanics were accumulated. Scleral and lamina cribrosa biomechanics contribute to our understanding of myopia and open-angle glaucoma; iris and trabecular meshwork biomechanics to that of angle-closure glaucoma; vitreous biomechanics to that of retinal detachment and ocular drug delivery; corneal biomechanics to that of keratoconus; and lens capsule biomechanics to that of cataract. This paper offers a general overview of recent advances in corneal, scleral, crystalline lens, and lamina cribrosa biomechanics and summarizes the results of experimental and clinical studies. Ocular biomechanics abnormalities affect etiology of many eye diseases. Ocular biomechanics plays an important role in the development of novel diagnostic methods, therapeutic and surgical procedures. Corneal biomechanics impacts etiology and pathogenesis of keratoconus as well as tonometry accuracy and explains corneal refractive surgery effect. Scleral biomechanics is associated with IOP and progressive myopia. Accommodative apparatus (ciliary body and crystalline lens is an important anatomic physiological structure. Recent studies uncovered the causes of agerelated loss of accommodation as a result of lens involution. Optic nerve head abnormalities due to IOP fluctuations are the key factor of glaucomatous neuropathy. They are directly associated with ocular biomechanics as well.

  10. Frequency of Ocular Manifestation in Hemodialysis Patients

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    Eslami F

    2017-06-01

    Full Text Available Introduction: Chronic renal disease compromises of several renal involvements and several causative risk factors such as debates mellitus, hypertension, and old age. Ocular involvement seems to be related to chronic renal failure and hemodialysis as indicated by different studies. The aim of this study was the evaluation of prevalence of ocular manifestation in hemodialysis patients of Hamadan Besat hospital. Methods: This research was a cross sectional descriptive study, in which ocular signs in 74 hemodialysis patients, who referred to Besat hospital of Hamadan, Iran, during year 2015, were evaluated. Collected information related to patients included age, gender, dialysis duration, and background risk factors of chronic renal failure. All patients had been exanimated by an ophthalmologist. Results: Fifty percent of patients in the study were male and 50% were female. Average age of patients was 58.8 years and median duration of dialysis was 40.16 months. Mean visual acuity was 4.58 (of 10. Most common ocular manifestations were: macula abnormality (59.5%, cataract (56.7%, eye pain (56.7%, eye redness (52.7%, dry eyes (50%, and eyelid edema (43.2%, respectively. Conclusions: Hypertension and diabetes mellitus are the most common causes of chronic renal failure. The most common ocular manifestations were macular abnormality followed by cataract. According to high prevalence of these complications in hemodialysis patients, regular monitoring of patients for early detection and thus effective treatment seems to be necessary to improve their quality of life

  11. Impacts of Nanomedicines in Ocular Pharmacotherapy

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    Jaleh Barar

    2011-06-01

    Full Text Available Introduction: The integrity of the cells/tissues in anterior and/or posterior segments of the eye plays a crucial role in biofunctions of the vision. To maintain ocular homeostasis, selective restrictiveness of the ophthalmic membranes and barriers control must act on shuttling of biomolecules. Thus, not all attempts to apply de novo nanotechnology approaches for ocular pharmacotherapy have met with the same successes as those cited here in this review, and sometimes these novel technologies tools provoke a great deal of challenges and hurdles mainly because of functional presence of these barriers. Methods: Recent published articles related to application of ocular nanomedicines were reviewed and highlighted in this review article. Results: It seems the emergence of nanomedicines have arisen great hopes for ophthalmic pharmacotherapy, in which nanostructured medicines are expected to be able to cross the restrictive barriers of the eye. Although such fast inauguration of ocular nanomedicines will literally convey new challenges in the regulatory and translational processes, it will also grant a prolific platform from which many exciting, and yet unimagined, applications of biomedical nanotechnology will emerge for pharmacotherapy of the eye. Conclusion: This review provide recent advancements on ocular nanomedicines.

  12. The relationship between demodex and ocular discomfort.

    Science.gov (United States)

    Lee, Seok Hyun; Chun, Yeoun Sook; Kim, Jae Hoon; Kim, Eung Suk; Kim, Jae Chan

    2010-06-01

    To determine the correlative relationship between the prevalence of Demodex in eyelashes and the severity of ocular discomfort, by investigating the demographic epidemiology associated with Demodex. One hundred seventy patients underwent epilation of four eyelashes of each eye, and the number of Demodex was counted. The patients answered questionnaires about ocular surface discomfort and underwent ophthalmic examinations, including slit lamp, tear film breakup time (BUT), Schirmer test, and microbial culturing. The correlative relationship between the number of Demodex and these variable data was analyzed. Demodex was found in 120 (70%) of the 170 tested patients. Of 1360 eyelashes, 740 (54%) had Demodex. There was no significant difference in the prevalence of Demodex between males and females (P = 0.35). The number of Demodex showed significant positive correlations with increased age, ocular discomfort, and 1/BUT (P Demodex was significantly higher in patients with conjunctival papillary hypertrophy than in those without (P = 0.003). The presence or distribution of bacteria on eyelashes was similar between eyelids with and without Demodex. However, methicillin-resistant Staphylococcus aureus (MRSA) was detected more often on eyelids with Demodex, but this difference was not statistically significant. There is a strong correlation between the number of Demodex and the severity of ocular discomfort, suggesting that Demodex plays a pathogenic role in the ocular discomfort linked with aging.

  13. Complications of ocular paintball injuries in children.

    Science.gov (United States)

    Hargrave, S; Weakley, D; Wilson, C

    2000-01-01

    To evaluate the ocular complications of paintball injuries in children. The clinical course of four children with traumatic ocular paintball injuries was evaluated. All patients underwent a complete ocular examination. Their age, injuries sustained, surgical procedure(s) performed, presence of protective eyewear at the time of injury, and final visual outcome was assessed. The presence of directly related anterior and posterior segment abnormalities were also evaluated. Four boys sustained traumatic paintball injuries. Average patient age was 11.25 years (range: 10-12 years). None of the children were wearing ocular or facial protection at the time of the initial injury. All patients had hyphema and traumatic cataract, and some form of retinal pathology (vitreous hemorrhage, epiretinal membrane, retinal hemorrhage, and choroidal rupture). One child had a partial-thickness corneal laceration that did not require surgical intervention. All other patients underwent ophthalmic surgery. Final visual acuity was 20/30 or better in two patients, and 20/100 or worse in the others. The cause of decreased visual acuity in these children was directly related to macular pathology. Ocular injuries resulting from paintball impact are often severe and usually occur when the participants are not wearing eye protection or this protection becomes dislodged. Treatment of these injuries is sometimes limited to an attempt to salvage what remains of useful vision. Unfortunately, most of these sports-related injuries could have been prevented if patients wore adequate eye protection when involved in this sport.

  14. Effects of Volitional Spine Stabilization and Lower Extremity Fatigue on Trunk Control During Landing in Individuals With Recurrent Low Back Pain.

    Science.gov (United States)

    Haddas, Ram; Sawyer, Steven F; Sizer, Phillip S; Brooks, Toby; Chyu, Ming-Chien; James, C Roger

    2016-02-01

    Controlled laboratory study. Recurrent low back pain (LBP) and neuromuscular fatigue are independently thought to increase the risk of spine injury. Volitional preemptive abdominal contraction (VPAC) is thought to improve lumbar spine and pelvis control in individuals with recurrent LBP. The effects of VPAC on fatigued landing performance in individuals with recurrent LBP are unknown. To determine the effects of VPAC and lower extremity fatigue on trunk control during landing in a population of individuals with recurrent LBP. Thirty-two recurrent LBP (mean ± SD age, 21.2 ± 2.7 years) and 33 healthy (age, 20.9 ± 2.3 years) subjects performed 0.30-m drop-jump landings with and without VPAC and fatigue. Trunk, pelvis, and hip biomechanical and electromyographic variables were obtained using 3-D motion capture. Hypotheses were tested using analysis of variance. Volitional preemptive abdominal contraction resulted in significantly earlier muscle onsets across all muscles, with and without fatigue, in both groups (mean ± SD, 0.058 ± 0.019 seconds earlier; P≤.001) and altered lumbar lateral flexion (1.4° ± 14.8° greater right lateral flexion; P = .002). Fatigue significantly delayed muscle onsets (0.040 ± 0.014 seconds later; P≤.001) and altered pelvic obliquity (1.4° ± 11.0° greater; P≤.001) and trunk side flexion (2.0° ± 14.8° less; P≤.001). The recurrent LBP group exhibited delayed muscle onsets (0.039 ± 0.031 seconds later; P≤.004) and 4.2° less hip abduction at initial contact (P≤.008) in comparison to healthy controls. Volitional preemptive abdominal contraction decreases some of the detrimental effects of fatigue on landing biomechanics and thus may reduce spine injury risk in individuals with recurrent LBP.

  15. Ocular trauma injuries: a 1-year surveillance study in the University of Malaya Medical Centre, Malaysia. 2008.

    Science.gov (United States)

    Soong, Terrence Kwong-Weng; Koh, Alan; Subrayan, Visvaraja; Loo, Angela Voon Pei

    2011-12-01

    To describe the epidemiology of ocular injuries presenting to the University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia. Prospective analysis of all ocular trauma injuries presenting to the Department of Ophthalmology in UMMC from 1 January 2008 to 31 December 2008. A total of 603 eyes of 546 patients were recruited for the study. All patients presenting to the department with ocular trauma injuries were assessed by an ophthalmologist. Data on the type and source of injury, demographic profile of the patients, and clinical presentation were documented using a uniform and validated datasheet. Among eye injury cases, 481 patients (88.1%) were male, with a male-to-female ratio of 7.4:1. Of the patients, 412 (75.5%) were Malaysian while the remaining 134 (24.5%) were of non-Malaysian nationality. The average age was 31.5 years (range 1-81 years). A total of 238 injured eyes (43.6%) were work-related. The common sources of eye trauma include the use of high-powered tools (30.8%), motor vehicle accident (23.1%), and domestic accidents (17.7%). Only six patients (2.5%) reported to having used eye protective device (EPD) at time of their work-related injuries. A major cause of preventable ocular injuries in Malaysia was work-related trauma. Ocular injuries can be reduced by the use of eye protection devices and the implementation of appropriate preventive strategies to address each risk factor. Effective training is an integral part of occupational safety and health, which should be made mandatory at the workplace. In addition, there should be a continual assessment of safety and health issues at the workplace. A long-term database of all ocular injuries in Malaysia is recommended, to aid research on a larger scale and the development of new preventive strategies for ocular injuries.

  16. Efficiency of the program of correction of emotional-volitional sphere of swimmers with violations of intellect on a test 4х50 m.

    Directory of Open Access Journals (Sweden)

    Babich Nataliia Leonidovna

    2011-09-01

    Full Text Available The comparative analysis of results of implementation of test is resulted 4х50 m by swimmers with violations of mental development before and after introduction of the experimental program of correction emotionally of volitional sphere of such sportsmen. Grounded expedience of the use of test 4х50 m as one of criteria of estimation of ability of swimmers to mobilization and display of conations on a background a fatigue. It is well-proven that the experimental program positively influenced on the dynamics of stabilizing of results of swimming of the 4 test cuttings-off in the conditions of hard rest on a background a fatigue.

  17. Development and validation of a questionnaire assessing volitional competencies to enhance the performance of physical activities in chronic low back pain patients

    Directory of Open Access Journals (Sweden)

    Duplan Bernard

    2011-05-01

    Full Text Available Abstract Background Motivation has long been emphasized as the most important determinant of action. However, there is a substantial gap between people's goals and their attainment. Patients may be motivated and yet unable to take action if their volitional competencies are insufficient. One of the important tasks of volition is goal-maintenance. Research has stressed the importance of a volitional tool, the implementation intentions. Implementation intentions indicate where, when, and how the action leading to the goal will be performed. Forming implementation intentions favours the execution of goal-directed efforts, and reinforces the relationship between intentions and behaviours. Results from various studies clearly suggest that volitional competencies and implementation intentions could play a role in low back pain (LBP patients. However, there is at present no questionnaire allowing assessing the capacity of implementation intentions of physical activities in LBP patients. Methods/Design This study will develop such a questionnaire, using a 3-step approach. A first qualitative step to build categories and generate items; 30 patients suffering chronic LBP will be invited to participate in semi-structured interviews; verbatim and derived items will then be submitted to a panel of experts, using a Delphi method; a second quantitative step to examine the properties of items, and determine the factorial structure of the questionnaire; 100 patients suffering chronic LBP will be recruited to respond to this phase; and third, preliminary psychometric analyses (item-scale correlations, construct validity, reliability; 180 chronic LBP patients will be recruited for this phase of the study. The relationships between implementation intentions and variables affecting physical activity on chronic LBP patients, i.e. pain, physical capacities, fear-avoidance beliefs, kinesiophobia, work status, and level of physical activity will be considered

  18. Recent Advances in Ocular Drug Delivery Systems

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    Shinobu Fujii

    2011-01-01

    Full Text Available Transport of drugs applied by traditional dosage forms is restricted to the eye, and therapeutic drug concentrations in the target tissues are not maintained for a long duration since the eyes are protected by a unique anatomy and physiology. For the treatment of the anterior segment of the eye, various droppable products to prolong the retention time on the ocular surface have been introduced in the market. On the other hand, direct intravitreal implants, using biodegradable or non-biodegradable polymer technology, have been widely investigated for the treatment of chronic vitreoretinal diseases. There is urgent need to develop ocular drug delivery systems which provide controlled release for the treatment of chronic diseases, and increase patient’s and doctor’s convenience to reduce the dosing frequency and invasive treatment. In this article, progress of ocular drug delivery systems under clinical trials and in late experimental stage is reviewed.

  19. Ocular rhinosporidiosis presenting as recurrent chalazion.

    Science.gov (United States)

    Mukhopadhyay, Somnath; Shome, Subrata; Bar, Prasenjit Kumar; Chakrabarti, Amit; Mazumdar, Swati; De, Avisek; Sadhukhan, Kaushik; Bala, Bivas

    2015-10-01

    Rhinosporidiosis, a granulomatous disease caused by Rhinosporidium seeberi, is widely prevalent in Sri Lanka and southern parts of India. Besides the eye, the lacrimal passage and nasal cavity are affected. The most common ocular involvement is a subconjunctival bleeding mass. Our case, a 9-year-old girl from a rural background with a history of pond water bathing, presented with a marginal chalazion involving the left lower lid. She had a history of chalazion involving the same site three months earlier which was managed by incision and curettage. A decision of surgical exploration was made and the evacuated mass was examined histologically showing evidence of rhinosporidiosis. This type of clinical presentation for ocular rhinosporidiosis (as recurrent chalazion) has not been reported earlier in the literature. This case emphasises that the clinicians from this part of the world must consider ocular rhinosporidiosis as differential diagnosis in cases with recurrent chalazion especially in a rural background with a habit of pond water bathing.

  20. Ocular manifestations of tick-borne diseases.

    Science.gov (United States)

    Raja, Harish; Starr, Matthew R; Bakri, Sophie J

    Tick-borne illnesses are a significant disease burden worldwide. Diagnosis is challenging and requires a high level of clinical suspicion. Ocular manifestations reported in association with tick-borne disease are mostly as case reports and small case series because of the relative infrequency with which they occur; however, given the global nature of health care and increase in travel in the 21st century, it is important for ophthalmologists to be aware of ocular manifestations of these diseases because early diagnosis may reduce morbidity and mortality. Here, we review of the literature of tick-borne diseases with reported ophthalmic findings. All known human tick-borne diseases are discussed, including a brief description of the causative agent, region of endemicity, vector, systemic symptoms, and any reported eye findings. When possible, we also address the strength of the evidence for these ocular associations. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Lymphocyte transformation in presumed ocular histoplasmosis

    Energy Technology Data Exchange (ETDEWEB)

    Ganley, J.P.; Nemo, G.J.; Comstock, G.W.; Brody, J.A.

    1981-08-01

    Lymphocytes from individuals with inactive macular disciform lesions of presumed ocular histoplasmosis challenged with three histoplasmin antigens incorporated tritiated thymidine at a significantly higher rate than histoplasmin-stimulated lymphocytes of matched control and peripheral scar groups. This finding is consistent with the etiologic association of the disciform ocular syndrome and previous systemic infection with Histoplasma capsulatum. The disciform group had a higher mean response than the other two groups to pokeweed mitogen but not to phytohemagglutinin and had higher mean counts per minute to the specific antigens Toxoplasma gondii, Blastomyces dermatitidis, Cryptococcus neoformans, Mycobacterium tuberculosis, M battery, and M gaus, but not to Candida albicans. These data would suggest that individuals with the disciform lesion of presumed ocular histoplasmosis have a hyperreactive cellular immune response; this response may play an important role in the development of the disciform.

  2. Ocular Fundus Photography as an Educational Tool.

    Science.gov (United States)

    Mackay, Devin D; Garza, Philip S

    2015-10-01

    The proficiency of nonophthalmologists with direct ophthalmoscopy is poor, which has prompted a search for alternative technologies to examine the ocular fundus. Although ocular fundus photography has existed for decades, its use has been traditionally restricted to ophthalmology clinical care settings and textbooks. Recent research has shown a role for nonmydriatic fundus photography in nonophthalmic settings, encouraging more widespread adoption of fundus photography technology. Recent studies have also affirmed the role of fundus photography as an adjunct or alternative to direct ophthalmoscopy in undergraduate medical education. In this review, the authors examine the use of ocular fundus photography as an educational tool and suggest future applications for this important technology. Novel applications of fundus photography as an educational tool have the potential to resurrect the dying art of funduscopy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. Hutchinson's sign as a marker of ocular involvement in HIVpositive ...

    African Journals Online (AJOL)

    Journal Home > Vol 100, No 3 (2010) > ... We examined the sensitivity of Hutchinsonfs sign as an indicator of ocular involvement in a consecutive ... Neither age nor CD4 count had predictive value for ocular involvement. ... Article Metrics.

  4. Ocular trauma: A tertiary hospital experience from Oman

    Directory of Open Access Journals (Sweden)

    Haitham H Al-Mahrouqi

    2017-01-01

    CONCLUSION: Ocular trauma is a common presentation at Al-Nahdha Hospital. Although the majority of trauma cases were minor without any resultant visual disability, OGI could have been prevented with better ocular protection in the workplace.

  5. Eye cosmetic usage and associated ocular comfort.

    Science.gov (United States)

    Ng, Alison; Evans, Katharine; North, Rachel; Purslow, Christine

    2012-11-01

    Eye cosmetics usage is commonplace and whilst some products such as eyeliner are applied with close proximity to the ocular surface, there is little knowledge of the short- and long-term ocular effects of eye cosmetic formulations. This study aimed to investigate the use of eye cosmetics and identify any relationships between ocular comfort and cosmetic usage. Results were collated from an online survey comprising 23 questions that recorded demographics, Ocular Surface Disease Index (OSDI) score, extent and range of eye cosmetic use and perceived comfort differences with and without eye cosmetics. The 1360 female respondents (median age 25, interquartile range 20-34 years) completed the survey; 83% reported using eye cosmetics regularly (≥ 3 times per week) with mascara being most commonly used. Fifty three per cent used at least three different eye cosmetics products regularly. OSDI scores of cosmetics users were similar to non-users (p = 0.083), but perceived comfort was greater when cosmetics were not used (p cosmetics users (use of products cosmetics were used. Median OSDI scores suggested a trend towards reduced comfort amongst eyeliner users (p = 0.07) although frequency and type of cosmetic products used did not appear to influence OSDI scores. This study shows the use of multiple eye cosmetics is extensive and associated with the perception of ocular discomfort. With such widespread use of these products, more research is required to assess the effect on the ocular surface and tear film, which may be underestimated. Ophthalmic & Physiological Optics © 2012 The College of Optometrists.

  6. Ocular disorders among workers exposed to mercury.

    Science.gov (United States)

    Gabal, M S; Raslan, O A

    1995-01-01

    Mercury vapor exposed workers may show ocular changes, as well as other systems affection. A sample of 84 workers in preparing mercury fulminate were examined for conjunctival corneal and lenticular manifestation of long duration exposure, together with mercury urinary output. Lens changes were found in 50% of the involved workers while keratopathy as recorded in 34.5% of them. No statistically significant association was found between the occurrence of eye lesions and levels of urinary elimination of mercury. These results suggest local absorption of this element is most probably the underlying cause of ocular affection.

  7. Ocular dominance and visual function testing

    OpenAIRE

    D. Lopes-Ferreira; Neves, H; A. Queiros; Faria-Ribeiro, M.; Peixoto-de-Matos, S. C.; J. M. González-Méijome

    2013-01-01

    To show the distribution of ocular dominance as measured with sensory and eye sighting methods and its potential relationship with high and low contrast LogMAR visual acuity in presbyopic subjects. Method. Forty-four presbyopes (48.5 ± 3.5 years) participated in this study. Ocular dominance was determined by eye sighting (hole-in-card) and sensorial (+1.50 D lens induced blur) methods. According to the dominance detected with each method (RE: right eye or LE: left eye), patients were classifi...

  8. Physiopathology and recording techniques of ocular movements

    OpenAIRE

    L. Gila; Villanueva, A; Cabeza, R

    2009-01-01

    En el control de la motilidad ocular intervienen varios sistemas funcionales. Los reflejos vestíbulo-oculares y optocinéticos son respuestas automáticas para compensar los movimientos de la cabeza y del entorno visual y poder estabilizar la imagen retiniana sobre un determinado punto de fijación. Los movimientos sacádicos son rápidos desplazamientos de la fijación de un punto a otro del campo visual. Los movimientos de persecución lenta consisten en el seguimiento de estímulos móviles con la ...

  9. New Developments in Ocular Surface Squamous Neoplasia

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    Ayşe Yağcı

    2014-09-01

    Full Text Available Ocular surface squamous neoplasia originates from conjunctiva epithelium and covers a broad spectrum of disease ranging from dysplasia to squamous cell carcinoma. Clinical features may vary from case to case. Traditional treatment of excision with no-touch technique combined with adjuvant therapies because of high recurrence rate. Main adjuvant treatments are cryotherapy and chemotherapy. In this review, clinical forms, differential diagnosis, American Joint Committee on Cancer classification and recent approaches to the management of ocular surface squamous dysplasia were described. (Turk J Ophthalmol 2014; 44: Supplement 8-14

  10. Pinwheel Stabilization by Ocular Dominance Segregation

    Science.gov (United States)

    Reichl, Lars; Löwel, Siegrid; Wolf, Fred

    2009-05-01

    We present an analytical approach for studying the coupled development of ocular dominance and orientation preference columns. Using this approach we demonstrate that ocular dominance segregation can induce the stabilization and even the production of pinwheels by their crystallization in two types of periodic lattices. Pinwheel crystallization depends on the overall dominance of one eye over the other, a condition that is fulfilled during early cortical development. Increasing the strength of intermap coupling induces a transition from pinwheel-free stripe solutions to intermediate and high pinwheel density states.

  11. Genetics in ocular inflammation--basic principles.

    Science.gov (United States)

    Wallace, G R; Niemczyk, E

    2011-02-01

    The ability to identify individuals at risk of ocular disease, or to determine the potential severity of disease or response to therapy is the current focus of much research. These studies are being led by genetic analysis of individuals to determine associations with alterations in gens that may explain manifestations of particular diseases. In this review we consider the basic principles behind genetic studies in general and of ocular disease in particular. We address the methodologies being utilised, and the results derived so far. The potential and pitfalls of such studies are relevant to the concept of personalised medicine and better defined clinical trials.

  12. Post-trabeculectomy ocular biometric changes.

    Science.gov (United States)

    Pakravan, Mohammad; Alvani, Azam; Esfandiari, Hamed; Ghahari, Elham; Yaseri, Mehdi

    2017-03-01

    Trabeculectomy is the most common surgical procedure for the management of glaucoma, which may significantly influence ocular biometry. Axial length and anterior chamber depth tend to decrease, while crystalline lens and choroidal thickness increase post-operatively. An increase in with-the-rule astigmatism is also observed after the procedure. Such biometric changes affect intraocular lens power calculation even years after the procedure. Non-contact biometric methods and postponing cataract surgery after trabeculectomy could reduce calculation errors associated with surgically induced alterations in ocular biometrics. © 2016 Optometry Australia.

  13. Emerging ocular biomarkers of Alzheimer disease.

    Science.gov (United States)

    van Wijngaarden, Peter; Hadoux, Xavier; Alwan, Mostafa; Keel, Stuart; Dirani, Mohamed

    2017-01-01

    Interest in reliable biomarkers of Alzheimer disease, the leading cause of dementia, has been fuelled by challenges in diagnosing the disease and monitoring disease progression as well as the response to therapy. A range of ocular manifestations of Alzheimer disease, including retinal and lens amyloid-beta accumulation, retinal nerve fiber layer loss, and retinal vascular changes, have been proposed as potential biomarkers of the disease. Herein, we examine the evidence regarding the potential value of these ocular biomarkers of Alzheimer disease. © 2016 Royal Australian and New Zealand College of Ophthalmologists.

  14. Alterações oculares em pacientes com tuberculose Ocular manifestation in patients with tuberculosis

    Directory of Open Access Journals (Sweden)

    Simone Ribeiro Araújo de Almeida

    2006-04-01

    Full Text Available OBJETIVO: Analisar os achados clínicos da tuberculose ocular e seus aspectos epidemiológicos. MÉTODOS: Foram revisados prontuários médicos de pacientes que foram atendidos no Departamento de Oftalmologia - setor de Uveíte e AIDS da Unifesp-EPM, São Paulo, Brasil, entre janeiro de 1999 e julho de 2002 e que tiveram diagnóstico de tuberculose ocular. Foram inclusos os pacientes que apresentaram PPD forte reator, epidemiologia positiva para tuberculose e lesão ocular que melhorou com tratamento específico. RESULTADOS: Foram analisados prontuários médicos de 17 pacientes, sendo 12 (70,6% do sexo feminino. A idade média foi de 54 (24-84 anos. O tempo médio entre o início dos sintomas e a primeira consulta foi de 100 dias. Os achados oculares foram inespecíficos nesta ocasião mas prevaleceram as alterações de segmento anterior e 41% dos pacientes apresentavam sinais de tuberculose sistêmica. Alterações como glaucoma, descolamento de retina e hemorragia vítrea foram responsáveis pela redução da acuidade visual. CONCLUSÃO: Embora pouco prevalente, a tuberculose ocular apresenta morbidade elevada. A inespecificidade da apresentação clínica da doença ocular pode atrasar o seu diagnóstico.PURPOSE: To analyze clinical findings of ocular tuberculosis and its epidemiological features. METHODS: Were reviewed clinical files of patients who attended the Ophthalmology - Uveitis and AIDS sector of UNIFESP-EPM, São Paulo, Brazil between January 1999 and July 2002 and had a diagnosis of ocular tuberculosis. Patients who had Mantoux test higher than 10 mm, epidemiological history of tuberculosis and ocular findings that improved after specific treatment were included. RESULTS: Seventeen medical files were analyzed, of those, 12 (70,6% were females. The mean age was 54 (24-84 years. The average time between symptoms and diagnosis was 100 days. Ocular findings at the first interview were multiple but most were at the anterior segment of

  15. Ocular manifestations and outcome of treatment of Stevens-Johnson ...

    African Journals Online (AJOL)

    Final visual acuity depended on presenting visual acuity, how early in the disease patients presented, degree of inflammation and the degree of ocular surface cicatrisation. Conclusion: Ocular involvement in SJS results in widely differing degrees of ocular disability. Management involves medications and surgery.

  16. 21 CFR 886.4360 - Ocular surgery irrigation device.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ocular surgery irrigation device. 886.4360 Section... (CONTINUED) MEDICAL DEVICES OPHTHALMIC DEVICES Surgical Devices § 886.4360 Ocular surgery irrigation device. (a) Identification. An ocular surgery irrigation device is a device intended to be suspended over the...

  17. Motor dexterity and strength depend upon integrity of the attention-control system.

    Science.gov (United States)

    Rinne, Paul; Hassan, Mursyida; Fernandes, Cristina; Han, Erika; Hennessy, Emma; Waldman, Adam; Sharma, Pankaj; Soto, David; Leech, Robert; Malhotra, Paresh A; Bentley, Paul

    2018-01-16

    Attention control (or executive control) is a higher cognitive function involved in response selection and inhibition, through close interactions with the motor system. Here, we tested whether influences of attention control are also seen on lower level motor functions of dexterity and strength-by examining relationships between attention control and motor performance in healthy-aged and hemiparetic-stroke subjects ( n = 93 and 167, respectively). Subjects undertook simple-tracking, precision-hold, and maximum force-generation tasks, with each hand. Performance across all tasks correlated strongly with attention control (measured as distractor resistance), independently of factors such as baseline performance, hand use, lesion size, mood, fatigue, or whether distraction was tested during motor or nonmotor cognitive tasks. Critically, asymmetric dissociations occurred in all tasks, in that severe motor impairment coexisted with normal (or impaired) attention control whereas normal motor performance was never associated with impaired attention control (below a task-dependent threshold). This implies that dexterity and force generation require intact attention control. Subsequently, we examined how motor and attention-control performance mapped to lesion location and cerebral functional connectivity. One component of motor performance (common to both arms), as well as attention control, correlated with the anatomical and functional integrity of a cingulo-opercular "salience" network. Independently of this, motor performance difference between arms correlated negatively with the integrity of the primary sensorimotor network and corticospinal tract. These results suggest that the salience network, and its attention-control function, are necessary for virtually all volitional motor acts while its damage contributes significantly to the cardinal motor deficits of stroke. Copyright © 2018 the Author(s). Published by PNAS.

  18. Altered functional connectivity links in neuroleptic-naïve and neuroleptic-treated patients with schizophrenia, and their relation to symptoms including volition

    Directory of Open Access Journals (Sweden)

    Weidan Pu

    2014-01-01

    Full Text Available In order to analyze functional connectivity in untreated and treated patients with schizophrenia, resting-state fMRI data were obtained for whole-brain functional connectivity analysis from 22 first-episode neuroleptic-naïve schizophrenia (NNS, 61 first-episode neuroleptic-treated schizophrenia (NTS patients, and 60 healthy controls (HC. Reductions were found in untreated and treated patients in the functional connectivity between the posterior cingulate gyrus and precuneus, and this was correlated with the reduction in volition from the Positive and Negative Symptoms Scale (PANSS, that is in the willful initiation, sustenance, and control of thoughts, behavior, movements, and speech, and with the general and negative symptoms. In addition in both patient groups interhemispheric functional connectivity was weaker between the orbitofrontal cortex, amygdala and temporal pole. These functional connectivity changes and the related symptoms were not treated by the neuroleptics. Differences between the patient groups were that there were more strong functional connectivity links in the NNS patients (including in hippocampal, frontal, and striatal circuits than in the NTS patients. These findings with a whole brain analysis in untreated and treated patients with schizophrenia provide evidence on some of the brain regions implicated in the volitional, other general, and negative symptoms, of schizophrenia that are not treated by neuroleptics so have implications for the development of other treatments; and provide evidence on some brain systems in which neuroleptics do alter the functional connectivity.

  19. Management outcome of ocular surface conjunctival neoplasia ...

    African Journals Online (AJOL)

    Background: Ocular surface squamous neoplasia (OSSN)are aspectrum of lesions that arise from the squamous epithelium of the conjunctiva and cornea. They form the most frequent indication for orbital exenteration in Korle-bu Teaching Hospital, Accra. Poor management of early lesions leads to high rates of tumour ...

  20. [Improving the quality of glass ocular prostheses].

    Science.gov (United States)

    Nadareĭshvili, T B; Pakhomova, T S; Labutina, L V; Kachko, A L

    1979-01-01

    A critical analysis has been attempted of the current state-of-the-art in studying seleno-cadmium ruby glasses applicable for glass ocular prosthesis production. Better quality of these prostheses can be achieved by both the refinement of the ruby glass composition and by its strengthening (hardening) through proper methods.

  1. Ocular malignant lymphoma. A clinical pathological study

    Directory of Open Access Journals (Sweden)

    Panda A

    1987-01-01

    Full Text Available Eleven histologically proved cases of ocular malignant lymphoma diagnosed and managed during the year 1974-81 are reported. The follow-up period ranges from 2-7 years. The difficulties in diagnosis, treatment and prognosis are discussed.

  2. Ocular aberrations and wavefront aberrometry: A review

    Directory of Open Access Journals (Sweden)

    Holly A. Unterhorst

    2015-03-01

    Full Text Available Wavefront aberrations can be described as deviations of the wavefront exiting the eye froma reference wavefront that is aberration free and diffraction limited. Ocular aberrations canbe sub-categorised as lower and higher order aberrations. Ocular aberrations have promptedinterest amongst the ocular healthcare community owing to their influences on the visualfunctioning of patients as well as differences observed in ocular aberrations through the useof refractive surgery both pre- and post-operatively. Uncompensated refractive error remainsone of the most common reasons for which patients consult optometrists. Compensationof refractive error, or lower order aberrations, has become a routine procedure during anoptometric examination. However, there are some patients who experience visual symptomseven after their refractive errors have been compensated via spectacles or contact lenses.Higher-order aberrations may be the source of these visual disturbances. Refractive surgeryhas been found to influence and even induce various changes in higher-order aberrationspost-operatively, which in turn has led to increased interest in wavefront aberrations and howthe measurement of these aberrations can improve diagnosis and treatment within optometryand ophthalmology.

  3. Surgical rehabilitation following severe ocular burns.

    Science.gov (United States)

    Tuft, S J; Shortt, A J

    2009-10-01

    Chemical and thermal burns can cause devastating injuries to the anterior segment. The consequences of alkali injuries are notoriously severe due to the rapid penetration of these agents into the ocular tissues. Denaturation of tissue, inflammation, and scarring leads to loss of function. An understanding of the pathogenesis of tissue damage has lead to a rational approach to treatment. Emergency irrigation of the eye is essential and there is a 'window of opportunity' during the first 7-10 days after injury when medical treatment can significantly limit the potentially blinding consequences. The acute injury is followed by early and late reparative phases during which the prognosis can be further improved by surgical intervention. Early surgical intervention is targeted at protecting the ocular surface and encouraging re-epithelisation. Later, surgical treatments are directed at ocular surface reconstruction and restoration of vision. However, before any attempt is made at surface reconstruction, the ocular surface environment must be optimised by division of symblepharon, and correction of lid deformity and trichiasis. If there is conjunctivalisation of the corneal surface, limbal stem cell transplantation can restore a corneal epithelial cell phenotype, and transplantation of in vitroamplified corneal epithelial stem cells has been developed as an alternative to keratolimbal transfer techniques. Keratoplasty and cataract surgery may then be necessary to clear the visual axis. Finally, keratoprosthesis is an option for the most severely damaged eyes.

  4. Treatment of acute ocular chemical burns.

    Science.gov (United States)

    Sharma, Namrata; Kaur, Manpreet; Agarwal, Tushar; Sangwan, Virender S; Vajpayee, Rasik B

    2017-09-19

    Ocular chemical burns are an ophthalmic emergency and are responsible for 11.5%-22.1% of ocular injuries. Immediate copious irrigation is universally recommended in acute ocular burns to remove the offending agent and minimize damage. Conventional medical therapy consists of the use of agents that promote epithelialization, minimize inflammation, and prevent cicatricial complications. Biological fluids such as autologous serum, umbilical cord blood serum, platelet-rich plasma, and amniotic membrane suspension are a rich source of growth factors and promote healing when used as adjuncts to conventional therapy. Surgical treatment of acute ocular burns includes the debridement of the necrotic tissue, application of tissue adhesives, tenoplasty, and tectonic keratoplasty. Amniotic membrane transplantation is a novel surgical treatment that is increasingly being used as an adjunct to conventional treatment to promote epithelial healing, minimize pain, and restore visual acuity. Various experimental treatments that aim to promote wound healing and minimize inflammation are being evaluated such as human mesenchymal and adipose stem cells, beta-1,3 glucan, angiotensin-converting enzyme inhibitors, cultivated fibroblasts, zinc desferrioxamine, antifibrinolytic agents, antioxidants, collagen cross-linking, and inhibitors of corneal neovascularization. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Myopic anisometropia: ocular characteristics and aetiological considerations.

    Science.gov (United States)

    Vincent, Stephen J; Collins, Michael J; Read, Scott A; Carney, Leo G

    2014-07-01

    Anisometropia represents a unique example of ocular development, where the two eyes of an individual, with an identical genetic background and seemingly subject to identical environmental influences, can grow asymmetrically to produce significantly different refractive errors. This review provides an overview of the research examining myopic anisometropia, the ocular characteristics underlying the condition and the potential aetiological factors involved. Various mechanical factors are discussed, including corneal structure, intraocular pressure and forces generated during near work that may contribute to development of anisomyopia. Potential visually guided mechanisms of unequal ocular growth are also explored, including the influence of astigmatism, accommodation, higher-order aberrations and the choroidal response to altered visual experience. The association between binocular vision, ocular dominance and asymmetric refraction is also considered, along with a review of the genetic contribution to the aetiology of myopic anisometropia. Despite a significant amount of research into the biomechanical, structural and optical characteristics of anisometropic eyes, there is still no unifying theory, which adequately explains how two eyes within the same visual system grow to different endpoints. © 2014 The Authors. Clinical and Experimental Optometry © 2014 Optometrists Association Australia.

  6. Ocular Lens Implantation In Benin City, Nigeria

    African Journals Online (AJOL)

    Intra ocular lens implantation is a relatively new surgical procedure in developing countries, although it has been the norm in developed countries for over three decades. It is carried out during cataract surgery for the purpose of aphakic correction. The aim of the study was to assess the level of awareness of the general ...

  7. Orbito-Ocular Teratoma: A Case Report

    African Journals Online (AJOL)

    and retroperitoneal regions of the body.1. Teratomas arising from the head and neck region are uncommon.4 We report a case of orbito-ocular teratoma in an infant. Case Report. A seventeen day-old baby ... intestinal glands and neural tissue with retinoblasts showing severe anaplasia. There was local infiltration and foci ...

  8. Ocular complications of malaria treatment | Nwosu | Nigerian ...

    African Journals Online (AJOL)

    Malaria is endemic in Nigeria. With the emergence of chloroquine resistance various modes of treatment including parenteral quinine are employed with consequent untoward effects. This article reports two cases of severe ocular toxicity, including mimicry of intracranial space‑occupying lesion, from treatment of malaria ...

  9. Fabrication and characterization of porous hydroxyapatite ocular ...

    Indian Academy of Sciences (India)

    Unknown

    areas of medicine (Aoki et al 1987; Grote 1987; Shin et al 1992) also. The use of hydroxyapatite as an ocular .... the experimental error, throughout the whole process of fabrication. The median particle size of HAp powder used ... per medication and resolution took place within the 12th post-operative day (figures 9 a–d).

  10. DNA nanoparticles as ocular drug delivery platform

    NARCIS (Netherlands)

    de Vries, Jan Willem

    2015-01-01

    The field of DNA nanotechnology has progressed rapidly in recent years and now offers facile fabrication of a large variety of nanostructures of different shapes and geometries. In this thesis, short nucleic acid sequences are functionalized with hydrophobic units to form the basis of an ocular drug

  11. Evolution of the vestibulo-ocular system

    Science.gov (United States)

    Fritzsch, B.

    1998-01-01

    The evolutionary and developmental changes in the eye muscle innervation, the inner ear, and the vestibulo-ocular reflex are examined. Three eye muscle patterns, based on the innervation by distinct ocular motoneurons populations, can be identified: a lamprey, an elasmobranch, and a bony fish/tetrapod pattern. Four distinct patterns of variation in the vestibular system are described: a hagfish pattern, a lamprey pattern, an elasmobranch pattern, and a bony fish/tetrapod pattern. Developmental data suggest an influence of the hindbrain on ear pattern formation, thus potentially allowing a concomitant change of eye muscle innervation and ear variation. The connections between the ear and the vestibular nuclei and between the vestibular nuclei and ocular motoneurons are reviewed, and the role of neurotrophins for pattern specification is discussed. Three patterns are recognized in central projections: a hagfish pattern, a lamprey pattern, and a pattern for jawed vertebrates. Second-order connections show both similarities and differences between distantly related species such as lampreys and mammals. For example, elasmobranchs lack an internuclear system, which is at best poorly developed in lampreys. It is suggested that the vestibulo-ocular system shows only a limited degree of variation because of the pronounced functional constraints imposed on it.

  12. The ocular complications of an envenomous snakebite

    African Journals Online (AJOL)

    2012-07-10

    Jul 10, 2012 ... A snakebite constitutes a common acute medical emergency and has several systemic and even ocular consequences. According to Patil et al,1 the importance of this public health problem has largely been ignored by medical science. There are approximately 3 000 snake species worldwide, of which ...

  13. Síndrome isquémico ocular Ocular ischemic syndrome

    Directory of Open Access Journals (Sweden)

    Ailén Garcés Fernández

    2010-01-01

    Full Text Available El síndrome isquémico ocular es caracterizado por síntomas y signos oculares secundarios a la estenosis severa y prolongada ipsilateral de la arteria carótida interna extracraneal o de la arteria carótida común, ocasionalmente, se ha asociado a la oclusión de la arteria oftálmica. En general, se considera un diagnóstico poco usual y constituye la tercera causa más común de glaucoma neovascular con pobre pronóstico visual. Hallazgos oculares incluyen disminución progresiva de la visión, inflamación del segmento anterior, neovascularización del iris y del ángulo iridocorneal, glaucoma neovascular y retinopatía por hipoperfusión periférica. Describimos un paciente con severa estenosis carotídea ipsilateral y disminución progresiva de la visión por la isquemia ocular. Se realiza una revisión sobre el manejo de esta condición tan controversial.Ocular ischemic syndrome is characterized by ocular symptoms and signs that are secondary to prolonged and severe ipsilateral stenosis of extracranial internal carotid artery or of the common carotid artery; occasionally, ipsilateral ophthalmic artery obstruction can also be responsible. It is generally considered as an unusual diagnosis, and the 3rd most common cause in neovascular glaucoma with poor visual prognosis. Ocular findings include gradual onset of decreased vision, inflammation of the anterior segment, iris and iridocorneal angle neovascularization, neovascular glaucoma and peripheral hypoperfusion retinopathy. Here is a patient with l severe ipsilateral carotid stenosis and progressive visual loss due to ocular ischemia. A literature review on the best management of this so controversial condition was made.

  14. Systematic analysis of ocular trauma by a new proposed ocular trauma classification

    Directory of Open Access Journals (Sweden)

    Bhartendu Shukla

    2017-01-01

    Full Text Available Purpose: The current classification of ocular trauma does not incorporate adnexal trauma, injuries that are attributable to a nonmechanical cause and destructive globe injuries. This study proposes a new classification system of ocular trauma which is broader-based to allow for the classification of a wider range of ocular injuries not covered by the current classification. Methods: A clinic-based cross-sectional study to validate the proposed classification. We analyzed 535 cases of ocular injury from January 1, 2012 to February 28, 2012 over a 4-year period in an eye hospital in central India using our proposed classification system and compared it with conventional classification. Results: The new classification system allowed for classification of all 535 cases of ocular injury. The conventional classification was only able to classify 364 of the 535 trauma cases. Injuries involving the adnexa, nonmechanical injuries and destructive globe injuries could not be classified by the conventional classification, thus missing about 33% of cases. Conclusions: Our classification system shows an improvement over existing ocular trauma classification as it allows for the classification of all type of ocular injuries and will allow for better and specific prognostication. This system has the potential to aid communication between physicians and result in better patient care. It can also provide a more authentic, wide spectrum of ocular injuries in correlation with etiology. By including adnexal injuries and nonmechanical injuries, we have been able to classify all 535 cases of trauma. Otherwise, about 30% of cases would have been excluded from the study.

  15. Platysma motor branch transfer in brachial plexus repair: report of the first case

    Directory of Open Access Journals (Sweden)

    Bertelli Jayme

    2007-05-01

    Full Text Available Abstract Background Nerve transfers are commonly employed in the treatment of brachial plexus injuries. We report the use of a new donor for transfer, the platysma motor branch. Methods A patient with complete avulsion of the brachial plexus and phrenic nerve paralysis had the suprascapular nerve neurotized by the accessory nerve, half of the hypoglossal nerve transferred to the musculocutaneous nerve, and the platysma motor branch connected to the medial pectoral nerve. Results The diameter of both the platysma motor branch and the medial pectoral nerve was around 2 mm. Eight years after surgery, the patient recovered 45° of abduction. Elbow flexion and shoulder adduction were rated as M4, according to the BMC. There was no deficit after the use of the above-mentioned nerves for transfer. Volitional control was acquired for independent function of elbow flexion and shoulder adduction. Conclusion The use of the platysma motor branch seems promising. This nerve is expendable; its section led to no deficits, and the relearning of motor control was not complicated. Further anatomical and clinical studies would help to clarify and confirm the usefulness of the platysma motor branch as a donor for nerve transfer.

  16. Epidemiological aspects of ocular superglue injuries.

    Science.gov (United States)

    Tabatabaei, Seyed Ali; Modanloo, Shokoufeh; Ghiyasvand, Arezoo Mohammadkhani; Pouryani, Abolghasem; Soleimani, Mohammad; Tabatabaei, Seyed Mehdi; Pakrah, Ahmad Reza; Masarat, Hamideh

    2016-01-01

    To report the frequency, associated risk factors and characteristics of cases referred to Farabi Eye Hospital with ocular superglue injuries. In a descriptive cross-sectional study conducted between December 2012 and February 2013, patients with ocular superglue injuries were evaluated. Age, sex, educational level, location, time, mechanism, type, site and time of eye injury were gathered through interview using a customized questionnaire. All participants had given consent to undergo thorough eye examination. Over the course of three months, 105 patients with ocular superglue injuries enrolled in the study, including 56(53.3%) men and 49(46.7%) women with the mean age of 24.7±11.6 (range, 2 to 53)y. The right eye, left eye and both eyes were involved in 52%, 42% and 6% of the patients, respectively. Most of injuries had occurred at home (72.4%) and at night (55%). More than half of patients (52.4%) did not take any primary aids following the ocular injury. Patient carelessness (78.1%), childhood curiosity and lack of parental supervision (11.4%), storing superglue in inappropriate places and inadvertently using superglue as eye drops due to poor vision (2.9%), inadequate awareness of superglue applications [used to stick on artificial nails (3.8%), artificial eyelashes (1.9%) and broken tooth (1%)] and being assaulted with glue (1%) were common risk factors. The frequency of ocular superglue injuries in patients referred to Farabi Eye Hospital is relatively high. This finding underlines the importance of public education and awareness about superglue injuries to the eye and taking protective measures and safety strategies in order to prevent these injures.

  17. Ocular toxicity of authentic lunar dust

    Directory of Open Access Journals (Sweden)

    Meyers Valerie E

    2012-07-01

    Full Text Available Abstract Background Dust exposure is a well-known occupational hazard for terrestrial workers and astronauts alike and will continue to be a concern as humankind pursues exploration and habitation of objects beyond Earth. Humankind’s limited exploration experience with the Apollo Program indicates that exposure to dust will be unavoidable. Therefore, NASA must assess potential toxicity and recommend appropriate mitigation measures to ensure that explorers are adequately protected. Visual acuity is critical during exploration activities and operations aboard spacecraft. Therefore, the present research was performed to ascertain the ocular toxicity of authentic lunar dust. Methods Small (mean particle diameter = 2.9 ± 1.0 μm, reactive lunar dust particles were produced by grinding bulk dust under ultrapure nitrogen conditions. Chemical reactivity and cytotoxicity testing were performed using the commercially available EpiOcularTM assay. Subsequent in vivo Draize testing utilized a larger size fraction of unground lunar dust that is more relevant to ocular exposures (particles Results In vitro testing indicated minimal irritancy potential based on the time required to reduce cell viability by 50% (ET50. Follow-up testing using the Draize standard protocol confirmed that the lunar dust was minimally irritating. Minor irritation of the upper eyelids was noted at the 1-hour observation point, but these effects resolved within 24 hours. In addition, no corneal scratching was observed using fluorescein stain. Conclusions Low-titanium mare lunar dust is minimally irritating to the eyes and is considered a nuisance dust for ocular exposure. No special precautions are recommended to protect against ocular exposures, but fully shielded goggles may be used if dust becomes a nuisance.

  18. Roles of IL-8 in ocular inflammations: a review.

    Science.gov (United States)

    Ghasemi, Hassan; Ghazanfari, Tooba; Yaraee, Roya; Faghihzadeh, Soghrat; Hassan, Zuhair Mohammad

    2011-12-01

    This review presents the current in vitro and in vivo animal and human research on the roles of IL-8 in ocular inflammatory diseases. Data sources were a literature review using Pub Med, Medline, and ISI databases (from 1990 to 2011). Search items included interleukine-8 (IL-8), CXCL8, chemokines, cytokines, alone or in combination with the, serum, aqueous, vitreous, eye, ocular, ocular tissues, ophthalmic, and review. IL-8 may be involved in primary or secondary ocular inflammations. Ocular effects of IL-8 differ based on the source of the secretion and site of the action. The most important effects of IL-8 in the eyes are angiogenic activities and induction of ocular inflammation. IL-8 plays important roles in ocular inflammation and angiogenesis in conjunctiva, cornea, iris, retina, and orbit. Anti-IL-8 targeted immunotherapy has been introduced as an important treatment modality, provided that IL-8 signal blocking takes place in desired areas and tissues.

  19. Ocular hemodynamics and glaucoma: the role of mathematical modeling.

    Science.gov (United States)

    Harris, Alon; Guidoboni, Giovanna; Arciero, Julia C; Amireskandari, Annahita; Tobe, Leslie A; Siesky, Brent A

    2013-01-01

    To discuss the role of mathematical modeling in studying ocular hemodynamics, with a focus on glaucoma. We reviewed recent literature on glaucoma, ocular blood flow, autoregulation, the optic nerve head, and the use of mathematical modeling in ocular circulation. Many studies suggest that alterations in ocular hemodynamics play a significant role in the development, progression, and incidence of glaucoma. Although there is currently a limited number of studies involving mathematical modeling of ocular blood flow, regulation, and diseases (such as glaucoma), preliminary modeling work shows the potential of mathematical models to elucidate the mechanisms that contribute most significantly to glaucoma progression. Mathematical modeling is a useful tool when used synergistically with clinical and laboratory data in the study of ocular blood flow and glaucoma. The development of models to investigate the relationship between ocular hemodynamic alterations and glaucoma progression will provide a unique and useful method for studying the pathophysiology of glaucoma.

  20. Alergia ocular: un reto diagnóstico Ocular allergy: a diagnostic challenge

    Directory of Open Access Journals (Sweden)

    Ricardo Cardona Villa

    2007-12-01

    Full Text Available El ojo es uno de los órganos más sensibles y está permanentemente expuesto a diversos agentes ambientales. Dado que la conjuntiva es un tejido inmunológicamente activo, no es sorprendente que sea un sitio común de respuestas alérgicas. Las alergias oculares son un grupo de enfermedades que afectan la superficie conjuntival y están asociadas usualmente a reacciones de hipersensibilidad tipo 1. Pueden ser divididas en varias categorías: conjuntivitis alérgica estacional, conjuntivitis alérgica perenne, queratoconjuntivitis vernal y queratoconjuntivitis atópica. La inflamación de la superficie ocular produce prurito, lagrimeo, edema conjuntival y fotofobia. Como en otras enfermedades alérgicas, se puede desarrollar una condición crónica, acompañada de remodelación de los tejidos oculares. Las estrategias para el tratamiento de la alergia ocular han aumentado exponencialmente y los clínicos disponen de un inventario cada vez mayor de agentes dirigidos a la protección del ojo contra la inflamación. En este trabajo presentamos una revisión sobre las principales formas de alergia ocular, haciendo énfasis en el cuadro clínico, el diagnóstico y las nuevas opciones terapéuticas disponibles en la actualidad. The eye, one of the most sensitive organs, is permanently exposed to different environmental agents. Since the conjunctiva is an immunologically active tissue, it is not surprising for it to be a common site for allergic responses. Ocular allergies constitute a group of diseases affecting the conjunctival surface; they are usually associated with type 1 hypersensitivity reactions. This disorder can be divided into several categories: seasonal allergic conjunctivitis, perennial allergic conjunctivitis, vernal keratoconjunctivitis and atopic keratoconjunctivitis. Ocular surface inflammation results in itching, tearing, conjunctival edema, and photophobia. As is the case with other allergic diseases, a chronic situation can also

  1. Hybrid model of the context dependent vestibulo-ocular reflex: implications for vergence-version interactions

    Science.gov (United States)

    Ranjbaran, Mina; Galiana, Henrietta L.

    2015-01-01

    The vestibulo-ocular reflex (VOR) is an involuntary eye movement evoked by head movements. It is also influenced by viewing distance. This paper presents a hybrid nonlinear bilateral model for the horizontal angular vestibulo-ocular reflex (AVOR) in the dark. The model is based on known interconnections between saccadic burst circuits in the brainstem and ocular premotor areas in the vestibular nuclei during fast and slow phase intervals of nystagmus. We implemented a viable switching strategy for the timing of nystagmus events to allow emulation of real nystagmus data. The performance of the hybrid model is evaluated with simulations, and results are consistent with experimental observations. The hybrid model replicates realistic AVOR nystagmus patterns during sinusoidal or step head rotations in the dark and during interactions with vergence, e.g., fixation distance. By simply assigning proper nonlinear neural computations at the premotor level, the model replicates all reported experimental observations. This work sheds light on potential underlying neural mechanisms driving the context dependent AVOR and explains contradictory results in the literature. Moreover, context-dependent behaviors in more complex motor systems could also rely on local nonlinear neural computations. PMID:25709578

  2. Hybrid Model of the Context Dependent Vestibulo-Ocular Reflex: Implications for Vergence-Version Interactions

    Directory of Open Access Journals (Sweden)

    Mina eRanjbaran

    2015-02-01

    Full Text Available The vestibulo-ocular reflex (VOR is an involuntary eye movement evoked by head movements. It is also influenced by viewing distance. This paper presents a hybrid nonlinear bilateral model for the horizontal angular vestibulo-ocular reflex (AVOR in the dark. The model is based on known interconnections between saccadic burst circuits in the brainstem and ocular premotor areas in the vestibular nuclei during fast and slow phase intervals of nystagmus. We implemented a viable switching strategy for the timing of nystagmus events to allow emulation of real nystagmus data. The performance of the hybrid model is evaluated with simulations, and results are consistent with experimental observations. The hybrid model replicates realistic AVOR nystagmus patterns during sinusoidal or step head rotations in the dark and during interactions with vergence, e.g. fixation distance. By simply assigning proper nonlinear neural computations at the premotor level, the model replicates all reported experimental observations. This work sheds light on potential underlying neural mechanisms driving the context dependent AVOR and explains contradictory results in the literature. Moreover, context-dependent behaviors in more complex motor systems could also rely on local nonlinear neural computations.

  3. Ocular and visual disorders in Parkinson's disease: Common but frequently overlooked.

    Science.gov (United States)

    Ekker, Merel S; Janssen, Sabine; Seppi, Klaus; Poewe, Werner; de Vries, Nienke M; Theelen, Thomas; Nonnekes, Jorik; Bloem, Bastiaan R

    2017-07-01

    Patients with Parkinson's disease (PD) often compensate for their motor deficits by guiding their movements visually. A wide range of ocular and visual disorders threatens the patients' ability to benefit optimally from visual feedback. These disorders are common in patients with PD, yet they have received little attention in both research and clinical practice, leading to unnecessary - but possibly treatable - disability. Based on a literature search covering 50 years, we review the range of ocular and visual disorders in patients with PD, and classify these according to anatomical structures of the visual pathway. We discuss six common disorders in more detail: dry eyes; diplopia; glaucoma and glaucoma-like visual problems; impaired contrast and colour vision; visuospatial and visuoperceptual impairments; and visual hallucinations. In addition, we review the effects of PD-related pharmacological and surgical treatments on visual function, and we offer practical recommendations for clinical management. Greater awareness and early recognition of ocular and visual problems in PD might enable timely instalment of tailored treatments, leading to improved patient safety, greater independence, and better quality of life. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Prognostic value of an ocular trauma score in ocular firecracker trauma.

    Science.gov (United States)

    Qi, Ying; Zhu, Yu

    2013-01-01

    The aim of this study was to report the incidence and management of ocular firecracker trauma and to assess the predictive value of an Ocular Trauma Score (OTS) in ocular firecracker trauma. The study includes consecutive case study and retrospective analysis of ocular firecracker trauma. Numerical values rendered to the OTS variables (visual acuity, rupture, endophthalmitis, perforating or penetrating injury, retinal detachment, and afferent pupillary defect) at presentation were summated and converted to OTS categories. The likelihood of the final visual acuities in each category were calculated. The sensitivity and specificity of OTS were also determined. Forty-eight patients (54 eyes) were enrolled in the study. Male patients accounted for 85.4%. Of the total patients, 62.5% were younger than 15 years. Bystanders accounted for 47.9%. The average follow up was 18.5±3.6 months. The most common clinical manifestation was ocular penetrating or perforating injury. Of the total number of patients, 53.7% had best-corrected vision, at the time of their last follow up, ranging from 20/50-20/200. The OTS has 100% sensitivity and specificity to predict nonlight perception, light perception/hand motion, and 1/200-19/200. The OTS has 45% sensitivity and 100% specificity to predict vision of 20/200-20/50. The OTS has 100% sensitivity and 65% specificity to predict vision of ≥20/40. The clinical manifestations of ocular firecracker trauma in Zhengzhou are more severe than in other countries, but similar to reports of other cities of comparable size to that in China. The OTS has good predictive value for ocular firecracker trauma with 100% sensitivity and specificity to predict a final vision of nonlight perception, light perception/hand motion, and 1/200-19/200.

  5. OCULAR DISORDERS IN CHILDREN WITH DEVELOPMENTAL DELAY

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    Meera Suresh Joshi

    2017-08-01

    Full Text Available BACKGROUND In India, an estimated 1.5-2.5% children below 2 years of age are developmentally delayed. A higher incidence of ocular disability is seen in these children, refractive errors and strabismus being most common. These can add to the overall burden of health as most of them have developmental comorbidities. The aim of the study is to study the ocular disorders in children with developmental delay. MATERIALS AND METHODS We studied 112 children between the 2-12 years of age diagnosed to have developmental delay. All the subjects underwent a detailed ophthalmic evaluation including visual acuity testing using Snellen’s charts (3m and 6m and Log MAR charts (recorded as per Snellen’s vision testing to maintain uniformity, cycloplegic refraction, torchlight and slit-lamp evaluation and dilated fundus examination. The data was tabulated and represented using bar diagrams, Pie charts and graphs. The results were expressed as percentages. Design-Cross-sectional, observational study. RESULTS 66 boys and 46 girls (total 112 were evaluated. The mean age of the study population was 7.8 years ± 2.4 SD. The aetiology of developmental delay was cerebral palsy (64%, Down syndrome (22%, autism (7%, intellectual disability (4.5% and 1 case each of congenital hypothyroidism and ataxia telangiectasia. The prevalence of ocular disorders was found to be 84.8%, which was slightly higher in girls (87% as compared to boys (83%. Refractive error (79.5% was the commonest ocular disorder followed by strabismus (46.4%. Astigmatism (44.6% was the commonest refractive error, which was divided into myopic astigmatism (19.6%, hyperopic astigmatism (13.8% and mixed astigmatism (11.2%. Simple hyperopia was seen in 21.9% subjects and simple myopia in 12.1%. Exotropia (52% was commoner than esotropia (48%. Other ocular abnormalities included optic atrophy, nystagmus, epicanthal folds, cataract, mongoloid slant, ptosis, telecanthus, conjunctival telangiectasia and

  6. Gross motor control

    Science.gov (United States)

    Gross motor control is the ability to make large, general movements (such as waving an arm or lifting a ... Gross motor control is a milestone in the development of an infant. Infants develop gross motor control before they ...

  7. Amniotic membrane transplantation for acute ocular burns.

    Science.gov (United States)

    Clare, Gerry; Suleman, Hanif; Bunce, Catey; Dua, Harminder

    2012-09-12

    Ocular surface burns can be caused by chemicals (alkalis and acids) or by direct heat. Amniotic membrane transplantation (AMT) performed in the acute phase (day 0 to day 7) of an ocular surface burn is reported to relieve pain, accelerate healing and reduce scarring and blood vessel formation. The surgery involves applying a patch of amniotic membrane (AM) over the entire ocular surface up to the eyelid margins. To assess the effects of AMT on the eyes of people having suffered acute ocular surface burns. We searched CENTRAL (which contains the Cochrane Eyes and Vision Group Trials Register) (The Cochrane Library 2012, Issue 6), MEDLINE (January 1946 to June 2012), EMBASE (January 1980 to June 2012), Latin American and Caribbean Literature on Health Sciences (LILACS) (January 1982 to June 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 11 June 2012. We included randomised trials of medical therapy and AMT applied in the first seven days after an ocular surface burn compared to medical therapy alone. Two authors independently assessed the risk of bias of included studies and extracted relevant data. We contacted trial investigators for missing information. We summarised data using risk ratios (RRs) and mean differences (MDs) as appropriate. We included one RCT of 100 participants with ocular burns that were randomised to treatment with AMT and medical therapy or medical therapy alone. A subset of patients (n = 68) who were treated within the first seven days of the injury met the inclusion criteria and were included in the analysis. The remaining 32 eyes were excluded. The included subset consisted of 36 moderate (Dua classification II-III) and 32 severe (Dua

  8. [Conjunctival microbiota in patients with ocular allergy].

    Science.gov (United States)

    Libório, Alexandre Mattoso; Nishiwaki-Dantas, Maria Cristina; Mimica, Lycia Mara Jenne; Dantas, Paulo Elias Correa; Lima, Ana Luísa Höfling de

    2005-01-01

    To evaluate de presence of conjunctival aerobic microbiota in patients with ocular allergy as compared to a control group. One hundred and thirty-three patients were evaluated from April to June 2001 and divided into 2 groups. Sixty-three patients with allergic conjunctivitis (without medication) were in group A and 70 patients from the general outpatient clinic were in group B (control group). Samples from the conjunctival sac of the right eye were collected and cultured in solid media (blood, chocolate and Sabouraud agar). In group A, 30 cultures (47.7%) were positive and 6 (8.6%) in group B. Seven bacteria were isolated from group A and 4 from group B. Statistical analysis revealed significant association between positive cultures and allergic conjunctivitis. Bacterial microbiota was more frequently found in patients with ocular allergy.

  9. OCULAR MANIFESTATIONS OF VIRAL INFECTIONS IN CHILDREN

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    E. Yu. Markovа

    2016-01-01

    Full Text Available In case of viral infections, ophthalmologists, pediatricians and general practitioners should all be aware of ocular manifestations of these diseases. According to our observations, despite the presence of corneal disorders, in 95 percent of children changes were reversible and in 1.5 months visual acuity was high. Only in five percent of cases despite the intensive therapy, patients had bacterial complications, causing a decrease in visual acuity.The combined  efforts of infectious disease specialists and ophthalmologists as well as timely and proper treatment are required to reduce the inflammation symptoms and prevent complications. By adding Ophtalmoferon® medication to the complex therapy of ocular surface diseases we observed its high therapeutic efficacy and a good safety profile. This medication is available in the form of ready-to-use eye drops, unlike other antiviral agents, improving  its compliance in outpatients.

  10. Reduction of intra-ocular pressure by ocular compression before combined peri- and retrobulbar block.

    Science.gov (United States)

    Kallio, H; Harju, M P; Ihanamäki, T; Vesti, E T; Kivelä, T

    2011-04-01

    The intra-ocular pressure immediately before glaucoma surgery can be raised. We wished to investigate if ocular compression for 20 min before a combined peri- and retrobulbar injection would result in a lower pressure after the block. Sixty consecutive patients scheduled for filtration surgery were randomly assigned to receive ocular compression using an external pressure device for 20 min before combined peri- and retrobulbar injection (intervention group, who also received compression after the block) or to a control group in whom pressure was applied only after the block was completed. The intra-ocular pressure was measured at baseline, after the 20-min pre-injection compression (intervention group), after injecting the block, and after the 10-min post-injection compression. The pressure did not differ between groups at baseline, after the block or after the post-injection compression. In the intervention group, the compression before the block reduced the median (IQR [range]) pressure from 21.0 (17.0-25.0 [12.0-40.0]) mmHg to 16.8 (12.5-22.5 [7.5-33.5]) mmHg (pintra-ocular pressure, but applying an additional compression for 20 min before injecting the block is not beneficial. © 2011 The Authors. Anaesthesia © 2011 The Association of Anaesthetists of Great Britain and Ireland.

  11. Ocular findings in Norwegian patients with ataxia-telangiectasia: a 5 year prospective cohort study.

    Science.gov (United States)

    Riise, Ruth; Ygge, Jan; Lindman, Carl; Stray-Pedersen, Asbjørg; Bek, Toke; Rødningen, Olaug Kristin; Heiberg, Arvid

    2007-08-01

    To describe the outcome of ophthalmologic examination of 10 Norwegian children with ataxia-telangiectasia (AT) followed through 5 years. Ten Norwegian patients with AT aged 2-22 years (three females, seven males) were examined. The diagnosis was confirmed clinically as well as with molecular genetic studies. Conventional ophthalmologic examination was performed and supplemented by photographs of the conjunctiva, video recordings and registration of eye motility in five consecutive years. Additionally conjunctival biopsies were performed at the end of the follow-up period. General ataxia was usually detected when the child started to walk. All children over the age of 4 years had abnormal saccade movements, a form of ocular motor apraxia. Conjunctival telangiectasias were mostly visible at 4-5 years, primarily within the palpebral fissure. Immunohistochemical examination of conjunctival biopsies showed an increased number of cross-sections of blood vessels and neurons surrounded by glial tissue. There was a tendency to slightly earlier onset of conjunctival telangiectasias in the patients homozygous for a founder mutation compared with the other patients. The diagnosis of AT can be supported at preschool age by the onset of ocular motor apraxia and conjunctival telangiectasias. The findings become more prominent with age. The conjunctival telangiectasias seem to appear slightly earlier in the patients who are homozygous for a Norwegian founder mutation than in the rest of the patients.

  12. Selenium and ocular health in New Zealand.

    Science.gov (United States)

    Sheck, Leo; Davies, Jo; Wilson, Graham

    2010-06-11

    Selenium is an essential mineral and severe selenium deficiency is known to cause significant health problems. It has been well documented that New Zealand soil is low in selenium. Recent studies have addressed the roles of selenoproteins in the eyes, with evidence suggesting that selenium supplementation may have a role in preventing cataract formation and age-related maculopathy. This paper summarises the role of selenium in ocular and general health and discusses selenium supplementation in a New Zealand specific context.

  13. [Epstein Barr and cytomegaloviruses in ocular pathology].

    Science.gov (United States)

    Magdei, Corina; Cuşnir, Valeriu; Bârcâ, Ludmila

    2010-01-01

    Epstein-Barr virus (EBV) and Citomegalovirus (CMV) are Herpesviridae family representative and presents a real danger for human. A very high infect risk of population farther the danger The ocular pathology induced by them can affect all media and tunics of optic analyzer. An etiologic differentiation is necessary for the mentioned viruses induced diseases. The etiologic differentiation has like purpose the enforcement of an effective and optimal antiviral and immunomodulating therapy.

  14. Unusual ocular presentation of acute toxoplasmosis.

    Science.gov (United States)

    Willerson, D; Aaberg, T M; Reeser, F; Meredith, T A

    1977-01-01

    Four patients with toxoplasmosis are reported with unusual presenting ocular lesions. One patient had an active lesion that appeared to involve the optic nerve as well as focal toxoplasmosis chorioretinitis at the macula. A second patient had a pale optic nerve in association with the classical chorioretinal scars of toxoplasmosis. The third patient had toxoplasmosis chorioretinitis of the macula with subretinal neovascularisation. The fourth patient had a branch artery occlusion complicating acute retinitis. Images PMID:588525

  15. Ocular ultrasound findings in optic disk melanocytoma

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    Andrés Lisker-Cervantes

    2017-11-01

    Conclusion: Melanocytomas are small, benign tumors that are highly assessable by ocular ultrasound when their elevation surpasses 0.5 mm. In our study, the internal reflectivity ranged from high to very high, unlike other malignancies such as choroidal melanoma which tend to present with low internal reflectivity. The avascularity of the tumor is a common finding. Ultrasound is a remarkable tool that helps detect benign characteristics in a pigmented optic disk tumor and helps establish a more reliable diagnosis.

  16. Vitamin D in ocular and systemic health

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    Solani D. Mathebula

    2015-03-01

    Full Text Available Accumulated data supports the argument that vitamin D possesses several biological and molecular actions apart from its role in calcium absorption and facilitation of gene expression. Vitamin D deficiency has been an associated risk factor for cardiovascular disease,metabolic syndrome and ocular complications. The aim of this review is to summarise the most relevant data regarding these associations and to try to clarify whether, and to what extent, oral vitamin D supplementation could be used as a beneficial intervention in such diseases.Vitamin D is produced in skin exposed to sunlight UVB radiation and is then metabolised by the kidney into calciferol, which is an active form. The main function of vitamin D is to promote calcium and phosphorus absorption, and studies have shown that a lack of itplays an important role in ocular conditions, such as age-related macular degeneration and diabetic retinopathy. Recent studies have suggested that vitamin D may protect the diabetic retina; however, other vitamin D-associated conditions (diabetes, hypertension and cardiovascular diseases may result in secondary ocular manifestations and the potential forsight-threatening complications. The purpose of this review is to describe the current literature on the role of vitamin D in ocular and systemic wellness. However, more research is needed to determine if increasing levels of this vitamin can assist in preventing age-related macular degeneration or diabetic retinopathy. Since vitamin D is a circulating steroid hormone, its receptors are found in almost every cell in the human body, and this suggests that vitamin D might have a very broad role for overall health. However, there is still demand for further research to clarify the clinical use of vitamin D in the prevention and treatment of various chronic diseases.

  17. Trends in serious ocular trauma in Scotland.

    Science.gov (United States)

    Desai, P; Morris, D S; Minassian, D C; MacEwen, C J

    2015-05-01

    To report trends in serious, sight-threatening ocular trauma in Scotland. A prospective, population-based, observational study of patients with ocular trauma admitted to hospital in Scotland during a 12-month period (2008-2009), conducted through the British Ophthalmic Surveillance Unit. Data on circumstances of the injuries and visual outcomes were collected using protocols standardised to those from an earlier study (1991-1992) to allow direct comparisons over time. In all, 0.3% of all emergency admissions in Scotland were for ocular trauma. Significant differences were observed between the time periods in where an injury occurred (P=0.009): a reduction of those occurring in a sports/leisure facility (8.2%) and an increase in those occurring on the street (21.4%). Assaults remained the most common cause of injury (31%). Gender differences persisted with females more likely to have an injury from falls (OR=8.67; 95% CI: 2.41-31.49; P=0.002), or in the home (OR=5.40; 95% CI: 1.69-17.16; P=0.009 ), and less likely to have one in the workplace (P=0.06). Poor visual outcome was associated with injuries occurring in the home (OR=4.33, P=0.047), in a public place (OR=6.25, P=0.047), and those caused by a fall (OR 42.75, P<0.001); or assault (OR 7.29, P=0.019). Half of those with a poor outcome have no perception of light. Serious ocular trauma remains an infrequent, sight-threatening event, associated with significant monocular visual morbidity. The findings suggest a shift from corporate to personal responsibility for risk awareness, health, and safety.

  18. Motor improvement and corticospinal modulation induced by hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy in patients with chronic stroke.

    Science.gov (United States)

    Fujiwara, Toshiyuki; Kasashima, Yuko; Honaga, Kaoru; Muraoka, Yoshihiro; Tsuji, Tetsuya; Osu, Rieko; Hase, Kimitaka; Masakado, Yoshihisa; Liu, Meigen

    2009-02-01

    We devised a therapeutic approach to facilitate the use of the hemiparetic upper extremity (UE) in daily life by combining integrated volitional control electrical stimulation with a wrist splint, called hybrid assistive neuromuscular dynamic stimulation (HANDS). Twenty patients with chronic hemiparetic stroke (median 17.5 months) had moderate to severe UE weakness. Before and immediately after completing 3 weeks of training in 40-minute sessions, 5 days per week over 3 weeks and wearing the system for 8 hours each day, clinical measures of motor impairment, spasticity, and UE functional scores, as well as neurophysiological measures including electromyography activity, reciprocal inhibition, and intracortical inhibition were assessed. A follow-up clinical assessment was performed 3 months later. UE motor function, spasticity, and functional scores improved after the intervention. Neurophysiologically, the intervention induced restoration of presynaptic and long loop inhibitory connections as well as disynaptic reciprocal inhibition. Paired pulse transcranial magnetic stimulation study indicated disinhibition of the short intracortical inhibition in the affected hemisphere. The follow-up assessment showed that improved UE functions were maintained at 3 months. The combination of hand splint and volitional and electrically induced muscle contraction can induce corticospinal plasticity and may offer a promising option for the management of the paretic UE in patients with stroke. A larger sample size with randomized controls is needed to demonstrate effectiveness.

  19. Management of severe ocular burns with symblepharon.

    Science.gov (United States)

    Shi, Weiyun; Wang, Ting; Gao, Hua; Xie, Lixin

    2009-01-01

    To evaluate the effect of lamellar keratoplasty combined with limbal stem cells, using amniotic membrane, autologous conjunctiva, and pseudopterygium to reconstruct external eyes for severe ocular burns with symblepharon. Thirty eyes of 29 patients had severe symblephara resulting from eye burns. According to the range of the symblepharon and the loss of limbal stem cells, partial lamellar keratoplasty combined with partial limbal stem cell treatment was performed in 19 eyes, and total lamellar keratoplasty with total limbus was performed in 11 eyes. All patients had amniotic membrane and autologous conjunctival transplantation, and the pseudopterygium was preserved to reconstruct the fornix. Symblephara were completely relieved in 19 eyes. They remained partially in ten eyes in strip-like form, but seven of these were completely relieved after further autologous conjunctival transplantation. One eye was treated with tarsorrhaphy for eyelid malformation. The remaining pseudopterygium became thinner after the operation and showed no symblepharon. Immune rejection occurred in eight corneal grafts; clarity was restored in four of these, while there was graft neovascularization in the remaining four. Depending on the area of symblepharon and the loss of limbal stem cells, partial or total lamellar keratoplasty combined with limbal stem cells, using amniotic membrane, autologous conjunctiva and pseudopterygium to reconstruct external eyes appears to be effective in treating severe ocular burns with symblepharon. Pseudopterygium can partly substitute autologous conjunctiva in ocular surface reconstruction.

  20. Platelet rich plasma in ocular surface.

    Science.gov (United States)

    Riestra, A C; Alonso-Herreros, J M; Merayo-Lloves, J

    2016-10-01

    The use of platelet-rich preparations has experienced a significant increase in recent years due to its role in tissue-repair and regeneration. The aim of this study is to examine the available evidence regarding the application of plasma rich in growth factors, and its variations, on the ocular surface. A review is also presented on the effects of platelet-derived growth factors, the implications of the preparation methods, and the existing literature on the safety and efficacy of these therapies in ocular surface diseases. Despite the widespread use of platelet preparations there is no consensus on the most appropriate preparation method, and growth factors concentration vary with different systems. These preparations have been used in the treatment of ocular surface diseases, such as dry eye or persistent epithelial defects, among others, with good safety and efficacy profiles, but further studies are needed to compare to the currently available alternatives. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  1. Experimental models of autoimmune inflammatory ocular diseases

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    Fabio Gasparin

    2012-04-01

    Full Text Available Ocular inflammation is one of the leading causes of blindness and loss of vision. Human uveitis is a complex and heterogeneous group of diseases characterized by inflammation of intraocular tissues. The eye may be the only organ involved, or uveitis may be part of a systemic disease. A significant number of cases are of unknown etiology and are labeled idiopathic. Animal models have been developed to the study of the physiopathogenesis of autoimmune uveitis due to the difficulty in obtaining human eye inflamed tissues for experiments. Most of those models are induced by injection of specific photoreceptors proteins (e.g., S-antigen, interphotoreceptor retinoid-binding protein, rhodopsin, recoverin, phosducin. Non-retinal antigens, including melanin-associated proteins and myelin basic protein, are also good inducers of uveitis in animals. Understanding the basic mechanisms and pathogenesis of autoimmune ocular diseases are essential for the development of new treatment approaches and therapeutic agents. The present review describes the main experimental models of autoimmune ocular inflammatory diseases.

  2. Miastenia grave y miastenia grave ocular

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    Rosa María Naranjo Fernández

    Full Text Available La miastenia grave es una enfermedad caracterizada por debilidad y fatiga de los músculos voluntarios debido a una trasmisión anómala a nivel de la unión neuromuscular. La prevalencia es aproximadamente de 5 casos/100 000 personas. La miastenia grave puede ser bulbar, ocular o generalizada.Existen formas clínicas en la infancia como son la miastenia neonatal transitoria, la miastenia congénita y la miastenia juvenil. Los músculos oculares, faciales y bulbares son los más frecuentes afectados por la enfermedad. Cuando los síntomas se limitan a la musculatura cercana al ojo se denomina miastenia grave ocular. Una vez el oftalmólogo diagnostica o sospecha la miastenia grave, un neurólogo generalmente dirige la comprobación y tratamiento. El papel del oftalmólogo continúa siendo importante, además de chequear la motilidad y disfunción palpebral y proporcionar el alivio sintomático para estos desórdenes, debe estar alerta a la posibilidad de ambliopía.

  3. Oculomotricidade e seus fundamentos Ocular motility: foundations

    Directory of Open Access Journals (Sweden)

    Harley E. A. Bicas

    2003-10-01

    Full Text Available Partindo-se de um circuito esquemático relacionando os sistemas sensorial (visual binocular e oculomotor, cujos defeitos em vias aferentes ou eferentes, ou de suas interações, explicam o aparecimento dos estrabismos e suas conseqüências, são examinados os fundamentos e referenciais da movimentação ocular. Apresentam-se os conceitos de eixos e planos, centro de massa e de rotação, definem-se os movimentos monoculares de translação e de rotação e os binoculares de versões e vergências. É também referida a função dos centros de comando para movimentos voluntários e reflexos, a dos núcleos oculomotores e a respectiva inervação aos músculos oculares externos. Numa segunda parte (fisiologia da musculatura ocular extrínseca são comentadas as atividades de contração e relaxamento e a importância da lei de Sherrington. Voltando-se ao conceito de posição primária do olhar e dos referenciais das rotações, menciona-se a diversidade de vários sistemas de medidas. Em seguida, são analisadas as ações musculares rotacionais com bases no plano de ação muscular e na distribuição anatômica dos músculos, levando a resultados em posição primária do olhar e nas outras. Os efeitos de fáscias e membranas intermusculares são também comentados, terminando-se com a concepção moderna sobre as ações musculares (ação simultânea de todos os músculos em quaisquer das posições oculares. Com os condicionantes da lei de Hering, desenvolve-se o conceito de posições diagnósticas (das disfunções oculomotoras, diferentemente do clássico: os músculos são considerados em pares, de acordo às suas ações predominantes ___ horizontais (retos horizontais, verticais (retos verticais ou torcionais (oblíquos. Em cada qual devem ser comparadas as ações em condições diametralmente opostas de fixação ocular e posições do olhar (por exemplo, supradextroversão na fixação com o olho direito e infralevoversão na fixa

  4. Ocular dominance and visual function testing.

    Science.gov (United States)

    Lopes-Ferreira, D; Neves, H; Queiros, A; Faria-Ribeiro, M; Peixoto-de-Matos, S C; González-Méijome, J M

    2013-01-01

    To show the distribution of ocular dominance as measured with sensory and eye sighting methods and its potential relationship with high and low contrast LogMAR visual acuity in presbyopic subjects. Forty-four presbyopes (48.5 ± 3.5 years) participated in this study. Ocular dominance was determined by eye sighting (hole-in-card) and sensorial (+1.50 D lens induced blur) methods. According to the dominance detected with each method (RE: right eye or LE: left eye), patients were classified in dominance type 1 (RE/RE), type 2 (RE/LE), type 3 (LE/RE) and type 4 (LE/LE). Baseline refractive error (MSE) was RE:-0.36 ± 1.67 D and LE:-0.35 ± 1.85 D (P = 0.930). RE was the dominant eye in 61.4% and 70.5% of times as obtained from sensorial and sighting methods, respectively. Most frequent dominance was of type 1 (52.3%), in this case the RE showed statistically significant better distance low contrast LogMAR VA (0.04 LogMAR units) compared to the LE (P eye sighting and sensorial methods to define ocular dominance agreed in more than half of cases. Amount of MSE was not significantly different between dominant and non-dominant eye. But in case of right dominance, the RE presented better distance low contrast VA compared to the LE.

  5. A uniform format for ocular imaging devices.

    Science.gov (United States)

    Ishikawa, H; Liebmann, J M; Uji, Y; Ritch, R

    1999-01-01

    To develop a uniform file format of ocular imaging data, including, but not limited to, ultrasound biomicroscopy, optical coherence tomography, and nerve fiber analyzer, capable of being transmitted via Internet or intranet for collaborative research and telemedicine use. File filters were developed as dynamic link libraries (DLLs). These can read the original raw data format of each ocular imaging device. A data file format was also designed to describe these raw data uniformly in three different types of compression: noncompressed, run length compression, and differential pulse code modulation (DPCM). These three file formats were then tested in the following aspects: file size, speed of reading, and speed of writing. Run length compression failed to compress raw data, while DPCM compressed raw data successfully (< or =35.5%). The speed of reading and writing files was slowest in DPCM. However, the actual time of reading and writing was fast enough (<0.6 s) for daily work regardless of file compression methods. The format designed has robust potential to be the standard file format for transmission of any ocular imaging raw data.

  6. PAEDIATRIC OCULAR TRAUMA IN KUCHING, SARAWAK, MALAYSIA

    Directory of Open Access Journals (Sweden)

    INTAN G

    2011-01-01

    Full Text Available Purpose: To evaluate the demography, aetiology, type and outcome of paediatric ocular trauma in tertiary centre in Malaysia. Method: We retrospectively studied 118 eyes from 117 patients over a period of 36 months (January 2006 to December 2008. All ocular injuries in patients aged 12 and below seen in the Ophthalmology Department for the first time were included in thisstudy. Results: Mean age of patients was 6.1±3.0 years. 68 cases (58.2% occurred in pre-school children, whereas 49 (41.9% in school-aged children. Boys accounted for 65.8% of cases. There was no predilection for either right or the left eye. 47% of cases (56 patients occurred in Malay. Most of the injuries took place at home when the children were alone (p<0.05. Sharp objects were the commonest cause (45 cases, 38.1%. The majority of cases (103, 87.3% were considered preventable. The frequency of open and closed globe injury was similar. Hyphema was more common in closed globe injury compared to open globe injury (p<0.05. Other associated injuries such as cataract, vitreous hemorrhage and retinal hemorrhage are similar between the two groups. Visual outcome is generally poor with only 34 eyes (28.8% had no visual impairment. Conclusion: Ocular trauma in children is an important cause of visual loss. Most cases occurred at home and were preventable. Prevention through education is the best approach.

  7. Ocular pathology in congenital heart disease.

    Science.gov (United States)

    Mansour, A M; Bitar, F F; Traboulsi, E I; Kassak, K M; Obeid, M Y; Megarbane, A; Salti, H I

    2005-01-01

    To describe the ocular findings in subjects with congenital heart disease (CHD). In a prospective study, the same observer examined 240 consecutive patients with CHD admitted to the medical centre. Two independent geneticists performed identification of syndromes. The commonest anatomic cardiac anomalies were ventricular or atrial septal defects (62), tetralogy of Fallot (39), pulmonary stenosis (25), and transposition of the great arteries (24). The heart lesions were divided physiologically into volume overload (90), cyanotic (87), and obstructive (63). In all, 105 syndromic subjects included the velocardiofacial syndrome (18), Down's syndrome (17), CHARGE association (6), DiGeorge syndrome (5), Williams syndrome (3), Edwards syndrome (3), Noonan syndrome (3), VACTERL association (2), and Patau syndrome (trisomy 13) (2). The paediatric team recognized 51 patients as syndromic. Two independent geneticists recognized additional 54 patients as syndromic. Positive eye findings were present in 55% (132) and included retinal vascular tortuosity (46), optic disc hypoplasia (30), trichomegaly (15), congenital ptosis (12), strabismus (11), retinal haemorrhages (8), prominent eyes (7), and congenital cataract (6). There was a strong correlation between the retinal vascular tortuosity and both a low haematocrit (P=0.000) and a low arterial oxygen saturation (P=0.002). Patients with CHD are at a high risk for ocular pathology and need screening for various ocular abnormalities.

  8. Ocular tissue engineering: current and future directions.

    Science.gov (United States)

    Karamichos, D

    2015-02-17

    Tissue engineering (TE) is a concept that was first emerged in the early 1990s to provide solutions to severe injured tissues and/or organs [1]. The dream was to be able to restore and replace the damaged tissue with an engineered version which would ultimately help overcome problems such as donor shortages, graft rejections, and inflammatory responses following transplantation. While an incredible amount of progress has been made, suggesting that TE concept is viable, we are still not able to overcome major obstacles. In TE, there are two main strategies that researchers have adopted: (1) cell-based, where cells are been manipulated to create their own environment before transplanted to the host, and (2) scaffold-based, where an extracellular matrix is created to mimic in vivo structures. TE approaches for ocular tissues are available and have indeed come a long way, over the last decades; however more clinically relevant ocular tissue substitutes are needed. Figure 1 highlights the importance of TE in ocular applications and indicates the avenues available based on each tissue.[...].

  9. Motor control for a brushless DC motor

    Science.gov (United States)

    Peterson, William J. (Inventor); Faulkner, Dennis T. (Inventor)

    1985-01-01

    This invention relates to a motor control system for a brushless DC motor having an inverter responsively coupled to the motor control system and in power transmitting relationship to the motor. The motor control system includes a motor rotor speed detecting unit that provides a pulsed waveform signal proportional to rotor speed. This pulsed waveform signal is delivered to the inverter to thereby cause an inverter fundamental current waveform output to the motor to be switched at a rate proportional to said rotor speed. In addition, the fundamental current waveform is also pulse width modulated at a rate proportional to the rotor speed. A fundamental current waveform phase advance circuit is controllingly coupled to the inverter. The phase advance circuit is coupled to receive the pulsed waveform signal from the motor rotor speed detecting unit and phase advance the pulsed waveform signal as a predetermined function of motor speed to thereby cause the fundamental current waveform to be advanced and thereby compensate for fundamental current waveform lag due to motor winding reactance which allows the motor to operate at higher speeds than the motor is rated while providing optimal torque and therefore increased efficiency.

  10. Study of ocular aberrations with age.

    Science.gov (United States)

    Athaide, Helaine Vinche Zampar; Campos, Mauro; Costa, Charles

    2009-01-01

    Aging has various effects on visual system. Vision deteriorate, contrast sensitivity decreases and ocular aberrations apparently make the optical quality worse across the years. To prospective evaluate ocular aberrations along the ages. Three hundred and fifteen patients were examined, 155 were male (39.36%) and 160 were female (60.63%). Ages ranged from 5 to 64 year-old, the study was performed from February to November, 2004. Patients were divided into 4 age-groups according to IBGE (Instituto Brasileiro de Geografia e Estatística) classification: 68 patients from 5 to 14 year-old, 55 patients from 15 to 24 year-old, 116 from 25 to 44 year-old and 76 from 45 to 67 year-old. All patients had the following characteristics: best corrected visual acuity > 20/25, emmetropia or spherical equivalent < 3.50 SD, refractive astigmatism < 1.75 CD on cycloplegic refraction, normal ophthalmologic exam and no previous ocular surgeries. This protocol was approved by Federal University of São Paulo Institutional Review Board. Total optical aberrations were measured by H-S sensor LadarWave Custom Cornea Wavefront System (Alcon Laboratories Inc, Orlando, FLA, USA) and were statistically analysed. Corneal aberrations were calculated using CT-View software Version 6.89 (Sarver and Associates, Celebration, FL, USA). Lens aberrations were calculated by subtraction. High-order (0.32 e 0.48 microm) and ocular spherical aberrations (0.02 e 0.26 microm) increased respectively in child and middle age groups. High order (0.27 microm) and corneal spherical aberrations (0.05 microm) did not show changes with age. Lens showed a statistically significant spherical aberration increase (from -0.02 to 0.22 microm). Vertical (from 0.10 to -0.07 microm) and horizontal coma (from 0.01 to -0.12 microm) presented progressively negative values with aging. High-order and spherical aberrations increased with age due to lens contribution. The cornea did not affect significantly changes observed on ocular

  11. Ocular trauma resulting from paintball injury.

    Science.gov (United States)

    Pahk, Patricia J; Adelman, Ron A

    2009-04-01

    Paintball-related ocular injuries result in severe damage and loss of vision. Despite efforts to increase public awareness and improve safety features, the incidence of eye injuries has increased over time. We examined the characteristics and ocular effects of paintball injury at our tertiary referral center. Retrospective review of charts of patients with paintball injury between 1998-2005. Fourteen patients were evaluated for paintball injury; 13 (93%) were male and one (7%) was female. Average age was 17 years (range from 9 to 30). Thirteen patients (95%) did not wear eye protection; one is unknown. Injuries occurred while playing paintball in three patients (21%); ten (71%) were injured in either accidental (four patients) or intentional (six patients) shootings not associated with play. Minimum follow-up was 6 weeks, except for one patient who was lost to follow-up. Seven patients (50%) had final visual acuity (VA) better than 20/200, six patients (43%) were 20/200 or worse, and information on one patient was not available. VA, except in one case, improved with treatment. Decreased VA in this case was due to proliferative vitreoretinopathy (PVR). Hyphema was noted in ten patients (71%), vitreous hemorrhage in eight (57%), retinal hemorrhage in six (43%), retinal tear or detachment in six (43%), commotio retinae in six (43%), iris injury in five (36%), keratopathy in four (29%), lens injury in two (14%), subluxation of lens in two (14%), secondary glaucoma in two (14%), open globe/intraocular foreign body (IOFB) in one (7%), choroidal rupture in one (7%), and proliferative vitreoretinopathy (PVR) in one (7%). Ten patients (71%) required intervention (surgery, laser retinopexy or cryotherapy). Paintball trauma results in significant ocular injury and loss of vision. Most injuries occur in unsupervised settings without proper eye protection. Ten patients (71%) were injured in accidental or intentional shootings. Lack of supervision and use of paintball materials

  12. Dry Eye Management: Targeting the Ocular Surface Microenvironment

    Science.gov (United States)

    Zhang, Xiaobo; Jeyalatha M, Vimalin; Qu, Yangluowa; He, Xin; Ou, Shangkun; Bu, Jinghua; Jia, Changkai; Wang, Junqi; Wu, Han; Liu, Zuguo

    2017-01-01

    Dry eye can damage the ocular surface and result in mild corneal epithelial defect to blinding corneal pannus formation and squamous metaplasia. Significant progress in the treatment of dry eye has been made in the last two decades; progressing from lubricating and hydrating the ocular surface with artificial tear to stimulating tear secretion; anti-inflammation and immune regulation. With the increase in knowledge regarding the pathophysiology of dry eye, we propose in this review the concept of ocular surface microenvironment. Various components of the microenvironment contribute to the homeostasis of ocular surface. Compromise in one or more components can result in homeostasis disruption of ocular surface leading to dry eye disease. Complete evaluation of the microenvironment component changes in dry eye patients will not only lead to appropriate diagnosis, but also guide in timely and effective clinical management. Successful treatment of dry eye should be aimed to restore the homeostasis of the ocular surface microenvironment. PMID:28661456

  13. Roles of IL-10 in ocular inflammations: a review.

    Science.gov (United States)

    Ghasemi, Hassan; Ghazanfari, Tooba; Yaraee, Roya; Owlia, Parviz; Hassan, Zuhair Mohammad; Faghihzadeh, Soghrat

    2012-12-01

    This review represents the current in vitro, in vivo, animal and human investigations on the roles of IL-10 in ocular inflammatory conditions. The data sources were literature reviews, including Pub Med, Medline, and ISI databases (since 1989 to mid-2012). Search items were, IL-10, chemokines, cytokines, alone or in combination with, serum, aqueous, vitreous eye, ocular, ocular tissues, ophthalmic, and review. Ocular effects of IL-10 depend on the sources of the secretion and sites of the action. IL-10 plays important anti-inflammatory and especially anti-angiogenic activities in ocular tissues such as the conjunctiva, cornea, retina, choroid, and orbit. IL-10 plays major anti-inflammatory and anti-angiogenic roles in most of the ocular inflammations. Also, IL-10 plays a role in development of anterior chamber-associated immune deviation (ACAID). Any manipulation of IL-10 for treatment purposes should be considered very cautiously due to its potential hazards to the immune system.

  14. Ocular rosacea: a review Rosácea ocular: revisão

    Directory of Open Access Journals (Sweden)

    Ana Carolina Cabreira Vieira

    2012-10-01

    Full Text Available Rosacea is a prevalent chronic cutaneous disorder with variable presentation and severity. Although considered a skin disease, rosacea may evolve the eyes in 58-72% of the patients, causing eyelid and ocular surface inflammation. About one third of the patients develop potentially sight-threatening corneal involvement. Untreated rosacea may cause varying degrees of ocular morbidity. The importance of early diagnosis and adequate treatment cannot be overemphasized. There is not yet a diagnostic test for rosacea. The diagnosis of ocular rosacea relies on observation of clinical features, which can be challenging in up to 90% of patients in whom accompanying roseatic skin changes may be subtle or inexistent. In this review, we describe the pathophysiologic mechanisms proposed in the literature, clinical features, diagnosis and management of ocular rosacea, as well as discuss the need for a diagnostic test for the disease.A rosácea é uma condição cutânea crônica, que possui apresentações clínicas variáveis. Apesar de considerada uma doença dermatológica, os olhos podem ser acometidos em 58-72% dos casos, causando inflamação palpebral e da superfície ocular. Aproximadamente um terço dos pacientes desenvolve acometimento corneano, podendo causar baixa visual significativa. Diagnóstico precoce e tratamento adequado são de extrema importância, devido à significativa morbidade ocular que a doença pode causar. Não há, até o momento, um teste diagnóstico para rosácea. O diagnóstico da rosácea ocular depende da observação das manifestações clínicas, o que pode ser bastante desafiador em até 90% dos pacientes, em que os achados cutâneos são discretos ou inexistentes. Nesta revisão, descrevemos os mecanismos fisiopatológicos propostos na literatura, manifestações clínicas, diagnóstico e tratamento da rosácea ocular, assim como abordamos a necessidade de um teste diagnóstico.

  15. Ocular burns in eye traumatology emphatically on chemical burns

    OpenAIRE

    Farský, Lukáš

    2008-01-01

    Burns to the sclera, conjunctiva, cornea, and eyelid are considered ocular burns. Ocular burn injuries are classified by etiologic agents as either chemical injuries (ie, acid, alkali) or radiant energy injuries (ie, thermal, ultraviolet). Chemical injuries to the eye represent one of the true ophthalmic emergencies. While almost any chemical can cause ocular irritation, serious damage generally results from either strongly basic (alkaline) compounds or acidic compounds. Alkali injuries are m...

  16. Paintball related ocular injuries: First case report in Saudi patients

    OpenAIRE

    Al-Amry, Mohammad; Al-Ghadeer, Huda

    2017-01-01

    Paintball is a popular recreational sport. This case series describes three Saudi patients exposed to paintball ocular injuries with sever ocular trauma. Two patients developed hyphema and traumatic cataract and one patient had vitreous hemorrhage, choroidal detachment, commotio retinae and retinal tear. All patients require surgical intervention. Final best corrected visual acuity was 20/200, 20/30 and 20/50 respectively. Paintball related ocular injuries can result in severe visual loss and...

  17. High efficiency motors; Motores de alta eficiencia

    Energy Technology Data Exchange (ETDEWEB)

    Uranga Favela, Ivan Jaime [Energia Controlada de Mexico, S. A. de C. V., Mexico, D. F. (Mexico)

    1992-12-31

    This paper is a technical-financial study of the high efficiency and super-premium motors. As it is widely known, more than 60% of the electrical energy generated in the country is used for the operation of motors, in industry as well as in commerce. Therefore the importance that the motors have in the efficient energy use. [Espanol] El presente trabajo es un estudio tecnico-financiero de los motores de alta eficiencia y los motores super premium. Como es ampliamente conocido, mas del 60% de la energia electrica generada en el pais, es utilizada para accionar motores, dentro de la industria y el comercio. De alli la importancia que los motores tienen en el uso eficiente de la energia.

  18. Two different motor systems are needed to generate human speech.

    Science.gov (United States)

    Holstege, Gert; Subramanian, Hari H

    2016-06-01

    Vocalizations such as mews and cries in cats or crying and laughter in humans are examples of expression of emotions. These vocalizations are generated by the emotional motor system, in which the mesencephalic periaqueductal gray (PAG) plays a central role, as demonstrated by the fact that lesions in the PAG lead to complete mutism in cats, monkeys, as well as in humans. The PAG receives strong projections from higher limbic regions and from the anterior cingulate, insula, and orbitofrontal cortical areas. In turn, the PAG has strong access to the caudal medullary nucleus retroambiguus (NRA). The NRA is the only cell group that has direct access to the motoneurons involved in vocalization, i.e., the motoneuronal cell groups innervating soft palate, pharynx, and larynx as well as diaphragm, intercostal, abdominal, and pelvic floor muscles. Together they determine the intraabdominal, intrathoracic, and subglottic pressure, control of which is necessary for generating vocalization. Only humans can speak, because, via the lateral component of the volitional or somatic motor system, they are able to modulate vocalization into words and sentences. For this modulation they use their motor cortex, which, via its corticobulbar fibers, has direct access to the motoneurons innervating the muscles of face, mouth, tongue, larynx, and pharynx. In conclusion, humans generate speech by activating two motor systems. They generate vocalization by activating the prefrontal-PAG-NRA-motoneuronal pathway, and, at the same time, they modulate this vocalization into words and sentences by activating the corticobulbar fibers to the face, mouth, tongue, larynx, and pharynx motoneurons. © 2015 Wiley Periodicals, Inc.

  19. Ocular surface inflammation impairs structure and function of meibomian gland.

    Science.gov (United States)

    Mizoguchi, Shin; Iwanishi, Hiroki; Arita, Reiko; Shirai, Kumi; Sumioka, Takayoshi; Kokado, Masahide; Jester, James V; Saika, Shizuya

    2017-10-01

    Dysfunction of the meibomian glands alters secreted meibum quantitatively and qualitatively that can lead to damage to the ocular surface epithelium. In response to an unstable tear film cause by meibomian gland dysfunction, ocular surface epithelium is damaged and expresses inflammatory cytokines leading to secondary ocular inflammation. In turn, inflammatory disorders of the palpebral conjunctiva and lid margin may affect the structure and function of meibomian gland. The disorders include allergic conjunctivitis, long-term usage of contact lenses, dermatological diseases that affect conjunctival homeostasis, Stevens-Johnson's syndrome or chemical burning of the ocular surface and lid margin. Copyright © 2017. Published by Elsevier Ltd.

  20. Ocular shell structures in some Cretaceous trachyleberid Ostracoda

    Science.gov (United States)

    Kontrovitz, M.; Puckett, T.M.

    1998-01-01

    This is the first study of internal ocular shell structures of Cretaceous ostracodes. Internal molds from eight species of four genera from Santonian, Campanian, and Maastrichtian strata revealed a stalked ocular sinus constricted along its length and distally inflated. The latter part has anterior and posterior lobes and a subcentral concavity. These Cretaceous trachyleberids have ocular shell structures similar to Cenozoic taxa and it is presumed they functioned similarly. However, each taxon has a diagnostic ocular sinus and an inner surface of the eye tubercle that distinguishes each from all other forms examined.

  1. Association between Exposure to Smartphones and Ocular Health in Adolescents.

    Science.gov (United States)

    Kim, Joowon; Hwang, Yunji; Kang, Seungheon; Kim, Minhye; Kim, Tae-Shin; Kim, Jay; Seo, Jeongmin; Ahn, Hyojeong; Yoon, Sungjoon; Yun, Jun Pil; Lee, Yae Lim; Ham, Hyunsoo; Yu, Hyeong Gon; Park, Sue K

    2016-08-01

    Smartphone use has dramatically increased in recent years. Smartphones may have adverse health effects, particularly on the eyes, because users stare at the screen for a much longer time than they do with ordinary mobile phones. The objective of this study was to elucidate the relationship between smartphone use and ocular symptoms among adolescents. Information on smartphone use and ocular symptoms (blurring, redness, visual disturbance, secretion, inflammation, lacrimation and dryness) related to eye fatigue and strain from 715 adolescent subjects from three cities in Korea was obtained using a structured questionnaire. Ocular health was scored using number of ocular symptoms. Odds ratios (ORs), 95% confidence intervals (95% CIs) and p-values for ocular symptoms were calculated with binomial and multinomial logistic regression models. Higher prevalence rates for ocular symptoms were observed in groups with greater exposure to smartphones (p smartphone use was associated with a higher likelihood of having multiple ocular symptoms (5-7 symptoms out of 7 symptoms; p = 0.005). Excessive/intermittent use (>2 hours daily and ≤2 hours continuously) and excessive/persistent use (>2 hours daily and >2 hours continuously) compared to shorter use (smartphones was associated with a higher likelihood of having multiple ocular symptoms (OR 3.05, 95% CI 1.51-6.19; p = 0.001). Increasing exposure to smartphones can have a negative impact on ocular health in adolescents.

  2. Ocular cicatricial pemphigoid masquerading as chronic conjunctivitis: a case report

    Directory of Open Access Journals (Sweden)

    DaCosta J

    2012-12-01

    Full Text Available Joanna DaCostaMoorfields Eye Hospital, London, UKAbstract: Conjunctivitis is often considered an innocuous condition which is self-limiting. This report describes misdiagnosis of ocular cicatricial pemphigoid as chronic conjunctivitis. Ocular cicatricial pemphigoid is a rare autoimmune condition. The clinical features which are useful to distinguish this condition from infective conjunctivitis are discussed. The investigation and treatment of ocular cicatricial pemphigoid is discussed. It is important to recognize nonocular symptoms and signs that may indicate the presence of a more serious underlying pathological condition necessitating specialized ophthalmic referral and subsequent investigation and treatment.Keywords: autoimmune, conjunctivitis, ocular cicatricial pemphigoid

  3. Evidence against mobile pulleys on the rectus muscles and inferior oblique muscle: central nervous system controls ocular kinematics.

    Science.gov (United States)

    Jampel, Robert S; Shi, Dian X

    2006-01-01

    To provide evidence against the existence of orbital pulleys. Interpretation of magnetic resonance imaging (MRI) scans; video eye tracking; ocular motor nerve stimulations; and clinical observations. No pulleys or planes splitting the extraocular muscles into layers were noted on MRI scans. Smooth muscle does not antagonize striate muscle. There is no physiological evidence that human rectus pulleys shift the ocular rotational axes to attain commutative behavior. In the monkey and humans, the axes of rotation are not determined by eye position. Operations on the extraocular muscles reveal no pulleys. The somatosensory system of the central nervous system controls the extraocular muscles. The autonomic nervous and the hormonal systems control the infrastructure of the orbit vital for the function of the extraocular muscles. The three systems are integrated and controlled by the central nervous system. Neural circuits are necessary to compensate for extraocular muscle abnormalities. There are no pulleys.

  4. Profound retinal ischaemia after ranibizumab administration in an eye with ocular ischaemic syndrome

    DEFF Research Database (Denmark)

    Kofoed, Peter Kristian; Munch, Inger Christine; Larsen, Michael

    2009-01-01

    Abstract. Purpose: To report the result of ranibizumab administration in an eye with ocular ischaemic syndrome. Methods: Fluorescein angiography, ocular pneumoplethysmography and retinal vessel calibre measurement. Results: An 85-year-old man with ocular ischaemic syndrome demonstrated vision los...

  5. The impact of combined oral contraceptives on ocular tissues: a review of ocular effects

    Directory of Open Access Journals (Sweden)

    Marilita M. Moschos

    2017-10-01

    Full Text Available The aim of this manuscript is to review the action and adverse effects of combined oral contraceptives (COCs on ocular tissues. The percentage of unwanted pregnancies and the subsequent abortions make contraception crucial worldwide. Over 100 million women around the world use common contraceptive methods, including intrauterine devices, combined estrogen and progestin oral contraceptives, as well as progestin only preparations (oral contraceptives, implants or injections. COCs are widely used for contraception, but they are also indicated in menorrhagia, endometriosis, acne and hirsutism, fibroid uterus and premenstrual syndrome. However, they have been associated with high rates of cardiovascular events, venous thromboembolic disease, ischemic strokes and breast cancer. The incidence of COCs-related ocular complications is estimated to be 1 in 230 000, including dry eye symptoms, corneal edema, lens opacities and retinal neuro-ophthalmologic or vascular complications. We may infer that the serious ocular complications of COCs can be prevented by eliminating the estrogen dosage and choosing third-generation progestins. In any case, doctors should take into consideration the systemic and ocular history of the patients before selecting any method of contraception.

  6. Rehabilitación en pacientes con trauma ocular Rehabilitation of ocular trauma patients

    Directory of Open Access Journals (Sweden)

    Eduardo Ariel Ramos Gómez

    2012-01-01

    Full Text Available La rehabilitación en oftalmología tiene como función fundamental lograr el máximo aprovechamiento posible del resto visual. El traumatismo ocular es considerado una de las entidades nosológicas frecuentes que conllevan a una rehabilitación visual. Las causas que provocan este tipo de trauma son variadas y dentro de estas, las agresiones con intención de provocar daños con secuelas son muy frecuentes. Es objetivo de esta revisión puntualizar la importancia de la rehabilitación en pacientes con traumatismo ocular e incentivar el buen accionar de todos los oftalmólogos en cuanto a su atención.The main goal of rehabilitation in ophthalmology is to use as much as possible the residual vision. Ocular trauma is considered one of the common diseases that imply visual rehabilitation. The causes of eye injuries are varied; among them assaults with intent to cause damage are the most common. The objective of this article was to point out the importance of rehabilitation in patients with ocular trauma and to encourage all the ophthalmologists to act accordingly.

  7. Glaucoma in patients with ocular chemical burns.

    Science.gov (United States)

    Lin, Michelle P; Ekşioğlu, Ümit; Mudumbai, Raghu C; Slabaugh, Mark A; Chen, Philip P

    2012-09-01

    To examine the development and management of glaucoma in patients with ocular chemical burns. Retrospective, observational case series. setting: University of Washington Eye Clinics. patient population: Twenty-nine eyes (18 patients) with ocular chemical burns seen between 1997 and 2010 with a minimum of 3 months of follow-up. observation procedure: Eyes were graded using the Roper-Hall scale. main outcome measures: Long-term use of glaucoma medications (3 months or more) and need for glaucoma surgery. The mean age was 45 ± 17 years, with a mean follow-up of 75 ± 47 months (median, 66 months). Roper-Hall grade III or IV eyes (n = 20) had significantly higher intraocular pressure at presentation (35.9 vs 16.4 mm Hg; P = .001) and over follow-up were more likely to require long-term glaucoma medications (P = .003) or to undergo glaucoma surgery (P = .016) than Roper-Hall grade I or II eyes. Thirteen eyes (12 Roper-Hall grade III or IV) underwent glaucoma surgery. Eight eyes underwent glaucoma tube implant surgery; 4 required at least 1 revision. Seven eyes underwent diode laser cyclophotocoagulation; 4 required repeat treatment. Most (89%) eyes had controlled intraocular pressure at the last follow-up. However, 76% of eyes with visual acuity of 20/200 or worse at initial evaluation did not have improved vision at the last follow-up. Eyes with Roper-Hall grade III or IV ocular chemical burns were more likely to have glaucoma and to require surgery for it. Outcomes of glaucoma management generally were good, although tube implant surgeries often had complications requiring revision. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Parstatin Suppresses Ocular Neovascularization and Inflammation

    Science.gov (United States)

    Huang, Hu; Vasilakis, Panagiotis; Zhong, Xiufeng; Shen, Ji-Kui; Geronatsiou, Katerina; Papadaki, Helen; Maragoudakis, Michael E.; Gartaganis, Sotirios P.; Vinores, Stanley A.

    2010-01-01

    Purpose. Parstatin is a 41-mer peptide formed by proteolytic cleavage on activation of the PAR1 receptor. The authors recently showed that parstatin is a potent inhibitor of angiogenesis. The purpose of the present study was to evaluate the therapeutic effect of parstatin on ocular neovascularization. Methods. Choroidal neovascularization was generated in mice using laser-induced rupture of Bruch's membrane and was assessed after 14 days after perfusion of FITC-dextran. Oxygen-induced retinal neovascularization was established in neonatal mice by exposing them to 75% O2 at postnatal day (P)7 for 5 days and then placing them in room air for 5 days. Evaluation was performed on P17 after staining with anti-mouse PECAM-1. The effect of parstatin was tested after intravitreal administration. The effects of subconjunctival-injected parstatin on corneal neovascularization and inflammation in rats were assessed 7 days after chemical burn-induced corneal neovascularization. Retinal leukostasis in mice was assessed after perfusion with FITC-conjugated concanavalin A. Results. Parstatin potently inhibited choroidal neovascularization with an IC50 of approximately 3 μg and a maximum inhibition of 59% at 10 μg. Parstatin suppressed retinal neovascularization with maximum inhibition of 60% at 3 μg. Ten-microgram and 30-μg doses appeared to be toxic to the neonatal retina. Subconjunctival parstatin inhibited corneal neovascularization, with 200 μg the most effective dose (59% inhibition). In addition, parstatin significantly inhibited corneal inflammation and VEGF-induced retinal leukostasis. In all models tested, scrambled parstatin was without any significant effect. Conclusions. Parstatin is a potent antiangiogenic agent of ocular neovascularization and may have clinical potential in the treatment of angiogenesis-related ocular disorders. PMID:20538980

  9. Ocular Dominance and Visual Function Testing

    Directory of Open Access Journals (Sweden)

    D. Lopes-Ferreira

    2013-01-01

    Full Text Available Purpose. To show the distribution of ocular dominance as measured with sensory and eye sighting methods and its potential relationship with high and low contrast LogMAR visual acuity in presbyopic subjects. Method. Forty-four presbyopes (48.5 ± 3.5 years participated in this study. Ocular dominance was determined by eye sighting (hole-in-card and sensorial (+1.50 D lens induced blur methods. According to the dominance detected with each method (RE: right eye or LE: left eye, patients were classified in dominance type 1 (RE/RE, type 2 (RE/LE, type 3 (LE/RE and type 4 (LE/LE. Results. Baseline refractive error (MSE was RE:−0.36 ± 1.67 D and LE:−0.35 ± 1.85 D (P=0.930. RE was the dominant eye in 61.4% and 70.5% of times as obtained from sensorial and sighting methods, respectively. Most frequent dominance was of type 1 (52.3%, in this case the RE showed statistically significant better distance low contrast LogMAR VA (0.04 LogMAR units compared to the LE (P<0.05. Conclusions. The dominance was more frequent in RE in this sample. The eye sighting and sensorial methods to define ocular dominance agreed in more than half of cases. Amount of MSE was not significantly different between dominant and non-dominant eye. But in case of right dominance, the RE presented better distance low contrast VA compared to the LE.

  10. Ocular Munchausen syndrome resulting in bilateral blindness.

    Science.gov (United States)

    Salvo, M; Pinna, A; Milia, P; Carta, F

    2006-01-01

    Münchausen syndrome is a factitious disorder in which patients knowingly harm themselves for subconscious psychological reasons in order to be hospitalized. Recognition of this psychopathology is important, to prevent potentially severe eye damage. Ocular Münchausen syndrome is uncommon. The authors describe an elderly woman with recurrent, probably self-induced, ocular trauma leading to bilateral blindness. The authors are unaware of any previously reported cases of Münchausen syndrome resulting in bilateral blindness and occurring in old age. A 73-year-old woman was first seen in 1991 with a closed-globe injury to the right eye, apparently following a household fall. Physical examination showed no sign of extraocular trauma. Right visual acuity was 20/30 after 2 months. She was readmitted in May 2003 with left globe rupture, allegedly following a domestic fall. No extraocular trauma was found. She developed ocular phthisis 6 months postoperatively. The patient was admitted again in February 2004 with right globe rupture, following another alleged domestic fall. Physical examination showed no sign of extraocular trauma. Right visual acuity was 20/400 2 months postoperatively. Psychiatric evaluation revealed Münchausen syndrome. Psychotherapy was prescribed, but refused by her family. Diagnosis of Münchausen syndrome is difficult to make in the ophthalmic department. Münchausen patients have little or no ability to control their self-destructive behavior. A sympathetic and supportive approach is therefore required and these patients should be urgently referred to a psychiatrist with experience in factitious disorders. Even with psychotherapy, which is often refused, the prognosis remains poor.

  11. Buccal Epithelium in treating Ocular Surface Disorders

    Directory of Open Access Journals (Sweden)

    Srinivas KR

    2008-11-01

    Full Text Available Background - Ocular surface disorders due to limbal stem cell deficiency are an important cause of ocular morbidity and visual loss. Although autologous limbal stem cell transplants have helped in the management of unilateral disease, allografts in those with bilateral disease often fail due to immunological reasons. The use of autologous buccal epithelium cultivated on amniotic membrane has been described as a useful approach in the management of this condition. It is the purpose of this study to explore the feasibility of using a novel thermo-gelatin polymer (TGP as a substrate to culture these cells, and to characterize them using RNA extraction and RT-PCR. Methods - Oral cheek mucosal biopsies were obtained from 5 adult patients undergoing Modified Osteo-Odonto Keratoprosthesis surgery. The specimens were transported to the laboratory in transport medium. The cells were released using enzymatic digestion and seeded in both convention culture medium and TGP. The resulting cellular growth was characterized using RNA extraction and RT-PCR. Results - Cells could be cultured from 4 of the 5 specimens. In one specimen, contamination occurred and this was discarded. In the other specimens, the cheek epithelial cells could be cultured in both the conventional culture medium and TGP, with equal ease. RT-PCR revealed the presence of K3, a marker for epithelial cells, and GAPDH indicating the presence of some adipose tissue as well. Conclusions - It is possible to culture autologous cheek mucosal epithelial cells using TGP, a synthetic scaffold, without the need for other biological substrates. Since the specimens are obtained from the oral cavity, stringent asepsis is required. Further studies are required for histopathological characterization of the cultured cells and to create a model for delivery onto the ocular surface of eyes with bilateral surface disease due to limbal stem cell deficiency.

  12. Ocular safety of Viagra, (sildenafil citrate).

    Science.gov (United States)

    Laties, A M; Fraunfelder, F T

    1999-01-01

    To date, sildenafil citrate (Viagra) gives every evidence of being a safe drug for the eye despite a series of expressed concerns. A review of how its ocular safety profile has been identified offers insights into the strengths and weaknesses of present systems and resources for judging the ocular safety of Viagra or, for that matter, of any new drug. Such insights include: The great value of careful, informed assessment of preclinical information gleaned from laboratory experiments. By and large, such assessments point the way toward appropriate clinical evaluation. For Viagra, early in its development it was noted that besides exerting a major inhibitory effect on the intended target, the vascular-associated enzyme phosphodiesterase 5 (PDE5), the drug also exerts a lesser but definite inhibitory effect on the closely related PDE6, located in the retina. For this reason, preclinical evaluation of the drug included electroretinography plus postmortem histology. In addition, an extended eye examination was incorporated into clinical protocols. The often chaotic but invaluable information stream that becomes available once marketing approval has been gained and large populations begin to use a drug. False alarms, misattribution, and erroneous information are the order of the day. Nevertheless, as information accumulates, patterns of response clarify and the true nature of special susceptibility for subpopulations, if any, becomes apparent. A role for the astute clinician remains: Subtle changes or unusual risks for subpopulations can be missed entirely for long periods of time. A manifest need for improvement in evaluation of postmarketing side-effects. This need has led to the establishment of a new discipline: pharmacoepidemiology. In ophthalmology, the National Registry of Drug Induced Ocular Side-Effects maintains a constant and invaluable surveillance. Examples are supplied to illustrate each of these major points: Our presentation will include data gleaned from

  13. Serological IgG avidity test for ocular toxoplasmosis

    Directory of Open Access Journals (Sweden)

    Suresh S

    2012-01-01

    Full Text Available Subramaniam Suresh1, Saidin Nor-Masniwati1, Muhd Nor Nor-Idahriani1, Wan-Hitam Wan-Hazabbah1, Mohamed Zeehaida2, Embong Zunaina11Department of Ophthalmology, 2Department of Medical Microbiology and Parasitology, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, MalaysiaBackground: The purpose of this study was to evaluate the immunoglobulin (Ig G avidity of serological toxoplasmosis testing in patients with ocular inflammation and to determine the clinical manifestations of ocular toxoplasmosis.Methods: A retrospective review of all patients presenting with ocular inflammation to the Hospital Universiti Sains Malaysia, Kelantan, Malaysia between 2005 and 2009 was undertaken. Visual acuity, clinical manifestations at presentation, toxoplasmosis antibody testing, and treatment records were analyzed.Results: A total of 130 patients with ocular inflammation were reviewed retrospectively. The patients had a mean age of 38.41 (standard deviation 19.24, range 6–83 years. Seventy-one patients (54.6% were found to be seropositive, of whom five (3.8% were both IgG and IgM positive (suggestive of recently acquired ocular toxoplasmosis while one (0.8% showed IgG avidity ≤40% (suggestive of recently acquired ocular toxoplasmosis and 65 patients (50.0% showed IgG avidity >40% (suggestive of reactivation of toxoplasmosis infection. Chorioretinal scarring as an ocular manifestation was significantly more common in patients with seropositive toxoplasmosis (P = 0.036. Eighteen patients (13.8% were diagnosed as having recent and/or active ocular toxoplasmosis based on clinical manifestations and serological testing.Conclusion: Ocular toxoplasmosis is a clinical diagnosis, but specific toxoplasmosis antibody testing helps to support the diagnosis and to differentiate between reactivation of infection and recently acquired ocular toxoplasmosis.Keywords: ocular toxoplasmosis, chorioretinal scar, toxoplasmosis antibody, IgG avidity test

  14. The prevalence of ocular surface complaints in Brazilian patients with glaucoma or ocular hypertension

    Directory of Open Access Journals (Sweden)

    Vital Paulino Costa

    2013-08-01

    Full Text Available PURPOSE: To examine the prevalence of ocular surface complaints in Brazilian patients with glaucoma or ocular hypertension who used topical intraocular pressure (IOP-lowering regimens. METHODS: In this multicenter, noninterventional, single-visit study, adults with glaucoma or ocular hypertension treated with an IOP-lowering regimen were administered the 12-item ocular surface disease index (OSDI questionnaire. Each response was scored on a 5-point scale, with 0 indicating symptom present none of the time and 4 indicating symptom present all of the time. The average of the 12 item responses for each patient was transformed to a scale from 0 to 100, with higher scores representing worse disabilities. OSDI results then were categorized as absence of OSD (scores of 0-12, mild OSD (scores of 13-22, moderate OSD (scores of 23-32, or severe OSD (scores of 33100. RESULTS: The 173 enrolled patients had a mean age of 61.2 years, were women in 65.3% of cases, and had glaucoma in 89.0% of cases and ocular hypertension in 11.0% of cases. OSDI scores for 158 patients using 1 IOP-lowering therapy indicated no OSD in 37.3% of patients (59/158, mild OSD in 20.9% (33/158, moderate OSD in 17.1% (27/158, and severe OSD in 24.7% (39/158. For the 120 patients using 1 IOP-lowering medication and having a known duration of diagnosis of glaucoma or ocular hypertension, mean OSDI scores were numerically higher (worse for the 39 patients with a diagnosis ≥6 years long (score 25 [± 20], indicating moderate OSD than for the 81 patients with a diagnosis lasting <6 years (score 22 [± 20], indicating mild OSD; however, no significant differences in OSDI scores by duration of diagnosis were evident in means (P=0.49, distributions (P≥0.26, or correlation (P=0.77. CONCLUSIONS: A large proportion of Brazilian patients treated with 1 IOP-lowering therapy had some ocular surface complaints.

  15. Ocular cells and light: harmony or conflict?

    Science.gov (United States)

    Jurja, Sanda; Hîncu, Mihaela; Dobrescu, Mihaela Amelia; Golu, Andreea Elena; Bălăşoiu, Andrei Theodor; Coman, Mălina

    2014-01-01

    Vision is based on the sensitivity of the eye to visible rays of the solar spectrum, which allows the recording and transfer of visual information by photoelectric reaction. Any electromagnetic radiation, if sufficiently intense, may cause damages in living tissues. In a changing environment, the aim of this paper is to point out the impact of light radiation on ocular cells, with its phototoxicity potential on eye tissues. In fact, faced with light and oxygen, the eye behaves like an ephemeral aggregate of unstable molecules, like a temporary crystallization threatened with entropia.

  16. Cine magnetic resonance imaging of ocular motility.

    Science.gov (United States)

    Cadera, W; Viirre, E; Karlik, S

    1992-01-01

    We describe a technique of generation of a cine motion picture of ocular movements in a patient with Duane Type II exotropia. With the magnetic resonance scanning unit, multiple scans can be sequenced to give a graphic animation to the eyes as targets are fixated across the visual field. With this technique, we were able to clearly view the contractility of the extraocular muscles and note the changes in pulling directions of the muscles in this patient. The restriction of movement due to the cocontraction of the horizontal rectus muscles was readily apparent.

  17. Penetrating ocular trauma from trampoline spring.

    Science.gov (United States)

    Spokes, David; Siddiqui, Salina; Vize, Colin

    2010-02-01

    The case is presented of a 12-year old boy who sustained severe penetrating ocular trauma while playing on a domestic trampoline. A main spring broke under tension and the hook had struck the eye at high velocity and penetrated the sclera. Primary repair was undertaken but on review it became apparent the eye could not be salvaged. Evisceration was carried out and an orbital implant was placed. Post-operative cosmesis is acceptable. This type of injury has not been reported before. Adult supervision of children on trampolines is recommended to minimise the chance of serious injury.

  18. Microbiota conjuntival em pacientes com alergia ocular

    OpenAIRE

    Alexandre Mattoso Libório; Maria Cristina Nishiwaki-Dantas; Lycia Mara Jenne Mimica; Paulo Elias Correa Dantas; Ana Luísa Höfling de Lima

    2005-01-01

    OBJETIVO: Avaliar a presença de microbiota aeróbia da conjuntiva de portadores de alergia ocular e comparar a um grupo controle. MÉTODOS: Foram examinados 133 pacientes no período de abril a junho de 2001 divididos em 2 grupos. O grupo A foi composto de 63 portadores de conjuntivite alérgica (sem uso de medicação) e o grupo B de 70 pacientes do ambulatório geral (controle). Foram coletadas amostras do fundo de saco conjuntival do olho direito de todos os pacientes e o material foi semeado em ...

  19. Ocular aberrations in barn owl eyes.

    Science.gov (United States)

    Harmening, Wolf M; Vobig, Michael A; Walter, Peter; Wagner, Hermann

    2007-10-01

    Optical quality in barn owl eyes is presented in terms of measuring the ocular wavefront aberrations with a standard Tscherning-type wavefront aberrometer under natural viewing conditions. While accommodative state was uncontrolled, all eyes were focused within 0.4D with respect to the plane of the aberrometer. Total RMS wavefront error was between 0.06 and 0.15 microm (mean: 0.10 microm, STD: 0.03 microm, defocus cancelled) for a 6 mm pupil. The results suggest that image quality in barn owl eyes is excellent.

  20. [The ocular manifestations in systemic lupus erythematosus].

    Science.gov (United States)

    Gheorghiu, M

    1996-01-01

    Retinal involvement in systemic lupus erythematosus is dominated by a microangiopathy of unknown aetiology, with occlusive consequences. Although cases of severe retinal ischaemia have been recently described, from a statistic point of view, the occlusive phenomena seem to have declined over the last decades, under the influence of a better therapy and follow-up of the disease. The relatively high incidence of papilloedema and the fact that this oedema might be unilateral or asymptomatic are pointed out. The importance of ophthalmic examination in patients with SLE-like syndromes or in seronegative cases of SLE is revealed. Other ocular manifestation of the disease are reviewed.

  1. Fabrication of a custom ocular prosthesis.

    Science.gov (United States)

    Sethi, Tania; Kheur, Mohit; Haylock, Colin; Harianawala, Husain

    2014-01-01

    Defects of the eye may follow removal of a part of or the entire orbit. This results in the patient becoming visually, esthetically and psychologically handicapped. Restoring the defect with a silicone- or acrylic-based prosthesis not only restores esthetics but also gives back the lost confidence to the patient. This is a case report of a patient with a 'pthisical eye' and details the steps in fabrication of an ocular prosthesis. Particular attention has been given to the laboratory process in this technique to minimize the residual monomer content in the artificial eye.

  2. Irritation of ocular tissue by irreversible hydrocolloids.

    Science.gov (United States)

    Moergeli, J R; Fraleigh, E M; Ostrowski, J S; Pelleu, G B

    1985-08-01

    Two ophthalmic and two dental irreversible hydrocolloid materials were tested on rabbit conjunctivae to determine histologically their potential to irritate these tissues. Each of the four impression materials elicited nearly the same amount of inflammatory response. The differences between the response of the controls and the response to Ophthalmic Mold-Eye, Jelset Special Formula, and Kerr Alignate Type II were significant. These results indicate that certain dental irreversible hydrocolloids may be used for ocular prostheses but that they should be used with caution because of the inflammation caused by irreversible hydrocolloids.

  3. Involvement of Nrf2 in Ocular Diseases

    Directory of Open Access Journals (Sweden)

    Shehzad Batliwala

    2017-01-01

    Full Text Available The human body harbors within it an intricate and delicate balance between oxidants and antioxidants. Any disruption in this checks-and-balances system can lead to harmful consequences in various organs and tissues, such as the eye. This review focuses on the effects of oxidative stress and the role of a particular antioxidant system—the Keap1-Nrf2-ARE pathway—on ocular diseases, specifically age-related macular degeneration, cataracts, diabetic retinopathy, and glaucoma. Together, they are the major causes of blindness in the world.

  4. Circumstance and outcome of ocular paintball injuries.

    Science.gov (United States)

    Greven, Craig M; Bashinsky, Alice L

    2006-02-01

    To determine the circumstance and outcome of ocular injuries attributable to paintball projectiles. Retrospective interventional case series. Institutional review board approved retrospective chart review of 19 consecutive eyes with paintball injuries with minimum follow-up of 3 months. Ten eyes (53%) had final visual acuity of 20/40 or better, while seven (36%) were 20/200 or worse. Ten eyes were injured in paintball games, (two formal and eight informal), while nine (47%) were injured by accidents or assaults not associated with any "game." Paintball injuries often cause severe and permanent visual loss. Nearly half of these injuries occur outside a war game setting as accidents or assaults.

  5. Blunt Ocular Trauma Associated with Paintball Gun

    Directory of Open Access Journals (Sweden)

    Yavuz Özpınar

    2013-04-01

    Full Text Available A 21-year-old male patient presented to our hospital with a blunt paintball trauma to his left eye. The patient had corneal edema, traumatic cataract, traumatic mydriasis, and secondary glaucoma in his left eye. After corneal edema resolved, cataract surgery was performed. Because of uncontrolled intraocular pressure despite antiglaucoma medications, an Ahmed glaucoma valve was implanted. In the postoperative period, the patient’s visual acuity was 1/10. Paintball-related ocular injuries can be severe and visually devastating. (Turk J Ophthalmol 2013; 43: 135-7

  6. Curvature sensor for ocular wavefront measurement.

    Science.gov (United States)

    Díaz-Doutón, Fernando; Pujol, Jaume; Arjona, Montserrat; Luque, Sergio O

    2006-08-01

    We describe a new wavefront sensor for ocular aberration determination, based on the curvature sensing principle, which adapts the classical system used in astronomy for the living eye's measurements. The actual experimental setup is presented and designed following a process guided by computer simulations to adjust the design parameters for optimal performance. We present results for artificial and real young eyes, compared with the Hartmann-Shack estimations. Both methods show a similar performance for these cases. This system will allow for the measurement of higher order aberrations than the currently used wavefront sensors in situations in which they are supposed to be significant, such as postsurgery eyes.

  7. Ocular response analyser measurements and central corneal thickness in ocular rosacea patients.

    Science.gov (United States)

    Palamar, Melis; Degirmenci, Cumali; Ertam, Ilgen; Yagci, Ayse

    2017-02-01

    Rosacea is a chronic cutaneous disorder which is known to cause inflammation and increased proteolytic activity on the ocular surface that might lead to corneal biomechanical alterations. The aim of this study is to evaluate the corneal biomechanical properties of ocular rosacea patients and compare the measurements with healthy individuals as measured with Reichert ocular response analyser (ORA). Besides full eye examination [best corrected visual acuity (BCVA), intraocular pressure (IOP) measured with Goldmann applanation tonometry (IOP-G)], central corneal thickness (CCT), and ORA [corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated IOP (IOPcc), Goldmann correlated IOP (IOPg)] measurements of 30 eyes of 15 ocular rosacea patients (study group) and 30 eyes of 15 healthy individuals (control group) were performed. For comparisons paired t test was used. Mean age of study group was 45.26 ± 11.65 (range 25 and 63) and control group was 45.00 ± 8.91 (range 26 and 58) years (p = 0.865). No significant difference in BCVA, CCT, IOP-G, IOPcc was detected among groups. However, IOPg, CH, and CRF in the study group were significantly lower than in the control group (p = 0.013, p = 0.013, p = 0.009, respectively). IOPg, CH, and CRF parameters of ocular rosacea patients were significantly lower than normal individuals. These differences and their probable clinical reflections that might effect making decisions in conditions such as glaucoma should be investigated in larger number of patients.

  8. Clinical application of ocular trauma score for mechanical ocular injury in armed forces

    Directory of Open Access Journals (Sweden)

    Ying ZHANG

    2011-10-01

    Full Text Available Objective To evaluate the predictive value of ocular trauma score(OTS in mechanical ocular injuries occurring in military forces,and compare the difference of OTS application between ocular injury caused by military training and non-military training.Methods The data of 633 inpatients from armed forces suffering from injury of 665 eyes were retrospectively reviewed.Of the 665 injured eyes,326 were injured during military training and 339 during non-military training.The likelihood of final visual acuity(VA calculated with the OTS score was compared with that by the present OTS study,and the correlation between the score and final VA was then analyzed.Results Compared with the distribution of final VA in standard OTS score,the ratio in category 1 was statistically different in present study(P 0.05.There were significant differences in ratio of category 3 between eyes injured by military and non-military training(P < 0.05,and both ratios in category 1 were significantly different compared with those in standard OTS(P < 0.01,e.g.the ratio of NLP was lower(50% vs 73%,P < 0.01;43% vs 73%,P < 0.01;and the ratio in category 2 was significantly different between the eyes injured by non-military training and standard OTS(P < 0.05.However,the OTS showed positive correlation with final VA in present study(P < 0.0001.Conclusion OTS calculated at initial examination may primarily provide a piece of prognostic information of mechanical ocular injuries,and is of special benefit for deciding a prompt management or for evacuation decision for severe ocular injuries caused by military training.

  9. Visual Impairment and Ocular Findings among Deaf and Hearing ...

    African Journals Online (AJOL)

    Visual Impairment and Ocular Findings among Deaf and Hearing Impaired School Children in Central Region, Ghana. ... The overall prevalence of visual impairment was 5.8% among hearing impaired school children in the Central Region of Ghana. ... Keywords: Disability, eye, ear, refractive error, ocular deviation .

  10. Ocular Injuries: Another Example of the Heavy Prize of Terrorism ...

    African Journals Online (AJOL)

    Injuries to the face and ocular structures could occur at the war front not only to the enemies, but also to unsuspecting friends of the security agents. We report here a case of ocular injury involving an air force personnel (lance corporal) who was mistakenly hit on the face by the back blast of a rocket‑propelled grenade shot ...

  11. Astute and safe use of topical ocular corticosteroids in general ...

    African Journals Online (AJOL)

    Corticosteroids are an effective treatment for ocular inflammation, but they must be used with caution. Corticosteroids are the most effective way to treat ocular inflammation. They relieve symptoms rapidly and often prevent permanent damage. These medications, however, must be used with caution, as use of ...

  12. bilateral orbito-ocular gunshot injury in a nigerian male

    African Journals Online (AJOL)

    Orbito-ocular injuries with retained intra-orbital foreign bodies affecting both orbits are uncommon in civilian practice. This case report aims to highlight an unusual presentation of bilateral orbito-ocular injury with retained intra-orbital foreign bodies following accidental explosion of a locally fabricated dane gun.

  13. Post Operative pain following Ocular Surgery: Relevant Preventitive ...

    African Journals Online (AJOL)

    Objective: To determine the optimal time and mode of administration of postoperative analgesics following ocular surgery. Background: Most elective ocular surgery are said to be accompanied by onlymild pain. This knowledge, however, is not available to the prospective patientand this usually results in undue fear of eye ...

  14. A retrospective study of ocular neoplasms in Benin City, Nigeria ...

    African Journals Online (AJOL)

    Ocular neoplasm is one of the least investigated ocular disorders in Nigeria. Although relatively rare, they play a role in causing blindness and even death in adults and children. In this study, the records of all patients/seen at the eye clinic and specimen received at the histopathology department of the University of Benin, ...

  15. Ocular problems among public service retirees in a Southern ...

    African Journals Online (AJOL)

    Materials and Methods: Participants were retired public servants who consented to ocular examinations at their pension pay points in Port Harcourt during the 2012 World Sight Day. Visual acuity, ocular examinations including fundoscopy and intraocular pressure measurements were recorded and subsequently analyzed ...

  16. Ocular Problems Among Public Service Retirees in a Southern ...

    African Journals Online (AJOL)

    to ocular examinations at their pension pay points in Port Harcourt during the 2012 World Sight Day. Visual acuity, ocular examinations including fundoscopy and intraocular pressure measurements were recorded and subsequently analyzed using. Statistical Package for Social Sciences version 20. Results: Five hundred ...

  17. Pattern of ocular morbidity among children seen in a Nigerian ...

    African Journals Online (AJOL)

    This is because a delay in treatment for some causes of childhood blindness can lead to amblyopia. Furthermore, the number of “blind years” resulting from ... Refractive error (19.5%) was the most common ocular morbidity seen, followed by ocular trauma (13.1%), allergic conjunctivitis (11.1%) and cataract (10.9%).

  18. Pattern of Ocular Pathologies Diagnosed with B-scan ...

    African Journals Online (AJOL)

    biometry for calculation of optical power of artificial lens implants is another advantage of ocular .... Loss of vision. 8. 8. Photopsia. 3. 3. Bangal, et al.: Pattern of ocular pathologies diagnosed with B-scan ultrasonography. Nigerian Journal of Ophthalmology ¦ Jul-Dec 2016 ¦ Volume 24 ¦ Issue 2. 73. [Downloaded free from ...

  19. Epidemiology, Pathophysiology, and the Future of Ocular Toxoplasmosis

    NARCIS (Netherlands)

    Kijlstra, A.; Pedersen, E.

    2014-01-01

    Despite large advances in the field of ocular toxoplasmosis, large gaps still exist in our knowledge concerning the epidemiology and pathophysiology of this potentially blinding infectious disease. Although ocular toxoplasmosis is considered to have a high health burden, still little is known about

  20. Long term ocular and neurological involvement in severe congenital toxoplasmosis

    NARCIS (Netherlands)

    Meenken, C.; Assies, J.; van Nieuwenhuizen, O.; Holwerda-van der Maat, W. G.; van Schooneveld, M. J.; Delleman, W. J.; Kinds, G.; Rothova, A.

    1995-01-01

    This study was set up to determine the long term ocular and systemic sequelae in patients with severe congenital toxoplasmosis. Cross sectional and retrospective study of 17 patients with severe congenital toxoplasmosis. In addition to chorioretinitis (100%), the most common abnormal ocular features

  1. Implementing and applying the Ocular Trauma Score: the challenges

    Directory of Open Access Journals (Sweden)

    Desirée C Murray

    2016-01-01

    Full Text Available Ocular trauma is a significant cause of unilateral blindness in the Caribbean in both adults and children. In Trinidad and Tobago, blunt ocular injury will typically account for around a third of all referrals from the Accident and Emergency department to the ophthalmology unit.

  2. Utilization of ocular safety devices among Sawmill workers in Nigeria

    African Journals Online (AJOL)

    Ocular examination was done on site with a pen torch, portable hand-held slit lamp bio-microscope and direct ophthalmoscope. ... Conclusion: There is need to safeguard the ocular health of sawmill workers in Nigeria by provision of eye safety devices, health education of the workers on the benefits of its use and ...

  3. Clinical Evaluation of Ocular Antiviral Effect of Garcinia Kolanut ...

    African Journals Online (AJOL)

    Clinical Evaluation of Ocular Antiviral Effect of Garcinia Kolanut Water Extract in Epidemic Haemorrhagic Keratoconjunctivitis in Lagos. ... Critical awareness and preventive measures are usually applied. These infections are ... They all used only the sterile Garcinia kolanut water extract as drops for their ocular complaints.

  4. Ocular changes in pregnant Nigerian women | Ebeigbe | Nigerian ...

    African Journals Online (AJOL)

    Objective: Pregnancy results in a lot of hormonal changes in the body and the eyes are no exception. These ocular changes could be physiologic, pathologic or a modification of a pre-existing condition. The aim of this study was to determine physiologic ocular changes that are associated with pregnancy in healthy Nigerian ...

  5. Ocular Hazards in Ophthalmic Dispensing Industry in South East ...

    African Journals Online (AJOL)

    The prevalence of ocular hazards in ophthalmic dispensing industry in south east Nigeria was carried out using 70 subjects drawn from different towns in the region. Tables were used to analyze the data obtained from his study. Results showed that ocular hazards are involved in ophthalmic dispensing depending on the ...

  6. uptake of ocular surgeries at ebonyi state university teaching hospi

    African Journals Online (AJOL)

    Dr Chijioke Onyeknowu

    Conclusion: The yearly surgical uptake at EBSUTH was low and cataract extraction was the most common ocular surgery performed. Key words: ocular surgeries, analysis, EBSUTH, Abakaliki. INTRODUCTION. The eye clinic of Ebonyi State University Teaching Hospital. (EBSUTH), Abakaliki was revitalized and equipped ...

  7. Hutchinson's sign as a marker of ocular involvement in HIVpositive ...

    African Journals Online (AJOL)

    Background. A positive Hutchinsonfs sign indicates an increased risk of ocular involvement in herpes zoster ophthalmicus (HZO). We examined the sensitivity of Hutchinsonfs sign as an indicator of ocular involvement in a consecutive series of patients presenting with HZO. Methods. We conducted a descriptive ...

  8. Epidemiological Survey of Paediatric Ocular Morbidity in North ...

    African Journals Online (AJOL)

    Vernal disease was the commonest ocular morbidity seen constituting 349 cases (40.3%), ocular trauma 152 (17.6%), infective conjunctivitis 106 (12.3%) and refractive errors 89 (10.2%). The location of industries (rice mills, sawmills, cement factory) away from residential areas, availability of antiallergic drugs must be ...

  9. uptake of ocular surgeries at ebonyi state university teaching hospi

    African Journals Online (AJOL)

    Dr Chijioke Onyeknowu

    SUMMARY. Objective: To ascertain the number, types and frequencies of ocular surgeries done at Ebonyi State University Teaching. Hospital (EBSUTH), Abakaliki, with a view to improving the overall surgical uptake. Methods: A retrospective review of ocular surgeries done at. EBSUTH between January 2003 and April ...

  10. Orbito-Ocular Tumours In Nigerian Children | Onwasigwe ...

    African Journals Online (AJOL)

    Conclusion: This study has brought to light the many aspect of orbito-ocular tumours in Nigerian children and also highlighted the many problems caused by inadequate facilities for diagnosis and management. Key words: Orbito-ocular tumours, children, retinoblastoma, tumour sites. [Jnl College of Medicine Vol.7(2) 2002: ...

  11. Ocular morbidity pattern in Abonnema, Akuku–Toru local ...

    African Journals Online (AJOL)

    Background: Ocular morbidity patterns are indicative of the ocular health status of communities. They are significant pointers to the prevalent and emerging eye diseases in any country. The absence of professional eye care services in most Nigerian villages has necessitated the use of eye camps offering free ...

  12. Ocular Uveitis as the Initial Presentation of Syphilis

    Directory of Open Access Journals (Sweden)

    May-Ching Hong

    2007-07-01

    Conclusion: Syphilis can be presented initially as ocular uveitis without obvious systemic manifestation. Ophthalmologists play an important role in the early diagnosis and treatment of syphilis. If treated early enough, the response is good, even if the patient is allergic to penicillin. Awareness of the multiple manifestations of ocular syphilis is the key to early detection of the disease.

  13. Immunopathology in ocular toxoplasmosis: facts and clues

    Directory of Open Access Journals (Sweden)

    Justus G Garweg

    2009-03-01

    Full Text Available Although parasite-mediated host cell lysis is deemed to be an important cause of tissue destruction in ocular toxoplasmosis (OT, the severity of the disease is probably correlated with hypersensitivity and inflammation. Notwithstanding, the mechanisms that regulate the inflammatory process in recurrent OT are poorly understood. Recent evidence has identified interleukin (IL 17 as a marker for disease severity. The ocular and cerebral presence of this cytokine is generally associated with the induction of autoimmune responses in the brain and the eye. Indeed, there are indications that autoimmunity may contribute to clinical variability in the activity of OT. IL-23, which induces the proliferation of IL-17-producing cells and IL-27, which is a counterplayer to IL-17, may regulate T(H-1-cell-mediated responses in OT. The importance of these cytokines in experimental models of uveitis and encephalitis has been recently reported. CD25(+ regulatory T-cells may control the local inflammatory response and protect the host against collateral inflammatory tissue damage. The responses of these cells to OT may be suitably tailored to cope with either an acquired or a congenital aetiology. Knowledge relating to immunoreactivity in OT has grown impressively during the past few years. Its characteristic and variable features have been identified and the potential relevance of autoimmunity has been assessed. In light of this knowledge, potential future treatment options have been considered.

  14. Describing ocular aberrations with wavefront vergence maps.

    Science.gov (United States)

    Nam, Jayoung; Thibos, Larry N; Iskander, D Robert

    2009-05-01

    A common optometric problem is to specify the eye's ocular aberrations in terms of Zernike coefficients and to reduce that specification to a prescription for the optimum sphero-cylindrical correcting lens. The typical approach is first to reconstruct wavefront phase errors from measurements of wavefront slopes obtained by a wavefront aberrometer. This paper applies a new method to this clinical problem that does not require wavefront reconstruction. Instead, we base our analysis of axial wavefront vergence as inferred directly from wavefront slopes. The result is a wavefront vergence map that is similar to the axial power maps in corneal topography and hence has a potential to be favoured by clinicians. We use our new set of orthogonal Zernike slope polynomials to systematically analyse details of the vergence map analogous to Zernike analysis of wavefront maps. The result is a vector of slope coefficients that describe fundamental aberration components. Three different methods for reducing slope coefficients to a spherocylindrical prescription in power vector forms are compared and contrasted. When the original wavefront contains only second order aberrations, the vergence map is a function of meridian only and the power vectors from all three methods are identical. The differences in the methods begin to appear as we include higher order aberrations, in which case the wavefront vergence map is more complicated. Finally, we discuss the advantages and limitations of vergence map representation of ocular aberrations.

  15. Effects of chalazion excision on ocular aberrations.

    Science.gov (United States)

    Sabermoghaddam, Ali A; Zarei-Ghanavati, Siamak; Abrishami, Mojtaba

    2013-06-01

    The goal of this study was to compare higher-order aberrations before and after upper lid chalazion excision. Fourteen eyes from 12 patients (8 females, mean age: 28.7 ± 2.7 years) with upper lid chalazion were enrolled in this prospective interventional case series. Chalazia were excised by standard transconjunctival vertical incision. Ocular aberrations were evaluated by aberrometry (ZyWave) before and 2 months after chalazion excision. Root mean square of total higher-order aberrations decreased from 0.67 ± 0.12 to 0.43 ± 0.15 μm (P = 0.012) after excision. The root mean square of Zernike orders in the vertical and horizontal trefoil and horizontal coma were decreased after excision. Orbscan IIz tomography showed a statistically significant decrease in 5 mm zone irregularity (P = 0.027) and an increase in minimum simulated keratometry after surgery (P = 0.046). Chalazion increases higher-order aberrations, as measured by the Hartmann-Shack aberrometer, which could affect the preoperative evaluation and results of refractive surgery, especially wavefront-guided approaches. Chalazion excision could reduce ocular aberrations and is recommended before refractive surgeries.

  16. Ocular Straylight with Different Multifocal Contact Lenses.

    Science.gov (United States)

    Łabuz, Grzegorz; López-Gil, Norberto; van den Berg, Thomas J T P; Vargas-Martín, Fernando

    2017-04-01

    Multifocal contact lenses have been growing in popularity as a modality to correct presbyopic eyes, although visual side effects such as disability glare have been reported. The objective of this study was to investigate the effect of multifocal contact lenses on disability glare by means of ocular straylight. A prospective randomized, comparative study was performed that included 16 subjects free of ocular pathology. Straylight was measured using a commercial straylight meter with the natural and dilated pupil. Participants were fitted with Proclear Multifocal (Distance/Near), ACUVUE Oasys for Presbyopia, and Air Optix Aqua Multifocal randomized to the left or right eye. Straylight measurements were repeated with the contact lens in situ after the pupil dilation. Results obtained with the dilated pupil without contact lens acted as a control. Diameter of the natural and dilated pupil was 2.87 ± 0.40 mm and 7.45 ± 0.86 mm, respectively (P lenses, a significant difference was only found between Air Optix and the control group (P = .006). The latter showed also slightly increased light scatter. A difference in measured straylight was found between the studied multifocal lenses. The observed variability and the straylight-pupil size dependency should be taken into account to avoid elevated straylight in multifocal contact lens wearers. The reason for the observed differences in straylight must be the subject of future studies.

  17. Ocular toxoplasmosis in immunosuppressed nonhuman primates

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    Holland, G.N.; O' Connor, G.R.; Diaz, R.F.; Minasi, P.; Wara, W.M.

    1988-06-01

    To investigate the role of cellular immunodeficiency in recurrent toxoplasmic retinochoroiditis, six Cynomolgus monkeys (Macaca fascicularis) with healed toxoplasmic lesions of the retina were immunosuppressed by total lymphoid irradiation. Three months prior to irradiation 30,000 Toxoplasma gondii organisms of the Beverley strain had been inoculated onto the macula of eye in each monkey via a pars plana approach. Toxoplasmic retinochoroiditis developed in each animal, and lesions were allowed to heal without treatment. During total lymphoid irradiation animals received 2000 centigrays (cGy) over a 7-week period. Irradiation resulted in an immediate drop in total lymphocyte counts and decreased ability to stimulate lymphocytes by phytohemagglutinin. Weekly ophthalmoscopic examinations following irradiation failed to show evidence of recurrent ocular disease despite persistent immunodeficiency. Four months after irradiation live organisms were reinoculated onto the nasal retina of the same eye in each animal. Retinochoroidal lesions identical to those seen in primary disease developed in five of six animals. Toxoplasma organisms therefore were able to proliferate in ocular tissue following the administration of immunosuppressive therapy. This study fails to support the hypothesis that cellular immunodeficiency alone will initiate recurrent toxoplasmic retinochoroiditis. Results suggest that reactivation of disease from encysted organisms involves factors other than suppression of Toxoplasma proliferation. If reactivation occurs by other mechanisms, however, cellular immunodeficiency then may allow development of extensive disease.

  18. Treatment of ocular toxocariasis with albendazole.

    Science.gov (United States)

    Barisani-Asenbauer, T; Maca, S M; Hauff, W; Kaminski, S L; Domanovits, H; Theyer, I; Auer, H

    2001-06-01

    The purpose of this study was to evaluate the efficacy of combined albendazole and steroid treatment for uveitis caused by Toxocara canis in immunocompetent patients. Five patients (7 eyes) with ocular larva migrans syndrome (OLM) were used in this study. Toxocariasis was suspected based on clinical manifestations and confirmed by anti-toxocara IgG and Western blot analysis. Systemic albendazole (adults: 800 mg b.i.d.; children: 400 mg b.i.d.) was given in conjunction with steroids. Visual acuity before and after therapy, inflammatory response, side effects and toxicity were evaluated. Treatment resulted in an improved visual acuity in all patients. Mean initial Snellen visual acuity was 20/40, and mean final acuity was 20/20. There were no recurrences of uveitis throughout the observation period (average: 13.8 months; range: 3 days to 24 months). These findings suggest that albendazole, in combination with systemic steroids, is a useful regimen to treat ocular larva migrans syndrome.

  19. Nanoliposomal minocycline for ocular drug delivery

    Science.gov (United States)

    Kaiser, James M.; Imai, Hisanori; Haakenson, Jeremy K.; Brucklacher, Robert M.; Fox, Todd E.; Shanmugavelandy, Sriram S.; Unrath, Kellee A.; Pedersen, Michelle M.; Dai, Pingqi; Freeman, Willard M.; Bronson, Sarah K.; Gardner, Thomas W.; Kester, Mark

    2012-01-01

    Nanoliposomal technology is a promising drug delivery system that could be employed to improve the pharmacokinetic properties of clearance and distribution in ocular drug delivery to the retina. We developed a nanoscale version of an anionic, cholesterol-fusing liposome that can encapsulate therapeutic levels of minocycline capable of drug delivery. We demonstrate that size extrusion followed by size-exclusion chromatography can form a stable 80-nm liposome that encapsulates minocycline at a concentration of 450 ± 30 μM, which is 2% to 3% of loading material. More importantly, these nontoxic nanoliposomes can then deliver 40% of encapsulated minocycline to the retina after a subconjunctival injection in the STZ model of diabetes. Efficacy of therapeutic drug delivery was assessed via transcriptomic and proteomic biomarker panels. For both the free minocycline and encapsulated minocycline treatments, proinflammatory markers of diabetes were downregulated at both the messenger RNA and protein levels, validating the utility of biomarker panels for the assessment of ocular drug delivery vehicles. PMID:22465498

  20. Serious Visual (Ocular) Complications in Pre-eclampsia and Eclampsia.

    Science.gov (United States)

    Radha Bai Prabhu, Thangappah

    2017-10-01

    Complete loss of vision is an uncommon ocular complication of pre-eclampsia/eclampsia. The conditions which lead to visual loss in pre-eclampsia include cortical blindness, retinal detachment, retinal vascular thrombosis and optic nerve atrophy. The objective was to describe the cause, clinical course and prognosis in blindness complicating pre-eclampsia. This is a prospective observational study conducted at the Govt. Hospital for Women and Children, Chennai, from January 2006 to December 2010. Sixteen women who were diagnosed with blindness complicating pre-eclampsia were analysed for the cause of blindness, clinical details and prognosis. The incidence of blindness among women with pre-eclampsia and eclampsia was 0.17%. The cause of visual loss was cortical blindness in 14 patients and retinal detachment in two patients. Blindness manifested predominantly in the intrapartum and postpartum period in 13/16 cases (81.25%). Seven patients (43.75%) suffered from severe pre-eclampsia, and nine patients (56.25%) suffered from eclampsia. HELLP syndrome, gestational diabetes mellitus (GDM) and anaemia were seen in two patients each. Seven patients also presented with motor deficits. CT scan imaging showed cortical vein thrombosis in five cases, arterial infarcts in two cases, widespread hypodense areas in the occipito-parietal region in six cases. In patients with cortical blindness, recovery of vision occurred within 10 days. Cortical blindness and retinal detachment are rare complications of pre-eclampsia and eclampsia. The prognosis is usually good especially with cortical blindness where the loss of vision is transient. The mainstay of management is effective treatment of pre-eclampsia/eclampsia along with termination of pregnancy.

  1. Ocular components before and after acquired, nonaccommodative esotropia.

    Science.gov (United States)

    Frane, S L; Sholtz, R I; Lin, W K; Mutti, D O

    2000-12-01

    Acquired nonaccommodative esotropia describes the sudden onset of a constant, comitant strabismus of idiopathic origin in children >6 months of age. We present a case of acquired nonaccommodative esotropia at 20 months of age in a subject participating in the Berkeley Infant Biometry Study, a longitudinal study of emmetropization and ocular component development in infants between 3 months and 3 years of age. Ocular components for this child were normal before the onset of strabismus (within 2 SD's of the mean for orthotropic study participants) for refractive error, corneal power, lens radii, lens power, and ocular axial dimensions. Refractive error postsurgically was significantly more hyperopic and crystalline lens power lower than average at +2.38 D and 37.2 D, respectively. The lack of abnormal ocular parameters is consistent with the idiopathic etiology of acute onset esotropia. This case suggests that ocular component values may not be useful for assessing the risk of acquired nonaccommodative esotropia.

  2. Ocular trauma from paintball-pellet war games.

    Science.gov (United States)

    Mason, John O; Feist, Richard M; White, Milton F

    2002-02-01

    We studied ocular injuries and visual outcome after blunt trauma from paintball pellets. We retrospectively reviewed cases of ocular injury from paintball pellets occurring over 32 months. Ten cases of ocular injury from paintball pellets were recorded. Most patients (9) were injured at home or at a friend's home; only 1 was injured at a war game facility. Six patients had surgery. Final visual acuity was 20/25 or better in 6 patients, 20/30 to 20/50 in 2 patients, 20/60 to 20/100 in 2 patients, and 20/200 in 1 patient. Traumatic maculopathy and epiretinal membrane formation were determinants of worse final visual acuity. Paintball pellet ocular injuries occur more frequently at home than at war game facilities. Advanced surgical techniques offer decreased ocular morbidity and improved visual acuity. Decreasing visual morbidity from paintball pellets requires public education, proper product labeling, and packaging of eye protection with all paintball-related products.

  3. Electric motor handbook

    CERN Document Server

    Chalmers, B J

    2013-01-01

    Electric Motor Handbook aims to give practical knowledge in a wide range of capacities such as plant design, equipment specification, commissioning, operation and maintenance. The book covers topics such as the modeling of steady-state motor performance; polyphase induction, synchronous, and a.c. commutator motors; ambient conditions, enclosures, cooling and loss dissipation; and electrical supply systems and motor drives. Also covered are topics such as variable-speed drives and motor control; materials and motor components; insulation types, systems, and techniques; and the installation, sit

  4. Early and late complications of ocular burn injuries.

    Science.gov (United States)

    Cabalag, Miguel S; Wasiak, Jason; Syed, Quaderi; Paul, Eldho; Hall, Anthony J; Cleland, Heather

    2015-03-01

    Ocular involvement in facial burns may lead to significant long-term morbidity. The aims of this study were to analyse the epidemiology, management and outcomes of ocular burn injuries, as well as to identify risk factors for developing early and late ocular complications. A retrospective medical chart review was conducted for 125 patients with ocular burns who were admitted to the Victorian Adult Burns Service (VABS), from November 2000 to January 2010. Univariate analyses was utilised to identify demographic and injury related variables associated with early and late complications. The majority of patients were male (n=101, 80.8%), and the mean (range) age was 40.7 (15-86) years. The most common mechanism was flame burns (n=77, 61.6%), and most were accidental (n=114, 91.2%). Early ocular complications occurred in 50 (40.0% [95% CI: 31.3%-49.1%]) patients, with the commonest being visual loss (n=39, 31.2%). Chemical burns, ocular discomfort, peri-orbital oedema, corneal injury, as well as eyelid and facial burns of increasing severity were associated with developing an early complication. Late ocular complications occurred in 19 (15.2% [95% CI: 9.4%-22.7%]) patients, with visual loss being the most frequent (n=13, 10.4%). Chemical burns, ocular discomfort, corneal injury of increasing severity, visual loss on presentation, ectropion, as well as eyelid burns of increasing depth were associated with late morbidity. Chemical burns, ocular discomfort, as well as corneal injury and eyelid burns of increasing severity were risk factors for both early and late ocular complications. III (retrospective comparative study). Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

  5. PROFILE OF OCULAR TRAUMA IN UTTARAKHAND, A HOSPITAL BASED STUDY.

    Directory of Open Access Journals (Sweden)

    Renu Dhasmana

    2013-01-01

    Full Text Available Background: Although ocular trauma is preventable public health problem throughout the world it is still one of the common causes of ophthalmic morbidity and monocular blindness. There are no published studies on pattern and severity of ocular trauma in Uttarakhand. The present study analyzes the pattern and visual outcome of ocular trauma in this region. Methods: Study design: Prospective hospital-based study. Settings: Patients of ocular trauma presenting to Ophthalmology OPD and emergency department of Himalayan Institute of Medical Sciences, Dehradun. Participants: All ocular injury patients seen for the first time during the period January to December 2008. Results: A total of 88 patients, and 103 eyes, were studied. Men had two fold higher rate of ocular injury than women. The mean age of presentation was 31.2 + 13.6 years (range: 6 - 80 years. The predominant age group of patients was 21-40 years, 55.29 % (n = 47. Eye injuries related to road traffic accident were seen in 37.86% of eyes. Industrial workers were more frequently involved in ocular trauma (23.86%. Closed globe injuries were noted in 55 eyes (53.39% and open globe injuries were noted in 40 eyes (38.83%. Eight eyes (7.76% suffered from chemical injuries. The initial presenting visual acuity of patients with blunt ocular trauma was better than penetrating injury. Eye with better visual acuity at presentation had better visual prognosis at 6 months. Conclusion: Ocular injuries were common in young males. Road traffic accidents related eye injuries were noted in significant number of cases. Strict implementation of traffic rules, health education and preventive strategies may help to decrease the occurrence of ocular injuries.

  6. Ontogeny of mouse vestibulo-ocular reflex following genetic or environmental alteration of gravity sensing.

    Directory of Open Access Journals (Sweden)

    Mathieu Beraneck

    Full Text Available The vestibular organs consist of complementary sensors: the semicircular canals detect rotations while the otoliths detect linear accelerations, including the constant pull of gravity. Several fundamental questions remain on how the vestibular system would develop and/or adapt to prolonged changes in gravity such as during long-term space journey. How do vestibular reflexes develop if the appropriate assembly of otoliths and semi-circular canals is perturbed? The aim of present work was to evaluate the role of gravity sensing during ontogeny of the vestibular system. In otoconia-deficient mice (ied, gravity cannot be sensed and therefore maculo-ocular reflexes (MOR were absent. While canals-related reflexes were present, the ied deficit also led to the abnormal spatial tuning of the horizontal angular canal-related VOR. To identify putative otolith-related critical periods, normal C57Bl/6J mice were subjected to 2G hypergravity by chronic centrifugation during different periods of development or adulthood (Adult-HG and compared to non-centrifuged (control C57Bl/6J mice. Mice exposed to hypergravity during development had completely normal vestibulo-ocular reflexes 6 months after end of centrifugation. Adult-HG mice all displayed major abnormalities in maculo-ocular reflexe one month after return to normal gravity. During the next 5 months, adaptation to normal gravity occurred in half of the individuals. In summary, genetic suppression of gravity sensing indicated that otolith-related signals might be necessary to ensure proper functioning of canal-related vestibular reflexes. On the other hand, exposure to hypergravity during development was not sufficient to modify durably motor behaviour. Hence, 2G centrifugation during development revealed no otolith-specific critical period.

  7. Ontogeny of mouse vestibulo-ocular reflex following genetic or environmental alteration of gravity sensing.

    Science.gov (United States)

    Beraneck, Mathieu; Bojados, Mickael; Le Séac'h, Anne; Jamon, Marc; Vidal, Pierre-Paul

    2012-01-01

    The vestibular organs consist of complementary sensors: the semicircular canals detect rotations while the otoliths detect linear accelerations, including the constant pull of gravity. Several fundamental questions remain on how the vestibular system would develop and/or adapt to prolonged changes in gravity such as during long-term space journey. How do vestibular reflexes develop if the appropriate assembly of otoliths and semi-circular canals is perturbed? The aim of present work was to evaluate the role of gravity sensing during ontogeny of the vestibular system. In otoconia-deficient mice (ied), gravity cannot be sensed and therefore maculo-ocular reflexes (MOR) were absent. While canals-related reflexes were present, the ied deficit also led to the abnormal spatial tuning of the horizontal angular canal-related VOR. To identify putative otolith-related critical periods, normal C57Bl/6J mice were subjected to 2G hypergravity by chronic centrifugation during different periods of development or adulthood (Adult-HG) and compared to non-centrifuged (control) C57Bl/6J mice. Mice exposed to hypergravity during development had completely normal vestibulo-ocular reflexes 6 months after end of centrifugation. Adult-HG mice all displayed major abnormalities in maculo-ocular reflexe one month after return to normal gravity. During the next 5 months, adaptation to normal gravity occurred in half of the individuals. In summary, genetic suppression of gravity sensing indicated that otolith-related signals might be necessary to ensure proper functioning of canal-related vestibular reflexes. On the other hand, exposure to hypergravity during development was not sufficient to modify durably motor behaviour. Hence, 2G centrifugation during development revealed no otolith-specific critical period.

  8. Finding centre: ocular and fMRI investigations of bisection and landmark task performance.

    Science.gov (United States)

    Cavézian, Céline; Valadao, Derick; Hurwitz, Marc; Saoud, Mohamed; Danckert, James

    2012-02-09

    The line bisection task is used as a bedside test of spatial neglect patients who typically bisect lines to the right of true centre. To disambiguate the contribution of perceptual from motor biases in bisection, previous research has used the landmark task in which participants determine whether a transection mark is left or right of centre. One recent study using stimuli that reliably leads to leftward perceptual biases in healthy individuals, found that ocular judgements of centre were biased to the right of centre, whereas manual bisections were biased leftwards. Here we used behavioural measures and functional MRI in healthy individuals to investigate ocular and perceptual judgements of centre. Ocular judgements were made by having participants fixate the centre of a horizontal bar that was dark at one end and light at the other (i.e., a 'greyscale' stimulus), whereas perceptual responses were made by having participants indicate whether a transection mark on the greyscales stimuli was to the left or right of centre. Behavioural data indicated a leftward bias in the first, second and longest fixations for bisection. Moreover, greyscale orientation (i.e., dark extremity to the right or to the left), and stimulus position modulated fixations. In contrast, for the landmark task, initial fixations were attracted towards the transection mark, whereas subsequent fixations were closer to veridical centre. Imaging data showed a large bilateral network, including superior parietal and lingual cortex, that was active for bisection. The landmark task activated a predominantly right hemisphere network including superior and inferior parietal cortices. Taken together these results indicate that very different strategies and underlying neural networks are invoked by the bisection and landmark tasks. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Traumatic brain injury and vestibulo-ocular function: current challenges and future prospects

    Directory of Open Access Journals (Sweden)

    Wallace B

    2016-09-01

    Full Text Available Bridgett Wallace,1–4 Jonathan Lifshitz4–8 1360 Balance and Hearing, Department of Physical Therapy, Austin, TX, 2Concussion Health, Department of Clinical Education, Austin, TX, 3Conquering Concussions, Scottsdale, AZ, 4Barrow Neurological Institute at Phoenix Children’s Hospital, Phoenix, AZ, 5Department of Child Health, University of Arizona College of Medicine-Phoenix, Phoenix, AZ, 6The CACTIS Foundation, Scottsdale, 7Phoenix VA Healthcare System, Phoenix, AZ, 8Department of Psychology, Arizona State University, Tempe, AZ, USA Abstract: Normal function of the vestibulo-ocular reflex (VOR coordinates eye movement with head movement, in order to provide clear vision during motion and maintain balance. VOR is generated within the semicircular canals of the inner ear to elicit compensatory eye movements, which maintain stability of images on the fovea during brief, rapid head motion, otherwise known as gaze stability. Normal VOR function is necessary in carrying out activities of daily living (eg, walking and riding in a car and is of particular importance in higher demand activities (eg, sports-related activities. Disruption or damage in the VOR can result in symptoms such as movement-related dizziness, blurry vision, difficulty maintaining balance with head movements, and even nausea. Dizziness is one of the most common symptoms following traumatic brain injury (TBI and is considered a risk factor for a prolonged recovery. Assessment of the vestibular system is of particular importance following TBI, in conjunction with oculomotor control, due to the intrinsic neural circuitry that exists between the ocular and vestibular systems. The purpose of this article is to review the physiology of the VOR and the visual-vestibular symptoms associated with TBI and to discuss assessment and treatment guidelines for TBI. Current challenges and future prospects will also be addressed. Keywords: traumatic brain injury, concussion, vestibular, ocular

  10. Catechol-O-methyltransferase inhibition alters pain and anxiety-related volitional behaviors through activation of β-adrenergic receptors in the rat.

    Science.gov (United States)

    Kline, R H; Exposto, F G; O'Buckley, S C; Westlund, K N; Nackley, A G

    2015-04-02

    Reduced catechol-O-methyltransferase (COMT) activity resulting from genetic variation or pharmacological depletion results in enhanced pain perception in humans and nociceptive behaviors in animals. Using phasic mechanical and thermal reflex tests (e.g. von Frey, Hargreaves), recent studies show that acute COMT-dependent pain in rats is mediated by β-adrenergic receptors (βARs). In order to more closely mimic the characteristics of human chronic pain conditions associated with prolonged reductions in COMT, the present study sought to determine volitional pain-related and anxiety-like behavioral responses following sustained as well as acute COMT inhibition using an operant 10-45°C thermal place preference task and a light/dark preference test. In addition, we sought to evaluate the effects of sustained COMT inhibition on generalized body pain by measuring tactile sensory thresholds of the abdominal region. Results demonstrated that acute and sustained administration of the COMT inhibitor OR486 increased pain behavior in response to thermal heat. Further, sustained administration of OR486 increased anxiety behavior in response to bright light, as well as abdominal mechanosensation. Finally, all pain-related behaviors were blocked by the non-selective βAR antagonist propranolol. Collectively, these findings provide the first evidence that stimulation of βARs following acute or chronic COMT inhibition drives cognitive-affective behaviors associated with heightened pain that affects multiple body sites. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  11. [Late complications after chemical burns of the ocular surface. Surgical strategies for ocular surface reconstruction].

    Science.gov (United States)

    Bachmann, B; Cursiefen, C

    2011-10-01

    Severe chemical burns of the ocular surface frequently result in long-standing and ongoing disorders of the conjunctiva and the cornea including conjunctival scarring with shortening of the fornix, cicatricial entropion, complications caused by trichiasis and scarring or chronic ulceration of the cornea. Advanced destruction of limbal stem cells leads to limbal stem cell deficiency with conjunctivalization of the cornea. Surgical therapy aims at the correction of malpositioning of the lids, the reconstruction of the conjunctiva and the fornix utilizing applicable tissue grafts and the reestablishment of a stable, avascular and transparent corneal epithelium by e.g. transplantation of epithelial stem cells. Progressive corneal ulcerations unresponsive to medical therapy can be treated by amniotic membrane transplantation, corneal transplantation or by conjunctival covering depending on the extent of damaged tissue. The surgical therapy of patients after severe chemical burns of the ocular surface is generally performed in specialized centers and occasionally requires a multidisciplinary approach.

  12. Iontoforese no transporte ocular de drogas Iontophoresis for ocular drug delivery

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    Sílvia Ligório Fialho

    2004-10-01

    Full Text Available O método mais comum de administração de drogas no olho é por meio de colírios. Entretanto, por este método, não é possível atingir a concentração terapêutica nos fluidos e tecidos posteriores do olho. A administração sistêmica apresenta reduzido acesso ao segmento posterior do olho devido à presença das barreiras oculares. Injeções subconjuntivais e retrobulbares não são capazes de proporcionar níveis adequados da droga, e a injeção intravítrea é método invasivo, inconveniente e que apre-senta riscos de perfuração do bulbo ocular ou descolamento da retina. A iontoforese, no entanto, apresenta-se como alternativa para o transporte de doses terapêuticas de drogas para o segmento posterior do olho. A iontoforese é uma técnica que consiste na administração de drogas para o organismo através dos tecidos, utilizando um campo elétrico. O eletrodo ativo, que se encontra em contato com a droga, é colocado no local a ser tratado, e um segundo eletrodo, com a finalidade de fechar o circuito elétrico, é colocado em outro local do organismo. O campo elétrico facilita o transporte da droga, que deve se encontrar, preferencialmente, na forma ionizada. A iontoforese pode ser considerada como um método seguro e não invasivo de transporte de drogas para locais específicos do olho. Aplicada experimentalmente para o tratamento de doenças oculares, esta técnica tem evoluído muito nos últimos anos e, atualmente, testes clínicos de fase III encontram-se em andamento.The most traditional method of ocular drug delivery is through the use of eyedrops. However, by this method, the therapeutic concentration in deep ocular fluids and tissues can not be efficiently reached. Systemic administration presents poor access to the posterior segment of the eye due to ocular barriers. Subconjuntival and retrobulbar injections are not able to produce adequate levels of the drug, and intravitreal injection is an invasive and problematic

  13. Consideraciones del trauma ocular infantil Considerations on the ocular trauma in children

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    Alejandro Arias Díaz

    2012-01-01

    Full Text Available Se realizó una descripción de los aspectos clínicos y el manejo terapéutico del trauma ocular en edades pediátricas. Se identifican las particularidades a abordar en estos pacientes con presencia de cataratas traumáticas y/o heridas penetrantes corneales, por las diferencias en el manejo de las mismas en estas edades y en la adultez. Se hace énfasis en el hifema traumático.The clinical aspects and the treatment management of the ocular trauma at pediatric ages were described. Those particularities to be taken into account when approaching these patients who suffer traumatic cataracts and/or penetrating corneal injuries were indentified, on the account of the differences in the management of this disease between children and adults. Emphasis was made on the description of traumatic hyphema.

  14. TNF-Related Apoptosis Inducing Ligand in Ocular Cancers and Ocular Diabetic Complications

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    Paolo Perri

    2015-01-01

    Full Text Available TNF-related apoptosis inducing ligand (TRAIL is an intensively studied cytokine, in particular for its anticancer activity. The discovery that conjunctival sac fluid contains extremely high levels of soluble TRAIL as compared to other body fluids suggested important implications in the context of the immunological surveillance of the eye, in particular of the anterior surface. In this review, we discuss the potential physiopathologic and therapeutic role of the TRAIL/TRAIL receptor system in a variety of ocular cancers. Moreover, since an increasing amount of data has indicated the important biological activities of the TRAIL/TRAIL receptor systems also in a completely different pathologic context such as diabetes mellitus, in the second part of this review we summarize the currently available data on the involvement of TRAIL in the ocular complications of diabetes mellitus as modulator of the inflammatory and angiogenic response in the eye.

  15. TNF-related apoptosis inducing ligand in ocular cancers and ocular diabetic complications.

    Science.gov (United States)

    Perri, Paolo; Zauli, Giorgio; Gonelli, Arianna; Milani, Daniela; Celeghini, Claudio; Lamberti, Giuseppe; Secchiero, Paola

    2015-01-01

    TNF-related apoptosis inducing ligand (TRAIL) is an intensively studied cytokine, in particular for its anticancer activity. The discovery that conjunctival sac fluid contains extremely high levels of soluble TRAIL as compared to other body fluids suggested important implications in the context of the immunological surveillance of the eye, in particular of the anterior surface. In this review, we discuss the potential physiopathologic and therapeutic role of the TRAIL/TRAIL receptor system in a variety of ocular cancers. Moreover, since an increasing amount of data has indicated the important biological activities of the TRAIL/TRAIL receptor systems also in a completely different pathologic context such as diabetes mellitus, in the second part of this review we summarize the currently available data on the involvement of TRAIL in the ocular complications of diabetes mellitus as modulator of the inflammatory and angiogenic response in the eye.

  16. Headaches with ocular localization and involvement Cefaleas de localización y compromiso oculares

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    Marta Lucía Muñoz Cardona

    2005-04-01

    Full Text Available The most frequent primary headaches, including migraine variants, and intrinsic optic nerve disorders that produce headache, are reviewed. The latter are often accompanied by autonomic nervous system alterations which lead to vasomotor changes, frequently present in neuralgic processes known as headaches with disautonomic involvement. Epidemiological, semiological, clinical, and therapeutical aspects of different cranial, facial and ocular diseases that produce headache are included. Some physiopathological elements that may help to analyze painful craniofacial processes are discussed. Secondary headaches and common facial neuralgias, on the other hand, are also considered because they may confuse the differential diagnosis. Se revisan las cefaleas primarias más frecuentes que comprometen las estructuras oculares y vecinas al globo ocular, las variantes de la migraña y las alteraciones propias del nervio óptico que alteran la función visual y que se acompañan no solamente de síntomas dolorosos sino también de trastornos vasomotores debidos a alteraciones del sistema nervioso autónomo que suelen ser comunes en algunos procesos neurálgicos llamados ahora cefaleas con compromiso disautonómico. En este artículo se comentan los elementos epidemiológicos de las diferentes enfermedades craneales, faciales y oculares que cursan con cefalea; las diferencias clínicas entre las mismas y su presentación semiológica, al igual que algunos elementos terapéuticos. Se discuten además algunos elementos fisiopatológicos de gran utilidad en el análisis de los procesos dolorosos craneofaciales y el perfil temporal de los mismos; también se comentan algunas cefaleas secundarias que comparten con las primarias elementos que se prestan a confusión en la clínica. Finalmente, se hace un análisis de las neuralgias faciales comunes.

  17. Pattern of ocular tumors in the eastern region of Nepal.

    Science.gov (United States)

    Lavaju, P; Arya, S K; Sinha, A; Pandey, S; Adhikari, S; Shrestha, B G; Chetan, S; Agarwal, T L

    2009-01-01

    ocular tumors are commonly encountered in ophthalmic practice. to study the clinical pattern of ocular tumors in the eastern region of Nepal. the hospital records of patients with ocular tumors treated at B P Koirala Institute of Health Sciences in the eastern region of Nepal over a period of 5 years (April 2003 - March 2008) were studied retrospectively. of 115 consecutive patients with ocular tumors, 40 (34.75%) were below the age of 21 years, 41 (35.65%) were in the age group of 21-50 years and 34 (29.56%) of age above 50 years. There were 48 (41.73%) and 67 (58.26%) patients with benign and malignant tumors respectively. The common benign tumors were conjunctival papilloma, dermoid cysts, nevus, cystic lesions and hemangioma. Among the malignant tumors, basal cell carcinoma was the commonest (22.38%). Retinoblastoma was the most common ocular malignant tumor in the pediatric age group (88.8%). Basal cell carcinoma was the commonest eyelid malignancy (53.57%). conjunctival papilloma, dermoid cysts, nevus, cystic lesions and hemangioma are common benign ocular tumors, whereas basal cell carcinoma and retinoblastoma are the commonest ocular malignancies in adults and children respectively.

  18. A multidisciplinary approach for rehabilitation following ocular trauma

    Directory of Open Access Journals (Sweden)

    Pradeep Kumar

    2014-11-01

    Full Text Available Ocular trauma is a very common incidence that occurs in up to 67% of patients with maxillofacial trauma. It results in life-long agony of not being like others with two eyes, which can see and admire the nature's beauty. This article reports on a case of a 23-year-old male patient with phthisis bulbi, resulting from ocular trauma. The patient was rehabilitated aesthetically by fabrication of custom-made ocular prosthesis for his traumatically injured right eye. The patient was pleased with the aesthetic outcome, comfort, and mobility offered by the custom ocular prosthesis. There were no complications with regard to health of underlying residual ocular tissues and there was no need of relining of the prosthesis at 6 month recall appointment. Rehabilitation of patients with ocular trauma requires a multidisciplinary approach involving ophthalmologist, psychologist, and skilled maxillofacial prosthodontist. Custom-made ocular prosthesis fitted over the phthisical globe seems to be a highly positive, logical, noninvasive, and beneficial approach to increase mobility to the prosthesis, improve the cosmetic appearance and psychological well-being of the patient.

  19. Influence of ocular perfusion pressure fluctuation on glaucoma

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    Min-Zi Ren

    2015-12-01

    Full Text Available AIM:To investigate the influence of ocular perfusion pressure fluctuation on glaucoma. METHODS:Forty patients with primary open angle glaucoma from January 2013 to June 2015 in our hospital were used as observation group and 40 families were used as control group. Circadian fluctuation of intraocular pressure, blood pressure and ocular perfusion pressure in 24h were determined to obtain systolic ocular perfusion pressure(SOPP, diastolic ocular perfusion pressure(DOPPand mean ocular perfusion pressure(MOPP. Pearson linear correlation was used to analyze the correlation of circadian MOPP fluctuation with cup-disc ratio, mean defect(MDand the picture standard deviation(PSD. RESULTS:The fluctuation of MOPP, SOPP and DOPP of observation group were significantly higher than those of control group(Pr=-0.389, 95%CI:-0.612~-0.082; P=0.011, was positively correlated with PSD(r=0.512, 95%CI:0.139 ~0.782; P=0.008; no correlation was found between it and the vertical cup-disc ratio(r=0.115, 95%CI:0.056~0.369; P=0.355. CONCLUSION:Ocular perfusion pressure fluctuations in patients with primary open angle glaucoma may reflect the severity of the disease and may make the situation aggravating. Therefore through perfusion pressure monitor in 24h may help us understand the ocular blood flow and the development of primary open-angle glaucoma.

  20. Sighting ocular dominance magnitude varies with test distance.

    Science.gov (United States)

    Ho, Raymond; Thompson, Benjamin; Babu, Raiju J; Dalton, Kristine

    2017-10-31

    Ocular dominance can be defined as the preference of an individual for viewing with one eye over the other for particular visual tasks. It is relevant to monovision contact lens wear, cataract surgery and sports vision. Clinically, the measurement of ocular dominance is typically done at an arbitrary distance using a sighting test, such as the hole-in-card method that has a binary outcome. We investigated the effect of test distance on ocular dominance measured using a binocular sighting test that provided a continuous measurement of dominance. Ten participants with normal binocular vision took part in this study. Their binocular sighting ocular dominance and phorias were measured at one, two, four, eight and 10 metres. During the dominance tests participants made a binocular alignment judgment and then were asked to indicate the relative alignment of each eye using a visual analogue scale as a reference. Eight participants had strong ocular dominance (five right, three left). For these participants, there was a significant increase in the magnitude of dominance with increasing test distance (p  0.05), despite changes in convergence demand. When ocular dominance is present, its magnitude varies significantly with test distance. This has significant implications for the accurate measurement of ocular dominance in the clinic and may reflect the neural processes that influence eye preference. © 2017 Optometry Australia.

  1. Ocular Jellyfish Stings: Report of 2 Cases and Literature Review.

    Science.gov (United States)

    Mao, Chen; Hsu, Chien-Chin; Chen, Kuo-Tai

    2016-09-01

    An ocular jellyfish sting is an ophthalmic emergency and is rarely reported in the medical literature. With the evolution of aquatic activities and entertainment in recent decades, we anticipate that more patients with ocular jellyfish stings may be taken to the emergency department. However, most physicians are unaware of the typical presentations, suitable treatments, prognosis, and possible complications of ocular jellyfish stings. We reported 2 cases with ocular jellyfish stings and collected cases series from literature review. The most common clinical features of ocular jellyfish stings were pain, conjunctival injection, corneal lesion, and photophobia. All patients who sustained ocular stings did so during aquatic activities, and the best management at the scene was proper analgesics and copious irrigation of affected eyes with seawater or saline. The ocular lesions were treated with topical cycloplegics, topical steroids, topical antibiotics, topical antihistamines, and removal of nematocysts. The prognosis was good, and all patients recovered without any permanent sequelae. However, symptoms in some patients may last longer than 1 week. Reported complications included iritis, increased intraocular pressures, mydriasis, decreased accommodation, and peripheral anterior synechiae. Copyright © 2016 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

  2. [Basic immunology and current therapeutic concepts in ocular allergy].

    Science.gov (United States)

    Gehlsen, U; Cursiefen, C; Steven, P

    2014-05-01

    Ocular allergy belongs to the most common ocular diseases globally. Following clinical phenotype and immunopathogenesis different forms of allergy are distinguished, which require different forms of therapeutic approach. This manuscript reviews the basic immunological processes involved in the development of ocular allergies and current and future therapeutic approaches. Results of a literature search in PubMed and our own clinical and experimental experience are presented. In the immunopathogenesis of ocular allergy different immune cells such as dendritic cells, B-cells, T-cells, mast cells, eosinophils and regulatory T-cells are involved. Therapeutic approaches focus on either relief of symptoms using antihistamins or mast cell stabilisers or combinations of both. In severe cases steroids or calcineurin inhibitors are used. Despite great progress in the investigation of ocular allergy in the past decade several open questions remain, such as the relation of ocular allergy with dry eye disease. Future therapeutic approaches will likely be based on recently identified new aspects such as lymphangiogenesis and will allow better and potentially causal treatment of ocular allergy. Georg Thieme Verlag KG Stuttgart · New York.

  3. Ocular complications in children and adolescents following renal transplantation.

    Science.gov (United States)

    Krause, Irit; Snir, Moshe; Cleper, Roxana; Fraser, Abigail; Kovalski, Yael; Axer Siegel, Ruth; Bar-Nathan, Nathan; Davidovits, Miriam

    2010-02-01

    Ocular complications after renal transplantation are common in adults. Nevertheless, data regarding these complications in children are insufficient. The purpose of the present study was to assess ocular morbidity in pediatric renal graft recipients. A retrospective observational study of 71 patients aged 11.2 +/- 5.5 yr was conducted. Mean duration of follow-up was 5.6 +/- 3.5 yr. A total of 16 ocular complications were found in 12 (17%) of the patients. Three patients suffered from more than one complication. Cataract was the most common finding (six patients, 8.4%) followed by swollen disk and hypertensive retinopathy in four patients (5.7%) each and increased intra-ocular pressure in two patients (3%). Mean time interval between transplantation and occurrence of first abnormal ocular finding was 37 +/- 34.5 months. The follow-up time was significantly longer in patients with ophthalmological problems than in those without complications (7.8 yr vs. 5.2 yr, p < 0.02). No statistically significant association was found between the occurrence of ocular complications and the age of the patients at transplantation, donor source, duration of dialysis prior to transplantation, previous corticosteroid therapy or presence of acute rejection episodes. The results of the study point to the importance of regular concurrent ophthalmological follow-up in pediatric renal graft recipients to reduce/prevent ocular morbidity. (c) 2009 Wiley Periodicals, Inc.

  4. Electric Motor Thermal Management

    Energy Technology Data Exchange (ETDEWEB)

    Bennion, Kevin S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-01

    Thermal management enables more efficient and cost-effective motors. This Annual Merit Review presentation describes the technical accomplishments and progress in electric motor thermal management R&D over the last year. This project supports a broad industry demand for data, analysis methods, and experimental techniques to improve and better understand motor thermal management.

  5. The ocular renin-angiotensin system: a therapeutic target for the treatment of ocular disease.

    Science.gov (United States)

    Giese, Michael J; Speth, Robert C

    2014-04-01

    The renin-angiotensin system (RAS) is most well-known for its role in regulation and dysregulation of blood pressure as well as fluid and electrolyte homeostasis. Due to its ability to cause cardiovascular disease, the RAS is the target of a multitude of drugs that antagonize its pathophysiological effects. While the "classical" RAS is a systemic hormonal system, there is an increasing awareness of the existence and functional significance of local RASs in a number of organs, e.g., liver, kidney, heart, lungs, reproductive organs, adipose tissue and adrenal. The eye is one of these organs where a compelling body of evidence has demonstrated the presence of a local RAS. Individual components of the RAS have been shown to be present in many structures of the eye and their potential functional significance in ocular disease states is described. Because the eye is one of the most important and complex organs in the body, this review also discusses the implications of dysregulation of the systemic RAS on the pathogenesis of ocular diseases and how pharmacological manipulation of the RAS might lead to novel or adjunctive therapies for ocular disease states. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. Case of multiple sulfatase deficiency and ocular albinism: a diagnostic odyssey.

    Science.gov (United States)

    Prasad, Chitra; Rupar, C Anthony; Campbell, Craig; Napier, Melanie; Ramsay, David; Tay, K Y; Sharan, Sapna; Prasad, Asuri N

    2014-09-01

    Multiple sulfatase deficiency (MSD) is a rare autosomal recessive inborn error of lysosomal metabolism. The clinical phenotypic spectrum encompasses overlapping features of variable severity and is suggestive of individual single sulfatase deficiencies (i.e., metachromatic leukodystrophy, mucopolysaccharidosis, and X-linked ichthyosis). We describe a 3-year-old male with severe hypotonia, developmental regression and progressive neurodegeneration, coarse facial features, nystagmus (from ocular albinism), and dysmyelinating motor sensory neuropathy. Ethics approval was obtained from the Western University Ontario. Extensive investigative work-up identified deficiencies of multiple sulfatases: heparan sulfate sulfamidase: 6.5 nmoles/mg/protein/17 hour (reference 25.0-75.0), iduronate-2-sulfate sulfatase: 9 nmol/mg/protein/4 hour (reference 31-110), and arylsulfatase A: 3.8 nmoles/hr/mg protein (reference 22-50). The identification of compound heterozygous pathogenic mutations in the SUMF1 gene c.836 C>T (p.A279V) and c.1045C>T (p.R349W) confirmed the diagnosis of MSD. The complex clinical manifestations of MSD and the unrelated coexistence of ocular albinism as in our case can delay diagnosis. Genetic counselling should be provided to all affected families.

  7. Atypical case of ocular hemosiderosis: leopard cataract.

    Science.gov (United States)

    Masket, Samuel; Ceran, Basak Bostanci

    2011-10-01

    We present an interventional case report of an 83-year-old woman who developed ocular hemosiderosis secondary to massive retinal and intravitreal bleeding associated with a choroidal neovascular membrane as a result of age-related macular degeneration. Anterior segment manifestations included low-grade inflammation, posterior synechiae, reversible hyperchromic heterochromia, and a mature cataract with "leopard spots." The longstanding vitreous hemorrhage was thought to be the etiology of these findings. At the request of the vitreoretinal surgeon, cataract surgery was performed to provide visualization of the posterior segment. However, the patient's visual potential was limited by her underlying retinal pathology. Neither author has a financial or proprietary interest in any material or method mentioned. Additional disclosure is found in the footnotes. Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  8. Unusual Presentation of Cutaneous Leishmaniasis: Ocular Leishmaniasis

    Directory of Open Access Journals (Sweden)

    Masoud Doroodgar

    2017-01-01

    Full Text Available The leishmaniases are parasitic diseases that are transmitted to humans by infected female sandflies. Cutaneous leishmaniasis (CL is one of 3 main forms of the disease. CL is the most common form of the disease and is endemic in many urban and rural parts of Iran and usually caused by two species of Leishmania: L. major and L. tropica. We report a case of unusual leishmaniasis with 25 lesions on exposed parts of the body and right eyelid involvement (ocular leishmaniasis. The patient was a 75-year-old male farmer referred to health care center in Aran va Bidgol city. The disease was diagnosed by direct smear, culture, and PCR from the lesions. PCR was positive for Leishmania major.

  9. OCULAR PATHOLOGY IN PATIENTS AFTER KIDNEY TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    L. K. Moshetova

    2011-01-01

    Full Text Available Structural changes in eyes are present in all patients with chronic kidney disease. A study to detect ocular patho- logy in patients with end-stage chronic renal failure after kidney transplantation in the early and late postopera- tive period compared with patients receiving replacement therapy with hemodialysis. Revealed that in the early post-transplant period in recipients of kidneyas in patients on hemodialysis, continued angioretinopatiya, 40% of patients had «dry eye syndrome». In the delayed post-transplant period, patients showed significant impro- vement in the retina and retinal vessels, the improvement of spatial-temporal parameters of visual perception. However, a decrease of visual acuity on the background of the development of posterior subcapsular cataract caused by prolonged corticosteroid, and an increased incidence of viral and bacterial conjunctivitis. 

  10. Optic disc size in ocular hypertension

    Directory of Open Access Journals (Sweden)

    Chandra Sekhar G

    1999-01-01

    Full Text Available Purpose: To study the optic disc size in eyes with ocular hypertension (OHT in comparison to primary open-angle glaucoma (POAG and normals. Methods: Optic disc photographs obtained with the Nidek 3dx NM camera were digitized (Nikon™ coolscan and disc area calculated using Littmann correction in a randomly chosen eye of 28 OHT, 42 POAG and 30 normal subjects. OHT was defined as increased intraocular pressure with no disc or field changes suggestive of glaucoma with open angles. Results: The optic disc area in OHT was 9.47 ± 1.09 mm2; 12.27 ± 2.87mm2 in POAG; and 12.11 ± 2.83 mm2 in normal individuals. Conclusion: Using magnification corrected morphometry and the criteria for OHT diagnosis, the optic disc area in OHT was significantly smaller (p<0.0001 in POAG and normals.

  11. [Macular hole associated with paintball ocular trauma].

    Science.gov (United States)

    Michalewska, Zofia; Michalewski, Janusz; Nawrocka, Zofia; Nawrocki, Jerzy

    2007-01-01

    A presentation of two patients with macular hole after ocular trauma due to paintball. HRT, OCT, SOCT and visual field examinations were performed preoperatively and on 3 postoperative visits. Patients underwent pars plana vitrectomy with trypan blue staining. Final visual acuity 0.6 was achieved in the first patient 6 months after surgery. Best corrected visual acuity 0.2 was achieved in the second patient 3 months after surgery. Macular hole closure was observed on OCT, SOCT, HRT and indirect ophthalmoscopy examination. Pars plana vitrectomy with trypan blue staining and fluid-air exchange is a safe procedure in posttraumatic macular holes. HRT, Oct and SOCT are valuable tools for diagnosis of macular holes and for control after surgical intervention.

  12. Cerebral palsy characterization by estimating ocular motion

    Science.gov (United States)

    González, Jully; Atehortúa, Angélica; Moncayo, Ricardo; Romero, Eduardo

    2017-11-01

    Cerebral palsy (CP) is a large group of motion and posture disorders caused during the fetal or infant brain development. Sensorial impairment is commonly found in children with CP, i.e., between 40-75 percent presents some form of vision problems or disabilities. An automatic characterization of the cerebral palsy is herein presented by estimating the ocular motion during a gaze pursuing task. Specifically, After automatically detecting the eye location, an optical flow algorithm tracks the eye motion following a pre-established visual assignment. Subsequently, the optical flow trajectories are characterized in the velocity-acceleration phase plane. Differences are quantified in a small set of patients between four to ten years.

  13. Achados oculares em pacientes com mucopolissacaridoses

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    Flávia Silva Villas-Bôas

    2011-12-01

    Full Text Available OBJETIVO: O objetivo deste estudo foi determinar a prevalência e gravidade das complicações oculares em pacientes com mucopolissacaridoses (MPS. MÉTODOS: Vinte e nove pacientes com diagnóstico de mucopolissacaridoses foram estudados. Foram avaliados: idade, sexo, acuidade visual, presença de estrabismo, erros refrativos, exame de fundo de olho, pressão intraocular, espessura corneal central e ultrassonografia ocular. RESULTADOS: Foram avaliados três pacientes com MPS I (12%, 11 pacientes com MPS II (37,9%, um paciente com MPS III (3,4% e 14 pacientes com MPS VI (48,3%. A média de idade foi de 9,5 anos (DP 5,5. Observou-se hipermetropia em 88,5% (23 pacientes e astigmatismo em 51,7% (15 pacientes. A média da acuidade visual corrigida foi de 0,45 logMAR (DP 0,68. A média do equivalente esférico foi +3,57 D (DP 2,46 e da pressão intraocular foi 17 mmHg (DP 3,9. Os achados mais comuns foram: espessamento palpebral 24,1% (7 pacientes; opacidade da córnea, 55,2% dos casos (16 pacientes; atrofia do nervo óptico, 23,1% (6 pacientes; dobras radiais na retina 24% (7 pacientes. O fundo de olho não foi examinado em 3 pacientes devido à opacidade de córnea. A média da espessura do complexo esclera-retina-coroide (ERC medida por ultrassom foi de 1,78 mm (DP 0,51. CONCLUSÃO: Os achados oftalmológicos mais proeminentes foram espessamento palpebral, diminuição da acuidade visual, hipermetropia moderada, opacidade da córnea, dobras radiais na retina perimacular e atrofia do nervo óptico.

  14. Different techniques in fabrication of ocular prosthesis.

    Science.gov (United States)

    Cevik, Pinar; Dilber, Erhan; Eraslan, Oguz

    2012-11-01

    Loss of an eye caused by cancer, trauma, or congenital defect creates a deep psychological impact on an individual's life especially social and professional life. Custom-made prosthesis, compared to stock prosthesis, provides a better fit to the eye socket, better cosmetic results, and less discomfort to the patient in the long term. The main objective of this article was to describe 3 different alternative and practical techniques of fabricating custom-made ocular prosthesis. An impression of anophthalmic socket was made with the addition of cured silicone-based precision impression material in all techniques. A master cast was prepared and duplicated with condensation silicone. A self-cure acrylic resin was polymerized in the silicone model and was fitted into the patient's eye socket. A digital photograph of the patient's iris was made using a digital camera and printed on good-quality photo paper in various shades and sizes in the first and the second techniques. Then the photo paper was coated with PVC so as not to allow any color flowing. The proper iris was then inserted to the acrylic base. The prosthesis was final processed using orthodontic heat polymerizing clear acrylic resin.In the other technique, after the trying-in process with wax pattern, an acrylic base was fabricated using heat polymerizing scleral acrylic resin. The prosthetic iris was fabricated from a transparent contact lens by painting the lens with watercolor paints and attaching it to an acrylic resin with tissue conditioner. The final process was made with heat polymerizing transparent acrylic resin. Custom-made prosthesis allows better esthetic and functional results to the patient in comparison to stock prosthesis. Further follow-up is necessary to check the condition and fit of the ocular prosthesis in such patients.

  15. Novel ocular antihypertensive compounds in clinical trials

    Directory of Open Access Journals (Sweden)

    Chen J

    2011-05-01

    Full Text Available June Chen1, Stephen A Runyan1, Michael R Robinson21Department of Biological Sciences, 2Ophthalmology Clinical Research, Allergan, Inc, Irvine, CA, USAIntroduction: Glaucoma is a multifactorial disease characterized by progressive optic nerve injury and visual field defects. Elevated intraocular pressure (IOP is the most widely recognized risk factor for the onset and progression of open-angle glaucoma, and IOP-lowering medications comprise the primary treatment strategy. IOP elevation in glaucoma is associated with diminished or obstructed aqueous humor outflow. Pharmacotherapy reduces IOP by suppressing aqueous inflow and/or increasing aqueous outflow.Purpose: This review focuses on novel non-FDA approved ocular antihypertensive compounds being investigated for IOP reduction in ocular hypertensive and glaucoma patients in active clinical trials within approximately the past 2 years.Methods: The mode of IOP reduction, pharmacology, efficacy, and safety of these new agents were assessed. Relevant drug efficacy and safety trials were identified from searches of various scientific literature databases and clinical trial registries. Compounds with no specified drug class, insufficient background information, reformulations, and fixed-combinations of marketed drugs were not considered.Results: The investigational agents identified comprise those that act on the same targets of established drug classes approved by the FDA (ie, prostaglandin analogs and β-adrenergic blockers as well as agents belonging to novel drug classes with unique mechanisms of action. Novel targets and compounds evaluated in clinical trials include an actin polymerization inhibitor (ie, latrunculin, Rho-associated protein kinase inhibitors, adenosine receptor analogs, an angiotensin II type 1 receptor antagonist, cannabinoid receptor agonists, and a serotonin receptor antagonist.Conclusion: The clinical value of novel compounds for the treatment of glaucoma will depend

  16. Miller Fisher syndrome mimicking ocular myasthenia gravis.

    Science.gov (United States)

    Anthony, Scott A; Thurtell, Matthew J; Leigh, R John

    2012-12-01

    PURPOSE.: Miller Fisher syndrome (MFS) is a rare immune-mediated neuropathy that commonly presents with diplopia after the acute onset of complete bilateral external ophthalmoplegia. Ophthalmoplegia is often accompanied by other neurological deficits such as ataxia and areflexia that characterize MFS. Although MFS is a clinical diagnosis, serological confirmation is possible by identifying the anti-GQ1b antibody found in most of the affected patients. We report a patient with MFS who presented with clinical signs suggestive of ocular myasthenia gravis but in whom the correct diagnosis was made on the basis of serological testing for the anti-GQ1b antibody. CASE REPORT.: An 81-year-old white man presented with an acute onset of diplopia after a mild gastrointestinal illness. Clinical examination revealed complete bilateral external ophthalmoplegia and left-sided ptosis. He developed more marked bilateral ptosis, left greater than right, with prolonged attempted upgaze. He was also noted to have a Cogan lid twitch. Same day evaluation by a neuro-ophthalmologist revealed mild left-sided facial and bilateral orbicularis oculi weakness. He had no limb ataxia but exhibited a slightly wide-based gait with difficulty walking heel-to-toe. A provisional diagnosis of ocular myasthenia gravis was made, and anticholinesterase inhibitor therapy was initiated. However, his symptoms did not improve, and serological testing was positive for the anti-GQ1b immunoglobulin G antibody, supporting a diagnosis of MFS. CONCLUSIONS.: Although the predominant ophthalmic feature of MFS is complete bilateral external ophthalmoplegia, it should be recognized that MFS has variable associations with lid and pupillary dysfunction. Such confounding neuro-ophthalmic features require a thorough history, neurological examination, neuroimaging, and serological testing for the anti-GQ1b antibody to arrive at a diagnosis of MFS.

  17. Corneal manifestations of ocular demodex infestation.

    Science.gov (United States)

    Kheirkhah, Ahmad; Casas, Victoria; Li, Wei; Raju, Vadrevu K; Tseng, Scheffer C G

    2007-05-01

    To report the corneal manifestations in eyes with Demodex infestation of the eyelids. Noncomparative, interventional case series. This retrospective review included six patients with Demodex blepharitis who also exhibited corneal abnormalities, which led to suspicion of limbal stem cell deficiency in three cases. All patients received weekly lid scrubs with 50% tea tree oil and a daily lid scrubs with tea tree shampoo for a minimum of six weeks. Improvement of symptoms and corneal and conjunctival signs were evaluated. All six patients exhibited ocular irritation and conjunctival inflammation, while meibomian gland dysfunction (n = 5), rosacea (n = 4), and decreased vision (n = 3) also were noted despite prior treatments with oral tetracycline, topical steroids with antibiotics, and lid scrub with baby shampoo. These patients were proven to have Demodex folliculorum (n = 6) and Demodex brevis (n = 3) by microscopic examination of epilated lashes. Their corneal manifestation included superficial corneal vascularization (six eyes of five cases), marginal corneal infiltration (two eyes of two cases), phlyctenule-like lesion (one eye of one case), superficial corneal opacity (two eyes of two cases), and nodular corneal scar (two eyes of two cases). After treatment, the Demodex count was reduced from 6.8 +/- 2.8 to 1 +/- 0.9 (standard deviation; P = .001). All patients showed dramatic resolution of ocular irritation, conjunctival inflammation, and all inflammatory, but not scarred, corneal signs; three patients showed improved vision. A variety of corneal pathologic features together with conjunctival inflammation, commonly noted in rosacea, can be found in patients with Demodex infestation of the eyelids. When conventional treatments for rosacea fail, one may consider lid scrub with tea tree oil to eradicate mites as a new treatment.

  18. Ocular findings in patients with vitiligo: a case- control study

    Directory of Open Access Journals (Sweden)

    Abdollahi A

    2011-02-01

    Full Text Available "nBackground: Vitiligo is a common acquired disorder characterized by depigmented cutaneous patches devoid of melanocytes. The disease carries a risk for ocular abnormalities. Few reports are available about the ocular findings and their possible association with the disease in patients with vitiligo in the literature."n "nMethods: A total of 72 patients with previously documented cutaneous vitiligo were examined for ocular findings and 50 healthy individuals were enrolled as the control group in Razi Hospital in Tehran, Iran during years 2007-2008. Demographic features including age, gender, duration of the disease, presence of any accompanying autoimmune diseases, type of vitiligo and its anatomical distribution were recorded to investigate a possible association between the disease and the ocular findings."n "nResults: Amongst 72 patients with vitiligo, 11 (15.3% had ocular findings including retinal pigment epithelium hypopigmentation, posterior pole pigment changes, peripheral iris atrophy, atrophy of retinal pigment epithelium and iris hyperpigmentation. Amongst the controls, only two cases (4% had ocular findings which consisted of iris hyperpigmentation. The relationship between ocular findings and vitiligo was statistically significant (p= 0.04. No other remarkable features, such as age, gender, age at the onset of the disease, type of vitiligo, presence of priorbital lesions or body surface area involvement by the disease, were suggestive of an association or presenting a risk factor for vitiligo."n "nConclusion: Although the sample size and prevalence of ocular findings were not satisfactory enough to make a definite conclusion, we found a higher occurrence of ocular findings in patients with vitiligo than the control group.

  19. Occupational ocular accidents amongst Greek endodontists: a national questionnaire survey.

    Science.gov (United States)

    Zarra, T; Lambrianidis, T

    2013-08-01

    To investigate amongst Greek endodontists, the incidence of ocular accidents during practice, the circumstances associated with them, the therapeutic measures taken after the accidents, their compliance with the use of eye protection and their eye care behaviour. One hundred and forty-seven endodontists met the inclusion criteria and were invited to participate in the survey. Data were gathered through interviews based on a questionnaire. Participants were asked for personal/professional data, information on ocular accidents in the past 5 years, post-accident actions and the type of eye protection used. Their eyesight status and frequency of ocular examination were also recorded. Data were analysed using chi-square test, independent samples t-test and logistic regression. The level of significance was set at P = 0.05. The response rate was 84%. Ocular accidents were reported by 73% of the participants. Amalgam and NaOCl were the foreign bodies most frequently associated with ocular accidents. Medical assistance was sought in 16% of the most recent accidents. No permanent eye damage was reported. Regular use of magnification (OR:0.305, 95%CI:0.123-0.754) and years of clinical experience (OR:0.191, 95%CI:0.066-0.551) were significant predictors for the incidence of ocular accidents. Adequate eye protection was utilized by 82% of endodontists. Endodontists with eyesight deficiencies attended more frequently for ocular examination (P = 0.018). A high percentage of endodontists experienced ocular accidents. Regular use of magnification and increasing years in practice were associated with a reduced risk of ocular accidents. The majority of endodontists reported using adequate eye protection. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. The horizontal angular vestibulo-ocular reflex: a nonlinear mechanism for context-dependent responses.

    Science.gov (United States)

    Ranjbaran, Mina; Galiana, Henrietta L

    2013-11-01

    Studies of the vestibulo-ocular reflex (VOR) have revealed that this type of involuntary eye movement is influenced by viewing distance. This paper presents a bilateral model for the horizontal angular VOR in the dark based on realistic physiological mechanisms. It is shown that by assigning proper nonlinear neural computations at the premotor level, the model is capable of replicating target-distance-dependent VOR responses that are in agreement with geometrical requirements. Central premotor responses in the model are also shown to be consistent with experimental observations. Moreover, the model performance after simulated unilateral canal plugging also reproduces experimental observations, an emerging property. Such local nonlinear computations could similarly generate context-dependent behaviors in other more complex motor systems.

  1. Prosthetic Rehabilitation of Ocular Defect resulting from Pediatric Retinoblastoma.

    Science.gov (United States)

    Janya, Suma; Gubrellay, Priyanka; Purwar, Anupam; Khanna, Shally

    2014-01-01

    Ocular defects result from tumor, congenital anomaly and external injury not only lead to serious impairment of function and esthetics but also make the patient psychologically disabled. Prosthetic rehabilitation attempts to restore these disfgurements may improve esthetic, level of function, general psychologic improvement and quality of life. This clinical report details an attempt to rehabilitate a pediatric patient who has undergone orbital enucleation resulting from retinoblastoma with the aid of custom ocular prosthesis using commercially available prefabricated eye shell. How to cite this article: Janya S, Gubrellay P, Purwar A, Khanna S. Prosthetic Rehabilitation of Ocular Defect resulting from Pediatric Retinoblastoma. Int J Clin Pediatr Dent 2014; 7(3):209-212.

  2. Ocular toxicity of 2,2,2-trifluoroethanol in rabbits

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, T.C.; Hahn, F.F.; Merickel, B.S.; Hobbs, C.H.

    Three commercial formulations of 2,2,2-trifluoroethanol (TFE) were applied to eyes of rabbits and evaluated for their potential to cause ocular damage. All three products were severe eye irritants and water irrigation shortly after exposure was not effective in reducing ocular damage. Gross and histological observations revealed marked conjunctivitis, moderate to severe ulcerative keratitis, and hyperemia and edema of the iris, all of which showed evidence of resolution over the three-week course of investigation. However, complete reversal of all effects was not attained. TFE and its commercial formulations should be viewed as potentially severe human ocular irritants.

  3. Kabuki Syndrome: a case report with severe ocular abnormalities

    Directory of Open Access Journals (Sweden)

    Flavio Mac Cord Medina

    2013-10-01

    Full Text Available Kabuki syndrome is a rare congenital anomaly, characterized by five fundamental features, the "Pentad of Niikawa": dysmorphic facies, skeletal anomalies, dermatoglyphic abnormalities, mild to moderate mental retardation and postnatal growth deficiency. Patients present characteristic external ocular features, nonetheless they may also present significant ocular abnormalities. We report a case of a brazilian child diagnosed with Kabuki syndrome, addressing the clinical features observed, with emphasis on the ocular manifestations. This case highlights the existence of this syndrome and all of its complexity. The identification of preventable causes of loss of vision underlines the value of detailed ophthalmologic examination of Kabuki syndrome patients.

  4. Annual Burden of Ocular Toxoplasmosis in the United States

    OpenAIRE

    Jeffrey L. Jones; Holland, Gary N.

    2010-01-01

    Toxoplasmosis is the most common retinal infection in the United States, and it can severely impact vision. We used data from population-based studies, outbreaks, and the U.S. census to estimate the burden of Toxoplasma gondii infection and ocular toxoplasmosis. We estimate that 1,075,242 persons are infected with T. gondii, 21,505 persons have ocular lesions (both asymptomatic and symptomatic), and 4,839 (range = 2,150–7,527) persons develop symptomatic ocular toxoplasmosis each year in the ...

  5. Motor/generator

    Science.gov (United States)

    Hickam, Christopher Dale [Glasford, IL

    2008-05-13

    A motor/generator is provided for connecting between a transmission input shaft and an output shaft of a prime mover. The motor/generator may include a motor/generator housing, a stator mounted to the motor/generator housing, a rotor mounted at least partially within the motor/generator housing and rotatable about a rotor rotation axis, and a transmission-shaft coupler drivingly coupled to the rotor. The transmission-shaft coupler may include a clamp, which may include a base attached to the rotor and a plurality of adjustable jaws.

  6. Review of external ocular compression: clinical applications of the ocular pressure estimator

    Directory of Open Access Journals (Sweden)

    Korenfeld MS

    2016-02-01

    Full Text Available Michael S Korenfeld,1,2 David K Dueker3 1Comprehensive Eye Care, Ltd. Washington, MO, USA; 2Washington University Department of Ophthalmology and Visual Sciences, St Louis, MO, USA; 3Ophthalmology, Hamad Medical Corporation, Doha, Qatar Purpose: The authors have previously validated an Ocular Pressure Estimator (OPE that can estimate the intraocular pressure (IOP during external ocular compression (EOC. The authors now apply the OPE in clinical states where EOC is clinically important. The original work is described for two periods of risk: during sleep and during the digital ocular massage (DOM maneuver used by surgeons after trabeculectomy to keep the operation functional. Other periods of risk for external ocular compression are then reviewed.Methods: The first protocol estimated the IOP in the dependent eye during simulated sleep. Subjects had their IOPs initially measured in an upright-seated position, immediately upon assuming a right eye dependent side sleeping position (with nothing contacting the eye, and then 5 minutes later while still in this position. While maintaining this position, the fluid filled bladder of the OPE was then placed between the subject’s closed eye and a pillow during simulated sleep. The IOP was continuously estimated in this position for 5 minutes. The subjects then had the IOP measured in both eyes in an upright-seated position. The second protocol determined if a larger vertical cup-to-disc ratio was more common on the side that patients reported they preferred to sleep on. The hypothesis was that chronic asymmetric, compression induced, elevations of IOP during sleep would be associated with otherwise unexplained asymmetry of the vertical cup-to-disc ratio. The third protocol assessed the IOP during DOM. The OPE was used to characterize the IOP produced during the DOM maneuver of five glaucoma surgeons. After this, 90 mmHg was chosen as a target pressure for DOM. The surgeons were then verbally coached

  7. Piezoelectric Motors, an Overview

    Directory of Open Access Journals (Sweden)

    Karl Spanner

    2016-02-01

    Full Text Available Piezoelectric motors are used in many industrial and commercial applications. Various piezoelectric motors are available in the market. All of the piezoelectric motors use the inverse piezoelectric effect, where microscopically small oscillatory motions are converted into continuous or stepping rotary or linear motions. Methods of obtaining long moving distance have various drive and functional principles that make these motors categorized into three groups: resonance-drive (piezoelectric ultrasonic motors, inertia-drive, and piezo-walk-drive. In this review, a comprehensive summary of piezoelectric motors, with their classification from initial idea to recent progress, is presented. This review also includes some of the industrial and commercial applications of piezoelectric motors that are presently available in the market as actuators.

  8. Motor degradation prediction methods

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, J.R.; Kelly, J.F.; Delzingaro, M.J.

    1996-12-01

    Motor Operated Valve (MOV) squirrel cage AC motor rotors are susceptible to degradation under certain conditions. Premature failure can result due to high humidity/temperature environments, high running load conditions, extended periods at locked rotor conditions (i.e. > 15 seconds) or exceeding the motor`s duty cycle by frequent starts or multiple valve stroking. Exposure to high heat and moisture due to packing leaks, pressure seal ring leakage or other causes can significantly accelerate the degradation. ComEd and Liberty Technologies have worked together to provide and validate a non-intrusive method using motor power diagnostics to evaluate MOV rotor condition and predict failure. These techniques have provided a quick, low radiation dose method to evaluate inaccessible motors, identify degradation and allow scheduled replacement of motors prior to catastrophic failures.

  9. Neuroplasticity & Motor Learning

    DEFF Research Database (Denmark)

    Jensen, Jesper Lundbye

    Practice of a new motor task is usually associated with an improvement in performance. Indeed, if we stop practicing and return the next day to the same task, we find that our performance has been maintained and may even be better than it was at the start of the first day. This improvement...... is a measure of our ability to form and store a motor memory of the task. However, the initial memory of the task is labile and may be subject to interference. During and following motor learning plastic changes occur within the central nervous system. On one hand these changes are driven by motor practice......, on the other hand the changes underlie the formation of motor memory and the retention of improved motor performance. During motor learning changes may occur at many different levels within the central nervous system dependent on the type of task and training. Here, we demonstrate different studies from our...

  10. A biophysical approach to the spatial function of eye movements, extraocular proprioception and the vestibulo-ocular reflex.

    Science.gov (United States)

    Daunicht, W J

    1988-01-01

    The eyeball and the extraocular muscles are used as a paradigm to design a linear spatial model of a single joint with a redundant set of muscles. On the basis of this model relations are derived between orientation, torque, motor commands, and proprioceptive signals. These relations show that the tenet underlying the tensorial interpretation of neural signals in sensorimotor systems does not have general validity. A mechanism is proposed to show how proprioception may play a role in optimizing the coordination of muscles during spatial tasks. Further, a new concept is suggested that allows one to predict the neural connectivities mediating the redundant spatial vestibulo-ocular reflex. This concept has the advantage of minimizing both sensorial error and motor effort.

  11. The effects of lateral head tilt on ocular astigmatic axis

    Directory of Open Access Journals (Sweden)

    Hamid Fesharaki

    2014-01-01

    Conclusion: Any minimal angle of head tilt may cause erroneous measurement of astigmatic axis and should be avoided during refraction. One cannot rely on the compensatory function of ocular counter-torsion during the refraction.

  12. Progressive hemifacial atrophy with ciliary body atrophy and ocular hypotony

    Directory of Open Access Journals (Sweden)

    T Ashwini Kini

    2015-01-01

    Full Text Available Progressive hemifacial atrophy (PHA is a disease of unknown etiology affecting one-half of the face. Ocular involvement is uncommon. Atrophy of iris is rare, with only a few cases of partial atrophy being reported in the literature. We report a case of total atrophy of iris and ciliary body with associated ocular hypotony in a 16-year-old girl with PHA. We believe this is the first reported case of complete atrophy of iris and ciliary body in PHA. Ocular hypotony in PHA was thought to be due to intra-ocular inflammation. However in our case it appears to be secondary to severe atrophy of the ciliary body.

  13. Does topical voriconazole trigger dysplastic changes on the ocular surface?

    Science.gov (United States)

    Palamar, Melis; Egrilmez, Sait; Yilmaz, Suzan Guven; Polat, Suleyha Hilmioglu; Gunduz, Omur Ucakhan

    2015-02-01

    Systemic voriconazole treatment was reported to cause photosensitivity and related cutaneous malignancies. The aim of this report is to demonstrate a graft-related Candida endophthalmitis case that developed ocular surface dysplastic changes after receiving topical 1% voriconazole treatment. Full ocular examination, photography, and in vivo confocal microscopy examination (Rostock Cornea Module/HRT II, Heidelberg, Germany) were performed. A 73-year-old male with graft-related Candida endophthalmitis that was on topical 1% voriconazole for 4 months developed a whitish gelatinous lesion on the cornea originating from the nasal limbus. In vivo confocal microscopy examination revealed mild dysplastic changes in the cornea epithelium. Topical voriconazole might trigger neoplastic changes on the ocular surface as reported with systemic use in other sun-exposed parts of the body. Further studies are needed to relate topical use of voriconazole with ocular surface dysplasia.

  14. Intra-bleb hematoma and hyphema following digital ocular compression

    Directory of Open Access Journals (Sweden)

    Sagar Bhargava

    2014-01-01

    Full Text Available We report successful outcome of a huge post- trabeculectomy intra-bleb hematoma and hyphema that occurred following digital ocular compression. The patient was a 64-year-old lady suffering from bilateral primary angle closure glaucoma and cataract. She was on anti-platelet therapy. She underwent single-site phacoemulsification, intra-ocular lens implantation and trabeculectomy with mitomycin C in the right eye. The trabeculectomy was under-filtering. She was asked to perform digital ocular compression thrice daily. On 15 th post-operative day, she presented with a huge intra-bleb hematoma and hyphema. The hematoma did not respond to conservative measures and was drained to prevent bleb failure. We recommend caution in the consideration of digital ocular compression in patients on prophylactic anti-coagulation.

  15. Paintball related ocular injuries: First case report in Saudi patients

    Directory of Open Access Journals (Sweden)

    Mohammad Al-Amry

    2017-01-01

    Full Text Available Paintball is a popular recreational sport. This case series describes three Saudi patients exposed to paintball ocular injuries with sever ocular trauma. Two patients developed hyphema and traumatic cataract and one patient had vitreous hemorrhage, choroidal detachment, commotio retinae and retinal tear. All patients require surgical intervention. Final best corrected visual acuity was 20/200, 20/30 and 20/50 respectively. Paintball related ocular injuries can result in severe visual loss and in most of the time requires surgical intervention. Most injuries occur in under-supervised settings and are easily preventable. Our main aim was to increase awareness among local ophthalmologists and eye professionals about this new game. Improved safety measures and appropriate public education could prevent such serious ocular injuries.

  16. Paintball related ocular injuries: First case report in Saudi patients.

    Science.gov (United States)

    Al-Amry, Mohammad; Al-Ghadeer, Huda

    2017-01-01

    Paintball is a popular recreational sport. This case series describes three Saudi patients exposed to paintball ocular injuries with sever ocular trauma. Two patients developed hyphema and traumatic cataract and one patient had vitreous hemorrhage, choroidal detachment, commotio retinae and retinal tear. All patients require surgical intervention. Final best corrected visual acuity was 20/200, 20/30 and 20/50 respectively. Paintball related ocular injuries can result in severe visual loss and in most of the time requires surgical intervention. Most injuries occur in under-supervised settings and are easily preventable. Our main aim was to increase awareness among local ophthalmologists and eye professionals about this new game. Improved safety measures and appropriate public education could prevent such serious ocular injuries.

  17. Ocular Dynamics of Bolus Ingestion of Eleis guineensis Sap (Palm ...

    African Journals Online (AJOL)

    Elaeis guineensis), and is widely consumed among the various ethnic nationalities in Nigeria. The effect of bolus ingestion of 600ml, palm wine was undertaken so as to determine its ocular dynamics in healthy volunteers. Results showed that ...

  18. Ocular and oral grading of mucous membrane pemphigoid.

    Science.gov (United States)

    Reeves, Graham M B; Lloyd, Marianne; Rajlawat, Bijaya P; Barker, Gillian L; Field, E Anne; Kaye, Stephen B

    2012-04-01

    A variety of methods have been described for grading ocular mucous membrane pemphigoid (MMP), each with their own limitations. In contrast, there are no reported grading systems for involvement of the oral mucosa. We wished to evaluate two ocular (one established and one proposed) and an oral mucosal grading system for MMP. Patients with MMP were assessed by three ophthalmologists and two oral medicine physicians. Ocular disease was graded using the system described by Rowsey and a proposed system based on measurement of vertical depth and horizontal width measured from the bulbar conjunctival aspect. Oral assessment used a 'mucosal disease severity score' originally described for lichen planus, in which 17 areas of the mouth are scored for involvement, together with a pain score. Levels of agreement were evaluated using Fleiss' Kappa Statistic (k). Forty-four patients with MMP encompassing mild to severe disease were included. Good levels of agreement were observed between observers for both vertical (k:0.86) (upper 95% CI: 1.03 mm) and horizontal (k:0.80) (upper 95% CI: 3.01 mm) involvement for the proposed ocular system and the Rowsey system (k: 0.83) (upper 95% confidence interval: 3.19 mm). There was a high coefficient of determination (R(2)) between the ocular grading systems (0.81, p < 0.01). Oral grading showed excellent levels of agreement (k: 0.71) between observers. There was no significant association between the severity of oral and ocular disease using described grading systems. The proposed grading systems for both oral and ocular involvement in MMP are easy to use, and show good agreement between observers. The proposed ocular system correlates well with a currently used system, and overcomes some of the difficulties encountered with existing systems. For the individual patient, changes greater than 1.5 mm (vertical) and 3 mm (horizontal) are significant. This may increase our ability to detect change or disease progression. Although the

  19. Ocular Biometry and Cornea Biomechanics in Hypermetropic Anisometropia

    OpenAIRE

    Ebru Demet Aygıt; Zeynep Alkın; Birsen Gökyiğit; Hülya Güngel; Ahmet Demirok

    2014-01-01

    Objectives: To evaluate ocular biometric parameters including anterior chamber depth (ACD), corneal curvature (CC), central corneal thickness (CCT), horizontal corneal diameter, and corneal biomechanical properties using ocular response analyzer (ORA) in eyes with hypermetropic anisometropia and to compare the results with those obtained for the healthy eyes of the patients. Materials and Methods: Sixty-four eyes of 32 patients followed with the diagnosis of hypermetropic anisometrop...

  20. Subconjunctival hemorrhage and vision loss after regional ocular anesthesia.

    Science.gov (United States)

    Behera, Umesh Chandra; Panda, Lapam; Gupta, Sumi; Modi, Rohit Ramesh

    2017-04-22

    To report two cases of retinal vascular occlusion and associated subconjunctival hemorrhage in needle optic nerve injury during local bulbar anesthesia. Surgical records of these two subjects who presented with acute vision loss after cataract extraction were studied, and systemic workup and ocular imaging were carried out to establish the cause. Computerized tomography showed evidence of optic nerve injury. Subconjunctival hemorrhage could be an associated clinical finding in hypodermic needle injury-related retinal vascular occlusion during ocular anesthesia.